- Wireless IoT Communication Module with Low Power Consumption for a Soil Moisture and Salinity Sensor
Adrian Łostowski, Arkadiusz Lewandowski and Michal Abramowicz (Warsaw University of Technology, Poland); Andrzej Wilczek and Agnieszka Szypłowska (Institute of Agrophysics, Polish Academy of Sciences, Poland); Marcin Kafarski (Institute of Agrophysics, Polish Academy of Sciences & The State School of Higher Education in Chełm, Poland); Wojciech Skierucha (Institute of Agrophysics, Polish Academy of Sciences, Poland)
The purpose of this work was to create a wireless Internet-of-Things (IoT) communication module for a device for measuring soil parameters in a field environment. The module uses the Low Power Wide Area Network (LPWAN) technology to exchange data with an external database. This paper contains information about design assumptions, research on the existing long-range communication technology solutions and description of the design process.
- Determining a Matched Load Response of Six-Port Reflectometer Using Partially Known Calibration Loads
Kamil Staszek (AGH University of Science and Technology, Poland)
This paper presents a method for determining a six-port reflectometer's response to a matched load with the use of partially known calibration loads. It utilizes nine calibration loads which can be of unknown magnitude and phase, however, three of them must exhibit magnitudes possibly close to each other with a reasonable phase separation. The algorithm was tested with the use of an exemplary broadband six-port reflectometer operating over the frequency range from 2.5 GHz to 3.5 GHz. The power values obtained using the proposed method are very close to those directly measured by the six-port reflectometer with a broadband matched load from precision calibration kit connected as DUT.
- Estimation of Comb Structure Capacitance for MEMS Inertial Sensors
Jacek Nazdrowicz and Adam Stawiński (Lodz University of Technology, Poland); Andrzej Napieralski (Technical University of Lodz, Poland)
In this paper authors presents very important problem of estimation capacitance structures used in MEMS sensors. The importance comes from fact that during operation, inertial sensors which are build of solid materials deform because of external forces acting on them. Therefore typical capacitor consists of some electrodes changes its value because electrode changes its orientation. Here authors use analytical and FEM results to compare capacitance results and impact on accuracy of measurement.
- Geometry Details of Inertial Microsensors Influenced on Their Performance
Jacek Nazdrowicz and Adam Stawiński (Lodz University of Technology, Poland); Andrzej Napieralski (Technical University of Lodz, Poland)
In the paper authors take into considerations results of analysis both MEMS accelerometers and gyroscopes under performance that can be changed by some geometry details modifications. Authors considers different types of shapes of springs to show, how they influence on total device operations.
- Integrated Correlator with Rat-Race Hybrids for the WiFi Band Quadrature Microwave Frequency Discriminator
Adam Rutkowski (Military University of Technology, Poland); Hubert Stadnik (Military University of Aviation, Poland)
The instantaneous frequency measurement (IFM) devices are very useful for very fast measurement of current frequency value of microwave signals even if their duration is extremely short. A fast measurement of temporary value of frequency is based on evaluation of a phase difference of signals propagating through the microwave transmission lines having unequal but known lengths. This phase difference is provided by so-called proportional phase shift forming network (PPhSFN), and the phase difference measurement is performed by the microwave phase discriminator (MPhD). The main segment of MPhD is a microwave six-port made of several microwave splitters and combiners. The paper presents integrated version of microwave correlator containing PPhFS and six-port on a single printed circuit board (PCB). The developed device was designed to work over WiFi frequency range. The frequency bandwidth of the made correlator reaches nearly one octave.
- The Performance Analysis and Optimization of IGLUNA 2019 Lunar-Analogue Longwave Transmitting System
Tomasz Aleksander Miś (Warsaw University of Technology & Institute of Radioelectronics and Multimedia Technology, Poland)
The paper presents the attempt of finding optimal solutions regarding the emission type, basic emission parameters and channel capacity for the trans-ice longwave communication channel, as deployed in June 2019 during the first edition of the IGLUNA programme - a simulated lunar habitat in the Klein Matterhorn glacier in Switzerland. The experimental system is compared to lowland high-power longwave systems, the optimal emission type for different conditions (modulation index, demanded presence of carrier) is presented and the maximum possible channel capacity in relation to the achieved signal readability is calculated.
