公开(公告)号：CA1007707A

公开(公告)日：1977-03-29

申请号：CA144538

申请日：1972-06-13

Applicant: MOTOROLA INC DELAWARE

Inventor： SCHAEFFER DENNIS R ,  WRIGHT LARRY R

IPC: H03G3/34

Abstract: An impulse noise blanking circuit for decreasing the impulse noise in a receiver includes a level sensing circuit coupled to a stage in the signal path following the blanking elements, and to at least one amplifier stage in the noise amplifiers which amplify the impulse noise signals. The level sensing circuit senses the level of the on-channel and adjacent channel energy in the signal path and develops a level sensing signal. The level sensing signal is coupled to the noise amplifiers to vary the gain in accordance with the level sensing signals, thereby reducing the blanking rate and the resultant receiver degradation due to an excessive blanking rate. The level sensing circuit includes a field effect transistor amplifier stage and feedback circuitry to minimize the production of undesired intermodulation producing signals therein.