NRPos: A Multi-RACH Framework for 5G NR Positioning

Zhou

IEEE Internet Things J.

et al. 2022

Indoor positioning is one of the core technologies of Internet of Things (IoT) and artificial intelligence (AI), and is expected to play a significant role in the upcoming era of AI. However, affected by the complexity of indoor environments, it is still highly challenging to achieve continuous and reliable indoor positioning. Currently, 5G cellular networks are being deployed worldwide, the new technologies of which have brought the approaches for improving the performance of wireless indoor positioning. In this paper, we investigate the indoor positioning under the 5G new radio (NR), which has been standardized and being commercially operated in massive markets. Specifically, a solution is proposed and a software defined receiver (SDR) is developed for indoor positioning. With our SDR indoor positioning system, the 5G NR signals are firstly sampled by universal software radio peripheral (USRP), and then, coarse synchronization is achieved via detecting the start of the synchronization signal block (SSB). Then, with the assistance of the pilots transmitted on the physical broadcasting channel (PBCH), multipath acquisition and delay tracking are sequentially carried out to estimate the time of arrival (ToA) of received signals. Furthermore, to improve the ToA ranging accuracy, the carrier phase of the first arrived path is estimated. Finally, to quantify the accuracy of our ToA estimation method, indoor field tests are carried out in an office environment, where a 5G NR base station (known as gNB) is installed for commercial use. Our test results show that, in the static test scenarios, the ToA accuracy measured by the 1-σ error interval is about 0.5 m, while in the pedestrian mobile environment, the probability of range accuracy within 0.8 m is 95%.Index Terms-5G new radio (NR), indoor positioning, Internet of Things (IoT), software defined radio (SDR), time of arrival (ToA), delay locked loop (DLL), carrier phase, ranging estimation.

Section: Performance Analysis Of Toa Estimationmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Carrier Phase Ranging for Indoor Positioning With 5G NR Signals

Zhou

IEEE Internet Things J.

et al. 2022

IEEE J. Select. Areas Commun.

“…Meanwhile, the positioning signals used in current researches are PRS-like 1 , which must be broadcasted in a small amount of time slots to avoid occupying too many communication resources [24], [25]. This not only limits its ranging accuracy as the intermittent signal is hardly tracked, but also leads to low measuring frequency because of the long interval between two positioning frames, which cannot meet the accuracy and real-time requirements of fast train positioning [10], [26]. Although higher positioning accuracy could be achieved by placing two LCXs perpendicular to each other [27], it cannot be implemented in tunnels.…”

Section: Introductionmentioning

confidence: 99%

New Signal and Algorithms for 5G/6G High Precision Train Positioning in Tunnel With Leaky Coaxial Cable

Yin,

Song,

et al. 2024

High precision train positioning is a crucial component of intelligent transportation systems. Tunnels are commonly encountered in subways and mountainous regions. As part of the communication system infrastructure, Leaky CoaXial (LCX) Cable is widely equipped as antenna in tunnels with many advantages. LCX positioning holds great promise as a technology for rail applications in the upcoming B5G (beyond-5G) and 6G eras. This paper focuses on the LCX positioning methodology and proposes two novel algorithms along with a novel communicationpositioning integration signal. Firstly, a novel algorithm called Multiple Slot Distinction (MSD) LCX positioning algorithm is proposed. The algorithm utilizes a generated pseudo spectrum to fully utilize the coupled signals radiated from different slots of LCX. This approach offers higher time resolution compared to traditional methods. To further improve the positioning accuracy to centimeter-level and increase the measuring frequency for fast trains, a novel communication-positioning integration signal is designed. It consists of traditional Positioning Reference Signal (PRS) and a significantly low power Fine Ranging Signal (FRS). FRS is configured to be continuous and superposed onto the cellular signal using Non-Orthogonal Multiple Access (NOMA) principle to minimize its interference to communication. A twostage LCX positioning method is then executed: At the first stage, the closest slot between the receiver and LCX is estimated by the proposed MSD algorithm using PRS; At the second stage, centimeter-level positioning is achieved by tracking the carrier phase of the continuous FRS. This process is assisted by the closest slot estimation, which helps mitigate interference between neighboring slots and eliminate the integer ambiguities. Simulation results show our proposed LCX position methodology outperforms the existing ones and offer great potentials for future implementations.

IEEE J. Select. Areas Commun.

“…While communication performance will degrade significantly without these resource blocks. Even so, PRS can not meet the accuracy and latency requirements simultaneously [11]. It is because the discontinuous PRS is hardly tracked which leads to low ranging accuracy, and there is a long interval between two PRS frames which leads to low measuring frequency [12].…”

Section: Introductionmentioning

confidence: 99%

“…On the other hand, to obtain higher measuring accuracy, positioning components should be transmitted continuously from different base stations (BS). Then, severe near-far effect between these positioning components make the signals from far BSs more difficult to be accessed [11], [13]. Consequently, poor geometric distribution of BSs is achieved which further worsens the positioning accuracy and reliability [14].…”

Section: Introductionmentioning

confidence: 99%

Design and Performance Analysis of Multi-Scale NOMA for Future Communication-Positioning Integration System

Yin

Cao

et al. 2022

This paper presents a feasibility study of a novel multiple access technique called Multi-Scale Non-Orthogonal Multiple Access (MS-NOMA) for the next generation communication-positioning integration system. Different from the traditional positioning signals which are mostly Time Division Multiple Access with communication signals and are broadcast to all users, MS-NOMA supports continuous positioning waveform and flexible configurations for different positioning users to obtain higher ranging accuracy, lower positioning latency, less resource consumption and better signal coverage. Our major contributions are: Firstly, we present the MS-NOMA waveform and evaluate its performances by theoretical and simulation analyses. The results show it is feasible to use the MS-NOMA waveform to achieve high positioning accuracy and low Bit Error Rate with little resource consumption simultaneously. Secondly, to achieve optimal positioning accuracy and signal coverage, we model the power allocation problem for MS-NOMA as a convex optimization problem satisfying the Quality of Services requirement and other constraints. Then, we propose a novel Communication and Positioning Performances constrained Positioning Power Allocation (CP4A) algorithm which allocates the power of all P-Users iteratively. The theoretical and numerical results show our proposed MS-NOMA waveform with CP4A algorithm has great improvements of ranging/positioning accuracy than traditional Positioning Reference Signal in cellular network.