Wireless Propagation by t858OR

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									Wireless Propagation




         Mentor: David Browne


         Valerie Bick     Eric Seidler
         Katherine Kuan   Haleh Tabrizi
UnWiReD Lab

              -   Located in the Engineering IV
                  Building, 5th Floor
              -   Research physical layer
                  wireless communications:
                        coded modulation
                        demodulation
                        synchronization
                        channel characterization
                        equalization
              -   Grad students Jared Dulmage,
                  Daniel Liu, Heechoon Lee,
                  Michael Samuel
Background

   Omni-directional
    antennas are NOT
    energy efficient in
    sparsely connected
    networks
   Attempting new
    network design using
    directional antennas for
    wilderness deployment
Background

   Challenges associated with directional
    antennas
    –   Assembling network (need alignment)
    –   Nodes don’t know where their neighbors are
        located
    –   Alternative pathways other than line of sight may
        exist
    –   Find algorithm to allow quick and efficient
        assembly of the network
Wireless Propagation Project
Wireless Propagation Project
Individual Projects

   Automatic Gain Control
   Wideband Radio Synthesizer
    Programming
   Signal Processing
   Antenna Characterization and Robotics
   Local and Remote Interface
System Overview
                           Summer 2006: Wireless Prpogation with David Browne
                           Automatic Gain Control: Simplified Problem Description with Diagram
                           -Dynamically control the gain levels of the eMonitoring and NovaSource radios via MATLAB
                           for the purpose of getting the full range of sensitivity out of the Acquiris digitzer card
                           -System must also keep track of original signal strengths, see circles (why?)
                           -Eventually, gain of the digitizer card will be adjusted dynamically via Linux (?)




                       ?
                               RX
              TX
             2.4 GHz




                                                                                          70MHz
                                                          eMonitoring                                       Acquiris A/D
NovaSource                                               (UCLA) radio                                        converter




                                                     MaxStream Radio                                           MATLAB
MaxStream
Automatic Gain Control




          Eric and Kat
Automatic Gain Control
                            Summer 2006: Wireless Prpogation with David Browne
                            Automatic Gain Control: Simplified Problem Description with Diagram
                            -Dynamically control the gain levels of the eMonitoring and NovaSource radios via MATLAB
                            for the purpose of getting the full range of sensitivity out of the Acquiris digitzer card
                            -System must also keep track of original signal strengths, see circles (why?)
                            -Eventually, gain of the digitizer card will be adjusted dynamically via Linux (?)




                        ?                                                        ex: signal too weak
                                RX
               TX
              2.4 GHz




                                                                                           70MHz
                                                           eMonitoring                                       Acquiris A/D
 NovaSource                                               (UCLA) radio                                        converter
Boost Gain                                        Boost Gain                                         Gain or
                                                                                                   Attenuation


                                                      MaxStream Radio                                           MATLAB
  MaxStream
Automatic Gain Control
                                                             Summer 2006: Wireless Prpogation with David Browne
                                                             Automatic Gain Control: Simplified Problem Description with Diagram
                                                             -Dynamically control the gain levels of the eMonitoring and NovaSource radios via MATLAB
                                                             for the purpose of getting the full range of sensitivity out of the Acquiris digitzer card
                                                             -System must also keep track of original signal strengths, see circles (why?)
                                                             -Eventually, gain of the digitizer card will be adjusted dynamically via Linux (?)
                  1

                 0.9

                 0.8
                                                      ?
                                                                 RX
                                         TX
                 0.7                    2.4 GHz
Signal Volatge




                 0.6

                 0.5                                                                        eMonitoring                     70MHz
                                                                                                                                              Acquiris A/D
                       NovaSource                                                          (UCLA) radio                                        converter
                 0.4

                 0.3

                 0.2

                 0.1                                                                   MaxStream Radio                                           MATLAB
                       MaxStream
                  0
                   0                2             4   6      8                    10                     12
                                                      Time
Automatic Gain Control

   Used PC to communicate to MaxStream
    radio modem
   Communicated b/t 2 radio modems
   Used MaxStream radios to send commands
    to NovaSource radio
   Worked with Acqiris Digitizer and Function
    Generator
   Setup simplified feedback loop
Wideband Radio Synthesizer
      Programming




            Kat
Wideband Radio Synthesizer
                           Summer 2006: Wireless Prpogation with David Browne
                           Automatic Gain Control: Simplified Problem Description with Diagram
                           -Dynamically control the gain levels of the eMonitoring and NovaSource radios via MATLAB
                           for the purpose of getting the full range of sensitivity out of the Acquiris digitzer card
                           -System must also keep track of original signal strengths, see circles (why?)
                           -Eventually, gain of the digitizer card will be adjusted dynamically via Linux (?)




                       ?
                               RX
              TX
             2.4 GHz




                                                                                          70MHz
                                                          eMonitoring                                       Acquiris A/D
NovaSource                                               (UCLA) radio                                        converter




                                                     MaxStream Radio                                           MATLAB
 MaxStream
Wideband Radio Synthesizer

   Adapt parallel port interface to allow node to program
    synthesizers on the fly
   Rewire parallel port
   Learn synthesizer programming from Linux
   Integrate power sensing into Matlab
Signal Processing




        Haleh
Signal Processing

     Fourier processing technique
     Develop a data archival format that is
      efficient
     Implement in Matlab
Signal Processing
                            Summer 2006: Wireless Prpogation with David Browne
                            Automatic Gain Control: Simplified Problem Description with Diagram
                            -Dynamically control the gain levels of the eMonitoring and NovaSource radios via MATLAB
                            for the purpose of getting the full range of sensitivity out of the Acquiris digitzer card
                            -System must also keep track of original signal strengths, see circles (why?)
                            -Eventually, gain of the digitizer card will be adjusted dynamically via Linux (?)




