lattewfdeclaration.zip_串口编程_多用户检测

% % Function 9.3 : "cp0901_MUIBER_2PPM" % % Evaluates the theoretical probability of error % for a 2PPM system in AWGN channels under the % Standard Gaussian Approximation % % 'ebno' is a vector containing the values in dB of the % ratio Eb/No % 'erx0' is the energy of the useful signal % 'erxMUI' is a vector containing the received energies % of the % interfering users. % 'pulse' is the waveform of the basic pulse % 'Rb' is the user bit rate [b/s] % 'PPMshift' is the value of the PPM shift [s] % 'fc' is the sampling time [Hz] % 'gamma_r' represents the ratio (Ts/(Tb/Ns)) % function [BER] = cp0901_MUIBER_2PPM(ebno,erx0,erxMUI,... pulse,Rb,PPMshift,fc,gamma_r) % ---------------------------------------------------- % Step One - Evaluation of the required constant terms % ---------------------------------------------------- % R0(epsilon) [R] dt = 1 / fc; % sampling period PPM_samples = floor(PPMshift/dt); pulse_samples = length(pulse); Ep = sum((pulse.^2).*dt); pulse = pulse./sqrt(Ep); % energy normalization p0 = zeros(1,PPM_samples+pulse_samples); p0(1:length(pulse)) = pulse; p1 = cp0804_signalshift(p0,fc,PPMshift); R = sum((p0.*p1).*dt); % (Sigma_m)^2 [sm2] sm2 = cp0901_sm2_PPM(pulse,PPMshift,fc); % MUI energy summation [EMUI] EMUI = sum(erxMUI./erx0); % ------------------------------------- % Step Two - Evaluation of SIR and SNRn % ------------------------------------- SIR = (((1-R)^2)*gamma_r)/(sm2*Rb*EMUI); EBN0 = 10.^(ebno/10); SNRn = EBN0.*(1-R); % ----------------------------------- % Step Three - Performance evaluation % ----------------------------------- SNRref = 1./((1./SNRn)+(1/SIR)); BER = 0.5.*erfc(sqrt(SNRref./2));