RADAR STUDY GUIDE
Antenna and alignments, are their advantages and disadvantages to the officer and/or the
violator? - ANS-Antennas should be aligned straight ahead to reduce cosine effect. Any
other positioning would have a significant effect on the speed displayed, favoring the violator
Are there any devices in a patrol vehicle that can cause improper readings for a RADAR unit
or LIDAR unit? - ANS-The motion of fans, rotating wheels, and windshield wipers can affect
RADAR, but LIDAR will not be.
Batching effects - ANS-"Target Speed Bumping" - May cause high or low targe speeds due
to inability to maintain a current patrol vehicle speed. Usually caused by sudden changes in
patrol speed such as accelerating or braking "processor has a hard time telling what the
heck you're doing"
Define wave frequency - ANS-The number of waves that pass a fixed point in a given
amount of time (HIGH FREQUENCY - 7 WAVES IN PERIOD) (LOW FREQUENCY - 3
WAVES IN PERIOD)
Does LIDAR and the cosine effect have any bearing on suspected target vehicle? -
ANS-Cosine effect will ALWAYS be in favor of the violator, and should be considered when
conducting speed enforcement
Doppler principle - ANS-When energy (light, radio, or sound) is transmitted & is reflected by
or from a moving object its frequency will change in direct proportion to the speed. Moving
closer = increased frequency
How accurate is a RADAR device? - ANS-Accurate under optimal conditions but can be
affected by many things including spurious readings, targets, and weather conditions
How can a Laser speed measurement device be used? - ANS-Similar to RADAR but with
target acquisition, and can only be used in stationary mode
How does a radar work to calculate moving vehicles in the oncoming lane? - ANS-Target
Speed = Closing speed - Patrol speed
How is RADAR on target vehicles on curves? - ANS-Causes cosine effect due to not being
parallel > favors the violator
("It's not good")
How should an officer use a LIDAR? - ANS-Automatic self-Test (done when turned on);
Conduct a optics alignment test, Display test, Accuracy test (delta distance).
Stationary Mode Only, used parallel to motion of traffic
If the violator contests a ticket and there is heavy traffic. Is it plausible for the officer to say in
court that "the reflected signal will always be the closest vehicle in the antenna." - ANS-No,
sensitivity of the RADAR signal is affected by:
1. Target Size
2. Target Speed
3. Target Shape
4. Target composition
5. Target Position
If you extend the range on a radar device what may happen? - ANS-Increased radar
sensitivity may hinder target acquisition and cause more spurious readings
Antenna and alignments, are their advantages and disadvantages to the officer and/or the
violator? - ANS-Antennas should be aligned straight ahead to reduce cosine effect. Any
other positioning would have a significant effect on the speed displayed, favoring the violator
Are there any devices in a patrol vehicle that can cause improper readings for a RADAR unit
or LIDAR unit? - ANS-The motion of fans, rotating wheels, and windshield wipers can affect
RADAR, but LIDAR will not be.
Batching effects - ANS-"Target Speed Bumping" - May cause high or low targe speeds due
to inability to maintain a current patrol vehicle speed. Usually caused by sudden changes in
patrol speed such as accelerating or braking "processor has a hard time telling what the
heck you're doing"
Define wave frequency - ANS-The number of waves that pass a fixed point in a given
amount of time (HIGH FREQUENCY - 7 WAVES IN PERIOD) (LOW FREQUENCY - 3
WAVES IN PERIOD)
Does LIDAR and the cosine effect have any bearing on suspected target vehicle? -
ANS-Cosine effect will ALWAYS be in favor of the violator, and should be considered when
conducting speed enforcement
Doppler principle - ANS-When energy (light, radio, or sound) is transmitted & is reflected by
or from a moving object its frequency will change in direct proportion to the speed. Moving
closer = increased frequency
How accurate is a RADAR device? - ANS-Accurate under optimal conditions but can be
affected by many things including spurious readings, targets, and weather conditions
How can a Laser speed measurement device be used? - ANS-Similar to RADAR but with
target acquisition, and can only be used in stationary mode
How does a radar work to calculate moving vehicles in the oncoming lane? - ANS-Target
Speed = Closing speed - Patrol speed
How is RADAR on target vehicles on curves? - ANS-Causes cosine effect due to not being
parallel > favors the violator
("It's not good")
How should an officer use a LIDAR? - ANS-Automatic self-Test (done when turned on);
Conduct a optics alignment test, Display test, Accuracy test (delta distance).
Stationary Mode Only, used parallel to motion of traffic
If the violator contests a ticket and there is heavy traffic. Is it plausible for the officer to say in
court that "the reflected signal will always be the closest vehicle in the antenna." - ANS-No,
sensitivity of the RADAR signal is affected by:
1. Target Size
2. Target Speed
3. Target Shape
4. Target composition
5. Target Position
If you extend the range on a radar device what may happen? - ANS-Increased radar
sensitivity may hinder target acquisition and cause more spurious readings
