TOA Estimation for Positioning With DVB-T Signals in Outdoor Static Tests

Abstract

Digital television (DTV) signal is a promising signal of opportunity (SoO) for wireless positioning. This paper studies the time of arrival (TOA) estimation on the European standard DVB-T signals in the context of positioning. Theoretical analysis on the autocorrelation of the pilot signal and multipath error envelop (MEE) suggests that DVB-T has the appropriate characteristics for positioning. A software defined radio (SDR) based DVB-T receiver is developed for field testing, in which the radio frequency (RF) DVB-T signals are first sampled by USRP (Universal Software Radio Peripheral), and then algorithms of the coarse symbol synchronization, the pilot detection, the first path acquisition and the delay tracking are sequentially performed to obtain the TOA estimation. To quantify the TOA tracking results on real DVB-T signals, field testing campaigns are carried out in five cities in Southern France. Test results showed that, in the high signal-noise ratio (SNR) condition, the 2-σ error interval is within 1 meter. By taking into account all the field tests, the interval of 95 % accuracy is within 4 m and the corresponding C/N 0 varies from 48 to 62 dB-Hz. In addition, with the developed TOA estimation method, the synchronization of the emitters with GPS (Global Positioning System) time is evaluated and the distance difference of the multiple emitters within single frequency networks (SFNs) are also measured during the tests.

Joint Wireless Positioning and Emitter Identification in DVB-T Single Frequency Networks

“…In our previous work [7], a software defined DVB-T receiver has been developed to estimate the TOA of DVB-T signals for positioning. The results obtained from the field test campaign show that the TOA tracking on real DVB-T signals is capable of achieving good ranging accuracy, with the estimation error within 1 -4 meters depending on the practical signal to noise ratio (SNR).…”

“…, M }. In DVB-T networks, the distance between a DVB-T station and a user can be measured by the TOA estimation [7]. Let d i denote the distance between the user at x x x and the ith DVB-T station at c c c i , which can be expressed as…”

“…In [7], a TOA estimation approach has been proposed, which is capable of tracking weak DVB-T signals for the purpose of ranging, even in the case that the received signals are not strong enough to meet the requirement for the quasi error free (QEF) demodulation. This is because the TOA estimation method in [7] exploits the pilots of DVB-T signals for tracking, which are transmitted with boosted power in comparison to the signals for payload data.…”

“…This is because the TOA estimation method in [7] exploits the pilots of DVB-T signals for tracking, which are transmitted with boosted power in comparison to the signals for payload data. As an example, Fig.…”

“…Furthermore, it is cost effective, due to the reuse of existing DTV facilities [6]. The principles and recent progress in research about the DTV signal assisted navigation and positioning have been overviewed in detail in [7], [8].…”