(19)
(11) EP 1 914 834 A8

(12) CORRECTED EUROPEAN PATENT APPLICATION
Note: Bibliography reflects the latest situation

(15) Correction information:
Corrected version no 1 (W1 A2)

(48) Corrigendum issued on:
30.07.2008 Bulletin 2008/31

(88) Date of publication A3:
30.04.2008 Bulletin 2008/18

(43) Date of publication:
23.04.2008 Bulletin 2008/17

(21) Application number: 08000628.1

(22) Date of filing: 04.03.1998
(51) International Patent Classification (IPC): 
H01Q 3/24(2006.01)
G01S 13/44(2006.01)
 H01Q 3/26(2006.01)
(84) Designated Contracting States:
DE FR GB

(30) Priority: 18.08.1997 JP 22137297

(62) Application number of the earlier application in accordance with Art. 76 EPC:
98103806.0 / 0898174

(71) Applicant: FUJITSU LIMITED
Kawasaki-shi, Kanagawa 211-8588 (JP)

(72) Inventors:
  • Ninomiya, Teruhisa c/o Fujitsu Limited
    Kawasaki-shi, Kanagawa 211-8588 (JP)
  • Okubo, Naofumi c/o Fujitsu Limited
    Kawasaki-shi, Kanagawa 211-8588 (JP)

(74) Representative: HOFFMANN EITLE 
Patent- und Rechtsanwälte Arabellastrasse 4
81925 München
81925 München (DE)

 
Remarks:
This application was filed on 14-01-2008 as a divisional application to the application mentioned under INID code 62.
 


(54) Monopulse radar apparatus


(57) A monopulse radar apparatus has a single front (53) end shared by a pair of antennas (511,512), a first switch (52) for cyclically connecting the antennas to the front end (53) at a prescribed switching frequency, and a second switch (54) for cyclically connecting the output of the front end to frequency converters (571,512) corresponding to the antennas. The frequency converters frequency-convert intermediate-frequency signals of the respective antennas output by the front end to baseband signals at the switching frequency wherein the arrival direction of a reflected signals is estimated by comprising phases or amplitudes of output signals from said frequency converters.
In a second embodiment, the second switch and frequency converters are replaced by a pair of A/D converters acting is synchronism with the antenna selected by the first switch.