HSGPS Signal Analysis and Performance under Various Indoor Conditions

Abstract

High‐sensitivity GPS (HSGPS) receivers permit GPS signal measurements to be acquired and tracked in certain indoor environments where this previously was not possible. However, solution reliability and accuracy are significantly degraded because of the nonavailability of some satellites, multipath errors, measurement noise associated with the low power of the remaining signals, and echo‐only and cross‐correlation signal tracking. The focus of this paper is on improving static‐mode HSGPS positioning performance in terms of accuracy and reliability. Thus, various techniques, such as height fixing, simulation‐based noise modeling, reliability testing in terms of fault detection and exclusion (FDE), and batch processing, are implemented. An XTrac‐LPTM HSGPS evaluation kit, developed by SiRF Technologies Inc., is used to investigate some indoor environments by analyzing the fading and pseudorange error conditions. In addition, the measurements provided by the receiver are used to test the performance of the algorithms intended to improve the HSGPS positioning capability.

Position and velocity reliability testing in degraded GPS signal environments

“…6 over a period of ca. 12 h (Lachapelle et al 2003). During the test, the wooden garage door was closed.…”

Sensing and Classifying Impairments of GPS Reception on Mobile Devices

“…For investigations of GPS positioning in urban and indoor environments and its limitations, see, e.g., [8,22,27]. High-Sensitivity GPS (HSGPS) [12] subsumes advances in GPS receiver technology to alleviate the limitations mentioned above. HSGPS is claimed to allow tracking for received GPS signal strengths down to -190 dBW, corresponding to a nominal SNR value of 14 dB: three orders of magnitude less than the GPS signal strength to be expected in open-sky conditions [16].…”

An MCMC algorithm for BOC and AltBOC signaling acquisition in multipath environments

“…The signal components arriving from indirect paths (which are delayed and attenuated versions of the original signal) and the direct LOS path (if it exists), combine and produce a distorted version of the transmitted signal. The combination may cause constructive and/or destructive interference effects [11]. Many studies aim at characterizing the different kinds of GPS channels, especially the indoor [7], [14] and the urban [15], [20] channels.…”