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Spectrum Analyser Measurement Techniques

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					       Rohde & Schwarz 75 Year Anniversary

Spectrum Analyser Measurement Techniques




             Jerry Carpenter
             Business Development
             Rohde & Schwarz

           75 Year Anniversary, Israel, November 2008
Agenda

Frequency Counter
Phase Noise Marker
Noise Marker
Noise in Channel
N dB down
Peak List
Marker Demod
Adjacent Channel Power
Spurious Emissions Measurement
Latest Developments in Spectrum Analysers: The FSV




                  75 Year Anniversary, Israel, November 2008
 Agenda

Frequency Counter
Phase Noise Marker
Noise Marker
Noise in Channel
N dB down
Peak List
Marker Demod
Adjacent Channel Power
Spurious Emissions Measurement
Latest Developments in Spectrum Analysis: The FSV




                   75 Year Anniversary, Israel, November 2008
Frequency Counter

Frequency can be measured with normal Marker Accuracy according to
current sweep settings: SPAN, RBW, Sweeptime….
Espescially for large SPAN values, absolute frequency error can be large




                  75 Year Anniversary, Israel, November 2008
Frequency Counter
Example:       fSG = 1.000 000 000 GHz

Measurement 1: SPAN = 2 GHz,
               RBW     = 3 MHz
Marker Result: 1.000 004 500 GHz




Measurement 2: SPAN = 100 kHz,
               RBW     = 3 kHz
Marker Result: 1.000 000 100 GHz




                  75 Year Anniversary, Israel, November 2008
Frequency Counter

Reason for difference is not just different RBW, but also frequency grid:
Example: SPAN = 2 GHz, 501 points        4 kHz grid spacing


                                           4 kHz
Level




                                                   ...
                                                 501                 Freq
        fstart                                  points           fstop


                    75 Year Anniversary, Israel, November 2008
 Frequency Counter

If the measurement signal is not exactly on grid, there will be a frequency
    error when measuring with Markers



                                            4 kHz
Level




                                                    ...
                                                  501                 Freq
         fstart                                  points           fstop


                     75 Year Anniversary, Israel, November 2008
 Frequency Counter

If the measurement signal is not exactly on grid, there will be a frequency
    error when measuring with Markers
                                                                     Frequency Error !


                                               4 kHz
Level




                                                       ...
                                                     501                                Freq
            fstart                                  points                          fstop
        This Frequency Error is independant of the RBW. It is directly related to
        the limited number of measurement points


                        75 Year Anniversary, Israel, November 2008
Frequency Counter
                          Measurement Method:
Solution:                 Analyzer stops sweep at Marker position
Frequency                 Analyzer does special frequency measurement
   Counter                  depending on RBW setting:

                                  1. RBW >200 kHz (analog Filter)
                                            Analyzer measures Zero-Crossings of IF

                                  2. RBW <200 kHz (digital Filter)
                                          Frequency measurement in IQ Baseband
                                       with special approximation algorithm

                          Important: No setup change! Counter can be
                             activated during any sweep setting!



             75 Year Anniversary, Israel, November 2008
Frequency Counter

The counter resolution can be selected:

Measurement Time:
RBW >200 kHz:
Time ~ 1/counter resolution in Hz

2. RBW <200 kHz:
   Time ~ 30 ms, independant of resolution




                  75 Year Anniversary, Israel, November 2008
Frequency Counter

Example Result:
Meas. With counter:
F = 999.999 999 976 Hz
  = 1 GHz – 24 Hz

previous results were:
F = 1 GHz + 4 500 Hz                      Counter
                                     measurement has
and                                    best reliability
                                    regarding frequency
F = 1 GHz + 100 Hz
                                         accuracy
depending on SPAN



                   75 Year Anniversary, Israel, November 2008
 Agenda

Frequency Counter
Phase Noise Marker
Noise Marker
Noise in Channel
N dB down
Peak List
Marker Demod
Adjacent Channel Power
Spurious Emissions Measurement
Latest Developments in spectrum Analysis: The FSV




                              ver y, sr ,
                    75 YearAnni sar I ael N ovem ber2008
Phase Noise Measurement Solutions

Your want to measure Phase Noise?                         Cost
You can
....      purchase an signal source analyzer              High

....      purchase a spectrum analyzer with              Medium
          options

....      purchase a spectrum analyzer and use            Low
          standard measurement function




            75 Year Anniversary, Israel, November 2008
Phase Noise Marker

 The FSx have a marker function for phase noise measurements.
 Indicates phase noise of an RF oscillator at any carrier in dBc in a
 bandwidth of 1 Hz.

 Result is calculated from normal sweep result:


      Phase Noise = LD + 10 x log (RBW / 1 Hz)
         LD = Displayed noise level with measurement bandwidth RBW
         RBW = Resolution bandwidth filter




                  75 Year Anniversary, Israel, November 2008
  Phase Noise Marker

                                                                Phase Noise
Offset can be
  changed                                                      in 10 kHz offset

                                                                  Carrier
  Amplitude                                                     Frequency
  reference
= Carrier Level
                                                                Reference for
                                                               offset = Carrier
                                                                  frequency




                  75 Year Anniversary, Israel, November 2008
Phase Noise Marker

Differences of Phase Noise Marker to other solutions:

FSx + FS-K40 or FS-K4:
                                                               FSUP:
  Can show complete plot of Phase
                                                                 Same as FSx Solution
  Noise vs. Offset, not just one offset
  value. Different Meas. Settings in                             Offers PLL method
  various offset ranges possible.
                                                                 Offers Cross-Correlation
  Can do advanced features like
                                                                 Full Spectrum Analyser
  tracking
                                                                 Funtions
  Accounts for k factor and RBW
  shape factor

                  75 Year Anniversary, Israel, November 2008
 Agenda

Frequency Counter
Phase Noise Marker
Noise Marker
Noise in Channel
N dB down
Peak List
Marker Demod
Adjacent Channel Power
Spurious Emissions Measurement
Latest Developments in Spectrum Analysis: The FSV




                     75 Year Anniversary, Israel, November 2008
Noise Marker (Noise Power Density)

Noise measurements play an important role in spectrum analysis.
Noise e.g. affects the sensitivity of radiocommunication systems and
their components.

Noise power is specified either as the total power in the transmission
channel or as the power referred to a bandwidth of 1 Hz.

The noise at the output of an amplifier is determined by its noise
figure and gain.

FSx can measure Noise Power Density (power referred to 1 Hz)
without additional options.




