The Research On The Separation Arithmetic Of The Wireless Interference Signal Based On The Multi-frame Statistical Spectrum

In recent years, the rapid development of wireless communication, so that in the future of human demand for spectrum resources will be more and more, people use the tense situation will become increasingly prominent on the frequency resources.Radio communication (or broadcast) system’s always use on the speech, image, video and digital signal from the transmitter to transmit to the receiving end.Usually these signals after the modulation and correlation processing then using radio signals emitted into the air.The receiver will radio signal after demodulation and processing become to the original voice,video, image reduction and digital signal. The two signals:radio signal and the original voice, image, video and digital signal. Observed from the communication point of view, regardless of voice, image, video and digital signal, besides the signal characteristics of each other, in a communication system with the identity of the baseband signal.They have their own characteristics of the spectrum.Frequency spectrum characteristics of baseband signal baseband signal modulated radio signal generated after the are closely related, there are many situations is baseband spectrum in the frequency axis movement results. But the receiving end task, is to maximize the reduction characteristics are transmitted baseband signal, including spectrum characteristics.The radio interference if the transmission form of distinction, can be divided into production of conducted interference and radiation interference.Usually, according to the nature of interference source of distinction, is divided into natural disturbance and human disturbance. Natural disturbance from the natural phenomenon, is not to be controlled. There are static interference, the sun interference and the universe interference.Human disturbance sources from machine or other artificial devices, it is can be controlled. Human disturbance can be divided into radio interference and non radio equipment interference.the industry, scientific research, including the interference interference of medical electrical equipment, power line interference of Non radio equipment. In order to prevent the cause harmful interference to radio business, national standard has been to the frequency and radiation allowed value made provisions.Radio interference refers to the radio frequency band (9KHz-3000GHz), may cause damage to the useful signal of the undesired signal or electromagnetic interference.It may affect the reception of radio communication system, such as performance, misunderstanding or lost information.When the harm to interfere with the normal operation of radio navigation or other security services or Serious losses and block or repeatedly blocked the wireless electric power according to the provisions of the normal development of open, this interference is called the harmful interference. It has important significance and separation of radio interference signal, with the rapid development of China’s radio career, extensive application of new technologies, new business of radio, radio stations (stations) quantity sharp growth, radio interference phenomenon becomes more and more serious, especially for the interference of aviation communication, water communication security service, a direct threat to social stability, national security and people’s safety of life and property.In order to effectively isolate the interference signal, we use multi-frame statistical spectral separation as the interfered signal separation processing and analysis of interference signal, so as to find the source of interference. This algorithm can be embedded into the radio spectrum monitoring system, according to the monitoring data in real time system can analyze a band if there is interference, if there is interference, can do some processing through the late.The Multi-frame statistical spectral algorithm is using GMSK modulation, firstly the MATLAB simulation of the interference signal, then the original signal and the simulation is divided into multi-frame accumulation statistics respectively, then FFT transform, superimposed on the spectrum is obtained by subtracting the interference signal. When the count the number of frames are enough, the spectrum parameter tends to a constant.The improved algorithm, the traditional power spectrum of originalFFT transformof modern power density for the AR model spectral density, obtainedbetter results..Experimental results show that, the algorithm can fast separation of the original signal and interference signal frequency spectrum of original signal in known cases, good effect and universal, the complexity of the algorithm is less than that of the traditional method.When the LabWindows/CVI software for frequency conversion of the received signal in the frequency domain analysis, extraction of signal detection and signal, can see through the AR model processed signal is better than that of FFT, so as to better realize the separation of radio interference signal.