how to generate periodic impulsive noise asynchroous with mains in matlab?

hello all! i am working on a project and i need to generate periodic impulsive noise asynchronous with mains for a plc channel, all i know is that the impulse noise amplitude follows an exponential distribution and the individual impulses follow a poisson arrival process for a narrow band plc, i came across this code and it is giving the impulse noise plot. my question is why use uniform RV instead of exponential distribution and is that impulse noise

N=10000;               %number of samples
x=rand(N,1);           %generating an uniform random variable
IAT=1000;
t=1;                   %reference time
iin=32;                %number of interferers
for ik = 1:51,
    for ii = t:IAT,
        in(ii) = imp((ii-t)/iin);       %imp() only works for zero index
        impamp(ii) = in(ii)*noiseq(ii)*10;
    end
    t = t+IAT;
end
clear noiseq
l1 =length(impamp);
noiseq = [impamp zeros(1,length(N)-l1)].';

my question is why use uniform RV instead of exponential distribution and is that impulse noise expression correct? the IAT is not looking like following the poisson arrival time, why is that? and are there any other implementations of impulse noise matlab code that are more understandable? i am new to matlab and i wish to know more! thanks in advance!!