clc;
clear;
close all;
warning off;
addpath(genpath(pwd));
MAX_RANK_CPE = 2; %rank per ms
TXP_BS = 47; % bs transmisison power in dbm
TXP_MS = 23; % ms transmisison power in dbm
NF_BS = 3; % bs noise figure in dB
NF_MS = 9; % ms noise figure in dB
N_RB = 50; % number of RBs in a carrier with 10MHz bandwidth
TONE_RB = 12; % number of tones per RB
N_TONE = N_RB*TONE_RB;
SC_F = 15e3; % subcarrier spacing
N_RBG = 8; % number of RBGs
TONE_RBG = 1; % number of tones per RBG modeled in this simulation
dl_txp_re = 10^((TXP_BS-30)/10)/N_TONE; % downlink transmission power per RE
ul_txp_re = 10^((TXP_MS-30)/10)/N_TONE; % uplink transmission power per RE
dl_np_re = 10^((-174+10*log10(SC_F)+NF_MS-30)/10); % downlink noise power per RE
ul_np_re = 10^((-174+10*log10(SC_F)+NF_BS-30)/10); % uplink noise power per RE
% input file
load('.\antenna_64x4_70ue.mat');
% output file
for i=1:length(linkInfo)
linkInfo_cp(i).dh_f = linkInfo(i).dh_f; % freq domain DL channel matrices per RBG
linkInfo_cp(i).uh_f = permute(linkInfo(i).dh_f,[2 1 3]); % freq domain UL channel matrices
linkInfo(i).ul_txp_re = ul_txp_re;
linkInfo(i).dl_txp_re = dl_txp_re;
linkInfo(i).rate = [];
linkInfo(i).sinr_zf = []; % for zero forcing
linkInfo(i).sinr_intf_prob = []; % for BiT
end
N_RX_U = size(linkInfo_cp(1).uh_f,1); % uplink number of receive antennas
N_TX_U = size(linkInfo_cp(1).uh_f,2); % uplink number of transmit antennas
N_RX_D = size(linkInfo_cp(1).dh_f,1); % downlink number of receive antennas
N_TX_D = size(linkInfo_cp(1).dh_f,2); % downlink number of transmit antennas
%% per RBG simulation
for i_rbg=1:N_RBG
disp(['Processing RBG : ' num2str(i_rbg) '/' num2str(N_RBG)]);
idx_s = (i_rbg-1)*TONE_RBG+1;
idx_e = i_rbg*TONE_RBG;
for i=1:length(linkInfo)
linkInfo(i).dv_svd = [];
linkInfo(i).uv_svd = [];
linkInfo(i).dh_f = linkInfo_cp(i).dh_f(:,:,idx_s:idx_e);
linkInfo(i).uh_f = linkInfo_cp(i).uh_f(:,:,idx_s:idx_e);
linkInfo(i).on = 1;
linkInfo(i).ri = MAX_RANK_CPE;
linkInfo(i).uv_tx = [];
end
%calculate SVD precoder for each served CPE
for i=1:length(linkInfo)
if linkInfo(i).servcell==1
cov_h = linkInfo(i).dh_f(:,:,1)'*linkInfo(i).dh_f(:,:,1);
for i_tone=2:TONE_RBG
cov_h = cov_h+linkInfo(i).dh_f(:,:,i_tone)'*linkInfo(i).dh_f(:,:,i_tone);
end
cov_h = cov_h/TONE_RBG;
[~,~,v] = svd(cov_h);
linkInfo(i).dv_svd = v(:,1:MAX_RANK_CPE); % downlink precoder based on SVD
cov_h = linkInfo(i).uh_f(:,:,1)'*linkInfo(i).uh_f(:,:,1);
for i_tone=2:TONE_RBG
cov_h = cov_h+linkInfo(i).uh_f(:,:,i_tone)'*linkInfo(i).uh_f(:,:,i_tone);
end
cov_h = cov_h/TONE_RBG;
[~,~,v] = svd(cov_h);
linkInfo(i).uv_svd = v(:,1:MAX_RANK_CPE); % uplink precoder based on SVD
end
end
%% uplink simulation: generate signal from served cpe
bs_info = [];
for i_c = 1:7 % 7 cell sites
for i_s=1:3 % 3 sectors per cell site
bs_info(i_c,i_s).h_cov_s = zeros(N_RX_U,N_RX_U);
idx_serv = find(([linkInfo(:).cell_ID]==i_c)&([linkInfo(:).sector_ID]==i_s)&([linkInfo(:).servcell]==1)&([linkInfo(:).on]==1)&([linkInfo(:).ri]>0));
if isempty(idx_serv); continue; end
for i_cpe=idx_serv % for each served cpe
tx_v = linkInfo(i_cpe).uv_svd(:,1:linkInfo(i_cpe).ri);
tx_v = tx_v/norm(tx_v,'fro')*sqrt(linkInfo(i_cpe).ul_txp_re);
linkInfo(i_cpe).uv_tx = tx_v;
eff_uhf = [];
for j=1:TONE_RBG
eff_uhf(:,:,j) = linkInfo(i_cpe).uh_f(:,:,j)*linkInfo(i_cpe).uv_tx; % uplink channel matrix x uplink precoder
