... car alarm with GPRS Automobile anti-theft device communication module GPRS as an independent module, the requirements as belows: 1, text messages and voice ... buttons and the A, B linkage. 2, can identify the alarm state of working conditions and illegal intrusion, and of text ... state: 3, telephone monitoring function. 4, with back-up power supply, even after power failure alarm. 5, no one line has been ...