I and Q Samples QPSK and 16 QAM Constellation Plotting

[VJKris]

Hi Experts,

I need some information on plotting the constellation diagram of a QPSK or 16 QAM or any other modulation.
I have the QPSK I and Q samples in an excel sheet.

Can i plot the constellation diagram with raw I and Q samples alone?

I know we can use MATLAB to check this out.But is there any other alternate to do it for example: with some formula and plot it in excel sheet?

Also is the constellation plot has the I as x-axis and Q as y-axis?I m new to it so please correct me...

Regards,
VJKris

 

[Shug]

This is straightforward. If you load the data into the variables "I" and "Q", just type "plot(complex(I,Q))" to get the constellation diagram. In Excel, just do some scatter plot with your x-axis as I and your y-axis as Q, as you said, and you should see it there as well.