E.V. Bogatyrev1, D.S. Vishnyakov2, K.A. Ignatkov3, O.A. Kuvshinov4, V.Ya. Noskov5

1 Siberian Federal University (Krasnoyarsk, Russia)
1 JSC «NPP «Radiosvyaz» (Krasnoyarsk, Russia)
2-5 Ural Federal University (Yekaterinburg, Russia)
1 bogatyrev-sfu@mail.ru; ²daniil.vishniakov.ru@gmail.com; 3 k.a.ignatkov@urfu.ru; 4 o.a.kuvshinov@urfu.ru; 5 v.y.noskov@urfu.ru

Due to the simplicity of the design and low cost of the transceiver, autodyne short-range radar systems (ASRRS) have found wide application as security sensors, speed sensors and collision avoidance of vehicles, meters for the movement of wagons on sorting slides, devices for contactless monitoring of biological objects, and much more. The principle of operation of these devices is based on the autodyne effect, which consists in changes in the oscillation parameters of the auto-oscillator (autodyne) under the influence of reflected radiation. The registration of these changes in the form of autodyne signals and their subsequent processing make it possible to obtain information about the reflecting object and the parameters of its relative motion.

This relationship between the parameters, which classifies autodynes as self-parametric systems with delayed feedback, is the reason for a number of features of the formation of signal and noise characteristics, which are most pronounced in the field of millimeter and shorter waves of electromagnetic (EM) radiation. These features include the presence of anharmonic signal distortions and periodic non-stationarity of the RMS noise level at the output of the autodyne in conditions of strong feedback from the "autodyne oscillator – location object" system. In ASRRS, as well as in SRRS with homodyne transceiver design, linear, sinusoidal and rectangular laws of frequency modulation (FM) radiation are widely used, significantly expanding the functionality of the systems. A large number of works have been devoted to the analysis of the features of the formation of signal and noise characteristics of ASRRSs based on microwave oscillors with different FM laws. These features have also been actively discussed recently in publications devoted to the study of semiconductor laser turbines with FM. At the same time, in the works known to us, the interaction of the oscillator with reflected radiation is described for continuous operation of the ASRRS. The case when pulse amplitude modulation (PAM) of radiation is present along with FM is considered using the example of ASRRS with an asymmetric sawtooth law of FM. However, in order to create promising ASRRS and their competent practical application, it is of interest to consider the properties of signal and noise characteristics also for other laws of FM. Therefore, the purpose of this work is to analyze the features of the formation of these characteristics of ASRRS with simultaneous PAM and FM according to a symmetrical sawtooth law. This law of FM in homodyne SRRS is quite universal, it provides, with relatively simple signal processing, the possibility of separately measuring the range and speed of reflecting objects, as well as the direction of their movement.

As a result of the performed studies of radio pulse autodyne with FM, it was found that the effect on the oscillator of the first partial reflection of its own radiation from the location object causes changes in the parameters of self-oscillations (frequency and amplitude) in accordance with the sinusoidal law. At the same time, the noise level at the output of the autodyne retains a constant value, determined by the intrinsic noise of the stationary mode of the autonomous microwave oscillator. At this step, ASRRS with simultaneous pulse and frequency modulation maintain the linearity of converting their own radiation reflected from location objects into an autodyne signal. Therefore, in terms of their properties, radio pulse autodynes with FM at the first reception step are similar to homodyne systems in which the transmitter and receiver are decoupled from each other. This property is quite important for the practice of using radio pulse autodynes with FM, since in this case the widest dynamic range of ASRRS is also provided, which is in demand to increase the system's resistance to interference. Subsequent reflections of EM radiation from the location object in the case when the feedback parameter is commensurate with unity cause anharmonic distortion of the shape of the autodyne signal, as well as the appearance of periodic instability of the RMS noise level at the signal output of the AO with FM. The phenomenon of noise instability, which begins with the second exposure to reflected radiation, manifests itself in the growth and exacerbation of noise peaks with each step.

The obtained research results significantly expand the known concepts of signaling and noise processes in radio pulse turbines with FM. These results should be taken into account when developing signal processing algorithms and using radio pulse autodynes in newly created ASRRS with FM in the millimeter range.

