Methods, systems and devices for varying wireless transmit power based on path loss information
A method can include at a first station in a wireless network, receiving path loss (PL) transmissions from at least a second station, dynamically changing power for transmissions from the first station to the second station based on the received PL information, determining PL values for transmissions received at the first station from other stations, and sending PL transmissions from the first station that include the determined PL values for at least one other station. The PL transmissions are configured to be received by stations of the same wireless network and stations of a different wireless network. Corresponding devices and systems are also disclosed.
1 . A wireless device, comprising:
wireless communication circuits compatible with at least one 802.11 wireless standard and including:
a power control section configured to dynamically change transmission (TX) power for transmissions to a destination station device (STA) based on path loss (PL) information for the destination STA, the PL information corresponding to a loss in TX power from the wireless device to the destination STA;
a power detection section configured to detect a received signal strength of incoming beacon frames transmitted from other STAs; and
a PL section configured to:
extract multi-bit incoming PL information for each of a plurality of STAs from incoming beacon frames received from such STAs, the multi-bit incoming PL information for the incoming beacon frames corresponding to a same outgoing beacon frame from the wireless device and
determine multi-bit outgoing PL information for at least a first STA from at least one of the incoming beacon frames; wherein
the incoming beacon frames are beacon frames according to the at least one 802.11 wireless standard.
2 . The wireless device of claim 1 , wherein the PL section includes media access control (MAC) circuits in an integrated circuit device.
3 . The wireless device of claim 1 , wherein:
the PL section is further configured to:
include the outgoing PL information for at least one STA in an outgoing beacon frame, the outgoing beacon frame configured to be received by STAs of a same or different wireless network as the wireless device; and
the wireless device further comprising radio circuits configured to transmit the outgoing beacon frame.
4 . The wireless device of claim 3 , wherein:
the wireless device operates according to a predetermined communication standard; and
the radio circuits are configured to transmit the outgoing beacon frame at a maximum power according to the communication standard.
5 . The wireless device of claim 3 , wherein the radio circuits are configured to periodically transmit outgoing beacon frames.
6 . The wireless device of claim 1 , wherein:
the PL section includes at least one processor configurable to:
extract a TX power value from an incoming beacon frame received from a STA,
determine a received power value for the same incoming beacon frame, and
subtract the received power value from the TX power value.
7 . A wireless device, comprising:
communication circuits compatible with at least one 802.11 wireless standard and configured to receive incoming beacon frames that each include an information element (IE) with path loss (PL) values for a plurality of station device (STA) pairs, each PL value corresponding to a loss in transmit (TX) power from one STA to the other STA of the STA pair, the communication circuits including
a power control section configured to dynamically change a TX power for transmissions to a destination STA based on the PL value corresponding to such destination STA, and
a power detection section configured to detect a received signal strength of the incoming beacon frames, the incoming beacon frames configured to be received by a plurality of STAs and the wireless device essentially simultaneously; and
radio circuits configured to transmit frames to and receive frames from at least some of the plurality of STAs.
8 . The wireless device of claim 7 , wherein the IE further includes a device identification values and a corresponding PL value for each STA pair.
9 . The wireless device of claim 8 , wherein the device identification values comprise MAC addresses for the corresponding STA pairs.
10 . The wireless device of claim 7 , wherein:
the communication circuits are further configured to generate outgoing beacon frames that each include PL values from received beacon frames, as well as outgoing PL values, the communication circuits further including:
a PL calculation section configured to generate the outgoing PL values for other STAs from the received signal strength of transmissions received from such other STAs.
11 . The wireless device of claim 7 , wherein:
the communication circuits are further configured to:
if path loss value for a STA has been received within a time period, adjust transmission power of communications to the STA according to such PL value, and
if path loss value for the STA has not been received within the time period, setting a transmission power of communications to the STA to a maximum value.
12 . The wireless device of claim 7 , wherein the wireless device is a STA in a basic service set.
13 . The wireless device of claim 7 , wherein the wireless device is an access point of a basic service set.
14 . The wireless device of claim 7 , wherein:
the communication circuits are further configured to:
receive PL values for an out of network STA in an overlapping basic service set,
determine an estimated signal strength at the out of network STA for a transmission to an in network STA, the in network STA being part of a basic service set that includes the wireless device,
if the estimated signal strength at the out of network STA does not exceed a predetermined threshold, transmitting to the in network STA, and
if the estimated signal strength at the out of network STA does exceeds the predetermined threshold, delaying or abandoning the transmission to the in network STA.