Relative positioning applications in wireless devices

Abstract

Techniques for determining whether a mobile device crosses a boundary defined by a first wireless access point (WAP) and a second fixed-location WAP are provided. A method according to these techniques includes receiving, at a mobile device, information defining a boundary defined by first and second fixed-location WAPs, the boundary being defined at least in part based on a ratio of a round trip time (RTT) between the mobile device and the first fixed-location WAP to a ratio of a RTT between the mobile device and the second fixed-location WAP, determining the ratio of the RTT between the mobile device and the first fixed-location WAP to a ratio of the RTT between the mobile device and the second fixed-location WAP, determining whether the mobile device has crossed the boundary, and triggering an event in response to the mobile device crossing the boundary.

What is claimed is: 
     
         1 . A method for controlling access to electronic content at a wireless access point, the method comprising:
 measuring a round-trip time (RTT) associated with signals transmitted between a mobile device and the wireless access point to determine a measured RTT;   receiving an RTT reference value associated with access to the electronic content;   comparing the measured RTT with the RTT reference value; and   providing permission to access the electronic content to the mobile device depending, at least in part, on the measured RTT having a desired relationship to the RTT reference value.   
     
     
         2 . The method of  claim 1  wherein providing the permission to access the electronic content comprises sending an instruction to a server to push the electronic content to the mobile device. 
     
     
         3 . The method of  claim 1  wherein providing the permission to access the electronic content to the mobile device further comprises:
 authenticating the mobile device to determine whether the mobile device is authorized to access the electronic content, 
 wherein the permission to access the electronic content is provided to the mobile device only if the mobile device is authorized to access the electronic content, wherein whether the mobile device is authorized is based, at least in part, on authentication of the mobile device. 
 
     
     
         4 . The method of  claim 3  wherein authenticating the mobile device to determine whether the mobile device is authorized to access the electronic content includes comparing a Media Access Control (MAC) address of the mobile device to a set of authorized MAC addresses to determine whether the mobile device is authorized to access the electronic content. 
     
     
         5 . An apparatus for controlling access to electronic content at a wireless access point comprising:
 means for measuring a round-trip time (RTT) associated with a signal transmitted between a mobile device and the wireless access point to determine a measured RTT;   means for receiving an RTT reference value associated with access to the electronic content;   means for comparing the measured RTT with the RTT reference value; and   means for providing permission to access the electronic content to the mobile device depending, at least in part, on the measured RTT having a desired relationship to the RTT reference value.   
     
     
         6 . The apparatus of  claim 5  wherein the means for providing the permission to access the electronic content comprises means for sending a message to a server to push the electronic content to the mobile device. 
     
     
         7 . The apparatus of  claim 5 , wherein the means for providing the permission to access the electronic content comprises:
 means for authenticating the mobile device to determine whether the mobile device is authorized to access the electronic content,   wherein the permission to access the electronic content is provided to the mobile device only if the mobile device is authorized to access the electronic content, wherein whether the mobile device is authorized is based, at least in part, on authentication of the mobile device.   
     
     
         8 . The apparatus of  claim 7  wherein the means for authenticating the mobile device to determine whether the mobile device is authorized to access the electronic content includes means for comparing a Media Access Control (MAC) address of the mobile device to a set of authorized MAC addresses to determine whether the mobile device is authorized to access the electronic content. 
     
     
         9 . A computer-readable storage medium, having stored thereon computer-readable instructions for controlling access to electronic content at a wireless access point, comprising instructions configured to cause at least one processor to:
 measure a round-trip time (RTT) associated with a signal transmitted between a mobile device and the wireless access point to determine a measured RTT;   receive a RTT reference value associated with access to the electronic content;   compare the measured RTT with the RTT reference value; and   provide permission to access the electronic content to the mobile device depending, at least in part, on the measured RTT having a desired relationship to the RTT reference value.   
     
     
         10 . The computer-readable storage medium of  claim 9  wherein the instructions to cause the at least one processor to provide the permission to access the electronic content comprise instructions to cause the at least one processor to send a message to a server to push content the electronic content to the mobile device. 
     