                   75 Year Anniversary, Israel, November 2008
Noise Marker

Calculation method of noise power density

l Automatic switch to Sample detector, VBW = RBW/10
l Take an average over 17 adjacent pixels
l Stabilize measurement by video filtering
l Average and filtering done in log mode                         Correction of 2.51 dB
 (difference between logarithmic noise average and noise power)
l Normalize to 1 Hz by application of correction factor
            - Factor = -10 x log (RBW / 1Hz)




                    75 Year Anniversary, Israel, November 2008
Noise Marker
l Noise is random   long measurement time has to be selected
l Can be achieved by averaging the trace or by selecting a small video
  bandwidth (VBW << RBW)




                    75 Year Anniversary, Israel, November 2008
Noise Marker

   Which detector to use?

   l Default Detector is SAMPLE detector
   l Also RMS detector will give correct results
   l Averaging depends on Sweep time (SWT/501) and can be increased
     to stabilize results
   l In case of SAMPLE detector:    Average of linear video voltage
   l In case of RMS detector:       Average of squared video voltage
   l FSx automatically corrects result depending on detector
      (SAMPLE    +1.05 dB; RMS                +0.0 dB)
   l MAX PEAK, MIN PEAK, AUTO PEAK and QUASI PEAK detectors are
    not suitable for noise measurement




                75 Year Anniversary, Israel, November 2008
Noise Marker

Example:
Determine Noise Figure of FSP
                                                                 50 Ω
Measured Noise Power Density:
PNoise = -154 dBm/Hz
Gain = 0 dB (50 Ohm directly at input)
  NF = -154 dBm/Hz + 174 dBm = 20dB


  NF of FSP at 1 GHz = 20 dB




                    75 Year Anniversary, Israel, November 2008
Noise Marker
Determining Noise Figure of DUT, e.g. amplifier:



                            DUT
        50 Ω


50 Ohm resistor has a noise power of P = k x T

P = -174 dBm/Hz (k = 1.38x10-23 Ws/K, T = 290 K, B = 1 Hz)

NF of DUT:       NF = Pnoise + 174 dBm – G

                 Pnoise      = Noise Power Density measurement
                 G           = Gain of DUT



                    75 Year Anniversary, Israel, November 2008
Noise Marker

Example 2: Noise Figure of DUT

                   DUT                                         Spectrum
                                                               Analyzer
  50 Ω             NF1                                           NF2
 SA measures intrinsic internal noise power as well as noise power of DUT
 For determination of NF of DUT, the SA internal noise power has to be
 subtracted

 NF of DUT:       NF = (PNoise – PNoise,int) + 174 dBm – G

                  PNoise     = Noise Power Density measurement
                  PNoise,int = Intrinsic Analyzer noise, without DUT
                  G          = Gain of DUT


                  75 Year Anniversary, Israel, November 2008
Noise Marker
Correction Factor for Noise Figure




Total Power                    = Noise Power Density measurement with DUT
Intrinsic Noise Power          = Intrinsic Analyzer noise, without DUT

                    75 Year Anniversary, Israel, November 2008
 Agenda

Frequency Counter
Phase Noise Marker
Noise Marker
Noise in Channel
N dB down
Peak List
Marker Demod
Adjacent Channel Power
Spurious Emissions Measurement
Latest developments in Spectrum Analysis: The FSV




                     75 Year Anniversary, Israel, November 2008
       Noise Power inside a Transmission Channel
Question:
What is the noise power inside a Transmission Channel,
e.g. 1.23 MHz bandwidth at 1 GHz RF frequency ?

Solution 1:        Noise Marker function, correction with bandwidth
                   correction factor = 10 x log (BW / 1Hz)
                                     = 10 x log (1.23 MHz / 1 Hz)
                                     = 60.9 dB

But: If noise inside channel is not flat, wrong result!!




Solution 2: Channel Power function




                       75 Year Anniversary, Israel, November 2008
Noise Power inside a Transmission Channel
Step 1: Set CF = 1 GHz and SPAN = 2 MHz

Step 2: Set RF ATT = 0 dB
        ( this yields maximum sensitivity)

Step 3: Switch on Channel Power Meas and Configure


Step 4: Set Channel Bandwidth = 1.23 MHz


Step 5: Press „Adjust Settings“
        (this selects the optimum RBW, VBW and
        detector for these settings)




              75 Year Anniversary, Israel, November 2008
Noise Power inside a Transmission Channel

Result:




 To normalize the Noise power to 1 Hz
 bandwidth (= noise power density),
 press CH PWR / Hz




                  75 Year Anniversary, Israel, November 2008
 Agenda

Frequency Counter
Phase Noise Marker
Noise Marker
Noise in Channel
N dB down
Peak List
Marker Demod
Adjacent Channel Power
Spurious Emissions Measurement
Latest Developments in Spectrum Analysis: The FSV




                     75 Year Anniversary, Israel, November 2008
N dB down Marker

Motivation:
User frequently needs to measure bandwidth, e.g. of filter, transmission channel
or characterize shape factors:

                                                                   Max
              Power



                                                                         n dB




                                                                                freq

                                  What is the n dB bandwidth?

                      75 Year Anniversary, Israel, November 2008
N dB down Marker
Solution 1:
Use several markers and delta markers and find the bandwith manually
Solution 2:
N dB down function
                                                               ndB value can be set individually




                  75 Year Anniversary, Israel, November 2008
N dB down Marker

Example:
Measure Shape factor of 10 kHz RBW filter
(Shape factor = 60 dB-bandwidth / 3 dB-bandwidth




   Result 10.2kHz                                              Result 47.4kHz




                  75 Year Anniversary, Israel, November 2008
N dB down Marker

Example:

                  BW 60dB                  47.4
 Shape Factor =                        =               = 4.65
                  BW 3dB                   10.2

Compare with specification (here: FSP):




                  75 Year Anniversary, Israel, November 2008
 Agenda

Frequency Counter
Phase Noise Marker
Noise Marker
Noise in Channel
N dB down
Peak List
Marker Demod
Adjacent Channel Power
Spurious Emissions Measurement
Latest Developments in Spectrum Analysis: The FSV




                     75 Year Anniversary, Israel, November 2008
Peak List

 Task: Determine frequencies and levels of dedicated peaks in the
 spectrum




How can you do it most easily?


                  75 Year Anniversary, Israel, November 2008
Peak List
Answer: Use Peak List

The Peak List automatically searches for peaks.

You can define the evaluation range (LEFT LIMIT and RIGHT LIMIT frequency)

You can limit the amplitude threshold (minimum required amplitude for a peak)

And you can define how much a peak must exceed the vicinity (Peak Excursion)




                     75 Year Anniversary, Israel, November 2008
Peak List

 Example: If peak excursion is set to 35 dB

 Result: Only peaks which exceed 35dB are recognized as peaks




                  75 Year Anniversary, Israel, November 2008
 Agenda

Frequency Counter
Phase Noise Marker
Noise Marker
Noise in Channel
N dB down
Peak List
Marker Demod
Adjacent Channel Power
Spurious Emissions Measurement
Latest Developments in Spectrum Analysis: The FSV




                     75 Year Anniversary, Israel, November 2008
Marker Demod

Question:

Which of the two instruments is an AM/FM radio receiver?




