Radar detection bands refer to particular frequency ranges of radio waves. They typically have a high and low range within the band. The bands used for police radar have been limited to X, K and Ka by the FCC.
- X band
X band's operating range is between 10.5 to 10.55 GHz. It's the older band used for speed detection, and has been essentially phased-out in many parts of the country. New Jersey is the only X band state left, though small pockets of these older detector guns exist throughout the country.
Most false alarms occur on X band frequencies. X band is also the easiest to detect, as it's only accurate within half a mile, but can be detected from 2-4 miles away or more.
- K band
K band ranges from 24.05 to 24.25 GHz. This radar band was the next progression when X band became easy to detect. False alarms are rare on K band, but they can occur more frequently as certain products (such as garage openers) move to K band frequencies. Detectable from 2 or more miles away.
- Ka band ("super wide Ka band")
Ka band ranges from 33.4 GHz to 36.0 GHz. The newest radar band to be used for speed detection, Ka has a wider frequency range that exceeds previous K band limits, and is often referred to as wideband Ka or super wide Ka band. Detectors only set to sense K band won't be able to detect Ka police radar. Ka has the fewest false alarms of any radar band. Detectable from 2 or more miles away.
Radar detector detectors (RDDs) are most frequently employed by police in areas where radar detectors are illegal. They scan for the frequencies leaked by your radar detector. RDDs can only indicate the presence of a detector, and cannot pinpoint your vehicle specifically unless you're the only one in the area of the RDD unit and your detector is powered on.
Radio frequency refers to the number of wave vibrations measured in cycles per second, or hertz (Hz). Radar frequencies are in the millions of cycles per second, or gigahertz (GHz). Particular frequency ranges are called "bands."
When talking speed detection, laser and lidar mean the same thing. Lidar is an acronym for Light Detection And Ranging; and behaves in similar ways to radar detection. Instead of a radio wave, concentrated light is pulsed at an object; the scattered return light is analyzed to determine vehicle speed.
Because laser beams are much faster and more concentrated than radar, it can be both more accurate and more difficult to detect. However, laser guns cannot be fired from a moving police cruiser.
Police pop detection radar is a practice where the radar gun is left in the hold position. Older always-on radar methods are easy to detect from great distances because the beam is consistent. Pop detection only broadcasts when the officer targets a specific vehicle with a radar pulse. Pop method is tricky to avoid when you're the only vehicle on the road, or when you're the first vehicle targeted.