Telefonaktiebolaget Lm Ericsson (publ)

Wensheng Huang

Raymond L Toy

Peter Malm

Zhiyong Yan

Bogdan Sutkowski

In receiving a radio block comprising a plurality of bursts, burst data is saved prior to demodulating each burst using an independent preliminary modulation technique decision. When a global modulation technique decision over the radio burst is formulated, if the preliminary modulation technique decision for one or more bursts disagrees, data associated with that burst may be retrieved and demodulated using the global modulation technique decision. In one embodiment, the mismatching burst is erased and decoding over the block is attempted, with the second demodulation being performed only if a decoding metric indicates decode errors. In another embodiment, each mismatching block is re-demodulated as soon as a global modulation technique decision is formulated and a mismatch to the preliminary modulation technique decision is detected. In both embodiments, an increase in the number of soft bits improves decoder performance.

Blind modulation detection

Synchronization between a transmitter and a receiver with respect to the boundary of higher-layer logical data structures is improved by considering both the statistical likelihood of the value of a transmitted boundary indicator and the quality of the channel during the transmission. A boundary indicator received under poor channel quality, that is decoded to a statistically unlikely value, is suspect and one or more retransmission is requested. A reliable value of the boundary indicator is a retransmitted boundary indicator received during good channel conditions; the value of two boundary indicators received successively, both under poor channel conditions, that decode to the same value; or a majority vote of three successive boundary indicators, the first two received under poor channel conditions. The accuracy of the received boundary indicator is increased, at a cost of one, or at most, two, retransmissions.

Data structure boundary synchronization between a transmitter and receiver

The present invention comprises an interleaver that uses a reduced interleaving table to generate interleaved output data blocks from input data blocks. By iteratively applying the reduced interleaving table to bits in the input data blocks, the interleaver generates output data blocks equivalent to those that would have been generated using a full-size interleaving table. According to one embodiment of the present invention, the interleaving circuit includes a grouping circuit, a permuting circuit, and a mapping circuit. The grouping circuit groups the bits of each data block into a plurality of sub-blocks, while the permuting circuit independently permutes the data bits in each sub-block using the reduced interleaving table to generate permuted sub-blocks. The mapping circuit maps the bits from each permuted sub-block to one or more output data blocks, where the bits in each output data block may comprise bits from different sub-blocks and/or different input data blocks.

Intelligent table-driven interleaving

In a packet-based data transmission including incremental redundancy (IR) protocols, the memory consumption of the IR protocol is reduced by compressing and storing failed data units in their punctured format. The failed data units are compressed using low complexity compression/decompression algorithms. The compression algorithm includes two parts: calculating and storing a scale factor for each transmission burst that estimates the soft values in the burst, and storing each soft values' sign in local memory instead of the complete soft value. If the currently received data unit is a retransmission, its compressed versions in the punctured format stored in the IR memory are decompressed, de-punctured and combined with the currently received data unit. The combined data unit is then decoded. The decompression restores an estimated soft-value by multiplying the sign value stored in the IR memory with its corresponding scale factor obtained from a mapping table.

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Cary, NC, United States of America

Wensheng Huang