                 75 Year Anniversary, Israel, November 2008
Marker Demod

The FSx offer the possibility to demodulate the signal at the
marker position

Possible demodulations are AM and FM


Two different measurements can be done:

Frequency domain:
Sweep stops at marker and demodulates marker frequency

Time Domain:
Continuous demodulation of the setup center frequency




                  75 Year Anniversary, Israel, November 2008
Marker Demod

       Activation key for demodulation



       Select between Amplitude and Frequency Moduation



       Set an amplitude threshold level

       Define the demodulation time period

       Demodulate not only at marker position, but
       continuously. For large sweep times, the complete
       frequency span can be monitored

           75 Year Anniversary, Israel, November 2008
Marker Demod
Example: Listen to FM Radio
Step 1: Connect Antenna to Spectrum Analyzer RF input
Step 2: Examine FM Radio Frequency Band:



                                                                 Different FM
                                                                radio stations




                   75 Year Anniversary, Israel, November 2008
Marker Demod

 Step 3: Place Marker on desired FM radio station
 Step 4: Activate Marker Demod, set to FM demodulation
 Step 5: Increase the marker demod time to e.g. 1s (MKR Stop Time)
 Step 6:   If necessary, increase the audio volume on the FSP front panel




 You can also connect headphones to the
 FSP front panel (3.5mm connector)




                    75 Year Anniversary, Israel, November 2008
Marker Demod

 In order to monitor the complete FM band, increase the sweeptime to a high
 value, e.g. 20 s and press „CONT DEMOD“ for continuous demodulation


 Now you can listen to the
 demodulated signal during the
 sweep
 At the sweep points where an
 FM station is transmitting, you
 get music. The other points are
 noise.                                                    Sweeptime 20s




                    75 Year Anniversary, Israel, November 2008
 Agenda

Frequency Counter
Phase Noise Marker
Noise Marker
Noise in Channel
N dB down
Peak List
Marker Demod
Adjacent Channel Power
Spurious Emissions Measurement
Latest Developments in Spectrum Analysis: The FSV




                     75 Year Anniversary, Israel, November 2008
Adjacent Channel Power Measurement

 Why Adjacent Channel Power Measurement?
 Example: 3GPP Frequency allocation in Austria/Europe




             Interference!

                             Provider 1             Provider 2




  Neighboring channels must not be disturbed by noise and spurious from
  other channels!

                   75 Year Anniversary, Israel, November 2008
Adjacent Channel Power Measurement
Example: Korean Wimax-System (Wibro) in 2.3 GHz Band




       A1 A2 A3                  B1 B2 B3                         C1 C2 C3

       Guard band                                     Channel            Guard band
        = 4.5 MHz                                    bandwidth            = 0.5 MHz
(between different providers                                           (same provider)
                                                    = 8.75 MHz


                     75 Year Anniversary, Israel, November 2008
Adjacent Channel Power Measurement

  Requirement to measure the power inside a certain frequency band


  Power Meter excellent for power measurment, but not frequency-selective
  Spectrum Analyzer is frequency selective, but is it showing the correct power?
           Spectrum Analyzer detectors are optimized for sinewave, i.e. they
                 show correct power only for sinewave signals
           Modulated signals are not sinewave Power Measurement Error
                with SA and normal detectors (PEAK, Sample, AVG, QP)
           Correction factor is possible, but only if the amplitude distribution of
                 the modulated signal is known (e.g. Gaussian Shape)
  For this reason, spectrum analyzers have true power detector: RMS detector
                                                     Type of Noise Signals

                  75 Year Anniversary, Israel, November 2008
Adjacent Channel Power Measurement

 RMS Detector:
   RMS Detector shows correct power inside RBW
   RMS Detector result is independant of amplitude distribution
   Measurement uncertainty                      Absolute           Relative
                                                <1.5dB (FSL)       <0.5dB (FSL)
                                                <0.5dB (FSP)       <0.2dB (FSP)
                                                <0.3dB (FSU,FSQ)   <0.1dB (FSU, FSQ)




                   75 Year Anniversary, Israel, November 2008
 Adjacent Channel Power Measurement

   Measurment Solution in FSx:                    Adjacent channel power measurement




 RMS
Detector




                      Adjacent                                        Adjacent
                      Alternate
                      Tx Channel
                      Channels                                         Alternate
                                                                  Tx Channel Power
                      Channels                                     Channel Power
                                                                    Channel Power
                     75 Year Anniversary, Israel, November 2008
Adjacent Channel Power Measurement

 ACP: How to setup
 1.   Automatic Setup
 If the measured signal is according to a known
       standard, you can choose an automatic
       setup from a dropdown list:




                     75 Year Anniversary, Israel, November 2008
Adjacent Channel Power Measurement

 Automatic Setup


 The FSx then automatically sets up parameters like bandwith and spacing.
 Example: Setup after choosing WCDMA FWD standard setting:

         Channel Bandwidth:                                     Channel Spacing:




                   75 Year Anniversary, Israel, November 2008
Adjacent Channel Power Measurement

 2.   Manual Setup
 You can setup bandwidth, spacing, no of channels individually.
 Example:                                             4           3   2   1   1   2   3   4

                     4




                 2 MHz


                10 MHz


                     75 Year Anniversary, Israel, November 2008
Adjacent Channel Power Measurement

 There are two possible ways to measure:

 Integration BandWidth Method (IBW, frequency domain method)
     Analyzer measures with an RBW <<Signal Bandwidth
     Analyzer integrates the level values of the trace versus the Signal Bandwidth


 Channel Filter Method (Fast ACP Method, Time Domain Method)
     Analyzer measures in Time Domain
     IF Filter = Signal Bandwidth
     IF Filter must have high selectivity (steep edges)         Channel Filter



                   75 Year Anniversary, Israel, November 2008
Adjacent Channel Power Measurement

 Advantages and disadvantages of the two methods:

 Integration Bandwidth Method (IBW, frequency domain method)
     +   Easy to setup
     +   Standard Gaussian RBW can be used
     -   For high repeatability (especially in small channels), long measurment
         time is required


 Channel Filter Method (Fast ACP Method, Time Domain Method)
     +   Much faster compared to IBW method
     -   Special Channel Filter with steep edges required


                  75 Year Anniversary, Israel, November 2008
Adjacent Channel Power Measurement

 Example: Setup of Fast ACP for a CDMA2000 Signal
 1.   General Setup of Analyzer
      (CENTER, SPAN, REF LVL)
 2.   Switch on ACP and select CDMA2000 from the standards dropdown list

          Automatic setup for
      -    2 adjacent channels
      -    Tx bandwidth = 1.2288 MHz
      -    Adjacent+Alternate bandwidth = 30 kHz
      -    Optimum RBW, VBW
      -    RMS Detector

                     75 Year Anniversary, Israel, November 2008
Adjacent Channel Power Measurement

 3.   Press ADJUST REF LEVEL
        FSx selects optimum ATT and REF LVL for the measured signal power
 4.   The Result is measured with IBW method:




