Patents Represented by Attorney, Agent or Law Firm Richard A. Sonnentag
  • Patent number: 5175749
    Abstract: An apparatus automatically corrects for DC offset in a multi-level packet-switched receiver. A reference carrier frequency is used during the receiver's idle mode to establish a DC offset exiting a discriminator (302). The DC offset is amplified by a video amplifier (315) and fed into an error amplifier (320) which generates the negative of the DC offset. The DC offset and the negative of the DC offset are input into a summing network (330) resulting in a zero DC offset exiting the video amplifier (315).
    Type: Grant
    Filed: January 25, 1991
    Date of Patent: December 29, 1992
    Assignee: Motorola, Inc.
    Inventors: David A. Ficht, Gary D. Schulz
  • Patent number: 5170392
    Abstract: A receiver 200 automatically compensates for intermodulation of an input signal. The receiver 200 is preceded by a receiver front-end 105 which is coupled to antennas 100-102 receiving the signal. The gain of the antenna path/frequency is calibrated and stored for all combinations of antenna path/frequency. When a signal is received, the receiver 200 determines the correct stored gain factor representing the antenna receiving the signal and the frequency of the signal. The gain factor is compared against a predetermined threshold, and if the gain factor is greater than the threshold, an attenuator 400 placed at the front of the receiver 200 is inserted to optimize signal intermodulation. If the gain factor less than the threshold, the attenuator 400 is bypassed to optimize the sensitivity of the receiver 200.
    Type: Grant
    Filed: January 16, 1991
    Date of Patent: December 8, 1992
    Assignee: Motorola, Inc.
    Inventor: Kenneth B. Riordan