A Review on Different Optimization Techniques for Selecting Optimal Parameters in Microstrip Bandpass Filter Design
Hussain Bohra1*, Amrit Ghosh2
1*Department of Electronics and Communication Engineering, School of Engineering, Sir Padampat Singhania University, Udaipur, India
2Department of Electronics and Communication Engineering, School of Engineering Sir Padampat Singhania University, Udaipur, India
Abstract
There has been growing attention recently among organic process improvement algorithms such as Ant Colony improvement (ACO), biogeography primarily based Optimization (BBO), Differential Evolution (DE), Population-Based progressive Learning (PBIL) and Stud Genetic Algorithm (SGA) to some new techniques, here, taking into consideration completely different newly developed biological process improvement algorithms, the design of a microwave microstrip passband filter is mentioned in order to match their performance on a composite index EM improvement problem. Certain techniques (DE, BBO, SGA) are effectively cope up with this kind of complicated EM problem as shown by the results.
Keywords: Ant Colony improvement, Biogeography based Optimization (BBO), Differential Evolution, Population-Based progressive Learning, Stud Genetic Algorithm (SGA).
_______________________________________________________________________
1. Introduction
Bandpass filters from microstrip are in constant demand for low-profile and lightweight systems. In order to meet stringent requirements in trendy telecommunications, there is a need for transfer functions that derive from generic Chebyshev features. Particularly, characteristics with increased flatness of cluster delay, steep passband slopes, and transmission zeroes closely placed to the band edges are usually preferred.
In [1], an approach is explored to consider, plan and produce bandpass filters for the WiMAX application at 3.2 GHz frequency with parallel-coupled microstrips that produced filters for 5.75 GHz wireless local area network, along with the use of composite resonators and ventured impedance resonators for filter recognition.
In [2] the goal was to create a scaled-down, well-performing limited band LTCC filter.
Specific project tests of microstrip filters with taped feed lines along these lines have been investigated. A method for developing ultra-wideband (UWB) microstrip bandpass streams, broad stopband, and down to earth measurements is shown in [3]. According to the proposed methodology, a ventured impedance parallel-coupled microstrip structure is correlated with three subsections with different lengths and coupling variables.
In [5] a Wi-max portable microstrip poses some real issues today. In favour of such a bandpass channel system that employs short-circuited stubs. A whole new transmitter and receiver like Wi-Max is required by the authors The Wi-Max bandpass frequency is distributed on 0.8 mm thick dielectric substratum FR4 and the bandwidth covers an area of 38.64mm2. Another approach is proposed in [6] for developing wideband BPF with harmonic suppression. For explain the concept of the design, both the T-shape resonator operating principle and the analysis of the proposed stub for the additional change zero are shown. In order to approve the proposed project concept, one instance balun BPF is then organized and simulated.
To eliminate the related harmonic, a new fractal microstrip clasp line BPF is proposed in [7].
With this framework, a prototype channel with an average frequency of 1 GHz has been developed, created and calculated [8] surveys the development steps of a microstrip Pass Filter
band. The basic model discussed in detail in the article is called the Parallel Coupled Filter. In this study a filter configuration case is provided over which a channel is configured using certain tools.
[9] suggested an overview of substantial filter design reviews for band-pass filters and a dialog on various designs using different methods or techniques used to achieve wide-band applications and controllable capabilities. The past work will be examined and ultimately broken down in terms of losses, bandwidth, data transfer efficiency, selectivity and tuning in order to provide a proposed new microwave channel project with band-pass and tunable score reaction in the UWB application for future research work. [4] provides an overview of enormous knowledge, its significance in life and some progress in dealing with vast data. A progress strategy based on hybrid genetic algorithm (GA) strategies is shown in [10] to design smaller dual bandpass channels with microstrip lines. A representation scheme is proposed to connect as a ton of data structures with a discretionary microstrip circuit. Each measuring structure in the package depicts a large two-part project with the device and electrical parameters of the combination. The generic GAs-based improvement algorithm is then connected to all scanning for the right topology of the circuit and related electrical parameters with double band mark A further lower UWB than hybrid BPF was suggested in [11] based on the CRLH-TL metamaterial concept. Only one CRLH-TL device is chosen, and the two sets of open stubs inside and outside are incorporated to frame the desired bandpass region. Once three dimensional EM (electromagnetic) field has been re-enacted and developed, the estimation approves the scheme to show a fantastic frequency response display with a 3.2 to 4.8 GHz band, an additional insertion loss of (< 1 dB), and a return loss of (< 15 dB). An improved three Wilkinson control divider hybrid is shown in [12] centered on a low-pass channel The one-minute (MoM) molecular swarm improvement process and strategy (PSO) has been used to increase the transferability of knowledge to cover the two adequately 8 GHz ultra-wideband varieties equivalent to 120 percent fragmentary transmission efficiency and to ignore higher frequencies. The parts of the dividing squares and Wilkinson confining resistors are used entirely as improvement variables. MOM renderings test wellness capacity and use the MoM to evaluate the answer of the Wilkinson control divider suggested. In order to plan a successful ultra-wide channel (UWB), it suggests enhanced particle swarm optimization (PSO) [13]. The channel consists of a resonator with a one-cell composite transmission line (CRLH-TL) on the right and left hand side, a working impedance (SI) and two spur lines. The one-cell CRLH-TL resonator has minimal volume;
however, it performs large passband sifting. Outside the UWB band as well as the distant neighbourhood (WLAN) band (5.15-5.825 GHz), one SI and two spur lines are used to reject audio.
[14] makes further use of the transformative streamlining algorithm to design a minimum surface frequency (FSS) specific bandpass profile. A particle swarm optimization algorithm is interfaced is interfaced to model the time area solver for a business and improve a 10 GHz FSS second demand bandpass with partial data transmission of 20 percent. The standard solutions to the ultra-wideband (UWB) remote microstrip bandpass channel communication of the ship have some problems. In [15] based on the distributed algorithm, an optimal design method for the microstrip bandpass channel is suggested in UWB distant ship communication. The low pass channel is combined with a high pass channel which is used in UWB distant vessel correspondence to complete the microstrip bandpass channel scheme [16].
It explores the impact on reduced execution of microstrip channels of adaptive genetic algorithms (AGAs) and deficient ground structures (DGSs). The suggested model accomplishes an ultra-wide stopband with elevated constriction in inspection with periodic channels within a small surface region, just like 45 percent more modest length. Using AGA code in-home enhances the parameters of the channel The hybrid and transformation probabilities were adaptively modified by the employee health calculation in the proposed AGA algorithm. [17]
ASM is implemented and a 6th device dual-layer microstrip interdigital channel is built using ASM with 20.4 GHz indoor frequency and 1.6 GHz data transmission. The channel hit settings lists after seven cycles, which greatly reduces the amount of recreation in the excellent design, saving time.
