I tried to seach but couldn’t find any discussion about it.
I was wondering if anyone has any good experience with ensuring good Wi-Fi coverage also inside elevators. Typical scenario would be Hotels or general Enterprise complexes.
The question is basically; How can we ensure customers have continouos WiFi in their elevator.
Let me summarize my ideas on how to do it;
We hope that installing an AP in the hallway outside the elevators, on each floor, gives enough coverage into the elevator shaft and elevator that you can roam and stay online.
This may or may not work, depending on materials and such. So, a bit risky, needs to be tested.
We pull cables and install AP’s inside the shaft.
This is probably the safes bet? But the signals will bounce and i have no idea how it would propagate inside the elevator shaft. Thus, i wouldnt how many AP’s would be needed. 1 evert second floor perhaps?
We set up a PTP-link using either ePMP products or maybe V1000, from top of shaft to roof of elevator. And then fix an AP to the elevator.
This way you always have excellent WiFi in the elevator. But your put your faith in the PTP link. This may or may not work, depending on number of floors. If you put the ePMPs on indoor channels you avoid their sensitive radar detection, but… i dont know. Maybe a V1k is better as it beamforms, but i dont know what happens when the elevator is at the top and the link is at it’s shortest.
I do not know about you, but in Poland, the Office of Technical Inspection responsible for the operation of lifts does not allow the installation of any devices not related to the operation of the lift in the shaft in which the lift is moving. Check the rules first?
An option is to install a connectorized ap and radiating cables along the shaft.
Thanks for your feedback. I have actually not thought about if and what will be allowed, so thanks for bringing that up. That would be a job for our customer to check though, so i’ll point out to them that we need to understand the rules first.
I’m a product manager on the distributor side, but we like to be able to provide our customers with value added services such as network design and general advice.
Right now we have a customer who is working on an offer for a larger building, it’s in the design phase and we’re offering up a best-effort Wi-Fi coverage design for budget purposes.
We thought we were done, but it was pointed out that the project has required full coverage for elevators which was not really something we had been asked to look at from the beginning.
At this point in time I am just trying to see if there’s anyone here who has experience with this specific part of wireless coverage and if they have any good ideas on how to best solve coverage for lifts. It’s a use case I dont have any experience with from before.
You’re right though, leaky coax may be the way to go. I’ll have to investiage
Thanks. Yeah, if that is possible if would be the best thing. I have no idea about what goes and not in terms of elevators to be honest. So was hoping to get more input about what’s actually practical / possible from people with experience
So we’re up to the following potential solutions;
AP’s in lobby, close to elevator doors, for each floor.
Pro: Easy
Con: No guarantee for stable coverage and/or seamless roaming.
PTP from top to elevator roof + AP in elevator
Pro: Would provide excellent WiFi in elevator.
Con: Building code might make this impossible + not necessarily very easy to ensure stable PTP link for entire shaft
AP with directive antenna in top and/or bottom of shaft?
PRO: Removes PTP-link issue. Cheaper and “easier” than 2.
Con: potential issue with building code + might be difficult to ensure good enough coverage for the entire shaft
AP’s distributed in shaft
PRO: Could ensure very good coverage
CON: Building code restrictions + might not be easy to acutally do
Run of fibre or fitting CAT-cable along with elevator umbilicals, AP in elevator
PRO: Stable network, perfect WiFi. Sound like the best solution.
CON: BUilding code? Feasibility? Cost?
AP w/leaky coax
Not sure about this. Feasibility, cost, building code. Would it work better than AP + directive antenna?
I expect that relying on wifi outside the elevator will not work well and the best case option (if allowed by local regulations) would be to have an AP installed in the elevator carriage itself. This is not simple or easy or likely cheap of course. Another idea if any sort of powerline connectivity in the elevator carriage is possible to provide local wireless connectivity that way. Very tricky.
Mount an AP in the elevator and use a PTP with APTC enabled between the elevator and the ceailing of the elevator pit to make the transport. With the plus that you can also transport data for an IP Camera for the elevator.
the TP Link diagram seem to leave out serving wifi in the elevator. They don’t take into account serving mobile client as they ride.
Thinking about what happens when the doors open and close. You would probably have to set the channels in the elevator to be far away from the channel on the floor closest to the door. So the roam would be forced as soon as the door shuts. Then it wouldn’t “roam out” at each floor when the door opens.
When you finally step out of the elevator and move away down the hall… you should hopefully roam clean to a new AP on a different channel.
you must be careful if you have AP in an elevator unless it is on a unique channel. You would not want issues with wifi clients in the building connecting to that AP in the elevator. What might be the best is to put an AP with directional antenna and beam it down the shaft.
so have an AP with directional antenna pointing down the shaft to one on the elevator carriage with a directional antenna and operate in mesh mode between each other. Then add a third AP in the carriage and set to minimum TX power for users in the elevator to connect to.
thanks for replying, yeah, this is one of the scenarios / solutions I have thought about. But it has potential issues, like ensuring stability of the PTP link, seing as you have a moving client side, standing waves in the elevator shaft. And, as pointed out by Pshemo, perhaps building codes does not allow it at all.
But yeah, i do remember a customer we had using some 2.4GHz products for a warehouse elevator doing exactly this. It’s years ago though, and I dont remember the applicaiton or know if it worked 100%.
Yeah, i have seen things like this before. There are many suppliers that have products meant for elevators, but it’s still difficult to know how well they work.
I mean, these products are not magic. They are employing exactly the same techniques as any other WiFi-product. There’s no improved OFDM or any other features to ensure the link works perfectly at any hight, all the time.
But the product is perhaps designed to fit better, maybe. I dont know.
Still, it’s good to know large companies like TP-Link agrees that PTP can be the way to go
(Still, difficult to guarantee faultless WiFi operation this way I would imagine. Or maybe I’m too pessimistic?)
Agreed. That’s the goal So the PTP link needs to backhaul all the potential clients in the elevator.
Then again, there’s probably not going to be 10 people streaming netflix at 4K either…
I guess the most important thing would be to try and provide a seamless roaming experience for people using VoIP-like services and stuff like that.
James_Mifsud
(James Mifsud (Certified Instructor))
20
Hello,
I’ve done this before, please note elevator laws around the world are absolutely crazy.
So please check.
Anywho, most elevators especially newer ones already have been wired for data and usually have spare cables for upgrades like access control and cameras
Generally you can install a switch in the control panel or there may be a spare port.
Last lift I worked on had 6x fibre pairs spare; so we used a media converter and connected it to a spare power strip with fused power.
Speak to the lift contractor, they’ll work with you.
