How Radar Works; How Laser Works - Escort Passportmax Owner's Manual

How Radar Works

Traffic radar, which consists of microwaves, travels in
straight lines and is easily reflected by objects such
as cars, trucks, and even guardrails and overpasses.
Radar works by directing its microwave beam down
the road. As your vehicle travels into range, the
microwave beam bounces off your car, and the radar
antenna looks for the reflections. Using the Doppler
principle, the radar equipment then calculates your
speed by comparing the frequency of the reflection
of your car to the original frequency of the beam
sent out.
Traffic radar has limitations, the most significant of
these being that it typically can monitor only one
target at a time. If there is more than one vehicle
within range, it is up to the radar operator to decide
which target is producing the strongest reflection.
Since the strength of the reflection is affected by both
the size of the vehicle and its proximity to the
antenna, it is difficult for the radar operator to
determine if the signal is from a sports car nearby or a
semi truck several hundred feet away.
Radar range also depends on the power of the radar
equipment itself. The strength of the radar unit's
beam diminishes with distance. The farther the radar
has to travel, the less energy it has for speed
detection.
Because intrusion alarms and motion sensors often
operate on the same frequency as X and K band
radar, your detector will occasionally receive non-
police radar signals. Since these X band transmitters
are usually contained inside of a building or aimed
toward the ground, they will generally produce much
weaker readings than will a true radar encounter. As
you become familiar with the sources
of these pseudo alarms in your daily
driving, they will serve as
confirmation that the device's radar
detection abilities are fully
operational.
How POP Works
POP works by transmitting an extremely short burst,
within the allocated band, to identify speeding
vehicles in traffic. Once the target is identified, or
"popped," the gun is then turned to its normal
operating mode to provide a vehicle tracking history
(required by law).
NOTE: According to radar gun manufacturers, tickets
should not be issued in pop mode.

How Laser Works

Laser speed detection is actually light detection and
ranging (LIDAR). Laser guns project a beam of
invisible infrared light. The signal is a series of very
short infrared light energy pulses that move in a
straight line, reflecting off your car and returning to
the gun. Laser uses these light pulses to measure
the distance to a vehicle. Speed is then calculated by
measuring how quickly these pulses are reflected,
given the known speed of light.
Laser is a newer technology whose use is not as
widespread as conventional radar; therefore, you may
not encounter it on a daily basis. And unlike radar
detection, laser is not prone to false alarms. Because
laser transmits a much narrower beam than does
radar, it is much more accurate in its ability to
distinguish between targets and is also more difficult
to detect. As a result, even the briefest laser alert
should be taken seriously.
There are limitations to laser, however. Laser is much
more sensitive to weather conditions than radar,
and a laser gun's range will be decreased by anything
affecting visibility, such as rain, fog or smoke. A
laser gun cannot operate through glass, and it must
be stationary to get an accurate reading. Because
laser must have a clear line of sight and is subject to
cosine error (an inaccuracy that increases as the
angle between the gun and the vehicle increases),
police typically use laser equipment parallel to the
road or from an overpass. Laser can be used day or
night.
How TSR Works
PASSPORT Max includes a new boost in anti-falsing
software to eliminate excessive alerts from
erroneous X and K band sources, such as traffic flow
monitoring systems. These systems, which are
becoming more widely used in several countries,
generate K band signals to measure the flow of traffic
on a given road. Unfortunately, most detectors see
this as a real threat and will alert you to it
unnecessarily. Our new proprietary software,
TSR, intelligently sorts, ranks and rejects
these types of false alarms automatically. The result is
ultimate protection without excessive false alarms.