National Semiconductor Corporation

Cadence Design Systems, Inc.

Radiant Networks Plc

Manouchehr S Rafie

Tushar Ramanlal Shah

Jun Lu

Lin Yang

Yan Zhong

Syang-Myau Hwang

Dengwei Fu

An architecture for a wideband code-division multiple access (WCDMA) baseband system is provided. The system comprises separate processing blocks (e.g. cell search, RAKE receiver, transmitter engine, and error correction). Each block comprises a hard-wired logic block and a CSP (communication signal processor). The architecture of each CSP is optimized to perform a particular signal processing function. Each CSP has an associated memory architecture that is optimized for the particular signal processing function. Each memory architecture includes at least two memories that are independently addressable to support simultaneous read and/or write access. The instruction set for each CSP is optimized based on the particular signal processing function. Each instruction set includes instruction words that are optimized for the particular signal processing function. One or more instruction words support simultaneous read/write accesses in parallel.

Communication signal processor architecture

A SWP- (Sub-Word Parallelism-) based RAKE receiver for a Wideband Code-Division Multiple Access (WCDMA) mobile station is optimized to perform channel de-rotation and data combining. The RAKE receiver comprises SIMD (Single Instruction, Multiple Data) instructions, which can perform a complex multiplication for a channel de-rotation in a single cycle. The SIMD instructions can also perform a complex addition for data combining in a single cycle. Optimization of the RAKE receiver reduces power consumption and costs, enhances performance, and provides extensibility for next-generation architectures.

Processor-implemented RAKE receiver

A method for a carrier phase recovery apparatus in a multiple-link hopping radio system includes hopping among a plurality of radio links to receive bursts of radio signals on the plurality of radio links and determining channel information for each radio link from a received burst on the radio link. Further, the method includes storing the determined channel information and using the determined channel information for the radio link to reliably recover the carrier phase of a next received burst on the radio link.

Carrier phase recovery system for adaptive burst modems and link hopping radio networks

A method for an adaptive equalization apparatus in a multiple-link hopping radio system includes hopping among a plurality of radio links to receive variable-length bursts of radio signals on the plurality of radio links and equalizing amplitude and phase variations of a slow channel for each radio link from a received burst on the radio link. Further, the method includes storing the estimated tap coefficients pertinent to each radio link and using the tap weights of the current burst of the radio link to reliably pre-compensate the channel amplitude and phase distortion of a next received burst on the radio link.

Adaptive equalizer system for short burst modems and link hopping radio networks

Described is an one bit matched filter for generating a sequences of correlations between a signal bit stream and a sample stream of n sample bits. The n sample bits are arranged in a rang of n bit positions n, n-1, . . . , 2, 1. Among the n sample bits, m boundary positions are defined based on the bit pattern of the sample stream, where m&lt;n. At a specific time T(k), the m boundary positions are used to generate a Contribution (k) for a section of signal bits that are shifted into the n bit positions. At the time T(k), a Correlation (k) is generated by adding the Contribution (k) with the Correlation (k-1) that was generated at the previous time T(k-1).

One bit matched filter with low complexity and high speed

A Viterbi decoder generates a branch metric table from first and second data signals taken at two sample times and provides selected branch metrics to an add/compare/select circuit in response to branch indices from a branch index generator. The branch metrics in the branch metric table are the sixteen combinations of the sum of the first and second parallel data signals at first and second sample times and the inverse of such signals. The branch index generator generates the branch indices in response to a received state from the add/compare/select circuit, convolutional code polynomials and the possible states of a radix-4 trellis. The add/compare/select generates a survivor path decision based on the selected branch metrics.

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Sunnyvale, CA, United States of America

Manouchehr S Rafie