Faster Linking for good SNR circuits

[guitarpicva]

In an attempt to move data more efficiently when good SNR circuits exists, a suggestion is to have a Fast Link Set Up (FLSU) waveform which could be used when appropriate. I believe that the current 14 byte payload waveform is used (is that correct??) but it is still nearly 4 seconds in duration.

This could be an additive feature, vs. changing Mercury fundamentally. If conditions are known to warrant it, try FLSU first, then fallback to Robust.

A few observations:

a. "Backbone Circuits" -- moving larger message sets to more distant geographies means higher frequency operations, which in turn means higher SNR values. Shorter (higher data rate) link setup is easier with a higher SNR. This work might also commonly be done with stations which have better antennas and higher power.

b. Good circuits between ground wave or single hop NVIS can take advantage of this as well when utilizing Link Quality Analysis which leans heavily on SNR as a variable, combined with time of day and frequency in use.

This notion is witnessed in the 3G ALE waveform set (STANAG 4538), where an FLSU linking transmission is < 1 second in duration (same for ACK/NACK). This decreases scanning dwell to trap connection requests. S4538 is routinely used with 20-30W man-pack radios with modest antennas.

c. Time is a commonly forgotten component of radio communications. The faster a link may be set up and utilized, the faster that frequency may be returned for use by others.

d. Short transmissions also avoid interference better than longer transmissions (fades, QRM, QRN) to facilitate linking, which in turn does the "gear shifting" to choose a data transfer waveform/data rate.

[rafael2k]

Hi @guitarpicva. We are planning for some suggestions. I'll get back here soon.