Can someone please explain this circuit?

Can someone please explain the attached circuit, Can output of this circuit be fed to the PIC?
It is of a microwave motion sensor and I found this circuit on the internet, I have ordered this sensor module and would like to get some groundwork done in understanding the working of this circuit.

My understanding is that this circuit amplifies the output from the sensor which is in few microvolts, but I would like to know what excatly does CW operation means, does it mean High/Low kind of output. Like High output when presence is there and Low when no movement is detected ?

I can't, but the application/data sheet might help someone else. CW is continuous wave, versus pulsing the unit on and off to get the readings:

CW is as scalerobotics correctly stated Continious Wave. That's just a fancy way of saying an UnModulated signal, or just a carrier. Ham Radio uses this to send Morse Code, it is simply an interrupted carrier. The schematic shows a pulse train going into the circuit, this is a power saving technique which your PIC can provide. What to DO with the signal at the pre amp terminals. . . I have no clue.

The circuit amplifies the signal coming from the sensor by about 127,000 times. The high-frequency cutoff is around 500Hz.

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Originally Posted by Charles Linquis

The circuit amplifies the signal coming from the sensor by about 127,000 times. The high-frequency cutoff is around 500Hz.

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So is it possible to count the pulses at the outpt using PIC then and take a decision based on that (i.e. the frequency)?

Since the 2nd opamp is functioning as an integrator, no pulses are output.

It is a filtered pure analog signal. So you need to acquire it by the A/D module of your controller.

What you are going to do next is a matter of programming.

You may have to look for rapid changes of the signal.

An Osciloscope would help here alot.

Ioannis