Space and frequency diversity characterization of mobile GNSS receivers in multipath fading channels

Abstract

Diversity reception of multipath Global Navigation Satellte System (GNSS) signals offers a new insight into carrier phase-based high-precision positioning. The focus of this paper is to demonstrate the fading independence between space and frequency diversity GNSS signals. In harsh urban environments, multipath components arrive to the mobile receiver antenna with different phases and Doppler shifts, therefore giving rise to the discontinuity of code and Doppler observations and large tracking errors. In this paper, an empirical model of fading GNSS signals is constructed, including power fluctuations and spread metrics. Based on this model, real BeiDou Navigation Satellite System (BDS) signals from two GNSS dual-frequency antennas are characterized, at both information and signal level. The block processing algorithm is utilized for signal investigation. Results show that: (1) a high proportion of asynchronous loss-of-lock (around 16%) is experienced by observations of diversity signals; and (2) power fluctuations of fading signals are uncorrelated in frequency separated branches unconditionally, yet for space diversity signals the independency exists in dynamic fading channels only. The results above corroborate the significant potential gain of diversity reception, and could be further implemented in researches of diversity combined GNSS parameter estimation in dense fading conditions.

Optimized Scheme of Antenna Diversity for Radio Wave Coverage in Tunnel Environment

“…However, the deep fading points caused by the tunnel waveguide effect in these works are not suppressed. On the other hand, antenna diversity, which can overcome spatially selective fading and reduce the received power fluctuation in indoor, urban or suburban environments, has been studied by many researchers [17][18][19] . In [20], the effect of polarization diversity on channel capacity in arched tunnels is studied.…”

Evaluation of Development Level and Technical Contribution of Recent Technologies Adopted to Meet the Challenges of 5G Wireless Cellular Networks

“…Recently, considerable improvements in the theoretical capacity of broadcaster-rich channels, such as wireless local area networks (WLAN1), have been achieved with multi-antenna MIMO architectures for transmission and reception [12]. With the introduction of a new dimension, that of space, and the emergence of the field of space-time processing, the contributions are essentially the achievement of a theoretical capacity exceeding the Shannon limit and the improvement of the quality of service by reducing signal fading by exploiting multiple paths [13].…”

“…After discussing the contributions and challenges to be met for the different tech-Symmetry 2021,13, 635 …”

“…After discussing the contributions and challenges to be met for the different techniques of MIMO systems, the next section focuses on the technical contributions of some other new methods used in 5G WCNs.Symmetry 2021,13, 635 …”

Robust extended state estimation for nonlinear complex networks with colored noise

“…However, complex networks are more common for sensor failures, insensitivity, channel limitations, and data loss, which reduce data credibility. [24][25][26][27] Therefore, when designing the state estimator, sufficient attention should be paid to the inadequacy of measurement information. A complex network state estimator for measuring signal loss and time-varying delay is designed, and the estimation effect is simulated.…”