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10 gigabit Ethernet 80 GHz point-to-point bridges

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41–50 of 94 posts

Re: 10 gigabit Ethernet 80 GHz point-to-point bridges

#41

Earlier quoted context omitted.

>higher sample rate ADCs and DACs becoming more viable Question, on optical networks doesn't this make dispersion more of a problem?

80 GHz isn't quite optical yet. It's a couple octaves down from infrared. SFAIK, it's still very much radio.

a great deal lower, the optical ITU DWDM grid is around 191.7 THz to 196.1 THz

Re: 10 gigabit Ethernet 80 GHz point-to-point bridges

#42

Earlier quoted context omitted.

80 GHz isn't quite optical yet. It's a couple octaves down from infrared. SFAIK, it's still very much radio.

a great deal lower, the optical ITU DWDM grid is around 191.7 THz to 196.1 THz

The more general dividing line between microwave and infrared ( outside comms ) is 300 GHz, which was what I meant.

Re: 10 gigabit Ethernet 80 GHz point-to-point bridges

#43

Crap, now I need to go buy a couple of these and lobby the nearest data center for some rooftop space. That is the short way of saying I had no idea you could get antenna this effective for wireless data transmission. I'd seen the 5mbps ones but nothing close to a gigabit much less 10 gigabits. Time to draw a 10km radius circle around my home address :-)

There are solutions that are lower end than this one, but still gigabit, at relatively affordable prices.

This Ubiquiti setup is $999 per side: https://www.ubnt.com/airfiber/airfiber5/

Re: 10 gigabit Ethernet 80 GHz point-to-point bridges

#44
post #43

Crap, now I need to go buy a couple of these and lobby the nearest data center for some rooftop space. That is the short way of saying I had no idea you could get antenna this effective for wireless data transmission. I'd seen the 5mbps ones but nothing close to a gigabit much less 10 gigabits. Time to draw a 10km radius circle around my home address :-)

There are solutions that are lower end than this one, but still gigabit, at relatively affordable prices. This Ubiquiti setup is $999 per side: https://www.ubnt.com/airfiber/airfiber5/

An AF5 or AF5X PTP link isn't a transparent 1Gb full duplex bridge, realistically you'll achieve 250-400 Mbps max. They're great radios but physics is still physics, 40 or 80 MHz wide dual polarity channel at 256QAM 5/6 code rate is not 1GbE.

Re: 10 gigabit Ethernet 80 GHz point-to-point bridges

#45

Earlier quoted context omitted.

a great deal lower, the optical ITU DWDM grid is around 191.7 THz to 196.1 THz

The more general dividing line between microwave and infrared ( outside comms ) is 300 GHz, which was what I meant.

That is true. One of the fun things illustrating first-hand how microwave/millimeter wave and fiber are the same thing is if you ever get to handle a 120 GHz band waveguide/feed. Some radar and military stuff operates in the 120 band.

It's so incredibly tiny and narrow compared to a 11 or 18 GHz microwave waveguide. Then imagine continuing to make it narrower while increasing the frequency, follow that to its logical conclusion and you have imagined a 9/125 fiber.

Re: 10 gigabit Ethernet 80 GHz point-to-point bridges

#46

Crap, now I need to go buy a couple of these and lobby the nearest data center for some rooftop space. That is the short way of saying I had no idea you could get antenna this effective for wireless data transmission. I'd seen the 5mbps ones but nothing close to a gigabit much less 10 gigabits. Time to draw a 10km radius circle around my home address :-)

The NSA Bluffdale facility might just squeak in that line for me. Think they'd hook me up?

Re: 10 gigabit Ethernet 80 GHz point-to-point bridges

#47
post #43

Earlier quoted context omitted.

There are solutions that are lower end than this one, but still gigabit, at relatively affordable prices. This Ubiquiti setup is $999 per side: https://www.ubnt.com/airfiber/airfiber5/

An AF5 or AF5X PTP link isn't a transparent 1Gb full duplex bridge, realistically you'll achieve 250-400 Mbps max. They're great radios but physics is still physics, 40 or 80 MHz wide dual polarity channel at 256QAM 5/6 code rate is not 1GbE.

Given the context that the parent was saying "I'd seen the 5mbps ones but nothing close to a gigabit", and was talking about a non-commercial setup, it still seems relevant.

Also curious...they show 5470-5950 MHz...from my layperson standpoint, that seems to allow for more than 80MHz wide. What's the actual story? The UBNT forums seems to indicate 2 separate 50Mhz channels, one for TX...one for RX.

Re: 10 gigabit Ethernet 80 GHz point-to-point bridges

#48

Earlier quoted context omitted.

a great deal lower, the optical ITU DWDM grid is around 191.7 THz to 196.1 THz

The more general dividing line between microwave and infrared ( outside comms ) is 300 GHz, which was what I meant.

Back in 60's AT&T make lots and lots of circular waveguide, intending to bury it across the country. One of the circular modes is dispersionless; then fiber was invented; lot's of money lost on circular waveguide.

Interesting that mmWavguide is still rectangular. Wonder if one could do a mmWave fiber? Don't see why not.

Re: 10 gigabit Ethernet 80 GHz point-to-point bridges

#49
post #47

Earlier quoted context omitted.

An AF5 or AF5X PTP link isn't a transparent 1Gb full duplex bridge, realistically you'll achieve 250-400 Mbps max. They're great radios but physics is still physics, 40 or 80 MHz wide dual polarity channel at 256QAM 5/6 code rate is not 1GbE.

Given the context that the parent was saying "I'd seen the 5mbps ones but nothing close to a gigabit" , and was talking about a non-commercial setup, it still seems relevant. Also curious...they show 5470-5950 MHz...from my layperson standpoint, that seems to allow for more than 80MHz wide. What's the actual story? The UBNT forums seems to indicate 2 separate 50Mhz channels, one for TX...one for RX.

That span is the total allowable space in the FCC part 15 rules for 5 GHz gear, where the AF5/5X has been tested and certified. Other radios can be used from 5200 to 5850 MHz (DFS frequencies permitting).

But the size of the channels it can operate in are 5, 10, 15, 20, 30, 40, 60 or 80 MHz wide. Software configurable on the radio.

Re: 10 gigabit Ethernet 80 GHz point-to-point bridges

#50
post #48

Earlier quoted context omitted.

The more general dividing line between microwave and infrared ( outside comms ) is 300 GHz, which was what I meant.

Back in 60's AT&T make lots and lots of circular waveguide, intending to bury it across the country. One of the circular modes is dispersionless; then fiber was invented; lot's of money lost on circular waveguide. Interesting that mmWavguide is still rectangular. Wonder if one could do a mmWave fiber? Don't see why not.

millimeter wave waveguide on the rear of a parabolic antenna (30, 60cm dish) is actually circular (cylindrical), supporting dual polarity operation (opposite H and V). Individual radio heads like this russian radio or other 80 GHz radios are still single polarity. In certain scenarios you can mount two radio heads on a T-shaped waveguide on the rear of one dish antenna, one in H, one in V.
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