Patents Examined by Mark Hellnes
  • Patent number: 4638319
    Abstract: A bearing indicating R.F. system comprising two spaced, broad-beam antennas supplying signals via power dividers to amplitude comparison means and phase comparison means, both operating without down-conversion to I.F. The main lobes of the radiation patterns of the antennas are inclined towards one another so that for non-normal incidence there is a difference between the amplitudes of signals received by the antennas. The amplitude comparison means comprises detector diodes, logarithmic amplifiers, and a first subtractor, the magnitude of the output signal (sensed with a threshold detector indicating which side of normal the radiation is incident. The phase comparison means comprises a hybrid ring having "sum" and "difference" output ports connected to an instantaneous frequency measuring apparatus and a detector diode, and further comprising logarithmic amplifiers and a second subtractor, the outputs of detector diodes in IFM being summed to provide a signal output connected to one amplifier.
    Type: Grant
    Filed: June 15, 1984
    Date of Patent: January 20, 1987
    Assignee: U.S. Philips Corporation
    Inventor: Lye-Whatt Chua