binary_exponential_baqkoff_csma_simul.m

MATSNL is a package of MATLAB M-files for computing wireless sensor node lifetime/power budget and s

clear;
% Unit time for random backoff
unit_backoff=1*(10^-3); % (1) msec

for h=1:10
max_backoff_num=2*h;
ch_idle_prob=0.3;
for u=1:20000
% Probability of Idle channel upon clear channel accessement

ch_busy_prob=1-platform.ch_idle_prob;
% Maximum number of random backoff for channel busy


A=2*(1-(2*ch_busy_prob)^max_backoff_num)...
    *(1-ch_busy_prob)/(1-2*ch_busy_prob)-(1-(ch_busy_prob)^max_backoff_num);
B=(ch_busy_prob^max_backoff_num)*(2^max_backoff_num-1);
avg_listen_delay=platform.unit_backoff*(A+B);

avg_listen_delay_simul=0;
len_backoff=0;
backoff_listen_energy=0;
Is_channel_IDLE=0;
m=1;
i=1;
while (Is_channel_IDLE==0)
     len_backoff=unit_backoff*uniform_gen(0,2^m);
len_backoff_log(i)=len_backoff;
i=i+1;

    avg_listen_delay_simul=avg_listen_delay_simul+len_backoff;

    Is_channel_IDLE=bern_gen(ch_idle_prob);
    
    m=m+1;
    if(m> max_backoff_num) 
        break;
    end

end

avg_listen_delay_simul=avg_listen_delay_simul;
    
avg_listen_delay_simul_log(u)=avg_listen_delay_simul;
% disp(['simul: ',num2str(platform.avg_listen_delay_simul)]);
% disp(['thy: ',num2str(platform.avg_listen_delay)]);

end
 disp(['simul: ',num2str(mean(avg_listen_delay_simul_log))]);
 disp(['thy: ',num2str(avg_listen_delay)]);
 
 mean_num_thy(h)=avg_listen_delay;
 mean_num(h)=mean(avg_listen_delay_simul_log);
A_log(h)=A;
end
plot(mean_num);hold on;
plot(mean_num_thy,'r');