First of all, I do not have an electronics background. I have recently been experimenting with software radio using GNU Radio and a USRP1. I came here in hopes that some people outside of GNU Radio could lend some insight into my problem. I am not sure if I'll get any answers from here, but it's worth a shot.
We are experimenting with tunnelling a known communications protocol inside our GNU Radio transmissions. Within GNU Radio's modulators a packet_encoder class takes the incoming data stream, divides it into packets, and then sends it along to the modulator. The modulated data is then sent to the USRP for transmission.
Our problems seem to revolve around very short burst transmissions. For example, we are trying to perform a sort of hand-shaking process where one radio transmits a 'hello' packet and waits for a response. We are unable to reliably transmit single packets, but it seems we can get some throughput if we spam the same packet a few hundred times. Similar setups which continuously stream data from an input file seem to work fine in the same setup.
We have two USRP1 devices with suitable antennas located in the same room. As I have said continuous transmissions seem to work ok, but very short burst transmissions are a problem and we are not able to successfully transmit.
SO, my question is what are the various implications/issues surrounding short burst transmissions in radio? I am having a hard time finding the problem on the software side of things, and was curious if some insight into the hardware could help me. For example, are issues like this common in 'cheap' hardware like the USRP1?
Thanks for looking!