                        ?
                                RX
               TX
              2.4 GHz




                                                                                           70MHz
                                                           eMonitoring                                       Acquiris A/D
 NovaSource                                               (UCLA) radio                                        converter




                                                      MaxStream Radio                                           MATLAB
 MaxStream
Signal Processing

   Communicate with the
    Nova Source

   Write Matlab code to
    generate signals with
    certain frequencies

   See the results in a
    spectrum analyzer
Signal Processing
                            Summer 2006: Wireless Prpogation with David Browne
                            Automatic Gain Control: Simplified Problem Description with Diagram
                            -Dynamically control the gain levels of the eMonitoring and NovaSource radios via MATLAB
                            for the purpose of getting the full range of sensitivity out of the Acquiris digitzer card
                            -System must also keep track of original signal strengths, see circles (why?)
                            -Eventually, gain of the digitizer card will be adjusted dynamically via Linux (?)




                        ?
                                RX
               TX
              2.4 GHz




                                                                                           70MHz
                                                           eMonitoring                                       Acquiris A/D
 NovaSource                                               (UCLA) radio                                        converter




                                                      MaxStream Radio                                           MATLAB
 MaxStream
Signal Processing

   Generate a sample                 4
                                                                 70MHz signal, sampled at a rate of 500MHz


                                      2

    signal of 70MHz


                          amplitude
                                      0

                                      -2

                                      -4
                                           0   0.2   0.4   0.6         0.8            1            1.2       1.4   1.6   1.8           2
                                                                                    time                                              -6
                                                                                                                               x 10
                                                                                    noise

   Generate White                    4

                                      2

                          amplitude
    Gaussian Noise                    0

                                      -2

                                      -4
                                           0   0.2   0.4   0.6         0.8            1            1.2       1.4   1.6   1.8           2
                                                                                    time                                              -6
                                                                                                                               x 10
                                                                        noise plus the original signal
                                      4


   Add the two signals               2
                          amplitude




                                      0

    (Time Domain)                     -2

                                      -4
                                           0   0.2   0.4   0.6         0.8            1            1.2       1.4   1.6   1.8           2
                                                                                    time                                              -6
                                                                                                                               x 10
Signal Processing

   Transform the signal                      100
                                                                                fft of the 70MHz signal




    with AWGN to the                            50

                                                 0




                             magnitude (dB)
                                               -50


    frequency domain to                       -100

                                              -150




    obtain the original
                                              -200

                                              -250

                                              -300
                                                 -2.5   -2   -1.5   -1   -0.5             0               0.5   1   1.5   2      2.5


    signal.                                                                           frequency



                                                                          fft of the 70MHz signal with noise
                                                                                                                              x 10
                                                                                                                                     8




                                              100



   Calculate the original                      50

                                                 0
                             magnitude (dB)




    signal and noise
                                               -50

                                              -100

                                              -150



    powers                                    -200

                                              -250

                                              -300
                                                 -2.5   -2   -1.5   -1   -0.5             0               0.5   1   1.5   2      2.5


   Calculate the SNR                                                                 frequency
                                                                                                                              x 10
                                                                                                                                     8
Antenna Characterization and
         Robotics




             Eric
Antenna Characterization and Robotics

   Install new antennas
    and characterize
    antennas
   Mechanics
    –   Mount new antennas on
        robots
    –   Secure robots for
        transport
Antenna Characterization and Robotics

   Update robot control
    software in Matlab
   Electrical
    –   Standardize wiring
    –   Provide power to WB
        Radio via Node
    –   Enable battery power of
        pelican node
    –   Mount battery charge
        indicators on batteries
Local and Remote Interface




            Valerie
Local and Remote Interface
                           Summer 2006: Wireless Prpogation with David Browne
                           Automatic Gain Control: Simplified Problem Description with Diagram
                           -Dynamically control the gain levels of the eMonitoring and NovaSource radios via MATLAB
                           for the purpose of getting the full range of sensitivity out of the Acquiris digitzer card
                           -System must also keep track of original signal strengths, see circles (why?)
                           -Eventually, gain of the digitizer card will be adjusted dynamically via Linux (?)




                       ?
                               RX
              TX
             2.4 GHz




                                                                                          70MHz
                                                          eMonitoring                                       Acquiris A/D
NovaSource                                               (UCLA) radio                                        converter




                                                     MaxStream Radio                                           MATLAB
 MaxStream
Local and Remote Interface

   Develop graphical user
    interface
   GPS interface with
    Google Earth
   Real time plots
   Experimental control
   Remote interface
GPS


      GPS


            Serial


                     GPSD


                            Matlab


                                     User
GPS

         Collect GPS
          data outside
          Ackerman
          Student Union
         Begin writing
          code to process
          GPS data
     The End!




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