Hello sudhir,

I could not understand the first problem ie about

scaling the y axis . I executed your code, but the

plot did not show 0-3.6, however for grid command

1.Either use it before psd command or use 'grid on'

command after the psd command.I have checked it out

and getting grid and y axis is 0-50 dB.

with regards,

--- sudhir.devarakonda@sudh... wrote:

>

> Hi All,

> I am trying to plot the power spectral density of a

> jittered square waveform using psd() command.The

> program is given below.This seems to work fine but I

> have problems in

>

> [1] scaling the y-axis (the plot shows 0 - 3.6 but

> psd spectrum shows around 50 dB) and for some reason

> the grid command has no effect in this program

> [2] is there any method to calculate the SNR in dB.

> [3] other than unifrnd(X1,X2) are there anyother

> distrubution commands

> that could be used.

>

> fs20*1e6;% Sampling frequency

> N24*32;

> t=0:1/fs:(N-1)*1/fs;% Time vector

> m=0;

> for i=1:1:1024% Loop for random phase

> d(i)=unifrnd(-1.0,1.0);

> m=m+d(i);

> end

> mean=m/1024;% Mean value of duty cycle

> mean

> j=1;s=[];

> for i = 1:1024 % Square wave generation

> s=[s

> 1.8+1.8*square(2*pi*1e7*t(j:j+31)+d(i),50)];

> j=j+32;

> end

> psd(s,length(t),fs,hanning(length(t)));% power

> spectral density

> axis([0,100*1e6,0,50]);

> grid;

>

> If some thing is not clear for then plz let me know.

> Best regards,

> Sudhir Devarakonda >

>

__________________________________

Hello sudhir,

I could not understand the first problem ie about

scaling the y axis . I executed your code, but the

plot did not show 0-3.6, however for grid command

1.Either use it before psd command or use 'grid on'

command after the psd command.I have checked it out

and getting grid and y axis is 0-50 dB.

with regards,

--- sudhir.devarakonda@sudh... wrote:

>

> Hi All,

> I am trying to plot the power spectral density of a

> jittered square waveform using psd() command.The

> program is given below.This seems to work fine but I

> have problems in

>

> [1] scaling the y-axis (the plot shows 0 - 3.6 but

> psd spectrum shows around 50 dB) and for some reason

> the grid command has no effect in this program

> [2] is there any method to calculate the SNR in dB.

> [3] other than unifrnd(X1,X2) are there anyother

> distrubution commands

> that could be used.

>

> fs20*1e6;% Sampling frequency

> N24*32;

> t=0:1/fs:(N-1)*1/fs;% Time vector

> m=0;

> for i=1:1:1024% Loop for random phase

> d(i)=unifrnd(-1.0,1.0);

> m=m+d(i);

> end

> mean=m/1024;% Mean value of duty cycle

> mean

> j=1;s=[];

> for i = 1:1024 % Square wave generation

> s=[s

> 1.8+1.8*square(2*pi*1e7*t(j:j+31)+d(i),50)];

> j=j+32;

> end

> psd(s,length(t),fs,hanning(length(t)));% power

> spectral density

> axis([0,100*1e6,0,50]);

> grid;

>

> If some thing is not clear for then plz let me know.

> Best regards,

> Sudhir Devarakonda >

>

__________________________________