Uncorrelated input to a DPCM system?

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In a Differential Pulse Code Modulation (DPCM) system, the prediction algorithm relies on the assumption of correlated input signals to minimize redundancy in sampled data. When faced with uncorrelated input, the prediction error leads to a situation where the predictor coefficients become zero, resulting in the prediction error equating to the input signal itself. This indicates that the DPCM system fails to effectively compress the signal, as no predictive advantage is gained. The physical implication of this scenario is that the system would essentially transmit the raw input without any compression, negating the benefits of using DPCM. Understanding this behavior is crucial for optimizing DPCM systems in practical applications.
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Hi

I have a question regarding an ACTUAL Differential Pulse Code Modulation system setup. The prediction algorithm is predicated upon the assumption that an input to it is a correlated signal, and the objective therefore is to reduce redundant information when it is sampled at rates higher than the Nyquist rate.

Now, the prediction error when a linear prediction filter of order P is used, is given by

e_{n} = x[n] - \sum_{i=1}^{P}p_{k}x[n-k]

But for an uncorrelated input, the discrete time Weiner Hopf equations degenerate to

R_{X,0}Ip = 0

where R_{X,0} = E[x[n]^2], I = diag(1, 1, \ldots, 1) and p = (p_{1}, p_{2}, \ldots, p_{P})^{T}.

For a nontrivial signal then, this just reduces to p = 0, which simply implies that the predictor coefficients are all zero. If this is the case, the prediction error is e_{n} = x[n].

My question is: What happens physically if such a situation arises?

TIA.

(PS--This isn't homework.)
 
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