Welcome to Labor day, or as we refer to it this year: August 36th. While being retired means it's not even a long weekend, it's one of those rare years where Labor Day is Mrs. Graybeard's birthday. As we tend to do, I offered to take her to dinner if she'd pick the place and she picked here. I started smoking a pork butt at 4AM and it was ready to take out of the smoker and pull by 5:15 PM.
We were treated to a pretty Falcon 9 Starlink and ridesharing mission last night at 10:09 PM EDT with weather better than the last several launches. That meant we got to watch it until the second engine started and it powered in a direction behind some thicker (or maybe just stretched out longer) clouds. The flight was the 40th mission of the year for SpaceX in the 36th week.
Not merely a Starlink mission, Starlink 4-20 was SpaceX’s sixth Starlink rideshare. Sitting atop the stack of 51 Starlink V1.5 satellites was an experimental spacecraft built by Spaceflight Inc. Known as Sherpa-LTC2, Spaceflight and partner Astro Digital turned the orbital transfer vehicle (space tug) into a satellite for customer Boeing. The purpose: carry and test a prototype communications payload built by Astro Digital and designed to verify new V-band communications technologies for a planned constellation of Boeing satellites in Low Earth Orbit (LEO).
The US Federal Communications Commission (FCC) approved Boeing’s plans for a 147-satellite V-band constellation in November 2021. It’s unclear what the purpose of the constellation would be or if Boeing already has customers or partners lined up. The prototype spacecraft built by Spaceflight and Astro Digital – known as Varuna in recent FCC filings – will be crucial for determining the constellation’s future. Boeing wants to use a swath of spectrum known as the V-band that has a higher frequency than the Ku and Ka bands commonly used by most other communications satellites. A higher frequency could mean higher connection speeds and more available bandwidth, but V-band radio waves tend to struggle to pierce through rain and other adverse weather conditions.
Awkward statement time. I don't know off the top of my head where V-band is because the nomenclature is honestly pretty devoid of meaningful clues. S-band comes before C-band when going up in frequency. L-band comes before S-band. Basically, when I come across a new designation, I look it up. The article mentions Ku and Ka, which I've worked with before so I know that Ku is in the vicinity of 14 GHz (that table says 12 to 18 GHz) while Ka is near 40 GHz (26.5 to 40 GHz). The table says V band is 50 to 75 GHz. When I worked on some V-band stuff, we just called it 60 GHz (although nothing about the system actually worked on 60 GHz. Go figure.)
I will note that oxygen absorption peaks in V band but toward the middle, around 60 GHz. The absorption isn't as bad at 50 or 75 Gigs, but nowhere is the loss as low as it is at Ku or even Ka band. Which might be a sign they're using V band because they don't want to communicate down to the ground.
Still, that's just interesting and not related to Labor Day.
Unfortunately, Labor Day has been more associated with unions than just the vast majority of people who work day in and day out to build a better life with their families, bringing along their communities and country. Because of their enormous influence in the Democratic Party, unions have
gotten themselves exempted from laws the rest of society
must follow - not to mention behavior that would get most everyone else locked away. Over and over again we've seen it demonstrated that unions can get away with things that no more conservative organization could possibly get away with.
Yep, V-Band is 50~75GHz, and we used to say "60GHz" for generic V-Band stuff at Hughes. We did a lot of V-Band stuff for various customers, I thought the waveguide was pretty small until I started working at W-Band, which is 75~110GHz.ReplyDelete
Ah, International Workers of the World day... Funny how those people who work the worst jobs never get this day off.ReplyDelete
Sounds lik e a Ukrainian inspired system that would allow communication with high altitude (recon?) aircraft that would be difficult to jamb from a ground level location. Any ground station throwing enough energy to interfere with the down link would be a dandy target for something like a neo-HARM missile. Somebody is planning another "Black" program that might allow real-time imaging of "interesting" locations.ReplyDelete
"Because of their enormous influence in the Democratic Party, unions have gotten themselves exempted from laws the rest of society must follow - not to mention behavior that would get most everyone else locked away. Over and over again we've seen it demonstrated that unions can get away with things that no more conservative organization could possibly get away with."ReplyDelete
Union = mafia. I learned this here in the rust belt when I was young.
So Unions are almost Congresscritters?Delete