Wi-Fi Range Research Articles

RWiFiSLAM: Effective WiFi Ranging Based SLAM System in Ambient Environments

rWiFiSLAM: Effective WiFi Ranging Based SLAM System in Ambient Environments

Enabling resilient UAV swarms through multi-hop wireless communications

In the last decade, the popularity of UAVs, colloquially known as drones, has increased tremendously. Nowadays, drones are used in a wide range of use-cases, such as precision agriculture, surveillance, and photography. Many of these use-cases can be made more efficient if multiple UAVs are used cooperatively (i.e., in a swarm). To achieve this, communication between the UAVs is paramount. To ensure communication, many works rely on the existing infrastructure (e.g., 4G). However, in many rural areas, this infrastructure does not exist. In those cases, an ad hoc (Wi-Fi) network is the most adequate alternative. Yet, due to the limited communication range of Wi-Fi, it is not possible to let UAVs in a swarm to communicate over a long distance. To solve this issue a relay approach is necessary. Despite general solutions to relay messages between (mobile) nodes already exist, many UAV swarms rely on master–slave communication. Thus, a specific solution for this type of communication might be more efficient. Hence, in this work, we propose a strategy to efficiently relay messages for UAV swarms adopting the master–slave communication paradigm. Our approach seeks to introduce a very small message overhead to avoid congestion of the network, and to provide more bandwidth for the actual applications of the UAV swarm. We tested our approach using a realistic UAV simulator called ArduSim. Our results show that our approach is capable of detecting all the nodes in the network within a few seconds. Furthermore, we applied our message relay approach on an existing swarm application (where a swarm of UAVs had to follow a mission), and our results show that, now, the communication range of the UAVs can be much larger, without impacting other aspects of the mission (such as flight time).

Assessment of the influence of electromagnetic noise radiation in the WiFi range on the emotional state of the operator

Experimental studies of electroencephalograms of an operator located in conditions of electromagnetic noise radiation in the WiFi range were carried out. Electroencephalograms were recorded in standard leads Fp1, Fp2, F3, F4, C3, C4, P3, P4, O1, O2, F7, F8, T3, T4, T5, T6, Fpz, Fz, Cz, Pz, Oz. The quantitative parameters of the operator's emotional state, expressed by the power spectral density of the rhythmic components of the brain, as well as such information parameters as sample entropy, fractal dimension, Lempel-Ziv complexity, averaged for 10 subjects were analyzed. It has been shown that when exposed to radiation, the operator experiences depression. It has been shown that the trend of changes in the parameters of the spectral power density of theta, alpha, gamma rhythms, fractal dimension, Lempel-Ziv complexity, sample entropy in most leads of electroencephalograms coincides with the trend of changes in these parameters presented in the scientific literature in depression. It has been established that the operator experiences fear, which is determined by an increase in the fractal dimension parameter of electroencephalograms by no more than 0.4% relative to the background

A Multi-Channel Approach and Testbed for Centimeter-Level WiFi Ranging

A Multi-Channel Approach and Testbed for Centimeter-Level WiFi Ranging

Gesture-Controlled Surveillance Car

Abstract: In this proposed work, the gesture-controlled surveillance car is used for surveillance purposes. A surveillance robot is designed and implemented using an ESP32 cam module which can be used in various industry fields for surveillance purposes. The robot uses the ESP32 cam module which gives the user 360 views and 180 views of the robot. With the help of this user can control the user the robot in the user space. This ESP32 cam module is a Wi-Fi-based module. It works in the Wi-Fi range. The project consists of one 360-degree and one 180-degree servo motor for the tilt and pan operations. The robot also uses dc motors for its movement the robot. The gesture-controlled instructions are provided to the robot to control the locomotion of the robot. The user can control the surveillance using the Chrome interface. This robot can also be useful at excavation sites where human intervention is not possible and where this kind of robot comes into the picture in collecting, storing, and transmitting the data to the operator operating it from a distance.

