Everything you need to know about police radar, laser and speed cameras in Tasmania

1) What are the different types of police radar / laser & speed cameras used in Tas?

a) What is the respective the tolerance / accuracy of each device?

 

b) What are the guidelines for use of this equipment?

 

c) How do these devices make mistakes?

i) Moving Radar errors and mistakes

 

ii) Laser (LIDAR) errors and mistakes

 

iii) Speed camera errors and mistakes

2) What products offer the best protection against these types of police radar / laser / cameras?

a) What are the laws governing the use of radar / laser detectors in Tas?

 

b) Can the police determine if you are using a radar detector?

3) What are the penalties / demerit points and speeding fines for Tas?

a) If I know I wasn't speeding, how can I challenge / beat a speeding fine

4) What are the road fatality statistics for Tasmania?

5) Summary for police radar, laser and speed cameras in Tasmania

What Radar / Laser speed measuring devices are used in Tasmania?

Firstly, it needs to be explained that there are four different RADAR bands (frequencies) used throughout the world as well as LASER (which is completely different to radar).

The four radar bands include:

X-Band (10.275GHz up to 10.775GHz) - not used anywhere in Australia

K-Band (24.050GHz up to 24.250GHz)

Ka-Band (33.400GHz up to 36.000GHz) - Australia is licensed for 34.2 - 35.2GHz only

Ku-Band (13.175GHz to 13.675GHz) - not used anywhere in Australia

Radar (short for radio and ranging) works by transmitting a pulse of electromagnetic (EM) energy, also referred to as RF energy at a moving object.  Using the Doppler principle the radar gun ‘listens’ to the change in pitch of the radio waves as they reflect off the moving vehicle and thus determines the speed.  Similarly when a train blows its whistle as it passes you – you can hear the change in pitch of the whistle, as the train moves past. 

The radar beam starts out as a small diameter pulse when it leaves the radar gun, but grows quite rapidly as the distance increases from the gun.  At a distance of 300 metres, the radar beam is now 100 metres tall and 200 metres wide! If 6 cars were simultaneously hit by a radar beam (six vehicles driving down the freeway), 6 pulses would come back to the radar gun, and the radar gun would detect (and report the speed of) the largest signal of the 6 signals present.  To overcome this shortfall, the latest radar units with Digital Signal Processing (DSP) can identify the strongest and the fastest targets to try and help the police officer identify which vehicle's speed is being displayed on the radar gun.

Because the radar beam is so large when traveling down the road, a radar detector can be located almost anywhere in or on the vehicle, and it will detect the radar signal.  Radar will penetrate glass, plastic, even people, but is reflected by metal and metallic objects.  Radio waves will only travel in a straight line, so you are relying on reflections of other objects to give you advanced warning if you do not have a line of site with the radar gun.

Traffic radar uses a radar beam to measure speed. Think of the beam as a searchlight. It’s invisible because it’s made of microwaves instead of light, but otherwise it acts very much like a light beam. It travels in straight lines. It’s easily reflected. It scatters as it is passed through dust and moisture in the air. And — this is essential — it has to hit your car before it can determine your speed. Radar can’t see around corners or through hills. It can’t see you when you are behind another vehicle. When in the clear, how strongly your vehicle reflects determines at what distance the radar can detect your speed. Generally, larger vehicles reflect more strongly than smaller vehicles. Trucks are more “visible” at further distances than cars. The principle on which radar operates is absolutely reliable. Radar equipment, on the other hand, is only as good as the quality of its design and manufacture. Traffic radars tend to be unreliable. They’re cheaply made and therefore vulnerable to many interferences that cause false readings. And, compared to the military and weather radar which have rotating antennas, traffic radars are vastly simplified. This simplification means that traffic radar cannot tell one car from another. The operator has to do that, and since the operator can’t see an invisible beam any better than you can, he frequently doesn’t know which vehicle’s speed is being read. This is a source of many undeserved tickets.

As a defense against radar detectors, many police radar units can be operated in the Instant-on mode, also called the Pulse mode. This means the radar is in position, but it is not transmitting a beam. So it cannot be detected. When the target is within range, the radar operator switches on the beam and the radar calculates the speed, usually in less than a second. This calculation happens too quickly for the target (you) to respond in time.  Still, you can defend against Instant-on by recognizing it when the operator zaps traffic ahead of you.

As well as radar, there is also LASER (also known as LIDAR, - LIght Detection And Ranging), which operates at a frequency of 904nm ± 33MHz. A police laser (LIDAR) gun emits a highly focused beam of invisible light, in the near infrared region of light, at 904nm of wavelength, with the beam being around 50cm in diameter at a distance of 300m from the laser gun. Unlike RADAR which determines a vehicle's speed by measuring its Doppler shift, police laser (lidar) calculates speed by observing the changing amount of time is takes to "see" reflected pulses of light over a discreet amount of time.

