EP0225607A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Portable radio telephone system
Assignee: Hitachi Ltd
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Filing: 1986-12-04
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Granted: —
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Expires: 2006-12-04
Abstract
Abstract In order to make it possible to communicate between a portable radio telephone set through an existing public cellular radio telephone system and a private radio telephone system disposed inside the cells of the public cellular radio telephone system, an antenna and a transceiver for connecting the antenna to the private radio telephone system are disposed in each cell, and the transmitting power from the antenna and the transmitting power from the portable telephone set are set so that they do not impart interference waves to the public cellular radio telephone system.
Inventors
- 👤 Yasuaki Kinoshita
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-27 05:05
CPC Classifications
H; H04; H04W; H04W16/00; H04W16/14; H04W16/02; H04W16/12
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
175 words
In a portable radio telephone system of the type wherein a given area is divided into a plurality of large areas, each of said large areas is further divide into a plurality of small cellular areas, the same radio frequency channel can be reused between said large areas, radio frequency channels different from one another are allowcated to said small cellular areas of said large area and radio communication is made by a telephone set by use of the allocated frequency channels; a portable radio telephone system characterized in that a local area is disposed inside at least a part of said small cellular areas, said system consists of antennas for transmitting and receiving radio waves, said telephone sets, a private branch exchange and a transmission/ reception circuit connecting said antennas to said private exchange, and radio communication is also made inside said local area by said portable telephone set by reuse of said radio waves of frequency channels different from said channels allocated to said small cellular area to which said local area belongs.
Claim 2
Dependent Claim
175 words
In a portable radio telephone system of the type wherein a given area is divided into a plurality of large areas, each of said large areas is further divide into a plurality of small cellular areas, the same radio frequency channel can be reused between said large areas, radio frequency channels different from one another are allowcated to said small cellular areas of said large area and radio communication is made by a telephone set by use of the allocated frequency channels; a portable radio telephone system characterized in that a local area is disposed inside at least a part of said small cellular areas, said system consists of antennas for transmitting and receiving radio waves, said telephone sets, a private branch exchange and a transmission/ reception circuit connecting said antennas to said private exchange, and radio communication is also made inside said local area by said portable telephone set by reuse of said radio waves of frequency channels different from said channels allocated to said small cellular area to which said local area belongs.
Claim 3
Dependent Claim
18 words
A portable radio telephone system according to claim 1, wherein said local area lies in a building structure.
Claim 4
Dependent Claim
48 words
A portable radio telephone system according to claim 2, wherein a plurality of antennas is disposed-inside said building structure and frequency channels different from said frequency channels allowcated to said small cellular area to which said local area belongs are used for radio communication inside said building structure.
Claim 5
Dependent Claim
49 words
A portable radio telephone system according to claim 2, wherein said local area disposed in one of said small cellular areas consists of a plurality of mini areas, and said antennas disposed in said mini areas adjacent to one another transmit and receive radio waves of mutually different frequencies.
Claim 6
Dependent Claim
126 words
In a portable telephone set according to claim 1 having an antenna, a receiver for receiving a signal from said antenna, a transmitter for transmitting a transmission signal to said antenna, a frequency synthesizer for determing the operation frequency of each of said transmitter and and said receiver, a transmitting power controller for controlling the transmitting power of said transmitter, a transmission/reception handset and a control part for sending controlling signals to said frequency synthesizer and to said transmitting power controller, a portable telephone set characterized in that said control part has switch means for communication using first frequency channels allocated to small cellular areas and second frequency channels different from said first frequency channels used in small cellular area to which said local area belongs.
Claim 7
Dependent Claim
49 words
A portable telephone set according to claim 5, wherein said transmitting power controller has switch means for switching a first power level necessary for communication using said first frequency channels and a second power level of transmitting power having said second frequency channels different from said first frequency channels.
References Cited (Backward Citations)
No citation records indexed.
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