It usually needs to know the receiving parameters such as level and signal-to-noise ratio, etc., when using the wireless communication device, while the communication equipment without a screen depends on the managing computer. The portable terminal is designed because of the inconvenience of the computer when the using model is fixed and just monitoring is needed. The terminal with MSP430 MCU as the core intercepts the sending parameter and receives data via a serial port. The communication protocol is analyzed by comparing the receiving data and network data. The portable monitoring terminal has functions of data display, power indicator and strong electromagnetic interference alarm. The method of parsing the serial communication protocol has the universality in the equipment development with the serial ports.