- Analysis on Damage Efficiency of High Power Microwave to Marine Navigation Radar
Zeyu Xin (Naval Research Academy, China)
High power electromagnetic pulse weapon (EMP) is a new kind of weapon which can directly transmit high power microwave to damage the target electronic equipment. This paper introduces the damage mechanism of high power microwave, describes the working principle of the marine navigation radar and the front-end structure of receiver. The damage ability of high power microwave to marine navigation radar receiver is calculated and analyzed, at the same time, the damage range of high power microwave to marine navigation radar is given under the different states of power center and power edge.
- An Additive Manufactured K-Band Waveguide Coupler and K-Band Antennas in SLM-Technology
Christopher Beck and Jasmin Gabsteiger (Friedrich-Alexander-University Erlangen-Nuremberg, Germany); Marco Dietz (Friedrich-Alexander-University Erlangen-Nuremberg & Institute for Electronics Engineering, Germany); Christian Scheitler (Friedrich-Alexander-University Erlangen-Nuremberg, Germany); Robert Weigel (Friedrich-Alexander Universität Erlangen-Nürnberg, Germany); Amelie Hagelauer (University of Bayreuth, Germany)
3D printing offers a very innovative opportunity for creating cheap or special rf-components like waveguides, couplers or antennas. However, these components require electrical conductive
materials to be built of. Therefore, selective laser melting of metal powder is also an attractive production technology. In this paper, horn antennas and a directional coupler at 24 GHz are shown
and their production technologies are compared. By presenting a K-band branchline coupler it is shown that selective laser melting has some advantages over 3D printing.
- Passive Acoustic Radar System for Flying Vehicle Localization
Yevhen Chervoniak, Rustem Sinitsyn and Felix J Yanovsky (National Aviation University, Ukraine)
The proposed radar system is characterized by cheap equipment (omnidirectional microphones, a computer for signal processing, and peripherals) and by the special algorithm of signal processing, which has been developed and tested during full-scale experiments with real targets: aircrafts and UAVs. A key feature of the developed algorithm is a fast method of estimation of wideband ambiguity function. In addition, the algorithm provides visualization of the target location process using the projection of the ambiguity function onto a coordinate plane. The developed radar system is proposed to use for aircraft noise management in the vicinity of an airport and for localization of small-sized flying vehicles. The results of the experiments are presented in the paper
- The IoT Weightless System Vulnerability to Jamming - a Measurement-Based Case Study
Kamil Staniec (Wroclaw University of Science and Technology, Poland); Michał Kowal (Wrocław University of Science and Technology)
the Weightless(-P) is a narrowband communication system designed for the Internet of Things, along with some other counterparts such as Lora and SigFox. As a system dedicated specifically for long-range operations, it possesses a considerable processing gain for the energetic link budget improvement and a remarkable immunity to multipath and interference. The paper describes outcomes of measurement campaign during which the Weightless(-P) performance was tested against variable interference, generated in an anechoic chamber. Results allow to quantitatively appraise the system behavior under these harsh conditions with respect to the modulation and the resultant bandwidth. The outcomes allowed to propose recommendations regarding the use of particular system settings to optimally fit environmental conditions. Finally, the paper provides an analysis in which CNIR is converted to the Interference Margin and its value is checked against an intentional jammer approaching the base station to verify how different Weightless operational modes respond to electromagnetic jamming.
- An Efficient Simulation Method of Massive MIMO Antenna Arrays Used in 5G Mobile Phones
Damian Szypulski (Gdansk University of Technology, Poland); Grzegorz Fotyga (Gdańsk University of Technology, Poland); Michal Mrozowski (Gdansk University of Technology, Poland)
This paper deals with a model-order reduction method, applied to speed-up the simulations of MIMO antenna arrays, performed by means of finite element method. The obtained results of the numerical tests show that the described technique is reliable and considerably increases the efficiency of the standard finite element method.
