TONE DETECTION USING A CDMA RECEIVER

摘要

A code division multiple access (CDMA) receiver (100) can detect the presence of a GSM tone-based signal by programming the digital filter's tap weights to correlate with a GSM FCCH signal (208). If the correlation between the values of the tap weights and a received signal satisfies a threshold, the receiver produces an indication that a GSM signal is present (212). Post-processing can be performed on the output of the digital filter to improve signal detection based on the determination of the correlation of the received signal with the digital filter, the determination of the corresponding power value, the determination of the signal strength; and the estimation of the frequency offset.