1 ber性能比較范本

1、1BER性能比較:%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%文件說明%函數(shù)說明：這是一個比較完整的OFDM系統(tǒng)，我在發(fā)送端做了比較簡單的QPSK調(diào)制映射生成OFDM符號，%經(jīng)串并轉(zhuǎn)換后插入導頻Pilot和循環(huán)前綴CP，再進行并串轉(zhuǎn)換加噪聲送入多徑瑞利信道。%在接收端，先進行串并轉(zhuǎn)換；然后去掉循環(huán)前綴

2、，提取導頻信息進行LS估計，最后經(jīng)過并串%轉(zhuǎn)換，QPSK解碼還原信息%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%參數(shù)說明%Ｘ：欲發(fā)送的二進制比特流%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

3、%%%%%%%%%%%%%%%clearallclcIFFT_bin_length=128%IFFT和FFT的點數(shù)128carrier_count=100%子載波個數(shù)100bits_per_symbol=2%每符號上的比特數(shù)2symbols_per_carrier=12%每楨的OFDM符號數(shù)12LI=7%導頻之間的間隔Np=ceil(carrier_countLI)1%導頻數(shù)加1使最后一列也是導頻，即有16個導頻子信道N_number=

4、carrier_countsymbols_per_carrierbits_per_symbol%總共發(fā)送的信息比特數(shù)%100122=2400carriers=1:carrier_countNpGI=8%保護間隔長度N_snr=40%每比特信息上的信噪比snr=8%信噪比間隔%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%發(fā)送端變量初始化X=zeros

5、(1N_number)%Ｘ：欲發(fā)送的二進制比特流X1=[]%原始的二進制數(shù)據(jù)流每2個一組進行QPSK映射編碼得到X1X2=[]%X1串并轉(zhuǎn)換后得到X2X3=[]%X2插入導頻后得到X3%以LI1=8為間隔，標注導頻子載波，即每8個子載波，第1個傳導頻，其余7個傳數(shù)據(jù)iflength(pilot)~=Nppilot=[pilotcarrier_countNp]end%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

6、%%%%%%%%%%%%%%%%%%%%%%%%%%%%%串并轉(zhuǎn)換X2=reshape(X1carrier_countsymbols_per_carrier).%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%插入導頻%%%

7、%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%signal=1:carrier_countNpsignal(pilot)=[]X3(:pilot)=training_symbols%在導頻子載波上填入導頻符號X3(:signal)=X2%在數(shù)據(jù)子載波上填入數(shù)據(jù)%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

8、%%%%%%%%%%%%%%%%%OFDM調(diào)制IFFT_modulation=zeros(symbols_per_carrierIFFT_bin_length)IFFT_modulation(:carriers)=X3X4=ifft(IFFT_modulationIFFT_bin_length2)%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

9、%%%%%%%%%%%加保護間隔（循環(huán)前綴）fk=1:symbols_per_carrierfi=1:IFFT_bin_lengthX6(kiGI)=X4(ki)endfi=1:GIX6(ki)=X4(kiIFFT_bin_lengthGI)%加CP：將每個符號最后的GI位復制到最前端endend%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%