gmsk_sig.m

来自「MATLAB 程序设计教程 对初学者很容易上手 内有实例 讲解」· M 代码 · 共 42 行

function [s,no] = gmsk_sig(b,Ts,M,no);

%++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
%	Filename:	gmsk_sig.m
%
%	Function call:		input => [b,Ts,M,no]
%				output => [s,no]
%
%	Description:		1) Compute the phase by integrating b(k)
%				2) Generate complex envelope
%
%	Input:		b - Gaussian filter pulses 
%			Ts - sample time
%			M - no. of samples per bit
%
%	Output:	s - complex envelope
%
%	local var:	h - modulation index (0.5)
%			Intgral - cumulative sum 
%
% Author    : Jeff Laster, MPRG, Virginia Tech 
%+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
h = 0.5;			% Modulation Index

b=b/max(b);			% normalized max(b) = 1

Phase = pi*h*Ts*cumsum(b)';	% performs integration

s = exp(j*(Phase));		% Complex Envelope:  signal = Real( s(t)e^jwt )

%figure(no);
%total_sp(s,M,1024);
%no = no + 1;

%figure(no);
%subplot(1,1,1),plot(Phase);
%title(' GMSK Phase Diagram  w/ Respected to Carrier')
%xlabel(' T = 20 pts')
%grid
%no = no + 1;