For this purpose alone, microstrip bandpass channels were suggested in [19] using piece-type coupling frame centered on multi-target streamline. The coupling arrangement of the component form enables improved quality in the bandpass channel program. It is possible to execute channels with seductive execution of the upper stopband and through occupation zone. As a result, the segment style coupling design strategy can be achieved by multi-target progress with a few structure targets reflecting bandpass channels. A cooperative split-path technique is proposed in [20] to roughly anticipate the complete frequency and topology of bandpass channels that are typically below the heuristic structure level. Bended transmission lines are often needed to physically reduce channel topologies; however, complete or focused frequency prediction for bandpass channel plan can trigger errors and flow effects. Past bend corrections recommendations are impressively precise, but ongoing design requirements need even higher precision. A Bandpass end-coupled line (BPF) channel is suggested and scheduled by putting faulty ground structure (DGS) in the ground plane at [21]. DGS is used for reducing the size of the microwave channel and enhancing its control of the prevalent link between the resonators.
The recommended DGS hand weight is used with a measurement of 44 mm/18 mm to change the bandpass channel to 2.4 GHz. By adjusting the DGS unit cell's tallness, length, and width size, a broad tuning range of 0.64 GHz is achieved.[22] provides a student's point of view and a complete study of defective ground structure (DGS) microstrip channels. DGS concept is influenced by photonic / electromagnetic bandgap (EBG / PBG) constructions and metamaterials used in microwave components to achieve a variety of highlights in performance enhancement.
Compared to complicated EBGs / PBGs, it is far less difficult to demonstrate DGS and metamaterials as an L-C proportionate lumped circuit DGS was used by the microstrip channels in this analysis to provide a point-by-point history.
A non-uniform bandpass channel with defective ground structure is implemented in [23]. The scheduled channel width is achieved using an improved U-shaped and non-uniform process. In contrast, to gain multiband, the use of a defective ground structure (DGS) is used. High- frequency structure simulator (HFSS) and computer simulation technology (CST) programming bundles are used to illustrate the suggested scheme.
[31] proposes a novel ultra-wide bandpass (UWB) channel (BPF) using double-scored triangular defective ground structures (DGS). Two balanced free weight moulded interdigital capacitors were designed to maximize the appearance of the BPF. Three sets of reduced abandoned floor structures were considered and implemented by dispensing their transmitting zeros to the out-of-band signal to stifle the incorrect passband. A large UWB BPF is obtained by consolidating these two buildings.
The new design of the bandpass channel was shown in [43] using the simple topology of the square loop resonator of the stepped impedance. A 10.8 substratum with constant insulation, 1.27 mm thickness and 0.0023 loss tangent was used to test and improve the proposed bandpass channel at a frequency of 5.8 GHz. The simulation tests are analyzed using the Sonnet test system, commonly accepted in research and use on microwaves. The yield frequency findings showed that the suggested channel has excellent frequency responses given separated second symphonic frequency. Furthermore, this channel has a small surface area, and visible narrow band response involves speaking to late distant correspondence systems part measurement status.
[44] proposes asymmetric step-impedance bandpass resonator channels (ASIRs) to stifle a large stop band, reduce size and simplify output. Using hybrid-wavelength irregular advance impedance resonators, the channels are balanced at the operating frequency about 2.0 GHz.
Using open-circle resonators with interdigital capacitors in[45], the concept of current odd-and - even-mode characteristics is used to endorse the suggested channel structure. The indoor level is effectively controlled by the interdigital condensers. Based on parallel and aggressive parallel paired lines, the appropriate coupling topologies will allow an inverse phase difference between sensitive returns. Specific uneven size characteristics between decent ports can also be obtained along these rows. Based on a parallel-coupled line structure and a cross-formed resonator with open stub in [46], a wideband bandpass channel (BPF) with reconfigurable data transmission (BW) is proposed. The p-I-n diodes are used as tuning components that can be reconfigured to change three BW states... The uniform channel model shows a flat BW tuning range of 1.22 GHz, whereas the partial BW is clustered at 5.7 GHz from 34.8% to 56.5%.
In the light of a new microstrip-ended cross-formed resonator (TCSR), the double-band bandpass channels (DB-BPFs) with fixed and reconfigurable data transfer capacities are proposed in [47], provided the three shafts and four zeros of the basic TCSR, many also parallel- coupled lines and open-ended stub lines can be used to provide additional four posts and three zeros.
A planar DB-BPF with different transmission shafts and zeros can be found in this way. In order to achieve the reconfigurable transfer speeds, a condenser is embedded in the lower stub of the essential TCSR.
[48] provides instructions on a basic approach to superconductor (HTS) management at high temperatures. The concepts are implemented to provide a general view of the problem, while the references are selected to enable a deeper understanding through all accounts where appropriate for the per user. In [49], a geometrically balanced fractal structure is introduced to provide an alternative way of coping with scaling down scheme microstrip bandpass filters (BPF). The geometric age operation is described in detail and another fractal resonator called the Greek-cross fractal resonator (GCFR) is given by rubbing the suggested fractal design outside the normal double-mode wound panel resonator.
Four microstrip BPFs were presented and recreated on the basis of the original four GCFR accent. The recreational results show that the focal frequency of the BPF is moving bit by bit towards the low frequency with the expansion of the pressure quantity, which indicates the normal miniaturization of the proposed fractal resonator. A new bandpass channel with a 2nd consonant dismissal potential based on a minimized ring resonator is proposed in [50]. The presented bandpass channels use open stubs in stepped topology and a stepped impedance ring resonator at bolstering rows. Open stubs structures are used for a lower dismissal extent in the 2nd consonant frequency band. The ring resonator array computed through analysing and recognizing the own quality situation of the ring resonator. Right off the bat, the second demand bend from Sierpinski is employed to attain compactness of approximately 66% and 71% in comparison with the normal microstrip ring bandpass channel inward and outer regions respectively. Sierpinski bend is chosen for symmetrical bolstering lines and open stub consolidation without any extra space due to its balance and reasonableness. The proposed first re-enacted fragmentary transfer frequency of Sierpinski structure −15dB is 5.6 percent at 1.505 GHz with a dismissal of −0.16 dB, equal to the peak dismissal rate. Transmission zeros were obtained at 2.25 GHz and 3.78 GHz. In addition, extra transmission zero can be obtained at 3.84 GHz frequency component by incorporating open stubs in stepped impedance form attached to the resonator ports. The proposed 2.9 GHz structure, the second harmonic band, achieves −6.7 dB dismissal for the periodic band instead of−1.7 dB. The estimated recreated partial transfer velocity of −15 dB is 3% at 1.42 GHz. Design is accomplished through the effortlessness of transmission zero embedding, regulating zero dismissal appreciation, fusing stubs and symmetric nourishing lines in a comparable resonator area and responsive potential of the suggested framework.
