Patent ID: 6263011
Filing Date: 2001-07-17
Classification: H04B,H04L

Abstract:
A receiver in a spread spectrum communication system for receiving a spread spectrum signal having a modulated PN code, the receiver comprising:an analog-to-digital converter for sampling an input signal in synchronization with a first clock signal, and generating a sampled signal, said first clock signal having n times a frequency of a chip clock signal, where n is a positive integer;a counter for counting a number of clocks of the first clock signal to generate a selection signal;a pseudonoise code generator for generating a substantially replica pseudonoise code signal in synchronization with a second clock signal having the frequency of the chip clock signal;a memory for storing the sampled signals in synchronization with the second clock signal;a selector for selecting one of the sampled signals stored in the memory in response to the selection signal;a demodulator for demodulating a modulated pseudonoise code signal from the sampled signal;an accumulator for accumulating outputs of the demodulator during a cycle of the second clock signal to generate an accumulated acquisition value; anda comparator for comparing the accumulated acquisition value with a threshold value, generating an acquisition success signal if the accumulated acquisition value is greater than the threshold value, and generating a hold signal if the accumulated acquisition value is less than the threshold value,wherein said pseudonoise code generator receives the hold signal from the comparator and delays a phase of the substantially replica pseudonoise code signal by a cycle of the chip clock signal.