If you want is a square wave out then all you need is a single op amp and a potentiometer and voltage divider.
Put your input signal on the +input
Put +5 on one pot leg, the other to ground. From the wiper leg, 100K to 10k to ground. Junction of 100k/10K to op amp input. This will give you finer control of your 'trip point' for comparison. For examplem with the pot in the middle, wiper is 2.5V, but op amp will see ~0.225V. Dial the trim pot down until you get nice signal from the op amp with your 10mV input from the uwave device.