通信工程實驗報告班級：___通信1班____學號：________姓名：華億超市實驗一FPGA實驗BDPSK調制解調器設計一、實驗目的⒈掌握BDPSK的調制和解調原理。⒉掌握倍頻和分頻的概念以及原理。⒊用VerilogHDL硬件描述語言建模時序邏輯電路，實現BDPSK基帶調制解調系統。實驗報告要求⒈調制器和解調器的外引腳圖和內部結構圖。（MicrosoftVisio中截圖）⒉調制器模塊和解調器模塊的VerilogHDL代碼及注釋。⒊功能仿真和時序仿真結果的波形。（ModelSim中截圖）⒋（選做）開發板驗證后的波形。（示波器上拍照）實驗結果BDPSK調制系統的結構圖。BDPSK調制器模塊的VerilogHDL代碼及注釋。分頻器：modulefre_div(clk,cp0);//分頻器inputclk;outputregcp0;parameterN=32;integeri=0;initialbegincp0<=0;endalways@(posedgeclk)beginif(i<N/2-1)i=i+1;elsebegini=0;cp0=~cp0;endendendmodule隨機碼序列產生器（m序列）：modulePN_Seq(clk,reset_n,dataout); inputclk; inputreset_n; outputdataout; reg[7:1]c; always@(posedgeclkornegedgereset_n) begin if(!reset_n)c<=7'b1001110; else begin c[7]<=c[6]; c[6]<=c[5]; c[5]<=c[4]; c[4]<=c[3];c[3]<=c[2]; c[2]<=c[1]; c[1]<=c[2]^c[3]^c[4]^c[7]; end end assigndataout=c[7]; endmodule差分編碼器：moduledif(clk,reset_n,in,out);inputclk;inputreset_n;inputin;outputout;reg[1:0]o;always@(posedgeclkornegedgereset_n) beginif(!reset_n) o<=1; else begin o<=in^o; end end assignout=o;endmodule控制器：moduleController(clk,reset_n,s,address,cp);inputclk;inputreset_n;inputcp;inputs;//相對碼output[4:0]address;reg[4:0]address_data;reg[4:0]count;regsign;always@(posedgecp)beginif(s==0)count<=5'b10000;elseif(s==1)count<=5'b00000; sign<=1;endalways@(posedgeclkornegedgereset_n)beginif(!reset_n) address_data<=5'b00000;elsebeginif(sign==1) begin address_data<=count; sign<=0; endaddress_data<=address_data+1'b1; if(address_data==32) address_data<=5'b00000;endend assignaddress=address_data;endmodule正弦波形查找表：moduleLookUpTable(clk,reset_n,address,dataout);//正弦載波采樣表 inputclk; inputreset_n; input[4:0]address; output[7:0]dataout; reg[7:0]LUT[0:31]; always@(posedgeclkornegedgereset_n) begin if(!reset_n) begin LUT[0]<=128;//用C編程計算出的查找表采樣值填在這里 LUT[1]<=152; LUT[2]<=176; LUT[3]<=198; LUT[4]<=218; LUT[5]<=234; LUT[6]<=245; LUT[7]<=253; LUT[8]<=255; LUT[9]<=253; LUT[10]<=245; LUT[11]<=234; LUT[12]<=218; LUT[13]<=198; LUT[14]<=176; LUT[15]<=152; LUT[16]<=128; LUT[17]<=103; LUT[18]<=79; LUT[19]<=57; LUT[20]<=37; LUT[21]<=22; LUT[22]<=10; LUT[23]<=2; LUT[24]<=0; LUT[25]<=2; LUT[26]<=10; LUT[27]<=22; LUT[28]<=37; LUT[29]<=57; LUT[30]<=79; LUT[31]<=103; end end assigndataout=LUT[address]; endmodule功能仿真和時序仿真結果的波形功能仿真：時序仿真：實驗二MATLAB實驗OFDM誤碼率仿真（AWGN）一、實驗目的：1、掌握OFDM的基本原理。2、掌握用Matlab搭建OFDM系統的基本方法3、用MATLAB進行OFDM系統在AWGN信道下誤碼率分析。二、實驗報告要求1.所有程序完整的源代碼（.m文件）以及注釋。2.仿真結果。對于所有的圖形結果（包括波形與仿真曲線等），將圖形保存成.tif或者.emf的格式并插入word文檔。三、實驗結果1、所有程序完整的源代碼（.m文件）以及注釋：%16QAM的調制函數function[complex_qam_data]=qam16(bitdata)%modulationof16QAM,modulatebitdatato16QAMcomplexsignalX1=reshape(bitdata,4,length(bitdata)/4)';d=1;%mindistanceofsymblefori=1:length(bitdata)/4;forj=1:4X1(i,j)=X1(i,j)*(2^(4-j));endsource(i,1)=1+sum(X1(i,:));%converttothenumber1to16endmapping=[-3*d3*d; -d3*d;d3*d; 3*d3*d; -3*dd; -dd; dd; 3*dd; -3*d-d; -d-d; d-d;3*d-d; -3*d-3*d; -d-3*d; d-3*d; 3*d-3*d];fori=1:length(bitdata)/4qam_data(i,:)=mapping(source(i),:);%datamappingendcomplex_qam_data=complex(qam_data(:,1),qam_data(:,2));%16QAM的解調函數。