HB100 Doppler sensor

I have initiated this topic in this forum after getting suggestions from Mr TomGeorge regarding how to use this forum
I am a novice hence the following request please
Kindly let me know the wiring information of the following HB100 board. What to connect with IN1 and IN2 and also Vcc and GND near the preset side. This may be used for optical coupling, I think! Where is IF out put of the HB100? totally confused. kindly help.
I am a hobbyist
I have googled HB100 with respect to this unit but in vain
I have Arduino UNO R3 and successfully tested some projects with HB100 but the present unit is little different from the general HB100 as shown in the attached file

RKI 2680 HB100_datasheet (1).pdf (265 KB)

Since this is an intruder alarm, I would guess the in1 and in2 are connected to the internal relay which will close when an intruder is detected.

Vcc is 5 volts DC.

How is this Arduino related?

Paul