UWB Applications Research Articles

A low-noise voltage-controlled ring oscillator in 28-nm FDSOI technology for UWB applications

In millimeter wave systems, performance degradation mainly occurs due to high phase noise of voltage-controlled oscillators (VCOs). This paper proposes a low power, low phase noise ring-VCO developed for ultra-wide band applications identified for possible 5G usage. For this purpose, a novel differential symmetrical load delay cell based 3-stage ring oscillator has been introduced to design the ring-VCO. The 28 nm CMOS Fully Depleted Silicon On Insulator (FDSOI) technology is adopted for designing this VCO circuit with 1 V power supply while a new voltage control through the transistor body bias is implemented. The simulated results show that the proposed oscillator works in the tuning range of 29–49 GHz and dissipates 3.75 mW of power. It exhibits a phase noise of −129.2 dBc/Hz at 1 MHz offset from 49 GHz oscillation frequency, and a remarkable Figure of Merit (FoM) of −217.26 dBc/Hz. With similar power supply, the phase noise rises to −93.16 dBc/Hz for a second oscillator involving more of active components exactly 9 delay cells. Further, the impact of the operation temperature variation on the VCO performance is investigated. Results show a drift in the oscillation frequency for a temperature step from 27 °C to 40 °C and a degradation of 3dBc in the phase noise performance.

Parametric study and Analysis of Band Stop Characteristics for a Compact UWB Antenna with Tri-band notches

In this article, equivalent circuit modeling with study and analysis of band notch characteristics for a triple band notched UWB antenna has been discussed to develop a better understanding of the antenna functioning and its behavior. Â A small square ultra wideband antenna having overall size of 24 x 31 mm 2 with tri- band rejections is designed and simulated using HFSS software. Very narrow band notching is accomplished by placing C slots and inverted C slot of different dimensions on the radiating patch which makes maximum space utilization without performance deterioration. The antenna operates from 3.1 to 14 GHz (VSWR 2) of 3.3- 3.7 GHz (WiMAX), 5.1 - 5.4 GHz (Lower WLAN and HIPERLAN/2) and 5.7 6 GHz (Upper WLAN) as shown by the simulated and measured results (VSWR<2) of the UWB antenna, with and without the presence of triple notches, thus utilizing the maximum UWB bandwidth. The radiation pattern plots for simulated and measured results are also presented to validate the working of the antenna. This antenna can be a respectable candidate for future European and USA high capacity UWB applications. The group delay and peak gain plots are also found to be stable in the range of operation of the antenna. The study and analysis of the band notching is discoursed in terms of current distribution and impedance plots to provide a greater and better perception into the working of the antenna and hence an equivalent circuit for the tri-band notched UWB antenna has been proposed.

Design and analysis of a compact WiMAX and WLAN band notched planar monopole antenna for UWB and bluetooth applications

In this manuscript, a compact UWB with dual band-notched planar monopole antenna is investigated. The band notched characteristics at WiMAX and WLAN is obtained by connecting two pairs of stubs to the modified ground plane. The size of proposed antenna is 25(W) × 30(L) × 1.6(H) mm3 which consists of a fork shaped structure as a main radiating element and excited with a 50-Ω microstrip line. The proposed antenna covers Bluetooth frequency band (2.4-2.48 GHz) along with UWB spectrum without increasing the size of the antenna. The measured operating frequency of the proposed antenna is from 2.4 to 12.8 GHz along with WiMAX and WLAN band-notched. Moreover, the measured gain of the proposed antenna varies between 2 and 6 dBi except notched band. At notched frequencies, it is −1 and −6 dBi at WiMAX and WLAN, respectively. The total antenna efficiency varies from 80% to 95% except notched frequency bands. The radiation patterns and time domain characteristics are also analyzed and found suitable for the modern UWB applications. Finally, a prototype of dual band-notched antenna is manufactured and its characteristics are measured using network analyzer. The simulated and measured results are found in close agreement.

Multiband Printed Loop Antenna for UWB Applications

Multiband Printed Loop Antenna for UWB Applications

Analysis and Design of a Multi Octave Circularly Polarized Monopole Antenna for UWB, X and Ku-Band Applications

This work presents a circularly polarized, CPW-Fed multi band operating monopole antenna. The monopole antenna consists of three parasitic elements, along with a stub at ground for impedance matching. The parasitic elements so far accumulated have shown their excellence in increasing the impedance bandwidth over the 6-18GHz band. The antenna was carved on FR-4 epoxy substrate which result a copper clad laminated structure. The CPW-Fed monopole antenna exhibits excellent circular polarization levels in the frequency region 6-18GHz. The simulation resulted a Return loss of less than -10dB, with good axial ratio less than -3dB over entire band of interest. The simulation was carried out through HFSS microwave studio. The antenna measured values are in good correspondence to the simulated values.

