Tracking Antenna Research Articles

Two-ray channel models with doppler effects for LEO satellite communications

In this paper we present some two-ray models with Doppler effects for Low Earth Orbit (LEO) satellite links. We show that satellite motion-caused Doppler shifts are different along the two rays, resulting in a time-varying phase shift. This is quantified with a few Doppler models and approximations. The combined interference effects, along with the path length difference caused phase shift, are calculated using a generic LEO pass-over. Channel gains are computed and compared using various antenna patterns and system parameters. The models show good agreements except for very low elevation angles. They demonstrate that a tracking antenna is effective in reducing fading for moderate to high elevation angles. Fixed patch antennas perform well. Omnidirectional and dipole antennas perform poorly. Higher carrier frequency and higher antenna height lead to faster fades. The fading becomes deeper at low elevation angles. Very fast fading is observed near the ends of a pass-over.

Dual-mode Antenna Tracking System for Rocket Launch Applications

Rocket launches are complex events that require tracking antennas to maintain a communication link. This study introduces a hybrid tracking strategy that combines manual and program modes by utilizing a predetermined trajectory of the rocket. Automatic switching between tracking modes ensures ongoing monitoring, even during unexpected trajectory changes with the monopulse approach. The dual parabolic antenna arrangement enables this switching. The system estimates the monopulse ratio from the signal strength of each antenna, allowing automatic program tracking to shift to manual mode when reception concerns arise. Performance evaluations included manual, programmable, and dual-mode tests. The system responded to human input and automatically aligned the antenna with slight elevation errors during the initial phase. Adjusting the initial elevation reduced the error. The mode transition was examined by measuring the antenna radiation patterns and monopulse ratio. The system’s performance was evaluated in rocket launches, with the rocket trajectory input into the graphical user interface. The antenna exhibited an azimuthal movement of up to 10 °, and the ratio fluctuation values remained within the antenna’s field of view. After 8.8 seconds, the mode switched from program to manual, indicating that the functioning of the system’s functioning was stable.

Rapid Tracking Satellite Servo Control for Three-Axis Satcom-on-the-Move Antenna

To overcome the possible gimbal lock problem of the dual-axis satcom-on-the-move (SOTM) antenna, a three-axis tracking satellite SOTM antenna structure appears. The three-axis SOTM antenna is realized by adding a roll axis to the azimuth axis and pitch axis in the dual-axis SOTM structure. There is coupling among the azimuth axis, pitch axis and roll axis in the mechanical structure of the three-axis SOTM antenna, which makes the kinematic modeling of the antenna difficult. This paper introduces a three-axis SOTM antenna kinematic modeling method based on the modified Denavit–Hartenberg (MDH) method, named the new modified Denavit–Hartenberg (NMDH) method. In order to meet the modeling requirements of the MDH method, the NMDH method adds virtual coordinate systems and auxiliary coordinate systems to the three-axis SOTM antenna and obtains the kinematic model of the three-axis SOTM antenna. During the motion of the carrier, the SOTM antenna needs to adjust the antenna pointing in real time according to the changes of the location and attitude of the moving carrier. Therefore, this paper designs a servo control system based on the active disturbance rejection controller (ADRC), introducing a smooth and continuous ADRC fal function to enhance the tracking speed of the servo control system and reduce the overshoot of the output response. Finally, system experiments were carried out with a 60 cm caliber three-axis SOTM antenna. The experiment results show that the proposed servo control method achieves higher antenna tracking satellite accuracy and better communication effects.

Comparison between CRONE and H∞ control approaches applied to tracking antennas

A mobile tracking antenna requires a precise control system that combines good trajectory tracking and disturbance rejection performances. The system has several operating scenarios, requiring robust control design that ensures good performances and stability degree for a set of uncertain models. This paper presents a comparative study between CRONE and H∞ robust controllers to assess the feasibility of applying these methodologies. A practical validation in antenna tracking demonstrates that both controllers yield equivalent results both in time and frequency domains, thus ensuring excellent stability and outstanding performances. The choice of controller ultimately depends on the designer’s expertise, software and/or hardware requirements, and the complexity of the system model.

