Passive technology-based vehicle speed measurement method and system for two sides of road

Abstract

The invention discloses a passive technology-based vehicle speed measurement method and system for two sides of a road. A received signal strength value RSS is changed due to the fact that a vehicle enters and leaves a speed measurement area to shield two wireless communication links of an entrance boundary and an exit boundary; the length of a sliding window is dynamically selected according to the estimated vehicle speed, RSS variances of an entrance boundary wireless communication link and an exit boundary wireless communication link of the vehicle are calculated, the time when the vehiclejust enters and is about to leave the speed measurement area is found out through sudden change points of the variances, and the vehicle speed is calculated according to the known length of the speedmeasurement area; the RSS signals of the wireless communication link acquired by the monitoring nodes in the speed measurement area can be applied to vehicle speed measurement in multiple fields, andmeanwhile, the signals are scanned and acquired by adopting multiple channels among the monitoring nodes, so that the vehicle speed can still be measured even if a certain channel generates large interference, and the vehicle speed measurement precision is favorably improved.

Description

technical field [0001] The invention belongs to the field of vehicle speed measurement, in particular to a vehicle speed measurement method and system based on passive technology on both sides of a road. Background technique [0002] Radio Tomographic Imaging (RTI, Radio Tomographic Imaging) is a passive positioning technology based on wireless sensor networks. positioning and tracking. Compared with the traditional active positioning system, the passive positioning technology only needs to deploy several wireless sensor nodes around the monitoring area to form a communication network, without the need for the target to carry any electronic tags to complete the positioning and tracking of the target. [0003] Currently, vehicle speed measurement is widely used in road traffic and national defense land battlefields and other fields. Common vehicle speed measurement methods include video speed measurement, induction coil speed measurement, radar speed measurement, ultrasonic...

AI Technical Summary

Problems solved by technology

Although laser speed measurement is theoretically feasible, there are safety problems in the process of use

Radar speed measurement is easily affected by environmental weather

Other wireless sensor speed measurement is mostly based on active positioning technology, which requires the vehicle itself to carry an electronic tag, which is difficult to be popularized and applied in practice

[0004] The current vehicle speed measurement technology based on radar, laser and machine vision is not only costly, but also vulnerable to environmental weather and cannot work around the clock, nor can it measure the speed of the target through obstacles

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