Local oscillator null circuit and method

Details Local oscillator null circuit and method Local oscillator null circuit and method

1985-04-25

1987-03-31

Ng, Jin F.

Telecommunications

Receiver or analog modulated signal frequency converter

Frequency modifying or conversion

455319, 455325, H04B 126, H04B 110

Patent

active

046548866

ABSTRACT:
A local oscillator null circuit and method for use in tuning a wideband, heterodyne receiver relatively close to zero frequency without experiencing excessive feedthrough from a local oscillator to an associated IF stage in the receiver. The local oscillator is connected to circuit means for generating a derivative signal proportional to the local oscillator signal and shifted in phase with respect thereto by a desired amount determined by the phase difference between the local oscillator signal and the signal in the mixer output spectrum which is at the local oscillator frequency. The null circuit combines the derivative signal with the mixer output signal proportionally to produce a null at the local oscillator frequency.

REFERENCES:
patent: 3781722 (1973-12-01), Pierson
patent: 4325023 (1982-04-01), Zirwick
patent: 4355420 (1982-10-01), Ishihara
patent: 4451782 (1984-05-01), Ashida

Affiliated with

Also associated with

Rating

Local oscillator null circuit and method does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Local oscillator null circuit and method, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Local oscillator null circuit and method will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2218484