A particular quantity of state-of - the-art EBGS plans is given in [52] and explained with some detailed parametric investigations. In the sense of modern uniform ring, square and annular models, this epistle honors planar-EBG structures. By a comparable token, the optimum Filling Factor was examined through breaking down the bandpass channel's normal frequency response from three fundamental viewpoints, such as beginning the stopband investigation, passing the band test, and informing the stopband inquiry.
In [53] the geometric room is used by a narrower double-mode microstrip bandpass array. The geometric opening approved is based on the first step of the fractal bend of the Cantor square.
Compared to microstrip channels using single-mode resonators and standard dual-mode square resonators, this channel has the advantages of having frequency responses lower and higher. The stream was measured and tested by a Microwave Office EM test scheme equipped with a complete 2 GHz frequency using a substratum of r=10.8 and h=1.27 mm thickness. The yield reacted effect of the proposed channel shows the 22 dB return loss, 0.1678 dB inclusion loss, and data transfer capacity of 12 MHz from the passband locale.
Only because a parallel-coupled tuned microstrip channel is shown in [54] for millimeter wave frequency applications based on nematic fluid precious stones (LC) substratum. It is found
that the proposed channel of 3.3 GHz has 3-shafts, a transmitting capacity of approximately 10 percent at 3.3 GHz and a dynamic range of 2 GHz over tilt voltages in the range of 0 to 10 Volts.
The channel's theoretical and testing responses are well known. The additional channel loss is about 4.5 dB, but this is due to changes made to measure the channel by the microstrip line to CPW by a test station.
In [55] the framework and exploratory depiction shows a tunable microstrip bandpass channel based on fluid precious stone growth. To boost the execution of the device, a reshaped double- mode microstrip channel structure has been used. In general, the aim is to increase the passband return loss of the channel by increasing the channel transfer rate. Simulations affirm the change in the use of this new framework, at any level achieving a 1.5 dB increase in the loss of passband return.
Simulation and testing have been used in [56] to present and test a design of planar tunable bandpass filter. Nevertheless, the suggested solution can be easily extended to other frequency bands from L to above W using substituted hexaferrite substrates for textured, spinel, and garnet.
In addition to the bandpass filter response shown here, other parameters like cut off frequencies, bandwidth, in-out band frequencies, selectivity factor, skirt rate etc. can also be considered. The useful distinction between imitated and projected channel efficiency was shown, with the insertion loss measured at a passband centre frequency of 1.3 dB in comparison to 0.9 dB as observed in simulation. The channel reaction tuning was demonstrated by applying low attractive fields from 50 to 200 Oe to frequency varieties from 8.3 to 9 GHz in passband core. Despite the benefits of lower loss, economical and ease due to inalienably radiation-tolerant properties, the proposed channel configuration has the potential for fast and low-influence tuning, high- influence care, and space applications suitability.
[57] describes how the 2.45 GHz interdigital microwave bandpass channel can be organized.
In this way, this research revolves around the parallel-coupled line bandpass channel project, two arrangements of the 2.45 GHz interdigital bandpass channel on single-layer structures, think about among these networks, suggested one appropriate for users. The mainly coupled line channel was intended for single-layer structure at that point and even for interdigital transfer channel. In order to design these channels and to think about the outcomes of the re-enactment, extraordinarily successful, ground-breaking system programming Advanced Design System ® and Sonnet EM reactions were used with recurrence transmission coefficient Forward, forward reflection coefficient was spoken to and similar analyses was carried out between planned channels. Outstandingly similar to the optimal reaction are replicated results. The results showed that at working frequency , each channel works admirably. Topsy-turvy channels at target recurrence have incredible return loss, incredibly sharp off-factor movements. The re-enacted outcomes, however, were similar to the ideal description but not in fact synchronized with the ideal determination. Brand regulations are a basic reason behind this situation. This could be due to the failure of the PC to manage large records of memory re-enactment. Some consumer confines are available to finish the reproduction with exact results in a desirable time period.
Despite the fact that in this way the standardized channel did not flawlessly reach the specific, there is scope for further progress. [58] consists of a 60 GHz wideband bandpass channel powered from a strong polymer substratum of PerMX. A typical parallel-coupled half- wavelength resonator channel is chosen as a latent frame added. A slight 5 μm gap between 750- μm-long resonators is expertly made due to the a-Si bolster substratum. Surface change is used to separate the flexible polymer substratum from the Si substratum after assembly of the tube. A wideband channel is achieved by reducing the close holes between adjacent resonators. The standardized channels are installed with a spread and distributed in two distinct types. The spread-free channel shows an additional 4 dB loss at 63.5 GHz concentrate recurrence and an arrival loss of more than 10 dB with two CPW plates, while the spread channel shows an inclusion loss of 3.8 dB at 59 GHz and an arrival loss of more than 13 dB. In any case, the exposed channel has a 24 per cent 3-dB data transmission at 63.5 GHz, while the protected channel displays 28 percent at frequency of 59 GHz. [59] Using a triple-mode dielectric resonator (DR) installed in a built-in waveguide (SIW) substratum, new bandpass channels are provided. Ansoft HFSS first calculated and repeated and emptied the complete recurrence-a factor of DR. It was then based on DR projections. Improving, reproducing and estimating a
solitary triple-mode SIW fitted with a tuning module DR stream. Inaccurate suppression with root and burden couplings was considered just as affecting formation. A six-mode channel using two DRs was also proposed and tried. These channels demonstrate strong understanding between recreation and estimation impacts and have the advantages of low addition loss, smaller size, and precise mixing with other planar circuits. Advancing minimal effort, low inclusion loss, and scaling down channels for remote correspondence frameworks is referring to the proposed idea [60] proposes an integrated power divider based on a microwave-based variable bandpass channel based on nematic fluid liquid crystals (LCs). The proposed power divider uses a precious stone (LC) fluid as a dielectric material. By altering the dielectric anisotropy, it can allow a stage change while biasing the high anisotropic nematic fluid precious stone. It is primarily used in the microwave wavelengths. In comparison to standard channel synchronized power dividers, it has many points of interest, such as low loss, multifunction fuse, stable parameter, scaling down, low cost of planning, low voltage of operation, rapid stage shift, and advantageous yield. It has also shown a tremendous opportunity for use. Meanwhile, the continuously factor microwave bandpass channel coordinated power divider is given another advancement technique to address existing issues such as the limited specialized tuning range, low linearity, significant expenditure, and sophisticated control rationale.
2. Optimisation Techniques Applied in Designing the Microstrip Bandpass Filter
This section will review the various techniques applied for optimising the design of microstrip bandpass filter.
2.1 Application of Optimisation Algorithms 2.1.1 Ant Colony Optimization
ACO is a generally novel measure of progress that has been applied as of late introduced to the improvement of the EM problem. This method has a situation with the development equations family based on the population and is worked up by the searching behaviour of ants. The key ant’s innovations are stochastic, but when the origin of nourishment is identified, the shortest way between nourishment and home is separated by ants-discharged pheromones to direct the other individuals of the community. A famous example of using this figure in the supposed TSP (Traveling Salesman Problem), in which, irrespective of various urban networks, the most direct trip to each city should be scheduled once and for all. An artificial ant colony is considered via ACO, and each provides a response to the issue. A pheromone quality is linked to each portion of the arrangement so that each underground ant has a manual for a remarkable arrangement in the corresponding process.
2.1.2 Biogeography-Based Optimization
BBO is a fundamental measure that relies on the technology that has been modified in biogeography. Biogeography is the research into the land distribution of familiar living creatures [3]. BBO shares a few models with other formative headway methodologies, so it's relevant to numerous issues that could also be known with GA and PSO, especially high-dimensional issues with various optima networks. Regardless, BBO also has a few features that are different among science-based update techniques. So come clean, BBO's potential game plans are assigned islands or living spaces, and their chairmen rely on the concept of movement to share information for the problem between the action courses.
In general, BBO is adding four new parameters:
a) Suitability Index Variable (SIV) refers to a dynamic reflecting tenability in an island, e.g. in an answer.
b) Habitat Suitability Index (HSI) refers to the honesty of the system, in contrast to GA's definition of wellness ranking.
c) Emigration Rate shows how probably a response with different arrangements is to share its highlights.
d) Immigration Rate reveals that an answer is to remember highlights from different arrangements.
Superior ecosystems have high rates of resettlement and low rates of travel, while poor biological systems have low rates of relocation and high rates of migration. By and wide, the greatest possible recurrence of motion occurs when there are no species in the natural environment. As HSI expands, the amount of species grows, the living space ends up being filled slowly, and that's just the starting species that can move away from the island to accommodate alternative possible living spaces, extending the rate of resettlement in this way.
2.1.3 Differential Evolution
It could be a new heuristic method for getting optimum continuous house functions that are nonlinear and on-differentiable. His EM and EMC drawback software were recently analyzed. A population in DE is made up of vectors initialized from a homogeneous distribution in every way. Each vector is a response. The underlying population shifts in each era with the work of three administrators: transition, hybridity, and commitment, as in GA. Inside the reading, there are various DE varieties or techniques, depending on the type of these managers. DE requires a few board variables, is robust, simple to use, and suits parallel figure.
2.1.4 Population-Based Incremental Learning
PBIL may be an algorithmic organic system rule variance wherever a full population genotype (probability vector) occurs instead of individual members. In PBIL, genes are delineated as varying real values, indicating the probability of occurring some particular factor in them. Once the chance function produces a brand new population, each member's fitness is measured and graded. The most suitable entity is then modified to support the population genotype (probability vector). Mutation is usually used to promote diversity and earlier loss of data.
2.1.5 Stud Genetic Algorithm
SGA is a slightly dark variation of Khatib and Fleming's remarkable Genetic Algorithm developed years earlier. The fundamental idea behind SGA is to use the best person in the community to organize with all others the new posterity. Regardless, no stochastic assurance is used, after an abnormal population is mounted, the most appropriate individual (the Stud) is selected for mating. Hybrid is performed between the Stud and the rest of the pieces.
2.2 Use of Defected Ground Structure
[31] offers a highly entertaining ultra-wide bandpass (UWB) channel (BPF) with twin- contact groups cross-sectionally over triangular defective ground structures (DGS). In the state of free weight, two even interdigital condensers are intended to support BPF efficiency. A super-minimal ultra-wideband (UWB) microstrip band-pass (BPF) channel with delicate properties and extensive stopband [32] is secure. The super-minimization near the expansive stopband of the normal channel is accomplished by collecting activity- adjusted low-pass filter (LPF)-based multimode resonator-based UWB BPF and defective ground structure (DGS). In[34] it is proposed and anecdotal a UWB bandpass channel with twin-contact groups using a T-molded resonator and L-formed microstrip structure.
The planned channel has twin adjustable scored groups used to change the structure of the L-molded microstrip deformity and the parameters of the T-formed resonator. A novel high microstrip band-pass loop, which is built up by embedding a ventured impedance single-wavelength ring resonator (SORR) into a ventured impedance semi-wavelength (SHR), is provided in [36] with the assistance of a four-mode ring resonator. Another
ultra-wide microstrip (UWB) bandpass (BPF) channel with two sharp scores is arranged in [37] using an E-formed resonator. The circuit topology and its comparative electrical parameters of the underlying microstrip UWB BPF are achieved by a hereditary measurement (GA) update. In [41], a simple, reduced bandpass channel template is implemented. The channel structured depends on the resonator stacked in the stub (SLR).
This consists of two wavelength-packed stub [*fr1] open ring resonators. The look is performed in two stages to get the ideal double band response. The critical band is generated by two-wave open ring resonators, while the opposite band is provided by stacking a stub to the wave open ring resonators. A simple, compact filter template for bandpass is implemented in [42]. The designed filter is based on the stub loaded by the resonator (SLR). This consists of two wavelength-packed stub [*fr1] open ring resonators.
To achieve the desired dual-band answer, the analysis is performed in two stages. This kind of structure is known to be defective ground structure (DGS). DGS's many benefits are that it brings influence on the slow wave. This effect produced equal and elements attributable to the DGS. The cables with DGS offers the next effective ohmic resistance and additionally introduces high slow wave effect, that provides rejection band in some frequency vary. Compared to the standard microstrip, the microstrip line with DGS has a huge electrical range for the same physical size. Thus, DGS helps lower the resonance frequency, thus increasing the corresponding degree antenna dimensions. The proposed manually molded DGS in [21] is employed for tuning of bandpass channel to 2.4 GHz with measurement of 44 mm × 18 mm. This paper discusses DGS’s creation and evolution. Conferred the basic ideas, operating principles, and corresponding versions of various DGS area unit shapes. In context to miniaturized microstrip radiating elements, DGS has been used to improve the information calculation, antenna’s gain and to alleviate the harmonics of the upper mode, the mutual coupling between the adjacent component and the cross-polarization of the microstrip antenna. Fashionable communication requires the availability of cost-effective, portable and mobile devices to be run at less signal intensity and good data rate. Researchers are working towards the RF front ends case and development to suit the new needs. Different novel approaches are rumored to improve microwave component efficiency. John and Yablonovitch intended PBG to provide a certain frequency PBG rejection band. A band of rejection provides a periodic structure on the bottom plane. Nevertheless, it is extremely difficult to model the PBG structure for microwave and millimeter-wave components.
