Patent ID: 6816542
Filing Date: 2004-11-09
Classification: H04B

Abstract:
A direct sequence CDMA receiver for performing despreading of received data based on a delay profile produced from said received data, comprising:analog/digital conversion means for sampling at twice the chip rate a baseband signal obtained by demodulating a signal received from an antenna; a matched filter for finding correlation values between received data that has been sampled by said analog/digital conversion means and a spreading code, while shifting said received data in time; a delay profile production means for interpolating correlation values found by said matched filter and finding said delay profile from the interpolated correlation values; timing detection means for selecting, in descending order of size, delay profiles found by said delay profile production means to extract each timing; despread processing means for interpolating a spreading code to synchronize with timing signals detected by said timing detection means and using these interpolated values to carry out despreading of received data; and mixing means for subjecting signals that have undergone despreading by said despreader to RAKE/diversity mixing to obtain data.