function[demodu_bit_symble]=demoduqam16(Rx_serial_complex_symbols)%將得到的串行16QAM數據解調成二進制比特流complex_symbols=reshape(Rx_serial_complex_symbols,length(Rx_serial_complex_symbols),1);d=1;mapping=[-3*d3*d; -d3*d;d3*d; 3*d3*d; -3*dd; -dd; dd; 3*dd; -3*d-d; -d-d; d-d;3*d-d; -3*d-3*d; -d-3*d; d-3*d; 3*d-3*d];complex_mapping=complex(mapping(:,1),mapping(:,2));fori=1:length(Rx_serial_complex_symbols);forj=1:16;metrics(j)=abs(complex_symbols(i,1)-complex_mapping(j,1));end[min_metricdecode_symble(i)]=min(metrics);%將離某星座點最近的值賦給decode_symble(i)enddecode_bit_symble=de2bi((decode_symble-1)','left-msb');demodu_bit_symble=reshape(decode_bit_symble',1,length(Rx_serial_complex_symbols)*4);%加窗函數function[rcosw]=rcoswindow(beta,Ts)%定義升余弦窗，其中beta為滾降系數，Ts為包含循環前綴的OFDM符號的長度,Ts為正偶數t=0:(1+beta)*Ts;rcosw=zeros(1,(1+beta)*Ts);fori=1:beta*Ts;rcosw(i)=0.5+0.5*cos(pi+t(i)*pi/(beta*Ts));endrcosw(beta*Ts+1:Ts)=1;forj=Ts+1:(1+beta)*Ts+1;rcosw(j-1)=0.5+0.5*cos((t(j)-Ts)*pi/(beta*Ts));endrcosw=rcosw';%變換為列向量%OFDM主程序clearall;closeall;carrier_count=200;%子載波數symbols_per_carrier=12;%每子載波含符號數bits_per_symbol=4;%每符號含比特數,16QAM調制IFFT_bin_length=512;%FFT點數PrefixRatio=1/4;%保護間隔與OFDM數據的比例1/6~1/4GI=PrefixRatio*IFFT_bin_length;%每一個OFDM符號添加的循環前綴長度為1/4*IFFT_bin_length即保護間隔長度為128beta=1/32;%窗函數滾降系數GIP=beta*(IFFT_bin_length+GI);%循環后綴的長度20SNR=15;%信噪比dB%==================================================%================信號產生===================================baseband_out_length=carrier_count*symbols_per_carrier*bits_per_symbol;%所輸入的比特數目carriers=(1:carrier_count)+(floor(IFFT_bin_length/4)-floor(carrier_count/2));%共軛對稱子載波映射復數數據對應的IFFT點坐標conjugate_carriers=IFFT_bin_length-carriers+2;%共軛對稱子載波映射共軛復數對應的IFFT點坐標baseband_out=round(rand(1,baseband_out_length));%輸出待調制的二進制比特流%==============16QAM調制====================================complex_carrier_matrix=qam16(baseband_out);%列向量complex_carrier_matrix=reshape(complex_carrier_matrix',carrier_count,symbols_per_carrier)';%symbols_per_carrier*carrier_count矩陣figure(1);plot(complex_carrier_matrix,'*r');%16QAM調制后星座圖title('16QAM調制后星座圖')axis([-4,4,-4,4]);gridon%=================IFFT===========================IFFT_modulation=zeros(symbols_per_carrier,IFFT_bin_length);%添0組成IFFT_bin_lengthIFFT運算IFFT_modulation(:,carriers)=complex_carrier_matrix;%未添加導頻信號，子載波映射在此處IFFT_modulation(:,conjugate_carriers)=conj(complex_carrier_matrix);%共軛復數映射%=================================================================signal_after_IFFT=ifft(IFFT_modulation,IFFT_bin_length,2);%OFDM調制即IFFT變換time_wave_matrix=signal_after_IFFT;%時域波形矩陣，行為每載波所含符號數，列ITTF點數，N個子載波映射在其內，每一行即為一個OFDM符號%=====================添加循環前綴與后綴============XX=zeros(symbols_per_carrier,IFFT_bin_length+GI+GIP);fork=1:symbols_per_carrier;fori=1:IFFT_bin_length;XX(k,i+GI)=signal_after_IFFT(k,i);endfori=1:GI;XX(k,i)=signal_after_IFFT(k,i+IFFT_bin_length-GI);%添加循環前綴endforj=1:GIP;XX(k,IFFT_bin_length+GI+j)=signal_after_IFFT(k,j);%添加循環后綴endendtime_wave_matrix_cp=XX;%添加了循環前綴與后綴的時域信號矩陣,此時一個OFDM符號長度為IFFT_bin_length+GI+GIP=660%==============OFDM符號加窗================================windowed_time_wave_matrix_cp=zeros(1,IFFT_bin_length+GI+GIP);fori=1:symbols_per_carrierwindowed_time_wave_matrix_cp(i,:)=real(time_wave_matrix_cp(i,:)).