I did a full reset of the router - and then everything was fine. I have since updated the iPad iOS 7 - still fine. Worked at my mom's house as well - she has an AirPort Express as do I.
For what it is worth here is the info on the router - It is an AirPort Express, have no idea about it saying the card type is AirPort Extreme (something for others to address):
Menu Extra: 6.2.2 (622.2)
configd plug-in: 6.2.5 (625.6)
System Profiler: 6.0.1 (601.1)
Network Preference: 6.2.2 (622.2)
AirPort Utility: 5.6.1 (561.3)
IO80211 Family: 3.2 (320.1)
Card Type: AirPort Extreme (0x14E4, 0x87)
Firmware Version: Broadcom BCM43xx 1.0 (22.214.171.124.4)
Country Code: US
Supported PHY Modes: 802.11 a/b/g/n
Supported Channels: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 36, 40, 44, 48, 52, 56, 60, 64, 149, 153, 157, 161, 165
Current Network Information:
George Harcourt's Network:
PHY Mode: 802.11n
Country Code: US
Network Type: Infrastructure
Signal / Noise: -63 dBm / -92 dBm
Transmit Rate: 130
MCS Index: 15
Had the same problem with my iPad 2 at my parents' house (they have a third party router) BUT NOT AT MY PLACE (I use an Airport Express). I tried EVERYTHING with the iPad: reseting, hard-reseting, restoring via iTunes... I can tell you: NONE OF THIS WILL WORK. When my mom told her iPad 2 had the same issue since the last update to ios 7 (I think she skipped 10.6.3) I knew the iPads weren't the problem. It was the interaction between the software and the router.
ALL IT TOOK ME WAS A HARD RESET OF THE ROUTER. I didn't have to change any configuration in it or update the firmware. Not sure if it will work for everyone (they have a TP-LINK TL-WR941ND here) but if you can't make it work, I suggest changing the router. Do not believe if apple says you have to change your ipad! It has been working for the last 24 hs. I will update you if it doesn't work anymore.
Tried Hard resettting the Airport Extreme, resetting back to default values... Did not work on mine.
I am now more sure than ever it has to do with the IOS version as I am not able to see other networks in my neighbourhood whereas with my IPhone, and Mac, I can see at least 5 WiFi networks from the basement.
Like I promissed, I am giving an update: my connection is crap again. The signal started to get very weak, it started to drop the internet a few times and now it says the iPad is "unable to join this network" WHEN it finds my network that is. I looked up online and found these sugestions:
1- Change the router "Channel" to 6, instead of "automatic"
2- Change the "channel width" to 20 MHz instead of "variable 20/40 MHz". (Your max. Velocity will be 130 Mbps, be warned).
It has been working so far (couple of hours) and the signal is stronger than ever. But I am not going to jump into conclusions this time. I will give an update in one week to be sure this is the way to solve this problem.
By the way: iphone 4S and 5 working as a breeze.
It seems as Apple installes non-standard wi-fi modules into their devices. I have problem with wi-fi disabling every several minutes (3-5 min). My router set up to channels 7-11 because this range is most clear. With this setting all my devices (desktop, laptops, TV) work perfectly. But iDevices... May be that it is power saving...
The fact Apple does not follow to common standards we see in LTE support absent an many countries.