Global Patent Index - EP 2178235 B1

EP 2178235 B1 20111005 - Encryption of information signals

Title (en)

Encryption of information signals

Title (de)

Verschlüsselung von Informationssignalen

Title (fr)

Cryptage de signaux d'information

Publication

EP 2178235 B1 20111005 (EN)

Application

EP 08390001 A 20081017

Priority

EP 08390001 A 20081017

Abstract (en)

[origin: EP2178235A1] The invention relates to techniques for encrypting and decrypting information signals, for example digital voice signals in mobile communications, based on polyphase filter banks. A method embodiment of the invention for encrypting information signals comprises the steps of splitting, based on multiple analysis subband filters, an input information signal into a set of signal subbands; performing an encryption operation on one or more subbands of the set of subbands; and synthesizing, based on multiple synthesis subband filters, the encrypted set of subbands into an output information signal, wherein a particular synthesis filter is the product of all analysis filters except the analysis filter corresponding in subband to the particular synthesis filter.

IPC 8 full level

H04K 1/04 (2006.01)

CPC (source: EP)

H04K 1/04 (2013.01)

Designated contracting state (EPC)

AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MT NL NO PL PT RO SE SI SK TR

DOCDB simple family (publication)

EP 2178235 A1 20100421; EP 2178235 B1 20111005; AT E527768 T1 20111015; CY 1112183 T1 20151209

DOCDB simple family (application)

EP 08390001 A 20081017; AT 08390001 T 20081017; CY 111101254 T 20111216