Receiver interference suppression system

DETAILED DESCRIPTION Accordingly, it is an object of the present invention to provide an improved radio receiver which utilizes a simple, effective, and inexpensive solution to the problem of distinguishing a desired signal from a strong interfering signal at a frequency nearly the same as the frequency of the desired signal.
Another object of the present invention concerns providing an improved interference suppression system which may be adapted only to a receiver portion of a radio.
Yet another object of the present invention concerns providing an improved interference suppression system which may augment interference suppression achieved through conventional techniques, such as the use of highly selective IF filters.
Still another object of the present invention concerns providing an improved interference suppression system through coherent differencing of equal amplitude limited and linearly amplified portions of a received signal.
The above and other objects and advantages of the present invention are carried out in one form by a receiver interference suppression system which includes a limiter, a gain controlled amplifier, and a subtractor.
A received signal is applied to inputs of both the limiter and gain controlled amplifier.
The amplitudes of a signal output from the limiter and a signal output from the gain controlled amplifier are adjusted to be approximately equal.
In addition, both the limiter and the gain controlled amplifier produce substantially constant amplitude signals over time.
The output of the limiter and the output of gain controlled amplifier couple to unique inputs of the subtractor.