Method for performing efficient ranging in a broadband wireless access system

A method of performing ranging with a base station in a broadband wireless access system, the method comprising:

• receiving a first ranging code for requesting ranging from a mobile station through a first ranging opportunity of a first frame;
• when the first ranging code is a dedicated ranging code previously allocated to the mobile station along with an identifier for the mobile station, transmitting a first message including a response “continue” to the first ranging code to the mobile station in a unicast manner based on the identifier;
• and
• transmitting, to the mobile station, uplink resource allocation information about an uplink resource through which the mobile station will transmit a second message through a first advanced MAP (A-MAP) information element (IE), upon successful reception of the first ranging code,
• wherein the first message includes a dedicated flag field,
• wherein when the dedicated flag field is set to ‘1’, the first message further includes a second ranging code, and information on a second ranging opportunity, and
• wherein the second ranging code is a dedicated ranging code which is different from the first ranging code.

A mobile station performing ranging in a broadband wireless access system, the mobile station comprising:

• a radio frequency (RF) module configured to transmit and receive RF signals;
• and
• a processor configured to control the RF module,
• wherein the processor is further configured to transmit, via the RF module, a first ranging code for requesting ranging to a base station through a first ranging opportunity of a first frame and to receive, via the RF module, a first message including a response to the first ranging code,
• wherein when the first ranging code is a dedicated ranging code and the response to the first ranging code is “continue”, the first message further includes a dedicated flag field,
• wherein when the dedicated flag field is set to ‘1’, the first message further includes a second ranging code, and information on a second ranging opportunity, and
• wherein the second ranging code is a dedicated ranging code which is different from the first ranging code.