Atheros Communications, Inc.

Lars E Thon

William John McFarland

Paul J Husted

Jeffrey M Gilbert

Ardavan Maleki Tehrani

Yi-Hsiu Wang

John S Thomson

Tao Fei Samuel Ng

David Kuochieh Su

Masoud Zargari

Paul J Hustad

A Viterbi decoding system interprets bits in received QAM constellations as many-valued parameters rather than binary valued parameters. It performs the Viterbi algorithm using these many-valued parameters to provide results superior to hard decision decoding. Rather than applying a hard 0-1 function to the QAM data, the system uses a non-stepped linear or curved transfer function to assign values to the bits. In another aspect, a system differentiates between data bits based on their estimated reliability, giving more emphasis to decoding reliable bits than unreliable bits using any of a variety of techniques. By differentiating between good and bad bits and de-emphasizing or ignoring unreliable bits, the system can provide a significant reduction in uncorrectable errors and packet loss.

Decoding system and method for digital communications

A Viterbi decoding system interprets bits in received QAM constellations as many-valued parameters rather than binary valued parameters. It performs the Viterbi algorithm using these many-valued parameters to provide results superior to hard decision decoding. Rather than applying a hard 0-1 function to the QAM data, the system uses a non-stepped linear or curved transfer function to assign values to the bits. In another aspect, a system differentiates between data bits based on their estimated reliability, giving more emphasis to decoding reliable bits than unreliable bits using any of a variety of techniques. By differentiating between god and bad bits and de-emphasizing or ignoring unreliable bits, the system can provide a significant reduction in uncorrectable errors and packet loss.

An embodiment of the present invention provides an automatic gain control system for a wireless receiver that quickly differentiates desired in-band signals from high power out-of-band signals that overlap into the target band. The system measures power before and after passing a received signal through a pair of finite impulse response filters that largely restrict the signal's power to that which is in-band. By comparing the in-band energy of the received signal after filtering to the total signal energy prior to filtering, it is possible to determine whether a new in-band signal has arrived. The presence of this new in-band signal is then verified by a multi-threshold comparison of the normalized self-correlation to verify the presence of a new, desired in-band signal.

Self-correlation detection in automatic gain calibration

In-band and out-of-band signal detection for automatic gain calibration systems

A control interface, which includes both master and slave devices, can provide buffering of input data packets, thereby allowing configurations of the integrated circuit to be modified quickly and efficiently. Additionally, the control interface can be sized and configured to receive digital signals from any number of nodes on an integrated circuit, thereby facilitating the testing, lab characterization, and debugging of those nodes. Finally, the control interface can advatageously control the monitoring of analog components on the integrated circuit, thereby significantly reducing the number of pins for such monitoring. The control interface has particular relevance to highly integrated circuits that utilize analog and/or mixed signals.

Flexible control interface for integrated circuit

Growing community of inventors

San Jose, CA, United States of America

Lars E Thon