Motorola Corporation

Motorola Mobility LLC

Nokia Solutions and Networks Oy

Robert Stephens

Roy Yang

Andrew Tomerlin

Asad U Aman

Raghunath Hariharan

Achieving phase synchronization in single frequency networks may be useful in various communication systems. For example, the use of synchronous Ethernet, timing over packet, and radio interface based synchronization (RIBS) may be applied in mobile and/or data communication networks. Certain embodiments improve phase accuracy using a hybrid synchronization method beyond standard RIBS and clustering carriers using the same transmission waveforms across carriers. Certain embodiments also select a master transmission point to maximize the signal quality of the composite waveforms in a cluster.

Method and apparatus for synchronization

A technique for decreasing noise and interference in an uplink of a wireless communication system includes detecting, at a serving base station, noise and interference levels above a threshold. In response to the detecting, a noise and interference measurement frame is scheduled that includes respective allocated portions for respective active subscriber stations and respective unallocated portions that are adjacent to the respective allocated portions and are not allocated to one of the respective active subscriber stations. The respective allocated portions and the respective unallocated portions are configured in a selected pattern in the noise and interference measurement frame. The respective noise and interference levels are determined, at the serving base station, in the respective unallocated portions of the noise and interference measurement frame. One or more rogue subscriber stations, included in the respective active subscriber stations, are then identified based on the respective noise and interference levels associated with the respective active subscriber stations. When it is ambiguous as to whether a subscriber station is a rogue subscriber station, additional noise and interference measurement frames may be scheduled to resolve the ambiguity.

Techniques for reducing noise and interference in wireless communication systems

A predistortion linear power amplifier utilizes several predistortion computation engines to receive a first carrier signal. The predistortion computation engines also receive input from a predistortion algorithm engine. The predistortion algorithm engine receives its data from a predistortion amplifier sensor that monitors the operating characteristics of the amplifier and also from a feedback control circuit that provides frequency correlated input and feedback data. The processed data from the predistortion algorithm engine is then input into the predistortion computation engine along with the carrier signal. An output combiner circuit takes the output of each predistortion computation engine and generates a single correction estimate, which is then input into the nonlinear amplifier for producing a substantially linear output signal.

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Bartlett, IL, United States of America

Robert Stephens