Q - What is Doppler Radar?

A - Stalker Speed Sensor Radar uses the Doppler frequency shift technique to measure the speed of moving objects. This technique is based on the Doppler Theory, which states that a radar signal reflected from a moving target will experience a frequency shift that is proportional to the speed of the target relative to the radar. Circuitry in the Stalker Speed Sensor Radar then processes the reflected signal to obtain the frequency shift and translate this frequency shift into speed.

Q - How is speed data displayed and what type of physical data interface is used?

A - To hold unit cost to a minimum the speed sensor is not a complete radar system and does not actually display the speeds. The speed sensor is an OEM product to be integrated into your own equipment by your design engineer. However, for maximum flexibility the Stalker Speed Sensor communicates via a variety of data protocols which we supply to you.

Q - What is the Operating Frequency?

A - 34.7GHz (Ka-Band).

Q - What are the Power Requirements?

A - 9 - 16 VDC; 370 mA at 12 VDC, transmitter on; 100 mA at 12 VDC, transmitter off.

Q - What are the Environmental Requirements?

A - Operating: -30C to +70C, 90% relative humidity; Non-operating: -40C to +85C.

Q - What are the Mechanical Dimensions?

A - Weight - 1.15 lb. (0.52 kg); Diameter - 2.6 in. (6.7 cm); Length - 4.7 in. (11.8 cm).

Q - What is the Speed Measurement Accuracy?

A - +1, -2 MPH stationary; +2, -3 MPH moving (if applicable); +1, -2 KPH stationary; +2, -3 KPH moving (if applicable).

Q - What is Cosine Error?

A - The most common mistake made with all radars is trying to clock targets at angles. All radars should clock objects moving directly at or away from the radar. Clocking at an angle with a stationary radar will result in angle error, and the radar will display a speed that is LOWER than the actual speed. In order to get accurate readings, the radar must be placed in the line of travel of the target. At slight angles, the error will be very small, however at larger angles, the error will be substantial. If you know the angle, you can calculate the actual speed by taking the radar reading and dividing by the cosine of the angle. For example: if your angle is 30 degrees and the radar reads 129.9 mph. Take 129.9 and divide by the cosine of 30 degrees (0.866) to get a true speed of 150.0 mph.