Abstract: There is described a communication system in which data is received by and/or transmitted to a telecommunications apparatus using an acoustic data channel. In embodiments, the data is encoded within the audio track of a media broadcast or other public broadcast. The invention has particular, but not exclusive, relevance to a cellular communication system. There are also described acoustic position detection systems for determining the position of a telecommunications apparatus.

Abstract: There is described a communication system in which data is received by and/or transmitted to a telecommunications apparatus using an acoustic data channel. In embodiments, the data is encoded within the audio track of a media broadcast or other public broadcast. The invention has particular, but not exclusive, relevance to a cellular communication system. There are also described acoustic position detection systems for determining the position of a telecommunications apparatus.

Abstract: There is described a communication system in which data is received by and/or transmitted to a telecommunications apparatus using an acoustic data channel. In embodiments, the data is encoded within the audio track of a media broadcast or other public broadcast. The invention has particular, but not exclusive, relevance to a cellular communication system. There are also described acoustic position detection systems for determining the position of a telecommunications apparatus.

Abstract: A number of encoders for encoding a data signal within an audio signal are provided. In some of the encoders, the audio signal is separated into a tonal part, and a residual part, and the data signal is shaped based on the residual part. In other encoders, the data signal is separated into a tonal part and a residual part, and the data signal is combined with the audio signal independence upon the residual part. In other encoders, the rate at which the data is encoded within the audio signal is varied in dependence upon the audio signal. There are also described various decoders associated with the described encoders.

Abstract: There is described a number of encoders for encoding a data signal within an audio signal. In some of the encoders, the audio signal is separated into a tonal part and a residual part, and the data signal is shaped based on the residual part. In other encoders, the data signal is separated into a tonal part and a residual part, and the data signal is combined with the audio signal independence upon the residual part. In other encoders, the rate at which the data is encoded within the audio signal is varied in dependence upon the audio signal. There are also described various decoders associated with the described encoders.

Abstract: There is described a communication system in which data is received by and/or transmitted to a telecomunications apparatus using an acoustic data channel. In embodiments, The data is encoded within the audio track of a media broadcast or other public broadcast. The invention has particular, but not exclusive, relevance to a cellular communication system. There are also described acoustic position detection systems for determining the position of a telecomunications apparatus.