Ieee 802.11 enhancements for high efficiency positioning

Abstract

A ranging operation between an initiator device and a responder device may be performed by receiving, from the initiator device, a data frame including a request for the responder device to report its actual Short Interframe Space (SIFS) duration to the initiator device; creating a response frame; determining the actual SIFS duration based on the received data frame and the response frame; embedding SIFS information indicative of the actual SIFS duration of the responder device into the response frame; and sending the response frame to the initiator device.

What is claimed is: 
     
         1 . A method of performing a ranging operation between an initiator device and a responder device, the method performed by one or more processors of the responder device and comprising:
 receiving, from the initiator device, a data frame including a request for the responder device to report its actual Short Interframe Space (SIFS) duration to the initiator device;   creating a response frame;   determining the actual SIFS duration based on the received data frame and the response frame;   embedding SIFS information indicative of the actual SIFS duration of the responder device into the response frame; and   sending the response frame to the initiator device.   
     
     
         2 . The method of  claim 1 , wherein determining the actual SIFS duration comprises:
 determining a time of arrival (TOA) of the data frame;   determining a time of departure (TOD) of the response frame; and   determining the actual SIFS duration based at least in part on the determined TOA of the data frame and the determined TOD of the response frame.   
     
     
         3 . The method of  claim 1 , wherein the actual SIFS duration indicates a time duration between (1) a time that the responder device receives an end of a last symbol of the data frame from the initiator device and (2) a time that the responder device transmits a beginning of a first symbol of the response frame to the initiator device. 
     
     
         4 . The method of  claim 1 , wherein the data frame comprises a fine timing measurement (FTM) frame. 
     
     
         5 . The method of  claim 1 , wherein the data frame further comprises a request for the responder device to transmit the response frame using a high throughput (HT) or a very high throughput (VHT) protocol. 
     
     
         6 . The method of  claim 1 , wherein the response frame comprises an acknowledgement (ACK) frame including a field to store the SIFS information. 
     
     
         7 . The method of  claim 1 , wherein the SIFS information comprises a difference value indicative of a time difference between the actual SIFS duration and a standard SIFS duration. 
     
     
         8 . The method of  claim 7 , wherein the standard SIFS duration is defined by the IEEE 802.11 standards. 
     
     
         9 . The method of  claim 7 , wherein the response frame comprises an acknowledgement (ACK) frame including a first field to store the difference value and including a second field to store a median SIFS duration of the responder device. 
     
     
         10 . The method of  claim 1 , wherein:
 the data frame further comprises a request for the responder device to use a single transmit chain to transmit the response frame to the initiator device.   
     
     
         11 . A responder device configured to perform a ranging operation with an initiator device, the responder device comprising:
 one or more transceivers to exchange signals with at least the initiator device;   one or more processors; and   a memory storing instructions that, when executed by the one or more processors, cause the responder device to:
 receive, from the initiator device, a data frame including a request for the responder device to report its actual Short Interframe Space (SIFS) duration to the initiator device; 
 create a response frame; 
 determine the actual SIFS duration of the responder device based on the received data frame and the response frame; 
 embed SIFS information indicative of the actual SIFS duration into the response frame; and 
 send the response frame to the initiator device. 
   
     
     
         12 . The responder device of  claim 11 , wherein execution of the instructions to determine the actual SIFS duration causes the responder device to:
 determine a time of arrival (TOA) of the data frame;   determine a time of departure (TOD) of the response frame; and   determine the actual SIFS duration based at least in part on the determined TOA of the data frame and the determined TOD of the response frame.   
     
     
         13 . The responder device of  claim 11 , wherein the data frame comprises a fine timing measurement (FTM) frame. 
     
     
         14 . The responder device of  claim 11 , wherein the data frame further comprises a request for the responder device to transmit the response frame using a high throughput (HT) or a very high throughput (VHT) protocol. 
     
     
         15 . The responder device of  claim 11 , wherein the response frame comprises an acknowledgement (ACK) frame including a field to store the SIFS information. 
     
     
         16 . The responder device of  claim 11 , wherein the SIFS information comprises a difference value indicative of a time difference between the actual SIFS duration and a standard SIFS duration. 
     
     
         17 . The responder device of  claim 16 , wherein the response frame comprises an acknowledgement (ACK) frame including a first field to store the difference value and including a second field to store a median SIFS duration of the responder device. 
     
     
         18 . The responder device of  claim 11 , wherein:
 the data frame further comprises a request for the responder device to use a single transmit chain to transmit the response frame to the initiator device.   
     
     
         19 . A responder device configured to perform a ranging operation with an initiator device, the responder device comprising:
 means for receiving, from the initiator device, a data frame including a request for the responder device to report its actual Short Interframe Space (SIFS) duration to the initiator device;   means for creating a response frame;   means for determining the actual SIFS duration of the responder device based on the received data frame and the response frame;   means for embedding SIFS information indicative of the actual SIFS duration into the response frame; and   means for sending the response frame to the initiator device.   
     
     
         20 . The responder device of  claim 19 , wherein the means for determining the actual SIFS duration is to:
 determine a time of arrival (TOA) of the data frame;   determine a time of departure (TOD) of the response frame; and   determine the actual SIFS duration based at least in part on the determined TOA of the data frame and the determined TOD of the response frame.   
     
     
         21 . The responder device of  claim 19 , wherein the data frame comprises a fine timing measurement (FTM) frame. 
     
     
         22 . The responder device of  claim 19 , wherein the response frame comprises an acknowledgement (ACK) frame including a field to store the SIFS information. 
     
     
         23 . The responder device of  claim 19 , wherein the SIFS information comprises a difference value indicative of a time difference between the actual SIFS duration and a standard SIFS duration. 
     
     
         24 . The responder device of  claim 23 , wherein the response frame comprises an acknowledgement (ACK) frame including a first field to store the difference value and including a second field to store a median SIFS duration of the responder device. 
     
     
         25 . A non-transitory computer-readable storage medium storing one or more programs containing instructions that, when executed by one or more processors of a responder device, cause the responder device to perform operations comprising:
 receiving, from the initiator device, a data frame including a request for the responder device to report its actual Short Interframe Space (SIFS) duration to the initiator device;   creating a response frame;   determining the actual SIFS duration based on the received data frame and the response frame;   embedding SIFS information indicative of the actual SIFS duration into the response frame; and   sending the response frame to the initiator device.   
     
     
         26 . The non-transitory computer-readable storage medium of  claim 25 , wherein execution of the instructions to determine the actual SIFS duration causes the responder device to:
 determine a time of arrival (TOA) of the data frame;   determine a time of departure (TOD) of the response frame; and   determine the actual SIFS duration based at least in part on the determined TOA of the data frame and the determined TOD of the response frame.   
     
     
         27 . The non-transitory computer-readable storage medium of  claim 25 , wherein the data frame comprises a fine timing measurement (FTM) frame. 
     
     
         28 . The non-transitory computer-readable storage medium of  claim 25 , wherein the response frame comprises an acknowledgement (ACK) frame including a field to store the SIFS information. 
     
     
         29 . The non-transitory computer-readable storage medium of  claim 25 , wherein the SIFS information comprises a difference value indicative of a time difference between the actual SIFS duration and a standard SIFS duration. 
     
     
         30 . The non-transitory computer-readable storage medium of  claim 29 , wherein the response frame comprises an acknowledgement (ACK) frame including a first field to store the difference value and including a second field to store a median SIFS duration of the responder device.