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Localization Protocols for Wireless Sensor Networks
Published in Mohammed Usman, Mohd Wajid, Mohd Dilshad Ansari, Enabling Technologies for Next Generation Wireless Communications, 2020
Ash Mohammad Abbas, Hamzah Ali Abdul Rahman Qasem
Angle-of-arrival (AoA) is the angle between the direction of propagation between a reference direction and an incident wave. The reference direction is also called orientation, and it is the direction against which all AoAs are measured. A localization scheme based on AoA information between neighbors is proposed in Peng and Sichitiu (2006). The scheme utilizes the information from nodes that can be multiple hops away from it. We call the approach proposed in Peng and Sichitiu (2006) as Probabilistic Localization with Orientation Information (PLOI). The algorithm is probabilistic in the sense that the positions of nodes are estimated using probability distribution functions. It is assumed that the orientation of each sensor node is known a priori. Note that for the node whose orientation is known, there has to be two or more anchor nodes to estimate the position of the node. However, in a sparse WSN, the number of anchor nodes for each node might be less than two. Consequently, the location information obtained from anchors that are multiple hops away is required to be used so that each node is localized.
Advances in Millimeter Wave Propagation for 5G Mobile Communication Systems
Published in Athanasios G. Kanatas, Konstantina S. Nikita, Panagiotis Mathiopoulos, New Directions in Wireless Communications Systems, 2017
Millimeter-wave cellular can be realized with high-gain steerable antennas, which are necessary to compensate for the high propagation loss and to direct energy toward optimal directions that can exploit multipath and successfully complete a link. Measurements have shown that NLOS links are also feasible with appropriate beam steering, orienting Tx and Rx antennas at the best pointing angle and taking advantage of the spatially separated multipath. Phased antenna arrays or switched-beam antenna arrays can exploit beam steering to increase link gain. Future smart antenna arrays, possibly on-chip, will algorithmically determine the optimal AOA and AOD. One possible beam steering method is to use narrowband pilot tones that enable the prediction of the spatial location of multipath based on narrowband envelope cross-correlations (Samimi et al. 2013). However, in order to achieve highly directional patterns, large antenna arrays are necessary.
Vehicle Localization in GNSS-Denied Environments
Published in Chao Gao, Guorong Zhao, Hassen Fourati, Cooperative Localization and Navigation, 2019
Ramtin Rabiee, Ian Bajaj, Wee Peng Tay
Angle of arrival (AoA), sometimes called direction of arrival (DoA), is another source of information available for a wireless communication setup. The most common method to obtain AoA is by using an antenna array, the details of which are not covered in the scope of this chapter. But for completeness, if the orientation (or reference direction) is known, the receiver can find the absolute direction from which the transmitted signal from a known source/transmitter has been received. Therefore, as depicted in Figure 11.4a, the two absolute AoAs from two transmitters with known positions form a triangle and converge at a third vertex, which is the position of the receiver.
A fully integrated 2TX–4RX 60-GHz FMCW radar transceiver for short-range applications
Published in International Journal of Electronics, 2023
Dušan P. Krčum, Đorđe P. Glavonjić, Veljko R. Mihajlović, Lazar V. Saranovac, Vladimir M. Milovanović, Ivan M. Milosavljević
However, to be able to completely cover 3-D space, the direction-of-arrival becomes indispensable in real multi-target environments. Determination of the direction of the incident wave, or angle-of-arrival (AoA), is a widely used technique in modern sensing systems. Applications of the AoA are numerous: asset tracking, indoor navigation, geolocalization, and many RF systems such as Bluetooth, Wi-Fi, RFID, NFC, and radar utilize its benefits. A simple RoC consisting of one TX and one RX with a wide antenna beam cannot distinguish among multiple irradiated targets with the same distance and velocity at different angles relative to the RoC Hsiao et al. (2016). The multiple-input multiple-output (MIMO) concept applied on multi-channel RoC transceivers allows an efficient solution to this problem. The angular resolution of the MIMO RoC system is tightly connected with a number of MIMO paths. Scaling of CMOS and BiCMOS processes empowered multiple channels on the same die, even together with integrated antennas. This led to a significant breakthrough in MIMO RoC research and application in vast commercial areas during the last decade.
Use of real time localization systems (RTLS) in the automotive production and the prospects of 5G – A literature review
Published in Production & Manufacturing Research, 2022
Christoph Küpper, Janina Rösch, Herwig Winkler
The Angle of Arrival estimation (AOA – also called Direction of Arrival DOA) allows base stations to calculate the angle of arrival of the transmitted signal. For this, the base stations need antenna arrays (Xiong and Jamieson 2013). These antenna arrays can use the incoming or outgoing signal to determine the direction from which this signal was transmitted. Thus, the position in the plane can already be determined with two base stations (three for the determination in space) (Peng and Sichitiu 2006). The position of the base stations must be known (see Figure 7). Although the base stations and the target object do not have to be synchronized, the base stations are characterized by higher investment and energy costs. The accuracy is also influenced by noise, NLOS and multipath (Ma et al. 2018). The same concept can be used with the Angle of Departure (AOD). (Al-Kadi and Zorn 2020)
Enabling real-time and high accuracy tracking with COTS RFID devices
Published in International Journal of Image and Data Fusion, 2020
Zhou et al. (2011) proposed an approach using phase difference to detect the angle of arrival (AOA). It has been reported that the accuracy of AOA measurements could be 1.7° with a pair of antennas in a two-dimensional (2D) scenario. Theoretically, a tag’s 2D location can be estimated using two pairs of antennas. However, no positioning experiment was reported in Zhou et al. (2011). It is not necessary to obtain the AOA measurements by fixing antennas in pairs for positioning purposes. A general algorithm can be developed to estimate the tag’s location using the phase measurements and the requirement of antenna deployment can be relaxed.