Questions tagged [capacity]
Capacity refers to the capability of a channel to transport data, typically measured in bits per channel usage.
29 questions
2 votes
0 answers
51 views
Can Bayesian methods explain probabilistic and geometric shaping for the multinomial channel?
Simpler case In a binomial channel, inputs $X= \left [ x_{1}, x_{2} \right ]$ represent probabilities of $\left [ {\rm failure}, {\rm success} \right ]$ in $n$ trials, with output $Y\in\left\{ 0, 1, \...
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0 votes
1 answer
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Where do single-bit shift errors commonly occur in real-world systems?
I'm interested in understanding the prevalence of single-bit shift errors—situations where a bit moves to an adjacent position without any insertion or deletion of bits—in practical systems. For ...
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1 vote
1 answer
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Hypergeometric functions in Wireless communication: Seeking guidance for Performance analysis
I am transitioning from pure mathematics to wireless communications and am particularly intrigued by the mathematical challenges in analyzing Nakagami-m fading channels. These channels are widely used ...
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1 vote
0 answers
55 views
"Best" energy efficiency via capacity of uncoded BPSK AWGN
I have numerically approximated the capacity of an uncoded, binary uniform input, real AWGN BPSK channel versus the SNR using mutual information and entropy, via Gauss-hermite quadrature. My task is ...
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0 votes
1 answer
44 views
What is the correct interpretation of the capacity formula with modulation?
Someone sent me the image below, and I think I'm confused as well. Is the second formula (modulation) correct? What does it mean? From the symbol, I think it represents capacity, but it doesn't make ...
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1 vote
0 answers
44 views
Applying Blahut-Arimoto Algorithm for AWGN Channels Capacity Calculation with Cost
I am exploring the Blahut-Arimoto algorithm (or any numerical method) for channel capacity calculations, particularly for continuous channels. I understand its application in discrete scenarios, but I ...
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0 votes
1 answer
124 views
OFDM system capacity if we double the subcarriers
Suppose we have two OFDM based systems A & B. System A has $N$ subcarriers and bandwidth $W$, and the number of samples in the CP is 10% of $N$. System B has $2N$ subcarriers, $2W$ bandwidth and ...
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1 vote
2 answers
2k views
What is the intuition explaining the Shannon-Hartley theorem?
In the digital domain, the signal to noise ratio (SNR) may be interpreted loosely but usefully as the number of discrete or quantized levels one can transmit reliably. For instance, loosely speaking, ...
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1 answer
120 views
Are there any techniques that can achieve higher transmission rate than Shannon capacity?
The maximum bit rate that can be transmitted over a channel with bandwidth B is determined by Shannon C=B log(1+S/N) Are there any techniques that could break this limit?
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1 answer
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Log-normal shadowing and mean power
Let's assume I'm receiving a signal with power measured in dBm shadowed according to the normal distribution, i.e. $P_{\text{dBm}} \sim N(0,1) $. If there is also a normally distributed noise power $...
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1 vote
2 answers
797 views
Rayleigh Fading
I am calculating the capacity of $K$ channels between a transmitter and $N$ receivers in a cellular scenario. I use the following equation: $$C_n^k = B\log_2\left(1 + \frac{Ph_n^k}{N_0B + I_n^k}\right)...
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448 views
Why are some Shannon's limit plots exponential rather than logarithmic?
This diagram again. This is clearly not the shape of $\log_2(1+SNR)$ but I very frequently see this instead of this: But this is also a stupid diagram because it doesn't cross at the origin. Also why ...
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2 votes
4 answers
2k views
Are capacity and spectral efficiency identical for a dicrete-time digital signal?
I saw this answer and saw on the wikipedia page that both spectral efficiency and capacity can be measured in bpcu i.e. 'bits/symbol'. I just want to confirm then that they are identical for a ...
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1 vote
1 answer
384 views
Difference: Ergodic channel capacity and spectral efficiency
Can someone explain what is the difference between the capacity and ergodic capacity? Ergodic capacity and spectral efficiency?
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1 vote
1 answer
115 views
Capacity and channel estimation algorithms: explanation of results
I study a spectral efficiency of a system with a precoding scheme with different channel schemes. Algorithm A for channel estimation gives a smaller estimation error instead of Algorithm B. I have ...
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