Patent EP0544457A2 successfully refreshed from Google Patents.
EP0544457A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Handover of mobile radio calls between base station systems
Assignee: AT&T Inc
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Filing: 1992-11-19
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Granted: —
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Expires: 2012-11-19
Abstract
Abstract This invention relates to apparatus and methods for providing cellular mobile telecommunication service in accordance with the requirements of the Global Systems for Mobile Communications (GSM) standard. A modular switching system is provided which performs the functions of the mobile switching center (210) plus those of a home location register (212), authentication center (216), visitor location register (214), and equipment identity register (218). The latter functions are advantageously spread among the modules of the switching system, thus avoiding the getting started cost of expensive dedicated data bases. A wireless global switching module advantageously switches mobile communications control messages among the modules of the system and between the modules and the base station systems (204), and terminates signaling links between the mobile switching center and the base station systems.
Inventors
- 👤 Chinmei Chen Lee
- 👤 James Joseph Phelan
- 👤 Luat Tan Phung
- 👤 Alex Lawrence Wierzbicki
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-30 20:27
CPC Classifications
H; H04; H04W; H04W36/00; H04W36/12
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
126 words
In a cellular mobile telecommunications switching system, a method of handing over communications between a mobile radio station and said switching system from a first base station system to a second base station system, a communication path to said mobile station initially comprising a connection from an input to a first output of a switch of said switching system, comprising the ordered steps of: establishing a connection from a second output of said switch to said second base station system; sending a request to said first base station to cause said mobile station to retune to a channel of said second base station; and concurrently connecting said input to said switch to said second output and disconnecting said input from said first output of said switch.
Claim 2
Dependent Claim
126 words
In a cellular mobile telecommunications switching system, a method of handing over communications between a mobile radio station and said switching system from a first base station system to a second base station system, a communication path to said mobile station initially comprising a connection from an input to a first output of a switch of said switching system, comprising the ordered steps of: establishing a connection from a second output of said switch to said second base station system; sending a request to said first base station to cause said mobile station to retune to a channel of said second base station; and concurrently connecting said input to said switch to said second output and disconnecting said input from said first output of said switch.
Claim 3
Dependent Claim
44 words
The method of claim 1 wherein said concurrently connecting step comprises the step: changing a control memory of a time slot interchange of said switch to steer time slots formerly steered from and to said first output instead from and to said second output.
Claim 4
Dependent Claim
75 words
The method of claim 1 wherein said sending step comprises sending a signal requesting said mobile to send a signal from said mobile station to said second base station system over a channel of said second base station system further comprising: receiving a message from said second base station system to said switching system to perform the concurrently connecting step in response to said second base station system detecting said signal from said mobile station.
Claim 5
Dependent Claim
55 words
The method of claim 1 further comprising: prior to said establishing step, said first base station receiving signal strength measurement data from said mobile station; and determining whethera handoverto a transceiver served by another base station system is required and responsive to said determination, transmitting a request to initiate a handover to said switching system.
Claim 6
Dependent Claim
140 words
In a cellular mobile telecommunications switching system, apparatus for handing over communications between a mobile radio station and said switching system from a first base station system to a second base station system, comprising: a switching network having an initial connection from an input to a first output of said switching network; and processor means operative under the control of a program for controlling establishment of a connection from a second output of said switching network to said second base station system; for controlling said first base station system to send a signal to said mobile unit to retune to a channel of said second base station system; and for controlling the concurrent connection of said input to a second output connected to said second base station system and disconnecting said input from said first output of said switching network.
Claim 7
Dependent Claim
140 words
In a cellular mobile telecommunications switching system, apparatus for handing over communications between a mobile radio station and said switching system from a first base station system to a second base station system, comprising: a switching network having an initial connection from an input to a first output of said switching network; and processor means operative under the control of a program for controlling establishment of a connection from a second output of said switching network to said second base station system; for controlling said first base station system to send a signal to said mobile unit to retune to a channel of said second base station system; and for controlling the concurrent connection of said input to a second output connected to said second base station system and disconnecting said input from said first output of said switching network.
Claim 8
Dependent Claim
22 words
The apparatus of claim 5 wherein said switching system is modular and said processor means comprises module processor means for each module.
Claim 9
Dependent Claim
30 words
The apparatus of claim 6 wherein a first module processor means controls said establishment and said concurrent connection and a second module processor means controls said first base station system.
References Cited (Backward Citations)
No citation records indexed.
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