- Radar-based Detection of Birds at Wind Turbine Installations: Results from a Field Study
Jochen Moll, Ashkan Taremi Zadeh and Moritz Mälzer (Goethe University Frankfurt am Main, Germany); Jonas Simon (Goethe-University Frankfurt, Germany); Viktor Krozer (Goethe University of Frankfurt am Main, Germany); Christian Kramer, Herbert Friedmann and Andreas Nuber (Wölfel Engineering GmbH + Co. KG, Germany); Manfred Dürr (Volta Windkraft GmbH, Germany); Dimitry Pozdniakov (Hubner Germany, Germany); Rahmi Salman (HF Systems Engineering GmbH & Co. KG & Hübner Holding GmbH, Germany)
Radar technology in the mm-wave frequency band
is a promising approach for the detection of birds and bats at
wind turbine installations in order to reduce fatalities either by
direct collision of the animals with the rotor blades or through
barotrauma. In this paper we present an FMCW radar system
with 1 Tx and 9 Rx operating in the Ka-band from 33.4 GHz
to 36.0 GHz. The radar system is installed at the tower of a
2MW wind energy plant about 95m above ground. The data
acquisition is described in this paper including the real-time
processing pipeline, followed by exemplary bird detections. Also
the detection of drones, serving here as an artificial flying object
with a defined flight path, will be presented and discussed.
Validation is performed by concurrent camera recordings.
- Microwave Radiometer Against of the Stealth
Oleksandr Denisov (Harbin Institute of Technology, China)
The specially calculated reflecting surfaces with Stealth invisible quality designed for to avoid vertical ones for ra-dar beam and to reflect beam "to the milk".
Stealth coatings with the full absorption of the micro-wave radar radiation on his surfaces are blackbody and reasonable to consider it as the matched loading with the corresponding physical outside temperature.
A lot of news and minding has place about the Stealth application especially in the contest of an airplanes. Possi-bility to avoid the disclosing of an airplane on the big dis-tances is main advantage of this Stealth "addition" against of the radars. But in much cases for the microwave radi-ometers this Stealth coating can be good for the real deter-mination by the passive devices because their job based on the measuring the radio-brightness contrast between Stealth objects and the background of the environment/s (sky is cold, Earth is warm).
The aim of this short report - to present some under-standing about to use radiometer about Stealth objects
- Influence of Dielectric Overlay Permittivity on Size and Performance of Miniaturized ESPAR Antenna
Mateusz Czelen (Gdansk University of Technology, Poland); Mateusz Rzymowski (Gdansk University of Technology & WiComm Center of Excellence, Poland); Krzysztof Nyka (Gdansk University of Technology, Poland); Lukasz Kulas (Gdansk University of Technology, Faculty of Electronics, Telecommunications and Informatics, Poland)
In this paper, influence of dielectric overlay permittivity on miniaturized ESPAR antenna parameters is presented. ESPAR antenna is a low-cost and energy-efficient way to implement beam steering capability to a node and improve network performance. The antenna size reduction is obtained by embedding its active and passive elements in ABS based materials of relative permittivity equal to 4, 5.5 and 7.5 in order to achieve network node compact size. Simulation results of three optimized for particular dielectric constant designs are presented and tradeoff between dimensions reduction and performance is discussed. Selected materials and antenna design are dedicated to be fabricated in 3D print technology, so can be easily prototyped.
- Influence of Salt Mist on Microwave Propagation
Bing Zhang, Wenyi Zhang, Zhuo Chen, Fuyu Luo and Haibin Zhou (Systems Engineering Research Institute, China)
Microwave propagation in the atmosphere is affected by air temperature, humidity, attitude, and other factors, there are many related researches on the above influencing factors, but relatively few researches are attached on the microwave propagation characteristics under the condition of sea salt mist. It is of great significance to clarify the law of microwave propagation attenuation under the condition of salt mist for the microwave applications such as maritime communication and radar detection. Firstly, the parameters of the salt mist environment are analyzed and modeled in this paper, and it is driven that the relationship between the concentration of the salt mist and the dielectric constant of the atmosphere. Then, based on the FDTD numerical analysis, the microwave propagation law under different concentration of the salt mist is calculated and compared with the theoretical analysis results.
