Delay estimation for DVB-T signals in adverse multipath scenarios

Abstract

Timing approaches, such as time of arrival (TOA) and time difference of arrival (TDOA), employed with DVB-T are sensitive to the presence of multipath errors. This paper studies the delay estimation in adverse multipath scenarios using the DVB-T signals. A data-directed delay tracking mechanism is presented for signal tracking to estimate the time delay. Three different delay locked loops (DLLs) are considered to mitigate the multipath errors, i.e. the early minus late (EML), the narrow EML (nEML) and the High Resolution Correlator (HRC). Simulation results are compared for tracking the DVB-T signals in the suggested Rice and Rayleigh channels. Simulation results show that the correlation outputs of the DVB-T signals are relatively smooth, which cause the DLLs difficulty to detect the closely spaced multipaths. For tracking the first peak of the correlation, HRC and nEML are better than EML.