Ground Control Unit Research Articles

Robust Multi-UAV Cooperative Trajectory Planning and Power Control for Reliable Communication in the Presence of Uncertain Jammers

Unmanned aerial vehicles (UAVs) have become a promising application for future communication and spectrum awareness due to their favorable features such as low cost, high mobility, and ease of deployment. Nevertheless, the jamming resistance appears to be a new challenge in multi-UAV cooperative communication scenarios. This paper focuses on designing trajectory planning and power allocation for efficient control and reliable communication in a ground control unit (GCU)-controlled UAV network, where the GCU coordinates multi-UAV systems to execute tasks amidst multiple jammers with imperfect location and power information. Specifically, this paper formulates a nonconvex semi-infinite optimization problem to maximize the average worst-case signal-to-interference-plus-noise ratio (SINR) among multiple UAVs by designing robust flight paths and power control strategy under stringent energy and mobility constraints. To efficiently address this issue, this paper proposes a powerful iterative algorithm utilizing the S-procedure and the successive convex approximation (SCA) method. Extensive simulations validate the effectiveness of the proposed strategy.

Joint Microwave and Millimeter-Wave Antenna Design for UAV-Enabled Communications

Wireless communications aided by unmanned aerial vehicles (UAVs) have emerged as a promising technology for serving numerous terminal devices of the Internet of Things (IoT). To support such a broad range of emerging applications, millimeter-wave (mm-Wave) is an effective solution because it has the characteristics of high transmission efficiency, wide frequency band, and very low latency. Meanwhile, a UAV-assisted communication system also requires a global positioning system (GPS) reception (1.575 GHz) and ground control unit (2.4 GHz). This paper investigates a highly integrated multi-band antenna design to operate at the microwave (μ-Wave) and mm-Wave bands for robust and flexible UAV communications. Each antenna operating band utilizes the technology of a substrate-integrated waveguide (SIW) cavity-backed antenna. By strategically engineering an mm-Wave antenna into a 2.4 GHz band antenna to share the aperture, besides showing high aperture reuse efficiency with a large frequency ratio, the proposed antenna has also maintained the geometrical advantages of compactness, planar configuration, and ease of integration with other circuits. Furthermore, the proposed antenna can provide flexible radiation patterns with upper/lower-space signal coverage according to the mission demands of the UAV. Experimental results of the prototype show that the antenna can fully cover the 1.575 GHz, 2.4 GHz, and fifth-generation (5G) mm-Wave bands of n257, n258, and n261. Multiple bands and stable radiation characteristics indicate the proposed antenna's suitability for deploying a UAV-supported wireless network.

Robust trajectory planning for UAV communication systems in the presence of jammers

Unmanned Aerial Vehicle (UAV) has emerged as a promising novel application for the Sixth-Generation (6G) wireless communication by leveraging more favorable Line-of-Sight (LoS) propagation. However, the jamming resistance by exploiting UAV’s mobility is a new challenge in the UAV-ground communication. This paper investigates the trajectory planning problem in an UAV communication system, where the UAV is operated by a Ground Control Unit (GCU) to perform certain tasks in the presence of multiple jammers with imperfect power and location information. To ensure the reliability of the GCU-to-UAV link, we formulate the problem as a non-convex semi-infinite optimization, aiming to maximize the average worst-case Signal-to-Interference-plus-Noise Ratio (SINR) over a given flight duration by designing the robust trajectory of the UAV under stringent energy availability constraints. To handle this problem efficiently, we develop an iterative algorithm for the solution with the aid of S-procedure and Successive Convex Approximation (SCA) method. Numerous results demonstrate the efficacy of our proposed algorithm and offer some useful designinsights to practical system.

Effective and Safe Trajectory Planning for an Autonomous UAV Using a Decomposition-Coordination Method.

In this paper, we present a Decomposition Coordination (DC) method applied to solve the problem of safe trajectory planning for autonomous Unmanned Aerial Vehicle (UAV) in a dynamic environment. The purpose of this study is to make the UAV more reactive in the environment and ensure the safety and optimality of the computed trajectory. In this implementation, we begin by selecting a dynamic model of a fixed-arms quadrotor UAV. Then, we define our multi-objective optimization problem, which we convert afterward into a scalar optimization problem (SOP). The SOP is subdivided after that into smaller sub-problems, which will be treated in parallel and in a reasonable time. The DC principle employed in our method allows us to treat non-linearity at the local level. The coordination between the two levels is achieved after that through the Lagrange multipliers. Making use of the DC method, we can compute the optimal trajectory from the UAV’s current position to a final target practically in real-time. In this approach, we suppose that the environment is totally supervised by a Ground Control Unit (GCU). To ensure the safety of the trajectory, we consider a wireless communication network over which the UAV may communicate with the GCU and get the necessary information about environmental changes, allowing for successful collision avoidance during the flight until the intended goal is safely attained. The analysis of the DC algorithm’s stability and convergence, as well as the simulation results, are provided to demonstrate the advantages of our method and validate its potential.

