The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 03, 1986
Filed:
Sep. 26, 1985
Takayuki Ozaki, Tochigi, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
A space-diversity receiving system for microwave band radio communication including two antennas and receivers, an endless phase shifter, a hybrid combiner, a hybrid distributor, a voltage controlled oscillator, a signal mixer, a low pass filter, a detector, and a control circuit. Microwaves received by the antennas are detected by the receivers. One received signal is directly applied to the hybrid combiner. The other received signal is applied to the hybrid combiner via the endless phase shifter. The hybrid combiner combines these signals and outputs to the hybrid distributor. The hybrid distributor distributes the amplified output to as an intermediate frequency output and a sub output. The voltage controlled oscillator generates a series of sequential frequencies based on the control of its input voltage. The signal mixer mixes the sub output with the each sequential frequency output. The detector detects the mixed signal and transmits the detected signal to the control circuit. The control circuit controls the endless phase shifter and the voltage controlled oscillator based on the deviation in the intermediate frequency band and the detection of the reception level so as to minimize the amplitude deviation of the combined IF output signal by using a microprocessor.