Method and device for transmitting and receiving traffic indication map in wireless LAN system

A method for transmitting a Traffic Indication Map (TIM) element by an Access Point (AP) in a Wireless Local Area Network (WLAN) system, the method comprising:

• encoding a partial virtual bitmap;
• and
• transmitting the TIM element including the encoded partial virtual bitmap to a Station (STA),
• wherein one block of the partial virtual bitmap includes an Encoding Word Length (EWL) field, a Length field, one or more Association Identifier (ΔAID) Differential Value fields, and a field following the one or more ΔAID Differential Value fields, and
• wherein the one block of the partial virtual bitmap includes an indication to stop decoding the one block.

A Station (STA) for receiving a Traffic Indication Map (TIM) element in a Wireless Local Area Network (WLAN) system, the STA comprising:

• a transceiver;
• and
• a processor,
• wherein the processor is configured to receive a frame including the TIM element from an Access Point (AP) through the transceiver, and to decode a partial virtual bitmap included in the TIM element,
• wherein one block of the partial virtual bitmap includes an Encoding Word Length (EWL) field, a Length field, one or more Association Identifier (ΔAID) Differential Value fields, and a field following the one or more ΔAID Differential Value fields, and
• wherein the processor stops decoding the one block of the partial virtual bitmap based on an indication in the one block.

An Access Point (AP) for transmitting a Traffic Indication Map (TIM) element in a Wireless Local Area Network (WLAN) system, the AP comprising:

• a transceiver;
• and
• a processor,
• wherein the processor is configured to encode a partial virtual bitmap, and to transmit the TIM element including the encoded partial virtual bitmap to a Station (STA) through the transceiver,
• wherein one block of the partial virtual bitmap includes an Encoding Word Length (EWL) field, a Length field, one or more Association Identifier (ΔAID) Differential Value fields, and a field following the one or more ΔAID Differential Value fields, and
• wherein the one block of the partial virtual bitmap includes an indication to stop decoding the one block.