High accuracy terrestrial radio positioning systems, as a complement to a global navigation satellite system (GNSS), are attracting significant attention from academia and industry. This article investigates the feasibility of positioning based on carrier phase measurements of orthogonal frequency division multiplexing (OFDM) signals. Generally, the carrier phase cannot be obtained from a baseband central carrier (i.e., direct current (DC) subcarrier) of OFDM signals, so we derived the carrier phase by calculating the average phase from two symmetrically located pilot sub-carriers. The sampling clock error and the timing synchronization error, which often occur in practice, can be cancelled by measuring the phase difference between two symmetrically located sub-carriers. The presented approach is simulated for a positioning system based on IEEE 802.11p Wireless LAN. Due to the presence of an initial carrier phase offset, the integer carrier phase ambiguity can, as expected, not be properly resolved. Although we can only obtain a 'float' solution from the observation model, the position accuracy can still achieve decimetre level.
|Title of host publication||Conference proceedings of the NaviTec 2018, the 2018 9th ESA Workshop on Satellite Navigation Technologies and European Workshop on GNSS Signals and Signal Processing (NAVITEC)|
|Number of pages||9|
|Publication status||Published - 2018|
|Event||NaviTec-2018 conference - Noordwijk, Netherlands|
Duration: 5 Dec 2018 → 7 Dec 2018
Conference number: 9
|Period||5/12/18 → 7/12/18|