Design of microstrip monopoles for broadband systems using an iterative wave formulation

Green's function and finite element methods were used to investigate the propagation characteristics of a conventional rectangular waveguide with an enclosed septum. Derivatives of this structure will ultimately be used to form laterally closed TEM horn antennas. Conditions were determined which would guarantee single mode TEM operation. A waveguide impedance for this mode of operation, which is frequency independent and possesses the characteristics of the conventional transmission line impedance, was defined and computed for a range of variables. Such devices will find applications in ultra-wideband systems.

We present the analysis and design of an inductorless wide-band SiGe heterojunction bipolar transistor low-noise amplifier (LNA) using a resistive feedback scheme for application in ultra-wideband systems. Multiple feedback loops enable sufficient gain and low noise figure, and is competitive with conventional narrow-band cascode LNAs using an emitter degeneration inductor. Measurement results show 20-dB gain with 1-dB variation over 3-10 GHz, and a matched input and output with less than -10-dB reflection. The minimum noise figure is 3.05 dB at 3 GHz and increases to 4.5 dB at 10 GHz. For the analysis and design of such wide-band amplifiers, analytical expressions describing the basic performance tradeoffs are derived and verified with simulation and measurements. General design procedures are also given in this paper in order to better understand the roles of the various critical components in the amplifier.

In this paper, the concentric circular ring arc patch antenna is presented. The circular ring slots and arc slot is presented in circular patch. The proposed antenna is resonated at two frequencies are 13 GHz, 16.6 GHz with return loss −24.9 dB and −27 dB for Ku band applications. The maximum gain of resonant frequencies are 3.84 dB, 3.94 dB. The co polarization and cross polarization of E plane and H plane and impedance bandwidth of proposed antenna measured at resonant frequencies.

A review: The influence of graphene material integration in antenna characteristics in the presence of bias for fifth and sixth generation wireless communication application

A novel low-cost low-power fully integrated tunable transmit module composed of a tunable CMOS monocycle pulse generator and compact uniplanar antenna was designed, built, and tested for ultra-wideband (UWB) impulse systems. The CMOS tunable pulse generator integrates a tuning delay circuit, square-wave generator, impulse-forming circuit, and pulse-shaping circuit in a single chip using a standard low-cost 0.25-mum CMOS process. It can generate a monocycle pulse and Gaussian-type impulse (without the pulse-shaping circuitry) signals with tunable pulse duration. A compact uniplanar UWB antenna was also developed and integrated directly with the CMOS pulse generator chip to form the complete integrated tunable UWB transmit module. Measured results show that the CMOS tunable pulse generator can produce a 0.3-0.6-V peak-to-peak monocycle pulse with 140-350-ps tunable pulse duration and a 0.5-1.3-V peak-to-peak impulse signal with 100-300-ps tunable pulse-duration, and the uniplanar antenna has less than a 18-dB return loss and is suitable for transmitting/receiving UWB time-domain impulse signals covering the entire UWB bandwidth of 3.1-10.6 GHz. Good agreement between measured and calculated performance is also achieved. The UWB transmit module was experimentally characterized and its performance is verified. This UWB module finds applications in various time-domain UWB systems including wireless communications and radar

This work presents the frequency response analysis of a planar band pass filter using the WCIP method. The filter geometry is composed of a rectangular microstrip patch with a perforated complementary split ring resonator (CSRR). The investigation of the filter properties is done considering the perforated patch geometry printed on isotropic and anisotropic substrates. Simulations results are determined by WCIP method and HFSS software, for comparison purpose, for the filter resonant frequency, bandwidth, return loss, and insertion loss. A prototype of the proposed band pass filter printed on isotropic substrate was fabricated and measured. Simulation (WCIP and HFSS) and measurement results are in good agreement.

