基于現有公共電話網絡，結合射頻無線通信及傳感器技術，設計開發一種用于校園安防的智能報警系統。系統在探測器端上加入編碼發射電路，每個探測器編碼由12位組成，編碼信號包括探測器的位置信息和探測器類別信息。報警終端采用無線接收方式接收編碼信號，用單片機軟件譯碼取代專用集成電路芯片硬件譯碼，12位編碼數據位中的位置信息編碼位數和探測器種類編碼位數可根據實際使用場合靈活定義，突破了采用集成芯片譯碼只有4～6位數據位的局限性。實驗結果表明：探測器無線發送距離為200 m，在8位位置信息碼，4位探測器種類信息碼，每位兩種狀態的編碼方式下，每個報警終端可接入探測器的數量達256個。

Abstract:

?A kind of intelligent alarm system for campus security is designed based on public telephone network. This system integrated the technologies of radio frequency wireless communications and sensors. Coded and emitter circuit was added in detectors， each detector’s coded was consisted of 12 bits， and detector-s coded signal included its position information and category information. Encoded signals were received by alarm terminal through wireless receiver， and software decoding method was used to replace the method of application specific integrated circuit decoding. The data bit of position information and category information could be defined according to applications flexibility， which breach limitation of only 4～6 data bits in the method of integrated circuit decoding. Experimental results show that detector-s wireless transmission distance can reached 200m， and the number of detectors which placed in one alarm terminal is up to 256， under the circumstances of 8 bits position code， 4 bits category code， and each bit included 2 states.

?

?

?