PREAMBLE DETECTION AND DATA RATE CONTROL IN A UMTS SYSTEM

摘要

A receiver system determines a current preamble threshold and a current preamble metric and determines whether a preamble is detected. If a preamble is detected, the receiver determines whether an earlier preamble has been detected in an earlier time slot having a common time slot interlace index, and resolves multiple detections of a preamble based on at least one of the current preamble and an old preamble thresholds, the current and an old preamble metrics. The receiver decodes data following the selected preamble and determines the CRC of the decoded data. If a CRC failure is detected, th e receiver determines a new current preamble threshold. The new current preamb le threshold is larger than the current preamble threshold. If the current preamble metric is larger than the new current preamble threshold, the receiver determines the CRC failure as an actual CRC failure, otherwise as a false CRC failure.