| 摘要 |
PROBLEM TO BE SOLVED: To provide a circular array antenna in which the number of devices such as amplifiers can be reduced compared to a conventional antenna. SOLUTION: The circular array antenna has a matrix circuit operating as an eight-port FFT circuit. Eight ports of the input side or the output side of the matrix circuit are connected to antennas arranged on a circumference at substantially equal intervals. Of the opposite ports, n-pieces of ports are terminated, and signals having predetermined phase differences are supplied to the residual (8-n) pieces of ports (thereby controlling a radiation pattern). From a point of a practical view, n is preferably 2-5. Where n=4 in the circular array antenna having eight element antennas, the number of the amplifiers can be reduced in half, and the number of variable phase shifters can be reduced in half. For a power distributor, an eight distribution type is not necessary and a four distribution type may be used. This array antenna can enable reduction in the cost, size, weight and power consumption of the apparatus. COPYRIGHT: (C)2006,JPO&NCIPI
|
