SBIR-STTR Award

LinCom proposes the design of a codec (encoder-decoder) VLSI product using the Turbo codes which will overcome the latency and BER floors which have been associated with these codes. We are proposing a new innovative technique which will hopefully provide performance comparable to Turbo codes but without the delay and complexity penalties. The resulting product would provide BER's below 10-9 with modest latency and complexity and high coding gain. The Phase I effort will consist of: a) performing a trade study of possible codes designs; b) select a limited number of candidate designs based on BER performance, data throughput, and latency; and c) select the candidate design which is most suitable for implementation in VLSI hardware. Some of the areas to be investigated include the Turbo Interleaver size and type, the types of CC's and their code rates, serial vs parallel concatenation, puncturing method, and the structure of the interleavers. Also to be investigated will be the complexity of the implementation, the required computational speed, and gate count. Anticipated Benefits/

Potential Commercial Applications:
The proposed product provides increased coding gain over conventional coders and allows for greater data rates or lower power/smaller equipment. The Turbo codes product described here could be used for ATM data links, Digital TV, TCP-IP links, digital satellite links, and all digital modem applications requiring high coding gains. The product would be especially suited for data links requiring BER under 10-9 and modest delays.

LinCom proposes the design of a codec (encoder-decoder) product using the Turbo codes which will overcome the latency and BER floors which have been associated with these codes. We are proposing a new innovative technique which will provide performance comparable to Turbo codes but without the delay and complexity penalties. The resulting product would provide BER's below 10-9 with modest latency and complexity and high coding gain. In the Phase I effort, LinCom demonstrated that its proposed innovative codec architecture could provide comparable or better performance to a standard turbo codec with implementation complexity reduced by greater than an order of magnitude. Optimization is continuing, and LinCom expects to reduce the complexity even further. In the Phase II effort, LinCom will build a prototype of its innovative codec architecture. The design will be implemented using a high level, behavioral description language (VHDL) to model and simulate system performance. The VHDL netlist will then be partitioned and compiled into field programmable gate arrays. The prototype will serve as a demonstration platform for potential customers of LinCom's innovative codec.

Benefits:
The proposed product provides increased coding gain over conventional codecs and allows for greater data rates or lower power/smaller equipment. The Turbo codec product described here could be used for ATM data links, Digital TV, TCP-IP links, digital satellite links, and all digital modem applications requiring high coding gains. The product would be especially suited for data links requiring BER under 10-9 and modest delays.