Equalization and Symbol Rate

[gitaa]

Sir ,

I'm using Xilinx FPGA board with analog devices FMC card(adfmcomms1 ebz) to generate qpsk signal .this signal i'm giving to my ni5660 as input and using ni5660 PSK demodulator to see the constellation plot to measure imbalance in I/Qsignal.

I used carrier wave as 2.4 GHz and baseband sine wave signal of 1MHZ then i'm getting proper constellation plot as shown in fig 1.

but when i change the baseband signal to 2MHZ i'm not able to get correct constellation plot as shown in Fig 2.

gitanjali

[USBarnes]

gitanjali,

I just wanted to check, per my last comment, did you post to a new thread? Feel free to include the link here.

Could you also post images of the demodulation settings that you are using? Posting the code would suffice as well.

For something to try, make sure you update the demodulator settings to match the signal that you're trying to acquire. Getting the images or code from above will help us understand what we're dealing with a little better.