Characterization and mitigation of multipath fading on multi-frequency GNSS signals in urban environment
- PDF / 2,745,609 Bytes
- 9 Pages / 595.276 x 790.866 pts Page_size
- 4 Downloads / 173 Views
ORIGINAL PAPER
Characterization and mitigation of multipath fading on multi-frequency GNSS signals in urban environment Rong Yang1 · Xingqun Zhan1
· Jihong Huang1
Received: 22 July 2020 / Revised: 28 September 2020 / Accepted: 1 October 2020 © Shanghai Jiao Tong University 2020
Abstract The global navigation satellite systems (GNSS) receiver is likely to experience performance degradation in the presence of multipath interferences in indoor and urban canyon environments. There will be multiple reflected signals arriving at the receiver antenna from different paths and directions regarding the different locations of the nearby constructions, causing significant fluctuations and distortions on the amplitude and phase of the direct signals. This is the so-called multipath fading effects and usually exhibit with the random features of temporal, spatial, and frequency diversity across the signal bands. To have a better understanding of the multipath fading effects, a live test was conducted near Lujiazui CBD area in Shanghai. The collected data were processed to characterize the signal attenuations and phase fluctuations on multi-frequency GNSS signals via the detrend code delay, carrier phase, and navigation bit errors. The resulting scintillation index on amplitude, code delay, and carrier phase, e.g., S 4 , σϕ and στ can be calculated. Based on these multipath features, the inter-frequency aiding strategy will be utilized for the multipath mitigations in the multi-frequency tracking loop design. The results demonstrate the effectiveness of the multi-frequency tracking algorithm in the urban environment. Keywords Multipath fading · Multi-frequency tracking · Urban environment · Multipath mitigation · Frequency diversity
1 Introduction With the development of the global navigation satellite system (GNSS), the widespread applications of the high precision navigation terminal will become a reality. However, the performance of the GNSS receiver will be severely compromised in challenging environments, such as indoor, urban canyons, boulevard, and tunnels. Multiple reflected signals arrived at the receiver antenna from different paths and directions regarding the different locations of the nearby constructions, causing significant fluctuations and distortions on the amplitude and phase of the direct signals. In some extreme cases, the line-of-signal (LOS) signals will be completely blocked. Only non-line-of-sight (NLOS) reception is available. All these factors, i.e., signal interruption, NLOS,
B
Xingqun Zhan [email protected] Rong Yang [email protected] Jihong Huang [email protected]
1
Shanghai Jiao Tong University, Shanghai, China
and multipath can refer to the so-called multipath fading or shadowing effects and usually exhibit the random features of temporal, spatial, and frequency diversity across the signal bands. More importantly, these effects can introduce code and carrier tracking errors, leading to cycle slips or loss of lock, and in turn degrading GNSS positioning accuracy and robustness. A
Data Loading...
