TECHNIQUES FOR COMPRESSING RF HEAT MAPS FOR ACCESS POINTS
Techniques for providing access point (AP) vicinity information are disclosed. In one example, the techniques include determining a first set of vicinity information corresponding to signal values for an AP at a set of grid points for the coverage area of the AP, encoding the first set of AP vicinity information based at least on a difference between AP vicinity information values for adjacent grid points to generate a second set of AP vicinity information, and providing the second set of AP vicinity information to a device. In one example, the techniques include receiving, for a set of grid points, a first set of AP vicinity information that is compressed based at least on a difference between AP vicinity information values for adjacent grid points, and performing decompression to obtain a second set of AP vicinity information corresponding to signal values for an AP at the set of grid points.
1 . A method for providing access point (AP) vicinity information, comprising:
determining a first set of AP vicinity information for a set of grid points for a coverage area of an AP;
encoding the first set of AP vicinity information based at least on a difference between AP vicinity information values for adjacent grid points to generate a second set of AP vicinity information; and
providing the second set of AP vicinity information to a mobile device.
2 . The method of claim 1 , wherein encoding the first set of AP vicinity information comprises:
determining a plurality of delta values comprising differences between AP vicinity information values for adjacent grid points; and
compressing at least some of the plurality of delta values to generate the second set of AP vicinity information.
3 . The method of claim 2 , wherein the plurality of delta values are compressed based on two or more delta ranges.
4 . The method of claim 3 , wherein the two or more delta ranges comprise a low-range, mid-range and high-range.
5 . The method of claim 2 , further comprising:
determining a plurality of double delta values comprising differences between the plurality of delta values for adjacent grid points; and wherein the second set of AP vicinity information is generated by compressing at least some of the plurality of double delta values.
6 . The method of claim 1 , wherein the first set of AP vicinity information comprises mean received signal strength for the AP at a plurality of locations.
7 . The method of claim 1 , wherein the first set of AP vicinity information comprises mean round trip time for signal propagation between each grid point in the set of grid points and the AP.
8 . The method of claim 1 , wherein the second set of AP vicinity information comprises a sequence of compressed values.
9 . An apparatus for providing access point (AP) vicinity information, comprising:
means for determining a first set of AP vicinity information for a set of grid points for a coverage area of an AP;
means for encoding the first set of AP vicinity information based at least on a difference between AP vicinity information values for adjacent grid points to generate a second set of AP vicinity information; and
means for providing the second set of AP vicinity information to a mobile device.
10 . The apparatus of claim 9 , wherein the means for encoding the first set of AP vicinity information comprises:
means for determining a plurality of delta values comprising differences between AP vicinity information values for adjacent grid points; and
means for compressing at least some of the plurality of delta values to generate the second set of AP vicinity information.
11 . The apparatus of claim 10 , wherein the plurality of delta values are compressed based on two or more delta ranges.
12 . The apparatus of claim 11 , wherein the two or more delta ranges comprise a low-range, mid-range and high-range.
13 . The apparatus of claim 10 , further comprising:
means for determining a plurality of double delta values comprising differences between the plurality of delta values for adjacent grid points; and wherein the second set of AP vicinity information is generated by compressing at least some of the plurality of double delta values.
14 . The apparatus of claim 9 , wherein the first set of AP vicinity information comprises mean received signal strength for the AP at a plurality of locations.
15 . The apparatus of claim 9 , wherein the first set of AP vicinity information comprises mean round trip time for signal propagation between each grid point in the set of grid points and the AP.
16 . The apparatus of claim 9 , wherein the second set of AP vicinity information comprises a sequence of compressed values.
17 . A non-transitory processor-readable medium for providing access point (AP) vicinity information comprising processor-readable instructions configured to cause a processor to:
determine a first set of AP vicinity information for a set of grid points for a coverage area of an AP;
encode the first set of AP vicinity information based at least on a difference between AP vicinity information values for adjacent grid points to generate a second set of AP vicinity information; and
provide the second set of AP vicinity information to a mobile device.
18 . The non-transitory processor-readable medium of claim 17 , wherein the instructions are further configured to cause the processor to:
determine a plurality of delta values comprising differences between AP vicinity information values for adjacent grid points; and
compress at least some of the plurality of delta values to generate the second set of AP vicinity information.
19 . The non-transitory processor-readable medium of claim 18 , wherein the plurality of delta values are compressed based on two or more delta ranges.
20 . The non-transitory processor-readable medium of claim 19 , wherein the two or more delta ranges comprise a low-range, mid-range and high-range.
21 . The non-transitory processor-readable medium of claim 18 , wherein the instructions are further configured to cause the processor to:
determine a plurality of double delta values comprising differences between the plurality of delta values for adjacent grid points; and wherein the second set of AP vicinity information is generated by compressing at least some of the plurality of double delta values.
22 . The non-transitory processor-readable medium of claim 17 , wherein the first set of AP vicinity information comprises mean received signal strength for the AP at a plurality of locations.
23 . The non-transitory processor-readable medium of claim 17 , wherein the first set of AP vicinity information comprises mean round trip time for signal propagation between each grid point in the set of grid points and the AP.
24 . The non-transitory processor-readable medium of claim 17 , wherein the second set of AP vicinity information comprises a sequence of compressed values.
25 . A device comprising:
a non-transitory computer-readable medium;
a processor in communication with the non-transitory computer-readable medium, the processor configured to:
determine a first set of AP vicinity information for a set of grid points for a coverage area of an AP;
encode the first set of AP vicinity information based at least on a difference between AP vicinity information values for adjacent grid points to generate a second set of AP vicinity information; and
provide the second set of AP vicinity information to a mobile device.
26 . The device of claim 25 , wherein the processor is further configured to:
determine a plurality of delta values comprising differences between AP vicinity information values for adjacent grid points; and
compress at least some of the plurality of delta values to generate the second set of AP vicinity information.
27 . The device of claim 26 , wherein the plurality of delta values are compressed based on two or more delta ranges.
28 . The device of claim 27 , wherein the two or more delta ranges comprise a low-range, mid-range and high-range.
29 . The device of claim 26 , wherein the processor is further configured to:
determine a plurality of double delta values comprising differences between the plurality of delta values for adjacent grid points; and wherein the second set of AP vicinity information is generated by compressing at least some of the plurality of double delta values.
30 . The device of claim 25 , wherein the first set of AP vicinity information comprises mean received signal strength for the AP at a plurality of locations or mean round trip time for signal propagation between each grid point in the set of grid points and the AP.