How to fix home Wi-Fi on iphone?

I have a galaxy s2 ant i can't connect to my home Wi-Fi it keeps saying obtain ip aderss, or poor connection network disabled. I need help.

Some smartphone Wi-Fi connections are stubborn when they come across certain networks when dhcp come into play.
Perhaps try creating a static connection by entering the ip/subnet & gateway settings manually.
IP address - specific number attributed to device. For eg. 192.168.1.150
Subnet - A method of indicating which part of an IP address is used to determine the network ID. Commonly, this number is 255.255.255.0
Gateway - Your router address, for eg: 192.1268.1.1

Select an IP from last few IP's of DHCP address range and give that IP on your galaxy S2 Wi-Fi adapter. You can also try changing the channel number on your Wi-Fi router.