Transmit power control for null data packets

A first communication device, comprising:

• a wireless network interface device that is configured to communicate in a wireless local area network (WLAN), the wireless network interface device having one or more integrated circuit (IC) devices configured to:
• generate a frame that includes an indication of a transmit power corresponding to one or more null data packets (NDPs) separate from the frame to permit a second communication device to determine a pathloss between the first communication device and the second communication device based on a received power of the one or more NDPs at the second communication device, wherein each of the one or more NDPs includes a physical layer (PHY) header and omits a Pi-1Y data portion,
• control the wireless network interface device to transmit the frame as part of a ranging measurement exchange, and
• as part of one or more ranging measurement exchanges, control the wireless network interface device to transmit the one or more NDPs in accordance with the transmit power indicated in the frame.

A method for performing ranging measurements in a wireless local area network (WLAN), the method comprising:

• during a ranging measurement exchange, receiving, at a first communication device, a frame that includes one or more indications of at least one of i) a transmit power corresponding to one or more first null data packets (NDPs) transmitted by a second communication device, and ii) a receive power corresponding to one or more second NDPs transmitted by the first communication device and received by the second communication device, wherein each of the one or more first NDPs and the one or more second NDPs includes a physical layer (PHY) header and omits a PHY data portion;
• calculating, at the first communication device, a pathloss between the first communication device and the second communication device using the one or more indications of the at least one of i) the transmit power corresponding to one or more first NDPs, and ii) the receive power corresponding to one or more second NDPs,
• using the calculated pathloss, selecting, by the first communication device, a transmit power of a first NDP to be transmitted to the first communication device;
• and
• transmitting, by the first communication device, the first NDP at the selected transmit power as part of a ranging measurement exchange.

A first communication device, comprising:

• a wireless network interface device that is configured to communicate in a wireless local area network (WLAN), the wireless network interface device having one or more integrated circuit (IC) devices configured to:
• during a ranging measurement exchange, receive a frame that includes one or more indications of at least one of i) a transmit power corresponding to one or more first null data packets (NDPs) transmitted by a second communication device, and ii) a receive power corresponding to one or more second NDPs transmitted by the first communication device and received by the second communication device, wherein each of the one or more first NDPs and the one or more second NDPs includes a physical layer (PHY) header and omits a PHY data portion,
• calculate a pathloss between the first communication device and the second communication device using the one or more indications of the at least one of i) the transmit power corresponding to one or more first NDPs, and ii) the receive power corresponding to one or more second NDPs,
• using the calculated pathloss, select a transmit power of a first NDP to be transmitted to the first communication device, and
• control the wireless network interface device to transmit the first NDP at the selected transmit power as part of a ranging measurement exchange.