Fingerprint data pre-process method for improving localization model

1. A computer-implemented method comprising:

acquiring a first plurality of pieces of observation data, each piece of observation data including a position of a mobile object and a received signal strength of a wireless signal, wherein the position is supplied by the mobile object and the received signal strength of the wireless signal is observed by the mobile object;

obtaining a time window set based on a delay amount of a change of the received signal strength that accompanies a movement of the mobile object, including setting a time span based on the received signal strength included in each of a second plurality of pieces of observation data;

correcting, for each observation timing of the received signal strength, each respective position of the mobile object included in each piece of observation data of the first plurality of pieces of observation data using at least one position of the mobile object within the time window;

calculating a prediction value of the received signal strength of the wireless signal for each of a second plurality of pieces of observation data, using a distance between a transmission apparatus and the position of the mobile object included in each of the second plurality of pieces of observation data acquired during the process of setting the time window;

correcting the prediction value to obtain a corrected prediction value using the prediction value within the time window; and

setting the time span as a time span for which a residual between the corrected prediction value and the received signal strength of the wireless signal included in each of the second plurality of pieces of observation data is at a minimum.

2. The computer-implemented method according to claim 1 , wherein the time span has a start point that is a time earlier than the observation timing.

3. The computer-implemented method according to claim 2 , wherein time span has an end point that is the observation timing.

4. The computer-implemented method according to claim 1 , wherein the correcting includes calculating the position of the mobile object included in each of the first plurality of pieces of observation data, using the position of the mobile object included in at least one piece of observation data observed at the observation timing within the time window, among the first plurality of pieces of observation data.

5. The computer-implemented method according to claim 4 , wherein the correcting includes correcting the position of the mobile object included in each of the first plurality of pieces of observation data to be an average of the positions of the mobile object included in at least one piece of observation data observed at the observation timing within the time window, among the first plurality of pieces of observation data.

6. The computer-implemented method according to claim 1 , further comprising: sending a request to move the mobile object relative to the transmission apparatus that transmits the wireless signal, during a process of setting the time window; and setting the time window based on the request.

7. The computer-implemented method according to claim 1 , further comprising: generating a received signal strength distribution in which a distribution of positions included in the first plurality of pieces of observation data has been made uniform, by extracting each piece of observation data corresponding to some positions from the first plurality of pieces of observation data for which the position of the mobile object has been corrected.

8. A computer program product for generating a received signal strength distribution, the computer program product comprising a computer readable storage medium having program instructions embodied therewith, the program instructions executable by a device to cause the device to perform operations comprising:

acquiring a first plurality of pieces of observation data, each piece of observation data including a position of a mobile object and a received signal strength of a wireless signal, wherein the position is supplied by the mobile object and the received signal strength of the wireless signal is observed by the mobile object;

obtaining a time window set based on a delay amount of a change of the received signal strength that accompanies a movement of the mobile object, including setting a time span based on the received signal strength included in each of a second plurality of pieces of observation data;

correcting, for each observation timing of the received signal strength, each respective position of the mobile object included in each piece of observation data of the first plurality of pieces of observation data using at least one position of the mobile object within the time window:

calculating a prediction value of the received signal strength of the wireless signal for each of a second plurality of pieces of observation data, using a distance between a transmission apparatus and the position of the mobile object included in each of the second plurality of pieces of observation data acquired during the process of setting the time window;

correcting the prediction value to obtain a corrected prediction value using the prediction value within the time window; and

setting the time span as a time span for which a residual between the corrected prediction value and the received signal strength of the wireless signal included in each of the second plurality of pieces of observation data is at a minimum.

9. The computer program product according to claim 8 , wherein the program instructions further cause the device to perform operations comprising: generating a received signal strength distribution in which a distribution of positions included in the first plurality of pieces of observation data has been made uniform, by extracting each piece of observation data corresponding to some positions from the first plurality of pieces of observation data for which the position of the mobile object has been corrected.

10. An apparatus comprising: at least one processor coupled to at least one computer readable storage medium having computer readable program instructions that when executed cause the at least one processor:

to acquire a first plurality of pieces of observation data, each piece of observation data including a position of a mobile object and a received signal strength of a wireless signal, wherein the position is supplied by the mobile object and the received signal strength of the wireless signal is observed by the mobile object;

to obtain a time window set based on a delay amount of a change of the received signal strength that accompanies a movement of the mobile object by setting a time span based on the received signal strength included in each of a second plurality of pieces of observation data;

to correct, for each observation timing of the received signal strength, each respective position of the mobile object included in each piece of observation data of the first plurality of pieces of observation data using at least one position of the mobile object within the time window time;

to calculate a prediction value of the received signal strength of the wireless signal for each of a second plurality of pieces of observation data, using a distance between a transmission apparatus and the position of the mobile object included in each of the second plurality of pieces of observation data acquired during the process of setting the time window;

to correct the prediction value to obtain a corrected prediction value using the prediction value within the time window: and

to set the time span as a time span for which a residual between the corrected prediction value and the received signal strength of the wireless signal included in each of the second plurality of pieces of observation data is at a minimum.

11. The apparatus according to claim 10 , wherein time span has a start point that is a predetermined time earlier than the observation timing and an end point that is the observation timing.

12. The apparatus according to claim 10 , wherein the at least one computer readable storage medium having computer readable program instructions that when executed cause the at least one processor to generate a received signal strength distribution in which a distribution of positions included in the first plurality of pieces of observation data has been made uniform, by extracting each piece of observation data corresponding to some positions from the first plurality of pieces of observation data for which the position of the mobile object has been corrected.