iMac Dropping a very strong WIFI Signal

I have 2 iPhones, 2 iPads, a MacBook Air and an iMac on my wifi system. The iMac drops signal on a regular basis, I can't use it for an hour without having to reconnect. The signal is very strong, and none of my other devices drop signal. I do not have to restart, although I've done that several times hoping that would rectify the situation, I simply click the wifi icon on the top bar of the display and it reconnects without delay.

Help me Rhonda, help help me Rhonda, help me get my wifi back! OK, it's not the Beach Boys, but the desperation is there.