On the effect of SNR and superdirective beamforming in speaker diarisation in meetings

This paper examines the effect of sensor performance on speaker diarisation in meetings and investigates the use of more advanced beamforming techniques, beyond the typically employed delay-sum beamformer, for mitigating the effects of poorer sensor performance. We present superdirective beamforming and investigate how different time difference of arrival (TDOA) smoothing and beamforming techniques influence the performance of state-of-the-art diarisation systems. We produced and transcribed a new corpus of meetings recorded in the instrumented meeting room using a high SNR analogue and a newly developed low SNR digital MEMS microphone array (DMMA.2). This research demonstrates that TDOA smoothing has a significant effect on the diarisation error rate and that simple noise reduction and beamforming schemes suffice to overcome audio signal degradation due to the lower SNR of modern MEMS microphones. Index Terms — Speaker diarisation in meetings, digital MEMS microphone array, time difference of arrival (TDOA), superdirective beamforming 1

TDoA-based outdoor positioning in a public LoRa network

The performance of LoRa Geo-location for outdoor tracking purposes has been evaluated on a public LoRaWAN network. Time Difference of Arrival (TDOA) localization accuracy, probability and update frequency were evaluated for different trajectories (walking, cycling, driving) and LoRa spreading factors. A median accuracy of 200m was obtained and in 90% of the cases the error was less then 480m

Smart Passive Localization Using Time Difference of Arrival

A smart passive localization system using time difference of arrival (TDoA) measurements is designed and analyzed with the goal of providing the position information for the construction of frequency allocation maps

Lightning Location and Mapping System Using Time Difference of Arrival (TDoA) Technique

Lightning strike is a dangerous natural phenomenon that can cause various problems. Telecommunication subscriber lines (TSLs) and electrical power lines are two systems that are almost always affected by nearby lightning strikes. Voltages in the telecommunication subscriber line (TSL) do get induced by nearby lightning strikes. The induced voltage can be carefully measured and lightning parameters such as the lightning current wave shape, lightning peak current and strike locations be reproduced. Better designs of lightning protection systems can be realised if data on lightning strike distribution in a given region is known. Commercial lightning mapping or locating systems are based on several technologies (Araujo, 2001; Kenneth, 2003). The two most popular methods are those based on the Time of Arrival (ToA) and the Directional Finder (DF) principles. An example of the lightning locating system (LLS) based on the ToA method is the country- wide LLS owned by the Malaysian national power company (TNB). The system is capable of determining the coordinates of the cloud-to-ground lightning strikes within 500m accuracy. However, for a localised distribution of lightning, say within 1 square km area, this accuracy is too large for the data to be meaningful

THE METHODS OF EVALUATION OF THE AIRCRAFT LOCATION USING MULTILATERATION SURVEILLANCE SYSTEM DATA

 Multilateration, also known as hyperbolic positioning, is the process of locating an object by accurately computing the time difference of arrival (TDOA) of a signal emitted from the object to three or more receivers. It also refers to the case of locating a receiver by measuring the TDOA of a signal transmitted from three or more synchronized transmitters

Software-only TDOA/RTF positioning for 3G WCDMA wireless network

A hybrid location finding technique based oil time difference of arrival (TDOA) with round-trip time (RTT) measurements is proposed for a wideband code division Multiple access (WCDMA) network. In this technique, a mobile station measures timing from at least three base stations using user equipment receive-transmit (UE Rx-Tx) time difference and at least three base stations measure timing from the mobile station using RTT. The timing measurements of mobile and base stations are then combined to solve for both the location of the mobile and the synchronization offset between base stations. A software-only geolocation system based on the above mobile/base stations timing measurements is implemented in Matlab platform and the performance of the system is investigated using large-scale propagation models

TDoA Based Positioning using Ultrasound Signals and Wireless Nodes

In this paper, a positioning technique based on Time Difference of Arrival (TDoA) measurements is analyzed. The proposed approach is designed to consent range and position estimation, using ultrasound transmissions of a stream of chirp pulses, received by a set of wireless nodes. A potential source of inaccuracy introduced by lack of synchronization between transmitting node and receiving nodes is identified and characterized. An algorithm to identify and correct such inaccuracies is presented.Comment: Preprin

Geolocation with FDOA Measurements via Polynomial Systems and RANSAC

The problem of geolocation of a transmitter via time difference of arrival (TDOA) and frequency difference of arrival (FDOA) is given as a system of polynomial equations. This allows for the use of homotopy continuation-based methods from numerical algebraic geometry. A novel geolocation algorithm employs numerical algebraic geometry techniques in conjunction with the random sample consensus (RANSAC) method. This is all developed and demonstrated in the setting of only FDOA measurements, without loss of generality. Additionally, the problem formulation as polynomial systems immediately provides lower bounds on the number of receivers or measurements required for the solution set to consist of only isolated points.Comment: This work has been submitted to the IEEE for possible publication. Copyright may be transferred without notice, after which this version may no longer be accessibl

Multi-Array 5G V2V Relative Positioning: Performance Bounds

We study the performance bounds of vehicle-to-vehicle (V2V) relative positioning for vehicles with multiple antenna arrays. The Cram\'{e}r-Rao bound for the estimation of the relative position and the orientation of the Tx vehicle is derived, when angle of arrival (AOA) measurements with or without time-difference of arrival (TDOA) measurements are used. In addition, geometrically intuitive expressions for the corresponding Fisher information are provided. The derived bounds are numerically evaluated for different carrier frequencies, bandwidths and array configurations under different V2V scenarios, i.e. overtaking and platooning. The significance of the AOA and TDOA measurements for position estimation is investigated. The achievable positioning accuracy is then compared with the present requirements of the 3rd Generation Partnership Project (3GPP) 5G New Radio (NR) vehicle-to-everything (V2X) standardization