Radio network with switching arrangement for coupling radios to a selected antenna out of a plurality of antennas

• US 5,175,878 A
• Filed: 02/02/1990
• Issued: 12/29/1992
• Est. Priority Date: 02/02/1990
• Status: Expired due to Term

• Current Assignee: American Telephone & Telegraph Company (AT&T, Inc.)
• Original Assignee: AT&T, Inc.
• Inventors: Reed, George M., Davis, Bernard P.
• Primary Examiner(s): Eisenzopf, Reinhard J.
• Assistant Examiner(s): Pham, Chi H.
• Application Number:
  US07/474,562
• Time in Patent Office: 1,061 Days
• Field of Search: 455/129, 455/132, 455/133, 455/136-138, 455/160, 455/272, 455/273, 455/103, 455/101, 455/277, 455/281, 455/282, 333/100, 333/101, 333/103, 333/106, 340/825.02, 340/825.03, 340/826
• US Class Current: 455/103
• CPC Class Codes: H01Q 3/24 varying the orientation by switching energy from one active radiating element to another, e.g. for beam switching

Abstract

The antennas of a cellular telephone system are each connected to a signal divider/combiner array which/divides combines the antenna connecting path(s) into a plurality of antenna-radio/radio-antenna connecting paths. The divider array aspect is used for signal reception and the combiner array aspect is used for signal transmission. Each of these antenna connecting paths is connected to a controllable switch which in turn selectively couples it to/from a second plurality of radio transceivers. The antenna transmission/receive paths comprising the signal divider/combiners are embodied as strip type transmission lines in a multi layer PCB with all the paths having equal transmission losses. Micro vias are provided to permit electrical access to the various layers. The controllable switches are surface mounted on the outside of the PCB and are coupled to the various dividers/combiner through the micro vias. Remote control of the switches permits a radio channel unit of transceiver to be connected to any one of the array of antennas.

Claims

1. In a cellular radiotelephone system a radio antenna interconnection arrangement for enabling connection of a plurality of radio transceivers to selected ones of a plurality of antennas to accommodate changes in subscriber traffic patterns, comprising:

coupling circuitry for connecting to a plurality of antennas;

a plurality of tree structured connecting circuits, each having a single terminal end and a plurality of bifurcating conducting branches deriving from the single terminal end and each of said bifurcating conducting branches having further bifurcating branches branches to provide a multiplicity of terminal ends;

the single terminal end of each of the plurality of tree structured connecting circuits being connected to the plurality of antennas respectively through the coupling circuitry,

the plurality of radio transceivers equaling the number of terminal ends of the multiplicity of terminal ends;

a plurality of multiple lead-to-single lead controlled switching devices sufficient in number so that each one of the multiple leads is associated with a corresponding selected individual terminal end of the number of a multiplicity of terminal ends of each of the plurality of tree structured connecting circuits and having its single lead connected to and operative to enable a connection from one of the multiple leads to a specific one of the plurality of radio transceivers,

signal attenuators inserted in individual transmission paths of the plurality of tree structured connecting circuits to equalize signal loss regardless of signal path length between the single terminal end and the multiplicity of terminal ends, and

a switch control connected to the switching devices and responsive to a control input representative of cellular phone traffic and operative for controlling switching states of the switching devices to control connection of a particular radio transceiver to a particular antenna.

2. In a cellular radiotelephone system a radio antenna interconnection arrangement as claimed in claim 1, wherein

the plurality of tree structured connecting circuits are deposited on individual substrates of a plurality of circuit substrates;

and

the switching devices are semiconductor switches mounted on one of the individual substrates.

3. In a cellular radiotelephone system a radio antenna interconnection arrangement for enabling connection of a plurality of radio transceivers to selected ones of a plurality of antennas to accommodate changes in subscriber traffic patterns, comprising:

coupling circuitry for connecting to first, second, third and fourth antennas;

first, second, third and fourth tree structured connecting circuits, each having a single terminal end and a plurality of bifurcating conducting branches deriving from the single terminal end and each of said bifurcating conducting branches having further bifurcating branches to provide a multiplicity of terminal ends;

the single terminal end of each of the first, second third and fourth tree structured connecting circuits being connected to the first, second, third and fourth antennas respectively through the coupling circuitry,

the plurality of radio transceivers equaling the number of terminal ends of the multiplicity of terminal ends;

a plurality of multiple lead-to-single lead controlled switching devices sufficient in number so that each one of the multiple leads is associated with a corresponding selected individual terminal end of the multiplicity of terminal ends of each of the first, second third and fourth tree structured connecting circuits and having its single lead connected to and operative to enable a connection from one of the multiple leads to a specific one of the plurality of radio transceivers,

signal attenuators inserted in individual transmission paths of the first, second third and fourth tree structured connecting circuits to equalize signal loss regardless of signal path length between the single terminal end and the multiplicity of terminal ends, and

a switch control connected to the switching devices and responsive to a control input representative of cellular phone traffic and operative for controlling switching states of the switching devices to control connection of a particular radio transceiver to a particular antenna.

4. In a cellular radiotelephone system a radio antenna interconnection arrangement as claimed in claim 3, wherein

the first, second third and fourth tree structured connecting circuits are deposited on individual substrates of a plurality of circuit substrates;

and

the switching devices are semiconductor switches mounted on one of the individual substrates.