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

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

#2
Apropos of absolutely nothing, but IIRC a "Star Trek" movie where a screenshot of one of the displays on some ship or another had the Shields Frequency up which allowed the enemy to match it and disable it, and back in the 80s(?) when this came out I remember thinking "237GHz" (or something like that) was an insanely high frequency and doubted it could ever be reached with any degree of stability. Physics: HMB

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

#5

Apropos of absolutely nothing, but IIRC a "Star Trek" movie where a screenshot of one of the displays on some ship or another had the Shields Frequency up which allowed the enemy to match it and disable it, and back in the 80s(?) when this came out I remember thinking "237GHz" (or something like that) was an insanely high frequency and doubted it could ever be reached with any degree of stability. Physics: HMB

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

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

#7
Something not totally clear from the title, but it seems the claimed rate was actually achieve with a transmitter structure similar to what you would find in coherent optics (see figure 4). Instead of coupling to fiber, they couple to a high speed photodiode that radiates at the ~140GHz laser wavelength.

EDIT: Noticed that after a closer reading of the paper, the real goal was to assess the LO phase noise improvement when moving from a RF synthesizer to a SBS laser and PD based LO.

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

#8

When incorporated into Wifi 18 in the year 2046, it will prove to realistically get around 500 MB/s, and have a hard time getting through most walls.

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.

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

#9

When incorporated into Wifi 18 in the year 2046, it will prove to realistically get around 500 MB/s, and have a hard time getting through most walls.

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
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