CHILDREN ARE MORE EXPOSED TO ELECTROMAGNETIC RADIATION IN COVID-19 LOCKDOWN: A LITERATURE REVIEW

Introduction: The COVID-19 pandemic has significantly affected people's quality of life. Unfortunately, the epidemic continues in various variants and it remains unclear how long it will continue. Children staying at home in the COVID-19 quarantine spent hours in front of the screen with online education. In addition, since they could not go out, they spent their free time in front of the screen using social media, playing computer games or watching movies. The aim of this study is to investigate the effects of low-level electromagnetic radiation (EMR) that children are exposed to at home during the COVID-19 quarantine. Method: The research method is literature review. Results: Studies have shown that, during the quarantine period, children's use of telecommunication devices such as televisions, tablets, smartphones and computers greatly increases. It was determined that the range of radio frequency (RF), Wi-Fi, power lines, visible light and Bluetooth increased in the home environment. The electric and magnetic fields emitted from these devices contain EMR and can seriously harm the health of children, who are structurally more sensitive than adults. Conclusion: There are growing concerns that children staying at home during the COVID-19 pandemic will face health hazards in the future as they are more exposed to EMR.

Extending Wi-Fi Direct Single-Group Network to Multi-Group Network Based on Android Smartphone

Nowadays, a very widespread of smartphones, especially Android smartphones, is observed. This is due to presence of many companies that produce Android based phones and provide them to consumers at reasonable prices with good specifications. The actual benefit of smartphones lies in creating communication between people through the exchange of messages, photos, videos, or other types of files. Usually, this communication is through the existence of an access point through which smartphones can connect to the Internet. However, the availability of the Internet is not guaranteed in all places and at all times, such as in crowded places, remote areas, natural disasters, or interruption of the Internet connection for any reason. To create a communication between devices, it is resorted to creating an ad hoc network using Device-to-Device technology. Wi-Fi Direct technology offers a suitable platform for creating an ad hoc network, as it supports the speed and range of standard Wi-Fi. In this paper, a mechanism is proposed to build an infrastructure-less ad hoc network, through developing the Wi-Fi direct protocol for Android smartphones. This network provides users ability to have a reliable communication, using the reliable Transmission Control Protocol only, and can continuously expand. Therefore it would be very beneficial in the absence of other infrastructure communication media such as cellular or Wi-Fi internet access.

Bridging the Performance Gap Between Two-Way and One-Way CSI-Based 5 GHz WiFi Ranging

Bridging the Performance Gap Between Two-Way and One-Way CSI-Based 5 GHz WiFi Ranging

Simultaneous WiFi Ranging Compensation and Localization for Indoor NLoS Environments

Smartphone-based WiFi ranging using fine time measurement (FTM) is severely impacted by Non-line-of-sight (NLoS) environments, which causes significant positioning errors. To address this problem, we propose a novel WiFi FTM positioning (WFP) approach based on the geomagnetism and enhanced genetic algorithm (EGA), which can simultaneously execute WiFi localization and ranging compensation. Based on the distribution of the ranging error in NLoS environments, a semiparametric error model-based ranging compensation method is proposed. To construct the EGA searching model, geomagnetism-based positioning is adopted and fed to the EGA together with the measured WiFi ranging data and the ranging compensation method. During online localization, the EGA model dynamically compensates for the erroneous ranging data until it finds the optimal position. Experimental results show that the ranging and localization accuracy of this EGA-based WFP are 1.33 m and 1.64 m, being an improvement of 30.7% and 56.5% compared to the uncompensated ranging data and the trilateration algorithm using the weighted least square (WLS) method, respectively.

Performance Analysis of Wearable Dual-Band Patch Antenna Based on EBG and SRR Surfaces.

