Multiple Faulty GNSS Measurement Exclusion Based on Consistency Check in Urban Canyons

Abstract

Abstract-Sensors play important roles for autonomous driving.Localization is definitely a key one. Undoubtedly, global positioning system (GPS) sensor will provide absolute localization for almost all the future land vehicles. In terms of driverless car, 1.5 meters of positioning accuracy is the minimum requirement since the vehicle has to keep in a driving lane that usually wider than 3 meters. However, the skyscrapers in highly-urbanized cities such as Tokyo and Hong Kong, dramatically deteriorate GPS localization performance, leading more than 50 meters of error. GPS signals are reflected at modern glassy buildings which caused the notorious multipath effect. Fortunately, the number of navigation satellite is rapidly increasing in a global scale since the rise of multi-GNSS (global navigation satellite system). It provides an excellent opportunity for positioning algorithm developer of GPS sensor. More satellites in the sky implies more measurements to be received. Novelty, this paper proposes to take advantage of the fact that clean measurements (refers to line-of-sight measurement) are consistent and multipath measurements are inconsistent. Based on this consistency check, the faulty measurements can be detected and excluded to obtain better localization accuracy. Experimental results indicate that the proposed method can achieve less than 1 meter lateral positioning error in middle urban canyons.

Performance assessment of 3D‐mapping–aided GNSS part 1: Algorithms, user equipment, and review

“…This is based on the principle that measurements from “clean” direct LOS signals produce a more consistent navigation solution (ie, with smaller residuals) than those from NLOS and severely multipath‐contaminated signals. In dense urban areas, a subset comparison approach is more robust than conventional sequential testing . When a filtered navigation solution is implemented, measurement innovation‐based outlier detection can also be used.…”

“…In dense urban areas, a subset comparison approach is more robust than conventional sequential testing. 14,15 When a filtered navigation solution is implemented, measurement innovation-based outlier detection can also be used. Furthermore, by comparing a series of innovations, NLOS reception, characterized by a bias, may be distinguished from multipath interference, characterized by a larger than normal variance.…”

BeiDou System (BDS) Triple-Frequency Ambiguity Resolution without Code Measurements

“…Because the code multipath on each satellite is dependent on the instantaneous geometric relation between the satellite, the receiver antenna, and the surrounding environment, it is very difficult (if not impossible) to handle rigorously by utilizing the commonly used code noise-weighting strategies, such as the elevation-dependent weighting function, the variance and covariance components estimation [40], and the related ray-tracing techniques [41,42]. In contrast, the proposed BDS phase-only method At threshold U = 2, the TTFF value for the phase-code method is 466 s; while it is only 2 s for the phase-only method.…”

“…Success percentage = Number of successful test sessions Number of total test sessions × 100 (%) (41) where a successful test session has to achieve the TTFF. Figure 7 displays the success percentages over the 37 km and 256 km baselines with commonly used ratio test thresholds (U = 2, 2.5, 3) [20,26].…”

Intelligent Viaduct Recognition and Driving Altitude Determination Using GPS Data

“…Second, the pseudorange measurements can be evaluated using the idea of a consistency check. As indicated by [41], the pseudorange residue can be regarded as an evaluation index of the consistency between all the measurements.…”