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Radio-on-Fiber Transport Systems

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Radio-on-Fiber Transport Systems Powered By Docstoc
					                Radio-on-Fiber
               Transport Systems
            Hai-Han Lu and Ardhendu Sekhar Patra
                          E-mail:hhlu@ntut.edu.tw




National Taipei University of Technology
                 Institute of Electro-Optical Engineering
       Fiber Optical Communication Laboratory
                      Introduction

  Radio-on-Fiber (ROF) System

  Radio-on-Fiber Intelligence Transport Systems

  External Light Injection Technique

  Conclusion



Fiber Optical Communication Laboratory
                 Introduction-ROF

 Radio-on-fiber systems are expected to play an
 important role in broad-band wire/wireless
 convergence networks.

 Radio-on-fiber, the integration of wireless and
 optical systems, is a powerful solution for
 increasing the capacity and mobility as well as
 decreasing costs in environments.



Fiber Optical Communication Laboratory
  Radio-on-Fiber                                 uplink
          antenna
                                                  O/E
                                      Diplexer                  In / out

     Fiber                                        O/E
                 Base Station (BS)
          .…….



                                           Base Station (BS)
                        .….

                                                 downlink
                                          Advantages:
Control                                      Combining fiber optics and
Station                                      wireless radio communication
                                             systems.
 (CS)
                                             Possess large bandwidth and
                                             low attenuation characteristic.


                 Base Station (BS)
 Fiber Optical Communication Laboratory
         Macrocell and Microcells
   Macrocell                             Macrocell < 300m
                                         Microcell < 20m




                         Light pole mounted microcells


Fiber Optical Communication Laboratory
            Radio-on-Fiber System
         Central Station
    Light         O/E
   Source       Modulator
      Source        E/O                                      Optical Fiber
      Service     Detector

                                             Base Station
                       Wavelength division            Amp.
                           Multiplexer
                         or star coupler       O/E
                                                                        ITS
                                               E/O
                                                     Amp.



  FTTH
                              Mobile         FWA
Fiber Optical Communication Laboratory
                      Introduction

   Radio-on-Fiber (ROF) System

   Radio-on-Fiber Intelligence Transport Systems

   External Light Injection Technique

   Conclusion


Fiber Optical Communication Laboratory
Intelligence Transport System (ITS) Concept

                                 People

                                 Data
                          Telecommunications
                               Technology
             Roadway                               Vehicle




      Dramatic improvement in safety, transportation efficiency,
                amenity, and environment protection.

  Fiber Optical Communication Laboratory
        DSRC                                                        DSRC
                                  Cellular phone,
                                     PHS,etc.




  Radio         Optical        Radio        Optical          Radio      Optical


                Optical transmission network                         Optical fiber


Optical                                     Multiplex/demultiplex
transmission/                                    technology
distribution        Optical-radio
                    conversion device                                   DSRC service 1
                    technology
                                                    +                   DSRC service 2

                 Optical       Radio
                                                                        Cellular phone,
                                                                        PHS,etc.

Fiber Optical Communication Laboratory
              Mobile CATV concept
                     CATV center                      Other network

                                 RoF multiple service transmission




                      Access point                      Tap off



                                                         Set-top-box


   P                                                              TV
                                       Seamless
                                                                  PC

   Vehicles                                                  Telephone
              Mobile CATV


Fiber Optical Communication Laboratory
                      Introduction

  Radio-on-Fiber (ROF) System

  Radio-on-Fiber Intelligence Transport Systems

  External Light Injection Technique

  Conclusion


Fiber Optical Communication Laboratory
Introduction-External Light Injection

   External light injection technique has been used
   in ROF transport systems to improve system
   performance.

   The injection-locked lasers can be enhanced with
   a large bandwidth, and system has better
   transmission performance.



  Fiber Optical Communication Laboratory
Injection-Locked Semiconductor Lasers
                                             Isolator
                                                          Master
 Coupler                       PC
                                                          Laser
                   Slave
& Isolator         Laser           Coupler
                                                OSA
                                                 OSA
          Optical Circulator
 Slave         2      1           Master
 Laser      PC                    Laser
                     3                        Optical
                                             Circulator
                 OSA
  Fiber Optical Communication Laboratory
Injection-Locked Semiconductor Lasers
                                              Injection power:-3dBm 0dBm 3dBm
                          10
 Relative Response (dB)


                          5
                          0

                          -5
                          -10
                                    Free running
                          -15

                          -20
                          -25
                          -30

                          -35
                                0         5           10      15       20       25
                                                   Frequency (GHz)
   Fiber Optical Communication Laboratory
  Injection-Locked Semiconductor Lasers


                                                                     SMSR > 47dB



10.0                                                  10.0
dB/D                                                  dB/D




 1530.00             1545.00 nm   3.00 nm/D 1560.00    1530.00   1545.00 nm   3.00 nm/D 1560.00

The optical spectrum for FP LD without The optical spectrum for FP LD with
light injection.                       light injection.