*rcoswindow(beta,IFFT_bin_length+GI)';%加窗升余弦窗end%========================生成發送信號，并串變換=====================windowed_Tx_data=zeros(1,symbols_per_carrier*(IFFT_bin_length+GI)+GIP);windowed_Tx_data(1:IFFT_bin_length+GI+GIP)=windowed_time_wave_matrix_cp(1,:);fori=1:symbols_per_carrier-1;windowed_Tx_data((IFFT_bin_length+GI)*i+1:(IFFT_bin_length+GI)*(i+1)+GIP)=windowed_time_wave_matrix_cp(i+1,:);%并串轉換，循環后綴與循環前綴相疊加end%=======================================================Tx_data=reshape(windowed_time_wave_matrix_cp',(symbols_per_carrier)*(IFFT_bin_length+GI+GIP),1)';%加窗后循環前綴與后綴不疊加的串行信號%=================================================================temp_time1=(symbols_per_carrier)*(IFFT_bin_length+GI+GIP);%加窗后循環前綴與后綴不疊加發送總位數figure(2)subplot(2,1,1);plot(0:temp_time1-1,Tx_data);%循環前綴與后綴不疊加發送的信號波形gridonylabel('Amplitude(volts)')xlabel('Time(samples)')title('循環前后綴不疊加的OFDMTimeSignal')temp_time2=symbols_per_carrier*(IFFT_bin_length+GI)+GIP;subplot(2,1,2);plot(0:temp_time2-1,windowed_Tx_data);%循環后綴與循環前綴相疊加發送信號波形gridonylabel('Amplitude(volts)')xlabel('Time(samples)')title('循環前后綴疊加的OFDMTimeSignal')%===============加窗的發送信號頻譜=================================symbols_per_average=ceil(symbols_per_carrier/5);%符號數的1/5，10行avg_temp_time=(IFFT_bin_length+GI+GIP)*symbols_per_average;%點數，10行數據，10個符號averages=floor(temp_time1/avg_temp_time);average_fft(1:avg_temp_time)=0;%分成5段fora=0:(averages-1)subset_ofdm=Tx_data(((a*avg_temp_time)+1):((a+1)*avg_temp_time));%利用循環前綴后綴未疊加的串行加窗信號計算頻譜subset_ofdm_f=abs(fft(subset_ofdm));%分段求頻譜average_fft=average_fft+(subset_ofdm_f/averages);%總共的數據分為5段，分段進行FFT，平均相加endaverage_fft_log=20*log10(average_fft);figure(3)subplot(2,1,2)plot((0:(avg_temp_time-1))/avg_temp_time,average_fft_log)%歸一化0/avg_temp_time:(avg_temp_time-1)/avg_temp_timeholdonplot(0:1/IFFT_bin_length:1,-35,'rd')gridonaxis([00.5-40max(average_fft_log)])ylabel('Magnitude(dB)')xlabel('NormalizedFrequency(0.5=fs/2)')title('加窗的發送信號頻譜')%====================添加噪聲=================================Tx_signal_power=var(windowed_Tx_data);%發送信號功率linear_SNR=10^(SNR/10);%線性信噪比noise_sigma=Tx_signal_power/linear_SNR;noise_scale_factor=sqrt(noise_sigma);%標準差sigmanoise=randn(1,((symbols_per_carrier)*(IFFT_bin_length+GI))+GIP)*noise_scale_factor;%產生正態分布噪聲序列Rx_data=windowed_Tx_data+noise;%接收到的信號加噪聲%=============接收信號串/并變換去除前綴與后綴==================Rx_data_matrix=zeros(symbols_per_carrier,IFFT_bin_length+GI+GIP);fori=1:symbols_per_carrier;Rx_data_matrix(i,:)=Rx_data(1,(i-1)*(IFFT_bin_length+GI)+1:i*(IFFT_bin_length+GI)+GIP);%串并變換endRx_data_complex_matrix=Rx_data_matrix(:,GI+1:IFFT_bin_length+GI);%去除循環前綴與循環后綴，得到有用信號矩陣