Method of controlling the parameters of the pulse-Doppler onboard radar station while ensuring the energy stealth of its operation on radiation

Author(s):  
A.V. Bogdanov ◽  
D.V. Zakomoldin ◽  
S.I. Akimov

In the article, based on the mathematical apparatus of the statistical theory of optimal control in the state space, the synthesis of a method for controlling the parameters of the pulse-Doppler onboard radar system (BRLS) of a fighter aircraft is presented, in the interests of ensuring the energy stealth of its operation on radiation with a given probability, when detecting an air target-the carrier of a radio intelligence station, the optimal minimum local quality functional. The efficiency of the synthesized method is also evaluated on the basis of modeling. As part of the synthesis, the quality functional was determined and control signals were obtained for the parameters of the radar operation, which make it possible to ensure the energy stealth of the fighter's radar operation with a given probability in the process of approaching the radar carriers and the radio intelligence station (RTR). The indicators of the control signal efficiency determine the probability of correct detection of the radar of the air target carrier of the RTR station and the probability of non-detection by the RTR station of the sounding radar signal in the process of their approach. Based on the simulation, the effectiveness of the control signals is evaluated, which shows that in the process of approaching the fighter and the RTR carrier station, the energy stealth of the radar operation is provided with a given probability by controlling the parameters of the radar operation.

Author(s):  
A.V. Bogdanov ◽  
D.V. Zakomoldin ◽  
I.V. Kochetov ◽  
S.I. Akimov

The article proposes methods of counteraction to the enemy's electronic reconnaissance means, both for a duel situation and for group actions of fighters, analyzes their advantages and disadvantages, identifies limitations on their use. The physical meaning of these methods is to ensure the secrecy of the operation of on-board radar systems for radiation, due to the variation in the energy potential of the station, in particular, the time of coherent energy accumulation in narrow-band Doppler filters when receiving signals reflected from air targets and the radiation power of the transmitter of the on-board radar system when forming sounding radar signal packs. In the article, along with the methods of ensuring the secrecy of the operation of onboard radar systems of fighters, which make it possible to carry out technical measures only after radar contact with an air target equipped with electronic reconnaissance means, which leads to a decrease in their effectiveness, methods for controlling the secrecy of the operation of onboard radar systems of fighters are additionally given, allowing to provide stealth with a given probability in the dynamics of the approach of a fighter with its emitting airborne radar system with an air target, equipped with electronic reconnaissance means. In addition, it should be noted the method of managing the energy secrecy of airborne radar systems during group actions of fighters, within the framework of the development of which the possibility of summing up the powers emitted by the transmitters of the onboard radar systems of fighters when they work together for radiation in the position of conducting electronic reconnaissance is taken into account. Implementation of the developed methods will allow: to increase the survivability of fighters, and to an increase in this indicator, both the ensured secrecy of the operation of onboard radar systems of fighters for radiation and the implementation of the multi-position principle of building radar systems, given in the method of stealth control of the onboard radar system of fighters during group actions of fighters. to expand the combat capabilities of fighters, due to the fact that the covert operation of the onboard radar systems of fighters for radiation excludes the possibility of reconnaissance of the parameters of the sounding signal and, as a result, the possibility of setting active interference is excluded.


Author(s):  
Alexander V. Bogdanov ◽  
Sergey A. Gorbunov ◽  
Alexander A. Kuchin ◽  
Ali A. Hadur

On the basis of the mathematical apparatus of the statistical theory of optimal control, the method and algorithm of guidance of an air-to-air guided missile with an active radar target-seeking head when aiming at a «helicopter» class air target with various modes of its flight, including when hovering have been developed. The synthesis has been carried out as a result of flight experimental studies of radar signals reflected from a real helicopter. Also, recommendations for ensuring continuous tracking of a helicopter in an active radar target-seeking head have been presented


1996 ◽  
Vol 118 (3) ◽  
pp. 482-488 ◽  
Author(s):  
Sergio Bittanti ◽  
Fabrizio Lorito ◽  
Silvia Strada

In this paper, Linear Quadratic (LQ) optimal control concepts are applied for the active control of vibrations in helicopters. The study is based on an identified dynamic model of the rotor. The vibration effect is captured by suitably augmenting the state vector of the rotor model. Then, Kalman filtering concepts can be used to obtain a real-time estimate of the vibration, which is then fed back to form a suitable compensation signal. This design rationale is derived here starting from a rigorous problem position in an optimal control context. Among other things, this calls for a suitable definition of the performance index, of nonstandard type. The application of these ideas to a test helicopter, by means of computer simulations, shows good performances both in terms of disturbance rejection effectiveness and control effort limitation. The performance of the obtained controller is compared with the one achievable by the so called Higher Harmonic Control (HHC) approach, well known within the helicopter community.


