The battle is raging between police officers and speeders as they continually try to one-up the other with new technology (Corbis).

    by: Rex Roy | AOL Autos

    People speed for plenty of reasons. Some claim they’re in a hurry. Some aren’t paying attention. Some do it for sport. Likewise, police have multiple motivations for ticketing speeders. Some officers claim driving anything over the speed limit is "unsafe." Some departments do it to fill municipal coffers hit hard by falling tax revenues. And yes, some do it for sport.

    Regardless of why drivers speed and cops ticket, each side is using technology to increase their chances of success.

    How Radar Works

    Back in the old days, officers “paced” speeders, following behind at a constant distance or timed speeders between two fixed points, calculating speed by dividing the distance by the elapsed time. The latter technique is still employed, particularly when aircraft are used in traffic enforcement. The invention of radar, however, changed the speeding game.

    First used by the British in World War II, the operational concept of radar is simple: Radar essentially uses echoes and the Doppler shift to measure the size, speed, and even the contours of an object within its range. The ability to measure speed is what interests the police.

    A Passport 9500ix radar detector (Escort Radar).

    Their units emit radio waves that the operator aims at traffic. The waves bounce off the oncoming vehicle, causing an echo. The frequency of this echo can be measured by the radar gun. Because of what's known as the Doppler shift, an object moving more quickly toward the radar gun will reflect an echo of a higher frequency than one moving more slowly. The relative changes in echo frequency give the radar guns the data they need to calculate the target's speed.

    The first police radar system debuted in 1947 and operated on S-Band (2.445 gigahertz), a frequency close to that of today's microwave ovens. The stationary-use, 45-pound units weren't particularly practical or accurate and their effective range was less than 200 feet. The next stage of development occurred in the mid-1960s with X-band systems (10.525 GHz). These newer units ruled the country's new Interstate system throughout the 1970s. The K-band (24.150 GHz) became more common after 1976, and the Ka-band (33.4-36 GHz) appeared in 1989. Because of their shorter waveform, these newer K-band frequencies enabled the radar units to operate with greater accuracy. Some 41 state police departments now utilize Ka-band radar systems. Reportedly, there are some 300,000 radar guns in operation across the US.

    Today's police radar units can be stationary or mobile. They have the ability to clock traffic approaching the radar gun or driving away from the operator. Radar manufacturers recommend a maximum target range of around 700 feet, but the units are capable of locking onto a target at up to a quarter-mile if conditions are ideal. 

    Vintage Fuzzbuster radar detector (Wikipedia).

    As advanced as police radar has become, the units have some drawbacks. While fast, the emitting of waves and processing the echo can take the unit's computer seconds to lock in and register. This can take even longer if there are multiple targets, such as one might experience in traffic. The other problem is that when operating at 1000 feet, the radar "beam" can be 200 or more feet wide. This large coverage area reduces accuracy and can make it difficult for an officer to identify the target the radar unit has locked onto. Metal fencing, microwave radio towers, and other objects can cause also reflective interference and inaccurate radar readings.

    How Laser Detectors Work

    Laser or LIDAR (Light Detection And Ranging) equipment is the newest trick employed by police. Laser detection equipment works by aiming a narrow beam of infrared light at a vehicle, and then measuring how long it takes to reflect back to the unit. The computer in the laser unit divides the time by two and calculates the vehicle's distance. It then immediately repeats the process, comparing the change in distance to determine the vehicle's speed.

    A burst from a laser gun can include as many as 1,000 samples per second, helping insure the accuracy of the measurement. Additionally, the beam of infrared light maintains its narrow focus, so it targets vehicles with pinpoint accuracy. From 1,000 feet, a laser beam measures just three feet wide. In other words, when an officer aims at a vehicle with a laser, chances are he’ll get his reading.

    One drawback of laser is that it must be fired from a stationary location. Unlike radar, laser cannot be shot through glass, and lasers are also impacted by rain, fog, dust or smoke.

    Fuzzbusters and Other Countermeasures

    Do you use a "fuzzbuster" or similar device in your car?

