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Comment by akelly | Hacker News Reader

Can we focus on longer range and penetration instead of higher bandwidth nobody needs at frequencies that require line of sight? What about the 900MHz band?

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Personally my group is working on a new reliable wireless based on wireless polarization of the EM waves with collaboration with Hitachi at 900 Mhz. The initial results are very promising [1]. It's already proposed to the IEEE but perhaps at the time the timing is not right, and it's not been very well received [2].

Recently our group have improved on the wireless system and the bandwidth is much better with MPSK rather the original BPSK. From simulation the improved wireless system is a few order of magnitude better than LoRa in term of BER performance with significantly improved range especially in multi-path environment. We are now trying to improve further with additional channel coding and more efficient modulation for better efficiency in real world application with linear power amplifier (PA).

Really hope this new polarization based wireless technology can get into the upcoming Wi-Fi 7 and 6G networks, to significantly improve wireless communication reliability for consumer and industry.

[1] Successful prototyping of a rotating polarized wave receiver for high-quality wireless communication in manufacturing environments:

https://www.hitachi.com/New/cnews/month/2017/09/170911.html

[2] Introduction to RPW Experimental Study of RPW system:

https://mentor.ieee.org/802.11/dcn/18/11-18-0357-00-0000-exp...

Hi, I participated in IEEE 802.11 a few years, 10 years ago, there is a lot of politics and you have to approach the main actors (at the time Broadcom and qualcomm) and discuss with them in bilateral meetings for maybe a year, to understand what they would consider or not.

Normally if the are business cases, they should be interested and help you. Yet because it's mainly about politics you will find one or two strong groups opposed to your group for whatever weird reasons, but mainly because they do not know you: You are outsiders.

After yet one or two years of 802.11 discussions, you will succeed because they will accept you as insiders.

Just for the anecdote, the internal wars within 802.11 were quite nasty for 802.11n in 2007, and when the group met at Hawaii, suddenly all people agreed. One participant said that seing all those nude breasts was an important factor for the adoption of the 802.11n proposal!

802.11n could have been ratified ~2 years earlier, but was blocked by Texas Instruments with their ridiculous spread-spectrum but-not-really standard. It's a good thing they lost, pity it took 2 years. OFDM won, as demonstrated by the following standards n,ac,ax (and 4G/5G cellular standards).

The topic of development culture and processes in highly technical industries is fascinating to me. The Intel and Samsung drama is great.

HA seems to be the only place where it crops up - is there a decent subreddit or other forum with further discussion?

You should talk with the folks at https://eridan.io/product/ .

They're shipping[1] 16384 QAM and their scheme is a much more power and bandwidth efficient than a linear amplifier. (In addition to the coding efficiency, they don't need guard bands.)

[1] That page says "14 bits or more". I can't tell you how many bits "or more" they can do but it is non-zero.

The 5GHz band is the only usable band where I live because the 2.4GHz bnd has longer range and better penetration. There are at least 5 visible networks on each of the 3 non-overlapping 2.4GHz channels from any given point in my house, and if I'm in a corner of the house (my AP is centrally located) there are more.

Longer range and better penetration means even more congestion in built-up areas. 2.4GHz is as low as you’d want to go in any application other than rural mansions.

yeah the switch to 5ghz was huge when i lived in an apartment. i had an ap in each room and i barely received any congestion in that spectrum because the walls blocked it all. i imagine it’s great for schools and businesses in the same way.

I’ve lived in several plaster and lathe buildings and other houses that would've benefited from longer range WiFi

My house is solid brick walls throughout. My WiFi is awful in any room without an access point.

We in wall access points (eg Unifis) are great for room coverage, and there are Ethernet ports on them too, so they provide a convenient switch too.

However doing a whole house wouldn’t be cheap.

Unifis? Are they homeplugs? (Ethernet over Powerline)

Homeplugs are awesome. Used them in Singapore due to concret walls everywhere which made Wifi basically useless. Had them in every room for Wifi + Ethernet.

> Unifis? Are they homeplugs? (Ethernet over Powerline)

No, they are accesspoints

> Homeplugs are awesome

They CAN be awesome. Depends on the wireing. But if they work, they work well. I just had to replug mine every week or so but this weas a few years ago. I ethernet hardwire everything now as Im just in a small room.

Brick walls don't block wifi that much - there's probably steel or concrete (or both) in your walls and floors. That kills wifi pretty good. In a traditional brick house you can get wifi coverage on 2.4 GHz, and for the most part 5 GHz as well, into the last nook and cranny with a single, well-placed AP.

There's definitely no steel in my house, however there is lime plaster which is somewhat similar to concrete.

I can get 2.4GHz fine, but it's pretty slow for a 1Gb/s connection. 5GHz only within the room of the AP in general (or the room immediately above/below, because the floors are just wood).

Shouldn't we be able to trade off the higher speed for less conflict by having each client spend less time taking up air space? Like if we can achieve 5GBps, than presumably there could be dozens of networks operating at ~200MBps speeds all sharing the same frequencies.

Wi-Fi 6 and newer opted for OFDMA instead of TDMA but it achieves the same goal of splitting the bandwidth dynamically based on client workload. OFDMA isn't coordinated over multiple APs though.

Problem with low frequency is that it penetrates everything and has the longer range. In urban environments the spectrum will just become congested to the point of it being useless (this already happens with 2.4GHz in big cities)

Is this true even with beam forming? Or does beam forming not work well with lower frequencies?

If there are too many ssids present and they're configured to allow low data rates (which they often are) even just the beacons broadcasting the existence of the networks can consume a reasonable portion of available airtime.

Saying nobody needs it is like saying who needs more than 640k of ram. Use cases are already there in AR/VR, and additional will follow as the technology becomes available.

Yeah, modern video cable standards are approaching 100 gbps. There's plenty of potential use for way more networking bandwidth than consumers have current access to. There may not be current applications, but I think that's much more to do with lack of access than lack of utility.

Wi-Fi HaLow 802.11ah. 902–928 MHz in North-America, 863–868 MHz in Europe, 755–787 MHz in China.

Pretty low bandwidth though. Mainly focussed on IoT.

I'm following https://www.morsemicro.com/ who is implementing it from the ground up. Some amazing talent there.

Wifi is not a replacement for cellular networks. As more and more people have wifi access points it makes sense to focus on speed and congestion management.

What I would like to see is the ability for wifi devices to relay others without having access to the data. Similar to a mesh network that every device supports and some sort of decentralized management allowing better signal for all devices.

WiFi is extremely power-hungry and most devices with WiFi are battery-operated (phones, tablets) - an arbitrary random mesh would only lead to dead batteries in a matter of hours.

This is already in place for IOT networks like Thread, but it’s only practical at very low bandwidth and where the routing devices are connected to a power source.

I, for one, would not appreciate someone burning through my battery to stream Netflix…

I live in a four-plex apartment, but surrounded by other low-rise apartment buildings.

There are at least 27 WiFi networks in the 2.4 GHz bands that all dance to share bandwidth. 5 GHz is dramatically better for us, more channels and less contention.

For cellular networks, however, the only reliable service is Verizon, because they have lower-frequency bands that can provide more range out here.

Do you have use cases in mind?

Unfortunately, you’re not going to get long range without more interference. Which makes it hard to deploy with any sort of density.

I have two APs in my house and get zero reception in the bathroom that's next to one of the APs because of the tiled lath and plaster walls. Same with the kitchen in my grandparents house.

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