Design of a parallelized direct position estimation‐based GNSS receiver

Abstract

Theoretical results conclude that Direct Position Estimation (DPE)‐based Global Navigation Satellite System (GNSS) receivers can achieve more robust localization than their conventional two‐step counterparts. However, compared to conventional approaches, there is a much smaller body of work for DPE, and DPE receiver implementations are highly experimental. This work surveys DPE techniques from the literature and presents a software‐defined parallelized DPE‐based receiver prototype built on popular DPE techniques. The parallelized receiver software, along with a companion sequential implementation, is made available to the community as an open source. The GPU usage of the parallelized DPE‐based receiver is profiled and compared to the companion sequential implementation and another sequential implementation presented in the literature. Through the literature survey, discussion of the open‐source receiver software, and the performance evaluation of the receiver, resultant insights for design decisions are presented.

An Absolute-Position-Aided Code Discriminator Towards GNSS Receivers for Multipath Mitigation

“…Then, the proposed APA VDFLL can properly estimate the remained code phase error in the discriminating process, as the expectation of the discriminating errors approaches the ones of the biased errors more than the results produced by the standard VDFLL. Similarly, the unexpected remained multipath error is further estimated by (5) in this work and removed from the proposed APA code phase discriminator ( 2) by ( 4).…”

“…In summary, the code frequency estimation is improved with (3) aided by the APA VDFLL discriminator. Furthermore, the multipath delay error is able to be mitigated in the proposed algorithm with (5). It is also worth noting that once the absolute position estimation as well as the other error source models are accurate enough, the multipath error can be almost eliminated based on (4).…”

“…The test spot and the sky plot are shown in Figure 4. The satellite of PRN 21 is selected as the master satellite to estimate the multipath error proposed by (5).…”

“…Direct position estimation (DPE) takes advantages of the spatial information of the GNSS satellites by optimizing the discriminating error with the user's 3D position and it has been proved to be superior to the traditional algorithms for the multipath mitigation [4]. It attracts lots of attentions of the researchers in recent times for its state-of-the-art concept applied to the GNSS receiver design [5]. Vector tracking algorithms are also very popular to deal with the interfered signals in the receiver design [6] and it has been recently proved to be efficiently classify the LOS and NLOS signals [7].…”