Hello, I am studying MSK modulation, does anyone know how to genrate a MSK signal in matlab, pls help me..Thanks. Gon.
MSK signal
Started by ●December 4, 2006
Reply by ●December 4, 20062006-12-04
ofdm wrote:> Hello, > > I am studying MSK modulation, does anyone know how to genrate a MSK signal > in matlab, pls help me..Thanks.Google "minimum-shift keying". Obce you know what it is, you'll probably know haw to generate it. If not, you'll learn Matlab trying. Jerry -- Engineering is the art of making what you want from things you can get. �����������������������������������������������������������������������
Reply by ●December 4, 20062006-12-04
"Jerry Avins" <jya@ieee.org> wrote in message news:weSdnXvfSdpQ9unYnZ2dnUVZ_s6dnZ2d@rcn.net...> ofdm wrote: > > Hello, > > > > I am studying MSK modulation, does anyone know how to genrate a MSKsignal> > in matlab, pls help me..Thanks. > > Google "minimum-shift keying". Obce you know what it is, you'll probably > know haw to generate it. If not, you'll learn Matlab trying. > > Jerry > -- > Engineering is the art of making what you want from things you can get. > ����] Not very helpful... ������������������������������������������������������������������� -- Posted via a free Usenet account from http://www.teranews.com
Reply by ●December 4, 20062006-12-04
Heid the baw - goal!! wrote: ...> Not very helpful...Was it you in another guise who asked for help? If not, how do you know? Jerry -- Engineering is the art of making what you want from things you can get. �����������������������������������������������������������������������
Reply by ●December 5, 20062006-12-05
Jerry Avins wrote:> ofdm wrote: > >> Hello, >> I am studying MSK modulation, does anyone know how to genrate a MSK >> signal >> in matlab, pls help me..Thanks. > > > Google "minimum-shift keying". Obce you know what it is, you'll probably > know haw to generate it. If not, you'll learn Matlab trying. > > JerryIt was Googling (well, AltaVista-ing) "minimum-shift keying" that led to me posting my Master's thesis on the web. Here it is again: http://www.wescottdesign.com/articles/MSK/mskTop.html. -- Tim Wescott Wescott Design Services http://www.wescottdesign.com Posting from Google? See http://cfaj.freeshell.org/google/ "Applied Control Theory for Embedded Systems" came out in April. See details at http://www.wescottdesign.com/actfes/actfes.html
Reply by ●December 5, 20062006-12-05
MATLAB communications blockset has MSK built in function that you can use. I totally agree with Jerry's response. No other better way to learn. :-) And hey, these days, Wikipedia is real rocking as far as communications and Random Process concepts are concerned. :-) My take. Tim Wescott wrote:> Jerry Avins wrote: > > > ofdm wrote: > > > >> Hello, > >> I am studying MSK modulation, does anyone know how to genrate a MSK > >> signal > >> in matlab, pls help me..Thanks. > > > > > > Google "minimum-shift keying". Obce you know what it is, you'll probably > > know haw to generate it. If not, you'll learn Matlab trying. > > > > Jerry > > It was Googling (well, AltaVista-ing) "minimum-shift keying" that led to > me posting my Master's thesis on the web. > > Here it is again: http://www.wescottdesign.com/articles/MSK/mskTop.html. > > -- > > Tim Wescott > Wescott Design Services > http://www.wescottdesign.com > > Posting from Google? See http://cfaj.freeshell.org/google/ > > "Applied Control Theory for Embedded Systems" came out in April. > See details at http://www.wescottdesign.com/actfes/actfes.html
Reply by ●December 5, 20062006-12-05
