An electrically scanned TACAN antenna comprising: a reflection plate; a monopole antenna provided on an upper surface of the reflection plate and configured to omnidirectionally radiate a signal; multiple parasitic radiators (130, 140) arranged around the monopole antenna and configured to operate as reflectors that reflect the signal or directors that direct the signal; and a controller configured to control the parasitic radiators (130, 140) operating as the reflectors to operate as the directors and some parasitic radiators (130, 140) among the parasitic radiators operating as the directors to operate as the reflectors at every predetermined timing and to choose the some parasitic radiators to be changed according to a preset sequence; wherein the parasitic radiators (130, 140) are circularly arranged at a predetermined distance from each other on donut-shaped first area and second area having concentricity with a location of the monopole antenna, and the second area is farther spaced from the monopole antenna than the first area; wherein in the first area there are sixteen of the multiple parasitic radiators arranged in each of two rows, and the parasitic radiators on the first area have different lengths and different radiation patterns depending on the row in which the parasitic radiators are arranged; wherein in the second area there are sixty three of the multiple parasitic radiators arranged in each of three rows, and the parasitic radiators on the second area have different lengths and different radiation patterns depending on the row in which the parasitic radiators are arranged; wherein the controller is configured to control parasitic radiators (131, 132, 133) arranged in one column and operating as the directors among the sixteen parasitic radiators arranged in each of the two rows to operate as the reflectors and to control a parasitic radiator arranged in any one row among the parasitic radiators arranged in the one column to operate in any one of two previously divided frequency bands within a preset frequency range for use of TACAN antenna; and wherein the controller is configured to control parasitic radiators (141, 142, 143) arranged in nine columns and operating as the directors equally spaced from each other among the sixty three parasitic radiators arranged in each of the three rows to operate as the reflectors and to control parasitic radiators arranged in any one row among the parasitic radiators arranged in the nine columns to operate in any one of three previously divided frequency bands within a preset frequency range for use of TACAN antenna. a reflection plate; a monopole antenna provided on an upper surface of the reflection plate and configured to omnidirectionally radiate a signal; multiple parasitic radiators (130, 140) arranged around the monopole antenna and configured to operate as reflectors that reflect the signal or directors that direct the signal; and a controller configured to control the parasitic radiators (130, 140) operating as the reflectors to operate as the directors and some parasitic radiators (130, 140) among the parasitic radiators operating as the directors to operate as the reflectors at every predetermined timing and to choose the some parasitic radiators to be changed according to a preset sequence; wherein the parasitic radiators (130, 140) are circularly arranged at a predetermined distance from each other on donut-shaped first area and second area having concentricity with a location of the monopole antenna, and the second area is farther spaced from the monopole antenna than the first area; wherein in the first area there are sixteen of the multiple parasitic radiators arranged in each of two rows, and the parasitic radiators on the first area have different lengths and different radiation patterns depending on the row in which the parasitic radiators are arranged; wherein in the second area there are sixty three of the multiple parasitic radiators arranged in each of three rows, and the parasitic radiators on the second area have different lengths and different radiation patterns depending on the row in which the parasitic radiators are arranged; wherein the controller is configured to control parasitic radiators (131, 132, 133) arranged in one column and operating as the directors among the sixteen parasitic radiators arranged in each of the two rows to operate as the reflectors and to control a parasitic radiator arranged in any one row among the parasitic radiators arranged in the one column to operate in any one of two previously divided frequency bands within a preset frequency range for use of TACAN antenna; and wherein the controller is configured to control parasitic radiators (141, 142, 143) arranged in nine columns and operating as the directors equally spaced from each other among the sixty three parasitic radiators arranged in each of the three rows to operate as the reflectors and to control parasitic radiators arranged in any one row among the parasitic radiators arranged in the nine columns to operate in any one of three previously divided frequency bands within a preset frequency range for use of TACAN antenna.