[peter5878]

You can use SDR to transmit any I/Q stream you want. I/Q is just a stream of two numbers for the strength of two phase-shifted carrier waves. How you encode your data (UDP packets) in the I/Q stream is up to you. SDRs like the LimeSDR Mini support sample rates of up to 30 MS/s, therefore it should be perfectly possible to achieve high throughput rates. On the receiver side you will also get an I/Q stream. The problem though is that it is not going to be the same of the transmitted I/Q stream. There might be a lot of noise, the carrier may be slightly shifted, the phase is not the same. Therefore you have to use some modulation to encode and decode the data. It is really up to you what kind of modulation to use. Some traditional ones are OOK (on-off keying), and some of the more complicated ones are APSK. LimeSDR Mini comes with example Python code to transmit raw I/Q. RTL-SDR should be enough for a passive receiver, but it is limited to 3.2 MS/s.