Wave concept iterative procedure (WCIP) is used for the determination of scattering characteristics of single and double metallic ring frequency selective surfaces (FSS). In the WCIP method, the analysis of the FSS is reduced to that of the unit cell. Basically, the WCIP method consists of scattering the incident waves at the interface and the reflection of the scattered waves by the closing ends of the periodic wall box containing the FSS unit cell. The use of the two dimensional fast Fourier transform algorithm results in a reduction of the running time and memory space. FSSs based on single and double metallic rings are analyzed by the WCIP method. A good agreement is observed between the WCIP results and the experimental results. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1324–1328, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23383

This paper presents the effect on resonant frequency of multilayer circular annular ring microstrip antenna. Three nearly circular annular ring microstrip antennas (ARMSA) have been fabricated on FR4 substrate of dielectric constant 4.3 and thickness 1.53mm of various dimensions. Experimental resonant frequency of simple circular ARMSA, covered circular ARMSA, spaced dielectric circular ARMSA and circular ARMSA with two superstrates have been measured and compared with the calculated resonant frequency from full wave analysis. The average % deviation of all these ARMSA are respectively found as -0.278%, 1.03%, -0.535% and 0.5%. The measured and calculated resonant frequencies are in good agreement. The Simple nearly circular ARMSA, fed diagonally at the center of the radiating patch is studied for circular polarization (CP) with 3dB Axial Ratio bandwidth. The three types of ARMSA has been designed and fabricated and found to have a CP-3 dB axial ratio bandwidth of 5.2%, 4.16% and 2.06% at their center fundamental resonant frequency. This type of study is useful for wideband, high gain antenna and to calculate the radome and environmental effect on resonant frequency.

In this paper, a compact monopole wideband antenna is designed and manufactured for ultra-wide band (UWB) applications. In order to extend the impedance bandwidth of the proposed antenna, rectangular and triangular slots are etched from the partial ground and from the center of the rectangular patch respectively. Also, by cutting the lower corners of the radiating patch using stepped technique, additional resonances are regenerated and lead to further improvement in the covered bandwidth. The proposed patch antenna has advantageous of compactness its overall size equals 40 × 40 mm2.Simulated and measured results show that the proposed antenna design exhibits a bandwidth from 2.9 – 19.2 GHz for VSWR< 2. The antenna structure provides a wide usable fractional bandwidth of 148%. These inherent characteristics of the proposed antenna make it suitable for efficient transmission and reception in UWB systems. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:1514–1519, 2016

A CPW-fed circular wide slot UWB antenna with C-band, WLAN and X-band notch functions has been presented in this article. The two stop bands are obtained by etching an isosceles triangular resonator with an inner isosceles triangular stub in the circular radiation patch and a stepped impedance resonator with an inner stub in the CPW fed transmission line. The two notched bands can be tuned by changing the dimensions of isosceles triangular, stepped impedance resonator and the inner stubs to give tunable notched band functions. The proposed dual notched band UWB antenna has been designed in details and optimized by means of HFSS. The proposed antenna has a small size of 32x24x1.6mm3. The simulated and measured results show that the designed UWB antenna has an impedance bandwidth of 10.7GHz covering the frequency band from 2.8GHz to 13.5GHz for voltage standing-wave ratio (VSWR) less than 2, except the notch bands 4.0GHz-5.4GHz for C-band and WLAN, 8.2GHz-9.3GHz for X-band which are used in satellite and military communications. The article also refers some recent patents on UWB antenna design. Keywords: Notch band, isosceles triangular resonator, stepped impedance resonator, UWB antenna, ANTENNA STRUCTURE, Impedance bandwidth, designed antennas

The growth of wireless and mobile communication has necessitated the development of efficient antennas with low return loss and wider bandwidth. Under this scenario, paper focuses on an efficient design of circular microstrip antenna at 5.8GHz for wide-band applications. In the design circular patch is mounted on RT/Duroid 5880 glass microfiber reinforced PTFE composite substrate material. A circular slot is etched on the circular patch to provide wide-band operation. Antenna designs are simulated and analyzed by finite element method (FEM) based structural simulator (HFSS™ simulator software). The antenna is designed to operate in C band with low return loss, high bandwidth and desirable voltage standing wave ratio (VSWR). Results of the proposed antenna structure shows a low return loss of −43db with a wider bandwidth of 270MHz and optimum VSWR.

