Hi,

I would like to know whether I can feed BPSK modulated date to AD9122 DAC in FCOMMS1?

Then what will be the Q channel data?

Thanks,

Lismi

Hi,

I would like to know whether I can feed BPSK modulated date to AD9122 DAC in FCOMMS1?

Then what will be the Q channel data?

Thanks,

Lismi

Hi Chris,

You can find a lot of documentation on the internet, about

**P**hase**S**hift**K**eying, I don't want to pull out any of it specifically.If your modulator is 'connected', like Lars said in the answer above, you need to feed your demodulator just with the digitized I signal, and you should be fine. (Presuming that the modulator and demodulator using the same data mapping)

Thanks,

Istvan

Hi Csoml,

The BPSK modulator output have only I channel, right? Then how can I feed I and Q data inputs to DAC?

In the functional block diagram of AD9122 PCORE 2 DDS are shown. DDS-1a for generating I1, DDS-1b for I2, DDS -2a for Q1, DDS -2b for Q2. Then I1 + I2 giving I data and Q1 + Q2 giving Q data. In the case of DBPSK modulation what will be this I1,I2,Q1 and Q2?

Thanks,

Lismi

Hi,

Your signal will not be complete with just I or just Q, you need both, they are different components of the same signal. If your BPSK block only outputs -1 and 1 you need to do a mapping of these numbers to two vectors in the complex plane which are 180 degree to each other and use these vectors as your I and Q output. E.g. a simple mapping would be -1 = (I=-1, Q=0) and 1 = (I=1, Q=0). And this is what you feed to the DAC. Make sure you do apply proper scaling to the signal.

- Lars

Hi,

Your signal will not be complete with just I or just Q, you need both, they are different components of the same signal. If your BPSK block only outputs -1 and 1 you need to do a mapping of these numbers to two vectors in the complex plane which are 180 degree to each other and use these vectors as your I and Q output. E.g. a simple mapping would be -1 = (I=-1, Q=0) and 1 = (I=1, Q=0). And this is what you feed to the DAC. Make sure you do apply proper scaling to the signal.

- Lars