Dear everyone,
My code is followed:
clear;
clear all;
k = 8; % The number of user in a small cell
% rayleigh fading
% Fs = 9600;
% Ts = 1/Fs;
% fdmax = 0;
% Delay=1e-6*[10.15];
% PowerdB=-2*ones(1,1);
% rayCh = rayleighchan(Ts,fdmax,Delay,PowerdB);
% r = abs(rayCh.PathGains);
% for i = 2:k
% rayCh = rayleighchan(Ts,fdmax,Delay,PowerdB);
% r = [r,abs(rayCh.PathGains)]; % The uplink and downlink channel power gains of user k
% end
r = ones(1,k);
%Simulation parameters
n = 0.3; % shared fraction, 0<=n<=1
N0 = -147; % noise power spectral density（dBm/Hz）
N0 = power(10,N0/10)/1000; % Converted to w/Hz
Wul = 1e3; Wdl = 1e3; % The uplink and downlink bandwidth (Hz)
Pumax = 100; Pdmax = 1000; % The uplink and downlink power（w）
FC = 10^10; % The cloudlet server processing capacity（CPU cycles/s）
luk = 1.78*10^-6; % The amount of energy spent by the mobile device to extract each bit of offloaded data from the video source（J/bit）
ldk = 0.625; % Parameter that captures the mobile receiving energy expenditure per second in the downlink（J/s）
BIk = 1e4*ones(1,k); % Input bits from each user k to the cloudlet in the uplink (1Mbits)
BOk = 1e4*ones(1,k); % Out bits from the cloudlet to each user k in the downlink (1Mbits)
Vk = 2640*BIk; % Processing the input BIk by executing Vk CPU cycles at the cloudlet (CPU cycles)
Vs = n*Vk; % Shared CPU cycles
BOs = n*BOk; % Shared output bits that delivered to all users
BIs = n*BIk; % Shared input bits that can be sent by any of the users
%Initialize the z = [Pul,Bls,f,Pdl,PdM,TuS,TdS]
Pulk0 = Pumax*rand(1,k); % The uplink power（w）of user k
%Pdlk0 = Pdmax/k*ones(1,k); % The downlink power（w）to user k
Pdlk0 = rand(1,k);
Pdlk0 = Pdlk0/(sum(Pdlk0))*Pdmax;
PdlM0 = Pdmax*rand(1,1); % Transmit power (w) for multicasting
%BIsk0 = BIs/k.*ones(1,k); % A fraction of BIsk bits of the BIs shared bits transmited by user k
BIsk0 = rand(1,k);
BIsk0 = BIsk0/sum(BIsk0).*BIs;
fk0 = rand(1,k);
fk0 = fk0/(sum(fk0));
fs0 = rand(1,1); % Fractions of the processing power FC assigned to run the Vk CPU cycles exclusively for user k and the VS shared CPU cycles
f0 = [fk0,fs0];
PU0 = r.*Pulk0; % The uplink power after rayleigh fading
Rulk0 = (Wul/k)*log2(1+PU0/(N0*Wul/k)); % Transmitting rate of user k in the uplink
PD0 = r.*Pdlk0; % The downlink power after rayleigh fading
Rdlk0 = (Wdl/k)*log2(1+PD0/(N0*Wdl/k)); % Transmitting rate to user k in the downlink
PM0 = r.*PdlM0; % Multicasting power after rayleigh fading
RdlMk0 = Wdl*log2(1+PM0/(N0*Wdl)); % Transmitting rate to users for multicasting
TuS0 = max(BIsk0./Rulk0); % The time to complete the shared uplink transmissions (s)
TdS0 = max(BOs./RdlMk0); % The downlink transmission time to multicast BOs bits
Tmax = 10; % Maximum latency constraint（0.15s/0.05s）
z0 = [Pulk0,BIsk0,f0,Pdlk0,PdlM0,TuS0,TdS0];
alpha = 10^-5; epsilong = 10^-5; delta0 = rand; % Accuracy parameters
cvx_solver SeDuMi
cvx_begin
variables Pulk(1,k) BIsk(1,k) fk(1,k) fs Pdlk(1,k) PdlM TuS TdS;
f = [fk,fs];
