Multifunctional intelligent wireless alarm system

Making use of rich inner resource of FPGA(Field Programmable Gate Arrays), a wireless alarm sending system is designed. It includes encoder, FSK(Frequency Shift Keying) modulation and every channel's control circuits, which can decrease volume and increase reliability of the alarm system. The demodulation of receive system is realized by an application specific integrated circuits MC3372. With the help of a single-chip microcomputer 89C51, the address decoder is also designed in the receiver. Adding to other anti-interference, the alarming system has effectively decreased the error-alarm rate. The system can install up to 128 channel sending devices. It can send an alarm to the host when there are some cases in stand-off areas, and the system will display on rotation multiple cases' area codes. The transmission distance is greater than 4Km in open zones. User can install more than one type sensors simultaneously, for example, smog sensor, combustible gas sensor or burglar sensor. Experiments show that the wireless alarm system has the strengths of high reliability, high anti-disturbance ability and low error-alarm rate. It can entirely meet the needs of alarm fireproofing and guard against theft, etc.