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A magnetron is a power oscillator device used in several radar transmitters for generating the electromagnetic wave (EMW) with a constructive and fixed frequency. In this work, a radar transmitter has been carried out using magnetron operates at 2,458 MHz and two conducting layers waveguides to achieve minimum loss of the signal due to the increased temperature. The magnetron is connected with the high voltage capacitor (1.0 μF) in order to store the alternating current (AC) signal delivered from the high voltage transformer. A waveguide parts have been used as transmission lines in view of connecting the magnetron to the antenna. These parts include two metal layers, the upper layer (outer) is advanced audio coding (AAC) 1350 aluminum conductor and the lower (inner) is copper. The waveguide dimension should be suitable to flow frequency from 2.2 GHz to 3.3 GHz. To measure the operating frequency, a waveguide adapter and a coaxial cable which combined with n-female connector have been connected to magnetron. The wave is delivering to the frequency counter by Bayonet Neill–Concelman (BNC) to n-female connectors. The promising results of the proposed work have been achieved with a maximum power, efficient return loss, acceptable voltage standing wave ratio (VSWR) and low-cost manufacturing.

For military and civilian applications, synthetic aperture radar (SAR) imaging is an essential instrument for obtaining images of the Earth's surface. Speckle noise, a form of noise that is multiplicative, generated by conflicting echoes returned from each pixel, has a significant impact on the SAR picture. On SAR pictures, a hybrid filter for mixed noise reduction is used to remove the mixed noises that are present in the data during capture and transmission. Specifically, speckle noise and salt and pepper noises from SAR images. Both are being worked on at the same time to minimize mixed noise in SAR pictures without revealing edges or other features. This study proposes a technique that combines a hybrid filter derived from a statistics filters with nonlinear functions (SFNF). When comparing to mean, median as no adaptive filters, and frost filter, a lee filter, and fuzzy filters as adaptive filters, this hybrid filter produces good results. MATLAB was used to carry out the simulation. To illustrate the filtering technique's performance, quantitative measurements like signal to noise ratio (SNR) procedure, the mean square error (MSE) method, and edge measurement (β) mechanization are used.

The following paper presents a developed design and manufacturing of a servo-driven Electromechanical high-temperature tensile machine with an integrated environmental chamber. The maximum load capacity is set to be 20 kn with the possibility of future upgrades. The machine is automated by a computerized system that controls the entire operation of the designed machine. It is designed to be capable for testing a variety of materials at various temperatures ranging from room temperature up to 500℃. The machine was fully controlled using automated software to control the entire operation and to provide users with a certified test report. The main component is a high-quality aluminum frame that hosts the entire setup, like a furnace, and a universal type gripping mechanism. The structure is monitored by precise measurement instrumentation and a dependable data acquisition system. The machine was validated by testing AA6063-T6 to evaluate the sophistication of the machine's functionality. The results then compared to an international standard, provided close results with a low percentage error of about 4.5% compared to international standard readings.

In this paper, a new compact coplanar antenna used for Radio frequency identification (FID) applications is presented. This antenna is operated at the resonant frequency of 2.45 GHz. The proposed antenna is designed on an epoxy substrate material type (FR-4) with small size of (40 × 28) mm2 in which the dielectric thickness (ℎ) of 1.6 mm, relative permittivity (er) of 4.3 and tangent loss of 0.025. In this design the return loss is less than −10 dB in the frequency interval (2.12 − 2.84) GHz and the minimum value of return loss is -32 dB at resonant frequency. The maximum gain of the proposed antenna is 1.22 dB and the maximum directivity obtained is 2.27 dB. The patch and the ground plane of the proposed antenna are in the same surface. The proposed antenna has a wide bandwidth and omnidirectional radiation pattern with small size. The overall size of the compact antenna is (40 × 28 × 1.635) mm3. The Computer Simulation Technology (CST) microwave studio software is used for simulation and gets layout design.

A modified mixed Gaussian plus impulse image denoising algorithm based on weighted encoding with image sparsity and nonlocal self-similarity priors regularization is proposed in this paper. The encoding weights and the priors imposed on the images are incorporated into a variational framework to treat more complex mixed noise distribution. Such noise is characterized by heavy tails caused by impulse noise which needs to be eliminated through proper weighting of encoding residual. The outliers caused by the impulse noise has a significant effect on the encoding weights. Hence a more accurate residual encoding error initialization plays the important role in overall denoising performance, especially at high impulse noise rates. In this paper, outliers free initialization image, and an easier to implement a parameter-free procedure for updating encoding weights have been proposed. Experimental results demonstrate the capability of the proposed strategy to recover images highly corrupted by mixed Gaussian plus impulse noise as compared with the state of art denoising algorithm. The achieved results motivate us to implement the proposed algorithm in practice.