    While the first police radar systems came into use in the late 1950s, it wasn’t until the ’70s that speeders became armed with the first electronic countermeasures. Older drivers might remember the Fuzzbuster and Super Snooper, two of the earliest commercially marketed radar detectors. In contrast to the svelte, compact shapes of modern units, the first detectors looked like bulky, crudely built science fair projects.

    Modern radar and laser detectors employ carefully shaped antennas to receive radio and light waves. When frequencies match those known to be used by police radar and laser units, the detectors signal an alert. But it’s not so simple, because police aren't the only ones using the airwaves. Sensors that operate automatic doors at grocery stores also use various radar bands, as do garage door openers and traffic-flow monitoring systems.

    Most units today combine radar and laser detection in one device, and conventional wisdom says a higher price tag corresponds with improved performance. The better detectors tend to do a superior job of filtering out non-police signals than cheaper units, and some models have built-in GPS, to help recognize and remember the locations of fixed-location “false alarms.” One of the newest features being incorporated into the devices is unmanned photo radar and red-light intersection camera detection, often working in conjunction with a Web-based database of these locations.

    "Instant On"

    The major shortcoming of driving with a detector, even a top-of-the-line model, is that there is almost no advanced warning when police use instant-on radar units or laser. If you get popped by instant-on radar, it's likely too late to slow down. Hearing an alert for laser is an even more dire situation, because the speed at which lasers operate means that by the time the detector sounds an alert, the laser gun is already showing the cop how fast you are travelling.

    Keep in mind that radar detectors are illegal in Virginia and Washington, D.C., as well as parts of Canada. To sniff out citizens using the radar detectors, a manufacturer of radar and LIDAR units also produces a radar detector "detector." This works because all modern radar detectors use a component called an oscillator, which emits a measurable amount of electromagnet "leakage.” This is what the detector detector detects.

    Catching on to the pattern here? This is most certainly war.