Single Antenna Tracking and Localization of RIS-enabled Vehicular Users

Single Antenna Tracking and Localization of RIS-enabled Vehicular Users

A complete solution for anti-jaming radio data-link of an unmanned aerial vehicle

The effectiveness of an unmanned aerial vehicle's flight mission over a given distance depends on many factors. However, one of the key factors in the successful completion of a flight mission is the availability of high-quality management and control of telemetry by an unmanned aerial vehicle, which in turn is determined by a reliable radio communication between the ground control station and the unmanned aerial vehicle. The current stage of use of unmanned aerial vehicles is characterised by the use of active jammers of various types and purposes, the purpose of which is to disable control channels, navigation channels, telemetry channels and data transmission channels of FPV unmanned aerial vehicles in order to prevent the successful completion of the flight mission of the vehicle. The article considers conceptual issues of implementing a guaranteed interference-free radio data transmission and control of an unmanned aerial vehicle in the conditions of active jamming interference when combining various technological solutions. These solutions include the selection and justification of a special frequency range, the use of structural circuit solutions for interference protection of the radio data transmission and control line; the use of a specific scheme for organising communication with an unmanned aerial vehicle; the use of a transceiver and portable and light antennas for the radio channel that meet reasonable technical requirements; the implementation of the possibility of real-time monitoring of the interference situation on board the unmanned aerial vehicle and detection of the type of interference; ensuring flight in the sector. The requirements were justified and options for selecting a transceiver and antenna were proposed. A structural diagram of the radio line is developed and options for its use as a data transmission and control radio line for an unmanned aerial vehicle are proposed. Examples of real-time tracking of the interference situation on board an unmanned vehicle and detection of the type of interference are given. A flight option in the sector without the use of antenna tracking is calculated and justified. The approximate values of the signal at the receiver input of the unmanned vehicle are calculated.

Adaptive elliptic trajectory-based received signal strength indicator antenna tracking algorithm

The continuous telemetry transmission between unmanned aerial vehicles (UAVs) and ground control stations is important particularly in scenarios lacking global positioning system (GPS) data. This paper proposes an adaptive novel elliptic trajectory formula-based tracking algorithm for received signal strength indicator (ANETF-RSSI) which dynamically optimizes model parameters based on energy-associated RSSI measurement errors. ANETF-RSSI generates a variable two-dimensional (2D) RSSI map to identify optimal paths, even under challenging conditions like circular flight paths, varying operating ranges, and accelerated maneuvering, which causes uncertainty into RSSI measurements during flight. In contrast to previous methods, the proposed approach eliminates the reliance on telemetry data such as GPS or complex multiantenna configurations, ensuring robust UAV communication continuity across routes ranging from 100 m to 100 km, even as the UAV rotates around the antenna. This method offers substantial contributions, including enhanced monitoring precision, simplified hardware configurations, continuous tracking with superior accuracy, and adaptability to diverse range routes without the need for preflight parameter tuning. Performance evaluations demonstrate that the proposed ANETF-RSSI method consistently outperforms existing technique, improving nominal performance by 32.02% in the most challenging operational scenarios and achieving a remarkable 48.76% improvement in minimum RSSI values. Consequently, this research provides a versatile and adaptive tracking solution for unexpected UAV flight trajectories.

Antenna Tracker System for Unmanned Aerial Vehicles: A Short Review

<p class="Abstract">Unmanned Aerial Vehicle (UAV) is a modern technology used to perform difficult and dangerous aerial missions that cannot be carried out by manned aerial vehicles. Ground Control Station (GCS) is a system that manages all the parameters of the UAV. GCS and UAV communicate using radio waves through telemetry, which functions to transmit and receive flight data. Antenna tracker is a device used to connect the GCS (Ground Control Station) and the UAV (Unmanned Aerial Vehicle). The antenna tracker works by performing tracking to direct the antenna towards the UAV. Nowadays, there are various forms of antennas used in telecommunication technology. Each type of antenna has its own radiation characteristics, some are directional, while others are more omnidirectional. Directional antennas are the right choice to be used with an antenna tracker. Generally, directional antennas have a narrow radiation range but a relatively long transmission distance. This paper provides a review of the state-of-the-art in antenna tracker technology for unmanned aerial vehicles (UAVs), with a focus on design, performance, and type of antenna. The study involved a literature search of various databases. The design approaches for antenna tracker systems range from simple single-axis trackers to sophisticated dual-axis trackers with pan-tilt mechanisms, and type of antenna such as helical were explored. The study concludes that antenna trackers have numerous applications in various industries, including military, agriculture, and surveying, and the demand for reliable and accurate antenna trackers is expected to continue to grow with the increasing popularity of UAVs. </p><p class="Abstract"> </p><p class="Abstract"> </p><p class="Keywords"> </p>