- Experimental Setup with a Compact Vector Network Analyzer, RGB-D Sensor, and Linear Drive Modules for Imitation Modeling of Microwave Personnel Screening System in Motion
Andrey Zhuravlev (Bauman Moscow State Technical University, Russia); Ge Dong (Tsinghua University, China); Vladimir Razevig (Bauman Moscow State Technical University, Russia); Margarita Chizh (Bauman Moscow State Technical University & Remote Sensing Laboratory, Russia)
This paper describes an experimental setup that was built to imitate the performance of the new microwave personnel screening system, in which synthetic aperture is formed due to relative motion of the subject in the vicinity of a sparse antenna array. The RGB-D sensor captures a color image and a depth map of a still scene with a mannequin, while the compact network analyzer, which is moved by a two-dimensional scanner, acquires the samples of the radar signal reflected from the same scene. The mannequin is moved by the third linear drive module to another position, creating the next still scene to be scanned and captured similarly during a single experiment. The collected data is stored for the following joint processing. Preliminary radar images of concealed objects on mannequin are obtained and demonstrated. The use cases of the experimental setup are described toward designing a sparse electronically switched antenna array: finding the required number of the channels, choosing proper frequency band and bandwidth, antenna type, and others.
- Novel Algorithm for Position Estimation of Handheld Ground-Penetrating Radar Antenna
Piotr Kaniewski and Tomasz Kraszewski (Military University of Technology, Poland)
The paper presents an algorithm for positioning of a handheld ground-penetrating radar antenna. The algorithm has been elaborated for processing range measurements in a currently developed positioning system based on ultrawideband radio modules. Such a system is planned to be used as a support for a handheld ground-penetrating radar as continuous and accurate positioning of its antenna can facilitate creation of high-quality subsurface images. The paper contains a short description of the developed system and focuses on its Kalman filter used for positioning. Here, we consider using a novel dynamics model, based on a pendulum motion model, which provides a more adequate description of the antenna's dynamics than abstract position-velocity or position-velocity-acceleration models, commonly used in navigation systems. Chosen simulation results which support this claim are presented.
- An X-Band FMCW Radar Demonstrator Based on an SDR Platform
Grzegorz Dąbrowski (Warsaw University of Technology, Poland); Krzysztof Stasiak (Warsaw University of Technology); Jedrzej Drozdowicz, Damian Gromek and Piotr Samczynski (Warsaw University of Technology, Poland)
The paper presents an implementation of analog front-end designed for use in an X-band Frequency Modulated Continuous Wave (FMCW) radar system. Fine range resolution is achieved because of using more than 1 GHz of bandwidth, which is achieved through application of frequency multipliers. The system has been tested in laboratory as well as in a real environment using a USRP (Universal Software Radio Peripheral) device for both, waveform generation and beat signal digitization.
- Running Gaussian Average as Method of Adaptive Background Subtraction in Radar Applications
Boris Levitas (Geozondas Ldt., Lithuania); Michail Drozdov (Engineer, Lithuania)
Background subtraction is usual step in impulse radar applications. It is used to not only remove clutter - reflections of all the stationary, mostly irrelevant objects, but also crosstalk. Various techniques are used for clutter/crosstalk removal. These are briefly over-viewed. Focus of this paper, however, is on proposed method of adaptive background subtraction, which is statistical real time method based on developments of entirely different field (Computer Vision)
- Non-Destructive Testing of the Rails Rolling Surface and Joints with Synthetic Aperture Radar
Margarita Chizh (Bauman Moscow State Technical University & Remote Sensing Laboratory, Russia); Andrey Zhuravlev and Vladimir Razevig (Bauman Moscow State Technical University, Russia); Sergey Ivashov (5, 2nd Baumanskaya str., Russia & Bauman Moscow State Technical University, unknown)
This paper explores the possibility of using a synthetic aperture radar to detect surface defects of rails and measure parameters of rail junctions. Experimental data were obtained with a setup consisting of a two-coordinate electromechanical scanner and a radar emitting continuous stepped-frequency signal in the range of 22.2 - 26.2 GHz. As an object of study, fragments of narrow-gauge rails were used, in which surface defects of various sizes and depths were created. A phase method for radar signal processing based on the backward propagation of its wavefront was developed, with which radar images of rails with defects were obtained.
Experimental studies have shown that the developed rail surface imaging method allows detecting the presence and measuring characteristics of cracks on the tread, cleavages of the railhead, the width of the joint gap and the magnitude of the vertical step at the rails joint. High accuracy and sensitivity of the radar method, confirmed with the contact measurements matching, allow using it for fast noncontact diagnostics of the rails condition.