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    1 - 20 of 354 Comments
    jmak118 Nov 30, 2010 7:37 PM
    couple of points... 1. when you need a cop, where are they? making quotas? i live in a small town 1 stop light, like lots of readers. do some research, you'll find the biggest tax drain on your property is your police department. you will find that the cost for the p.d. outweighs the budget for your vol. fire dept and the highway department combined. you'll also find, you have a county sheriff you are also paying for. when was the last time you saw a sheriff car? 4th of july parade. and your property taxes, just keep going higher and higher, every year. how about your wages? it isn't cost effective. quotas low? who they gonna ticket? the hand that feeds them. in n.y.s. you get a ticket. guilty or not, you will pay a surcharge, between 50 and 80 bucks. you walked? great, you paid the surcharge. kind of like paying the p.d... a tip?
    Report This
    tectvguy Nov 21, 2010 4:01 PM
    While one can not transmit to jam radar per FCC law one CAN transmit IR (Infrared) to jam laser.
    Report This
    kx00000000010777 Nov 01, 2010 3:46 AM
    You have no choice but to slow down or get ticketed. Did you know major insurance companies fund "traps" and purchase LIDAR and RADAR for police departments around the country? Higher justifiable premiums are always a plus for insurance companies!
    Report This
    mrdcc2 Sep 28, 2010 6:04 AM
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    ademnt5 Sep 28, 2010 12:48 AM
    whay alot of company dont care about dot , it gona be bad
    Report This
    jch5094089 Sep 27, 2010 11:05 PM
    what the h@ll. Speed if you want to. Who gives a sh*t!!
    Report This
    crownedvicky Sep 27, 2010 10:45 PM
    why is there a "fast" lane if you'll just get a ticket in the end...somethings need to change around here...and a slow ******* prius' ain't the change i'm talkin about niether...
    Report This
    twofirst1 Sep 27, 2010 9:43 PM
    Ya the only problem is who is going to pay for the new police cars and the police's salaries all the tax dollars are going to pay for the illegals and thier college education and the illegals and thier hospital medical bills and feed them and shelter them Here in the USA everything is free for the non American Citizens of other countries and especially if they are not taxpayers.....Just ask a Federal Judge that makes 250,000.00 a year and lives real good at the taxpayers expense.....Oh I forgot to mention the greedy liberal politicians still haven't figured it out HUH....Who is left to pay thier salaries?????? Financial meltdown of the USA...
    Report This
    drhrosa Sep 27, 2010 9:21 PM
    Everyone is a dumb driver. EVERYONE.
    Report This
    kimfont2066 Sep 27, 2010 8:27 PM
    nothing lamer then local suburban cops sitting around trying to justify their existence with speeding tickets.
    Report This
    catin94sc Sep 27, 2010 7:08 PM
    phantom2 nuff said
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    timmccusker4500 Sep 27, 2010 6:30 PM
    If you want to drive the speed limit or a little less thats fine ...JUST STAY OUT OF THE LEFT LANE... If you are a rubber necker thats fine... JUST STAY OUT OF THE LEFT LANE......... If you slow down when it rains, snows, or in fog thats fine..... JUST STAY OUT OF THE LEFT LANE.... If you don't keep up on all your car's maintenance ie. Tire's, Brake's, suspention etc. JUST STAY OUT OF THE LEFT LANE........ THE LEFT LANE IS FOR PEOPLE WHO KNOW HOW TO DRIVE LIKE A PRO, "NOT JUST ANY JOE"....... People who don't drive like thier and other people's lives depend on it...... are NOT PRO'S.....
    Report This
    sgentilejr Sep 27, 2010 5:15 PM
    If you all slowed down to the speed limit or even a little below the speed limits___there would be far less fine money being collected that is used to place more and more police officers on the payrolls and pay for speed cameras. A 60 mile trip___in a 60MPH zone takes 60 minutes at 60MPH. The same 60 mile trip__in the same 60MPH zone when doing 70MPH takes 55 minutes. Is saving 5 minutes worth risking at $400 fine and higher insurance premiums? Plus vehicles use 10 to 20% less fuel per mile driven at 60MPH compared to 70MPH.
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    kpontusa1 Sep 23, 2010 6:03 AM
    I have a Tom-Tom, I got it because Chevy wanted $500 to fix their electrical issues that should have been a recall, but they decided to send everyone a letter, so it's my $50 solution (middle finger to GM) for an operable speedometer... ******** secondary features have saved me a bundle. It warns me of stationary radars and red light cameras and because it screams at me when I go 3mph over the posted limit, it catches those sudden, but often not well marked drops in the speed limit. Additionally, I noticed that when I am in a hurry or stressed is when I seem to get screamed at a lot by it. I don't intend to speed, but if I'm up there and I notice it, I'm more likely to blow it off and keep my speed, but if I'm only slightly over, I slow it down a few. That said, when helping a friend setting up their home base CB, I became aware that we had to watch his output or it could damage nearby receivers. So it seems feasible that you could build a device to detect the incoming radar signal and return white noise at that frequency, only 10, 100 even a thousand-fold the original signal and destroy their receiver.
    Report This
    irish72690 Sep 14, 2010 11:28 PM
    do the speed limit.
    Report This
    slater259 Aug 30, 2010 6:04 PM
    Radar/Laser detectors are a waste of money. Chances are the cops will have his radar/laser off until he sees you speeding and then hits you with it. Like the article said, by this time it is too late. He has a reading just as your detector goes off. Just get a 1000rr Honda Sport bike. Top speed 186mph cops can't keep up with it. Oh, and speed doesn't kill, idiots on cell phones talking and texting do.
    Report This
    snickers23185 Jul 24, 2010 4:59 PM
