Although my understanding of such things far from complete, I have heard that one of the biggest problems with high data rate radio is "smearing" of the symbols by multipath, and that if you can achieve little or no multipath (akin to analog TV "ghosting"), you can use much less robust modulation schemes to achieve higher symbol rates.
No doubt Guillaume can correct me on this. - Brian
On Sun, Mar 24, 2019 at 06:27:04PM -0700, Michael Fox - N6MEF wrote:
Guillaume:
A few questions is I may:
Answer 2 : In order to achieve links with omnidirectional antennas, you have to lower the datarate drastically. In order to do so, I would need to change lots and lots of things in my protocol, which is not designed for such low datarates. Therefore, I will not make such a development, sorry.
Why does the choice of antenna pattern affect the data rate?
Also, have you performed any testing to understand data rate vs. SINAD or SNR? If so, can you show what SINAD or SNR is needed to achieve each of the modulations (13, 14, 22, 23, 24)?
It appears that the modulation (13, 14, 22, 23, 24) is set statically in the master and applies to all remotes. Is this correct, or will the master dynamically change modulation for each client, depending on SNR?
Thanks much, Michael, N6MEF