Efficient Resource Allocation for Multi-UAV Communication Against Adjacent and Co-Channel Interference

Unmanned aerial vehicle (UAV) swarm has emerged as a promising novel paradigm to achieve better coverage and higher capacity for future wireless network by exploiting the more favorable line-of-sight (LoS) propagation. To reap the potential gains of UAV swarm, the remote control signal sent by ground control unit (GCU) is essential, whereas the control signal quality are susceptible in practice due to the effect of the adjacent channel interference (ACI) and the external interference (EI) from radiation sources distributed across the region. To tackle these challenges, this paper considers priority-aware resource coordination in a multi-UAV communication system, where multiple UAVs are controlled by a GCU to perform certain tasks with a pre-defined trajectory. Specifically, we maximize the minimum signal-to-interference-plus-noise ratio (SINR) among all the UAVs by jointly optimizing channel assignment and power allocation strategy under stringent resource availability constraints. According to the intensity of ACI, we consider the corresponding problem in two scenarios, i.e., Null-ACI and ACI systems. By virtue of the particular problem structure in Null-ACI case, we first recast the formulation into an equivalent yet more tractable form and obtain the global optimal solution via Hungarian algorithm. For general ACI systems, we develop an efficient iterative algorithm for its solution based on the alternating optimization methods. Extensive simulation results demonstrate that the proposed algorithms can significantly enhance the minimum SINR among all the UAVs and adapt the allocation of communication resources to diverse mission priority.

PENGARUH KOMPETENSI, PENGALAMAN DAN BUDAYA KERJA TERHADAP KINERJA KARYAWAN DINAS TOWER DAN GROUND CONTROL MAKASSAR AIR TRAFFIC SERVICE CENTER (MATSC).

Influence of competence, experience and work culture concerning work performance of employe tower and ground control unit at Makassar Air Traffic Service Center (MATSC). The purpose of this research was to examine the influence of competence, experience and work culture concerning work performance of employe tower and ground control unit at Makassar Air Traffic Service Center (MATSC). Sampling methode used total sampling with 50 employe of air traffic controller who has valid of licence and rating related tower and ground control unit at Makassar Air Traffic Service Center (MATSC). The result of this research is indicate that there is a positif and significant relation of variable work culture and experience concerning employe working performance tower and ground control unit at Makassar Air Traffic Service Center (MATSC). While competence variable does not have signifacant relation concerning employe working performance tower and ground control unit at Makassar Air Traffic Service Center (MATSC). Keyword : competence, experience, work culture, work performance

Speed and position detecting systems for vehicle with linear synchronous motors

In high-speed ground transport linear synchronous motors are used to create a traction force. Advantages of linear synchronous motors are precise control of traction force (does not depend on friction forces) and lack of wearing parts. Linear synchronous motors control systems use block diagrams with orientation on rotor flux linkage. In such systems, information about exact position of movable part allows splitting active and reactive components of stator currents and as result independent control of motor traction force and magnetic flux. Errors in determination position can lead to errors in d-q transformation what affect calculations performed in motor model, and impact on traction force. Moreover, information on position of vehicle is also important to ensure traffic safety. In conventional types of wheeled vehicles for determining speed and position contact probes and tachometers are used. However, in high-speed magnetic levitation transport non-contact sensors is needed. In addition, when creating control system delay in transmission of radio signals from vehicle to ground control unit should be taken into account. This paper revive methods of speed and location detection for industry and high-speed ground transportation systems with linear synchronous motors. Also, variant of speed and position detection system for freight Maglev was suggested.

Fuzzy Control for a Kite-Based Tethered Flying Robot

Observation providing information from above is important in in large-scale or dangerous rescue activity. This has been done from balloons or airplanes. Balloon observation requires a gas such as helium and takes a relatively long time to prepare, and while airplane observation can be prepared in a relatively short time and is highly mobile, flight time depends on the amount of fuel a plane can carry. We have proposed and developed a kite-based tethered flying robot that complements balloon and airplane observation while providing a short preparation time and long flight time [1]. The objective of our research is autonomous flight information gathering consisting of a kite, a flight unit, a tether and a ground control unit with a line-winding machine. We propose fuzzy controllers for our robot that are inspired by kite flying.

