GSM-Enabled Laser Perimeter Alarm

I need a compact laser-based perimeter protection system for a commercial site that immediately calls a predefined phone number whenever the beam is interrupted. The solution must combine reliable laser detection hardware with a GSM module (SIM800, SIM900 or similar) and the embedded code to place that outbound call within seconds of a breach. The finished unit should be self-contained, run from standard low-voltage DC, and include clear wiring diagrams and firmware source so I can duplicate or service it later. If you can integrate basic tamper detection, weather-proof housings, or an optional battery backup, mention that in your proposal—those extras would be a plus but are not mandatory. To accept the work I will power up the prototype on-site, break the beam and confirm that my test phone rings without false triggers over a 48-hour monitoring window.