%=========================================================%OFDM解碼16QAM解碼%=================FFT變換=================================Y1=fft(Rx_data_complex_matrix,IFFT_bin_length,2);%OFDM解碼即FFT變換Rx_carriers=Y1(:,carriers);%除去IFFT/FFT變換添加的0，選出映射的子載波Rx_phase=angle(Rx_carriers);%接收信號的相位Rx_mag=abs(Rx_carriers);%接收信號的幅度figure(4);polar(Rx_phase,Rx_mag,'bd');%極坐標坐標下畫出接收信號的星座圖title('極坐標下的接收信號的星座圖')%===========================================================[M,N]=pol2cart(Rx_phase,Rx_mag);Rx_complex_carrier_matrix=complex(M,N);figure(5);plot(Rx_complex_carrier_matrix,'*r');%XY坐標接收信號的星座圖title('XY坐標接收信號的星座圖')axis([-4,4,-4,4]);gridon%====================16qam解調=================================Rx_serial_complex_symbols=reshape(Rx_complex_carrier_matrix',size(Rx_complex_carrier_matrix,1)*size(Rx_complex_carrier_matrix,2),1)';Rx_decoded_binary_symbols=demoduqam16(Rx_serial_complex_symbols);%============================================================baseband_in=Rx_decoded_binary_symbols;figure(6);subplot(2,1,1);stem(baseband_out(1:100));title('輸出待調制的二進制比特流')subplot(2,1,2);stem(baseband_in(1:100));title('接收解調后的二進制比特流')%================誤碼率計算===============================bit_errors=find(baseband_in~=baseband_out);bit_error_count=size(bit_errors,2)ber=bit_error_count/baseband_out_length仿真結果誤碼率實驗三MATLAB實驗OFDM誤碼率仿真（衰落）一、實驗目的：1、了解瑞利信道產生的原因及其特征。2、用MATLAB進行OFDM系統在瑞利信道下誤碼率分析。二、實驗報告要求1.所有程序完整的源代碼（.m文件）以及注釋。2.仿真結果。對于所有的圖形結果（包括波形與仿真曲線等），將圖形保存成.tif或者.emf的格式并插入word文檔。三、實驗結果1.%16QAM的調制函數function[complex_qam_data]=qam16(bitdata)%modulationof16QAM,modulatebitdatato16QAMcomplexsignalX1=reshape(bitdata,4,length(bitdata)/4)';d=1;%mindistanceofsymblefori=1:length(bitdata)/4;forj=1:4X1(i,j)=X1(i,j)*(2^(4-j));endsource(i,1)=1+sum(X1(i,:));%converttothenumber1to16endmapping=[-3*d3*d; -d3*d;d3*d; 3*d3*d; -3*dd; -dd; dd; 3*dd; -3*d-d; -d-d; d-d;3*d-d; -3*d-3*d; -d-3*d; d-3*d; 3*d-3*d];fori=1:length(bitdata)/4qam_data(i,:)=mapping(source(i),:);%datamappingendcomplex_qam_data=complex(qam_data(:,1),qam_data(:,2));%16QAM的解調函數。function[demodu_bit_symble]=demoduqam16(Rx_serial_complex_symbols)%將得到的串行16QAM數據解調成二進制比特流complex_symbols=reshape(Rx_serial_complex_symbols,length(Rx_serial_complex_symbols),1);d=1;mapping=[-3*d3*d; -d3*d;d3*d; 3*d3*d; -3*dd; -dd; dd; 3*dd; -3*d-d; -d-d; d-d;3*d-d; -3*d-3*d; -d-3*d; d-3*d; 3*d-3*d];complex_mapping=complex(mapping(:,1),mapping(:,2));fori=1:length(Rx_serial_complex_symbols);forj=1:16;metrics(j)=abs(complex_symbols(i,1)-complex_mapping(j,1));end[min_metricdecode_symble(i)]=min(metrics);%將離某星座點最近的值賦給decode_symble(i)enddecode_bit_symble=de2bi((decode_symble-1)','left-msb');demodu_bit_symble=reshape(decode_bit_symble',1,length(Rx_serial_complex_symbols)*4);%加窗函數function[rcosw]=rcoswindow(beta,Ts)%定義升余弦窗，其中beta為滾降系數，Ts為包含循環前綴的OFDM符號的長度,Ts為正偶數t=0:(1+beta)*Ts;rcosw=zeros(1,(1+beta)*Ts);fori=1:beta*Ts;rcosw(i)=0.5+0.5*cos(pi+t(i)*pi/(beta*Ts));endrcosw(beta*Ts+1:Ts)=1;forj=Ts+1:(1+beta)*Ts+1;rcosw(j-1)=0.5+0.5*cos((t(j)-Ts)*pi/(beta*Ts));endrcosw=rcosw';%變換為列向量%瑞利信道模擬functionr=Ray1(fm,fc,baseband_out_length)f=1:2*fm-1;%通頻帶長度y=0.5./((1-((f-fm)/fm).