Because the laser beam's diameter is so narrow, if a laser gun is aimed at the license plate, the beam is so small, that most times, none of the laser signal would actually “spill over” up to the windshield, where your detector is mounted.  Thus, a radar detector with laser detector mounted on the windscreen would not even detect the laser beam targeted on the license plate (or headlights or bumper for that matter). This means the beam of a laser gun is accurate enough to target a single vehicle out of, let’s say, six vehicles driving down the freeway. The laser gun can target and detect that single vehicle in less than ½ second after the trigger is pulled, while the surrounding vehicles would not detect the laser beam as it passed right beside their vehicle! 

Other than radar and laser, there are other ways of calculating a vehicle's speed being:

• Vascar - This is not a radar or laser, system; rather it is a glorified stopwatch that relies on the policeman's honesty and accuracy. They are mounted in the police car and are often used when following the target. When the target car goes past a landmark (usually a white marking across the road), the timer is started and when the car goes past the second landmark, the timer is stopped. It is hooked up to the patrol car's speedometer to give a target speed reading. It relies on the button being pushed at the right time and the pacing distance to be long enough to overcome any timing errors. The only countermeasure is careful observation, or a GPS unit if it's a regularly used Vascar area.

• Piezo-electric strips - pressure-sensitive strips embedded in the roadway (a set distance apart if speed is to be measured - typically 1-3 metres).

• Inductive Loops - embedded in the roadway detect the presence of vehicles, and with two loops a set distance apart vehicle speed can be measured.

• Arial Speed checks (similar to Vascar)

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In Tasmania, the police use the following speed measurement devices:

Dash Mounted radar (aka moving radar) set up in police cars:

The first dash-mounted radars used in Tas were the KR10-SP manufactured by Kustom Signals Inc in the USA.  These units can be used in stationary and moving mode, and can be used in "instant on" mode or "constant on" mode.  One antenna for front only or two antennas for front / rear.

Hand-held laser (aka lidar):

Speed Cameras:

The first speed camera used in Tasmania were the tripod mounted AWA slant radars.  The AWA Slant radar requires a minimum of three officers to operate effectively. For an optimum level of safety, however, four to five personnel are required. This places a heavy burden on human resources, particularly if it is operated over a number of sites during one day.  POLTECH International Limited (POLTECH) listed on the Australian Stock Exchange (PLL) in July 1998.  It has since gone into receivership leaving many failing cameras in their wake.  It is thought Tasmania has replaced the Poltech cameras with the Redflex cameras.

How accurate are these devices?

The assumption being made here, is that the speed measuring equipment is being used according to the manufacturer's guidelines (see below).

Speed Laser (Lidar) mistakes

Police LIDAR can also make errors if not operated according to the manufacturer's guidelines.

 

1. Stationary - Laser cannot be used in moving mode, they must be used whilst stationary.  Similar to radar, laser cannot be used in the rain, snow, or high dust environments.

 

2. Interference - If for any reasons intended signal returns are interrupted, it may not be able to determine target velocity. Bright lights (such as Halogens) beaming directly into a laser aperture may desensitize or entirely masks target's echoes. The brighter and closer the light source the greater the chance of interference.

 

3. Cosine Error - Is the angle from 0* perpendicular to the target vehicle. The greater the cosine angle the greater the error. However, cosine error is always in favor of the motorist, one of the speed readings will be will be proportionally less than the actual speed of the target vehicle.

 

4. Sweep Error (also known as pan or slip error) - Is manifested when the laser is aimed at one part of the vehicle, say the license plate, and due to the motion of the operator, the laser also targets a side mirror during the same trigger pull. Sweep Error adds to the real speed of the target vehicle. See videos below.

 

5. Reflection Error - On very hot days with low humidity a visible mirage/reflection of the target vehicle is created. In many cases, when the laser is aimed at the target vehicle the infrared beam also receives readings from both the target vehicle and the mirage causing a Sweep Error.

 

6. Overexposure Error - When a laser gun receives an extremely powerful reflective signal, such as a sun flare off a vehicle, the computer's timer can't see return of the 904 nanometer signal it sent. It can't compute a speed reading. In general, the laser gun is looking for the strongest return reflection of its own emitted beam for speed computation.

 

LTI 20.20 exposed as unreliable (source)

Daily Mail, 15th October 2005.

 

In tests the speed gun recorded a wall speeding at 44mph. (Yes, a brick wall, that's not a misprint) Other tests showed a bicycle doing 66mph and a parked car doing 22mph. The Daily Mail reports that even when the camera is set up following the police's own guidelines and the manufacturer's handbook some of the readings were wildly off the mark.

 

Another discovery, writes The Daily Mail, is that vital video film, often taken as secondary evidence, is often mysteriously withheld from accused motorists by the CPS. On at least 10 occasions the CPS has suddenly dropped the case against a motorist when ordered by a judge to hand over the revealing footage. 

 

Dr Michael Clark is Europe's leading expert on laser technology and a former directory of a company making laser detection equipment for traffic lights and car parks. He's also a fierce critic of the speed gun and has acted as an expert witness on behalf of many motorists since he defended himself after being caught for alleged speeding.