                   75 Year Anniversary, Israel, November 2008
Adjacent Channel Power Measurement

Note regarding measurement time:
In the above example:
T = 100 ms, SPAN = 5 MHz, RBW = 30 kHz
                                      100 ms
   Meas. Time per adjacent channel =                                    x 30 kHz = 600 µs / RBW
                                      5 MHz
                                                                                    Meas. Time for one adjacent channel
                                                                                    (30 kHz) is by 1288/30 = 43 x longer

Note regarding uncorrelated samples:
1 uncorrelated sample in 1/30 kHz = 33.3 µs

                                               600 µs
Uncorrelated samples / channel =                                 = 18 samples
                                             33.3 µs             No. of samples in one adjacent channel
                                                                   (30 kHz) is by 1288/30 = 43 x larger




                    75 Year Anniversary, Israel, November 2008
Adjacent Channel Power Measurement

 5. Switch to FAST ACP Method




                  75 Year Anniversary, Israel, November 2008
Adjacent Channel Power Measurement

 In Fast ACP mode, the setup measurment time is divided equally between the Tx
      channel and adjacent and alternate channels
 Example: Sweeptime = 100ms, 2 adjacent/alternate channels left and right
     Total 5 channels, each channel measurement time is 20 ms


 For each channel, the FSx is using the appropriate channel filter
 In the CDMA2000 example above:
               30 kHz channel filter for the adjacent/alternate channels
               1.3 MHz channel filter for the Tx channel




                    75 Year Anniversary, Israel, November 2008
Adjacent Channel Power Measurement

 Watch the measurement Sequence:




                                      Measurement
                                         Start!




                     Measurement Time = 20 ms
                      Lower Alternate Channel
                        Channel Filter = 30 kHz
                 75 Year Anniversary, Israel, November 2008
Adjacent Channel Power Measurement

 Watch the measurement Sequence:




                     Measurement Time = 20ms
                      Measurement Time = 20 ms
                       Lower Adjacent Channel
                                    Tx Channel
                         Channel Filter 1.2288 MHz
                      Channel Filter = = 30 kHz
                 75 Year Anniversary, Israel, November 2008
Adjacent Channel Power Measurement

 Watch the measurement Sequence:




                     Measurement Time = 20ms
                     Measurement Time = 20 ms
                                   Adjacent
                       Upper Alternate Channel
                         Channel Filter = 30 kHz
                 75 Year Anniversary, Israel, November 2008
Adjacent Channel Power Measurement

Note regarding measurement time:
In the above example: T = 100 ms



   Meas. Time per adjacent channel =                             20 ms


Note regarding uncorrelated samples uncorrelated samples:
1 uncorrelated sample in 1/30 kHz = 33.3 µs

                                               20 ms
Uncorrelated samples / channel =                                 = 600 samples
                                             33.3 µs              No. of samples for one adjacent
                                                                       channel measurement




                    75 Year Anniversary, Israel, November 2008
Adjacent Channel Power Measurement
Comparison IBW method / Fast ACP method:

                                                    IBW Method                      Fast ACP method


Total measurement time for ACP                             100 ms                            100 ms
(Tx + 4 ACP)

Uncorrelated samples / channel =                               18                            600
                                                                    33 x more samples with
                                                                       same meas. time
  Fast ACP gives better repeatability (more stable readout despite of low S/N) with
same measurement time
   .... or: same repeatability with much faster measurement (in this case 33 times
faster)
                              Fast ACP Details

                      75 Year Anniversary, Israel, November 2008
Adjacent Channel Power Measurement

 Important Adjustments:

Adjust Settings
    Press always after changing bandwidth, spacing etc.
    Adjusts RBW ≤ 1/40 of channel bandwidth
    Adjusts VBW ≥ 3 x RBW
    Selects automatically RMS Detector

Adjust Reference Level
     Adjusts REF LVL and ATT of the FSP to the measured channel power
    Finds optimum REF LVL setting (sweet spot)
    Avoids overload FSP
    Avoids limiting dynamic range by too small S/N
    In IBW method, since RBW <<Signal bandwidth, signal path may be
    overloaded although the trace is still significantly below the reference level.


                     75 Year Anniversary, Israel, November 2008
Agenda

Frequency Counter
Phase Noise Marker
Noise Marker
Noise in Channel
N dB down
Peak List
Marker Demod
Adjacent Channel Power
Spurious Emissions Measurement




                  75 Year Anniversary, Israel, November 2008
Spurious Measurements

 Spurious Signals are signals that are not part of the wanted transmission signal,
     but which are appearing in the spectrum
 Origin can be nonlinearities in the transmission path (intermodulation,
      harmonics), but also interference from other systems

                                            Wanted Signal
 Power




                                                    Spurious!




                                                                 Freq.


                    75 Year Anniversary, Israel, November 2008
Spurious Measurements

 Often Spurious levels are very low
     In order to measure you need high dynamic range (low RBW)
     Often specified over wide frequency range
     Low RBW measurement can take very long time
     Often regulation bodies define the measurement conditions at certain
     frequencies, e.g. Which RBW, which Ref LVL




                    75 Year Anniversary, Israel, November 2008
Spurious Measurements

 Example: Emission Mask definition as from 3G TSG RAN (UE)




                           -8MHz




                                                                               +7.5MHz
                                                                                         +8MHz
                                   -7.5MHz
                                                                                                 Measure with RBW=30kHz
                                                                                                 Measure with RBW=100kHz
                                                                                                 Measure with RBW=300kHz


                                                         +2.5 MHz
                                             -3.5 MHz
                                             -2.5 MHz



                                                        CF          +3.5 MHz




              Impossible to measure with one normal sweep!
                    (1 sweep = fixed RBW, VBW, ....)


                  75 Year Anniversary, Israel, November 2008
Spurious Measurements

        Solution: Spurious Measurements
          Segmentation of the sweep range
Power




                                                                           Range n-1
                                Range 2
                    Range 1




                                             Range 3




                                                                                       Range n
                                                               ...
                                                                                                 Freq
               fstart                                                                    fstop

                              75 Year Anniversary, Israel, November 2008
Spurious Measurements

        Each range can have different sweep settings
        (different values for RBW/VBW, sweeptime, detector, REF LVL, ATT, ...)
        Max. 20 ranges
Power




                         #1      #2           #3                              #n-1         #n


                    RBW1       RBW2         RBW3                            RBW_n-1      RBW_n




                                                               ...
                    VBW1       VBW2         VBW3                            VBW_n-1      VBW_n
                   Tsweep1    Tsweep2      Tsweep3                         Tsweep_n-1   Tsweep_n
                    DET1       DET2         DET3                            DET_n-1      DET_n
                    RLVL1      RLVL2        RLVL3                           RLVL_n-1     RLVL_n
                    ATT1       ATT2         ATT3                            ATT_n-1      ATT_n
                      ...        ...          ...                              ...         ...