Design Of A New Ultra Wideband (Uwb) Microstrip Antenna

Background/Objectives: Employing an antenna with the structure of heptagon patch and proper slots to reduce the size of the antenna while keeping the UWB bandwidth. Methods/Statistical Analysis: All the simulations have been done using HFSS software. The geometries of the antenna were determined by implementing parametric studies using this software. In the designed antenna, uniform ground plane prevents back lobs in radiation pattern and makes it suitable for some applications such as medical usages. Findings: Through this design, an antenna that is applied for UWB application can be achieved with a low cost and can be fabricated on a simple substrate. Not only does it cover a favorable bandwidth, but also has a new shape for its patch. The antenna’s small size, desired bandwidth with acceptable gain in comparison to previously designed or fabricated antennas can make it a good candidate for future analyses. Another benefit of this designed antenna is employing probe feeding technique to improve bandwidth as well as other related parameters of UWB antennas. Application/Improvements: All the simulations have been done using HFSS (high frequency structural simulator) software. Keywords: Bandwidth, Microstrip Antenna, Ultra Wideband

Rectangular Monopole Antenna with U-notches for UWB Applications

Rectangular Monopole Antenna with U-notches for UWB Applications

Metamaterial‐based compact UWB planar monopole antennas

AbstractIn this article, novel compact UWB antennas based on loading of via less composite right/left‐handed (CRLH) unit cells are presented. Two novel metamaterials (MTM)‐based CRLH‐TL unit cells have been designed. The dispersion characteristics of the proposed unit cells are numerically calculated which follows CRLH properties. We designed a via‐free version of the CRLH unit cell by using virtual ground concept which simplifies the fabrication process and decreases the costs. The additional impedance matching network has been eliminated by using the optimum location of feed offset. The resulting double via less CRLH unit cells loaded antenna's bandwidths are improved by proper realizing the unit cell parameters and merging of ZOR mode to other lower and higher order modes. The proposed antennas have compact dimension 25 × 15 × 1.6 mm3. The two proposed antennas have UWB characteristics such as 109% and 125% fractional bandwidth, respectively. The measured gain and efficiency have been obtained with desired values for UWB applications. Good agreement has been observed between simulated and measured results.

Design of Triband Vivaldi Antenna for UWB Application

Design of Triband Vivaldi Antenna for UWB Application

Super‐wideband CPW fed modified square monopole antenna with stabilized radiation characteristics

AbstractThis article explores the design and analysis of a CPW fed modified square monopole antenna for super wideband (SWB) application. Three key features of proposed radiating structure are: (1) semi‐circular base provides smother impedance variation and helpful in the creation of more than decade (10:1) impedance bandwidth (super‐wideband); (2) modified square shaped monopole reduce the lower frequency of operation and create larger BDR value (7871.49); (3) trimmed edges provide stabilized radiation characteristics even at higher frequencies. In order to endorse the simulated outcomes, prototype of proposed antenna structure is fabricated and tested. Good settlement is to be found between measured and simulated outcomes. From experimental results, it confirms that the proposed radiator is operating over more than decade (14.52:1) bandwidth that is, 0.95‐13.8 GHz (VSWR &lt; 2). Time domain analysis of proposed radiator also supports its applicability for SWB applications. The proposed radiator is quite appropriate for different wireless applications such as Amature Radio, Digital Audio Broadcasting, ISM, Wi‐Fi, GPS, Bluetooth, WLAN, and UWB applications.

A new CPW‐fed broadband circularly polarized printed monopole antenna for UWB application

AbstractA new coplanar‐waveguide (CPW) ‐fed circularly polarized (CP) printed monopole Antenna with a simply structure is presented. By utilizing an asymmetrical T‐shaped matching stub as feedline and nesting two strips of inverted‐L‐shaped and rectangle into both sides of the ground plane along the edge of the substrate, good impedance matching and CP radiation can be obtained. The proposed antenna is tested and its measured result is fairly identical with the simulated result. It exhibits that the impedance bandwidth for S11&lt;−10 dB is as large as 115% (3.1–11.9 GHz) which can apply to the UWB communication. The 3‐dB axial‐ratio bandwidth (ARBW) reaches 62.6% from 3.4 GHz to 6.5 GHz.

Compact Design of Modified Pentagon Shaped Monopole Antenna for UWB Applications

Compact Design of Modified Pentagon Shaped Monopole Antenna for UWB Applications

Ultra-Low-Jitter Fully Tunable Baseband Pulse Generator for UWB Applications

A fully tunable baseband ultra-wideband pulse generator realized with commercial off-the-shelf components is presented. It is made of high-speed logic gates and comparators, and it is compliant with the current-mode logic digital standard. The pulse emitted power and bandwidth are tunable with pulsewidth and amplitude variation, which shows high flexibility. This advantage simplifies the design of the downstream shaping network, as so to be compliant with international regulations. A differential output with very low jitter is demonstrated.