This paper presents the performance comparison of a dual-band conventional antenna with a split-ring resonator (SRR)- and electromagnetic bandgap (EBG)-based dual-band design operating at 2.4 GHz and 5.4 GHz. The compactness and dual-frequency operation in the legacy Wi-Fi range of this design make it highly favorable for wearable sensor network-based Internet of Things (IoT) applications. Considering the current need for wearable antennas, wash cotton (with a relative permittivity of 1.51) is used as a substrate material for both conventional and metamaterial-based antennas. The radiation characteristics of the conventional antenna are compared with the EBG and SRR ground planes-based antennas in terms of return loss, gain, and efficiency. It is found that the SRR-based antenna is more efficient in terms of gain and surface wave suppression as well as more compact in comparison with its two counterparts. The compared results are found to be based on two distinct frequency ranges, namely, 2.4 GHz and 5.4 GHz. The suggested SRR-based antenna exhibits improved performance at 5.4 GHz, with gains of 7.39 dbi, bandwidths of 374 MHz, total efficiencies of 64.7%, and HPBWs of 43.2 degrees. The measurements made in bent condition are 6.22 db, 313 MHz, 52.45%, and 22.3 degrees, respectively. The three considered antennas (conventional, EBG-based, and SRR-based) are designed with a compact size to be well-suited for biomedical sensors, and specific absorption rate (SAR) analysis is performed to ensure user safety. In addition, the performance of the proposed antenna under bending conditions is also considered to present a realistic approach for a practical antenna design.

DiverSense

The ubiquity of Wi-Fi infrastructure has facilitated the development of a range of Wi-Fi based sensing applications. Wi-Fi sensing relies on weak signal reflections from the human target and thus only supports a limited sensing range, which significantly hinders the real-world deployment of the proposed sensing systems. To extend the sensing range, traditional algorithms focus on suppressing the noise introduced by the imperfect Wi-Fi hardware. This paper picks a different direction and proposes to enhance the quality of the sensing signal by fully exploiting the signal diversity provided by the Wi-Fi hardware. We propose DiverSense, a system that combines sensing signal received from all subcarriers and all antennas in the array, to fully utilize the spatial and frequency diversity. To guarantee the diversity gain after signal combining, we also propose a time-diversity based signal alignment algorithm to align the phase of the multiple received sensing signals. We implement the proposed methods in a respiration monitoring system using commodity Wi-Fi devices and evaluate the performance in diverse environments. Extensive experimental results demonstrate that DiverSense is able to accurately monitor the human respiration even when the sensing signal is under noise floor, and therefore boosts sensing range to 40 meters, which is a 3x improvement over the current state-of-the-art. DiverSense also works robustly under NLoS scenarios, e.g., DiverSense is able to accurately monitor respiration even when the human and the Wi-Fi transceivers are separated by two concrete walls with wooden doors.

Development of WARKS for Accessing Supply-Chain Management

In our modern society, the demand of wireless communications increases exponentially. All the indoor and outdoor everything converting from wire to wireless. Even the newly invented devices, cars, TV, refrigerator, washing machine all the advanced things uses wireless technology. Because of the reason, there are more fields to do research in this area. WiFi is one of the important technology in wireless communications. In this work, we have developed a device which will useful to build an wireless network. The device used to monitor and to control supply-chain management of any organization. We have used WiFi which works as two different modes; one is AP (Access Point) and another is STA (STAtion). In this paper, AP acts as a Server where STA act as a Client. We have developed a wireless network system using self organized sensor nodes (each node has one AP, one STA and one Controller) to communicated each other serially to exchange data and request task accordingly. Because of its serial distributed formation the WiFi range is also be increased with different topology. All the command and request can be done using computer or smartphone. This system (we named it WARKS) can be implemented in home, industrial, hospital, farms, forest, agriculture and many more. To verify the system capabilities and work performance, we do the experiment in indoor and outdoor using required hardware and software.

