I am trying to simulate indoor communications with all components included. But something disturbs me when it comes to Rayleigh fading part.
I am adding my rayleigh fading to the transmitted signal with that code:
rayleigh_h = 1/sqrt(2)*[randn(1, length(s_l) / OSR) + 1j * randn(1, length(s_l) / OSR)]; %Constructing rayleigh channel complex coefficients rayleigh_h = repelem(rayleigh_h, OSR); %Coefficient repeating to apply rayleigh fading to all samples s_l = s_l .* rayleigh_h;
s_l: the complex modulated signal
OSR: Over sampling ratio
If I need to clarify the code a bit: Every bit is being sampled by a number of samples named "Over sampling ratio". Since I want to add rayleigh fading symbol-by-symbol instead of sample-by-sample, all samples that belong to a symbol are multiplied by the rayleigh coefficient corresponding each bit.
Sorry for if the code clarification is a bit confusing.
Here is my real question.
The method I am using above obviously changing the amplitudes of the signal with multiplying the with complex gaussian coefficients at instants. However, at indoor locations, it is fairly correct to assume that mobility(speed) of the devices should be limited with the walking speed. Therefore changes with the signal, and the fading coefficients should change slowly, not that fast. I am trying to figure out how to simulate it.
Any help is appreciated. Please also advise me if I have misunderstood the concept of the rayleigh fading.