Bogatyrev E.V., Vishnyakov D.S., Ignatkov K.A., Kuvshinov O.A., Noskov V.Ya. Signal and noise characteristics of autodyne radars in the millimeter range with simultaneous pulse and linear frequency modulation according to a symmetrical sawtooth law. Achievements of modern radioelectronics. 2026. V. 80. № 3. P. 94–109. DOI: https://doi.org/10.18127/j20700784-202603-11 [in Russian]

1. Armstrong B.M., Brown R., Rix F., Stewart J.A.C. Use of microstrip impedance-measurement technique in the design of a BARITT diplex doppler sensor. IEEE Transactions on Microwave Theory and Techniques. 1980. V. 28. № 12. P. 1437-1442. DOI: 10.1109/TMTT.1980.1130263
2. Efanov A., Lübke K., Diskus Ch., Springer A., Stelzer A., Thim H.W. Development of a 35 GHz radar sensor. Proceedings of the seminar «Basics and Technology of Electronic Devices». Pongau. Austria. 1997. P. 11-16.
3. Usanov D.A., Skripal A.V., Postelga A.E. A microwave autodyne meter of vibration parameters. Instruments and Experimental Techniques. 2004. V. 47. № 5. P. 689–693.
4. Alidoost S.A., Sadeghzade R., Fatemi R. Autodyne system with a single antenna. 11th International Radar Symposium (IRS-2010). Vilnius. Lithuania. 2010. V. 2. P. 406-409.
5. Varavin A.V., Vasiliev A.S., Ermak G.P., Popov I.V. Autodyne Gunn-diode transceiver with internal signal detection for short-range linear FM radar sensor. Telecommunication and Radio Engineering. 2010. V. 69. № 5. P. 451-458. DOI: 10.1615/TelecomRadEng.v69.i5.80.
6. Ermak G.P., Popov I.V., Vasilev A.S., Varavin A.V., Noskov V.Ya., Ignatkov K.A. Radar sensors for hump yard and rail crossing applications. Telecommunication and Radio Engineering. 2012. V. 71. № 6. P. 567-580. DOI: 10.1615/TelecomRadEng.v71.i6.80.
7. Usanov D.A., Postelga A.E. Reconstruction of complicated movement of part of the human body using radio wave autodyne signal. Biomedical Engineering. 2011. V. 45. № 1. P. 6–8. 
8. Noskov V.Ya., Ignatkov K.A., Chupahin A.P. Primenenie dvuhdiodnyh avtodinov v ustrojstvah radiovolnovogo kontrolya razmerov izdelij. Izmeritel'naya tekhnika. 2016. № 7. S. 24–28 (In Russian).
9. Chernyavskij A.Zh., Danilin S.A., Voroh D.A., Danilin A.I. Primenenie pervichnyh avtodinnyh SVCh-preobrazovatelej dlya diagnostirovaniya ustanovok i oborudovaniya energeticheskogo i transportnogo mashinostroeniya. Datchiki i sistemy. 2021. № 3. S. 23–36 (In Russian).
10. Noskov V.Ya., Varavin A.V., Vasil'ev A.C., Ermak G.P., Zakarlyuk N.M., Ignatkov K.A., Smol'skij S.M. Sovremennye gibridno-integral'nye avtodinnye generatory mikrovolnovogo i millimetrovogo diapazonov i ih primenenie. Ch. 9. Radiolokacionnoe primenenie avtodinov. Uspekhi sovremennoj radioelektroniki. 2016. № 3. S. 32–86 (In Russian).
11. Noskov V.Ya., Smol'skij S.M., Ignatkov K.A., Mishin D.Ya., Chupahin A.P. Sovremennye gibridno-integral'nye avtodinnye generatory mikrovolnovogo i millimetrovogo diapazonov i ih primenenie. Ch. 10. Osnovy analiza i raschyota parametrov avtodinov s uchyotom shumov. Uspekhi sovremennoj radioelektroniki. 2018. № 3. S. 18–52 (In Russian).
12. Votoropin S.D., Noskov V.Ya., Smol'skij S.M. Sovremennye gibridno-integral'nye avtodinnye generatory mikrovolnovogo i millimetrovogo diapazonov i ih primenenie. Ch. 5. Issledovaniya avtodinov s chastotnoj modulyaciej. Uspekhi sovremennoj radioelektroniki. 2009. № 3. S. 3–50 (In Russian).
13. Komarov I.V., Smol'skij S.M. Osnovy teorii radiolokacionnyh sistem s nepreryvnym izlucheniem chastotno-moduli-rovannyh kolebanij. M.: Goryachaya liniya. Telekom. 2010. 392 s. (In Russian).