Analysis and Enhancement of Q-Factor in Thin-Film Bulk Acoustic Wave Resonator (FBAR)

In MEMS technology, MEMS Resonators has shown high potential applications in wireless communications such as Bluetooth and WIFI range. The Bulk Acoustic Wave (BAW) Resonator is a device which has more potential to meet the needs of today’s wireless technology. The Acoustic wave technology has attracted more attention and it’s an effective solution for achieving high-performance RF filters applications due to its low cost and small size of the device. The performance analysis of thin film bulk acoustic resonator (FBAR) by varying different piezoelectric material, piezoelectric material’s thickness and electrode materials is demonstrated in this paper. It is understood that the Quality factor is considerable higher for AlN as compared to ZnO and LiNbO3. Among all the materials, Aluminium electrode achieved maximum quality factor. As the thickness of piezo material decreases, it is found that the resonant frequency and Quality factor increases. Along with the Quality Factor, the top and bottom electrode thickness has a significant impact on the resonant frequency.

Wireless Android-Based Control of Plastic Crane Roll Control Prototype

Abstract - Overhead crane is a lifting tool used by almost all industries, ports, warehouses, workshops, and others. In general, the overhead crane control system is less effective and efficient because the operator still follows the direction of the crane's speed. In this case, problems often occur because the pendant switch which functions as a controller still uses a cable as a connector to the overhead crane panel. Various problems that often occur include cables breaking frequently due to being hit by a load lifted by the hoist, operators having difficulty setting a safe distance because they are limited by the length of the pendant switch cable. Based on the background of the problem, a control system is made which is expected to be able to control the overhead crane effectively and efficiently without using a cable as a connector but using an android smartphone. Control with an android smartphone using an android application with a wifi connection and an arduino uno R3 microcontroller. Based on the test results on this control system, device control can be controlled at a maximum distance of ± 100 meters as long as the device is still within wifi range. The control system can function optimally and the application can be installed on Android OS 4.0 (Jelly Bean) smartphones. Therefore, the use of a cable can be replaced with a wifi connection system to reduce friction with the cable and so that the operator can maintain a safe distance from the load to be moved because it is no longer limited by the length of the cable.

Fully Automated Aqua Farm Monitoring System

Water quality of pond is the major issue in the aquaculture. There will be several parameters which are cause for change in water quality. Some of them include turbidity, water level, temperature, pH values, ammonia etc. For the past few years people came up with different techniques and methods to monitor water quality. In our research we are focusing on the three major parameters i.e., Turbidity, Temperature and pH, which may constitute a major role in polluting the pond water. So by using IoT technology (using various) we have implemented a system to monitor the water parameters continuously. In addition to that we proposed a methodology where the data received from the sensor is analyzed and will trigger actions based on some conditions. Our system will be able to monitor the parameter in real-time continuously with the capability of record and analyze each reading in a more efficient way using things speak platform. In this work, we have outlined and actualized monitoring of pond health continuously utilizing Arduino, various Sensors like turbidity sensor, temperature sensor, humidity sensor, pH sensor. In this work, we have also implemented mobile notification system where a user can monitor the water condition using mobile through Wi-Fi within Wi-Fi range and through Internet from anywhere in the world.

Rotatable WIFI Security Camera using ESP32 Cam

The security cameras like CCTV (Closed Circuit Television) are tools that can minimize theft in both private homes and public places. But the problem with most of the CCTV and security cameras are that they are not having the mechanisms that can be used to monitor the place at an angle that is difficult to reach by a CCTV camera, i.e. they cannot be panned and tilted to reach an angle that is difficult to reach. Also, the CCTV cameras are not portable, are not wireless and requires a dedicated systems in order to be operable. In this study, a simulation tool was designed that combines an ESP32 Camera Module, that can be programmed using Arduino IDE, with 180 degree rotatable SG90 servo motors, in order for it to rotate horizontally and vertically. Its cost is significantly lesser than the cost of a moving CCTV camera, and it can be controlled from anywhere in the house within the WIFI range and its wireless. And with this simulation can be an alternative of CCTV cameras. Also, the requirement for a dedicated system and a dedicated person for the surveillance is absent, as it can be accessed from anyone having the WIFI credentials and within the range of the wifi network. Dedicated system is not required as it only needs a smartphone or PC/laptop for viewing camera footage

