Problem with vrt code

Hi All,

I am transmitting using tx_samples and receiving with
rx_streaming_samples. I use basic daughterboards. The signal transmitted
is just a sequence of the value 10000+10000j. The carrier frequency is
set to 10MHz. The interpolation/decimation rate is 64. The transmitter
is repeating i.e. “-r” option is used.

The plot shows the absolute value
of the received data when the transmitter is using vrt code. The plot shows the received signal when
the transmitter is using trunk code (checked out a few weeks ago). The
receiver is using vrt code in both cases.

The interval between the points where the signal disappears is
suspiciously close to 371. I think I also observed this “signal loss”
when looking at the signal output using oscilloscope (although it’s an
old analog scope and therefore difficult to say).


It looks like the trailer (which is zero) is being written into the
file. The vrt::expanded_header::parse routine should be calculating the
correct length from the header. This call can be found in the

I dont think the parser is wrong, nor do i think the
rx_streaming_samples is getting the length wrong. You may want to check
wireshark and verify what you are seeing over the wire.


I made a quick fix which seems to work. I simply changed MAX_SAMPLES in from 371 to 350.


Quoting Josh B. [email protected]: