% Schemes A and B
% delay under Poisson Traffic

clear all
close all
G=4; %number of subchannels

M=2000; % total simulation slots 
J=32;   % number of users
simurange=20; % nuber of points of Traffic

BufSize = M; 
num_trial=20; % number of Monto-Carlo experiments
throughput1=zeros(1,simurange); % scheme B
throughput2=zeros(1,simurange);  % scheme A

for ss=1:num_trial
    ss
    
    % generate the traffic
    [Traffic,WorkLoad] = gen_traffic(M, J, simurange);
    
    for ii = 1:simurange
        sm_traffic = G*Traffic(:,:,ii); % Generate new traffic
        Loads = zeros(1,J); 
        
        flag=zeros(1,J);
        time_table=zeros(J,(M+J)*G);
        time_table1=zeros(J,(M+J)*G);
        time_table2=zeros(J,(M+J)*G);
        
        % positions of packets in time axix
        pos_pack=zeros(J,(M+J)*G);
        for nn=1:J
            temp=find(Traffic(nn,:,ii)>=1);
            for mm=1:G
                pos_pack(nn,mm:G:G*(length(temp)-1)+mm)=temp;
            end
        end
        count_pack1=0;
        count_pack2=0;
        flag_CTE=0;
        
        Relay =1;
        
        for t1 = 1:M
            newLoads = sm_traffic(:,t1)'; % new traffic
            Loads = Loads + newLoads; % new traffic added to buffer
            
            flag_CTE=max(0,flag_CTE-1);
            
            if  flag_CTE==0
                
                Trans=Loads>0;
                num_active=sum(Trans);
                active = find(Trans)';
                
                if   num_active>0 
                    
                    flag_CTE=num_active;
                    
                        % calculate the successful packets using ML
                        % equalizer
                        %[succ Raysucc]=allian(t1,HH,HA,active1,subch,ch,G,Relay,ML);
                        
                        % From extensive simulations, we have found the ML equalizer is
                        % very robust even under low to moderate SNR and high collision
                        % orders, i.e., it can successfully recover packets
                        % without errors
                        % in the following , for convenience, we assume the use of the ML
                        % to greatly save the simulation time
                        succ1 = num_active*G;
                        succ2 = num_active*G;

                    count_pack1=count_pack1+num_active*G;
                    count_pack2=count_pack2+num_active*G;

                    
                    ret_array = zeros(1,J);
                    ret_array(active)=G;
                    Loads = Loads - ret_array;
                    
                end
                
            end
            
        end
        
        if count_pack1>0
            throughput1(ii)=throughput1(ii)+count_pack1/M/G;
            throughput2(ii)=throughput2(ii)+count_pack2/M/G;

        end
        
        
    end
end
WorkLoad=[0:simurange-1]/simurange+0.01;
figure
hold on
plot(WorkLoad,throughput1/num_trial,'k-o','linewidth',2)
plot(WorkLoad,throughput2/num_trial,'k-*','linewidth',2)
legend('Scheme B','Scheme A')