14. Noskov V.Ya., Bogatyrev E.V., Galeev R.G., Ignatkov K.A., Shajdurov K.D. Sovremennye gibridno-integral'nye avtodinnye generatory mikrovolnovogo i millimetrovogo diapazonov i ih primenenie. Ch. 15. Signal'nye i shumovye harakteristiki avtodinov s chastotnoj modulyaciej. Uspekhi sovremennoj radioelektroniki. 2022. T. 76. № 9. S. 15–54 (In Russian).
15. Giuliani G, Norgia M, Donati S., Bosch T. Laser diode self-mixing technique for sensing applications (Review article). Journal of Optics A: Pure and Applied Optics. 2002. V. 4. № 6. P. 283-294.
16. Sobolev V.S., Kashcheeva G.A. Self-mixing frequency-modulated laser interferometry. Optoelectronics, Instrumentation and Data Processing. 2008. V. 44. № 6. P. 519-529. DOI: 10.3103/S8756699008060058.
17. Usanov D.A., Skripal A.V., Astakhov E.I. Determination of nanovibration amplitudes using frequency-modulated semiconductor laser autodyne. Quantum Electronics. 2014. V. 44. № 2. P. 184-188. DOI: 10.1070/QE2014v044n02ABEH015176.
18. Bogatyrev E.V., Vishnyakov D.S., Ignatkov K.A., Kuvshinov O.A., Noskov V.Ya. Signal'nye i shumovye harakteristiki radioimpul'snyh avtodinov s linejnoj chastotnoj modulyaciej millimetrovogo diapazona. Ural Radio Engineering Journal. 2025. T. 9. № 3. S. 362–388 (In Russian).
19. Noskov V.Ya., Smol'skij S.M. Sovremennye gibridno-integral'nye avtodinnye generatory mikrovolnovogo i millimetrovogo diapazonov i ih primenenie. Ch. 6. Issledovaniya radioimpul'snyh avtodinov. Uspekhi sovremennoj radioelektroniki. 2009. № 6. S. 3–51 (In Russian).
20. Usanov D.A., Skripal' Al.V., Skripal' An.V. Fizika poluprovodnikovyh radiochastotnyh i opticheskih avtodinov. Saratov: Izd-vo Saratovskogo un-ta. 2003. 312 s. (In Russian).
21. Damgov V.N., Landa P.S., Perminov S.M., Shatalova G.G. Stohasticheskie avtokolebaniya v generatore s dopolnitel'noj zapazdyvayushchej obratnoj svyaz'yu. Radiotekhnika i elektronika. 1986. T. 31. № 4. S. 730–733 (In Russian).
22. Kulik V.V., Lukin K.A., Rakitynsky V.A. Autodyne effect in weak-resonant BWO with chaotic dynamics. International Journal of Infrared and Millimeter Waves. 1998. V. 19. № 3. P. 427–440.
23. Noskov V.Ya., Ignatkov K.A. O prichinah haotizacii avtodinnyh signalov v SVCh generatorah. Materialy 9-j Mezhdunar. nauchn.-tekhnich. konf. «Fizika i tekhnicheskie prilozheniya volnovyh processov». Ekaterinburg: Izd-vo Ural'skogo un-ta. 2012. S. 130–132 (In Russian).
24. Noskov V.Ya., Ignatkov K.A. Dynamics of autodyne response formation in microwave generators. Radioelectronics and Communications Systems. 2013. V. 56. № 5. P. 227–242. DOI: 10.3103/S0735272713050026.
25. Votoropin S.D., Noskov V.Ya., Smol'skij S.M. Sovremennye gibridno-integral'nye avtodinnye generatory mikrovolnovogo i millimetrovogo diapazonov i ih primenenie. Ch. 1. Konstruktorsko-tekhnologicheskie dostizheniya. Uspekhi sovremennoj radioelektroniki. 2006. № 12. S. 3–30 (In Russian).
26. Kuvshinov O.A., Ignatkov K.A., Noskov V.Ya. Primenenie sistemy FAPCh sintezatora chastoty dlya registracii avtodinnogo otklika SVCh-generatorov. Sb. statej desyatoj Vseross. nauch. shkoly-seminara «Vzaimodejstvie sverhvysokochastotnogo, teragercevogo i opticheskogo izlucheniya s poluprovodnikovymi mikro- i nanostrukturami, metamaterialami i bioob"ektami». Pod red. prof. A.V. Skripalya. Saratov: Izd-vo «Saratovskij istochnik». 2025. S. 313–320 (In Russian).