- Building Extraction from PolSAR Image Based on Deep CNN with Polarimetric Features
Xiaofang Xu (Harbin Institute of Technology, Singapore); Yilong Lu (Nanyang Technological University, Singapore); Bin Zou (Harbin Institute of Technology, China)
For polarimetric synthetic aperture radar (PolSAR) images, building extraction has been a challenging topic for long time in applications of land-use and land-cover analysis. Due to similar structures of buildings and such vegetation as forest, they often exhibit similar PolSAR scattering characteristics that are often difficult to distinguishing. Recently, deep Convolutional Neural Network (CNN) has been widely investigated for image processing with many promising results. This paper proposes a method that combines polarimetric features with the CNN network to realize the comprehensive utilization of polarimetric and contextual information of PolSAR data for the extraction of building areas in PolSAR images. Comparison experiments on both ESAR and EMISAR L-band PolSAR datasets show that the proposed method can generate better results for building extraction.
- Ground Moving Target Parameter Estimation and Track Reconstruction of Single-Channel CSAR
Jianpeng Li (National University of Defense Technology, China); Daoxiang An, Beibei Ge, Wu Wang, Leping Chen and Zhimin Zhou (National University of Defense Technology, China)
Recently, Interest on circular SAR (CSAR) has been increased in researchers. The sub-aperture division and trajectory reconstruction of ground moving target are important parts of the CSAR research. Firstly, the CSAR sub-aperture is fitted by a second-order curve, which achieves better focusing quality than the traditional fitting method. Next, parameter estimation accuracy is improved of each CSAR sub-aperture. Finally, the trajectory of ground moving target is reconstructed. Simulated data are used to prove the effectiveness and correctness of the proposed method.
- An Effective Method of Bridge Detection Based on Polarimetric CSAR
Xiangcheng Tan, Daoxiang An, Leping Chen, Yuxiao Luo and Zhimin Zhou (National University of Defense Technology, China); Dizhi Zhao (Southwest China Research Institute of Electronic Equipment, China)
This paper introduce an approach for detecting bridges when the difference in radar echo energy is not obvious. It consists of two steps: extracting targets with high anisotropy and detecting bridge. Firstly, by image segmentation based on the feature of multi-aperture polarimetric entropy, we get targets with high certainty. And then we utilize edge detection to extract straight line segmentations. Finally, the parallel straight line segmentations which meet the bridges' geometric properties are selected as bridges. The proposed approach has been test with polarimetric CSAR data, and the experimental results show that our method can detect bridges effectively.
- Novel ISAR Range Alignment via Minimizing Entropy of the Sum Range Profile
Yuan Liu and Lu Wang (Nanyang Technological University, Singapore); Hongwei Liu (National Laboratory of Radar Signal Processing, China); Hui Bi (Nanjing University of Aeronautics and Astronautics, China); Guoan Bi (Nanyang Technological University, Singapore)
A novel global range alignment technique for inverse synthetic aperture radar (ISAR) imaging is presented in this paper. Instead of requiring the parametric model for the relative offset amongst the range profiles, the alignment is investigated from the viewpoint of optimization, where the minimization of the entropy of the sum range profile (SRP) is employed as the optimization criterion. The precise range alignment within a range cell can be achieved by implementing the proposed algorithm. With respect to the existing global method, the proposed one does not require any interpolation operation and multidimensional search operation. Experimental results based on real measured data of maritime non-cooperative target validate the effectiveness and the efficiency of the proposed algorithm.
- Lq-norm Regularization Based SAR Image Feature Enhancement
Hui Bi, Jiarui Deng, Liping Wang and Jie Yin (Nanjing University of Aeronautics and Astronautics, China); Guoan Bi (Nanyang Technological University, Singapore)
In this paper, a general iterative thresholding algorithm (ITA) for solving Lq-norm regularization problem is proposed to achieve the synthetic aperture radar (SAR) image feature enhancement. Compared with the reconstructed images by matched filtering (MF) based method, the proposed method recovered images have lower sidelobes, reduced noise and clutter, which improves the image quality effectively. Experiments basedon Gaofen-3 (GF-3) SAR complex image data are used to validate the proposed method.
