Research Of Equalization Algorithm In Continuous Wave Communication System With Code Division Multiplexing

Ground beam forming(GBBF) technology is a new kind of satellite mobile communication system, it could reduce the weight, size, cost, power consumption and the complexity of satellite payload; making satellites’ deployment, development and maintenance easier and cheaper.Continuous wave code division multiplexing technology is used in GBBF system’s feed link. It multiplexes the feeder antenna signals’ amplitude directly with the orthogonal codes, which could save the feeder link bandwidth. compared with FDM and TDM, CDM signals occupies the same band in the same time slot; the correlation properties of the feed link signals could be better maintained in this way.However, the link frequency selective fading channel could destroy the orthogonality of the CDM codes, leading to serious signal interference and damage the correlation properties of the feed link signals. Real-time changed Weather conditions may also affect the feed link signals. equalization techniques could compensate the channel’s frequency selective fading effects, and could adaptively tracking cariations in channel characteristics, ensuring the transmission of the feed link signals.In order to enhance the performance of GBBF system. This paper is mainly about the application of different equalization algorithm in continuous wave communication systems with code division multiplexing. Some typical time domain equalization as well as some frequency domain equalization algorithm were compared in this paper. This paper use power leakage and amplitude and phase coherence to measure the performance of the continuous wave communication system. This paper also proposed a simplified LMS adaptive equalization algorithm and realize it with VHDL language programming in ISE development environment.This paper also proposed a symbol-level adaptive equalization algorithm based on LMS; simulation results showed that compared with traditional chip-level equalization algorithm, this symbol-level algorithm could improve the throughput of the equalization algorithm, could indirectly improve the convergence rate of equalization algorithm and improve the receiver’s BER performance.