Throughout the world,most of the existing seismic alarm systems calculate magnitude and locate an earthquake through the seismic network;the accuracy of early warnings is improved by increased network density.The accuracy of basic parameters of the earthquake will be correspondingly improved.However,it takes a lot of manpower,material,and other social and public resources to use this method.Meanwhile,the seismic network itself has shortcomings in the complexity of multi-stations and the vulnerability of the network system.Due to economic backwardness and communication underdevelopment,most parts of our country still lack an earthquake early warning system;these areas are in the earthquake belt,so it is necessary to provide a seismic alarm in this area.This paper is based on the principles of earthquake early warning,computer technology,and sensor technology.It introducess the principle of earthquake early warning and discusses the possibility of rapid determination of earthquake parameters using only a single seismic monitoring sensor module.We also complete the hardware and software design of the earthquake warning sensor module for seismic monitoring and expound the process to determine earthquake parameters algorithm in detail.After an earthquake occurred,the P-wave of seismic propagated to the seismic monitoring station.First,the sensor module system was triggered using the short-term average/long-fterm average(STA/LTA)technique and the P-wave was picked up automatically.Second,on the basis of a traditional method,we used the initial motion direction of the three P-wave components to determine the epicenter azimuth at the seismic monitoring station.Finally,we used the first motion displacement of the three P-wave components to determine the epicenter azimuth.However,due to the high error of the azimuth based on this method,we have improved it to calculate several seismic azimuths by using information from the P-wave initial motion,and the arithmetic mean is used as the final value of the azimuth.As earthquake magnitude has some mathematic statistical relation to the predominant period of the Pwave,and the maximum displacement amplitude of different earthquake magnitudes has a certain attenuation relation to the increase of the hypocentral distance,we calculated the predominant period and maximum displacement amplitude with the collected acceleration data during the first three seconds after the P-wave’s arrival.Once the magnitude of the earthquake and the hypocentral distance are determined,a warning is sounded,achieving the goal of earthquake monitoring and early warning.The minimum acceleration the earthquake monitoring sensor module used here can distinguish is less than 1gal,and the range of acceleration is±2g.It also can collect acceleration of the three components simultaneously,and every sampling frequency could reach to 500 Hz.The power is 350mW under normal conditions;it is thus suitable for outdoor use.The maximum error range of the azimuth is±15°,and the average error is 11°;compared to the 8.5°average error of better seismic monitoring stations,the data here are a little larger,2.5°,because the earthquake magnitude and hypocentral distance are calculated by two statistical relationships,and it has a±0.412magnitude error and a±1.59kilometers hypocentral distance error.Compared to the traditional way that seismic networks determine earthquake parameters,the basic parameter calculated here has a larger error,but it has a lower demand for a single earthquake monitor to determine basic parameter of the earthquake.So it is practicable to determine the basic parameter of an earthquake by a single earthquake monitor sensor module.