Title :
IMD compensation for CDMA through FEC coding and nonlinearity recovery technique for optical fiber feeder system
Author :
Yaqub, Raziq P. ; Nakagawa
Author_Institution :
DDI Corp., Japan
Abstract :
Optical feeding between base stations (BS) and radio network control (RNC), proposed in this paper, is an efficient technique for third generation wideband CDMA mobile communication systems. The proposed technique provides the compensation to the intermodulation distortion (IMD) instituted by both the power amplifier (an electrical component) and the laser diode (an optical component). This IMD can impose strong limitations on CDMA and deteriorate system performance. In this paper IMD compensation is proposed through unification of FEC codes and a post nonlinearity recovery block (PNRB). System performance is evaluated through calculating the transfer functions of FEC codes, laser diode and PNRB. The transfer functions of the FEC codes are calculated by using the flow graph rules, and of the laser diode and PNRB through Volterra kernels. Performance of the PNRB alone for narrowband CDMA signals was sought in our previous work (Pervez and Nakagawa, 1996), whereas performance of PNRB combined with digital coding protection to compensate for the nonlinearities of the laser diode (LD) and power amplifier (PA) for wideband CDMA is pursued here
Keywords :
cellular radio; code division multiple access; forward error correction; intermodulation distortion; nonlinear network analysis; nonlinear optics; optical fibre communication; power amplifiers; radiofrequency amplifiers; semiconductor lasers; telecommunication control; transfer functions; CDMA; FEC coding; IMD; IMD compensation; PNRB; Volterra kernels; base stations; digital coding protection; flow graph rules; intermodulation distortion; laser diode; narrowband CDMA signals; nonlinearity recovery technique; optical fiber feeder system; post nonlinearity recovery block; power amplifier; radio network control; third generation mobile systems; transfer functions; wideband CDMA mobile communication systems; Broadband amplifiers; Diode lasers; Multiaccess communication; Optical amplifiers; Optical distortion; Optical fiber networks; Power amplifiers; Stimulated emission; System performance; Transfer functions;
Conference_Titel :
Computers and Communications, 1999. Proceedings. IEEE International Symposium on
Conference_Location :
Red Sea
Print_ISBN :
0-7695-0250-4
DOI :
10.1109/ISCC.1999.780925
