Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

240-Gbit/s sub-THz wireless communications using ultra-low phase noise receiver

jstage.jst.go.jp

Post reply on HN
Print view View original

21–30 of 67 posts

Re: 240-Gbit/s sub-THz wireless communications using ultra-low phase noise receiver

#21

Post by Yizahi »

matsz wrote: post #19
NavinF wrote: post #12

Earlier quoted context omitted.

Jokes aside, I get a consistent 1600mbps over wifi 6E which is good enough for me. Of course you need an AP in every room to get consistent performance, but wifi has always been like that. And unless your applications use forward error correction wifi will always have latency spikes from L2 retransmission if there's even one wall between the AP and device

If you live in a small/medium apartment then 6E is quite good. I've been using one of those "enterprise" tri-band APs for around a year and my experience has been also amazing, with just one AP in the entire flat. Enabling all bands should allow your device to just drop to 5GHz/2.4GHz when needed. This has been seamless for me.

Depends on the wall construction. Bricks or some AAC will be fine. Steel reinforced concrete panels - and you might as well call it Faraday cage.

Re: 240-Gbit/s sub-THz wireless communications using ultra-low phase noise receiver

#23

Post by Cthulhu_ »

connicpu wrote: post #9
I_Am_Nous wrote: post #8

Earlier quoted context omitted.

They are only transmitting 30 mm, when they moved to transmitting 20 meters it had to drop from 64QAM to 32QAM and lost some throughput. It's also laser generated so I don't believe it's omnidirectional, just point to point.

Sounds more practical for satellite-to-satellite communication than for consumer devices then if it's being sent with lasers

Might work well in open office and large public spaces though, there's quite a lot of things in between consumer and space.

Re: 240-Gbit/s sub-THz wireless communications using ultra-low phase noise receiver

#24

Post by Cthulhu_ »

kennethrc wrote: post #11
moreati wrote: post #5

Earlier quoted context omitted.

I thought it might be Generations, but that was 257.4 MHz https://www.youtube.com/watch?v=6A9IZHWz45Q&t=20s

That's the scene. Says it's from 1994. After that, I'm sure the Owner's Manual that comes with your new Enterprise-class Starship now has a "DO NOT DISPLAY YOUR SHIELD FREQUENCY" in the "Warnings" section

I mean I get that series like Star Trek rely on technobabble and suspension of disbelief, but surely an enemy can just... detect the frequency, or rapidly adjust their own like tuning in until it matches?

Re: 240-Gbit/s sub-THz wireless communications using ultra-low phase noise receiver

#25

Post by mmh0000 »

kennethrc wrote: post #11
moreati wrote: post #5

Earlier quoted context omitted.

I thought it might be Generations, but that was 257.4 MHz https://www.youtube.com/watch?v=6A9IZHWz45Q&t=20s

That's the scene. Says it's from 1994. After that, I'm sure the Owner's Manual that comes with your new Enterprise-class Starship now has a "DO NOT DISPLAY YOUR SHIELD FREQUENCY" in the "Warnings" section

To be fair, we don't know if Starfleet ever figured out how the Klingons bypassed the shield. Nor do we know if they ever discovered someone installed a rootkit on Geordie's visor.

Also, given Starfleet's continued examples of not learning their lessons from previous encounters, I suspect all ships still display the shield frequency in big, bold font. Possibly even visible from the viewscreen of the bridge on one of the rear consoles.

Re: 240-Gbit/s sub-THz wireless communications using ultra-low phase noise receiver

#26

Post by mmh0000 »

Cthulhu_ wrote: post #24
kennethrc wrote: post #11

Earlier quoted context omitted.

That's the scene. Says it's from 1994. After that, I'm sure the Owner's Manual that comes with your new Enterprise-class Starship now has a "DO NOT DISPLAY YOUR SHIELD FREQUENCY" in the "Warnings" section

I mean I get that series like Star Trek rely on technobabble and suspension of disbelief, but surely an enemy can just... detect the frequency, or rapidly adjust their own like tuning in until it matches?

That would work, but modern starships use a rotating phased tachyon field to prevent that.

Re: 240-Gbit/s sub-THz wireless communications using ultra-low phase noise receiver

#27

Post by ianburrell »

Palomides wrote: post #3

I'm curious about the use cases for 275 ghz wireless communication, are microwave links still common? it's almost far infrared

The same use as optical wireless like LiFi. Higher speed over short distances.

Optical has the advantage to bouncing off walls, but EHF may have bandwidth advantages.

This wouldn't be useful for microwave links since it is absorbed by the atmosphere and has short range.

275 GHz is one the edge of EHF. Terahertz is 300 GHz to 3 THz. Above that is infrared.

Re: 240-Gbit/s sub-THz wireless communications using ultra-low phase noise receiver

#29

Post by _fizz_buzz_ »

Palomides wrote: post #3

I'm curious about the use cases for 275 ghz wireless communication, are microwave links still common? it's almost far infrared

By far most communication is in the microwave bands, such as WiFi, cell phones, Bluetooth
Post reply on HN