Acoustic communication system

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.

1 . A telecommunications apparatus operable to interact with an audio transmission, the apparatus comprising:
 a memory operable to store control data for causing the telecommunications apparatus to respond to the audio transmission;   a receiver operable to receive an acoustic signal of the audio transmission and for converting the received acoustic signal into a corresponding electrical signal;   a data processor, coupled to said acoustic signal receiver, and operable to process said electrical signal to recover data encoded within the audio of said audio transmission and to provide the recovered data to the telecommunications apparatus; and   a responder operable to respond to the data recovered from the audio transmission in accordance with the stored control data after a delay defined by stored timing data to synchronize the response with the audio transmission.   
   
   
       2 . A telecommunications apparatus according to  claim 1 , wherein said recovered data comprises said timing data. 
   
   
       3 . A telecommunications apparatus according to  claim 2 , wherein the timing data is transmitted separately from the control data. 
   
   
       4 . A telecommunications apparatus according to  claim 2 , wherein the timing data is transmitted simultaneously with the control data. 
   
   
       5 . A telecommunications apparatus according to  claim 1 , wherein the responder is operable to cause the telecommunications device to send a message to a predefined telecommunications address. 
   
   
       6 . A telecommunications apparatus according to  claim 1 , wherein said audio transmission is part of a radio transmission. 
   
   
       7 . A telecommunications apparatus according to  claim 1 , wherein said audio transmission is part of a television transmission. 
   
   
       8 . A telecommunications apparatus according to  claim 1 , wherein said control data is a computer program and wherein said responder is operable to execute the computer program at a time defined by the timing data. 
   
   
       9 . A telecommunications apparatus according to  claim 8 , wherein the timing data comprises time delay information and wherein the responder is operable to: i) determine the time delay information from recovered timing data; and ii) delay execution of the computer program by a period dependent upon the determined time delay information. 
   
   
       10 . A telecommunications apparatus according to  claim 1 , which is a portable telephone. 
   
   
       11 . A telecommunications apparatus according to  claim 10 , wherein said receiver comprises a microphone of the portable telephone. 
   
   
       12 . A method of interacting with an audio transmission using a telecommunications apparatus, the method comprising:
 storing, within the telecommunications apparatus, control data for causing the telecommunications apparatus to respond to the audio transmission;   receiving an acoustic signal of the audio transmission and converting the received acoustic signal into a corresponding electrical signal;   processing the electrical signal corresponding to the received acoustic signal to recover data encoded within the audio of said audio transmission and to provide the recovered data to the telecommunications apparatus; and   causing the telecommunications apparatus to respond to the data recovered from the audio transmission in accordance with the stored control data after a delay defined by stored timing data, to synchronize the response with the audio transmission.   
   
   
       13 . A method according to  claim 12 , wherein said recovered data comprises said timing data. 
   
   
       14 . A method according to  claim 13 , wherein the timing data is received separately from the control data. 
   
   
       15 . A method according to  claim 13 , wherein the timing data is received simultaneously with the control data. 
   
   
       16 . A method according to  claim 12 , wherein the causing step causes the telecommunications apparatus to send a message to a predefined telecommunications address. 
   
   
       17 . A method according to  claim 12 , wherein said audio transmission is part of a radio transmission. 
   
   
       18 . A method according to  claim 12 , wherein said audio transmission is part of a television transmission. 
   
   
       19 . A method according to  claim 12 , wherein said control data is a computer program and wherein said causing step causes the telecommunications apparatus to execute the computer program at a time defined by the timing data. 
   
   
       20 . A method according to  claim 19 , wherein the timing data comprises time delay information and wherein the causing step causes the telecommunications apparatus to: i) determine the time delay information from recovered timing data; and ii) delay execution of the computer program by a period dependent upon the determined time delay information. 
   
   
       21 . A method according to  claim 12 , performed by a portable telephone. 
   
   
       22 . A method according to  claim 21 , wherein said receiving step uses a microphone of the portable telephone to receive the acoustic signal.