Design of Fixed-Point Processing Based Turbo Codes Using Extrinsic Information Transfer Charts

—The operand-width specifications in fixed-point hardware implementations of turbo code decoders is an important design issue, since this governs the trade-off between the decoder’s performance and its complexity, cost, area and energy consumption. The investigation of this issue would be extremely time-consuming in the conventional approach, which relies upon Monte-Carlo simulation based Bit Error Ratio (BER) analysis. In this paper, we propose a generic design method, which uses EXtrinsic Information Transfer (EXIT) chart analysis to simplify this design process. Our method is not only an order of magnitude faster than the conventional Monte-Carlo simulation based approach, but also offers deeper insights into why performance degradations are imposed by insufficient operandwidth specifications. The benefits of our generic method are demonstrated in the context of a turbo decoder, allowing accurate specifications to be obtained and compared to those suggested by previous wor...

• Type: Journal
• Year: 2010
• Where: VTC
• Authors: Liang Li, Robert G. Maunder, Bashir M. Al-Hashimi, Lajos Hanzo
• Keywords: Communications, Conventional Monte-carlo Simulation, Monte-carlo Simulation, Turbo Code Decoders, VTC 2010