USSD-facilitated call setup for push to talk over cellular (PoC) services
US7289816B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Nov 23, 2004 |
| Grant date | Oct 30, 2007 |
| Priority date | — |
| Expiry date | Sep 17, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04W76/45
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A method of setting up a Push-To-Talk-over-Cellular (PoC) call between a calling mobile station (MS) and a called MS in a cellular communications network. In GSM/GPRS networks, the method decreases the call setup time, from the time the push-to-talk button is pressed, by causing the called MS to change to READY state before call setup is initiated. This is done by sending a USSD message to the called MS when the calling user selects a PoC contact list on the calling MS. The USSD message causes the called MS to perform a routing area update and change to READY state. This eliminates the need to page the called MS during call setup. In WCDMA networks, the USSD message causes the called MS to reestablish a Radio Resource Control (RRC) connection. The called MS maintains this connection, thereby enabling faster type 2 paging to be utilized for call setup.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.