Advanced Micro Devices Corporation

Chihming (Norman) Chen

Chien-Meen Hwang

Xu Zhou

Howard Hicks

Chih (Rex) Hsueh

Orlando J Canelones

A Viterbi decoder is configured for subtracting each survivor metric for each corresponding encoder state by a prescribed subtraction operator based on a prescribed event. The subtraction of each survivor metric by a prescribed subtraction operator based on a prescribed event minimizes memory requirements in the accumulated metric table by limiting the survivor metric values to a identifiable range. Hence, the Viterbi decoder can be implemented in an economical manner with reduced memory requirements.

Viterbi decoder utilizing compressed survival metrics for reduced memory size requirements

An OFDM receiver configured for measuring frequency error based on comparing prescribed pilot tones from a prescribed group of consecutive symbols in a received OFDM signal. A complex conjugate generator is configured for generating complex conjugates of the prescribed pilot tones of a first subgroup of the consecutive symbols. A multiplier is configured for generating a complex pilot product, for each symbol subgroup position, by multiplying the pilot tones of a second subgroup symbol at the corresponding symbol subgroup position with the respective complex conjugates of the first subgroup symbol at the corresponding symbol subgroup position. A complex summation circuit sums the complex pilot products of the symbol subgroup positions to obtain an accumulated complex value. A error calculator calculates the frequency error from the accumulated complex value for use in correcting frequency offset.

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Cupertino, CA, United States of America

Chihming (Norman) Chen