Evaluation of a Wi-Fi Signal Based System for Freeway Traffic States Monitoring: An Exploratory Field Test

Abstract

Monitoring traffic states from the road is arousing increasing concern from traffic management authorities. To complete the picture of real-time traffic states, novel data sources have been introduced and studied in the transportation community for decades. This paper explores a supplementary and novel data source, Wi-Fi signal data, to extract traffic information through a well-designed system. An IoT (Internet of Things)-based Wi-Fi signal detector consisting of a solar power module, high capacity module, and IoT functioning module was constructed to collect Wi-Fi signal data. On this basis, a filtration and mining algorithm was developed to extract traffic state information (i.e., travel time, traffic volume, and speed). In addition, to evaluate the performance of the proposed system, a practical field test was conducted through the use of the system to monitor traffic states of a major corridor in China. The comparison results with loop data indicated that traffic speed obtained from the system was consistent with that collected from loop detectors. The mean absolute percentage error reached 3.55% in the best case. Furthermore, the preliminary analysis proved the existence of the highly correlated relationship between volumes obtained from the system and from loop detectors. The evaluation confirmed the feasibility of applying Wi-Fi signal data to acquisition of traffic information, indicating that Wi-Fi signal data could be used as a supplementary data source for monitoring real-time traffic states.

Design and Implementation of Cloud Analytics-Assisted Smart Power Meters Considering Advanced Artificial Intelligence as Edge Analytics in Demand-Side Management for Smart Homes

“…Wireless communication technology such as Bluetooth [37], ZigBee [38], and Wi-Fi [39,40,41] can be conducted and used for the presented prototype in the described architecture in this work. ZigBee (the Institute of Electrical and Electronics Engineers (IEEE) 802.15.4 standard) [38] is arguably the most popular technology for creating wireless sensor networks, and it was included in some of the latest commercial [40] and academic home automation cases, including water pump control in a smart fish farm with efficient energy consumption [15,42,43], and several others [39,40,44]. The new Android smartphone application that uses the open-source Massachusetts Institute of Technology (MIT) App Inventor 2 software to monitor voltage and current measurements in Reference [37] can also be conducted, developed, and used by the presented prototype in the described architecture.…”

A Smart Autonomous Time- and Frequency-Domain Analysis Current Sensor-Based Power Meter Prototype Developed over Fog-Cloud Analytics for Demand-Side Management

“…Wireless communication technology such as Bluetooth [22], ZigBee [42], Wi-Fi [43,44], and 2G General Packet Radio Services (GPRS) [45] can be conducted and developed in the architecture in Figure 3. In this sense, the WIZNet W5100 hardwired TCP/IP embedded Ethernet shield mounted on the Arduino MEGA 2560 MCU, the core entity of the designed and implemented smart prototype shown in Figure 4 can be replaced with an ESP8266 ESP-01 system-on-a-chip (SoC) Wi-Fi microchip or an ESP8266 ESP-12E Wi-Fi SoC NodeMCU [46] where advanced AI well trained offline in cloud analytics can be autonomously and automatically deployed onsite on the NodeMCU as edge analytics via the over-the-air programming.…”

An Innovative and Cost-Effective Traffic Information Collection Scheme Using the Wireless Sniffing Technique

“…Ding et al [14] used Wi-Fi signals to observe the speed and traffic flow of the highway field, and VD data were used as the ground truth. The result shows the traffic flow would be overestimated or underestimated in some cases.…”