                                                                                                   Freq
                fstart                                                                     fstop

                              75 Year Anniversary, Israel, November 2008
Spurious Measurements
Example for segment setup in FSx:




              Individual Limit Check is possible


                   75 Year Anniversary, Israel, November 2008
Spurious Measurements

 Result:




                                                               Trace measured with individual
                                                                   Settings for each range
Limit
Line
                                                                       Press to start
                                                                       measurement
              List showing frequency and
           absolute peak power in each range



                  75 Year Anniversary, Israel, November 2008
Spurious Measurements

 Result:




                         Absolute                       Power relative
                        Peak Power                       to limit line




           75 Year Anniversary, Israel, November 2008
Spurious Measurements

 Result:




                           Highlight in
                           case of fail



           75 Year Anniversary, Israel, November 2008
Time Domain Measurement (Fast ACP)
Comparison of 3GPP channel filter with
resolution filters of spectrum analyzers
                                          20


 Spectrum analyzer                                   Channel filter   3 MHz resolution filter
                                          10

 resolution filters
 (nearly) gauss shaped                    0




    4 or 5 pole filters                   -10




    shape factor 12 or 9.5                -20



                                          -30



 Selectivity not sufficient               -40


 for channel power                        -50

 measurements
                                          -60



                                          -70


                                          -80




                  75 Year Anniversary, Israel, November 2008
Time Domain Measurement (Fast ACP)
Digital implementation of channel filters
in spectrum analyzers
                                                                             Lowpass filter
                                                       Q mixer
                                                 IF                 I
              Anti aliasing
               bandpass          12 bit
                                                               LO
IF 20.4 MHz                      A                                                                           IF envelope voltage
                                                                                                   2     2
                                                         90°                filter coefficients   I +Q
                                       D                                     Lowpass filter
                                                        I mixer
                                                                    Q
                                32 MHz           IF


                                                             LO


                                                                            filter coefficients

                                                        NCO                Digital Resolution
                                                                              Bandwidths




                              75 Year Anniversary, Israel, November 2008
Time Domain Measurement (Fast ACP)
                                       Ref   20.8 dBm         * Att   40 dB       SWT   100 ms

Fast ACP test result                   10

                                       0                                                                    A

                                       -10
                                1 RM *
                                CLRWR -20

  Channel power                 2 PK *
                                       -30
                                       -40
                                VIEW
  measurement using                    -50
                                       -60

  the RMS detector                     -70                                                                  PRN


                                       Center 2.2 GHz                         10 ms/


  Peak power (due to                    Tx Channel
                                        Power                   8.78 dBm         Bandwidth       3.84 MHz


  switching) using                      Adjacent Channel
                                        Lower                 -49.60 dBc         Bandwidth       3.84 MHz

  peak detector                         Upper                 -49.78 dBc         Spacing            5 MHz

                                        Alternate Channel
                                        Lower                 -51.75 dBc         Bandwidth       3.84 MHz
                                        Upper                 -51.77 dBc         Spacing           10 MHz




                               Date:          3.MAR.2000   15:43:53




                75 Year Anniversary, Israel, November 2008
Comparison
Basic considerations

   Digital modulated signals are statistical signals
   (noise like signals)

   Averaging over de-correlated samples required to get
   stable and repeatable results
      time between de-correlated samples = 1 / RBW

   Uncertainty of < 0.5 dB requires averaging over
      >300 samples (95 % confidence level)
      >600 samples (99 % confidence level)




                  75 Year Anniversary, Israel, November 2008
  Comparison
  IBW method: standard deviation vs sweep time (3GPP)
                                  0,6
                                                                                          TX Channel
                                                                                          Lower adjacent channel
                                  0,5
                                                                                          Upper adjacent channel
        standard deviation / dB




                                                                                          Lower alternate channel
                                  0,4                                                     Upper alternate channel


                                  0,3


                                  0,2


                                  0,1


                                   0
                                        10                                      100                            1000

                                                                      meas time / ms *)
*) Overall measurement time for channel power measurement in TX channel,
   upper/lower adjacent channel and upper/lower alternate channel (3GPP signal)

                                             75 Year Anniversary, Israel, November 2008
Comparison
Time domain measurement:
standard deviation vs meas time (3GPP)
                                 0,9
                                                                                                   TX Channel
                                 0,8                                                               Lower adjacent channel
                                                                                                   Upper adjacent channel
                                 0,7
       standard deviation / dB




                                                                                                   Lower alternate channel
                                 0,6                                                               Upper alternate channel

                                 0,5

                                 0,4

                                 0,3

                                 0,2

                                 0,1

                                  0
                                       1                       10                            100                        1000
                                                                                        *)
                                                                      meas time / ms
*) Overall measurement time for channel power measurement in TX channel,
   upper/lower adjacent channel and upper/lower alternate channel (3GPP signal)

                                           75 Year Anniversary, Israel, November 2008
 Comparison
 Time domain measurement vs IBW method (3GPP)
                                 0,8
                                                                                        TX Channel (time domain)
                                 0,7                                                    Lower adjacent channel (time domain)
                                                                                        TX Channel (IBW)
       standard deviation / dB




                                 0,6                                                    Lower adjacent channel (IBW)

                                 0,5


                                 0,4


                                 0,3


                                 0,2


                                 0,1


                                  0
                                       1                      10                                100                            1000
                                                                                           *)
                                                                      meas time / ms
*) Overall measurement time for channel power measurement in TX channel,
   upper/lower adjacent channel and upper/lower alternate channel (3GPP signal)

                                           75 Year Anniversary, Israel, November 2008
Comparison
Test Time Comparison for 3 GPP
  Conditions
     Measurement of TX, upper/lower adjacent and alternate channels
     0.5 dB repeatability with 95 % confidence level (in TX channel)
     standard deviation (68 % confidence level) has
     to be multiplied with factor 1.96

  Theoretical values w/o overhead (eg for synthesizer switching)
     Time domain method                                         3 ms
     IBW method                                                43 ms


  Practical values (achieved with spectrum analyzer FSP)
     Time domain method                                        28 ms
     IBW method                                                84 ms   Back

                  75 Year Anniversary, Israel, November 2008
Comparison
Time domain measurement vs IBW method (IS-95)
                                     1,4
                                                                                             TX Channel (time domain)
                                     1,2                                                     Lower adjacent channel (time domain)
                                                                                             TX Channel (IBW)
           standard deviation / dB




                                      1                                                      Lower adjacent channel (IBW)


                                     0,8


                                     0,6


                                     0,4


                                     0,2


                                      0
                                           10                                         100                                           1000

                                                                              meas time / ms *)

*) Overall measurement time for channel power measurement in TX channel,
   upper/lower adjacent channel and upper/lower alternate channel (IS-95 signal)
                                                75 Year Anniversary, Israel, November 2008
Comparison
Time domain measurement vs IBW method (IS-136)

                                      2,5
                                                    TX Channel (time domain)
                                                    Lower adjacent channel (time domain)
                                       2            TX Channel (IBW)
            standard deviation / dB




                                                    Lower adjacent channel (IBW)

                                      1,5




                                       1




                                      0,5




                                       0
                                            10                                           100         1000
                                                                                                *)
                                                                               meas time / ms

*) Overall measurement time for channel power measurement in TX channel,
   upper/lower adjacent channel and upper/lower alternate channel (IS-136 signal)
                                                 75 Year Anniversary, Israel, November 2008
Comparison
Why is IBW method slower than time domain method?


