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A linear quadratic optimization based TOA estimation scheme for IR-UWB systems

This paper proposes an energy detection based time of arrival (TOA) estimation scheme for impulse radio ultra-wideband (IR-UWB) systems. The proposed scheme is composed of two stages in performing the TOA estimation: initial signal acquisition (ISA) and fine timing estimation (FTE). In the ISA stage, a linear quadrature optimization based weighting scheme is proposed to coarsely capture the arrival of the IR-UWB signals. Capitalizing on the acquisition of the IR-UWB signal in a relatively wide time range, this paper develops in the FTE stage a double-threshold based search back method tailored for locating the leading edge of the IR-UWB signal. Simulation results illustrate that the linear quadrature optimization based algorithm can effectively seize the arrival of the UWB signals and the double-threshold strategy significantly improves the TOA estimation accuracy in terms of mean absolute error (MAE) performance.