The directional antenna tracker for enhancing range communication between UAVs and Ground Control Station

This paper discusses the development of an antenna tracker project focused on evaluating a 2.4 GHz Yagi Uda directional antenna connected to an NRF24L01 transceiver. It employs a gear reduction system for precise yaw and pitch control using two servo motors. The tracker calculates rotation angles using the Haversine formula for coordinates and inverse tangent trigonometry for elevation. Experiments took place in an open area with a stationary Ground Control Station (GCS) and a moving Unmanned Aerial Vehicle (UAV) to assess performance. The experiments comprised three tests: first, GCS without the Yagi Uda antenna or tracker; second, GCS with the Yagi Uda antenna but without the tracker, positioned along a 30-degree angle away from the transmitter; and third, GCS with both the Yagi Uda antenna and the tracker. The UAV gradually moved away from the tracker in 5-meter intervals until data loss occurred. The test results are based on received coordinates, distance, temperature, humidity, and data loss. Among the three tests, Test 3 demonstrates the best outcome, where the Yagi Uda antenna successfully receives data up to 180 meters before experiencing data loss.

A kinematic modeling scheme of three-axis "Satcom-on-the-Move" antenna based on modified Denavit-Hartenberg method

The current three-axes Satcom-on-the-Move(SOTM) antenna modeling method has some shortcomings, such as low model accuracy, poor portability and so on. In order to solve the above-mentioned shortcomings, a new modified Denavit-Hartenberg(NMDH) kinematics modeling scheme for the three-axes SOTM antenna was proposed. To overcome the modeling difficulties caused by the inherent mechanical structure of the antenna, and meet the requirements of the modified Denavit-Hartenberg(MDH) method, the virtual coordinate system and auxiliary coordinate systems are designed and added respectively on the basis of the MDH method, the forward kinematics model and inverse kinematics solution of the three-axes SOTM antenna are obtained. The correctness of the NMDH modeling scheme is verified by digital simulation. Finally, the system tests are carried out. The test results show that the NMDH modeling scheme proposed in this paper achieves good effect of antenna tracking satellite, and has stronger portability than the system identification modeling method commonly used in engineering.

2D-Localization Based on Tracking Antenna Using Artificial Intelligence Mapping (AIM) Approach

2D-Localization Based on Tracking Antenna Using Artificial Intelligence Mapping (AIM) Approach

CRONE multi-SISO control of a 2-axis tracking antenna

This paper presents an application of CRONE control, a robust control design based on fractional order differentiation, to a 2-axis tracking antenna. The controller will regulate the position of the two mechanical axes of the antenna: azimuth and elevation. To design the robust controller, a nonlinear model was developed to estimate the impact of uncertainties and mechanical coupling. A comparison between the CRONE controller and the current PI controller is presented. The experimental validation on the real antenna shows that the CRONE controller has better tracking performances while ensuring a high stability degree.

Research on Beam Waveguide Focus Phase Calibration Method of Deep-space TT&C System

The angle auto-tracking capability is needed in the deep space system, but in the sum-differential dual channels tracking model, the deep-space TT&C system must calibrate its phase before tracking a satellite. Because of the big aperture and high frequency of the deep-space TT&C system antenna, it is impossible to build a calibrating tower which satisfy the far-field condition, and the traditional phase calibration method relies on the tower is not suitable. The radio star calibration method selects a appropriate satellite as the calibrating signal source, but the signal of which is very weak and is affected easily. In this paper, the principle of phase calibration is analyzed, and the beam waveguide focus calibration method is studied, the processes of antenna tracking and angle error signal demodulation are given. The beam waveguide focus calibration method simulates the far field signal through controlling the position of horn antenna which is at the focus of the beam waveguide. The method can be realized easily in engineering, and the limit of the traditional calibration tower and the affections of the weather in using radio star calibration method are avoided.

