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:
Feb. 06, 2001
Filed:
Nov. 06, 1998
Hiroyuki Kiyanagi, Sendai, JP;
Toshiaki Suzuki, Kawasaki, JP;
Yasuhiro Shibuya, Sendai, JP;
Hiroshi Suzuki, Sendai, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
The present invention is directed to a multiplex radio transmission/receiving system. The system includes a plurality of transmission sections provided so as to correspond to a plurality of channels, and a plurality of receiving sections provided so as to correspond to the plurality of channels. Each transmission section includes a modulation section, a first frequency conversion section, a first band-pass filter, a second frequency conversion section, and a second band-pass filter. Each receiving section includes a third band-pass filter, a third frequency conversion section, a fourth band-pass filter, a fourth frequency conversion section, and a demodulation section. By selection of an optimum value for a second intermediate frequency of a transmitter and for a third intermediate frequency of a receiver, a group of transmission radio frequencies (RF) signals and a group of local frequency signals are allocated without overlap. As a result, there can be prepared one type of band-pass filter which has broad band-pass characteristics and which is common among the transmission and receiving sections disposed within the multiplex radio transceiver or among repeaters, thus allowing use of common members.