What is the frequency shift for X-Band at a speed of 1 mph?

• A. 25.4
• B. 31.4
• C. 45.7
• D. 50.2

Answer: (B)

The correct choice for the frequency shift of X-Band radar at a speed of 1 mph is determined by the Doppler effect formula. The frequency shift is calculated based on the speed of the target relative to the speed of the radar wave. In this case, X-Band radar typically operates at a frequency of 10.525 GHz.

To calculate the frequency shift, the formula used is:

Frequency Shift (in Hz) = (2 * Speed of the target in mph * Frequency in GHz * 5280) / 3600

When you plug in the given values, the frequency shift results in approximately 31.4 Hz for a target moving at 1 mph. This value reflects how much the frequency of the emitted radar signal changes due to the relative motion between the radar and the vehicle.

Understanding this concept is crucial for interpreting radar readings and understanding speed measurements in law enforcement contexts. The frequency shift increases as the speed of the target increases, which can be essential information when calculating speeds accurately and recognizing how distance and movement affect radar signals.