Defected Ground Structure (DGS) was specifically designed to solve these problems and used the term "DGS" to describe a defect created by a dumbbell. The DGS is known to be a simpler variety of EBG structure that has a band-stop property in addition. DGS opens a door to a wide variety of applications for microwave researchers. Different novel DGSs are designed and heap of applications are thoroughly explored in microwave circuits. Due to its simplicity and low value, DGS has become another EBG for contemporary applications. Dumbbell shaped DGS was a filter from the start, and various shapes were later rumored to appreciate entirely a long range of applications viz. couplers, filters, power dividers and amplifiers. The DGS is developed into an MPA. Antennas for the test of deferential DGS were investigated. For active and passive applications, DGS is commonly used today. DGS structure has unique characteristics and has a great impact on the system’s output in line with its pure math and scale. To improve their efficiency, DGS are incorporated in various applications e.g. amplifiers, microstrip filters and antennas, waveguides etc. DGS is used for the miniaturization of component measurements, the enhancement of functional information measurement and gain, the suppression of harmonics in the upper order and unnecessary cross-polarization, and the additional processing of knotted bands to avoid interference with any band. Many DGS applications out there in the additional unit listed in the literature zone. There are reports of various DGS shapes constructing standard circuits. In model bandpass and band-stop flat filters, completely different DGS shapes are explored. To make a filter answer, a DGS in dumbbell topology was initially engraved in the ground metallic plane under a microstrip row. This disturbs the magnetic fields of attraction around the defect and affects electrical
fields that contribute to the effect of the electrical anomaly, whereas the surface currents in vicinity of etched area results in relative inductive effects. As a consequence, DGS's resonant characteristics, resulting in filter power. In [42], a simple, compact bandpass filter model is implemented. The expected filter for stub loaded resonator (SLR) is predicted. This consists of two λ/2 open ring resonators filled with stub. In order to attain dual band characteristics, the analysis is performed in 2 steps. In [43], via easy structure of stepped ohmic resistance square loop resonator, a brand new BPF model was given.
The proposed bandpass filter was modeled using an image using a 10.8 dielectric constant substratum, 1.27 mm thickness and 5.8GHz center frequency loss tangent of 0.0023. The simulation tests were analyzed using a widely implemented Sonnet system in the study and application of microwaves.
2.3 Optimisation Based on the Resonator Design
A method for structuring a composite microstrip bandpass channel (BPF) with a fractional bandwidth of more than 100% is created. The BPF is appropriate for wireless communications with ultra-wideband (UWB). The model also uses the integration into each other of separately designed high-pass structures, low-pass channels (LPF), followed by an optimization for in-band performance tuning. The stepped-impedance LPF is used to attenuate the upper stop-band and short-circuited quarter-wave stubs are used to measure the lower stop-band. [24] introduces four unique design models with and without DGS for low-pass and band-pass filters. For all systems, program strategy, enhancement subtleties, development subtleties, and tentatively gathered knowledge are added. Rohde and Schwarz ZVA40 Vector Network Analyzer are used to evaluate the models. [28] introduces a dual- band channel design using a novel ring resonator and H-deserted surface. The bandpass filter is designed to be strengthened and recognized using mixed coupled microstrip double ring resonators and two electrically coupled DGS resonators that are scratched in the structure base. Using this new ring structure prompts, two confined passbands create a different bandpass filter. The results of the estimate show that there are two passbands on the enhanced stream, the main band from 1.6 GHz to 2 GHz and the other from 3.6 GHz to 5.5 GHz. The proposed structure consists of a territory of λg = 0.044 m (0.45 λg x 0.35 λg). The findings re-established and tested indicate great understanding and support the approach proposed.
2.4 Optimisation Based on the Dielectric Material
For broadband dielectric lens antennas, an optimization -based matching layer design technique is implemented. The lens structure and related layers are modeled as a cascaded transmission line and the maximum amount of power transfer from feed to air is accomplished by significantly reducing the dielectric -air interface internal reflections. For down to earth applications the material with the determined relative permittivity ought to be financially accessible. Because of proposed strategy, business materials can be picked as ML materials in the advancement method. More significantly, when the MLs planned by the proposed strategy will be helpful for ultrawide band applications also. It ought to be likewise accentuated that the radiation qualities of the dielectric focal point reception apparatus, for example, directivity, SLL and front-to-back proportion are improved with the streamlined MLs in both restricted and wide recurrence groups.
3. Comparative Analysis
Finally, a comparative table will be developed based on the techniques discussed above .
Table 1. Comparative Analysis
Ref. No. Technique used Advantages Disadvantages Applications
1
Bandpass filter for the WiMAX application at the
frequency 3.2 GHz with parallel-coupled
microstrips as opposed to.
The bandpass features are applicable for a
wide range of spectrum.
There exist losses which need to be
ignored while measuring simulations from
Sonnet.
It can be used to design good
filters with Sonnet once
losses are eliminated.
2
Bandpass Filters With Normally Fed Microstrip
Resonators Loaded by High-
Permittivity Dielectric.
It provides sharp slopes and transmission
zeroes at a feasible rate.
No performance analysis was carried out for
optimal impedance
match.
The design needs to be updated for any
new LTCC filter development.
3
UWB BPF With Wide Stopband
Using Parallel-Coupled Microstrip Lines.
Wider stopband upto more than 27 GHz and insertion loss of
upto 1 dB recorded.
There is loose coupling in the side subsections.
Any UWB application can
use this technique.
5
BPF using Short Circuited Stubs.
It is easily implemented with LPF and
BPF being implementing
side by side.
These LPF and BPF needed to be
implemented together to save
space.
Mobile Wi- Max application.
6
Wideband Bandpass Filter
with Harmonic Suppression.
It provides nice sensitivity and
excellent harmonic suppression.
The filter is dominant in
nature.
It can be used in current advanced wideband wireless communication
systems.
10
A technique for optimization in conjunction with hybrid-coded GA
approach.
