(19)

(11)

EP 1 118 075 A1

(12)

(43) Date of publication: 25.07.2001 Bulletin 2001/30 (21) Application number: 99943120.8 (22) Date of filing: 03.09.1999

(51) International Patent Classification (IPC)7: G10K 11/178 (86) International application number: PCT/GB9902/920 (87) International publication number: WO 0014/722 (16.03.2000 Gazette 2000/11)

(84) Designated Contracting States: AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE Designated Extension States: AL LT LV MK RO SI (30) Priority: 04.09.1998 GB 9819413 (71) Applicant: ULTRA ELECTRONICS LIMITED Greenford,Middlesex UB6 8UA (GB)	(72) Inventor: ROSS, Colin, Fraser Great Shelford,Cambridge CB2 5AN (GB) (74) Representative: Hogg, Jeffery Keith et al Withers & Rogers,Goldings House,2 Hays Lane London SE1 2HW London SE1 2HW (GB)