A column is a structural member that bears an axial compressive load and is more likely to fail due to buckling than due to material strength. Some of these columns work at high temperature and this temperature effects the behavior of buckling. Then the designer must takes this factor into consideration. The present work involves the high-temperature buckling of 6061-T6 aluminum alloy rod(column) at different range of temperature (room temperature to 200°C). This work study the critical buckling load (Pcr) under the above temperature dynamically. The (Pcr) can be predicted by Euler theory. It has been observed that the Euler theory is not satisfy to applied under high temperature unless using temperature safety factor. The results show that elevated temperature weakens the structure and decreasing its mechanical and buckling properties. From the experimental results, empirical equations were derived to predict yield strength, ultimate tensile strength, modulus of elasticity, critical buckling load and temperature safety factor at high temperature.

The effect of three stir casting temperatures (ST) (900, 1000, and 1100 on magnetic and microstructure properties of AA5052 reinforced with 5wt% TiO2 nanoparticles has been investigated using the stir casting technique. It was found that the magnetic properties decrease with increasing stir casting temperature and the least magnetic saturation (Ms) and magnetic susceptibility (Xm) occurred for nanocomposite fabricated under stir casting temperature (1000 °C) also the maximum coercivity (Hc) and residual magnetization (Mr) occurred in this nanocomposite. The values of magnetic saturation (Ms), coercivity (Hc) and residual magnetization (Mr) obtained for nanocomposite under (1000 °C) are 2.714×10−6 (A/m), 4676.55530 (A/m) and 3.25032 ×10−8 (A/m), respectively. Scanning electron microscopy (SEM) is used to analyze the microstructure, and it is discovered that well-distributed nano particles lead to decrease grain size in the parent phase.

The INS system’s update rate is faster than that of the GNSS receiver. Additionally, GNSS receiver data may suffer from blocking for a few seconds for different reasons, affecting architecture integrations between GNSS and INS. This paper proposes a novel GNSS data prediction method using the k nearest neighbor (KNN) predictor algorithm to treat data synchronization between the INS sensors and GNSS receiver and overcome those GNSS receiver’s blocking, which may occur for a few seconds. The experimental work was conducted on a flying drone over a minor Hungarian (Mátyásföld, 47.4992 N, 19.1977 E) model airfield. The GNSS data are predicted by four different scenarios: the first is no blocking of data, and the other three have blocking periods of 1, 4, and 8 s, respectively. Ultra-tight architecture integration is used to perform the GNSS/INS integration to deal with the INS sensors’ inaccuracy and their divergence throughout the operation. The results show that using the GNSS/INS integration system yields better positioning data (in three axes (X, Y, and Z)) than using a stand-alone INS system or GNSS without a predictor.

This paper presents a high quality design of a 7th order Type-I Chebyshev low-pass filter (LPF) based on a stepped-impedance (SI) metamaterialized microstrip. The respective methodology involves embedding split ring resonators (SRRs) in addition to complementary split ring resonators (CSRRs) in filter design. The introduced metamaterialized filter manifestd better characteristics than in the conventional filter design and in some other availablefilter designs achieving lower insertion loss and appreciable size reduction. In this metamaterialized filter, miniaturization has been attained through implanting rectangular SRRs on top of the microstrip line besides etching squared CSRRs in its ground plane forming a defected ground structure (DGS). The design shows voltage standing wave ratios (VSWRs) of less than 1.05 in the pass-band interval yielding flattest pass-band with clear impedance matching. The shown group delay (GD) pattern is almost constant of around 0.5ns. Roger substrate material (RO3210) has been utilized with dielectric constant 10.2, substrate thickness 1.27mm, and thickness of microstrip conductor 0.035mm. Simulation outcomes have been obtained using the Ansoft High Frequency Structure Simulator (HFSS) package that is based on finite element method (FEM). The filter is applicable in most microwave (MW) and RF systems.

