gusucode.com > UWB_matlab源码程序 > CP0302/cp0302_PPM_periodic.m
% % FUNCTION 3.3 : "cp0302_PPM_periodic" % % Generation of a PPM-UWB signal in the case of a generic % periodic modulating signal and rectangular pulses % Modulating signal is chosen to be characterized by % an exponential decay exp(-t) % % Transmitted power is fixed at 'Pow' % The signal is sampled with frequency 'fc' % 'np' is the number of generated pulses % 'Ts' is the average pulse repetition period % Each rectangular pulse has time duration 'Tr' % The periodic signal is characterized by % shape parameters 'A' and 'B', and period 'Tp' % % The function returns the generated signal 'Stx' % and the corresponding sampling frequency 'fc' % % Programmed by Guerino Giancola % function [Stx,fc]=cp0302_PPM_periodic; % ---------------------------- % Step Zero - Input parameters % ---------------------------- Pow = -30; % average transmitted power (dBm) fc = 1e11; % sampling frequency np = 10000; % number of pulses Tr = 0.5e-9; % time duration of the rectangular pulse [s] Ts = 2e-9; % average pulse repetition period [s] A = 1e-9; % first shape parameter B = 10; % second shape parameter Tp = 20e-9; % period of the modulating signal [s] % ---------------------------------------- % Step One - Simulating transmission chain % ---------------------------------------- dt = 1 / fc; % sampling period sTs = floor(Ts/dt); % number of samples per frame sTot = sTs * np; % total number of samples Stx = zeros(1,sTot);% output vector % PPM j = (0:1:np-1); M0 = A.*exp(-(B/Tp).*mod(j*Ts,Tp)); M1 = j.*Ts; Mtot = M0 + M1; for k = 1 : np Stx(1+floor(Mtot(k)/dt))=1; end