A miniature filter design obtained
with efficient frequency
response.
The computing time needs to be
reduced more.
It can be used for designing AI related
filters.
11
Wideband compact Bandpass filter implemented by
GA algorithm and interdigital
coupling structures.
Return loss (< 15 dB) and insertion
loss (< 1 dB) recorded.
Although zeroth- order resonance (ZOR) situation is validated yet it
is not accurate.
It can be used to develop
filters in wireless systems through Generic algorithms.
13
Miniature size UWB filter designed by employing
It blocks unwanted interferences.
The overall system faces performance degradation as
Automated and proficient
design of complex filters
enhanced version of particle swarm
optimization algorithms.
the ripples do not cause any interruption during insertion
loss.
and radio frequency components.
18
ASM along with a K-band two- layer microstrip interdigital filter
exploiting aggressive space.
mapping.
It provides effective optimization
along with providing flexibility.
The insertion loss is slightly higher.
It can be used in wireless communication
industries.
19
Microstrip Bandpass Filters Using Fragment-
type Coupling Structure Based
on Multi- objective Optimization.
It provides flexibility and
diversity of fragment-type
structure.
It suffers from poor attenuation.
Filters can be used to design
microstrip bandpass
filters.
20
A unique technique called split-path method
in conjunction with optimum
curvature corrections.
It provides good estimation of curvature width
and the mean radius of the DGS structure.
Much calculation is not done.
Various BPF structures can be developed
using this technique.
23
Using Defected Ground Structure
(DGS) to Improve Non-
uniform Microstrip Bandpass Filters'
Performance.
It improves the performance of
filters.
Not much research has been
done.
It can be used for designing multi band
filter.
27
A compact dual band BPF with
substrate integrated waveguide
structure proposed. Two
sided loading provided with modified E- shaped DGS
technique.
It shows a quick move off, achieves great
selectivity of skirts, high seclusion of
interband, suppressed harmonics, and
reduced size.
Multiple band components with extremely
reduced size can be fabricated using this technique.
30
An UWB BPF designed with modified DGS techniques with attenuation of out
of band frequencies
The vital parameters viz.
insertion loss recorded (< 1 dB) at frequency
4.4-9.3 GHz.
Only a reasonable value is found between simulation and measurements.
It can be improved to develop hybrid
filters.
beyond its stopband.
4. Conclusion
This paper reviews different optimization techniques for selecting optimal parameters in microstrip bandpass filter design. Some channels show some highlights that are not too bad. We often involve soak passband slants, transmission zeroes at small frequencies in general. The frequencies of the zero transmission are certainly not difficult to control as the zeroes appear at the resonation frequencies of the quarter -wavelength. It has been shown that the semi-TEM estimate and TLT are sufficient to display the channel presentations; however, the discontinuities of the microstrip should be scrutinized carefully. A bandpass recurrence is a huge part to be found in recurrence arranged using a mixture of impedance low-pass phase frequency (LPF) and the perfect high-pass frequency (HPF). By tuning the estimate of tallness, length and width of the DGS unit cell, a broad tuning range of 0.64 GHz are produced. This channel results in a loss of expansion of -0.42 dB due to the segments present in addition to the loss of arrival of -12.31 dB and-3 dB of 0.92 GHz. [22] presents the point of view of the participant and a detailed description of the microstrips of the surrendered ground system (DGS). DGS is powered by electromagnetic/photonic bandgap (EBG / PBG) structures and metamaterials used i n microwave components to achieve a variety of performance enhancement highlights. Due to its simple auxiliary program, the microwave component with Defected Ground Structure (DGS) increased performance between each of the systems expected to upgrade the parameters and chiselled holes or imperfections on the territory component of the base plane of the microstrip circuit called the Defected Ground Structure. Single or multiple deformities can also be known as DGS on the base plane. Stomach muscle Initio DGS has been reputed under the microstrip row for channels. Under the microstrip row, DGS was used to achieve band-stop attributes and suppress lower mode music and common coupling. At the time when sure-fire execution of DGS within the channel field, DGS is widely sought for changed applications today.
References
[1] Alaydrus, M. (2010). Designing microstrip bandpass filter at 3.2 GHz. International Journal on Electrical Engineering and Informatics, 2(2), 71-83.
[2] Hennings, A., Semouchkina, E., Baker, A., & Semouchkin, G. (2006). Design optimization and implementation of bandpass filters with normally fed microstrip resonators loaded by high-permittivity dielectric. IEEE transactions on microwave theory and techniques, 54(3), 1253-1261.
[3] Abbosh, A. M. (2011). Design method for ultra-wideband bandpass filter with wide stopband using parallel-coupled microstrip lines. IEEE Transactions on Microwave Theory and Techniques, 60(1), 31-38.
[4] Gupta, P., & Bhatia, D. (2014, August). Bandpass filter using short circuited stubs for mobile Wi-Max application. In 2014 International Conference on Advances in Engineering & Technology Research (ICAETR-2014) (pp. 1-3). IEEE.
[5] Hsu, C. L., Hsu, F. C., & Kuo, J. K. (2005, June). Microstrip bandpass filters for ultra- wideband (UWB) wireless communications. In IEEE MTT-S International Microwave Symposium Digest, 2005. (pp. 4-pp). IEEE.
[6] Lu, J., Gu, H., & Wu, W. (2016, June). Design of a wideband bandpass filter with harmonic Suppression. In 2016 IEEE International Conference on Microwave and Millimeter Wave Technology (ICMMT) (Vol. 1, pp. 401-403). IEEE.
[7] Lotfi-Neyestanak, A. A., & Lalbakhsh, A. (2012). Improved microstrip hairpin-line bandpass filters for spurious response suppression. Electronics letters, 48(14), 858-859.
[8] Sharma, G., Dua, R. L., & Bhati, Y. (2013). A Review paper on Microstrip Bandpass Hairpin Filter. International Journal of Latest Technology in Engineering, Management
& Applied Science (IJLTEMAS), 2(3), 172-175.
[9] Bruster, A., Zakaria, Z., Ruslan, E., & Mutalib, M. A. (2015). A Review of Bandpass with Tunable Notch Microwave Filter in Wideband Application. International Journal of Engineering and Technology (IJET), 7(3), 825-832.
[10] Lai, M. I., & Jeng, S. K. (2006). Compact microstrip dual-band bandpass filters design using genetic-algorithm techniques. IEEE Transactions on Microwave Theory and techniques, 54(1), 160-168.
[11] Jeon, J., Kahng, S., & Kim, H. (2015). GA-optimized compact broadband CRLH band- pass filter using stub-inserted interdigital coupled lines. Journal of electromagnetic engineering and science, 15(1), 31-36.