2A1-F02 テザー係留型飛行ロボットのための大型地上制御ユニットの開発

2A1-F02 テザー係留型飛行ロボットのための大型地上制御ユニットの開発

Results from a comprehensive GPS Network: natural gas pipeline GPS Network

Developing the Nabucco engineering infrastructure was the most challenging task imaginable and required state-of-the-art technologies. For this purpose, a Nabucco-Global Positioning System (GPS) Network was established. It is 762 km long. Nine-hundred and two ground control unit points were established. In order to provide the relationship with ITRF96 datum, it was surrounded by TFNGN (Turkish Fundamental National GPS Network) and TNVCN (Turkish National Vertical Control Network) checkpoints. GPS observations were evaluated in the form of a unique network. After being reduced to projection segments, coordinates in ED50 datum were provided between datums by 2D-Helmert Transformation. Orthometric heights related to the GPS Network were obtained by the improvement of TG-03 data based on a GPS/leveling procedure. The objective of the study is to present the results of a comprehensive engineering project which involved many geodetic considerations including GPS, orthometric heights, and geoid undulations and gives insight into the accuracy and precision of such large projects in terms of recent geodetic practice. In this study, a Global Navigation Satellite System (GNSS)-based geodetic infrastructure is presented, methods to obtain the necessary precision requirements are provided, and experience is shared in order to provide an example of a large-scale pipeline project, and to provide insight into the planning necessary for future similar engineering projects.

Automatic Positioning Control System of Train

A type of automatic positioning control system of train has been introduced. The key element of system is based on induction radio communication technology. System is composed of four parts: ground control unit, communication unit, train control unit and external control part. The carrier of position produced by generator is amplified and sent to the coded flat cable. Then the signal is induced by antenna of train. Through control unit of train, the location of train will be gained. The location signal is sent out to PLC control part which will control some external equipment. It is especially for real-time address detecting online of subway or light rail trains during running. Several functions of automatic stop, positioning, opening, closing and others have been achieved in this control system.

Performance analysis of cooperative multi‐carrier relay‐based UAV networks over generalized fading channels

AbstractThe outage probability in a network of cooperative unmanned airborne vehicles (UAVs) over generalized fading channels is studied analytically using finite mixture with expectation maximization technique. A relay‐based topology with one ground control unit (GCU) is considered, where the cooperative UAVs can communicate with the GCU directly or through relay. The application the UAV is assigned for specifies the minimum required transmission rate the UAV should achieve. The outage probability of the system is defined as the probability that either the transmission rate over any of the links drops below a predefined minimum threshold for that link or the Relay‐GCU link is not able to transmit the aggregate data from all relayed UAVs and the minimum rate required by the relay UAV itself. Throughout the paper, expressions for the outage probability and the average achievable bit rate of a cooperative multi‐carrier system are derived over generalized fading channels. Finite mixture with expectation maximization algorithm is utilized to derive a simple approximate expression for the probability density function (pdf) of the achievable bit rate assuming adaptive M‐ary quadrature amplitude modulation (M‐QAM). This pdf is used to derive closed‐form expressions for the outage probability and the average bit rate. Copyright © 2011 John Wiley & Sons, Ltd.

Design of Monitoring System on Pulley Car

A type of design method of monitoring system on pulley car is introduced. The system is composed of car control unit, ground control unit, communication unit and computer management unit. The key element of system is based on induction radio communication technology. The position of pulley car can be detected dynamically by following hardware and software unit. At the same time, the signal of position is sent to host linked. By watching animation of pulley car, workers standing in workroom can know the position of pulley car accurately at any moment.

Development of a test-bed to implement and validate real-time control strategies for aerial vehicles

AbstractNowadays, there exist several platforms or experimental prototypes of aerial vehicles, most of them being specific for certain applications. The implementation of the control laws is, in most cases, restricted to given criteria and pre-established conditions defined by the commercial system (or the builder). In this paper, a new generic platform operating under Linux-RT, XtratuM and Partikle systems is introduced. Analyze, evaluate and improve the performance of future control embedded systems are the goals of the proposed platform. The platform is composed of a ground control unit (GCU) and an aerial system. In order to validate the platform, some experiments stabilizing the orientation and the altitude of the aircraft have been executed in free flight. The experimental results show the good performance and the robustness of the proposed control scheme.

Microcontroller based ground weapon control system(Short Communication)

Armoured vehicles and tanks generally consist of high resolution optical (both infrared and visible) and display systems for recognition and identification of the targets. Different weapons/articles to engage the targets may be present. A fire control system (FCS) controls all the above systems, monitors the status of the articles present and passes the information to the display system. Depending upon the health and availability of the articles, the FCS selects and fires the articles. Design and development of ground control unit which is the heart of the FCS, both in hardware and software, has been emphasised. The system has been developed using microcontroller and software developed in ASM 51 language. The system also has a facility to test all the systems and articles as initial power on condition. From the safety point of view, software and hardware interlocks have been provided in the critical operations, like firing sequence.