Patent ID: 6693578
Filing Date: 2004-02-17
Classification: G01S,H03D,H03J

Abstract:
A mixer optimization method for a radar warning receiver having an antenna adapted to receive police radar signals in the X, K and Ka bands, a variable power local oscillator adapted to output a local oscillator signal, and a current-biased mixer coupled to output IF signals at an IF frequency correlated to respective harmonics of the local oscillator signal associated with the respective police radar signal bands, the mixer optimization method comprising:operating the local oscillator to output a local oscillator signal at a frequency associated with a sweep of the X band, biasing the mixer with a first predetermined current correlated to the X band, monitoring a DC voltage of the mixer, adjusting the power of the local oscillator until the DC voltage of the mixer is at a first predetermined voltage, and thereafter, with the power of the local oscillator set to the power as so-adjusted, operating the receiver to output IF signals at a frequency correlated to a first respective harmonic of the local oscillator signal associated with the X band; operating the local oscillator to output a local oscillator signal at a frequency associated with a sweep of the K band, biasing the mixer with a second predetermined current correlated to the K band, monitoring a DC voltage of the mixer, adjusting the power of the local oscillator until the DC voltage of the mixer is at a second predetermined voltage, and thereafter, with the power of the local oscillator set to the power as so-adjusted, operating the receiver to output IF signals at a frequency correlated to a second respective harmonic of the local oscillator signal associated with the K band; and operating the local oscillator to output a local oscillator signal at a frequency associated with a sweep of the Ka band, biasing the mixer with a third predetermined current correlated to the Ka band, monitoring a DC voltage of the mixer, adjusting the power of the local oscillator until the DC voltage of the mixer is at a third predetermined voltage, and thereafter, with the power of the local oscillator set to the power as so-adjusted, operating the receiver to output IF signals at a frequency correlated to a third respective harmonic of the local oscillator signal associated with the Ka band.