- Study on Motion Compensation Method for W-Band UAV MISAR Real-Time Imaging
Hui Wang (Key Laboratory of Millimeter Wave Imaging Technology & Shanghai Institute of Satellite Engineering, China); Zhaoyang Zeng (Shanghai Insititute of Satellite Engineering, China); Man Jiang and Shichao Zheng (Shanghai Academy of Spaceflight Technology Beijing R&D Center)
A real-time imaging right side-looking synthetic aperture radar (SAR) motion error model is established in this paper, and a center beam motion compensation algorithm based on inertial navigation and phase gradient autofocus (PGA) motion error estimation is adopted. The algorithm compensates the echo envelope and phase separately, and uses the inertial navigation data to straighten the echo envelope with motion error, and then uses the phase gradient autofocus algorithm to estimate and compensate the phase error of the echo. In view of the characteristics of real-time imaging, such as short time, large amount of computation and limited computing resources, the algorithm cancels the steps of range migration correction, projects the motion error vector on the slant plane, and completes envelope correction and phase error estimation. The method has a small amount of calculation and can meet the resolution requirement. The simulation results show that it can obtain high quality SAR images.
- Target Tracking in Blind Range of Radars with Deep Learning
Chandrakanth V (Defense Research and Development Organization, India)
Surveillance radars form the first line of defense
in border areas. But due to highly uneven terrains, there are
pockets of vulnerability for the enemy to move undetected till
they are in the blind range of the radar. This class of targets are
termed the 'pop up' targets. They pose a serious threat as they
can inflict severe damage to life and property. Blind ranges occur
by way of design in pulsed radars. To minimize the blind range
problem, multistatic radar configuration or dual pulse trans-
mission methods were proposed. Multistatic radar configuration
is highly hardware intensive and dual pulse transmission could
only reduce the blind range, not eliminate it. In this work we
propose, elimination of blind range using deep learning based
video tracking for mono static surveillance radars. Since radars
operate in deploy and forget mode, visual system must also
operate in a similar way for added advantage. Deep Learning
paved way for automatic target detection and classification.
However, a deep learning architecture is inherently not capable of
tracking because of frame to frame independence in processing.
To overcome this limitation, we use prior information from past
detections to establish frame to frame correlation and predict
future positions of target using a method inspired from CFAR
in a parallel channel for target tracking.
- The Performance of a Linear STAP Processor for Radar Signal Processing
Anna Ślesicka and Adam Kawalec (Military University of Technology, Poland)
Space-Time Adaptive Processing (STAP) enables detection of a moving object against the background of strong interference by radar. The fundamental principles of the STAP technique for radar signal processing in particular, detecting slow moving objects against interference. are presented in this paper. The parameter (improvement factor), determining the performance of any linear processor was analysed.
A disturbance model has been proposed, for which the dependence determining the performance of any STAP processor has been derived. The results of simulation of the optimal processor performance against the suboptimal processor for three different values of noise to interference ratios in reference channels were presented in the paper.
- Some Remarks on Maximum Likelihood Estimation in Alpha-Stable Environment
Zbigniew Gajo (Warsaw University of Technology, Poland)
This paper concerns the problem of maximum likelihood (ML) estimation in the case of impulsive observations modeled by heavy-tailed α-stable distributions. To describe analytically the cost function in ML estimation criterion the Fox function representation of α-stable distributions is used.
- Experimental Evaluation of PA Digital Predistortion Based on Simple Feedforward Neural Network
Dawid Rosolowski and Konrad Jędrzejewski (Warsaw University of Technology, Poland)
The paper presents the results of experimental studies on evaluation of employing digital predistortion based on simple feedforward neural network for linearization of microwave power amplifiers. The influence of the number of neurons in the hidden layer, the number of delayed input samples at the input of neural network, as well as the number of samples taken for learning a neural network were studied and discussed in the paper. The main goal of this work was to establish the minimal configuration of the neural network which can be used for linearization of power amplifiers excited by wideband and high PAPR signals, e.g. LTE. The results obtained for neural networks were compared with the results obtained for the conventional predistortion method based on memory polynomial.