Patent ID: 9075144
Filing Date: 2015-07-07
Classification: G01S

Abstract:
1. A method for determining a height above ground of an aircraft, the method comprising the steps of: generating, using a local oscillator linear sweep generator, a local oscillator signal that is swept over a frequency range; generating, using a transmitter linear sweep generator, a transmit signal with a transmitter that is swept over the frequency range and delayed in time with respect to the local oscillator signal; transmitting the transmit signal with a first antenna; receiving a receive signal with a second antenna; mixing, using a mixer, the receive signal with the local oscillator signal to generate a baseband signal having a frequency of interest for calculating an aircraft altitude; adjusting, using a controller, the delay in time while the aircraft is on the ground until the frequency of interest is at least equal to a minimum difference frequency; and calculating, using the controller, the aircraft altitude based on the frequency of interest determined from the receive signal and the local oscillator signal.