Method and apparatus for enhanced call setup

• US 6,314,292 B1
• Filed: 08/15/1997
• Issued: 11/06/2001
• Est. Priority Date: 08/15/1997
• Status: Expired due to Term

• Current Assignee: Lenovo Innovation Company Limited Hong Kong (Lenovo Group Ltd.)
• Original Assignee: Nortel Networks Limited (Nortel Networks Corporation)
• Inventors: Ho, Joseph S. M., Xu, Jim
• Primary Examiner(s): Bost, Dwayne D.
• Assistant Examiner(s): Persino, Raymond B.
• Application Number:
  US08/911,628
• Time in Patent Office: 1,544 Days
• Field of Search: 455/450, 455/455, 455/509, 455/513, 455/464
• US Class Current: 455/450
• CPC Class Codes: H04W 72/00 Local resource management
• CPC Class Codes: H04W 76/10 Connection setup
• CPC Class Codes: H04W 84/042 Public Land Mobile systems, e.g. cellular systems

Abstract

A method is illustrated for reducing the call setup time of high priority calls such as voice or high speed user generated data without unduly wasting RF frequency resources on non priority calls such as short message calls. This is accomplished by ascertaining the call priority at the base station controller (BSC) level in a GSM system soon after call initiation and immediately changing the channel assignment for use by the remaining signalling type messages to a different operational speed where appropriate. The concept is further extended by supplying the call priority data to a called party'"'"'s BSC such that all signalling messages after initial contact can be at the operational speed appropriate to the priority of the call.

Claims

1. A method of assigning one of two different speed signaling channel types, f1 and f2, in response to signaling channel requests made prior to a communication and associated data pertaining to communication priority in a cellular communication network having a plurality of possible channels of each of types f1 and f2, the method comprising the steps, performed during call setup, of:

initially assigning a signaling channel type f1 in response to a channel request by a mobile station;

reading a service request message to make a determination of the service type requested;

changing during call setup to signaling channel type f2 in response to a determination that the service type requested is a signaling channel type f2; and

completing call setup using the signaling channel type requested in the service request message.

2. The method of claim 1 wherein the speed of the signaling channel type f1 is lower than the speed of the signaling channel type f2.

3. The method of claim 1 wherein the speed of the signaling channel type f2 is lower than the speed of the signaling channel type f1.

4. The method of claim 1 wherein:

the step of reading the service request message is accomplished by a base station controller of the network; and

the type f1 signaling channel is released for use by the network after a change in signaling channel type to type f2.

5. The method of claim 1 further comprising the additional step of transmitting the required channel type data to a base station controller serving the called mobile station prior to completing a mobile station terminating call, where the paging request message includes the required channel type data for optimizing the setup time required to communicate with the second mobile station.

6. The method of claim 1 wherein the two signaling channel types are the SDCCH (slow dedicated control channel) channel and the TCH/F (full speed traffic) channel.

7. A cellular system communication apparatus having two different speed signaling channel types, f1 and f2, the apparatus comprising, in combination:

a plurality of base transceiver stations operably interconnected to at least one mobile switching center;

first means for receiving channel requests from mobile stations wishing to communicate with another communication unit;

second means for supplying a default signaling channel assignment of type f1 in response to the channel requests from a mobile station by said first means;

third means for receiving a service request from a mobile station after the mobile station receives the default signaling channel assignment of type f1 from said second means;

fourth means for detecting the type of communication to be established with the mobile station from the contents of the received service request; and

fifth means for changing the signaling channel type assignment to f2 if the default signaling channel type does not match the service type requested in the service request before completing the remaining steps of call setup.

8. The apparatus as claimed in claim 7 wherein f1 is a lower speed communication channel than f2.

9. The apparatus as claimed in claim 7 wherein f2 is a lower speed communication channel than f1.

10. The apparatus as claimed in claim 7 wherein said cellular system is a GSM (Global System for Mobile communications) type system and the apparatus further comprises sixth means for transmitting channel type assignment data to a base station controller prior to completing a mobile station terminating call for optimizing the setup time required to establish communications with the called mobile station.

11. The apparatus as claimed in claim 7 wherein:

each of said first, second, third and fifth means constitutes a part of each of said base transceiver stations; and

said fourth means constitutes a part of a base station controller.

12. An early channel type assignment method for a cellular communication system comprising the steps of:

initially assigning one of two different speed signaling channels f1 and f2, upon receipt of a channel request from a mobile station, by a base station controller wherein the channel initially assigned is to be used to complete call setup and for communications after completion of call setup; and

immediately reassigning the mobile station to the other of said two different speed signaling channels f1 and f2 for completing call setup upon receipt of a CM service request message when, upon examination of the CM service request message by the base station controller, it is determined that the speed of the channel initially assigned does not match the speed of the channel requested in the CM service request message.

13. A cellular system communication apparatus, including at least base station controller and mobile switching center apparatus, having two different speed signaling channel types, f1 and f2, the apparatus comprising, in combination:

means for initially assigning one of two different speed signaling channels f1 and f2, upon receipt of a channel request from a mobile station; and

means for reassigning the mobile station to the other of said two different speed signaling channels f1 and f2 before completing call setup when, from examination of a CM service request message, it is determined that speed of the channel requested in the CM service request message does not match the speed of the channel initially assigned.

14. The apparatus as claimed in claim 13 wherein said cellular system is a GSM (Global System for Mobile communications) type system, the two different speed signaling channel types comprise the SDCCH (slow dedicated control channel) and the TCH/F (full speed traffic) channels and the apparatus further comprises means for transmitting channel type assignment data through a paging request message to a base station controller portion of the system prior to completing a mobile station terminating call for optimizing the setup time required to establish communications with the second mobile station.

15. A cellular system apparatus for assigning during call setup one of two different speed signaling channel types, f1 and f2, in response to signaling channel requests made prior to a communication and associated data pertaining to communication priority in a cellular communication network having a plurality of possible channels of each of types f1 and f2, the apparatus comprising in combination:

means for initially assigning a signaling channel type f1 in response to a channel request by a mobile station;

means for reading a service request message to make a determination of the service type requested;

means for changing during call setup to signaling channel type f2 in response to a determination that the service type requested is a signaling channel type f2; and

means for completing call setup using the signaling channel type requested in the service request message.