M-Ary Orthogonal DS-Rake Receiver Technology Research

In mobile communication, due to user's random mobility, the received multipath component's quantity, size (range), delay (arrival time), phase are random variables, so the synthetic vector is also a random variable, which lead to inter-symbol interference and fading, seriously affected the quality of communication. RAKE receiver can make use of these multi-path signals by separating and merging them, which greatly improve the quality of communications systems.RAKE receiver can be realized as relevant receiver and matched filtering receiver, relevant receiver is more complicated than matched filtering receiver. In this paper, I introduced a Direct Sequence Spread M-ray orthogonal spread spectrum matched filter RAKE receiver system; the system's implementation is much easier than relevant receiver.This paper analyzed and researched the key technologies of matched filtering method, including: the performance of M-ray orthogonal analysis, the characteristics of Rayleigh fading and RAKE receiver principle, these points are the causes of this article generated.Next, the characteristics of the spreading codes is studied. First of all, analyzed the commonly used spreading code, then improved the spreading codes. In improving the characteristics of spreading codes, the paper try to use an easy way to analyze its properties, for various spreading codes, I did a lot of data statistics analysis and simulation.Finally, I studied the RAKE receiver matched filtering method. Introduced the system structure, the originator and the working principle of all functional modules, including the number of matched filter, fast Hadamard transform.