Super-orthogonal convolutional coding with orthogonal pulse waveform for ultra wideband communications

Ultra-wideband (UWB) technology is expected to serve as a core physical layer technology of the wireless personal area network (WPAN) for indoor high data rate communications. In a conventional UWB system, a transmitter sends a large number of pulses repeatedly for each data symbol to gain SNR because of the stringent limitation of the transmit power. This can be considered as a simple repetition block code, which generally has a limited coding gain. We propose a new UWB system employing super-orthogonal convolutional coding in conjunction with a set of orthogonal waveforms based on Hermite polynomial functions. Combination of the super-orthogonal convolutional code and orthogonal waveforms can effect high data rate communication with good error performance. Performance analysis shows that the proposed scheme performs significantly better than the uncoded system in a multiuser and multipath environment.