Abstract: A transmitter and method for processing a digital data stream is disclosed. The transmitter includes a mode controller that selects one of a first mode or a second mode such that the transmitter operates with a first modulation scheme in the first mode and a second modulation scheme in the second mode. A receiver and method for processing a modulated carrier is further disclosed. The receiver also includes a mode controller such that the receiver operates with a first modulation scheme in a first mode and a second modulation scheme in a second mode. Common functions/modules of the transmitter and receiver are used in both the first and second modes.

Abstract: A method is provided for determining the Doppler frequency shift that occurs in the reception of a communication signal when the relative velocity between the transmitted and receiver is unknown. By estimating the channel characteristics and measuring the channel response to known transmitted data bits, a measure of the Doppler frequency is determined according to the method of the invention. In particular, a good estimate of the Doppler frequency shift is obtained based on a second order statistic of the fading process for the channel response to the known transmitted data bits. The approach is simple and general. It applies for any system such as WCDMA and CDMA 2000 when Doppler frequency is needed.

Abstract: A method for adjusting the power of a probe signal to be transmitted by user equipment to system equipment of a wireless communication system. The power of the probe signal is adjusted based on information received by the user equipment from the system equipment. The information is a local mean of RSSI at the system equipment. The adjusted probe signal is transmitted and thus has an increased likelihood of being detected by the system equipment. Also, the power available for transmitting the probe signal is used more efficiently when the probe signal is adjusted in accordance with the local mean information received by the user equipment from system equipment of the wireless communication system.