Abstract: A rate determination unit and methods for use in a receiver in a communication system that is adapted to receive communications at a plurality of different data rates is disclosed. The rate determination unit is configured to receive an encoded signal and determine the encoded signal's data rate without first requiring decoding of the encoded signal. In a preferred embodiment, the rate determination unit includes a plurality of hypothesis units and a hypothesis analyzer. Each hypothesis unit is arranged to determine a hypothesis value for a frame of the encoded signal at an associated one of the data rates. The hypothesis analyzer is arranged to compare selected hypothesis values, determine the frame data rate based on such comparisons, and output a rate indication signal based on the determined frame data rate.

Abstract: Reverse channel circuitry for CDMA based mobile stations which allows carrier phase offsets to be implemented at baseband, thereby eliminating the need for multiple quadrature modulators and excessive D/A converters. In addition, just four baseband filters, two using scaled coefficients and the other two unscaled coefficients, are time multiplexed to produce in-phase and quadrature terms. The invention can lead to a significant savings in hardware and be a valuable tool in implementing multiple code channels with different carrier phase offsets.