| 摘要 |
PROBLEM TO BE SOLVED: To provide a device that can fast, repeatedly and two-dimensionally image the estimation result of an incoming direction of radio waves and display the image so as to easily specify the radio wave emission source, even when the source is a cellular phone terminal that employs TDMA (time division multiple access) system. SOLUTION: Radio waves received by a reference antenna A0 and an array antenna A1 are converted into intermediate frequencies, that can be subjected to AD conversion by a frequency converting unit 30. An antenna-switching unit 20 sequentially switches the output of antenna elements from the array antenna A1 and simultaneously receives the output of the reference antenna A0. Radio waves simultaneously, received by the selected element of the array antenna A1 and the reference antenna A0, are digitized by an A/D conversion unit 40, are processed to estimate the incoming direction by an incoming direction estimating unit 60 by each time slot of a cellular phone terminal in an intermediate wave detecting unit 50, imaged two-dimensionally, and displayed in a display unit 70. COPYRIGHT: (C)2007,JPO&INPIT
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