A Review on Smart Home Using IoT

Mobile gadgets have become an integral part of our daily lives. The last several years. As a result, providing facilities and services is essential. On the internet, security is becoming more important. Android mobile interacts with automated system devices. The system and mobile device may communicate with one another. Wi-Fi allows them to communicate with one another. The smartphone app may be downloaded and connected to the system from any device that is suitable. Lights, fans, and other electrical equipment may be turned on and off using commands. Air conditioners, etc., as well as setting a timer at home or anywhere else from a mobile device, an organization may be delivered fast and simply. Devices through a user-friendly graphical user interface (GUI), which is any average user will find it simple to use. After that, the system takes action. Respond to these commands by performing the actions specified in the commands and informs the user of the outcome is also visible to the user. Within the Wi-Fi range of an Android mobile application. As a result, designing a home automation system is a good choice. A luxury lifestyle aimed at creating a cutting-edge house Wi-Fi technology is used to create an automation system.

The influence of Wi-Fi range electromagnetic radiation on the parameters of the human’s heart variability

The issue of the effect of Wi Fi range (WFR) electromagnetic radiation (EMR) on the human’s body has recently become topical due to a considerable growth of the abundance and exposition of this factor. The energy evaluation of the influence is a complicated task due to the phenomenon of superposition of multitude Wi Fi sources, effecting humans simultaneously. The paper studies the effect of the Wi Fi source’s electromagnetic radiation on the cardiovascu lar and vegetative nervous systems of the human. The effect of the WFR electromagnetic radiation, being expressed by the reliable change in the parameters of the heart rate variability (HRV), on the cardiovascular system state was studied. The results the reliable influence of WFR on the HRV parameters on the background of the psycho emotional load was exposed; the HRV parameters included the mode (Mo), an average heart rate (HR) and the coefficient of the variation (CV). The changes of the indicator of the regulation processes’ adequacy demonstrate regulatory mechanisms’ decentralization under the complex influence of factors. The index of the regulatory systems’ tension increases during the combined influence of WFR and psycho emotional load, ipso facto, v iolating the adequate regulatory reaction of the body towards the decrease of the adaptive abilities.

Remote control system for the unmanned floating platform

The paper presents the results of modelling the coverage areas of a communication system in the Wi-Fi range for organizing a wireless data transmission channel between the coastal and onboard control subsystems of an unmanned floating platform, for which the main navigation zones near the coast are determined. It is shown that the use of a communication system based on the IEEE 802.11 standard makes it possible to ensure stable data exchange within the specified navigation zones of the unmanned platform. A generalized block diagram of a remote control system for an unmanned floating platform has been developed. It includes a video surveillance subsystem and a subsystem for engine control and collection of metrological data from various sensors. In this case, the floating platform is controlled both from a stationary post and using a mobile console. Functional diagrams of the onboard video surveillance and control system, as well as the coastal subsystem have been developed.

Calibration-Free Positioning Technique Using Wi-Fi Ranging and Built-In Sensors of Mobile Devices

As positioning solutions integrate multiple components to improve accuracy, the number of parameters that require calibration has increased. This article studies a calibration-free positioning technique using Wi-Fi ranging and pedestrian dead reckoning (PDR), where every parameter in the system is optimized in real time. This significantly decreases the time and effort required to perform manual calibration procedures and enables the positioning solution to achieve robust performance in various situations. Additionally, this article studies an efficient way of performing irregular Wi-Fi ranging procedures to improve battery life and network performance of mobile devices. The positioning performance of the proposed method was verified using a real-time Android application on several mobile devices under a large indoor office environment. Without any calibration, the proposed method achieved up to 1.38-m average positioning accuracy for received signal strength (RSS)-based ranging scenarios, which differs only by 30 cm from the benchmark assuming perfect calibration. In addition, the proposed method achieved up to 1.04-m accuracy for round trip time (RTT)-based ranging scenarios with a 40-MHz bandwidth configuration, which differs only by 10 cm from the benchmark.