Method and apparatus for controlling a small cell on or off procedure for coverage extension

A method for controlling a small cell off procedure by a Macro Serving Cell (MSC), the method comprising:

• transmitting, by a Source Small Cell (SSC) to the MSC, a Cell Off Indication message including a Cell State Change Indication parameter indicating a cell status of the SSC, a Time to Start Cell Off parameter indicating when the small cell off procedure is started, and a Cell Off Timer indicating a time period during which the small cell off procedure is performed;
• receiving, by the SSC from the MSC, an Expand Indication message indicating an expanding of the MSC when the Cell State Change Indication parameter indicates a cell off status;
• and
• starting the small cell off procedure at a time indicated by the Time to Start Cell Off parameter before an expiration of the time period indicated by the Cell Off Timer.

A Macro Serving Cell (MSC) for controlling a small cell off procedure in a wireless access system, the MSC comprising:

• a transmitter;
• a receiver;
• and
• a processor for controlling the small cell off procedure and expanding of the MSC,
• wherein the processor is configured to:
• receive, via the receiver from a Source Small Cell (SSC), a Cell Off Indication message including a Cell State Change Indication parameter indicating a cell status of the SSC;
• transmit, via the transmitter to the SSC, an Expand Indication message indicating an expanding of the MSC when the Cell State Change Indication parameter indicates a cell off status, the Expanding Indication message including a Time to Start Expand parameter indicating when the MSC starts an expanding of its coverage and an Expand Timer parameter indicating a time period during which the expanding is performed;
• and
• start the expanding of its coverage at a time indicated by the Time to Start Expand parameter during the time period indicated by the Expand Timer.