Features of Signals from Distributed Targets of an Autodyne Pulse Radar with Linear Frequency Modulation

Abstract

A mathematical model has been developed to describe the signals of an autodyne short-range radar system (SRRS) with simultaneous pulse modulation (PM) of amplitude and linear frequency modulation (LFM). The features of the formation of signals received from a distributed target in the form of an ensemble of an arbitrary number of point reflectors are considered. Calculations of signals by the proposed step method are performed for the case of two point reflectors on a location object situated at different distances from the SRRS. The distinctive properties of the signals generated when receiving the first and subsequent radiation reflected from the target are established. After sending the probing radiation, the reception of the first reflected radiation from a set of brilliant points is accompanied by the formation of a linear superposition of signals from individual reflectors. The reception of subsequent reflections causes the appearance of a combinational interaction of the signals of individual reflectors. The nature and magnitude of such interaction is determined by the magnitude of the feedback parameter of the autodyne SRRS, which depends on the values of the frequency deviation and the delay time of the reflected radiation. The results of experimental studies of the autodyne SRRS with simultaneous amplitude and LPM have been obtained using the oscillator module made on the 8-millimeter Gann diode.