Distributed Joint Source-Channel Coding on a Multiple Access Channel with Side Information
R. Rajesh, Vinod Sharma
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49 pages, Technical Report, DRDO-IISc programme on Advanced Research in Mathematical Engineering, Dept of ECE, Indian Institute of Science, Bangalore, India
We consider the problem of transmission of several distributed sources over a multiple access channel (MAC) with side information at the sources and the decoder. Source-channel separation does not hold for this channel. Sufficient conditions are provided for transmission of sources with a given distortion. The source and/or the channel could have continuous alphabets (thus Gaussian sources and Gaussian MACs are special cases). Various previous results are obtained as special cases. We also provide several good joint source-channel coding schemes for a discrete/continuous source and discrete/continuous alphabet channel. Channels with feedback and fading are also considered.
Keywords: Multiple access channel, side information, lossy joint source-channel coding, channels with feedback, fading channels.
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A new universal coding/decoding scheme for random access with collision detection is given in the case of two senders. The result is used to give an achievable joint source-channel coding error exponent for multiple access channels in the case of independent sources. This exponent is improved in a modified model that admits error free 0 rate communication between the senders.
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Signature coding for multiple access OR channel is considered. We prove that in block asynchronous case the upper bound on the minimum code length asymptotically is the same as in the case of synchronous access.
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In this work, the problem of transmitting an i.i.d Gaussian source over an i.i.d Gaussian wiretap channel with an i.i.d Gaussian side information available at the intended receiver is considered. The intended receiver is assumed to have a certain minimum SNR and the eavesdropper is assumed to have a strictly lower SNR, compared to the intended receiver. The objective is to minimize the distortion of source reconstruction at the intended receiver. In this work, it is shown that the source-channel separation coding scheme is optimum in the sense of achieving minimum distortion. Two hybrid digita…
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