Patent ID: 6700923
Filing Date: 2004-03-02
Classification: H04B

Abstract:
A spread spectrum receiver comprising a block former coupled to receive samples of a spread spectrum waveform, said samples being sampled at a specified chip rate, said block former also being coupled to a memory and operative to store a block of data therein;a gradient calculation module coupled to said memory and to a tap-weight vector calculation module, said gradient calculation module is operative to receive said data block from said memory and a tap weight vector from said tap weight vector calculation module, said gradient calculation module further being operative to compute a gradient vector with respect to an error function with respect to said tap weight vector; a search direction calculation module coupled to receive a gradient vector from said gradient calculation module and coupled to receive a previous search direction via a feedback path, said search direction calculation module operative to compute a search direction as a function of said previous search direction and the two most recently computed gradient vectors; a stepsize calculation module coupled to said memory, and to said tap weight vector calculation module, said stepsize calculation unit operative to compute a step size according to a prespecified criterion; a tap-weight vector calculation module coupled to receive input from said search direction calculation module and said step size calculation module, and a previous tap weight vector via a feedback path, said tap weight vector calculation module operative to compute a subsequent search direction as a function of said previous tap weight vector, said step size and said previous tap weight vector to produce an updating rule; and an output module operative to couple a linear combination of said tap weight vector with a selected set of said samples of said spread spectrum waveform to produce a block of output symbol values.