need help with project

[surveillance101]

hi need help with a special project to be use in surveillance.

we are in need to build a prodject which will protect our back in a hostile country in south America.

we need the likes of a "PIR" alarm that would guard a gate or laneway which can inform us via a transmit signal to us at a approx distance of 100 to 200 meters away from the gate or lane way.

how can we build this in a simple matter what do we need PIR, transmitter and receiver how do we set this up can anyone help us thanks
Herman

 

[Externet]

...how can we build this in a simple matter...
Herman

Shine a secure held laser pointer to a solidly mounted mirror at the gate/laneway and a photodiode sensor back at the base bounced point.

No power supply that can fail/tampered requiered at the gate, Falling leaves/animals could trigger the beam but take them as functional system self-test .

PIR does not have much range, and also suffers from false triggering from wind, leaves, animals.