Concatenated RS-Convolutional Codes for Ultrawideband Multiband-OFDM

In this paper, we investigate the performance of concatenated Reed Solomon and convolutional (RS-convolutional) codes for ultrawideband (UWB) multiband orthogonal frequency division multiplexing (MB-OFDM) systems. We show that RS-convolutional codes perform better than single codes at high energy-per-bit to noise ratio (E_b/N₀). We also show that using a bit interleaver between the two concatenated codes degrades the system performance. Our simulations indicate that 10-bit and 11-bit RS-convolutional codes outperform single codes at high E_b/N₀, with gains of more than 4 dB. We further demonstrate that 11-bit RS-convolutional codes outperform turbo codes at high E_b/N₀ by more than 2 dB in various UWB channels