Delay Estimation for Time Synchronization of a Bistatic Transfer Function Measurement Setup to Single Received Pulses

In this paper, an efficient novel two-staged signal processing approach to synchronize a receiver to single received pulses is presented. Based on delay estimation between the transmitted and received signal the beginning of a single measurement pulse is indicated. In order to measure the transfer function of rural environments a pulse modulated chirp train is transmitted. Because of the bistatic nature of the measurement system a pulse synchronization in the receiver is needed to process each received pulse individually to estimate the transfer function over several pulses and to further improve estimation accuracy. Our approach uses a spectral windowed generalized cross-correlation with a kernel function to get a prewhitened correlation spectrum, leading to sharper cross-correlation peaks in time domain and a more accurate delay estimation in the first stage. Because the prewhitening step and spectral windowing introduce a sinc-like convolution with the time domain signal, sinc-interpolation is performed to estimate the delay. We demonstrate the performance of our approach both in simulation and with real measurement data.