[12] Naghavi, A. H., Tondro-Aghmiyouni, M., Jahanbakht, M., & Lotfi Neyestanak, A. A.
(2010). Hybrid wideband microstrip Wilkinson power divider based on lowpass filter optimized using particle swarm method. Journal of Electromagnetic Waves and Applications, 24(14-15), 1877-1886.
[13] Yun, Y. C., Oh, S. H., Lee, J. H., Choi, K., Chung, T. K., & Kim, H. S. (2015). Optimal design of a compact filter for UWB applications using an improved particle swarm optimization. IEEE Transactions on Magnetics, 52(3), 1-4.
[14] Lalbakhsh, A., Afzal, M. U., Esselle, K. P., & Zeb, B. A. (2015, November). Multi- objective particle swarm optimization for the realization of a low profile bandpass frequency selective surface. In 2015 International Symposium on Antennas and Propagation (ISAP) (pp. 1-4). IEEE.
[15] Zhan, A., Hu, Y., & Yu, M. (2018). Optimal Design of Microstrip Bandpass Filter in Ultra-wideband (UWB) Wireless Communication for Ship Based on Distributed Algorithm. Journal of Coastal Research, 83(sp1), 585-589.
[16] Dastkhosh, A. R., Dadashzadeh, G., & Sedaaghi, M. H. (2010). New design method of UWB microstrip filters using adaptive genetic algorithms with defected ground structures. International Journal of Microwave Science and Technology, 2010.
[17] Zhang, X., Zhai, Q., Li, Z., Ou, W., & Ou, Y. (2018). Design of a K-band two-layer microstrip interdigital filter exploiting aggressive space mapping. Journal of Electromagnetic Waves and Applications, 32(17), 2281-2291.
[18] Zhan, A., Hu, Y., & Yu, M. (2018). Optimal Design of Microstrip Bandpass Filter in Ultra-wideband (UWB) Wireless Communication for Ship Based on Distributed Algorithm. Journal of Coastal Research, 83(sp1), 585-589.
[19] Wang, L., Wang, G., He, Y., & Zhang, R. (2017, June). Design of microstrip bandpass filters using fragment-type coupling structure based on multi-objective optimization. In 2017 IEEE MTT-S International Microwave Symposium (IMS) (pp. 1620-1623). IEEE.
[20] Chakravorty, P., & Mandal, D. (2016). Microstrip bandpass filter design using split‐ path method and optimized curvature corrections. International Journal of Numerical Modelling: Electronic Networks, Devices and Fields, 29(3), 520-529.
[21] Khan, M. T., Zakariya, M. A., Saad, M. N. M., Baharudin, Z., & Rehman, M. U. (2014, June). Analysis and realization of defected ground structure (DGS) on bandpass filter. In 2014 5th International Conference on Intelligent and Advanced Systems (ICIAS) (pp. 1- 4). IEEE.
[22] Kumar, A., & Machavaram, K. V. (2013). Microstrip filter with defected ground structure: a close perspective. International Journal of Microwave and Wireless Technologies, 5(5), 589-602.
[23] Ala'a, I. H., Bataineh, M. H., Ahmad, I., Al-Zoubi, A. S., & Elmegri, F. (2017, September). Using defected ground structure (DGS) to improve nonuniform microstrip bandpass filters' performance. In 2017 Internet Technologies and Applications (ITA) (pp.
290-292). IEEE.
[24] Singh, P., & Tomar, R. (2014). The use of defected ground structures in designing microstrip filters with enhanced performance characteristics. Procedia Technology, 17, 58-64.
[25] Belmajdoub, A., Boutejdar, A., El Alami, A., Bennani, S. D., & Jorio, M. (2019). Design and optimization of a new compact 2.4 GHz-bandpass filter using DGS technique and U- shaped resonators for WLAN applications. Telkomnika, 17(3).
[26] Singh, P., & Tomar, R. (2014). The use of defected ground structures in designing microstrip filters with enhanced performance characteristics. Procedia Technology, 17, 58-64.
[27] Xu, S., Ma, K., Meng, F., & Yeo, K. S. (2015). Novel defected ground structure and two- side loading scheme for miniaturized dual-band SIW bandpass filter designs. IEEE microwave and wireless components letters, 25(4), 217-219.
[28] Boutejdar, A., Eltabit, N. M., Ibrahim, A. A., Burte, E. P., & Abdalla, M. A. (2016).
New Compact Dual Bandpass Filter Using Coupled Double-Ring Resonators and DGS- Technique. Applied Computational Electromagnetics Society Journal, 31(2).
[29] Chen, F. C., Hu, H. T., Qiu, J. M., & Chu, Q. X. (2015). High-selectivity low-pass filters with ultrawide stopband based on defected ground structures. IEEE Transactions on components, packaging and manufacturing Technology, 5(9), 1313-1319.
[30] Lee, J. K., & Kim, Y. S. (2010). Ultra-wideband bandpass filter with improved upper stopband performance using defected ground structure. IEEE Microwave and Wireless Components Letters, 20(6), 316-318.
[31] Song, Y., Yang, G. M., & Geyi, W. (2014). Compact UWB bandpass filter with dual notched bands using defected ground structures. IEEE Microwave and Wireless Components Letters, 24(4), 230-232.
[32] Sahu, B., Singh, S., Meshram, M. K., & Singh, S. P. (2018). Super-compact ultra- wideband microstrip band-pass filter with improved performance using defected ground structure-based low-pass filter. Journal of ElEctromagnEtic WavEs and applications, 32(5), 635-650.
[33] Rekha, T. K., Abdulla, P., Jasmine, P. M., & Raphika, P. M. (2018). Improved frequency response of microstrip lowpass filter using defected ground structures. Progress In Electromagnetics Research, 81, 31-40.
[34] Sahu, B., Singh, S., Meshram, M. K., & Singh, S. P. (2018). Study of compact microstrip lowpass filter with improved performance using defected ground structure. International Journal of RF and Microwave Computer‐ Aided Engineering, 28(4), e21209.
[35] Zheng, X., Pan, Y., & Jiang, T. (2018). UWB Bandpass Filter with Dual Notched Bands Using T-Shaped Resonator and L-Shaped Defected Microstrip Structure.
Micromachines, 9(6), 280.
[36] Fan, J., Zhan, D., Jin, C., & Luo, J. (2012). Wideband microstrip bandpass filter based on quadruple mode ring resonator. IEEE Microwave and Wireless Components Letters, 22(7), 348-350.