   Narrow resolution bandwidth
   determines
     minimum sweep time
     time between de-correlated samples
     30 kHz (IBW) vs 3.84 MHz (time
     domain)

   Measurement of spectrum between
   channels



              75 Year Anniversary, Israel, November 2008
Comparison
Time Domain Method
Advantages
  Fast due to use of maximum possible bandwidth
  (equal to channel bandwidth)
  Only power of interest is measured
  Also peak power (eg due to switching transients) can
  be measured using peak detector instead of RMS detector


Disadvantages

  ADC loaded with full power of wideband signal
  Reduced dynamic range:
     FSU with IBW method: 77 dBc ACLR (3GPP)
     FSU with Time domain method (Fast ACP): appr 65 dBc ACLR (3GPP)


                 75 Year Anniversary, Israel, November 2008
Type of Noise Signals



   White Noise (thermal noise)
      power spectrum independent on frequency
   Colored Noise (e. g.. 1/f, 1/f2, filtered, ..)
      power spectrum frequency dependent
   Digital modulated Signals
      NADC, CDMA, WCDMA....
      (@ transmit channel)




               75 Year Anniversary, Israel, November 2008
Properties of Noise Signals

A noise signal consists of a large number of independent
randomly occurring processes

Amplitude and phase of noise are completely random or
pseudo-random in case of digital modulation

The amplitude distribution is a normal distribution
(Gaussian distribution)

Due to the distribution an average voltage or a power density
can be calculated and measured

Independent noise sources are additive in terms of power



                75 Year Anniversary, Israel, November 2008
Common Model: Gaussian Noise




         75 Year Anniversary, Israel, November 2008
Normal Distribution of White Noise
Description by statistical parameter
                noise amplitude




                                                                                           4σ = 95.45%

                                                                                                         6σ = 99.73%
                                                                                            σ

                                                                                                          σ
                                                                                            σ
                                                                                            σ

                                                                                                          σ
                                                                                                          σ
                                                                                2σ = 68%
                                                                                 σ
                                                                                 σ
                                                                                 σ
                                                              noise amplitude
                                                                distribution




                 75 Year Anniversary, Israel, November 2008
SA Components and their Impact on Noise
  Spectrum Analyzer. A Basic Block Diagram


                                                        Lin/Log                       Video
Internal                                                                   Envelope
           Input Mixer   IF Gain        IF Filter      Converter                      Filter
 Noise                                                                     Detector

                                                        lin                                     Trace
                                                                                               Detector    Display
    RF                                                        log
   Input

                          Ref Level       RBW           LIN/LOG                       VBW        PEAK     CLR WRITE
                                                     Display Range                              SAMPLE    MAX HOLD
            1st Local                                                                          AVERAGE    MIN HOLD
           4 to 8 GHz                                                                            RMS      AVERAGE




                              75 Year Anniversary, Israel, November 2008
Influence of the LO Phase Noise


       RF Frequency                         IF Frequency

          f                                 f                    f        = f        - f
              RF                                IF                   IF         LO         RF




                                 Local Oscillator
              frequency          f                                                                  frequency
                                   LO                            IF                  RF LO      Image




                                                     frequency



    Phase noise of local oscillator is directly converted to IF.


                   75 Year Anniversary, Israel, November 2008
IF Filter


l   Determines the Resolution Bandwidth (RBW)

l   Determines the selectivity

l   Determines the sensitivity

l   Determines minimum sweeptime




             75 Year Anniversary, Israel, November 2008
Analog IF Filter
                                       Synchroneous tuned filter stages

                 Stage 1                       Stage 2                    Stage n


           L     C                      L     C



           L 1
      Q=
           C R             R                        R




                     Bandwidth
                      Control




   Bandwidth for example tunable from 1 kHz to 5 MHz
   Selectivity determined by No. of stages
       4 stages (poles), shape factor 60 / 3 dB ~ 12
       5 stages (poles), shape factor 60 / 3 dB ~ 9
   Remark: GSM specs are based on 5-pole filter selectivity




                       75 Year Anniversary, Israel, November 2008
Digital IF Filter
                                                      IF
                                                    25 kHz

               IF Filter                Mixer                     18 bit

   21.4 MHz                                                   A
                                                                                 DSP
                                                                      D     18              24

              BW = 5 kHz
                                                                                      RBW

                                    21.375 MHz                    200 kHz        µP



Bandwidths from 1 Hz to 100/200 kHz
Gaussian type filter (FIR)
Selectivity 60:3 dB = 4.6




                     75 Year Anniversary, Israel, November 2008
Analog vs. digital Filter


                                                          1 kHz analog filter




                                   1 kHz digital filter




            75 Year Anniversary, Israel, November 2008
IF Filter Power Bandwidth

    Power            Noise bandwidth
                          BN


                                                         Equal. areas


                                                           Ideal recantangular filter




                                                           Resolution filter




                                                                    Frequency
             Equivalent for effective noise bandwidth


            75 Year Anniversary, Israel, November 2008
Noise Bandwidth of IF Filter
Examples: FSU/FSP

      No. of Poles                   RBWPower/            Correction-
                                      RBW3dB                factor

            4                             1.285           + 0.53 dB


            5                             1.114           + 0.45 dB


      digital filter                       1.04           + 0.02 dB



             75 Year Anniversary, Israel, November 2008
Signal Detection: the conventional way
                                                                pos. Peak


              Logarithmic            log video
               Amplifier
      IF
 (21.4 MHz)                                        Video                    A
               lin          Envelope               Filter
                            Detector             (1 Hz to
                     log                          n MHz)                            D    Display




                                                                                f
                                                                                    sample
                                                                neg. Peak
Traditional spectrum analyzers are good at measuring

l CW signals
l Signals with known and predictable amplitude distribution


                             75 Year Anniversary, Israel, November 2008
 Influence of the Logarithmic Amplifier
Compression of dynamic range by non-linear transformation of the IF
signal




          Output




                                         Input




                   75 Year Anniversary, Israel, November 2008
Compression of Noise Signals
Logarithmic compression turns the Normal Distribution of noise signal
into a Raleigh Distribution
   Positive peaks are compressed
   Negative peaks are enhanced
Error introduced for white noise = -1.45 dB
                                                       Amplitude




                   Logarithmic Noise                               Raleigh Distribution



                 75 Year Anniversary, Israel, November 2008
Envelope Detector
The envelope detector rectifies the IF signals

It removes the IF part of the signal

It delivers the envelope of the positive peaks of the IF
signal (video signal)

Bandwidth of the video signal is half the IF bandwidth

Phase information is lost due to rectifying




                75 Year Anniversary, Israel, November 2008
Envelope Detector
 amplitude
               Video output signal                amplitude

                                                                         Video output signal




                                                                             IF input signal
                      IF input signal

                                        time
                                                                                               time




   Linear IF Voltage                                          Logarithmic IF Voltage




                 75 Year Anniversary, Israel, November 2008
Video Filter
l Reduces bandwidth of video signal
l Averages noise signals
l Peak amplitudes are reduced
l Average Level
    VBW << RBW
l With channel power measurement VBW must not
  affect the video signal
    VBW >> RBW (3 to 10 x RBW)
l For noise power or phase noise measurement
  use small VBW
    VBW <<RBW (0.1 x RBW)


            75 Year Anniversary, Israel, November 2008
   Bandlimited Gaussian noise


 In baseband noise is a real signal
 In RF noise has
     phase and magnitude
     or
     In-phase and Quadrature
     components

SPA detects the magnitude of the
signal, i.e. length of the vector

Where is the highest count of
samples?


