Indoor Positioning of Low-Cost Narrowband IoT Nodes: Evaluation of a TDoA Approach in a Retail Environment

Abstract

The localization of iot nodes in indoor scenarios with strong multipath channel components is challenging. All methods using radio signals, such as rss or aoa, are inherently prone to multipath fading. Especially for tof measurements, the low available transmit bandwidth of the used transceiver hardware is problematic. In our previous work on this topic we showed that wideband signal generation on narrowband low-power transceiver chips is feasible without any changes to existing hardware. Together with a fixed wideband receiving anchor infrastructure, this facilitates tdoa and aoa measurements and allows for localization of the fully asynchronously transmitting nodes. In this paper, we present a measurement campaign using a receiver infrastructure based on sdr platforms. This proves the actual usability of the proposed method within the limitations of the bandwidth available in the ism band at 2.4GHz. We use the results to analyze the effects of possible anchor placement schemes and scenario geometries. We further demonstrate how this node-to-infrastructure-based localization scheme can be supported by additional node-to-node rss measurements using a simple clustering approach. In the considered scenario, an overall positioning rmse of 2.19m is achieved.

Research and Implementation of Indoor 3D Positioning Algorithm Based on LED Visible Light Communication and Corresponding Parameter Estimation

“…Compared to TOA and TDOA, the RSS and AOA methods achieve localization without full synchronization of time. Compared with RSS, TOA, and TDOA, AOA requires fewer reference points, but it requires relatively more hardware conditions and higher positioning costs [ 34 ]. Please refer to Table 4 .…”

A Reconfigurable Full-Digital Architecture for Angle of Arrival Estimation

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Advances in Indoor Positioning and Indoor Navigation

“…Neunteufel et al [ 11 ] deal with the problem of multipath faces for radio signals, which affect methods based on received signal strength (RSS), angle of arrival (AoA), or time of flight (ToF) measurements. In this work, they present a measurement campaign using a receiver infrastructure based on software-defined radio (SDR) platforms.…”