[37] Zhao, J., Wang, J., Zhang, G., & Li, J. L. (2013). Compact microstrip UWB bandpass filter with dual notched bands using E-shaped resonator. IEEE Microwave and Wireless Components Letters, 23(12), 638-640.
[38] Marimuthu, J., Abbosh, A. M., & Henin, B. (2013). Planar microstrip bandpass filter with wide dual bands using parallel-coupled lines and stepped impedance resonators.
Progress In Electromagnetics Research, 35, 49-61.
[39] Marimuthu, J., Abbosh, A. M., & Henin, B. (2013). Planar microstrip bandpass filter with wide dual bands using parallel-coupled lines and stepped impedance resonators.
Progress In Electromagnetics Research, 35, 49-61.
[40] Lu, H., Huang, J., Zhang, X., Yuan, N., & Huang, Z. (2016, October). Dual-Mode Dual- Band Microstrip Bandpass Filter Based on Stepped Impedance Resonator (SIR) for Wireless Communication Applications. In International Conference on Communication and Electronic Information Engineering (CEIE 2016). Atlantis Press.
[41] Hasan, M. F., Jalal, A. S. A., & Ahmed, E. S. (2017, May). Compact dual-band microstrip band pass filter design based on stub loaded resonator for wireless applications. In 2017 Progress In Electromagnetics Research Symposium-Spring (PIERS) (pp. 1810-1814). IEEE.
[42] Mezaal, Y. S., & Al-Zayed, A. S. (2019). Design of microstrip bandpass filters based on stair-step patch resonator. International Journal of Electronics, 106(3), 477-490.
[43] Mezaal, Y. S., & Ali, J. K. (2016). Investigation of dual-mode microstrip bandpass filter based on SIR technique. PLoS one, 11(10), e0164916.
[44] Namsang, A., & Akkaraekthalin, P. (2010). Microstrip bandpass filters using end- coupled asymmetrical step-impedance resonators for wide-spurious response. Progress In Electromagnetics Research, 14, 53-65.
[45] Gorur, A. K. (2018). A Novel Compact Microstrip Balun Bandpass Filter Design Using Interdigital Capacitor Loaded Open Loop Resonators. Progress In Electromagnetics Research, 76, 47-53.
[46] Cheng, T., & Tam, K. W. (2017). A wideband bandpass filter with reconfigurable bandwidth based on cross-shaped resonator. IEEE Microwave and Wireless Components Letters, 27(10), 909-911.
[47] Bi, X. K., Cheng, T., Cheong, P., Ho, S. K., & Tam, K. W. (2018). Design of dual-band bandpass filters with fixed and reconfigurable bandwidths based on terminated cross- shaped resonators. IEEE Transactions on Circuits and Systems II: Express Briefs, 66(3), 317-321.
[48] La, D. S., Xu, J., Zhang, B. Y., & Jia, S. Q. (2018, July). Compact Wideband Microstrip Parallel-coupled Line Band-pass Filter with Complementary Electric Field Coupled Resonators. In 2018 International Applied Computational Electromagnetics Society Symposium-China (ACES) (pp. 1-2). IEEE.
[49] Lu, H., Wu, W., Huang, J., Zhang, X., & Yuan, N. (2017). Compact dual-mode microstrip bandpass filter based on Greek-cross fractal resonator. Radioengineering, 26(1), 275.
[50] Abouelnaga, T. G. M. A., & Mohra, A. S. (2017). Novel compact harmonic-rejected ring resonator based bandpass filter. Progress In Electromagnetics Research, 74, 191-201.
[51] Mezaal, Y. S., Eyyuboğlu, H. T., & Ali, J. K. (2014). New microstrip bandpass filter designs based on stepped impedance Hilbert fractal resonators. IETE Journal of Research, 60(3), 257-264.
[52] Parvez, S., Sakib, N., & Mollah, M. N. (2015, May). Advanced investigation on EBG structures: A critical analysis to optimize the performance of asymmetric couple-line
bandpass filter. In 2015 International Conference on Electrical Engineering and Information Communication Technology (ICEEICT) (pp. 1-6). IEEE.
[53] Mezaal, Y. S., & Eyyuboglu, H. T. (2016). Investigation of new microstrip bandpass filter based on patch resonator with geometrical fractal slot. PloS one, 11(4), e0152615.
[54] Yazdanpanahi, M., & Mirshekar-Syahkal, D. (2012, January). Millimeter-wave liquid- crystal-based tunable bandpass filter. In 2012 IEEE Radio and Wireless Symposium (pp.
139-142). IEEE.
[55] Torrecilla, J., Urruchi, V., Sánchez-Pena, J., Bennis, N., García, A., & Segovia, D.
(2014). Improving the pass-band return loss in liquid crystal dual-mode bandpass filters by microstrip patch reshaping. Materials, 7(6), 4524-4535.
[56] Gillette, S. M., Geiler, A. L., Chen, Z., Chen, Y., Arruda, T., Xie, C., & Vittoria, C.
(2011). Active tuning of a microstrip hairpin-line microwave bandpass filter on a polycrystalline yttrium iron garnet substrate using small magnetic fields. Journal of Applied Physics, 109(7), 07A513.
[57] Azad, I., Bhuiyan, M. A. H., & Mahbub, S. Y. (2013). Design and performance analysis of 2.45 GHz microwave bandpass filter with reduced harmonics. International Journal of Engineering Research and Development, 5(11), 57-67.
[58] Seok, S., & Kim, J. (2013). Design, fabrication, and characterization of a wideband 60 GHz bandpass filter based on a flexible PerMX polymer substrate. IEEE Transactions on Components, Packaging and Manufacturing Technology, 3(8), 1384-1389.
[59] Zhang, D. D., Zhou, L., Wu, L. S., Qiu, L. F., Yin, W. Y., & Mao, J. F. (2014). Novel bandpass filters by using cavity-loaded dielectric resonators in a substrate integrated waveguide. IEEE Transactions on Microwave Theory and Techniques, 62(5), 1173- 1182.
[60] Liu, Y., Jiang, D., Xia, L., & Xu, R. (2015). A novel microwave tunable band-pass filter integrated power divider based on liquid crystal. International Journal of Antennas and Propagation, 2015.
Authors
Hussain Bohra* received his B.E. degree in Electronics and Communication Engineering from Rajasthan University (RU), Jaipur, India, in 2007 and M.Tech degree in Digital Communication from Rajasthan Technical University (RTU), Kota, India, in 2015. Currently, he is pursuing his Ph.D. degree with the Department of Electronics and Communication Engineering, Sir Padampat Singhania University (SPSU), Bhatewar, Udaipur, India. His primary areas of research interests include ultra-wideband technology, wireless networks, microwaves and antennas propagation.