hi gon, i have this script written by matt wilbur (dowloaded) that returns the I and Q channels of MSK/GMSK modulated waveforms. hope it helps. -fahim %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% function [msk_phase,gmsk_phase,xi,xq,t] =gmsk(bits,Rb,ns,BT) % Title: bbgmsk.m % Author: Matt Wilbur % Date: October 19, 1998. % % Description: This function takes a NRZ sequences of bits % (one sample per bit) and returns the phase % of an MSK and GMSK signal modulated by them. % % It also returns the baseband in-phase % and quadrature components of the GMSK % signal ready for upconverting. % % This function accepts as arguments: % % bits - NRZ bit stream (one sample/bit) % Rb - baseband bit rate % ns - number of samples per bit % BT - normalized bandwidth of Gaussian filter % % Modified: % Set up some timing variables Tb = 1/Rb; fs = ns*Rb; Ts = 1/fs; % Extend the number of bits by one to make the convolution below % work out nicely numbits = max(size(bits)); bits(numbits+1) = bits(numbits); % Generate the msk phase first bup = upfirdn(bits,ones(ns,1),ns,1); bscale = bup * pi/2/ns; bscale(1) = 0; msk = cumsum(bscale); % Get the Gaussian impulse response % 3-dB BW of filter Bb = BT / Tb; % Time scale for filter --- 6 Bit periods to be safe t = -3*Tb:Ts:3*Tb; % Analog impulse from formulae h_a = sqrt(2*pi/log(2))*Bb*exp(-2*pi^2*Bb^2*t.^2/log(2)); % Digital impulse from impulse-response matching h_d = Ts*h_a; % Get the GMSK phase --- a few delay tricks so beware of shifting % indices [temp,delay] = max(h_d); y = conv(h_d, msk); upper_index = ns*numbits-1; gmsk_phase = rem(y(delay:upper_index + delay), 2*pi); msk_phase = msk(1:upper_index+1); t = 0:ns*numbits-1; t = t/fs; xi = cos(gmsk_phase); xq = sin(gmsk_phase); %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%>Hello, > >I am studying MSK modulation, does anyone know how to genrate a MSKsignal>in matlab, pls help me..Thanks. > >Gon. > > >
Reply by ●December 5, 20062006-12-05
"Jerry Avins" <jya@ieee.org> wrote in message news:AemdnVBMaPwpd-nYnZ2dnUVZ_oidnZ2d@rcn.net...> Heid the baw - goal!! wrote: > > ... > > > Not very helpful... > > Was it you in another guise who asked for help? If not, how do you know? > > Jerry > -- > Engineering is the art of making what you want from things you can get. > �����������������������������������������������������������������������Wasn't me,but saying' Try Googling...whatever' - we might as well all go home. You can imaging even the smallest gnat knows that one. Tam -- Posted via a free Usenet account from http://www.teranews.com
Reply by ●December 5, 20062006-12-05
Heid the baw - goal!! wrote:> "Jerry Avins" <jya@ieee.org> wrote in message > news:AemdnVBMaPwpd-nYnZ2dnUVZ_oidnZ2d@rcn.net... >> Heid the baw - goal!! wrote: >> >> ... >> >>> Not very helpful... >> Was it you in another guise who asked for help? If not, how do you know?> Wasn't me,but saying' Try Googling...whatever' - we might as well all go > home. You can imaging even the smallest gnat knows that one.http://users.erols.com/jyavins/google.gif Jerry -- Engineering is the art of making what you want from things you can get. �����������������������������������������������������������������������
Reply by ●December 6, 20062006-12-06
Heid the baw - goal!! wrote:> "Jerry Avins" <jya@ieee.org> wrote in message > news:AemdnVBMaPwpd-nYnZ2dnUVZ_oidnZ2d@rcn.net... >> Heid the baw - goal!! wrote: >> >> ... >> >>> Not very helpful... >> Was it you in another guise who asked for help? If not, how do you know? >> >> Jerry >> -- >> Engineering is the art of making what you want from things you can get. >> ����������������������������������������������������������������������� > > Wasn't me,but saying' Try Googling...whatever' - we might as well all go > home. You can imaging even the smallest gnat knows that one.If that's the case, why did he ask something so basic? He should have got the basics from a range of places Google will offer him, and be asking deeper questions. Steve
