Convergence throughput gain in a unified parallel turbo receiver

Abstract

In pursuit of bringing high end applications on radio platforms, recent and evolving wireless standards impose stringent requirements in the shape of high throughputs, error rate performance close to theoretical limits and multi mode transmissions to efficiently use bandwidth in different channel conditions. In the presence of these requirements, the designer comes across contradicting requirements. In fact, in order to handle error rate performance the iterative (Turbo) processing (Turbo/LDPC decoding, Turbo demodulation and Turbo Equalization) is common implementation practice in baseband receivers. However, this creates bottleneck in achieving imposed throughputs. In this scenario, parallelism study and resulting throughput gains while keeping same error rate convergence, provides the designer concrete results to establish compromise among design constraints. In this paper, first of all three level of parallelism study is presented on turbo decoding, turbo demodulation and MIMO turbo equalization. To aid the designer in taking decision during the design, mathematical expressions for throughput gain in unified parallel turbo receiver are provided. Throughput gain for different system scenarios are computed by using system parameters and simulation results in derived expressions.