usrp carrier frequencies mismatch

[g2009]

Figure A is what I transmitted. Figure B is what I received. As I know that it is because there is a Carrier Frequency Offset. How can I use LabVIEW programming to recover my signal, to eliminate this effect?

[vvkakade]

Can you attach the code being used. And the values of gain and connections used. Wired (SMA cables) or wireless ?

[g2009]

Files are attached. I am using wireless connection. This BPSK is supposed to get 100% correct message for most of the time.

[vvkakade · Accepted solution]

Few things to check which might help you determine or narrow down the problem:

1. What are the operating gains? Are they sufficient for the wireless domain ?

2. Can you reduce the base-band amplitude of the signal being transmitted to a values less than 1 ? Sometimes a high amplitude value of 1 can cause problems.

3. How does the waveform at the Rx end look like if you do not use the Frequency Offset Correction VI in the Rx VI?

4. Can you wire the two devices together with SMA cables and then check the waveform ? Any improvement ?

5. Read back the carrier frequency value once it is set on both the Tx and Rx side and verify that it is equal.

6. Do a simple smoke test to see that the two devices can indeed communicate with each other. Transmit a simple tone signal over a carrier and receive it on the Rx side. You may use the niusrp examples to do this smoke test.

Thanks.