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Well, basically it may be right - just one thing left forgotten:
The spectral efficiency relates to the information bits, therefore if the eye diagram describes a coded system, one has to know the code rate in order to calculate the spectral efficiency in this way.
If the system is uncoded, then...
Well no.
remember the eye diagram is simply a descriptive graphical view of the transmitted symbols through the channel. The calculate the BER you either need to demodulate the received samples y[0],y[1],.. yourself and compare the the given transmitted signal x[0],x[1],... (if you have it)...
if you want 6 bit/symbol you need a 64-QAM modulation not 16-QAM.
in MATLAB:
M= 64;
Nsymbols = 1000;
h = modem.qammod('M',M,'InputType','bit','SymbolOrder','gray');
bits = bits = round(rand(log2(M)*Nsymbols ,1));
x = modulate(h,bits);
for the Rayleigh channel your model would be
y = h*x + w...
Hi,
you don't need an input to plot the capacity according to this formula. You can plot the normalized capacity C/B [Bit/Sec/Hz]
which is C_norm = log2(1+SNR)
and all you have to do is set a vector of SNR values and plot this.
The spectral efficiency is defined as (information rate/bandwidth) [bit/sec/Hz]
you cannot calculate it from the eye diagram - the eye diagram simply shows you the progression of the transmitted symbols through time.
in maximal ratio combining (MRC), the post-processing SNR (after combining the gains of the antennas) is
pp_SNR = ||h||^2*SNR
where
||h||^2 = sum(|h_i|^2)
since in AWGN the channel gain |h| of each antenna is 1, then you get
pp_SNR = L*SNR
where L is the number of the antennas combined in MRC...
several comments -
1. first of all i see you randomize a channel vector for each block. that is relating to situation where you assume your channel
is either fast fading, or you have perfect interleaving. there's nothing wrong with it, just make sure this is what you assume.
2. why are...
Outage is defined as events where the receiver cannot fulfill the required performance. So first you have to decide what is considered outage events - for example, you can define BER = 10E-4 is the minimum BER your system can handle.
and all below it (i.e. BER = 10E-3) is a failure.
So, after...
if your fading is non-dispersive, you have flat fading rayleigh.
so
y[m] = h[m]*s[m] + w[m]
you just have to generate h as a complex gaussian vector, at the size of your symbols vector.
Hi,
So if I understand correctly, you mean that it doesn't matter what is the variance of the channel gain ?
I mean, two RV with the same probability and different average gain will effect the system the same way ?
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