Localization With DTMB Signal Under Complex Urban Environments

Digital multimedia broadcast (DTMB) signal presents a potential opportunity for wireless localization. This paper studies the time of arrival (TOA) estimation based on the DTMB signal for localization. Theoretical analysis of the autocorrelation on the DTMB signal suggested that the DTMB signal has the characteristics for localization. In this paper, we propose software-defineded radio (SDR) receiver based on the DTMB signal for localization. The key innovations of the proposed SDR receiver are as follows: 1) employing a narrow Early-Minus-Late Power Delay Discriminator (nEML) in the delay-locked loop (DLL) to improve the multipath resistance; 2) proposing a multi-state fusion filter to improve the robustness and accuracy of the loop filter; 3) utilizing the carrier-to-noise radio (C/N0) to remove the range observation influenced by heavy non-line of sight (NLOS) environment, thereby reducing the impact of low-quality observations. The static field experiments show that the accuracy of TOA ranging is 1.666m. The motion experiment results show that the root mean square error (RMSE) of the TOA measurements from the DTMB receiver is about 16m, and the RMSE of the DTMB localization is about 17.7m, which shows that the designed receiver can provide relatively reliable localization results when processing DTMB signal in complex urban environments.