Compact microstrip feed dual band monopole antenna for UWB and bluetooth applications

Compact microstrip feed dual band monopole antenna for UWB and bluetooth applications

Tree shaped fractal antenna with multiband characteristics

A tree shaped fractal antenna with U shaped slot and W-shaped slot has been designed and analyzed in this article by using ANSYS elec-tromagnetic desktop 17. The proposed antenna is analyzed taking FR4 substrate is taken as the substrate material. The proposed antenna exhibits multiband characteristics (2.75-3.17GHz, 4.1-4.8GHz, 5.1-5.3GHz and 5.4-6.3GHz, 7.21-12.8GHz) in the Ultra-wide band region. The path that is radiating by superposition of the rectangular patches and multiple-band operating frequency is obtained by increasing the U-shapes slots and w-shaped slot on the patch. The improvement in the impedance characteristics between the adjacent frequencies is achieved by using defected ground structure (DGS) on the ground plane as to cover the region of UWB application (3.1-10.6GHz). The proposed antenna works in the applications like Wi-Max, Weather forecasting RADAR systems and WLAN.

A compact dual port UWB-MIMO/diversity antenna for indoor application

A compact printed quadrant shaped monopole antenna is introduced in this paper as a good prospect for ultra wideband- multiple-input multiple-output (UWB-MIMO) system. The proposed MIMO antenna comprises two perpendicularly oriented monopoles to employ polarization diversity. An open circuit folded stub is extended from the ground plane of each radiating element to enhance the impedance bandwidth satisfying the UWB criteria. Two ‘L’ shaped slots are further etched on the radiator to provide good isolation performance between two radiators. The desirable radiator performances and diversity performances are ensured by simulation and/or measurement of the reflection coefficient, radiation pattern, realized peak gain, envelope correlation coefficient (ECC), diversity gain, mean effective gain (MEG) ratio and channel capacity loss (CCL). Results indicate that the proposed antenna exhibits 2.9–11 GHz 10 dB return loss bandwidth, mutual coupling &lt;−20 dB, ECC&lt;0.003, MEG ratio≈1, and CCL&lt;0.038 Bpsec/Hz, making it a good candidate for UWB and MIMO diversity application.

Design of inside cut von koch fractal UWB MIMO antenna

An Inside Cut Hexagonal Von Koch fractal MIMO antenna is designed for UWB applications and its characteristics behaviour are studied. Self-comparative and space filling properties of Koch fractal structure are utilized in the antenna design which leads to the desired miniaturization and wideband characteristics. The hexagonal shaped Von Koch Fractal antenna with Defected Ground Structure (DGS) is designed on FR4 substrate with a compact size of 30mm x 20mm x 1.6mm. The antenna achieves a maximum of -44dB and -51dB at 7.1GHz for 1-element and 2-element case respectively.

Low cross-polarization antipodal tapered slot antenna with gain bandwidth enhancement for UWB application

The problems for the antipodal tapered slot antenna (ATSA) with impedance bandwidth greater than 10:1 including main beam tilt and split, high cross-polarization component, and low gain at high frequencies narrow its gain bandwidth. The concept of a dielectric sheet-covered ATSA (DATSA) exploiting the coupling between the antenna and dielectric sheets is adopted to solve the issue. The original ATSA and proposed DATSA are simulated, fabricated and tested. The simulated results show good agreement with the measured results. In the range of 3.68–50 GHz, S11 of both antennas are less than −10 dB. Measured far-field results present the DATSA could generate well-formed end-fire beam with low cross-polarization of less than −13 dB and achieve boresight gain of more than 10 dBi over the range of 10–22 GHz, more than 14.6 dBi over the range of 23–30 GHz, more than 16.5 dBi over the range of 31–40 GHz, and more than 14 dBi over 41–50 GHz. Compared to the ATSA, the average boresight gain increase of 5.45 dBi is achieved in the range of 10–50 GHz.

Circular antennaUWB microstrip line feeding planar modified

In this paper we have investigated compact printed semicircular disc monopole antenna, which is basically printed microstrip antenna with etched ground plane for UWB applications. In particular we have simulated very compact semicircular disc monopole antennas for UWB communication. Simple rectangular microstrip line is used for feeding the printed monopole antenna and its frequency bandwidth under -10dB return loss is ranging from 3GHz to 11.6 GHz. This compact printed monopole antenna works well for the whole UWB frequency band 3.1-10.6GHz.

Circular slotted monopole printed antenna with grounded stub WLAN band-notch for UWB applications

ABSTRACTThis paper presents compact printed UWB antenna (2.75–16.5 GHz) with WLAN band-notch at 5.75 GHz (4.1–7.1 GHz), the overall size of the antenna (46 × 27) mm2 base on FR-4 substrate with relative permittivity 4.4 and low profile of 1.6 mm, the gain has maximum value of 4.5dBi and minimum value of −3.32dBi at 12.5 GHz and Band-Notch frequency 5.75 GHz, respectively, with very good radiation pattern characteristic has been achieved.