A radar detector is an electronic device that has been used by motorists, for decades, to detect if their speed is being monitored by police using a radar gun. It gave a driver sufficient warning to reduce his speed to avoid being ticketed for speeding.
In a general sense, only emitting technologies, like Doppler radar, or LIDAR (pulsed laser light) can be detected. Visual speed estimating techniques, like ANPR or VASCAR cannot be detected in daytime. There are also no reports that piezo sensors can be detected. LIDAR devices require an optical-band sensor, although many modern detectors include LIDAR sensors.
Most radar detectors detect signals across a variety of wavelength bands- usually X, K, and Ka. The past success of radar detectors was based on the fact that a radio-wave beam cannot be narrow-enough, so the detector usually senses stray and scattered radiation, giving the driver time to slow down. Based on a focused laser-beam, LIDAR technology does not suffer this shortcoming, however it requires precise aiming. Modern police radars incorporate formidable computing power, producing a minimum number of ultra-short pulses, reusing wide beams for multi-target measurement, which renders most detectors useless. But, mobile Internet allows GPS navigation devices, like Waze, to map police radar locations in real-time (see below).
Radar guns and detectors have evolved, over time, to counter each other's technology in a form of civilian electronic "warfare." For example, as new frequencies have been introduced, radar detectors have initially been "blind" to them, until their technology was updated. Similarly, the length of time and strength of the transmissions used by police have been lowered to reduce the chance of detection, which in turn has resulted in more sensitive (and expensive) receivers and more sophisticated software counter technology. For example, one of the better radar detectors available, the ESCORT MAX360, sells for $549.95, It features GPS, directional alerts, dual antenna front and rear, Bluetooth connectivity, voice alerts, OLED Display, and Escort Live.
The latest technology can be found in the new Valentine One, Generation Two or V1G2 radar detector. This device uses a military-developed surface acoustic wave dispersive delay line filter to rapidly process a wide range of frequencies simultaneously. (Note- The new filter increased the G2's processing rate by more than 100 times compared to the original V1). This unit is supposed to be much more effective than competitors' units that use GPS.
As previously stated, some radar detectors, like the ESCORT MAX360, have added GPS technology. This allows users to manually store the locations where police frequently monitor traffic, with the detector sounding an alarm when approaching that location in the future. This is accomplished by pushing a button and doesn't require coordinates to be entered. These detectors also allow users to manually store the coordinates of sites of frequent false alarms, which the GPS enabled detector will then ignore. The detector can also be programmed to mute alerts when traveling below a preset speed, limiting unnecessary alerts. Some GPS enabled detectors can download the GPS coordinates of speed monitoring cameras and red-light cameras from the Internet, alerting the driver that they are approaching the camera.
Detectors, however, are illegal in all vehicles in Virginia, Washington, DC, U.S. military bases, as well as in all commercial vehicles in Illinois, New York, New Jersey. Similarly, radar jammers are banned under federal rule, but laser jammers are not specifically banned except in the states of California,Illinois, Minnesota, Illinois, Minnesota, South Carolina, Oklahoma, Tennessee, Texas, Utah, and Virginia.
Most drivers, however, now feel that most radar detectors are useless because they are being beaten at their own game. And secondly, many don't seem to work well on modern roads. In the past when you got a radar detector, you could always count on it making its little chirping sounds and flashing its lights, whenever you passed an automatic door (outside a shopping mall or a grocery store, for instance) because the technology they used was relatively similar to the technology radar detectors search for. And that makes sense. But these days, it isn't just shopping malls. In 2020, virtually every modern vehicle on the road is equipped with blind spot monitoring, parking sensors, adaptive cruise control and lane keep assist. All of these systems seem to use some form of technology that makes a radar detector go crazy with flashing and chirping. The number
of false positives has gone from "annoying but acceptable" to "please shut up so I can listen to my music." If eight out of every nine radar detector chirps and flashes are fake, you start to simply not trust it. It’s like the old Aesop's Fable story of “The Boy who Cried Wolf.”
And it's not just the false positives. Modern radar detectors are expensive- and they're being beaten at their own game by much cheaper solutions. The best example of this, of course, is Waze- a mobile app that lets users report police presence (and other potential road dangers) so you know when to slow down in order to avoid a ticket. It is tremendously accurate and quick. Almost as quick as a radar detector, and certainly with fewer false positives. If you're cruising down the highway and Waze tells you there's a police car ahead, you're likely to slow down- a lot more so than if you're cruising down the highway and your radar detector goes off. When your radar detector goes off, the first thing you do is you start looking around for a car with adaptive cruise control.
So, the bottom line is that high end radar detectors, with the latest technology, are effective. However, if you want to save some money, use a mobile app, instead, to avoid those costly speeding tickets!