           Fiber Optical Communication Laboratory
 Injection-Locked Semiconductor Lasers


     SMSR = 44dB                                          SMSR = 50dB




1535.00             1545.00 nm   2.00 nm/D 1555.00   1535.00        1545.00 nm   2.00 nm/D 1555.00

   The optical spectrum for DFB LD                      The optical spectrum for DFB LD
   without light injection.                             with light injection.


          Fiber Optical Communication Laboratory
Injection-Locked Semiconductor Lasers
  The injection-locking techniques has many
  advantages:
       Enhance laser bandwidth
       Reduce nonlinearities
       Reduce chirp for direct current digital modulation
       Increase of the bandwidth-distance product
       Increase in dynamic range
       Lock an uncooled laser


  Fiber Optical Communication Laboratory
External Light Injection Technique for SOA

                                                 Isolator
                    Polarization
                     Controller



          SOA
                                                            Light Injection
                                   Coupler


                                                    3 dB
                  Gain (dB)




                                        Po,sat

                          Output signal power (dBm)
  Fiber Optical Communication Laboratory
         Broadband ASE light source
 The EDFA has been widely used in fiber network
 systems due to its ASE output power.

 The high-power ASE from an EDFA can be
 efficiently divided into many channels by using a
 DEMUX or BPFs.


            λ1
            λ2                       Broadband
            λ3                       ASE Source
            λ4              WDM
                           DEMUX




Fiber Optical Communication Laboratory
ASE can be efficiently divided into many
  channels by using a FBG and OC

                                         FBG1 (FBG3)

                    λ1 (λ3)
          -5 dBm

                                 OC              Broadband
                                                 ASE Source
                    λ2 (λ4)
          -5 dBm

                                         FBG2 (FBG4)




Fiber Optical Communication Laboratory
           Broadband ASE Spectrum


                                         1552.4 nm




                        1540 nm                      1560 nm




Fiber Optical Communication Laboratory
                      Introduction

 Radio-on-Fiber (ROF) System

 Radio-on-Fiber Intelligence Transport Systems

 External Light Injection Technique

 Conclusion



Fiber Optical Communication Laboratory
                        Conclusion

Radio-on-fiber (ROF) systems are used to enhance the radio
coverage of wireless applications and provide broadband
services.
ROF transport systems are suitable for the long-haul
microwave optical link.
There are several ways to improve the performances of radio-
on-fiber systems.
   External light injection – Laser and SOA
Fiber-to-the-Home