^2).^(1/2))/pi;%多普勒功率譜(基帶)Sf=zeros(1,baseband_out_length);Sf1=y;%多普勒濾波器的頻響Sf(fc-fm+1:fc+fm-1)=y;%(把基帶映射到載波頻率)x1=randn(1,baseband_out_length);x2=randn(1,baseband_out_length);nc=ifft(fft(x1+i*x2).*sqrt(Sf));%同相分量x3=randn(1,baseband_out_length);x4=randn(1,baseband_out_length);ns=ifft(fft(x3+i*x4).*sqrt(Sf));%正交分量r0=(real(nc)+j*real(ns));%瑞利信號r=abs(r0);%瑞利信號幅值%OFDM主程序clearall;closeall;fm=450;fc=4500;carrier_count=200;%子載波數symbols_per_carrier=12;%每子載波含符號數bits_per_symbol=4;%每符號含比特數,16QAM調制IFFT_bin_length=512;%FFT點數PrefixRatio=1/4;%保護間隔與OFDM數據的比例1/6~1/4GI=PrefixRatio*IFFT_bin_length;%每一個OFDM符號添加的循環前綴長度為1/4*IFFT_bin_length即保護間隔長度為128beta=1/32;%窗函數滾降系數GIP=beta*(IFFT_bin_length+GI);%循環后綴的長度20SNR=15;%信噪比dB%==================================================%================信號產生===================================baseband_out_length=carrier_count*symbols_per_carrier*bits_per_symbol;%所輸入的比特數目carriers=(1:carrier_count)+(floor(IFFT_bin_length/4)-floor(carrier_count/2));%共軛對稱子載波映射復數數據對應的IFFT點坐標conjugate_carriers=IFFT_bin_length-carriers+2;%共軛對稱子載波映射共軛復數對應的IFFT點坐標baseband_out=round(rand(1,baseband_out_length));%輸出待調制的二進制比特流%==============16QAM調制====================================complex_carrier_matrix=qam16(baseband_out);%列向量complex_carrier_matrix=reshape(complex_carrier_matrix',carrier_count,symbols_per_carrier)';%symbols_per_carrier*carrier_count矩陣figure(1);plot(complex_carrier_matrix,'*r');%16QAM調制后星座圖title('16QAM調制后星座圖')axis([-4,4,-4,4]);gridon%=================IFFT===========================IFFT_modulation=zeros(symbols_per_carrier,IFFT_bin_length);%添0組成IFFT_bin_lengthIFFT運算IFFT_modulation(:,carriers)=complex_carrier_matrix;%未添加導頻信號，子載波映射在此處IFFT_modulation(:,conjugate_carriers)=conj(complex_carrier_matrix);%共軛復數映射%=================================================================signal_after_IFFT=ifft(IFFT_modulation,IFFT_bin_length,2);%OFDM調制即IFFT變換time_wave_matrix=signal_after_IFFT;%時域波形矩陣，行為每載波所含符號數，列ITTF點數，N個子載波映射在其內，每一行即為一個OFDM符號%=====================添加循環前綴與后綴============XX=zeros(symbols_per_carrier,IFFT_bin_length+GI+GIP);fork=1:symbols_per_carrier;fori=1:IFFT_bin_length;XX(k,i+GI)=signal_after_IFFT(k,i);endfori=1:GI;XX(k,i)=signal_after_IFFT(k,i+IFFT_bin_length-GI);%添加循環前綴endforj=1:GIP;XX(k,IFFT_bin_length+GI+j)=signal_after_IFFT(k,j);%添加循環后綴endendtime_wave_matrix_cp=XX;%添加了循環前綴與后綴的時域信號矩陣,此時一個OFDM符號長度為IFFT_bin_length+GI+GIP=660%==============OFDM符號加窗================================windowed_time_wave_matrix_cp=zeros(1,IFFT_bin_length+GI+GIP);fori=1:symbols_per_carrierwindowed_time_wave_matrix_cp(i,:)=real(time_wave_matrix_cp(i,:)).