Radio-frequency identification (RFID) is an important wireless technology which utilizes radio frequencies (RFs) for exchanging data between two or more points (tags and readers), that represent an automatic identification (Auto-ID) system. This paper introduces an omnidirectional microstrip antenna operates at 2.45 GHz used for a radio-frequency identification (RFID) technology. The length of the proposed antenna is 36.5 mm and the width is 27 mm. The substrate material which has been used as a base of antenna is FR4 that has dielectric constant value of 4.3 and dielectric thickness value of 1.6 mm. Regarding the resonance frequency, return loss of the proposed antenna design is -34.8 dB. A promising directivity outcome of 2.8 dB has been achieved with omnidirectional radiation pattern as well as an acceptable efficiency of 66%. The proposed antenna design accomplishes a wideband frequency of 1.21 GHz in the frequency range of (2.14 3.35) GHz. The computer simulation technology (CST) microwave studio software has been used for implementing the proposed antenna design. The antenna design fabricatation and its characteristics have been measured using vector network analyzer (type MS4642A). The obtained results of the experimental design achieve a little bit differences as compared with the simulation results

This paper introduces several miniaturized symmetrical designs of high selectivity metamaterialized low-pass filters (LPFs) based on a stepped-impedance (SI) 3rd order Type-I Chebyshev LPF prototype. The pass-band interval of the prototype design manifests a nearly constant group delay (GD) ranging between 0.4–0.45 ns with lower level of ripples. It further exhibits voltage standing wave ratios (VSWRs) starting at value 1 and keeping on a reasonable level of impedance matching. To ensure for considerable metamaterialized LPFs designs, the methodology behind this work has resorted to exploit: split ring resonators (SRRs), complementary split ring resonators (CSRRs), besides open stubs (OSs). Qualities such as sharp cutoff, high selectivity, substantial size reduction, and low insertion loss, have all been achieved. The designs were applied on the Roger substrate material (RO3210) with dielectric constant of 10.2, substrate thickness of 1.27 mm, thickness of microstrip conductor of 0.035 mm, then simulated using the package Ansoft High Frequency Structure Simulator (HFSS). The applications field of these filters involves most microwave (MW) communication systems in diverse civil and military horizons.

Image compression solutions are a pivotal field that gain over a remarkable research interest and called upon to extend widely with respect to the increasing of its applications. The considerable challenge of this solution is related to the storage and bandwidth requirements. A highly compression rate with a high image resolution is considered to be the key factors for implementing a robust image compression technique. In this paper, the proposed method is deemed to be simple and effective due to using different levels of compression process which is starting from dividing the image into sub-images and using high level discrete wavelet transform (DWT). In addition, the Huffman code with non-uniform Quantizer has been used to minimize the compression data rate with high quality reconstructed image. The promising simulation results of the proposed method achieved the most two significant criteria which are denoted by high image quality and a high image compressed ratio. For instance, the proposed strategy simulation results of Lena image achieved PSNR equals to 42.4094 dB with a compression ratio (CR) equals to 47.5435. Moreover, the simulation results of Flower image accomplished PSNR equals to 42.8348 dB with a compression ratio equals to 55.3389 under the same simulation conditions.

This paper presents compact dual-band band-pass filters (BPFs) using microstrip transmission lines (TLs) loaded with metallic via holes (MVHs). The primary goals of the proposed design are to get size reduction and dual-band frequency response. An end-coupled line dual-band BPF with better size reduction has been obtained using MVHs as a single negative (SNG) metamaterial (MTM) component to achieve negative relative permittivity (ɛ r ). This component is adequate for designing dual-band BPFs to operate at 4.1 GHz and 6 GHz resonant frequencies. To the best knowledge of the authors of this work, “Dual-” band BPF based on MVH has not been experienced yet by any other work in the literature. The filters structure length is as small as one third of wavelength. The filters have been designed with a fractional bandwidth (δ) that exceeds 10% at the resonant frequencies. Numerical observations of the microstrip TL and end-coupled BPFs designs have all been discussed. Simulations were done by HFSS software and implemented on the substrate Roger RO3210 with dielectric constant of 10.8 and dielectric substrate height of 1.27 mm. These filters are convenient for most common microwave applications.

 Abstract—  In this paper, broadband microwave parallel-coupled band-pass filters for wireless microwave technology are presented. Two designs of filters with center frequency of 10.5GHz and 9.5GHz are proposed. A metallic split ring resonator (SRR) as a basic building block for planar filters with dual-band band-pass frequency response, which exhibits simultaneously negative permittivity and permeability as a metamaterial without resorting to additional metallic wires is numerically investigated. The effect of SRRs on these filters to get new two metamaterial dual-band microwave filters is also presented. The dimensions of the second filter are reduced compared to the first filter with better results. Numerical results for all designs are obtained, then the filters are simulated using computer aided design (CAD) in microwave applications (Ansoft HFSS) and implemented on the Roger RT/duroid 6010, Metamaterials (MTMs) are defined as artificial (fabricated by human), effectively homogeneous (p << λg) and exhibiting highly unusual properties (er, µ r < 0) not readily available in nature, where p is the average cell size and it is much smaller than the guided wavelength (λg) (4). Split-ring resonators (SRR) were one of the first particles proposed for metamaterial construction. Metallic metamaterials comprising double split-ring resonators (SRRs) are the main artificial structures to realize magnetic responses at an electromagnetic spectrum above gigahertz frequencies (5)-(8). The realization of backward wave propagation using split ring resonator (SRR) and thin wire (TW) and several other electrically small resonators was considered by Pendry (5), ( 9). The split ring resonator shown in Fig. 2 is used to obtain a negative value of effective permeability over a desired frequency range.

