A DSP-Based Implementation of Low Complexity Turbo Equalization

Turbo equalizer exhibits dramatic performance improvement comparing with conventional equalizers by combining equalization and decoding, where soft information is iteratively exchanged between the equalizer and decoder. However, turbo equalization is much more complex and hence precludes practical implementation when considering multilevel modulations over highly dispersive channels. In this letter, we present the implementation of low complexity turbo-equalization based on soft feedback interference cancellation (SFIC) on Texas Instruments TMS320C6416 device. The SFIC offers a very low computational complexity depending only linearly on the channel memory length. With appropriate data quantization, the performance loss is negligible comparing with floating-point turbo equalizer.

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