METHOD AND APPARATUS FOR SIGNAL-BASED POSITIONING
A method, apparatus, and computer program product are disclosed to normalize signal strengths and compensate for the variety of factors that may cause erroneous distance estimation, thereby increasing the accuracy of the distance estimation. In the context of a method, signal information is received relating to a signal transmitted by a first device and measured by a second device. Normalization information is accessed relating to the first device or the second device and normalized signal information is generated based on the signal information and the normalization information. A distance between the first device and the second device is estimated based on the normalized signal information. A corresponding apparatus and computer program product are also provided.
1 . A method comprising:
receiving signal information relating to a signal transmitted by a first device and measured by a second device;
accessing normalization information relating to the first device or the second device;
generating normalized signal information based on the signal information and the normalization information; and
estimating, by a processor, a distance between the first device and the second device based on the normalized signal information.
2 . The method of claim 1 , further comprising:
determining that the first device and the second device are suitably situated for positioning,
wherein the signal information is received after determining that the first device and the second device are available for positioning.
3 . The method of claim 2 , wherein determining that the first device and the second device are suitably situated for positioning comprises determining that the first device and the second device are recording video.
4 . The method of claim 1 , wherein the normalization information includes a signal strength pattern of the first device, a type of the first device, an orientation of the first device, signal reception properties of the second device, a type of the second device, an orientation of the second device, or sensor data.
5 . The method of claim 1 , further comprising:
determining estimated positions of the first device and the second device based on the estimated distance.
6 . The method of claim 5 , wherein the positions of the first device and the second device are determined using multi-dimensional scaling by majorizing a complicated function.
7 . The method of claim 5 , further comprising repeating the generating of normalized signal information, the estimating of the distance between the first device and the second device, and the determining estimated positions of the first device and the second device, wherein the normalized signal information is updated based on the estimated positions of the first device and the second device.
8 . An apparatus comprising at least one processor and at least one memory including computer program code, the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus to:
receive signal information relating to a signal transmitted by a first device and measured by a second device;
access normalization information relating to the first device or the second device;
generate normalized signal information based on the signal information and the normalization information; and
estimate a distance between the first device and the second device based on the normalized signal information.
9 . The apparatus of claim 8 , wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus to:
determine that the first device and the second device are suitably situated for positioning,
wherein the signal information is received after determining that the first device and the second device are suitably situated for positioning.
10 . The apparatus of claim 9 , wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus to determine that the first device and the second device are suitably situated for positioning by determining that the first device and the second device are recording video.
11 . The apparatus of claim 8 , wherein the normalization information includes a signal strength pattern of the first device, a type of the first device, an orientation of the first device, signal reception properties of the second device, a type of the second device, an orientation of the second device, or sensor data.
12 . The apparatus of claim 8 , wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus to:
determine estimated positions of the first device and the second device based on the estimated distance.
13 . The apparatus of claim 12 , wherein the positions of the first device and the second device are determined using multi-dimensional scaling by majorizing a complicated function.
14 . The apparatus of claim 12 , wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus to repeat the generating of normalized signal information, the estimating of the distance between the first device and the second device, and the determining estimated positions of the first device and the second device, wherein the normalized signal information is updated based on the estimated positions of the first device and the second device.
15 . A computer program product comprising at least one non-transitory computer-readable storage medium having computer-executable program code portions stored therein, the computer-executable program code portions comprising program code instructions that, when executed, cause an apparatus to:
receive signal information relating to a signal transmitted by a first device and measured by a second device;
access normalization information relating to the first device or the second device;
generate normalized signal information based on the signal information and the normalization information; and
estimate a distance between the first device and the second device based on the normalized signal information.
16 . The computer program product of claim 15 , wherein the program code instructions, when executed, further cause the apparatus to:
determine that the first device and the second device are suitably situated for positioning,
wherein the signal information is received after determining that the first device and the second device are suitably situated for positioning.
17 . The computer program product of claim 15 , wherein the normalization information includes a signal strength pattern of the first device, a type of the first device, an orientation of the first device, signal reception properties of the second device, a type of the second device, an orientation of the second device, or sensor data.
18 . The computer program product of claim 15 , wherein the program code instructions, when executed, further cause the apparatus to:
determine estimated positions of the first device and the second device based on the estimated distance.
19 . The computer program product of claim 18 , wherein the positions of the first device and the second device are determined using multi-dimensional scaling by majorizing a complicated function.
20 . The computer program product of claim 18 , wherein the program code instructions, when executed, further cause the apparatus to repeat the generating of normalized signal information, the estimating of the distance between the first device and the second device, and the determining estimated positions of the first device and the second device, wherein the normalized signal information is updated based on the estimated positions of the first device and the second device.