*rcoswindow(beta,IFFT_bin_length+GI)';%加窗升余弦窗end%========================生成發送信號，并串變換=====================windowed_Tx_data=zeros(1,symbols_per_carrier*(IFFT_bin_length+GI)+GIP);windowed_Tx_data(1:IFFT_bin_length+GI+GIP)=windowed_time_wave_matrix_cp(1,:);fori=1:symbols_per_carrier-1;windowed_Tx_data((IFFT_bin_length+GI)*i+1:(IFFT_bin_length+GI)*(i+1)+GIP)=windowed_time_wave_matrix_cp(i+1,:);%并串轉換，循環后綴與循環前綴相疊加end%=======================================================Tx_data=reshape(windowed_time_wave_matrix_cp',(symbols_per_carrier)*(IFFT_bin_length+GI+GIP),1)';%加窗后循環前綴與后綴不疊加的串行信號%=================================================================temp_time1=(symbols_per_carrier)*(IFFT_bin_length+GI+GIP);%加窗后循環前綴與后綴不疊加發送總位數figure(2)subplot(2,1,1);plot(0:temp_time1-1,Tx_data);%循環前綴與后綴不疊加發送的信號波形gridonylabel('Amplitude(volts)')xlabel('Time(samples)')title('循環前后綴不疊加的OFDMTimeSignal')temp_time2=symbols_per_carrier*(IFFT_bin_length+GI)+GIP;subplot(2,1,2);plot(0:temp_time2-1,windowed_Tx_data);%循環后綴與循環前綴相疊加發送信號波形gridonylabel('Amplitude(volts)')xlabel('Time(samples)')title('循環前后綴疊加的OFDMTimeSignal')%===============加窗的發送信號頻譜=================================symbols_per_average=ceil(symbols_per_carrier/5);%符號數的1/5，10行avg_temp_time=(IFFT_bin_length+GI+GIP)*symbols_per_average;%點數，10行數據，10個符號averages=floor(temp_time1/avg_temp_time);average_fft(1:avg_temp_time)=0;%分成5段fora=0:(averages-1)subset_ofdm=Tx_data(((a*avg_temp_time)+1):((a+1)*avg_temp_time));%利用循環前綴后綴未疊加的串行加窗信號計算頻譜subset_ofdm_f=abs(fft(subset_ofdm));%分段求頻譜average_fft=average_fft+(subset_ofdm_f/averages);%總共的數據分為5段，分段進行FFT，平均相加endaverage_fft_log=20*log10(average_fft);figure(3)subplot(2,1,2)plot((0:(avg_temp_time-1))/avg_temp_time,average_fft_log)%歸一化0/avg_temp_time:(avg_temp_time-1)/avg_temp_timeholdonplot(0:1/IFFT_bin_length:1,-35,'rd')gridonaxis([00.5-40max(average_fft_log)])ylabel('Magnitude(dB)')xlabel('NormalizedFrequency(0.5=fs/2)')title('加窗的發送信號頻譜')%====================瑞利信道=================================cd=length(windowed_Tx_data);t=1:cd;delay=[03171109173251];power=[0-1-9-10-15-20];y_in=[zeros(1,delay(6))windowed_Tx_data];Rx_data=zeros(1,cd);fori=1:6Rx_data+Ray1(fm,fc,cd);Rx_data=Rx_data+Ray1(fm,fc,cd).*y_in(delay(6)+1-delay(i):delay(6)+cd-delay(i))*10^(power(i)/20);end%=============接收信號串/并變換去除前綴與后綴==================Rx_data_matrix=zeros(symbols_per_carrier,IFFT_bin_length+GI+GIP);fori=1:symbols_per_carrier;Rx_data_matrix(i,:)=Rx_data(1,(i-1)*(IFFT_bin_length+GI)+1:i*(IFFT_bin_length+GI)+GIP);%串并變換endRx_data_complex_matrix=Rx_data_matrix(:,GI+1:IFFT_bin_length+GI);%去除循環前綴與循環后綴，得到有用信號矩陣%=========================================================%OFDM解碼16QAM解碼%=================FFT變換=================================Y1=fft(Rx_data_complex_matrix,IFFT_bin_length,2);%OFDM解碼即FFT變換Rx_carriers=Y1(:,carriers);%除去IFFT/FFT變換添加的0，選出映射的子載波Rx_phase=angle(Rx_carriers);%接收信號的相位Rx_mag=abs(Rx_carriers);%接收信號的幅度figure(4);polar(Rx_phase,Rx_mag,'bd');%極坐標坐標下畫出接收信號的星座圖title('極坐標下的接收信號的星座圖')%===========================================================[M,N]=pol2cart(Rx_phase,Rx_mag);Rx_complex_carrier_matrix=complex(M,N);figure(5);