A design of an ultra-wideband (UWB) bandpass filter (BPF) is presented depending on the composite right/left handed-transmission line (CRLH-TL) basis. The interdigital (ID) coupled lines and complementary split ring resonators (CSRRs) are the tools used to realize an UWB microwave filter with an appreciable size reduction and better performance. The bandwidth resulted from this filter is 5.6 GHz operating at 3.2 GHz center frequency. The interdigital elements are connected to the input and output ports through square closed rings in the upper side of the microstrip line, whereas the CSRRs are etched in the ground of the microstrip line. All components contribute together to get metamaterial (MTM) media containing negative permittivity and negative permeability. The simulated results show that the filter has a flat insertion loss of less than 1 dB with an acceptable return loss performance in the frequency range (0.4–6) GHz. The achieved quality factor is equal to 0.57 and the fractional bandwidth is over 100 %.

This work proposes an end-coupled half wavelength resonator dual bandpass filter (BPF). The filter is designed to have a 10.9% fractional bandwidth (FBW) at center frequency of 5.5GHz. Dual-band BPF with more drastic size reduction can be obtained by using metallic vias act as shunt-connected inductors to get negative permittivity (-e). The process of etching rectangular split ring resonators (SRRs) instead of open-end microstrip transmission lines (TLs) for planar BPF to provide negative permeability (-μ) is presented. The primary goals of these ideas are to get reduction in size, dual- and tri- bands frequency responses. These metamaterial transmission lines are suitable for microwave filter applications where miniaturization, dual- and tri-narrow passbands are achieved. Numerical results for the end-coupled microwave BPFs design are obtained and filters are simulated using software package HFSS. All presented designs are implemented on the Roger RO3210 substrate material that has; dielectric constant e r=10.8, and substrate height h=1.27 mm.

This paper presents a compact stopband filters and bandpass filters using microstrip transmission lines coupled with two parallel sides of square split ring resonators (SRRs) and metallic vias holes. SRRs etched on the upper plane of microstrip line to provide negative value of effective permeability (μ < 0) to the medium in a narrow band above their resonance frequency. Narrow bandpass filter with more drastic size reduction can be obtained by using metallic via holes to get negative effective permittivity (e < 0) with negative effective permeability (μ < 0) which is generated by using SRRs. Backward wave propagation is achieved as a LHM when SRRs and via holes are applied together. These metamaterial components (SRRs and metallic via holes) are useful for compact narrow stopband and narrow bandpass filters applications at 3GHz resonance frequency. The process of adding many numbers of SRRs and taking many widths of strip conductor (W) with gap variations between resonators and strip line are studied and simulated. The length (l) of the structures can be as small as 0.3 times the signal wavelength at resonance frequency.

In this work, the tuning forks (TFs) shape and complementary split ring resonators (CSRRs) are the tools used to present new UWB microwave filters. Two tuning forks are printed on the upper side of the microstrip line covering the host transmission lines. The filter bandwidth containing tuning forks is ultra-wide and equal to 11.8GHz operating at 6.1GHz center frequency. A novel method to upgrade the matching between the host transmission lines and the CSRRs is proposed as well. The bandwidths of the developed filters containing tuning forks with the presence of different CSRRs at different designs are 10, 6.8, 5.5 and 4.7GHz at 5.4, 3.6, 3 and 2.55GHz center frequency, respectively. The negative permittivity metamaterial is made of CSRRs which are etched in the lower side of the microstrip line. These metamaterial filters combine negative characteristics of permeability and permittivity which are created by using TF and CSRRs components respectively to create an UWB response with better performance and size reduction. The simulation results showed that the filters have composite right/left handed (CRLH) behavior with insertion losses less than 1dB and suitable average rejections.

To attenuate the channel fading effects, a spectrum sensing policy for coordinating a cooperative sensing is proposed by adding a Hopping Sequence (HS) module to the detectors based on a fuzzy logic system (FLS). A significant effect on the spectrum efficiency is the ability of a secondary user (SU) to utilize a frequency slot for transmission in an idle channel. Hence, the SU needs to sense the related spectrum in order to classify a licensed frequency band as occupied or vacant. To implement the HS module, two hopping methods are proposed- Random Hopping (RA-H) and Sequential Hopping (SE-H). An enhancement in detection probability over conventional cooperative sensing has been achieved.