Array antenna calibration apparatus and array antenna calibration method

Claim 2

An array antenna calibration apparatus comprising: supply means for simultaneously supplying original calibration signals to a plurality of adjacent antenna elements constituting an array antenna, respectively, the original calibration signals being orthogonal to one another among the antenna elements; phase and amplitude characteristic calculation means for obtaining phase and amplitude characteristics by calculating correlations between calibration signals, emitted from the antenna elements and received by the adjacent antenna elements, and the original calibration signals related to the received calibration signals; relative calibration factor calculation means for obtaining a relative calibration factor among all the antenna elements constituting the array antenna based on the phase and amplitude characteristics of the respective antenna elements obtained from said phase and amplitude characteristic calibration means; and calibration means for calibrating transmission signals to be supplied to the respective antenna elements based on the relative calibration factor.

Claim 3

The array antenna calibration apparatus according to claim 1 , wherein the antenna elements constituting the array antenna are classified into a first group and a second group, and the relative calibration factor calculation means comprises: first relative calibration factor calculation means for obtaining a relative calibration factor among all of the antenna elements belonging to the first group based on the phase and amplitude characteristics of all the antenna elements of the first group; second relative calibration factor calculation means for obtaining a relative calibration factor among all of the antenna elements belonging to the second group based on the phase and amplitude characteristics of all the antenna elements of the second group; third relative calibration factor calculation means for obtaining a relative calibration factor between the first group and the second group based on the phase and amplitude characteristics of one of the antenna elements belonging to the first group and the phase and amplitude characteristics of one of the antenna elements belonging to the second group; and fourth relative calibration factor calculation means for obtaining a relative calibration factor among all the antenna elements constituting the array antenna based on the relative calibration factor among all the antenna elements belonging to the first group, the relative calibration factor among all the antenna elements belonging to the second group, and the relative calibration factor between the first group and the second group.

Claim 4

The array antenna calibration apparatus according to claim 2 , comprising: synthesizing means for synthesizing the calibration signal received by one of the antenna elements belonging to the second group from one of the antenna elements belonging to the first group with the calibration signal received by the one antenna element belonging to the first group from the one antenna element belonging to the second group, and wherein the third relative calibration factor calculation means obtains the relative calibration factor between the first group and the second group based on the phase and amplitude characteristic obtained by the phase and amplitude characteristic calculation means based on the synthesized calibration signal.

Claim 5

An array antenna calibration method comprising: a supply step of supplying original calibration signals to a plurality of antenna elements constituting an array antenna, respectively, the original calibration signals being perpendicular to one another among the antenna elements; a phase and amplitude characteristic calculation step of obtaining phase and amplitude characteristics by calculating correlations between calibration signals, emitted from the antenna elements and received by the adjacent antenna elements, and the original calibration signals related to the received calibration signals; a relative calibration factor calculation step of obtaining a relative calibration factor among all the antenna elements constituting the array antenna based on phase and amplitude characteristics of the respective antenna elements; and a calibration step of calibrating transmission signals to be supplied to the respective antenna elements based on the relative calibration factor.

Claim 6

An array antenna calibration method comprising: a supply step of supplying original calibration signals to a plurality of antenna elements constituting an array antenna, respectively, the original calibration signals being perpendicular to one another among the antenna elements; a phase and amplitude characteristic calculation step of obtaining phase and amplitude characteristics by calculating correlations between calibration signals, emitted from the antenna elements and received by the adjacent antenna elements, and the original calibration signals related to the received calibration signals; a relative calibration factor calculation step of obtaining a relative calibration factor among all the antenna elements constituting the array antenna based on phase and amplitude characteristics of the respective antenna elements; and a calibration step of calibrating transmission signals to be supplied to the respective antenna elements based on the relative calibration factor.

Claim 7

The array antenna calibration method according to claim 4 , wherein the antenna elements constituting the array antenna are classified into a first group and a second group, and the relative calibration factor calculation step includes: a first relative calibration factor calculation step of obtaining a relative calibration factor among all of the antenna elements belonging to the first group based on the phase and amplitude characteristics of all the antenna elements of the first group; a second relative calibration factor calculation step of obtaining a relative calibration factor among all of the antenna elements belonging to the second group based on the phase and amplitude characteristics of all the antenna elements of the second group; a third relative calibration factor calculation step of obtaining a relative calibration factor between the first group and the second group based on the phase and amplitude characteristics of one of the antenna elements belonging to the first group and the phase and amplitude characteristics of one of the antenna elements belonging to the second group; and a fourth relative calibration factor calculation step of obtaining a relative calibration factor among all the antenna elements constituting the array antenna based on the relative calibration factor among all the antenna elements belonging to the first group, the relative calibration factor among all the antenna elements belonging to the second group, and the relative calibration factor between the first group and the second group.

Claim 8

The array antenna calibration method according to claim 5 , comprising: a synthesizing step of synthesizing the calibration signal, received by one of the antenna elements belonging to the second group from one of the antenna elements belonging to the first group, with the calibration signal received by the one antenna element belonging to the first group from the one antenna element belonging to the second group, and wherein in the third relative calibration factor calculation step, the relative calibration factor between the first group and the second group is obtained based on the phase and amplitude characteristic obtained in the phase and amplitude characteristic calculation step based on the synthesized calibration signal.