plot(Rx_complex_carrier_matrix,'*r');%XY坐標接收信號的星座圖title('XY坐標接收信號的星座圖')axis([-4,4,-4,4]);gridon%====================16qam解調=================================Rx_serial_complex_symbols=reshape(Rx_complex_carrier_matrix',size(Rx_complex_carrier_matrix,1)*size(Rx_complex_carrier_matrix,2),1)';Rx_decoded_binary_symbols=demoduqam16(Rx_serial_complex_symbols);%============================================================baseband_in=Rx_decoded_binary_symbols;figure(6);subplot(2,1,1);stem(baseband_out(1:100));title('輸出待調制的二進制比特流')subplot(2,1,2);stem(baseband_in(1:100));title('接收解調后的二進制比特流')%================誤碼率計算===============================bit_errors=find(baseband_in~=baseband_out);bit_error_count=size(bit_errors,2)ber=bit_error_count/baseband_out_length4、仿真結果實驗四MATLAB實驗多入多出（MIMO）系統接收端檢測一、實驗目的1.掌握MIMO系統信道模型2.掌握MIMO接收端檢測的算法原理3.掌握MIMO系統誤碼率仿真的過程與分析方法二、實驗要求1.所有程序完整的源代碼（.m文件）以及注釋。2.仿真結果。對于所有的圖形結果（包括波形與仿真曲線等），將圖形保存成.tif或者.emf的格式并插入word文檔。三、實驗結果1.所有程序完整的源代碼（.m文件）以及注釋。%ML-ZF-MMSE檢測算法比較%bpsk調制-瑞利衰落信道-2個發送端，2個接收端%%clcclearN=10^4;%發送的符號數目Eb_N0_dB=0:20;%信噪比范圍nTx=2;nRx=2;%%%MLforii=1:length(Eb_N0_dB)%發送端ip=rand(1,N)>0.5;%等概率產生0和1s=2*ip-1;%BPSK調制0->-1;1->0sMod=kron(s,ones(nRx,1));%sMod=reshape(sMod,[nRx,nTx,N/nTx]);%將矩陣轉換為[nRx,nTx,N/nTx]形式h=1/sqrt(2)*[randn(nRx,nTx,N/nTx)+j*randn(nRx,nTx,N/nTx)];%瑞利衰落信道n=1/sqrt(2)*[randn(nRx,N/nTx)+j*randn(nRx,N/nTx)];%0均值高斯白噪聲%加入噪聲后在信道中傳輸a=h.*sMod;%將兩個矩陣的第三維分別相乘b=sum(h.*sMod,2);%將第三維加為一列c=squeeze(sum(h.*sMod,2));%變換為2x10矩陣d=10^(-Eb_N0_dB(ii)/20)*n;%噪聲為2x10矩陣y=squeeze(sum(h.*sMod,2))+10^(-Eb_N0_dB(ii)/20)*n;%最大似然接收%----------------------------%當[s1s2]=[+1,+1]sHat1=[11]; sHat1=repmat(sHat1,[1,N/2]);sHat1Mod=kron(sHat1,ones(nRx,1)); sHat1Mod=reshape(sHat1Mod,[nRx,nTx,N/nTx]); %發送矩陣zHat1=squeeze(sum(h.*sHat1Mod,2));%接收矩陣%e=abs(y-zHat1);%取理論接收與實際接收的絕對值J11=sum(abs(y-zHat1),1);%將兩行加為一行%%%當[s1s2]=[+1,-1]sHat2=[1-1]; sHat2=repmat(sHat2,[1,N/2]);sHat2Mod=kron(sHat2,ones(nRx,1)); sHat2Mod=reshape(sHat2Mod,[nRx,nTx,N/nTx]); zHat2=squeeze(sum(h.*sHat2Mod,2));J10=sum(abs(y-zHat2),1);%%%當[s1s2]=[-1,+1]sHat3=[-11]; sHat3=repmat(sHat3,[1,N/2]);sHat3Mod=kron(sHat3,ones(nRx,1)); sHat3Mod=reshape(sHat3Mod,[nRx,nTx,N/nTx]); zHat3=squeeze(sum(h.*sHat3Mod,2));J01=sum(abs(y-zHat3),1);%%當[s1s2]=[-1,-1]sHat4=[-1-1]; sHat4=repmat(sHat4,[1,N/2]);sHat4Mod=kron(sHat4,ones(nRx,1)); sHat4Mod=reshape(sHat4Mod,[nRx,nTx,N/nTx]); zHat4=squeeze(sum(h.*sHat4Mod,2));J00=sum(abs(y-zHat4),1);%%%從四組數值中找出最小值jj，所在位置ddrVec=[J11;J10;J01;J00];[jjdd]=min(rVec,[],1);%%%mappingtheminimatobitsref=[11;10;01;00];ipHat=zeros(1,N);ipHat(1:2:end)=ref(dd,1);ipHat(2:2:end)=ref(dd,2);%%%統計錯誤f=find([ip-ipHat]);%發生錯誤所在位置nErrML(ii)=size(find([ip-ipHat]),2);%錯誤個數end%%%ZFforii=1:length(Eb_N0_dB)%發送端ip=rand(1,N)>0.5;%等概率生成0,1s=2*ip-1;%BPSK調制0->-1;1->0%a=ones(nRx,1)sMod=kron(s,ones(nRx,1));%sMod=reshape(sMod,[nRx,nTx,N/nTx]);%變換矩陣形式為[nRx,nTx,N/NTx]h=1/sqrt(2)*[randn(nRx,nTx,N/nTx)+j*randn(nRx,nTx,N/nTx)];%瑞利信道n=1/sqrt(2)*[randn(nRx,N/nTx)+j*randn(nRx,N/nTx)];%0均值高斯白噪聲%加入白噪聲后在信道中傳輸y=squeeze(sum(h.