bs_info(i_c,i_s).h_cov_s = bs_info(i_c,i_s).h_cov_s+eff_uhf(:,:,j)*eff_uhf(:,:,j)';
end
linkInfo(i_cpe).H_nb = eff_uhf;
end
end
end
%% uplink simulation: generate signal from interfering cpe
for i_c = 1:7
for i_s=1:3
bs_info(i_c,i_s).h_cov_i = zeros(N_RX_U,N_RX_U);
i_intf = find(([linkInfo(:).cell_ID]==i_c)&([linkInfo(:).sector_ID]==i_s)&([linkInfo(:).servcell]==0));
if isempty(i_intf); continue; end
for i_cpe=i_intf % for each interfering cpe
cpe_id = linkInfo(i_cpe).cpe_ID;
i_serv = find(([linkInfo(:).cpe_ID]==cpe_id)&([linkInfo(:).servcell]==1)&([linkInfo(:).on]==1)&([linkInfo(:).ri]>0));
if isempty(i_serv); continue; end
intf_eff_uhf = [];
for i=1:TONE_RBG
intf_eff_uhf(:,:,i) = linkInfo(i_cpe).uh_f(:,:,i)*linkInfo(i_serv).uv_tx; % uplink interfering channel matrix x uplink precoder
bs_info(i_c,i_s).h_cov_i = bs_info(i_c,i_s).h_cov_i+intf_eff_uhf(:,:,i)*intf_eff_uhf(:,:,i)';
end
end
bs_info(i_c,i_s).h_cov_s = bs_info(i_c,i_s).h_cov_s/TONE_RBG;
bs_info(i_c,i_s).h_cov_i = bs_info(i_c,i_s).h_cov_i/TONE_RBG;
bs_info(i_c,i_s).h_cov = bs_info(i_c,i_s).h_cov_s+bs_info(i_c,i_s).h_cov_i;
bs_info(i_c,i_s).h_cov = bs_info(i_c,i_s).h_cov+ul_np_re*eye(size(bs_info(i_c,i_s).h_cov)); % emulate uplink receive noise
h_cov_intf_prob = bs_info(i_c,i_s).h_cov;
idx_serv = find(([linkInfo(:).cell_ID]==i_c)&([linkInfo(:).sector_ID]==i_s)&([linkInfo(:).servcell]==1)&([linkInfo(:).on]==1)&([linkInfo(:).ri]>0));
if isempty(idx_serv); continue; end
%bit precoder
for i_cpe=idx_serv
linkInfo(i_cpe).v_bit = [];
for i=1:linkInfo(i_cpe).ri
linkInfo(i_cpe).v_bit(:,i) = inv(h_cov_intf_prob)*linkInfo(i_cpe).H_nb(:,i);
linkInfo(i_cpe).v_bit(:,i) = linkInfo(i_cpe).v_bit(:,i)/norm(linkInfo(i_cpe).v_bit(:,i))*sqrt(linkInfo(i_cpe).dl_txp_re/linkInfo(i_cpe).ri)/sqrt(length(idx_serv)); % equal power allocation per layer
linkInfo(i_cpe).v_bit(:,i) = conj(linkInfo(i_cpe).v_bit(:,i)); % conjugation needed for downlink transmission
end
end
end
end
%% downlink simulation: transmit with ZF precoder for ZF vs with BiT precoder for BiT; simulate the data rx at CPEs
%ZF precoder
for i_c = 1:7
for i_s=1:3
idx_serv = find(([linkInfo(:).cell_ID]==i_c)&([linkInfo(:).sector_ID]==i_s)&([linkInfo(:).servcell]==1)&([linkInfo(:).on]==1)&([linkInfo(:).ri]>0));
if isempty(idx_serv); continue; end
V = [];
for i_cpe=idx_serv
v = linkInfo(i_cpe).dv_svd(:,1:linkInfo(i_cpe).ri);
V = [V v];
end
V = V*inv(V'*V);
for i=1:size(V,2)
V(:,i) = V(:,i)/norm(V(:,i));
end
i_V = 1;
for i_cpe=idx_serv
linkInfo(i_cpe).v_zf = V(:,i_V:i_V+linkInfo(i_cpe).ri-1);
linkInfo(i_cpe).v_zf = linkInfo(i_cpe).v_zf/norm(linkInfo(i_cpe).v_zf,'fro')*sqrt(linkInfo(i_cpe).dl_txp_re)/sqrt(length(idx_serv));
i_V = i_V+linkInfo(i_cpe).ri;
end
end
end
%calcuate rate
for i_cpe=1:length(linkInfo)
if linkInfo(i_cpe).servcell==0 || linkInfo(i_cpe).on==0 || linkInfo(i_cpe).ri<=0; continue; end
cpe_id = linkInfo(i_cpe).cpe_ID;
%zf
r_cov = zeros(N_RX_D,N_RX_D,TONE_RBG);
for i_c = 1:7
for i_s=1:3
idx_serv = find(([linkInfo(:).cell_ID]==i_c)&([linkInfo(:).sector_ID]==i_s)&([linkInfo(:).servcell]==1)&([linkInfo(:).on]==1)&([linkInfo(:).ri]>0));
if isempty(idx_serv); continue; end
for i_serv=idx_serv
tx_v = linkInfo(i_serv).v_zf;
i_link = find(([linkInfo(:).cpe_ID]==cpe_id)&([linkInfo(:).cell_ID]==i_c)&([linkInfo(:).sector_ID]==i_s));
if isempty(i_link); continue; end
for i=1:TONE_RBG
for j=1:linkInfo(i_serv).ri
eff_dhf = linkInfo(i_link).dh_f(:,:,i)*tx_v(:,j);
r_cov