PU = r.*Pulk;
Rulk = (Wul/k)*log(1+PU/(N0*Wul/k))/log(2);
PD = r.*Pdlk;
Rdlk = (Wdl/k)*log(1+PD/(N0*Wdl/k))/log(2);
PM = r.*PdlM;
RdlMk = Wdl*log(1+PM/(N0*Wdl))/log(2);
%The overall downlink mobile energy consumption for user k
Edlk = ((BOk-BOs).*inv_pos(Rdlk)+(BOs.*inv_pos(RdlMk)))*ldk;
%Mobile energy consumption of uplink transmission
z = [Pulk,BIsk,f,Pdlk,PdlM,TuS,TdS];
E = (z-z0)*diag(z0)*(z-z0)';
e1 = Pulk0.*(BIsk0+(BIk-BIsk0)).*inv_pos(Rulk);
e2 = Pulk0.*(BIsk+(BIk-BIsk0))./Rulk0;
e3 = Pulk.*(BIsk0+(BIk-BIsk0))./Rulk0;
e4 = luk*(BIsk+(BIk-BIsk0));
Eulk = e1+e2+e3+E+e4;
% Rewrite the latency constraints C.2
g1 = square_pos(BIsk+inv_pos(Rulk));
g2 = Rulk0.*Rulk0;
g3 = (g1-BIsk0.^2-1./g2);
g4 = BIsk0.*(BIsk-BIsk0);
g5 = (r.*Pulk0)/(N0*Wul/k);
g6 = (1+g5).*(Rulk0.^4);
g7 = g4-(Rulk0./g6).*(inv_pos(Rulk)-1./Rulk0);
gk = 1/2*g3-g7;
minimize(sum(Eulk+Edlk))
subject to
(BIk - BIsk0).*inv_pos(Rulk)+(Vk-Vs)/FC.*inv_pos(fk)+Vs/FC*inv_pos(fs)+(BOk-BOs).*inv_pos(Rdlk) <= Tmax-TuS-TdS; % Constraint C.1
gk <= TuS; % Constraint C.2
BOs.*inv_pos(RdlMk) <= TdS; % Constraint C.3
sum(fk) <= 1; % Constraint C.4
0 <= fk <= 1;
0 <= fs <= 1;
sum(BIsk) == BIs; % Constraint C.5
sum(Pdlk) <= Pdmax; % Constraint C.6
0 <= Pdlk <= Pdmax;
0 <= PdlM <= Pdmax;
0 <= Pulk <= Pumax;
0 <= TuS <= Tmax;
0 <= TdS <= Tmax;
0 <= BIsk <= BIs;
cvx_end
% Iteration
% while (norm(z-z0,2)^2) > epsilong
% delta = delta0*(1-alphadelta0);
% z1 = z0+delta(z-z0);
% z0 = z1;
% Pul0 = z1(1:k); Bls0 = z1(k+1:k+k); fk0 = z1(2k+1:3k); fs0 = z1(3k+1);
% Pdl0 = z1(3k+2:4k+1); PdM0 = z1(4k+2); TuS0 = z1(4k+3); TdS0 = z1(4k+4);
%
% cvx_begin
% variables Pulk(1,k) BIsk(1,k) fk(1,k) fs Pdlk(1,k) PdlM TuS TdS;
% f = [fk,fs];
% PU = r.Pulk;
% Rulk = (Wul/k)log(1+PU/(N0Wul/k))/log(2);
% PD = r.Pdlk;
% Rdlk = (Wdl/k)log(1+PD/(N0Wdl/k))/log(2);
% PM = r.PdlM;
% RdlMk = Wdllog(1+PM/(N0Wdl))/log(2);
% Edlk = ((BOk-BOs).inv_pos(Rdlk)+(BOs.inv_pos(RdlMk)))ldk;
%
% z = [Pulk,BIsk,f,Pdlk,PdlM,TuS,TdS];
% E = (z-z0)diag(z0)(z-z0)’;
% e1 = Pulk0.(BIsk0+(BIk-BIsk0)).inv_pos(Rulk);
% e2 = Pulk0.(BIsk+(BIk-BIsk0))./Rulk0;
% e3 = Pulk.(BIsk0+(BIk-BIsk0))./Rulk0;
% e4 = luk(BIsk+(BIk-BIsk0));
% Eulk = e1+e2+e3+E+e4;
%
% g1 = square_pos(BIsk+inv_pos(Rulk));
% g2 = Rulk0.Rulk0;
% g3 = (g1-BIsk0.^2-1./g2);
% g4 = BIsk0.(BIsk-BIsk0);
% g5 = (r.Pulk0)/(N0Wul/k);
% g6 = (1+g5).(Rulk0.^4);
% g7 = g4-(Rulk0./g6).(inv_pos(Rulk)-1./Rulk0);
% gk = 1/2g3-g7;
%
% minimize(sum(Eulk+Edlk))
% subject to
% (BIk - BIsk0).*inv_pos(Rulk)+(Vk-Vs)/FC.inv_pos(fk)+Vs/FCinv_pos(fs)+(BOk-BOs).*inv_pos(Rdlk) <= Tmax-TuS-TdS;
% gk <= TuS;
% BOs.*inv_pos(RdlMk) <= TdS;
% sum(fk) <= 1;
% 0 <= fk <= 1;
% 0 <= fs <= 1;
% sum(BIsk) == BIs;
% sum(Pdlk) <= Pdmax;
% 0 <= Pdlk <= Pdmax;
% 0 <= PdlM <= Pdmax;
% 0 <= Pulk <= Pumax;
% 0 <= TuS <= Tmax;
% 0 <= TdS <= Tmax;
% 0 <= BIsk <= BIs;
% cvx_end
% end
When I used different cvx_solver， I got different results.
How canI solve this problem to get the correct optimal value?
Thank you!