Path Loss Investigation in Hall Environment at Centimeter and Millimeter-Wave Bands.

The millimeter-wave (mmWave) frequency is considered a viable radio wave band for fifth-generation (5G) mobile networks, owing to its ability to access a vast spectrum of resources. However, mmWave suffers from undesirable characteristics such as increased attenuation during transmission. Therefore, a well-fitted path loss model to a specific environment can help manage optimal power delivery in the receiver and optimal transmitter power in the transmitter in the mmWave band. This study investigates large-scale path loss models in a university hall environment with a real-measured path loss dataset using directional horn antennas in co-polarization (H–H) and tracking antenna systems (TAS) in line-of-sight (LOS) circumstances between the transmitter and receptor at mmWave and centimeter-level bands. Although the centimeter-level band is used in certain industrialized nations, path loss characteristics in a university hall environment have not been well-examined. Consequently, this study aims to bridge this research gap. The results of this study indicate that, in general, the large-scale floating-intercept (FI) model gives a satisfactory performance in fitting the path loss both in the center and wall side links.

Lower profile high‐power dual‐polarized wide‐beam tracking antenna at S‐band

AbstractAn S‐band dual linearly polarized monopulse tracking antenna has been developed with a cavity‐backed cross‐dipole antenna as the element. Wide‐beam and wideband tracking have been successfully demonstrated. Systematic design approaches have been presented. The cavity arrangement enhances the beamwidth of a horizontal dipole significantly retaining its wideband characteristics. The element exhibits a 3 dB beamwidth ≥145°. Such a wide beamwidth made the cavity‐backed cross dipole an attractive choice as the element for the tracking antenna. The monopulse antenna demonstrates an impedance bandwidth ≥20.7% with isolation superior to 24 dB. Dual polarized tracking has been effectively verified over ≥15% bandwidth with a broad‐side gain of 11.2 dBi. The angular field‐of‐view (FOV) for the tracking is ≥60°. Higher tracking bandwidth and wider FOV of the array, lower profile, and high‐power handling capability are the superiority of the developed antenna.

Effects of Integrated Fuzzy Logic PID Controller on Satellite Antenna Tracking System.

An electrical device that transforms the electricity into the waves of radio and vice versa is termed the antenna. Its main deployment is in the transmitter and receiver of the antenna. While transmission, the transmitter of radio at the extremities of the antenna furnishes the electricity which oscillates at the frequency of radio wave and energy is released as current as em waves. Some of the voltage is formed from the em wave that is invaded at the point of receiving to amplify the receiver. This study focuses on the analysis of the satellite system to aid in mobile antenna tracking. It also examines the techniques for fuzzy control which make up traditional networks that are used. Initially, a basic idea of tracking loops with stabilized antennas was suggested in light of the requirement for the margin of phase and bandwidth. If the gain of the track is reduced due to changes in attributes and throughput, it will be reduced. In addition, fuzzy regulators and PID constituents are used to enhance the loop. The results indicate that the higher and lower antenna tracking gains within the loop were the best fit and the loop's fluctuations are reduced. A controller based on fuzzy logic can be most efficient due to its simplicity and robustness. It is also discovered that fuzzy logic controllers are evaluated by their behavior in relation. This paper presents an evaluation of the controllers in fuzzy logic, which is based on its integration with conventional controllers. There are three gains in PID's regulator PID and every gain can be used to control the variables of inputs and outcomes. The effects of the responses were analyzed and were compared. The commonality was discovered in the results according to the increase in time for II/6 and II/3 based on PID's regulator PID stability, it can be improved by this system, and there is a reduction in the duration of stability. Furthermore, the period of stability may be reduced through the fusion of PID and fuzzy. The effectiveness of the system could be enhanced by the implementation of the neural network. It is also possible to design the two types of control that could be used to control the proposed solid platform.

