Method and apparatus for handover by changing zones in a wireless communication system

A method of providing handover of a mobile station (MS) from a first type serving base station to a second type target base station, the method comprising:

• receiving, after a network entry of the MS to the first type serving base station is performed, a ranging request (RNG-REQ) message from the MS by the second type target base station through a first type MS support zone, the RNG-REQ message including a field for requesting zone switching from the first type MS support zone of the second type target base station to a second type MS support zone of the second type target base station;
• transmitting, by the second type target base station, a ranging response (RNG-RSP) message to the MS through the first type MS support zone, the RNG-RSP message including a field indicating omission of a first type capability negotiation message for a network re-entry to the second type target base station;
• and
• receiving, by the second type target base station, a second type capability request message from the MS through the second type MS support zone,
• wherein an authentication procedure is not performed during the network re-entry to the second type target base station, and
• if uplink grant is not included in the RNG-RSP message, performing a first bandwidth request (BR) procedure or a second BR procedure,
• wherein the first BR procedure includes:
• receiving a BR code for a BR message by the second target base station from the MS through the second type MS support zone;
• transmitting uplink grant for the BR message by the second type target base station from the MS through the second type MS support zone;
• receiving the BR message by the second type target base station from the MS using uplink resources indicated by the uplink grant for the BR message;
• and
• transmitting the uplink grant for the second type capability request message by the second type target base station to the MS through the second type MS support zone as a response to the BR message;
• and
• wherein the second BR procedure includes:
• transmitting a BR message for the second type capability request message to the second type target base station through the second type MS support zone along with a BR code;
• and
• receiving uplink grant for the second type capability request message from the second type target base station through the second type MS support zone as a response to the BR message.

A mobile station (MS) which performs handover from a first type serving base station to a second type target base station, the MS comprising:

• a processor;
• a reception module;
• a transmission module;
• and
• at least one antenna,
• wherein the processor is configured to:
• perform a network entry to the first type serving base station;
• transmit, after the network entry to the first type serving base station, a ranging request (RNG-REQ) message to the second type target base station through a first type MS support zone, the RNG-REQ message including a field for requesting zone switching from the first type MS support zone of the second type target base station to a second type MS support zone, through the transmission module;
• receive a ranging response (RNG-RSP) message from the second type target base station through the first type MS support zone, the RNG-RSP message including a field indicating omission of a first type capability negotiation message for a network re-entry to the second type target base station, through the reception module;
• and
• transmit a second type capability request message to the second type target base station through the second type MS support zone, through the transmission module,
• wherein an authentication procedure is not performed during the network re-entry to the second type target base station, and
• wherein a first bandwidth request (BR) procedure or a second BR procedure is performed if uplink grant is not included in the RNG-RSP message,
• wherein to perform the first BR procedure the processor is further configured to:
• transmit a BR code for a BR message to the second target base station through the second type MS support zone, through the transmission module;
• receive uplink grant for the BR message from the second type target base station through the second type MS support zone, through the reception module;
• transmit the BR message using uplink resources indicated by the uplink grant for the BR message, to the second target base station through the transmission module;
• and
• receive the uplink grant for the second type capability request message from the second type target base station through the second type MS support zone as a response to the BR message, through the reception module;
• and
• wherein to perform the second BR procedure the processor is further configured to:
• transmit a BR message for the second type capability request message to the second type target base station through the second type MS support zone along with a BR code, through the transmission module;
• and
• receive the uplink grant for the second type capability request message from the second type target base station through the second type MS support zone as a response to the BR message, through the reception module.

A second type target base station to which handover of a mobile station (MS) from a first type serving base station is performed, the second type target base station comprising:

• a processor;
• a reception module;
• a transmission module;
• and
• an antenna,
• wherein the processor is configured to:
• receive, after a network entry of the MS to the first type serving base station is performed, a ranging request (RNG-REQ) message from the MS through a first type MS support zone, the RNG-REQ message including a field for requesting zone switching from the first type MS support zone of the second type target base station to a second type MS support zone of the second type target base station, through the reception module;
• transmit a ranging response (RNG-RSP) message to the MS through the first type MS support zone, the RNG-RSP message including a field indicating omission of a first type capability negotiation message for a network re-entry to the second type target base station, through the transmission module;
• and
• receive a second type capability request message from the MS through the second type MS support zone, through the reception module,
• wherein an authentication procedure is not performed during the network re-entry to the second type target base station, and
• wherein a first bandwidth request (BR) procedure or a second BR procedure is performed if uplink grant is not included in the RNG-RSP message,
• wherein to perform the first BR procedure the processor is further configured to:
• receive a BR code for a BR message from the MS through the second type MS support zone, through the reception module;
• transmit uplink grant for the BR message from the MS through the second type MS support zone, through the transmission module;
• receive the BR message from the MS using uplink resources indicated by the uplink grant for the BR message, through the reception module;
• and
• transmit the uplink grant for the second type capability request message to the MS through the second type MS support zone as a response to the BR message, through the transmission module;
• and
• wherein to perform the second BR procedure the processor is further configured to:
• transmit a BR message for the second type capability request message to the second type target base station through the second type MS support zone along with a BR code, through the transmission module;
• and
• receive the uplink grant for the second type capability request message from the second type target base station through the second type MS support zone as a response to the BR message, through the reception module.