     
         11 . The computer-readable storage medium of  claim 9  wherein the instructions to cause the at least one processor to provide the permission to access the electronic content at the wireless access point further comprise instructions to cause the at least one processor to:
 authenticate the mobile device to determine whether the mobile device is authorized to access the electronic content; and 
 wherein the permission to access the electronic content is provided to the mobile device only if the mobile device is authorized to access the electronic content, wherein whether the mobile device is authorized is based, at least in part, on authentication of the mobile device. 
 
     
     
         12 . The computer-readable storage medium of  claim 11  wherein the instructions to cause the at least one processor to authenticate the mobile device to determine whether the mobile device is authorized to access the electronic content include instructions to cause the at least one processor to compare a Media Access Control (MAC) address of the mobile device to a set of authorized MAC addresses to determine whether the mobile device is authorized to access the electronic content. 
     
     
         13 . An apparatus for controlling access to electronic content at a wireless access point comprising:
 a wireless transceiver for transmitting signals to and receiving signals from the wireless access point;   a non-transitory computer-readable memory;   a plurality of modules comprising processor executable code stored in the non-transitory computer-readable memory;   a processor connected to the non-transitory computer-readable memory and configured to access the plurality of modules stored in the non-transitory computer-readable memory; and   a relative positioning module configured to
 measure a round-trip time (RTT) associated with a signal transmitted between a mobile device and the wireless access point to determine a measured RTT; 
   a content control module configured to
 receive a RTT reference value associated with access to the electronic content; and 
 compare the measured RTT with the RTT reference value; and 
 provide permission to access the electronic content to the mobile device depending, at least in part, on the measured RTT having a desired relationship to the RTT reference value. 
   
     
     
         14 . The apparatus of  claim 13  wherein the content control module being configured to provide the permission to access the electronic content is further configured to send a message to a server to push content to the mobile device. 
     
     
         15 . The apparatus of  claim 13 , wherein the content control module being configured to provide the permission to access the electronic content to the mobile device is further configured to:
 authenticate the mobile device to determine whether the mobile device is authorized to access the electronic content; and   wherein the permission to access the electronic content is provided to the mobile device only if the mobile device is authorized to access the electronic content, wherein whether the mobile device is authorized is based, at least in part, on authentication of the mobile device.   
     
     
         16 . The apparatus of  claim 15  wherein the content control module being configured to authenticate the mobile device to determine whether the mobile device is authorized to access the electronic content is further configured to compare a Media Access Control (MAC) address of the mobile device to a set of authorized MAC addresses to determine whether the mobile device is authorized to access the electronic content. 
     
     
         17 . A method for sharing electronic content between mobile wireless devices, the method comprising:
 measuring a round-trip time (RTT) associated with signals transmitted between a first mobile device and a second mobile device, the signals being transmitted directly from the first mobile device to the second mobile device without being routed through a wireless network providing wireless network access to the first mobile device or the second mobile device to determine a measured RTT;   comparing the measured RTT with an RTT reference value; and   providing permission to access the electronic content associated with the first mobile device to the second mobile device responsive to the measured RTT having a desired relationship to the RTT reference value.   
     
     
         18 . The method of  claim 17  wherein providing the permission to access the electronic content associated with the first mobile device to the second mobile device further comprises:
 pushing content from the first mobile device to the second mobile device. 
 
     
     
         19 . The method of  claim 17  wherein providing the permission to access the electronic content associated with the first mobile device to the second mobile device further comprises:
 providing a network address to the second mobile device at which the second mobile device can access the electronic content. 
 
     
     
         20 . The method of  claim 17  further comprising:
 repeatedly measuring the RTT associated with additional signals transmitted between the first mobile device and the second mobile device after providing the permission to access the electronic content associated with the first mobile device to the second mobile device; and 
 revoking access to the electronic content by the second mobile device if the second mobile device moves further than a predetermined distance from the first mobile device. 
 
     
     
         21 . An apparatus for sharing electronic content between mobile wireless devices comprising:
 means for measuring a round-trip time (RTT) associated with signals transmitted between a first mobile device and a second mobile device, the signals being transmitted directly from the first mobile device to the second mobile device without being routed through a wireless network providing wireless network access to the first mobile device or the second mobile device to determine a measured RTT;   means for comparing the measured RTT with an RTT reference value; and   means for providing permission to access the electronic content on the first mobile device to the second mobile device responsive to the measured RTT having a desired relationship to the RTT reference value.   
     
