Radio wave arrival direction estimation device, radio wave arrival direction estimation method, and radio wave arrival direction estimation program
A radio wave arrival direction estimation device according to an embodiment includes an antenna angle acquisition unit that acquires each of antenna angles indicating a plurality of different directions in which antennas having non-uniform antenna patterns are sequentially directed, a reception intensity measurement unit that measures reception intensities at which the antenna has received a radio wave at each of the antenna angles acquired by the antenna angle acquisition unit, a matching degree Calculation unit that calculates a matching degree between the antenna angle acquired by the antenna angle acquisition unit and the reception intensity measured by the reception intensity measurement unit, and an antenna pattern of the antenna for each antenna angle acquired by the antenna angle acquisition unit, and an estimation unit that estimates an antenna angle at which the matching degree Calculated by the matching degree Calculation unit is the maximum as an arrival direction of the radio wave.
1 . A radio wave arrival direction estimation device comprising one or more processors configured to perform operations comprising:
controlling a rotation drive to rotate an antenna having a non-uniform antenna pattern to sequentially direct the antenna in a plurality of different directions, and acquiring each of antenna angles indicating the plurality of different directions in which the antenna is sequentially directed;
measuring reception intensities at which the antenna has received a radio wave at each of the acquired antenna angles during the rotation;
calculating a matching degree between the acquired antenna angle and the measured reception intensity and an antenna pattern of the antenna for each acquired antenna angle, wherein the calculating comprises:
obtaining a difference between the reception intensity measured at each of the acquired antenna angles and a gain of the antenna pattern corresponding to the acquired antenna angle,
aggregating the differences to determine a total difference value for each acquired antenna angle, and
computing the matching degree based on the total difference value for each acquired antenna angle; and
estimating an antenna angle at which the calculated matching degree is the maximum, corresponding to where the calculated total difference value is the minimum, as an arrival direction of the radio wave.
2 . The radio wave arrival direction estimation device according to claim 1 , wherein the operations further comprise:
separating a component of an incoming wave or a delayed wave from the measured reception intensity, wherein,
during calculating the matching degree,
a matching degree between the acquired antenna angle and the separated reception intensity of the incoming wave or delayed wave, and an antenna pattern of the antenna is calculated for each acquired antenna angle.
3 . The radio wave arrival direction estimation device according to claim 2 , wherein
during separating the component of the incoming wave or the delayed wave from the measured reception intensity,
each incoming wave or delayed wave with the same propagation time from a transmitting station is separated based on a correlation with an existing pattern transmitted by a transmitting station.
4 . A radio wave arrival direction estimation method comprising:
controlling a rotation drive to rotate an antenna having a non-uniform antenna pattern to sequentially direct the antenna in a plurality of different directions, and acquiring each of antenna angles indicating the plurality of different directions in which the antenna is sequentially directed;
measuring reception intensities at which the antenna has received a radio wave at each of the acquired antenna angles during the rotation;
calculating a matching degree between the acquired antenna angle and the measured reception intensity and an antenna pattern of the antenna for each acquired antenna angle, wherein the calculating comprises:
obtaining a difference between the reception intensity measured at each of the acquired antenna angles and a gain of the antenna pattern corresponding to the acquired antenna angle,
aggregating the differences to determine a total difference value for each acquired antenna angle, and
computing the matching degree based on the total difference value for each acquired antenna angle; and
estimating an antenna angle at which the calculated matching degree is the maximum, corresponding to where the calculated total difference value is the minimum, as an arrival direction of the radio wave.
5 . The radio wave arrival direction estimation method according to claim 4 , further comprising:
separating a component of an incoming wave or a delayed wave from the measured reception intensity, wherein,
during calculating the matching degree,
a matching degree between the acquired antenna angle and the separated reception intensity of the incoming wave or delayed wave, and an antenna pattern of the antenna is calculated for each acquired antenna angle.
6 . The radio wave arrival direction estimation method according to claim 5 , wherein,
during separating the component of the incoming wave or the delayed wave from the measured reception intensity,
each incoming wave or delayed wave with the same propagation time from a transmitting station is separated based on a correlation with an existing pattern transmitted by a transmitting station.
7 . A non-transitory computer-readable storage medium storing a radio wave arrival direction estimation program for enabling a computer to perform operations comprising:
controlling a rotation drive to rotate an antenna having a non-uniform antenna pattern to sequentially direct the antenna in a plurality of different directions, and acquiring each of antenna angles indicating the plurality of different directions in which the antenna is sequentially directed;
measuring reception intensities at which the antenna has received a radio wave at each of the acquired antenna angles during the rotation;
calculating a matching degree between the acquired antenna angle and the measured reception intensity and an antenna pattern of the antenna for each acquired antenna angle, wherein the calculating comprises:
obtaining a difference between the reception intensity measured at each of the acquired antenna angles and a gain of the antenna pattern corresponding to the acquired antenna angle,
aggregating the differences to determine a total difference value for each acquired antenna angle, and
computing the matching degree based on the total difference value for each acquired antenna angle; and
estimating an antenna angle at which the calculated matching degree is the maximum, corresponding to where the calculated total difference value is the minimum, as an arrival direction of the radio wave.
8 . The non-transitory computer-readable storage medium according to claim 7 , wherein the operations further comprise:
separating a component of an incoming wave or a delayed wave from the measured reception intensity, wherein,
during calculating the matching degree,
a matching degree between the acquired antenna angle and the separated reception intensity of the incoming wave or delayed wave, and an antenna pattern of the antenna is calculated for each acquired antenna angle.
9 . The non-transitory computer-readable storage medium according to claim 8 , wherein,
during separating the component of the incoming wave or the delayed wave from the measured reception intensity,
each incoming wave or delayed wave with the same propagation time from a transmitting station is separated based on a correlation with an existing pattern transmitted by a transmitting station.