Vectorized and federated software receivers combining GLONASS and GPS

Abstract

In traditional federated receiver, all the tracking channels work independently, and there is no interaction among them. However, in vectorized receiver, stronger channels aid others in their tracking. Such architecture makes a receiver to be of interest for positioning in urban canyons and harsh environments. On the other hand, the combination of GPS and GLONASS as the only augmented global constellations is utilized to increase the availability of the receivers which is defined as the percentage of the epochs with enough number of tracked satellites for solving the positioning equation. We report about the software implementation of a GPS-combined-GLONASS Vectorized Receiver (GGVR) and performance assessment of this architecture in signal attenuation and blocking incidents. We also compare the GGVR performance with a GPScombined-GLONASS Federated Receiver (GGFR). Experimental tests in different case studies are included. The results show that in the static blocking situation, the GGVR can reacquire the signal immediately after the momentary outage while the GGFR must return to acquisition stage. For two dynamic case studies, one in a suburban road and one in an urban canyon, the position results on the road are the same, but in an urban environment, the GGFR has only 88% availability in contrast to 100% availability of the GGVR.

Vector-tracking-based GNSS/INS Deep Coupling and Experiment Platform for Urban Scenarios

“…Hsu evaluated the performance of the vector delay-locked loop (VDLL) with multipath and NLOS reception, and the results of positioning and code discriminator were presented [11]. A GPS/GLONASS vector tracking receiver was designed and tested in an unknown multipath environment in [12]. But there are few literatures reported on the deep coupling system for multipath signals.…”

Toward Autonomous Driving in Arctic Areas

“…However, various error sources affect the accuracy and reliability of the position solutions computed using the GNSS signals and especially in urban canyons GNSS is significantly degraded or unavailable. For overcoming the aforementioned navigation challenges, research has been very active for decades for developing novel improved signal processing techniques [75], [27] and finding a suitable set of other methods for augmenting or replacing the use of GNSS. The size, price and power consumption requirements set for the system complicate the method development further, and therefore the set of equipment, error modelling and algorithms used for integrating measurements from different sources, has to be considered carefully.…”

Increasing the Resistance of GPS Receivers by Using a Fuzzy Smart Estimator in Weak Signal Conditions

“…In these methods, position and velocity information from INS can therefore be used to aid the tracking loops for removing dynamic stress from the GPS signal. Other work based on vector tracking has been done to combine tracking channels without the use of an auxiliary system such as INS (Lashley et al, 2009; Brewer and Raquet, 2016; Tabatabaei et al, 2017). In these methods, EKF is used to correct Doppler frequency shift and code delay errors.…”