I agree that the concept may be flawed, but the repeaters (aka WIFI extenders) do work.
I helped my relative install an extender just about 10 days ago. The one we happen to get is NetGear WN3000RP-100NAS. Don't take that as a recommendation, I don't like the set up at all, but it does work. Oh, the manual is awfully hard to understand...
This is how that one works in a nut-shell
First:
- In our case (our selected choice of repeater), the set-up process is very unforgiving. If you make a mistake or took too long and something timed out, best bet is to factory-reset, so have a paper clip ready. None of the screens I used were "correctable" when a mistake was made.
What it does is:
- It can be setup as an access point or extender.
- If you are extending, you should do the set up close to the main WiFi (say main WiFi SSID is main_WiFi). You want to avoid loosing the connection during set up. But just in case, get that paper clip handy. Factory-reset is much easier than to try to correct the mistake.
- You are given a "URL" in the manual. Boot it up, and you can WiFi connect to the extender's default SSID (or hardwire) and set it up using the Netgear provided URL.
- First page: You are asked to select Access Point or Extender.
- As repeater/extender, during the very unforgiving setup, it scans available networks.
- You select SSID main_WiFi as the one to be extended.
- You will need to properly connected to main_WiFi with appropriate password/security first. Once that is successful... You are given a few more screens of questions (like extender's SSID, password, etc. Say you choose extender SSID as Ext_WiFi), complete those screen. (My suggestion is to change only SSID but use default password so as to finish the unforgiving set up screens quickly. After initial set up, you can go back in to change the password)
- Once set up is completed ... Now you can move the extender (in theory) to elsewhere as long as that new spot still have some signal. The netgear extender has an LED showing if the extender has main_WiFi signal (or not). In my case, I pre-tested areas with my "Smart" Phone's WiFi. The best reception happens to be at a location that is very hard to get to, but has reasonable signal to main_WiFi, and I found no reason not to leave it right there since repeater's signal covered the rest of the apartment nicely.
- You can now connect to Ext_WiFi, and the extender in-turn pass it along to main_WiFi, bi-directionally.
Result:
It does work -- now my relative can move anywhere in her space and got great coverage.
Issues:
- IP address issue (which I have not explored in detail since it is not here but at my relative's home). The extender is default IP 192.168.1.250. The main_WiFi's subset happens to be the same. So once connected, you can't get to your extender using IP address, but you can get to the extender's set up via the NetGear provided URL.