                    75 Year Anniversary, Israel, November 2008
          Count the samples in the coloured rings
180
                      166

160

                139
140


120


100
                                87

 80
           69


 60


 40                                        32



 20                                                  14

      2                                                         4

  0
      1    2    3     4         5          6         7          8




                            75 Year Anniversary, Israel, November 2008
Noise in linear display




           75 Year Anniversary, Israel, November 2008
Noise in log display




           75 Year Anniversary, Israel, November 2008
Peak and Sample Detector
 Max Peak Detector:
    captures the max video voltage for each pixel on
    screen
 Min. Peak Detector:
    captures the min. video voltage for each pixel
    on screen
 Auto Peak Detector:
    captures the max and min. video voltage for
    each pixel on screen
 Sample Detector
    takes an arbitrary sample for display




             75 Year Anniversary, Israel, November 2008
Adding RMS Detection

                                                                                  Pos. Peak



              Logarithmic
               Amplifier
                                                                                  neg. Peak
                lin

                      log                      Video
                                Envelope        Filter
                                                           A
                                Detector      (1 Hz to
                                              10 MHz)           D
      IF
 (21.4 MHz)
                                                                                  Sample
                                 100 dB                                                                          Display
                                dynamic
                                                                         RMS Detector             Lookup Table
                                                          f sample
                                                                                  N        V
                                                                              1             rms     lin
                                                          20 MHz         P=
                                                                          j           2
                                                                              N Vi
                                                                               i=1        16              log




                            75 Year Anniversary, Israel, November 2008
RMS and Average Detector


   RMS Detector:
     each pixel displays power of signal
     represented by the pixel
   AV Detector:
     each pixel displays average value of signal
     represented by the pixel




          75 Year Anniversary, Israel, November 2008
  Data Reduction for Display (RMS Detector)
RMS Detector:
    Each pixel displays power
    of signal represented by                     pixel n                     pixel n+1
    the pixel                                 (8 samples)                  (8 samples)
                                      s1 s2 s3 s4 s5 s6 s6 s8     s1 s2 s3 s4 s5 s6 s6 s8
Symbolic graph with only
  8 bins:
                                                                                            A/D samples
    number of data power-
                                                                                            (linear range)
    integrated to one pixel
    depends on sweep time
    20 MHz internal sample
    rate => 1 sample/50 ns
    500 pixels on-screen
                                                                                            displayed pixels
    1 s sweep time results in
    20,000 measured events                                                                   positive peak
    per pixel                                                                                sample
                                                                                                                      8
                                                                                                                 1
                                                                                             rms      p      =            s2
                                                                                                                           i
                                                                                                      rms        8
                                                                                                                     i =1
                                                                                             negative peak




                     75 Year Anniversary, Israel, November 2008
RMS and Average Detector

 RMS and AV calculation on linear video voltage
 Dynamic range is according to internal word length
         16 bit ~ 96 dB
 Trace smoothing by increase of sweeptime
         more samples per pixel available
         no trace averaging needed




            75 Year Anniversary, Israel, November 2008
Advantages of the rms detector


Indicates power independent of signal shape
        No correction factor needed
Does not violate the Nyquist criterion
        No signal is missing
No sample is lost for power measurement
        Test time is reduced
        Averaging is performed by increasing the sweeptime

        Back




               75 Year Anniversary, Israel, November 2008
Rohde & Schwarz Range of Spectrum Analysers



      R&S FSH18




    R&S FSL18




                       R&S FSU67




                  75 Year Anniversary, Israel, November 2008
Signal Analyzer FSV
The next generation
industry standard
in the mid range
 R&S FSV – the new R&S mid-range platform

Touchscreen
                                                               5 x faster
                                                           than any other SA



                     < 0.39 dB
                              ty
                     uncertain
                       to 7 GHz



                                                                         Hz
                                                                     40 M dth
                                                                           i
                                                                    B andw


              75 Year Anniversary, Israel, November 2008
R&S FSV: the next generation mid-range
         industry standard


                              Widest demodulation bandwidth in class
                              Widest demodulation bandwidth in class
                              Best in class dynamic range
                              Best in class dynamic range
                               Best in class measurement uncertainty up to 7 GHz
                               Best in class measurement uncertainty up to 7 GHz
                               Next generation operation: touchscreen
                               Next generation operation: touchscreen
                              The world's fastest spectrum analyzer
                               The world's fastest spectrum analyzer
                              Outstanding price // performance ratio
                              Outstanding price performance ratio




          75 Year Anniversary, Israel, November 2008
R&S FSV: the next generation
         mid-range industry standard

    1       Class leading analysis bandwidth: 40 MHz - >Fit for all wireless
            applications including 802.11n
2           Fastest Analyzer, up to 5 x faster than closest competitor
        3   Best dB/$$ performance and accuracy
            New ways to make operation easy: intuitive graphic operation with
4
            touchscreen
            Seamless transition to next generation analyzers for present FSP
    5       customers with full FSP compatibility: form factor, improved RF, full
            GPIB compatibility, compatible options




                      75 Year Anniversary, Israel, November 2008
R&S FSV:                                                        5
Seamless transition to the next generation
    Designed to prolong the success of the FSP:
    5 Models:       9kHz (20 Hz) to 3.6 GHz, 7 GHz,
                    coming: 13.6 GHz, 30 GHz, 40 GHz,
                    same frequency coverage as FSP
    Measuring functions (CP, ACP, …) as in FSP
    Same form factor
    GPIB compatible to FSP

    Easy one to one replacement protects customer investment in SW or
      systems and makes transition seamlessly possible




                75 Year Anniversary, Israel, November 2008
R&S FSV: Ease of operation                                                   4


Designed for fast and easy operation
SVGA display improves readability and resolution
Touchscreen
 Improved front panel layout and additional hardkeys
On screen keyboard in combination with touchscreen eliminate necessity for
    keyboard / mouse
Additional RF measurements like spectrum emission mask integrated in basic
    instrument
6 traces, more markers
AUTO SET and UNDO/REDO functions




                    75 Year Anniversary, Israel, November 2008
Ease of operation
    4

Fast mode switching via tabs, on screen keyboard, up 6
simultanoeusly active traces and trace wizard, marker
movement via touch




