Handover and call setup in a mobile communication system

• US 6,400,951 B1
• Filed: 08/26/1999
• Issued: 06/04/2002
• Est. Priority Date: 02/28/1997
• Status: Expired due to Fees

• Current Assignee: Nokia Telecommunications Oy (Nokia Corporation)
• Original Assignee: Nokia Telecommunications Oy (Nokia Corporation)
• Inventors: Vaara, Tomi
• Primary Examiner(s): Trost, William
• Assistant Examiner(s): Tran, Congvan
• Application Number:
  US09/387,718
• Time in Patent Office: 1,013 Days
• Field of Search: 455/414, 455/421, 455/432, 455/433, 455/434, 455/436, 455/437, 455/439, 455/442, 455/443, 455/512, 455/513, 370/331, 370/330, 370/329
• US Class Current: 455/436
• CPC Class Codes: H04W 36/26 by agreed or negotiated communication parameters
• CPC Class Codes: H04W 48/16 Discovering, processing access restriction or access information
• CPC Class Codes: H04W 8/18 Processing of user or subscriber data, e.g. subscribed services, user preferences or user profiles; Transfer of user or subscriber data
• CPC Class Codes: H04W 8/205 Transfer to or from user equipment or user record carrier

Abstract

An handover method and a call setup method in a mobile communication system. A cell to be assigned to the mobile station (MS) is selected on the basis of the measurement results and the special cell list. The selected cell is set as the target cell of the handover for the mobile station. The traffic channel for the mobile station (MS) is assigned from the base station of the selected cell.

Claims

1. A method for call setup in a mobile communication system which consists of base stations (BTS) and mobile stations (MS) and in which a special cell list has been created at least for some of the mobile stations (MS), said list being subscriber-specific and including priority cells and an identifier of at least one cell which offers special service to a mobile station, the mobile station locating in a camping cell, said method comprising:

measuring a signal level of a base station (BTS) of the camping cell and that of neighboring base stations of the base station, said measuring being performed in the mobile station (MS) and resulting in measurement results,

establishing a signaling connection between the base station (BTS) and the mobile station (MS),

transmitting the measurement results from the mobile station (MS) to the base station (BTS), and

transmitting the special cell list of the mobile station (MS) to a unit that controls the call setup,

comparing an identifier of the camping cell to the identifiers of cells listed in the special cell list of the mobile station (MS),

when the camping cell is a priority cell according to the special cell list, selecting the camping cell as the cell to be assigned to the mobile station, and

when the camping cell is not a priority cell according to the special cell list, performing the further steps of;

comparing identifiers of the cells suitable for the call setup on the basis of the measurement results to identifiers listed in the special cell list,

selecting a cell to be assigned to the mobile station, said cell being one of the cells suitable for the call setup and being defined as a priority cell according to the special cell, when such a priority cell is available, and

selecting a cell to be assigned to the mobile station, said cell being suitable for the call setup and being other than a cell defined as a priority cell according to the special cell list, when none of the cells suitable for the call setup are defined as a priority cell,

assigning a traffic channel to the mobile station (MS), said traffic channel being from the base station (BTS) of the cell selected.

2. The method according to claim 1, wherein the special cell list of the mobile station (MS) is transmitted from the mobile station (MS) to the base station controller (BSC).

3. The method according to claim 1, wherein the special cell list of the mobile station (MS) is transmitted from the mobile station (MS) to the base station controller (BSC) by using a signaling connection of the call setup.

4. The method according to claim 1, wherein the special cell list of the mobile station (MS) is transmitted to the base station controller (BSC), if necessary, during handover execution.

5. The method according to claim 1, wherein the special cell list of the mobile station (MS) is transmitted from the mobile services switching center (MSC) to the base station controller (BSC).

6. The method according to claim 1, wherein the special cell list is transmitted to the base station controller (BSC) during the call setup.