*sMod,2))+10^(-Eb_N0_dB(ii)/20)*n;%接收端%求偽逆矩陣G=inv(H^H*H)*H^H%H^H*H的矩陣維數為[nTxxnTx].即[2x2]%[2x2]矩陣的轉置為[ab;cd]=1/(ad-bc)[d-b;-ca]hCof=zeros(2,2,N/nTx);hCof(1,1,:)=sum(h(:,2,:).*conj(h(:,2,:)),1);%dhCof(2,2,:)=sum(h(:,1,:).*conj(h(:,1,:)),1);%ahCof(2,1,:)=-sum(h(:,2,:).*conj(h(:,1,:)),1);%chCof(1,2,:)=-sum(h(:,1,:).*conj(h(:,2,:)),1);%bhDen=((hCof(1,1,:).*hCof(2,2,:))-(hCof(1,2,:).*hCof(2,1,:)));%ad-bchDen=reshape(kron(reshape(hDen,1,N/nTx),ones(2,2)),2,2,N/nTx);%hInv=hCof./hDen;%inv(H^H*H)hMod=reshape(conj(h),nRx,N);%H^HyMod=kron(y,ones(1,2));%接收信號矩陣化yMod=sum(hMod.*yMod,1);%H^H*yyMod=kron(reshape(yMod,2,N/nTx),ones(1,2));%yHat=sum(reshape(hInv,2,N).*yMod,1);%inv(H^H*H)*H^H*y%接收端硬判決解碼ipHat=real(yHat)>0;%統計錯誤nErrZF(ii)=size(find([ip-ipHat]),2);end%%%MMSEforii=1:length(Eb_N0_dB)%發送端ip=rand(1,N)>0.5;s=2*ip-1;%BPSK調制0->-1;1->0sMod=kron(s,ones(nRx,1));%sMod=reshape(sMod,[nRx,nTx,N/nTx]);%[nRx,nTx,N/NTx]h=1/sqrt(2)*[randn(nRx,nTx,N/nTx)+j*randn(nRx,nTx,N/nTx)];n=1/sqrt(2)*[randn(nRx,N/nTx)+j*randn(nRx,N/nTx)];%加入高斯白噪聲后在信道中傳輸y=squeeze(sum(h.*sMod,2))+10^(-Eb_N0_dB(ii)/20)*n;%接收端%MMSEW=inv(H^H*H+sigma^2*I)*H^H%H^H*Hi的維數為[nTxxnTx].即[2x2]%[2x2]矩陣的逆[ab;cd]=1/(ad-bc)[d-b;-ca]hCof=zeros(2,2,N/nTx);hCof(1,1,:)=sum(h(:,2,:).*conj(h(:,2,:)),1)+10^(-Eb_N0_dB(ii)/10);%dhCof(2,2,:)=sum(h(:,1,:).*conj(h(:,1,:)),1)+10^(-Eb_N0_dB(ii)/10);%ahCof(2,1,:)=-sum(h(:,2,:).*conj(h(:,1,:)),1);%chCof(1,2,:)=-sum(h(:,1,:).*conj(h(:,2,:)),1);%bhDen=((hCof(1,1,:).*hCof(2,2,:))-(hCof(1,2,:).*hCof(2,1,:)));%ad-bchDen=reshape(kron(reshape(hDen,1,N/nTx),ones(2,2)),2,2,N/nTx);hInv=hCof./hDen;%inv(H^H*H)hMod=reshape(conj(h),nRx,N);%H^HyMod=kron(y,ones(1,2));yMod=sum(hMod.*yMod,1);%H^H*yyMod=kron(reshape(yMod,2,N/nTx),ones(1,2));yHat=sum(reshape(hInv,2,N).*yMod,1);%inv(H^H*H)*H^H*y%接收端ipHat=real(yHat)>0;%統計錯誤nErrMMSE(ii)=size(find([ip-ipHat]),2);end%%%無衰落bpsk調制forii=1:length(Eb_N0_dB)%Transmitterip=rand(1,N)>0.5;s=2*ip-1;n=1/sqrt(2)*[randn(1,N)+j*randn(1,N)];%Noiseadditiony=s+10^(-Eb_N0_dB(ii)/20)*n;%additivewhitegaussiannoise%receiver-harddecisiondecodingipHat=real(y)>0;%countingtheerrorsnErrBPSK(ii)=size(find([ip-ipHat]),2);end%%%比特錯誤率simBer1=nErrML/N;%仿真比特錯誤率simBer2=nErrZF/N;simBer3=nErrMMSE/N;%simBer4=nErrBPSK/N;EbN0Lin=10.^(Eb_N0_dB/10);%theoryBer_nRx1=0.5.*(1-1*(1+1./EbN0Lin).^(-0.5));%p=1/2-1/2*(1+1./EbN0Lin).^(-1/2);%theoryBerMRC_nRx2=p.^2.*(1+2*(1-p));theoryBerBPSK=0.5*erfc(sqrt(EbN0Lin));%bpsktheoreticalber0.5erfc（sqrt（r））%%%作圖closeallfigure%semilogy(Eb_N0_dB,theoryBer_nRx1,'bp-','LineWidth',2);%semilogy(Eb_N0_dB,theoryBerMRC_nRx2,'kd-','LineWidth',2);semilogy(Eb_N0_dB,simBer1,'*g-','LineWidth',2);%MLholdonsemilogy(Eb_N0_dB,simBer2,'oy-','LineWidth',2);%ZFsemilogy(Eb_N0_dB,simBer3,'+r-','LineWidth',2);%MMSE%semilogy(Eb_N0_dB,simBer4,'mx-','LineWidth',2);semilogy(Eb_N0_dB,theoryBerBPSK,'b.-','LineWidth',2);%BPSKaxis([02010^-5