 

Dr Clark says the gun is defective because its wide beam can easily pick up the wrong vehicle and if not held firmly on the target (which is a difficult task itself) it can produce an erroneous speed result because of "slippage".

 

Reflections from road signs and from other cars, even stationary ones, can also make the laser device misinterpret the true speed of the vehicle. The LTI 20.20 works by sending out a beam to measure the distance of the target from the officer operating it and also how long it takes for the beam to reflect off the target and bounce back. The operator looks through the sights and sees a red dot which he aims onto the target and presses a trigger. Critically the beam must be held firmly at the same point on the moving vehicle. But if slippage occurs and the beam moves up, down, or along the vehicle the gun will measure an inaccurate reading.

 

In tests in the USA it was shown that if the beam slips from the windscreen of a car down to its grille on the bonnet it can add 8mph onto the vehicle's measured speed. If it slips along the length of the car - which is possible when a vehicle comes around a corner into the speed gun's sights - a whopping 30mph can be added on to the reading.

 

The BBC's experiments with the LTI 20.20 were dismissed by both the UK importers and ACPO (Association of Chief Police Officers) saying it was impossible for the gun to make any errors and that the BBC used an American version of the gun which they claim has less reliable software.

 

However, that claim was been rejected by the Daily Mail who obtained a UK version of the gun - a LTI 20.20 Ultralyte certified by Tele-Traffic, the UK importers based in Warwick.

 

Dr Clark points out during the experiments that the gun uses a multi-mode laser which uses 3 beams, not one. Over a long distance the beams widen so if it's targeted onto one vehicle it can unintentionally hit another vehicle nearby by mistake. Dr Clark said "A policeman can't tell from 400 meters away - or even at a longer distance in many cases - exactly which car he is marking." To demonstrate his point they parked a car at the side of the road and drove a white van past it at just 3mph. The laser gun was pointed at the car from 371 meters away which, according to the handbook, is easily within its capabilities.

 

Another problem is reflection from other vehicles. They pointed the gun at a different parked car and slowly drove the white van past. It recorded the parked car doing 22mph. Dr Clark explains "The beam sometimes catches the reflection of a nearby car. It zig-zags to this car before carrying on to the target vehicle and returns by the same route."

 

In their final experiment they pointed the gun at a brick wall with no moving vehicles in the area. They moved the beam along the wall instead of keeping it perfectly still on a single point to create the slippage effect. The gun was confused and showed a speed of 44mph. Dr Clark said "This shows how a traffic officer can mistakenly pick up a reading from a wall by the side of a motorway or even an empty road if he doesn't target a vehicle properly. Of course there's no record to prove if an officer had targeting the vehicle properly or not. Assumption of accuracy is always taken for granted even if the officer had unwittingly made a mistake.

 

ACPO state that the gun shouldn't be used at distances more than 500 meters, but Dr Clark says that it's being used in some cases at double that distance.

 

Despite the recent media interest in these issue the shortcomings of the gun was discovered nearly a decade ago in 1996 in the US state of New Jersey. The state temporarily banned the gun after a court witnessed someone targeting the gun on a wall of the courtroom and it measured 4mph. The lawyer, Joe Maccarone, defending a motorist accused of speeding called on an expert from NASA. The expert said that at just over 300 metres there was only a 60% chance of a human operator hitting a 12 foot wide target with a laser gun. Cars are only 6 foot wide so the chances of hitting something other than the target are very high indeed.

 

 

Hand-held laser mistakes videos

If you have been given a ticket from a laser gun when you were positive you weren't doing the alleged speed, then

YOU MUST WATCH THIS VIDEO!

 

A pop-up window will appear so please make sure your pop-up blocker doesn't prevent it from opening and playing in a new window.

 

 

Part Two

This video also shows how "reflection" can also create errors in speed readings, as well as the slip error as featured in the first video

 

A pop-up window will appear so please make sure your pop-up blocker doesn't prevent it from opening and playing in a new window.

 

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Speed camera mistakes:

 

The police and the government would like to have us believe in their "utmost confidence in the accuracy of speed cameras".  Of course they would, as a proven fault could cost them millions of dollars in repaid fines and loss of revenue, not to mention a loss of confidence.  Victoria was the first state to set a precedence with the Government having to repay 26 million dollars in unjust fines from faulty speed cameras.

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What is the best defense against each of these speed measuring devices??

The ultimate defense against laser is by the use of an active laser jammer.  Unlike most active radar jammers, active laser jammers do work.  An active laser jammer will prevent a speed being displayed for a brief time whilst you adjust your speed if necessary.  The best laser jammers for the LTI Ultralyte according to the Guys Of Lidar 2007 test is the Laser Interceptor.

Fixed Speed Cameras:

The best product for alerting to a fixed red light camera is a GPS device that stores these locations in a database.  Many GPS manufacturers offer products that add this service (called "point of interest") to their navigation products.  A GPS based device is perfectly legal to own and operate in Tasmania at the time of writing.

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