Antenna Tracker Design With A Discrete Lyapunov Stability Based Controller For Mini Unmanned Aerial Vehicles

Communication systems have recently been very important in mini unmanned aerial vehicles (UAV), which include many research subjects. Directional antennas are generally used in communication systems, and they should continuously and efficiently follow the UAVs with minimal errors. For this purpose, an “Antenna Tracker” system, which is capable of real-time autonomous orientation based on GPS data from the UAV, was designed. In the beginning, the system’s 3-dimensional solid model was obtained in SOLIDWORKSTM and its dynamical model was made in MATLAB / SimulinkTM environment. For controlling the system, a discrete-time model-based computed torque proportional controller, which is the state-of-the-art innovation in this study, was designed in two axes, and then its simulation studies were conducted on the STM32 board. The simulation studies showed that controlling the pan and tilt axes is sufficient for effective tracking, and the presented antenna tracker system is suitable for use in mobile ground control stations (GCS). By using a short sampling time for the controller, stable and precise antenna tracking is accomplished for a given reference path. When a 0.5 Hz sinusoidal reference signal input which is the maximum speed for any antenna tracker was used as a sample reference track, ±0.3- and ±0.6-degrees position error of pan and tilt angles were obtained, respectively. The controller can easily satisfy a smooth tracking operation with high accuracy.

Robust control of 2-axis tracking antennas using the CRONE approach

This paper presents robust control design for a mobile tracking antenna using the CRONE approach. The antenna is modeled by two coupled mechanical axes used to track azimuth and elevation angles. The parametric uncertainties of the model and the axes mechanical coupling are taken into account in the design of the position loop controller. For comparison purposes, the same control specifications are applied for a PID controller. Simulation results show the effectiveness of the CRONE controller in terms of robustness and stability, as compared to the PID.

The Recent Advancement in Unmanned Aerial Vehicle Tracking Antenna: A Review.

Unmanned aerial vehicle (UAV) antenna tracking system is an electromechanical component designed to track and steer the signal beams from the ground control station (GCS) to the airborne platform for optimum signal alignment. In a tracking system, an antenna continuously tracks a moving target and records their position. A UAV tracking antenna system is susceptible to signal loss if omnidirectional antenna is deployed as the preferred design. Therefore, to achieve longer UAV distance communication, there is a need for directional high gain antenna. From design principle, directional antennas are known to focus their signal energy in a particular direction viewed from their radiation pattern which is concentrated in a particular azimuth direction. Unfortunately, a directional antenna is limited by angle, thus, it must always be directed to the target. The other limitation of a UAV mechanical beam steering system is that the system is expensive to maintain and with low reliability. To solve this problem, we are proposing the use of MIMO technology as a readily available technology for UAV beyond line of sight technology. Although UAV antenna tracking is domiciled in the mechanical beam steering arrangement, this study shows that this native technology could be usurped by MIMO beam forming.

Attitude stabilization of Marine Satellite Tracking Antenna using Model Predictive Control

Attitude stabilization is a necessary function for a shipboard Marine Satellite Tracking Antenna (MSTA), which is responsible for making the antenna dish track the geostationary satellite in the presence of severe environment. A control scheme based on Model Predictive Control (MPC) is proposed to stabilize the antenna dish of an MSTA, and the detailed design process from algorithm design to Hardware-in-the-loop (HIL) simulation is explained. Due to the use of stepper motor as the actuator, the MPC is proposed to deal with the speed acceleration and deceleration problems of stepper motors, which can result in the optimal velocity profile. The MPC algorithm is implemented in Field Programmable Gate Array (FPGA) with three different data types. In addition to using traditional floating-point and fixed-point data types to represent values in MPC, a special data type, half-precision floating-point, is also explored for the first time. The comparison results are presented and analyzed in terms of FPGA resource usage and algorithm execution time. The performance of the proposed control scheme is validated in HIL simulation, which is creatively implemented in a low-cost System On Chip (SOC) FPGA. The HIL simulation results demonstrate that the proposed control scheme in fixed-point MPC can satisfy the requirements of the MSTA.