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(11)

EP 0 570 545 A1

(12)

(43) Date of publication: 24.11.1993 Bulletin 1993/47 (21) Application number: 92921761.0 (22) Date of filing: 13.10.1992

(51) International Patent Classification (IPC):  H04M 11/ 00( . ) H04Q 7/ 24( . ) H04Q 7/ 30( . ) H04Q 7/ 38( . ) H04Q 7/ 22( . ) H04Q 7/ 26( . ) H04Q 11/ 04( . ) (86) International application number: PCT/US1992/008674 (87) International publication number: WO 1993/011625 (10.06.1993 Gazette 1993/14)

(84) Designated Contracting States: DE FR GB IT (30) Priority: 06.12.1991 US 19910802933 (71) Applicant: MOTOROLA, INC. Schaumburg, IL 60196 (US)

(72) Inventors: TELL, Daniel, F. Deerfield, IL 60015 (US) ALDRICH, James, P. Glendale Heights, IL (US) MALCOLM, Richard, J. Carol Stream, IL 60188 (US) GUSTAFSON, Kenneth, A. Schaumburg, IL 60193 (US) LODWIG, John, P. Naperville, IL 60563 (US) (74) Representative: Dunlop, Hugh Christopher, et al  Motorola, European Intellectual Property, Midpoint, Alencon Link Basingstoke, Hampshire RG21 7PL Basingstoke, Hampshire RG21 7PL (GB)