| CPC H04B 11/00 (2013.01) [G10L 19/02 (2013.01)] | 20 Claims | 

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               1. A method comprising: 
            receiving data for transmission; 
                generating a first analog audio signal that encodes the data as phase differences according to a first protocol; and 
                transmitting, using a speaker, a first audio transmission containing the first analog audio signal. 
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