Hq16, need help with defending

For every defence I get attacked, I lose almost 4 times a day. Like yesterday, I got attacked four times and lost them all. They were all TMed. I need help with good defence designs and prototype weapons that don't require the complex gears as they are damn right rare. I try using the HQ shield thing, but it doesn't work. My weapon lab is level 1 btw. I am at level 46 and my armoury is maxed for hq16.