Technical Research Of Wireless Signal Detecting Based On The Lyrtech

Before giant electro equipment, military equipment and systematic equipment assembling put into use, it is necessary to undergo the abnomal electromagetic leakage and compatibility testing. But restricted by the present condition, the testing of abnomal electromagnetic signal has to be proceeded on the site or the open environment rather than in the standard darkroom for some reasons. Furthermore, the traditional shielding chamber can not be widely used because of their high complexity and cost. The detection of abnormal signal in normal environment is based on statistical detection theory. By applying time-domain differential signal detection, this system could be used in signal acquisition. It is flexible, accurate, wieldy, user-friendly and with low cost. The system is able to be deployed at all time and space as will.To start with the wireless signal detecting, the background of the subject is explained in this thesis. Base on the study of parametric assumption checking method, the paper proposes a new method which is good for the detection of abnormal signal in normal environment. Using the lyrtech platform to set up the wireless baseband processing unit, designing a general RF front-end that realize the detecting of wireless signal, completed a PC control software and the interface based on the CPCI. Among them, the baseband processing unit includes VHS-ADC module, the matched data type module, the SDRAM memory module and the RTDEX data transmission module. The RF Front-end includes the control inerface module, AGC module, BSEL and filter group, two levels of mixing module, etc. The hardware system can realize the acquisition and storage of spatial signal, and data preprocessing, provide a accurate sample for the abnormal wireless signal detecting.Another major research content of this article is a statistical detection algorithm again st the abnormal wireless signal. First, it should pretreatment the wireless signal data w hich collected by the hardware system, such as time-frequency transform, the data fra me, Sample space building, and so on; this project studied the statistical detection alg orithm of wireless signal which is under the condition of complex background, it inclu des t-test, kolmogorov-smimov goodness-of-fit test, and rank sum test, it also realize various detection algorithm by using maltab. To verify the effectiveness of the algorit hm proposed in this article, it has set up a experimental platform to verification this sc heme. The experimental results showed that T-detection can be achieved detecting of the abnormal wireless signal in the high SNR environment, but also the KS-detection and the RS-detection can be achieved the abnormal wireless signal detecting in the low SNR environment.