     
         22 . The apparatus of  claim 21  wherein the means for providing the permission to access the electronic content on the first mobile device to the second mobile device further comprises:
 means for pushing the electronic content from the first mobile device to the second mobile device. 
 
     
     
         23 . The apparatus of  claim 21  wherein the means for providing the permission to access the electronic content on the first mobile device to the second mobile device further comprises:
 means for providing a network address to the second mobile device at which the second mobile device can access the electronic content. 
 
     
     
         24 . The apparatus of  claim 21  further comprising:
 means for repeatedly measuring the RTT associated with additional signals transmitted between the first mobile device and the second mobile device after providing the permission to access the electronic content associated with the first mobile device to the second mobile device; and 
 means for revoking access to the electronic content by the second mobile device if the second mobile device moves further than a predetermined distance from the first mobile device. 
 
     
     
         25 . A computer-readable storage medium, having stored thereon computer-readable instructions for sharing electronic content between mobile wireless devices, comprising instructions configured to cause at least one processor to:
 measure a round-trip time (RTT) associated with signals transmitted between a first mobile device and a second mobile device, the signals being transmitted directly from the first mobile device to the second mobile device without being routed through a wireless network providing wireless network access to the first mobile device or the second mobile device to determine a measured RTT;   compare the measured RTT with an RTT reference value; and   provide permission to access the electronic content on the first mobile device to the second mobile device responsive to the measured RTT having a desired relationship to the RTT reference value.   
     
     
         26 . The computer-readable storage medium of  claim 25  wherein the instructions configured to provide the permission to access the electronic content on the first mobile device to the second mobile device further comprise instructions to cause the at least one processor to:
 push the electronic content from the first mobile device to the second mobile device. 
 
     
     
         27 . The computer-readable storage medium of  claim 25  wherein the instructions configured to provide the permission to access the electronic content on the first mobile device to the second mobile device further comprise instructions to cause the at least one processor to:
 provide a network address to the second mobile device at which the second mobile device can access the electronic content. 
 
     
     
         28 . The computer-readable storage medium of  claim 25  further comprising instructions to cause the at least one processor to:
 repeatedly measure the RTT associated with additional signals transmitted between the first mobile device and the second mobile device after providing the permission to access the electronic content associated with the first mobile device to the second mobile device; and 
 revoke access to the electronic content by the second mobile device if the second mobile device moves further than a predetermined distance from the first mobile device. 
 
     
     
         29 . An apparatus for sharing electronic content between mobile wireless devices comprising:
 a non-transitory computer-readable memory;   a plurality of modules comprising processor executable code stored in the non-transitory computer-readable memory;   a processor connected to the non-transitory computer-readable memory and configured to access the plurality of modules stored in the non-transitory computer-readable memory; and   a relative positioning module configured to
 measure a round-trip time (RTT) associated with signals transmitted between a first mobile device and a second mobile device to determine a measured RTT; and 
   a content control module configured to
 compare the measured RTT with an RTT reference value; and 
 provide permission to access the electronic content on the first mobile device to the second mobile device responsive to the measured RTT having a desired relationship to the RTT reference value. 
   
     
     
         30 . The apparatus of  claim 29  wherein the content control module being configured to provide the permission to access the electronic content on the first mobile device to the second mobile device is further configured to:
 push the electronic content from the first mobile device to the second mobile device. 
 
     
     
         31 . The apparatus of  claim 29  wherein the content control module being configured to provide the permission to access the electronic content on the first mobile device to the second mobile device is further configured to:
 provide a network address to the second mobile device at which the second mobile device can access the electronic content. 
 
     
     
         32 . The apparatus of  claim 29  wherein the content control module is configured to:
 instruct the relative positioning module to repeatedly measure the RTT associated with additional signals transmitted between the first mobile device and the second mobile device after the content control module has provided access to the electronic content on the first mobile device to the second mobile device; and 
 revoke access to the electronic content by the second mobile device if the second mobile device moves further than a predetermined distance from the first mobile device.