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Investigation results of signal formation peculiarities are presented for the autodyne short-range radar system using the symmetric saw-tooth law of frequency modulation. Experimental data is obtained with the Gunn-diode 8mm-range oscillator with frequency tuning with the varicap help.
Analysis results of autodyne signals of the double-diode oscillator, which is under influence of the proper reflected emission from the moving object, are presented. The analysis is performed on the base of the autodyne mathematical model presented in the form of a system of two mutually-locked partial oscillators under condition of strong mutual coupling. Peculiarities of signal formation are considered...
Analysis results of coupling degree influence of the autodyne oscillator with an antenna are presented together with influence of the impedance characteristic type (soft or rigid) of the active element on the coefficients of autodyne amplification, autodyne frequency deviation and power transfer as well as on the noise parameters and characteristics. Analytical and numerical calculations of above-mentioned...
The autodyne characteristics are oifered to use for steady-state stability analysis of the UHF oscillators. Theoretical substantiation of the proposed method is performed on an example of the oscillating system's mathematical model presented in the form of two mutually-locked partial oscillators under a condition of strong coupling between them. Peculiarities of stable functioning zones for oscillating...
Main equations for calculation of autodyne response time constant, the boundary cutoff frequency of autodyne signal and sensitivity of a microwave oscillator are obtained. Investigations of dependence of these parameters on the oscillations mode choice and the form of an impedance characteristic of the active element are performed on the example of the Gunn diode autodyne of-8mm-range.
Data of the experimental studies of an energy potential and dynamic range of the normal and frequency stabilized by the external high-Q resonator autodynes based on planar 8-mm Gunn diodes are provided.
A mathematical model has been developed for a double-diode autodyne oscillator affected by the proper reradiation. The model represents two mutually-synchronized partial oscillators with time delayed coupling between them. It is possible for studying peculiarities of autodyne amplitude variations of the partial oscillators, autodyne variations of frequency and phase difference and, also, in the power...
Basic expressions for calculating noise parameters of the autodyne short-range radar sensor (ASRRS) have been obtained that take into account the self-noise of the UHF oscillator and the feed-source noise. The calculation results on the limiting sensitivity, energy potential and dynamic range width of an 8-mm Gunn-diode (GD) autodyne radar are presented.
Options and application opportunities of double-diode autodynes in microwave sensors are considered to radio-wave control dimensions of products, vibration and displacement parameters, velocity and movement direction of reflecting objects.
Calculations of phase, frequency and amplitude characteristics are performed as well as the output signal, which is registered in the power supply circuit of the autodyne oscillator with linear FM of radiation are carried out. Calculations are performed at different values of feedback parameter. At that, dependences of appropriate noise levels as functions of distance to reflector are given. The phenomenon...
Main expressions for calculation and analysis of features of phase, frequency and amplitude characteristics as well as output response, which is registered in the power supply circuit of the autodyne oscillator with frequency modulation are obtained. Final expressions for functions of delayed impact are derived with account of real conditions of autodyne system operation in short-range radar of mm-range.
Operation principle, adjustment approach and construction description are given for double-diode autodyne module of 8mm-range made on the base of two mutually-synchronized partial oscillators on Gunn diodes. The block-diagram of a workbench is presented for determination of the motion speed and direction, vibration parameters and displacements of reflecting objects with the help of double-diode autodynes.
The mathematical model of operation of frequency modulated autodyne radar is developed. The model is presented in the form of an oscillator situated under influence of the proper reflected radiation from a radar object and inherent oscillator noises. Options of frequency modulation in the supply circuit and by means of capacity variation of the varicap embedded into the oscillator are considered....
Calculations of main characteristics of a two-diode autodyne subject to the influence of eigen reflected radiation are performed. It is used, at that, a mathematical model in the form of two mutually synchronized partial oscillators with a delayed mutual coupling between them. Particularities of behavior of amplitude and phase characteristic variations of partial oscillators, frequency and phase difference,...
The offered calculation procedure for the permissible output of a breakage face by gas factor is based on the equation of methane emission in the breakage face area from coal and roof and floor rocks. The model includes permeability and absorption of coal, porosity and thickness of coal seam, breakage face length, methane pressure and the operational safety-permitted methane concentration in the return...
The paper presents the results of the development the phase detectors for 2-millimeter two-frequency interferometer. Proposed circuit solutions allow eliminating the ambiguity of phase measurements when using the AD8302 chip and measuring the fast phase changes within 0–3600, and relative phase measurements in the range N∗2π, (where N < 66). The phase detectors have been tested in the heterodyne...
Radar sensor for use in automatic shunting system which executes remote control of track occupancy on hump yards and railroad switches and cut speed control passing along retarder position is developed. The sensors are equipped by systems of remote control and internal parameters diagnostics transmitting the radar and service information to the control point. The sensors could be applicable for use...
The principals of range resolution improvement the self-mixing FMCW radar based on analysis of the spectrum of high-order harmonics of intermediate frequency is proposed. Developed the scheme and investigated the model of Ka-band surveillance self-mixing FMCW radar with digital control and spectral processing of receiving signal. Advantages of this radar are small size, low power consumption and use...
The design concept of F-band heterodyne vector network analyzer is considered in this paper. The description of the flow chart, the main parameters and the results of tests of breadboard model are given.
The results of development of low cost radar sensors for remote control of track occupancy and railway cars speed over the territory of hump yards under heavy weather conditions are presented. The radar sensor feature is application of Ka-band FMCW autodyne (self-mixing) transmitter and digital systems for forming sounding signal and spectral processing of received signals. Sensor is equipped with...
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