Project25_MASTR
Millennial Graying OBT Guy
When I was FTR, during the roll out of Smartnet 1 we were sweating 500 milliseconds access time. Then P25 rolled out and added over 160 milliseconds IMBE latency to turn voice into concentrated orange juice, load it on the truck, transport it across town , add water and then reconstitute the finished product.
2100 milliseconds is just way too much for any sort of tactical application. And wasteful of human resources during a dispatch environment.
Satellite telephony got phased out to transatlantic fiber, because the delay to/from a geostationary satellite was unnatural to users. That delay was in the order of 250 ms (I am probably a bit off, not bothering to calculate today, post Irma).
This 2100 milliseconds is crazy, Skype isn't even that bad. OK maybe in half duplex it isn't that noticeable, however it does significantly delay tactical response and might I remind you all, in a dispatch situation, those missing seconds add up to a huge backlog of calls for service. Think carefully about the erlang, not in the context of the transmission media, but in the unavailability of the channel during those seconds between exchanges in a message. Imagine dispatching a huge fleet during a busy hour and each and every 4 to 6 second transaction taking an extra 1.5 seconds.
It is dumb dumb dumb. Design engineers need to sit in a dispatch center for a week.
Sent from my SM-T350 using Tapatalk
It is due to software DSP. Hardware DSP isn't nearly as bad (I've actually talked to some of Motorola's cellular engineers who've worked on FirstNet and Wave gear) but it puts the price of the handset in the $5000 range currently to equip a cellular device with hardware DSP.