wifi is not connecting on my droid galaxy note ICS access point just showing saved

WIFI in my office through Linksys router WRH54G is not connecting on my Galaxy Note Android ICS. Mac filtering is there but no other security. I have registered the note's Mac address on router. When I am connecting it, it is only showing saved but not connecting and I have tried changing setting from DHCP to Static IP and input the following
IP 192.168.1.180
gateway 192.168.1.1
24 network suffix
8.8.8.8 or 172.31.6.5 (as shown in my laptop)DNS
4.4.4.4 or 172.31.6.85 DNS
Our DHCP setting is from 192.168.1.2 to 192.168.1.151 Please help me out. It is connecting at my home with Siemens wifi Router with WPA security.

Signal strength is excellent at my seat.

@setting from DHCP to Static IP and input the following IP 192.168.1.180.............
Our DHCP setting is from 192.168.1.2 to 192.168.1.151 @

I think you must put the DHCP setting from 192.168.1.2 (???) or 192.168.1.100>192.168.1.180 or 190 (because you put static IP on 192.168.1.180)