    As you may know, Virginia is the only state that bans the use and sale of detectors. There is no evidence that the detector ban increases highway safety. Our nations fatality rates have fallen consistently for almost two decades. Virginias fatality rate has also fallen, but not any more dramatically than it has nationwide. Research has even shown that radar detector owners have a lower accident rate than motorists who do not own a detector. Maintaining the ban is not in the best interest of Virginians or visitors to the state. I know and know of people that will not drive in Virginia due to this ban. Unjust enforcement practices are not unheard of, and radar detectors can keep safe motorists from being exploited by abusive speed traps. Likewise, the ban has a negative impact on Virginias business community. Electronic distributors lose business to neighboring states and Virginia misses out on valuable sales tax revenue. Radar detector bans do not work. Research and experience show that radar detector bans do not result in lower accident rates, improved speed-limit compliance or reduce auto insurance expenditures. The Virginia radar detector ban is difficult and expensive to enforce. The Virginia ban diverts precious law enforcement resources from more important duties. Radar detectors are legal in the rest of the nation, in all 49 other states. In fact, the first state to test a radar detector ban, Connecticut, repealed the law it ruled the law was ineffective and unfair. It is time for our Virginia to join the rest of the nation. It has never been shown that radar detectors cause accidents or even encourage motorists to drive faster than they would otherwise. The Yankelovich Clancy Shulman Radar Detector Study conducted in 1987, showed that radar detector users drove an average of 34% further between accidents (233,933 miles versus 174,554 miles) than non radar detector users. The study also showed that they have much higher seat belt use compliance. If drivers with radar detectors have fewer accidents, it follows that they have reduced insurance costs it is counterproductive to ban radar detectors. In a similar study performed in Great Britain by MORI in 2001 the summary reports that "Users (of radar detectors) appear to travel 50% further between accidents than non-users. In this survey the users interviewed traveling on average 217,353 miles between accidents compared to 143,401 miles between accidents of those non-users randomly drawn from the general public." The MORI study also reported "Three quarters agree, perhaps unsurprisingly, that since purchasing a radar detector they have become more conscious about keeping to the speed limit..." and "Three in five detector users claim to have become a safer driver since purchasing a detector." Modern radar detectors play a significant role in preventing accidents and laying the technology foundation for the Safety Warning System (SWS). Radar detectors with SWS alert motorists to oncoming emergency vehicles, potential road hazards, and unusual traffic conditions. There are more than 10 million radar detectors with SWS in use nationwide. The federal government has earmarked $2.1 million for further study of the SWS over a three-year period of time. The U.S. Department of Transportation is administering grants to state and local governments to purchase the SWS system and study its effectiveness (for example, in the form of SWS transmitters for school buses and emergency vehicles). The drivers of Virginia deserve the right to the important safety benefits that SWS delivers. Please sign this petition and help repeal this ban and give drivers in Virginia the freedom to use their property legally: http://www.thepetitionsite.com/1/repeal-the-virginia-radar-detector-ban
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    jerrybault Jun 17, 2010 2:29 AM
    drakkonwd said "Another fact left out in the story: laser cannot be used at an angle. RADAR measures the Doppler shift & it can be used at nearly a 90 degree angle from the direction you are traveling. LIDAR measures time/distance so at a steep angle, it will read slower than you are actually traveling." drakkonwd, You know far less that you think you do. Both Radar and Lidar work on the same geometry principles and only can measure the speed in the direction of the line between the Radar/Lidar and the target vehicles (this is the radial velocity), so both can only give the speed towards or away from the signal source (the cop). If the vehicle is traveling in a direction that is at an angle theta off of the line between the radar and the vehicle the measured speed will be reduced by the factor cos(theta). So a vehicle traveling 90 degrees from then line between the radar and the vehicle will register as not moving at all. This is true for both radar and Lidars.Trust me I design military radars for a living and have been doing it for 30 years. I also can defeat/jam them with out transmitting a RF signal.
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    drakkonwd Jun 16, 2010 3:44 PM
    Another fact left out in the story: laser cannot be used at an angle. RADAR measures the Doppler shift & it can be used at nearly a 90 degree angle from the direction you are traveling. LIDAR measures time/distance so at a steep angle, it will read slower than you are actually traveling. That is why overpasses or parking in the median of an interstate as is rounds a corner are so popular strategies for LIDAR operations. If you see a lonely car parked on top of a bridge you are about to drive under, slow down now.
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    roulettepete May 23, 2010 5:06 AM
    Here in the UK we have a device called Snooper. Snooper is a laser scrambling device. When a laser is detected hitting the car, the scrambler sends back a distorted signal to the laser gun, and the laser gun registers an error but does not display a speed reading. At the same time, the Snooper sounds a warning inside the car telling the driver he has been targeted. The driver can then slow down and then turn off the Snooper allowing the cop to target the car again at the lower speed. Police are getting wise to this device so regular use in the same county can be risky, however, it is worth the risk because the new mobile camera vans can target cars from 1.5 miles. Pete. pstill@amxoffset.com
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    Regardless of why drivers speed and cops ticket, each side is using technology to increase their chances of success.


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