用delphi开发的短信息预警系统，主要目的是用于水雨情预警，系统所用的短信息模块是wavecom fastrack GSM modem M1306B。-Use delphi to develop an early warning system of short message, the main purpose of early warning for water of rainfall, the system used by the short message module is wavec

使用串口modem发起at呼叫指令，用gsm , cdma modem群呼-Initiated at the call using a serial modem commands, with gsm, cdma modem group call

调制解调器（即Modem），是计算机与电话线之间进行信号转换的装置，由调制器和解调器两部分组成，调制器是把计算机的数字信号（如文件等）调制成可在电话线上传输的声音信号的装置，在接收端，解调器再把声音信号转换成计算机能接收的数字信号。-Modem (Modem), is a computer and telephone line between a signal conversion device that consists of two parts, modulator and demodula