(19)

(11)

EP 0 602 208 A1

(12)

(43) Date of publication: 22.06.1994 Bulletin 1994/25 (21) Application number: 93913415.0 (22) Date of filing: 23.06.1993

(51) International Patent Classification (IPC):  H04W 4/ 16( . ) H04W 60/ 00( . ) H04W 4/ 12( . ) (86) International application number: PCT/GB1993/001317 (87) International publication number: WO 1994/001976 (20.01.1994 Gazette 1994/03)

(84) Designated Contracting States: DE ES FR GB IT SE (30) Priority: 03.07.1992 GB 19920014186 (71) Applicant: GPT LIMITED Coventry, CV3 1HJ (GB)	(72) Inventors: STOWELL, David Frederick Leamington, Spa CV32 5XW (GB) RUSSEL-JONES, Peter Sandiacre, Nottingham NG10 5PJ (GB) CRISP, Graham Wollaton, Nottingham NG8 2SU (GB) (74) Representative: Branfield, Henry Anthony  The General Electric Company, p.l.c. GEC Patent Department Waterhouse Lane Chelmsford, Essex CM1 2QX Chelmsford, Essex CM1 2QX (GB)