Strange problem with my Wi-Fi network

[applevinci]

Hi!
I have a very strange problem with my wifi network. I have TP-Link N750 (TL-WDR4300).
When I'm conneted to my wifi network iPhone and iPad is always connected to Wi-Fi. I woke iPhone or iPad and I see Wi-Fi signal bars immediately next to carrier name. On the another wifi newtwork, another place, another router everything is ok. I woke iPhone and first I see 3G/LTE, and later Wi-Fi signal bars.
On my wifi network is huge battery draining, iPhone is always working (see screenshot - on the top - other wifi network, below my wifi network). This is very strange problem. I'm fighting with it from 4 months :/

 

[Sirious]

There is no correlation between your network and a third party network.

 

[C DM]

Got to be something else in play running on the phone constantly other than just being on a different network which shouldn't affect that on its own.