A design approach to miniaturized, dual-resonant microstrip circular sector patch antenna with tilted circularly polarized (CP) beam is proposed. As mathematically laid down at first, the range of an asymmetric multiresonant prototype dipole’s length should be set as the positive odd-integer multiples of one-quarter wavelength, such that the resonant frequency could be accordingly reduced by one-half to the symmetric case. In this way, an asymmetric circular sector patch radiator can then be employed to realize a unique tilted CP beam by simultaneously exciting two orthogonal, odd-order resonant modes via proper perturbations. As numerically and experimentally validated, dual-resonant microstrip antennas with compact patch, flared angles of 330°/270°, impedance bandwidth of 26.6%/35.8%, and tilted CP 3 dB axial ratio (AR) bandwidth of 7.3%/12.0% can be realized on single-layered, air substrate with a height no more than 0.07 wavelength. It is evidently verified that the proposed approach should be effective for reducing patch size, enhancing impedance bandwidth and realizing tilted CP beam without increasing antenna profile, inquiring multiple radiators or employing reactance compensation techniques.

With increasing radio spectrum being allocated to wireless communications, multiband and ultrawideband systems are becoming much more prevalent. Such broadband systems are susceptible to interference, or can inadvertently radiate out-of-band emissions, so significant filtering is required at RF front-ends. With this motivation, a broadband conical monopole antenna with integrated tunable notch cavity filters is presented. The antenna is a complex structure but it can be conveniently realized with lightweight perforated alloy surfaces using 3-D printing. This coax-fed antenna is demonstrated to maintain its omnidirectional azimuthal pattern with a very wide notch-tuning range, resulting in a versatile broadband antenna.

A novel aspect in cross-polarization (XP) reduction in probe-fed circular microstrip patch antenna has been proposed employing a pair of symmetric circular clusters of shorting pins (CCSP) peripherally located along the radius of the patch. The proof of the concept is first established using a pair of shorting pins located symmetrically on the circular patch. Once the optimum position of the shorting pins for maximized XP reduction was identified, the design was modified by replacing an individual shorting pin using multiple numbers of shorting pins arranged in a circular geometry that is defined as CCSP. Effect of the incorporation of the CCSP structures on the antenna characteristics like resonance frequency, co-polarized radiation, and cross-polarized radiation has been studied extensively. The design concept has been discussed and experimentally established using simulated and measured results of the CCSP integrated circular patch over conventional circular patch for S-band. The integration of CCSP resulted in a relative suppression in XP levels of around 51 dB at the boresight and an average of 30 dB around ±60° on either side of the boresight in both the principal radiation planes.

In this paper, two identical Cylindrical Dielectric Resonator Antennas (CDRA) are stacked together to achieve Circular Polarization (CP). Ultra wideband impedance bandwidth and wide axial ratio bandwidth is achieved by three factors: stacking of similar DRs, stepped conformal microstrip feed line which will generate orthogonal modes and new partial ground plane with circular rings. Measurement results show that the proposed stacked Cylindrical CPDRA achieves an Impedance Bandwidth (IBW) of (S11 < −10 dB) of 72.48% (3.65–7.8 GHz) and Axial Ratio Bandwidth (ARBW) (AR <3 dB) of 44.12% (4.38–6.86 GHz), respectively. In addition, the proposed antenna shows dominant Left Hand CP with gain ranges from 1.4 to 6.5 dBic with maximum radiation efficiency of 93.3%. The advantages and novel points of proposed research work is as follows: (i) The novel configuration of stacking CDRA's along with stepped microstrip feed enhances ARBW, (ii) New proposed partial ground plane with two circular rings provides enhancement in IBW, (iii) Simple design and small height of DRs produces enhanced IBW, ARBW, Gain and Efficiency. Furthermore, by changing the position of circular rings on ground plane, the proposed antenna provides dominant LHCP to RHCP conversion and achieves polarization reconfigurability. The proposed antenna configuration covers the frequency range of applications of C-band and military satellite communication.