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New answers tagged digital-communications

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Your question is pretty unclear, but here goes: What you are calling a binary input is the Modulating signal. The Carrier is the signal that is modulated. When you say binary input frequency, I think the concept to which you are trying to refer is Bandwidth. In a real system at RF frequencies, the carrier frequency has to be higher than the bandwidth of ...

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I think a very intuitive, simple way to look at it would be to consider the modulation envelope generated by the baud rate. That envelope will expand and compress from the Doppler in the same manner that the carrier wave does. Hence, it exhibits the same Doppler effect scaled down to the baud rate.

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You understand the basic operation of the phase detector. Reproducing some of the above, the detected phase error is: $$e_k = M \arctan\left(\frac{i_k}{q_k}\right) \mod{2\pi}$$ As you noted, for an ideal QPSK constellation at the input to the phase detector, $e_k = \pi$ for all possible symbol values. However, in the presence of phase error $\theta$, the ...

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It all works out because $[\mathbf{R}]_{1, i}$ is just a number. It is the number in row $1$ column $i$ of the matrix $\mathbf{R}$. So the product $[\mathbf{R}]_{1, i}\mathbf{s}_i$ returns a vector of length $N \times 1$. See the line after Equation 10.

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In different applications, this parameter has different value that results optimum output. How I can find optimum smf value? What do the docs say the smooth function does? Write that down mathematically. As for any mathematical problem: you'll set up a formula for the "error" you're making (or a formula for the "goodness" you're achieving), and then you ...

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Think of the RB as a subset of the OFDM channel set. That reduces the complexity of finding $N_\text{FFT}$ matrix decompositions of $N_\text{TX antennas}\cdot N_\text{RX antennas}$ matrices for each user to $N_\text{carriers in the individual RB}$ decompositions for each user, which might well be smaller, because at user-level, often a significant amount of ...

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