Fiber Optical Communication Laboratory
       Fiber




FTTB                                        WLAN


   Fiber Optical Communication Laboratory
                                 Publications List
[1] H. H. Lu, W. I. Lin, C. Y. Lee, S. J. Tzeng, and Y. W. Chuang, “A Full-Duplex Radio-on-PCF Transport
    System”, Accepted, IEEE Photonics Technology Letters, 2007. (SCI) (NTUT and NSC 95-2221-E-
    027-095-MY3)
[2] H. H. Lu, S. J. Tzeng, Y. W. Chuang, Y. C. Chi, and C. W. Liao, “Bidirectional Radio-over-DWDM
    Transport Systems Based on Injection-Locked VCSELs and Optoelectronic Feedback Techniques”, vol.
    19, pp. 315-317, IEEE Photonics Technology Letters, 2007. (SCI) (NTUT and NSC 95-2221-E-027-
    095-MY3)
[3] H. H. Lu, C. L. Ying, W. I. Lin, Y. W. Chuang, Y. C. Chi, and S. J. Tzeng, “CATV/ROF Transport
    Systems Based on Light Injection/Optoelectronic Feedback Techniques and Photonic Crystal Fiber”, vol.
    273, pp. 389-393, Optics Communications, 2007. (SCI) (NTUT and NSC 95-2221-E-027-095-MY3)
[4] H. H. Lu, H. L. Ma, Y. W. Chuang, Y. C. Chi, C. W. Liao, and H. C. Peng, “Employing Injection-
    Locked Fabry-Perot Laser Diodes to Improve Bidirectional WDM-PON Performances”, vol. 270, pp.
    211-216, Optics Communications, 2007. (SCI) (NSC 95-2221-E-027-095-MY3)
[5] H. H. Lu, Y. W. Chuang, G. L. Chen, C. W. Liao, and Y. C. Chi, “Fiber-Optical Cable Television
    System Performance Improvement Employing Light Injection and Optoelectronic Feedback Techniques”,
    vol. 18, pp. 1789-1791, IEEE Photonics Technology Letters, 2006. (SCI) (NSC 94-2215-E-027-001)
[6] H. H. Lu, W. S. Tsai, H. C. Peng, and Y. J. Ji, “A Comparison between Optical SSB Transmitter/Filter in
    a Full-Duplex Radio-on-Fiber Transport System”, vol. 9, pp. 649-651, IEEE Communications Letters,
    2005. (SCI)
[7] H. H. Lu, W. S. Tsai, W. J. Wang, and Y. L. Lui, “Employing Double External Light Injection
    Techniques to Improve Radio-on-DWDM System Performance”, vol. 17, pp. 672-674, IEEE Photonics
    Technology Letters, 2005. (SCI) (NSC 93-2215-E-027-003)
[8] H. H. Lu, J. W. Liaw, Y. J. Ji, W. L. Tsai, and Y. S. Lee, “Transmission Improvement of VCSELs at
    4×2.5 Gbit/s under SOA with External Light Injection Technique”, vol. 44, pp. 020503-1 - 020503-2,
    Optical Engineering, 2005. (SCI)

     Fiber Optical Communication Laboratory
                                Publications List
[9] H. H. Lu, W. S. Tsai, C. Y. Chen, and H. C. Peng, “CATV/Radio-on-Fiber Transport Systems Based on
    EAM and Optical SSB Modulation Technique”, vol. 16, pp. 2565-2567, IEEE Photonics Technology
    Letters, 2004. (SCI)
[10] H. H. Lu, J. W. Liaw, Y. J. Ji, W. L. Tsai, and Y. S. Lee, “A-10 Gbit/s WDM transport system based
    on VCSELs and SOA with external light injection technique”, vol. 1, pp. 228-232, IEICE Electronics
    Express, 2004. (SCI)
[11] H. H. Lu, W. S. Tsai, Y. J. Ji, J. W. Liaw, Y. S. Lee, and W. L. Tsai, “Employing Optical Optical SSB
     Modulation Technique in a Full-Duplex Radio-on-Fiber Transport System”, IEICE Transactions on
     Communications, vol. E87-B, pp. 3150-3154, 2004. (SCI) (NSC 92-2215-E-027-006)
[12] H. H. Lu, P. C. Lai, and W. S. Tsai, “Radio on Multimode Fiber Systems Based on VCSELs and
    External Light Injection Technique”, IEEE Photonics Technology Letters, vol. 16, pp. 1215-1217,
    2004. (SCI) (NSC 92-2622-E-027-022-CC3)
[13] H. H. Lu, S. J. Tzeng, Y. H. Su, and Y. C. Lin, “Employing Double External Light Injection
    Techniques to Improve Radio-on-Fiber Systems Performance”, Optics Communications, vol. 230, pp.
    185-190, 2004. (SCI) (NSC 92-2215-E-027-006)
[14] H. H. Lu, Y. C. Lin, Y. H. Su, and H. S. Su, “A Radio-on-Fiber Intelligence Transport System Based
    on Electroabsorption Modulator and Semiconductor Optical Amplifier”, IEEE Photonics Technology
    Letters, vol. 16, pp. 251-253, 2004. (SCI) (NSC 92-2215-E-027-006)
[15] H. H. Lu, H. H. Huang, H. S. Su, and M. C. Wang, “Fiber Optical CATV System-Performance
    Improvement by Using External Light-Injection Technique”, IEEE Photonics Technology Letters, vol.
    15, pp. 1017-1019, 2003. (SCI) (NSC 91-2215-E-027-001)
[16] H. H. Lu, H. S. Su, M. C. Wang, and H. H. Huang, “Improved Performance of an Externally
    Modulated System with External Light Injection Technique”, Optical Engineering, vol. 42, pp. 1180-
    1181, 2003. (SCI) (NSC 91-2215-E-027-001)


    Fiber Optical Communication Laboratory
   Thanks for Your Attention



Fiber Optical Communication Laboratory

				
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