                 75 Year Anniversary, Israel, November 2008
R&S FSV dB/$$                                                        3


 Level uncertainty             <0.39 dB (f < 7 GHz, total, 95%)
 TOI                           > 13 dBm, typ. 17 dBm (f < 3 GHz)
                               > 15 dBm, typ. 19 dBm (3 GHz < f < 7 GHz)
 DANL                          < -150 dBm (1Hz), typ. – 153 dBm
                               (f < 3 GHz, preamp off),
                               < -146 dBm (1Hz), typ. – 149 dBm
                               (f < 7GHz, preamp off)
 Phase Noise                   < -106 dBc @ 10 kHz offset
    (1Hz, CF=1 GHz)            < -115 dBc @ 100 kHz
                               < -134 dBc @ 1 MHz
                               typ. -150 dBc @ 10 MHz




               75 Year Anniversary, Israel, November 2008
R&S FSV dB/$$                                                         3


ACLR Dyn. Range        >70 dB (typ., noise correction off)
   (3GPP)              >74 dB (typ., noise correction on)
1 dB attenuator steps (f < 7 GHz, option; standard: 5 dB)

RBW range                  1 Hz to 10 MHz, 1,2,3,5 steps;
                           Zero span: 20, 28 MHz, 40 MHz (optional)
VBW range                  1 Hz to 10 MHz, 20, 28, 40 MHz
Price range                same as for FSP




                 75 Year Anniversary, Israel, November 2008
R&S FSV Speed
                                                                  2

Fast "conventional" sweep
  => much faster than other spectrum analyzers
FFT with large partial spans for low RBW settings at large span
Fast switching between personalities
GBit Ethernet for fast IQ data readout
Broadband RF Power detector for fast autoranging
Benchmarks:
    Remote control, sweep update: 1000/s, 1 ms/sweep
    Manual operation, sweep update: 500/s, 2 ms/sweep
    Remote CF Tune and query: 15 ms
    Remote Marker Peak: 1.5 ms
    Sweep time, span 10 MHz, 10 Hz RBW, sweep mode AUTO: < 1 s:




                   75 Year Anniversary, Israel, November 2008
R&S FSV Demodulation bandwidth                               1



I/Q Bandwidth: 28 MHz, 40 MHz optional
I/Q Memory:             200 MSamples
16 Bit ADC
Sampling rate: 128 MHz
Hardware resampler allows almost any user defined
   sampling rate
Prepared for digital I/Q in/out via LVDS interface




                75 Year Anniversary, Israel, November 2008
R&S FSV, digital IQ subsystem:                                       1
advantages and user benefits
 Hardware resampler matches sampling rate and required
   bandwidth
     Speeds up demodulation measurements, since no software resampling
     is required
     Record longer time periods by using a bandwidth adapted, reduced
     sampling rate
 28 MHz bandwidth covers all WiMAX bandwidths (MXA : only 25
   MHz) at base unit price
 28 MHz bandwidth does CCDF on 4 carrier WCDMA signals at
   base unit price
 40 MHz bandwidth for full coverage of 802.11n

 200 MS IQ memory for long recording times



                75 Year Anniversary, Israel, November 2008
R&S FSV: the next generation
           mid-range industry standard
        Main MARCOM messages
        Class leading analysis bandwidth: 40 MHz - >Fit for all wireless
    1   applications including 802.11n


2       Fastest Analyzer, up to 5 x faster than closest competitor


    3   Best dB/$$ performance and accuracy

        New ways to make operation easy: intuitive graphic operation with
4       touchscreen

        Seamless transition to next generation analyzers for present FSP
    5   customers with full FSP compatibility: form factor, improved RF, full
        GPIB compatibility, compatible options


                75 Year Anniversary, Israel, November 2008
R&S FSV – Hardware highlights

No YIG filter up to 7 GHz for high level accuracy
No analog resolution filters for high display linearity
All options besides tracking generator, external generator
   control and microwave preamplifiers are user retrofittable
Removable harddrive ( = security option, standard)
Direct path for f < 21 MHz ensure best sensitivity also in the
   audio range: typ – 140 dBm at 9 kHz




                  75 Year Anniversary, Israel, November 2008
R&S FSV – RF concept




          75 Year Anniversary, Israel, November 2008
FSV RF concept:
advantages and user benefits
Main difference: no detoriation by preselecting YIG Filter
Most accurate analyzer to 7 GHz: < 0.39 dB (2 σ) total uncertainty to 7
   GHz
    -> replace power meter for WLAN 802.11a power measurements ,
   satellite montoring applications
No EVM degradation or need for YIG-filter bypass
   -> Other analyzers do not even have an EVM spec above 3.6 GHz!
Direct path from RF input to ADC for best sensitivity at low
   frequencies (F < 21 MHz)




                 75 Year Anniversary, Israel, November 2008
R&S FSV – Available hardware options

Extension of signal analysis bandwidth from 28 to 40 MHz
30 dB electronic attenuator (1 dB steps, to 7 GHz)
15 dB preamplifier up to 7 GHz
Additional interfaces: IF / Video out, Trigger port
OCXO, precision frequency reference
AM/FM demodulator for audio monitoring
Ruggedized housing
Second hard disk (for exchange with removable built-in hard disk)




                   75 Year Anniversary, Israel, November 2008
RS& FSV Available and planned software options
   Application                              FSH          FSL     FSV    FSU   FSQ
   GSM / Edge

   CDMA 2000 / 1xEvDo *

   WCDMA 3GPP incl HSPA

   WLAN 802.11a/b/g/j

   WLAN 802.11n

   WiMax 802.16 / 16e
   WiBRO (OFDM & OFDMA)
   LTE

   General Purpose                                                 *)
   Vector Signal Analysis *


   * : planned options



                    75 Year Anniversary, Israel, November 2008
R&S FSV Available and planned software options
    Application                             FSH          FSL      FSV   FSU   FSQ
    Analog Modulation Analyzer


    Noise figure measurements*

    Phase noise measurements*

    Power sensor support




    * : planned options



                     75 Year Anniversary, Israel, November 2008
      R&S FSV Positioning

Specification              FSL                                  FSV             FSU/Q
TOI                     > 10 dBm                            > 13/15 dBm       > 20 dBm
DANL @ 1 GHz           <- 140 dBm                           <- 151 dBm       <- 155 dBm
Phase noise
@ 10 kHz              - 103 dBc        - 106 dBc                               - 133 dBc
@ 1 MHz               - 120 dBc        - 138 dBc                               - 146 dBc
RBW range          1 Hz to 10 MHz   1 Hz to 10 MHz                          1 Hz to 50 MHz
                  28 MHz Zero Span 40 MHz Zero Span
Best level              0.5 dB          0.28 dB                                 0.3 dB
uncertainty
Signal analysis           28 MHz                                28/40 MHz    28/120 MHz
bandwidth



                   75 Year Anniversary, Israel, November 2008
Thank You for Your Attention
                           Any Questions?




    75 Year Anniversary, Israel, November 2008

				
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