RFID Localisation For Internet Of Things Smart Homes: A Survey

The Internet of Things (IoT) enables numerous business opportunities in fields as diverse as e-health, smart cities, smart homes, among many others. The IoT incorporates multiple long-range, short-range, and personal area wireless networks and technologies into the designs of IoT applications. Localisation in indoor positioning systems plays an important role in the IoT. Location Based IoT applications range from tracking objects and people in real-time, assets management, agriculture, assisted monitoring technologies for healthcare, and smart homes, to name a few. Radio Frequency based systems for indoor positioning such as Radio Frequency Identification (RFID) is a key enabler technology for the IoT due to its costeffective, high readability rates, automatic identification and, importantly, its energy efficiency characteristic. This paper reviews the state-of-the-art RFID technologies in IoT Smart Homes applications. It presents several comparable studies of RFID based projects in smart homes and discusses the applications, techniques, algorithms, and challenges of adopting RFID technologies in IoT smart home systems.Comment: 18 pages, 2 figures, 3 table

Accuracy evaluation of probabilistic location methods in UWB-RFID systems

The present project is focused on investigating the achievable accuracy of classical location methods commonly used in wireless and proposing an alternative location method based on combining two of them. The first part of the project studies the advantages and disadvantages of extending Ultra Wideband and Radiofrequency Identification technologies on some classical location methods. As a result of the study and with the goal of improving accuracy in indoor radio propagation channels, the Received Strength Signal-based location method and the Time Difference Of Arrival-based location method are selected to be combined in the alternative location method, including the proper channel models. This combined location method takes advantage of the virtues of each location method and combines information in order to improve the estimation of one target's position when locating in indoor channel. The second part of the project is devoted to analyse and simulate the modified RSS, TDOA and Combined location methods, considering the randomness of a real multipath fading channel. Results show that the Combined location method performs always the best accuracy. Specifically in analytical study, the combined location method provides a deterministic error of 24 cm which represents an improvement of 54% and 15% of the RSS and TDOA accuracies respectively. In the simulated study, results show that it is able to improve the accuracy up to 46% and 85% of the RSS and TDOA respectively in specific evaluated points

Positioning and Sensing System Based on Impulse Radio Ultra-Wideband Technology

Impulse Radio Ultra-Wideband (IR-UWB) is a wireless carrier communication technology using nanosecond non-sinusoidal narrow pulses to transmit data. Therefore, the IR-UWB signal has a high resolution in the time domain and is suitable for high-precision positioning or sensing systems in IIoT scenarios. This thesis designs and implements a high-precision positioning system and a contactless sensing system based on the high temporal resolution characteristics of IR-UWB technology. The feasibility of the two applications in the IIoT is evaluated, which provides a reference for human-machine-thing positioning and human-machine interaction sensing technology in large smart factories. By analyzing the commonly used positioning algorithms in IR-UWB systems, this thesis designs an IRUWB relative positioning system based on the time of flight algorithm. The system uses the IR-UWB transceiver modules to obtain the distance data and calculates the relative position between the two individuals through the proposed relative positioning algorithm. An improved algorithm is proposed to simplify the system hardware, reducing the three serial port modules used in the positioning system to one. Based on the time of flight algorithm, this thesis also implements a contactless gesture sensing system with IR-UWB. The IR-UWB signal is sparsified by downsampling, and then the feature information of the signal is obtained by level-crossing sampling. Finally, a spiking neural network is used as the recognition algorithm to classify hand gestures

Accuracy evaluation of probabilistic location methods in UWB-RFID systems

The present project is focused on investigating the achievable accuracy of classical location methods commonly used in wireless and proposing an alternative location method based on combining two of them. The first part of the project studies the advantages and disadvantages of extending Ultra Wideband and Radiofrequency Identification technologies on some classical location methods. As a result of the study and with the goal of improving accuracy in indoor radio propagation channels, the Received Strength Signal-based location method and the Time Difference Of Arrival-based location method are selected to be combined in the alternative location method, including the proper channel models. This combined location method takes advantage of the virtues of each location method and combines information in order to improve the estimation of one target's position when locating in indoor channel. The second part of the project is devoted to analyse and simulate the modified RSS, TDOA and Combined location methods, considering the randomness of a real multipath fading channel. Results show that the Combined location method performs always the best accuracy. Specifically in analytical study, the combined location method provides a deterministic error of 24 cm which represents an improvement of 54% and 15% of the RSS and TDOA accuracies respectively. In the simulated study, results show that it is able to improve the accuracy up to 46% and 85% of the RSS and TDOA respectively in specific evaluated points

WALLSY: The UWB and SmartMesh IP enabled Wireless Ad-hoc Low-power Localization SYstem

This paper follows the implementation of a proofof-concept localization system for GNSS-denied environments. WALLSY (Wireless Ad-hoc Low-power Localization SYstem) is a portable and modular Ultra Wide-Band (UWB) and Smart Mesh IP (SMIP) hybrid. WALLSY uses UWB two way ranging (TWR) to measure distances, which are then sent via the lowpower SMIP backbone network to a central hub for calculating coordinates of tracked objects. The system is highly flexible and requires no external infrastructure or prior knowledge of the installation site. It uses a completely nomadic topology and delivers high localization accuracy with all modules being battery powered. It achieves this by using a custom time-slotting protocol which maximizes deep-sleep mode for UWB. Battery life can be further improved by activating inertial measurement unit (IMU) filtering. Visualization of tracked objects and system reconfiguration can be executed on-the-fly and are both accessible to end users through a simple graphical user interface (GUI). Results demonstrate that WALLSY can achieve more than ten times longer battery lifetime compared to competing solutions (localizing every 30 seconds). It provides 3D coordinates with an average spatial error of 60.5cm and an average standard deviation of 15cm. The system also provides support for up to 20 tags

Bidirectional UWB Localization: A Review on an Elastic Positioning Scheme for GNSS-deprived Zones

A bidirectional Ultra-Wideband (UWB) localization scheme is one of the three widely deployed design integration processes ordinarily destined for time-based UWB positioning systems. The key property of the bidirectional UWB localization is its ability to serve both the navigation and tracking assignments on-demand within a single localization scheme. Conventionally, the perspective of navigation and tracking in wireless localization systems is viewed distinctly as an individual system because different methodologies were required for the implementation process. The ability to flexibly or elastically combine two unique positioning perspectives (i.e., navigation and tracking) within a single scheme is a paradigm shift in the way location-based services are observed. Thus, this article addresses and pinpoints the potential of a bidirectional UWB localization scheme. Regarding this, the complete system model of the bidirectional UWB localization scheme was comprehensively described based on modular processes in this article. The demonstrative evaluation results based on two system integration processes as well as a SWOT (strengths, weaknesses, opportunities, and threats) analysis of the scheme were also discussed. Moreover, we argued that the presented bidirectional scheme can also be used as a prospective topology for the realization of precise location estimation processes in 5G/6G wireless mobile networks, as well as Wi-Fi fine-time measurement-based positioning systems in this article.Comment: 30 pages, 12 figure