2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Seung Jae Kim ◽  
Oh. Deog Kwon ◽  
Kyung-Soo Kim

Abstract Background This study aimed to investigate the prevalence, awareness, treatment, and control rates of dyslipidemia and identify the predictors of optimal control (low-density lipoprotein cholesterol < 100 mg/dL) among patients with diabetes mellitus (DM). Methods A cross-sectional study was conducted using the representative Korea National Health and Nutrition Examination Survey (2014–2018). Overall, 4311 patients with DM, aged ≥19 years, and without cardiovascular diseases were selected, and the prevalence, awareness, treatment, and control rates of dyslipidemia were calculated. Univariate and multivariate logistic regression analyses were conducted to evaluate the factors influencing the optimal control of dyslipidemia. Results Dyslipidemia was prevalent in 83.3% of patients with DM, but the awareness and treatment rates were 36.5 and 26.9%, respectively. The control rate among all patients with dyslipidemia was 18.8%, whereas it was 61.1% among those being treated. Prevalence and awareness rates were also significantly higher in women than in men. Dyslipidemia was most prevalent in those aged 19–39 years, but the rates of awareness, treatment, and control among all patients with dyslipidemia in this age group were significantly lower than those in other age groups. The predictors of optimal control were age ≥ 40 years [range 40–49 years: adjusted odds ratio (aOR) 3.73, 95% confidence interval (CI) 1.43–9.72; 50–59 years: aOR 6.25, 95% CI 2.50–15.65; 60–69 years: aOR 6.96, 95% CI 2.77–17.44; 70–79 years: aOR 9.21, 95% CI 3.58–23.74; and ≥ 80 years: aOR 4.43, 95% CI 1.60–12.27]; urban living (aOR 1.44, 95% CI 1.15–1.80); higher body mass index (aOR 1.27, 95% CI 1.13–1.42); lower glycated hemoglobin levels (aOR 0.71, 95% CI 0.67–0.76); hypertension (aOR 1.53, 95% CI 1.22–1.92); poorer self-rated health status (aOR 0.72, 95% CI 0.62–0.84); and receiving regular health check-ups (aOR 1.58, 95% CI 1.25–2.00). Conclusions Most patients with DM were diagnosed with dyslipidemia, but many were unaware of or untreated for their condition. Therefore, their control rate was suboptimal. Thus, by understanding factors influencing optimal control of dyslipidemia, physicians should make more effort to encourage patients to undergo treatment and thus, adequately control their dyslipidemia.


2020 ◽  
Vol 23 (6) ◽  
pp. 1783-1796
Author(s):  
Neelam Singha

Abstract In this article, we aim to analyze a mathematical model of tumor growth as a problem of fractional optimal control. The considered fractional-order model describes the interaction of effector-immune cells and tumor cells, including combined chemo-immunotherapy. We deduce the necessary optimality conditions together with implementing the Adomian decomposition method on the suggested fractional-order optimal control problem. The key motive is to perform numerical simulations that shall facilitate us in understanding the behavior of state and control variables. Further, the graphical interpretation of solutions effectively validates the applicability of the present analysis to investigate the growth of cancer cells in the presence of medical treatment.


2005 ◽  
Vol 20 (16) ◽  
pp. 3811-3814
Author(s):  
◽  
PAUL LUJAN

A new silicon detector was designed by the CDF collaboration for Run IIb of the Tevatron at Fermilab. The main building block of the new detector is a "supermodule" or "stave", an innovative, compact and lightweight structure of several readout hybrids and sensors with a bus cable running directly underneath the sensors to carry power, data, and control signals to and from the hybrids. The hybrids use a new, radiation-hard readout chip, the SVX4 chip. A number of SVX4 chips, readout hybrids, sensors, and supermodules were produced and tested in preproduction. The performance (including radiation-hardness) and yield of these components met or exceeded all design goals. The detector design goals, solutions, and performance results are presented.


2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Mohamed Elhia ◽  
Mostafa Rachik ◽  
Elhabib Benlahmar

We will investigate the optimal control strategy of an SIR epidemic model with time delay in state and control variables. We use a vaccination program to minimize the number of susceptible and infected individuals and to maximize the number of recovered individuals. Existence for the optimal control is established; Pontryagin’s maximum principle is used to characterize this optimal control, and the optimality system is solved by a discretization method based on the forward and backward difference approximations. The numerical simulation is carried out using data regarding the course of influenza A (H1N1) in Morocco. The obtained results confirm the performance of the optimization strategy.


1997 ◽  
Vol 119 (2) ◽  
pp. 217-222 ◽  
Author(s):  
Kunsoo Huh ◽  
Jeffrey L. Stein

Because the behavior of the condition number can have highly steep and multi-modal structure, optimal control and monitoring problems based on the condition number cannot be easily solved. In this paper, a minimization problem is formulated for κ2(P), the condition number of an eigensystem (P) of a matrix in terms of the L2 norm. A new non-normality measure is shown to exist that guarantees small values for the condition number. In addition, this measure can be minimized by proper selection of controller and observer gains. Application to the design of well-conditioned controller and observer-based monitors is illustrated.


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