Code aided near full rate multiuser TR-UWB systems

A mean estimator has been proposed to improve template for the correlation receiver employed in a single user transmitted reference (TR) ultra wideband (UWB) system. The receiver yields satisfactory detection performance even in the presence of inter-pulse interference (IPI) while transmission rate is increased to near full rate compared to a 50% rate loss in a conventional TR system. This paper further extends the TR modulation to a multiuser scenario by assigning a pair of frame rate pseudo-random (PN) sequences to each user, modulating the amplitude of each pulse in the doublet respectively, irrespective of adopted data modulation formats. Given a user's PN sequence that modulates the reference pulse, the mean estimator is still applicable to estimate channel-distorted waveform for that user in the presence of IPI and multiple access interference. Then correlation based data demodulation is assisted by the other PN sequence modulating the data pulse, and constructed template from estimated waveform. Waveform estimation error and bit error rate detection performance are studied analytically and experimentally.

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