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:
Apr. 15, 1997
Filed:
Aug. 23, 1994
ADC Telecomminications, Inc., Bloomington, MN (US);
Abstract
A passive handoff cellular communication system includes a cell divided into a plurality of zones. A base station is connected by transmission apparatus to a plurality of antenna units. The base station includes analog RF signal generation circuitry for generating a plurality of RF signals on different channels and a first switch responsive to a first control signal for switching and combining the RF signals to form a composite RF signal for each zone. Analog-to-digital conversion circuitry converts the composite signal for each zone to a digitized stream of samples and applies the samples to the transmission apparatus for transmission to each corresponding antenna unit. Each antenna unit includes digital-to-analog conversion circuitry for receiving the digitized stream of samples from the base station, reconstructing a corresponding composite analog RF signal, and applying an amplified signal to the antenna The base stations further include a second switch and combining means responsive to a second control signal for selectively combining the RF signals from the antenna units to form a plurality of composite signals for application to the receivers of the base station. A controller monitors the digitized streams of samples from all of the antenna units, digitally analyzes the energy level of each channel in each zone, and generates the first and second control signals to selectively control the zones in which each channel is broadcast and the zone from which each channel is received.