无线防盗报警设备中同频干扰信号软件检测方法

Soft Checking Method for Co-Channel Interference Signals in Wireless Theft-alarm Equipments

描述了无线探测器同频干扰现象对无线报警器系统带来的危害,在简要介绍编码芯片信息帧格式、接收电路内部噪声与外部杂散电磁波干扰输出特性基础上,详细分析了各类同频干扰信号的来源及其特征;提出了一种简单、有效的同频干扰信号检测方法,给出了完整的检测流程与检测参数的选择依据,指出了系统受到恶意同频干扰后的动作。该方法可在基于MCU软件解码过程中同步进行,MCU资源占用率低、响应速度快且可靠性高,能准确识别周围无线探测器正常操作触发信号与恶意同频干扰信号,有效地提高了无线防盗报警系统的可靠性。

The harm brought by the co--channel interference signals in wireless theft--alarm system was described in this paper. Based on the introduction of framing format of encoding chip, inner noise of receiving circuits and external stray electromagnetic wave interference, source and characteristics of all kinds of co--channel interference signals were analyzed in detail. A simple and effective checking method for co--channel interference signals has been given, moreover, a whole checking flow and the basis for selecting parameter was also offered in this paper. The operation of system when it was under attack of co--channel interference signals was introduced. The method can operate synchronously in the soft--decode process based on the MCU. The MCU can identify the normal triggering signals sent by the wireless detec- tor from the co--channel interference signals. Due to the excellent characteristics such as low data demanding, high speed of response and re- liability, the method enhance the reliability of wireless theft--alarm system.