MODE OF DETECTION AND ANALYSIS OF RADIO SIGNALS Russian patent published in 2007 - IPC G01S13/72 

FIELD: the invention refers to radio technique.

SUBSTANCE: the mode of detection and analysis of radio signals is in that they assign: the first threshold defined by the noise level of the receiving arrangement; the third threshold defined by the power of interference signals; the fourth threshold defined by the value of the effective square of reflection of the detected objects and also the value of the average of the proportion of the effective square of reflection σ_p from the ground surface. The radio signals are radiated, reflected radio signals are received and the average meaning of their amplitudes are found. This meaning is compared with the meaning of the first threshold and in case if the average meaning of the amplitude of the received signal is less then the threshold it is considered that reflected radio signals are absent and the process of their detection is repeated from the beginning, otherwise it is necessary to fulfill the following: the average meaning of the received signals are compared with the meaning of the amplitude of the third threshold and in case it prevails the third threshold it is considered that an interference signal is received and the process of detection of radio signals is repeated from the beginning, otherwise it is necessary to fulfill the following: the upper and the low borders of the spectrum of Doppler frequencies of radio signals reflected from the ground are calculated; the meaning of the second threshold starting out of the square of the spot of the directional diagram of the antenna on the ground is defined; radio signals are radiated once more during several cycles, reflected signals are received and accumulated forming a summary signal and the width of the spectrum of Doppler frequencies of the accumulated radio signal is measured, further analysis is executed in correspondence with the following logic: the radio signal reflected from the ground is received if simultaneously two conditions are fulfilled: the amplitude of the summary signal Us is bigger then the amplitude of the second threshold U_th2 and the width of the spectrum Δf_sp of the Doppler frequencies of the received radio signal is equal to the width of the spectrum Δf_sg =f_u-f_l of the Doppler frequencies of the radio signals reflected from the ground or if U_th4<U_∑<U_th2,_{but Δfsp≈Δsg; the radio signal reflected from the object being detected is received if U∑>Uth2, but, Δfsp<Δfsg or, if two conditions are fulfilled simultaneously: U∑≥Uth4 and Δfsp<Δfsg.}

EFFECT: allows detection and analysis of radio signals.

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