Patent ID: 6356750
Filing Date: 2002-03-12
Classification: H04W

Abstract:
A method of identifying a TRAU frame in a mobile telephone system comprising: a network part and at least one subscriber terminal having a radio connection to the network part; the subscriber terminal normally transmitting to the network part a speech frame to be placed in the TRAU frame; and when discontinuous transmission is used, the subscriber terminal transmits to the network part a SID frame to be placed in the TRAU frame; and on the basis of the sum of the bits in a SID code word the TRAU frame is identified in the network part as a speech frame, a SID frame or a SID frame corrupted on the radio path, wherein by summing up, in addition to the SID code word bits, the other TRAU frame bits that normally contain speech, except for the SID parameter bits representing background noise.