UDP/TCP stream data block formats

GNU Radio
1

Hello,

I want to stream data from an external sampler to Gnuradio over UDP or
TCP.

I am wondering about the data formats. As far as I was able to see with
Wireshark, for example float is 4 bytes IEEE format, but how is I and Q
arranged? Integer is 32bit wide, but again, how is it with I and Q.

Any hint to a document would be great!

Thanks a lot

Gnter (dl4mea)

2

On Fri, Jun 29, 2012 at 12:33:47PM +0100, Guenter K. wrote:

I am wondering about the data formats. As far as I was able to see with
Wireshark, for example float is 4 bytes IEEE format, but how is I and Q
arranged? Integer is 32bit wide, but again, how is it with I and Q.

Any hint to a document would be great!

gr_udp_{source/sink}.cc is probably a good place to start looking.

Note that the UDP blocks are agnostic of the data type (like most GNU
Radio stream handling blocks) and read the data as strings.
So if you transmit a gr_complex, think of it as a string of 8 bytes
length.
If endianness is something you’re worried about, that might actually be
a problem if your hosts have different endianness.

MB

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