scholarly journals Directivity Enhancement of a Broadband Printed Antenna by Using Two Closely Spaced Strips

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Jiangniu Wu ◽  
Jing Sun ◽  
Jinyong Fang
Keyword(s):  
Frequency Band ◽  
Building Block ◽  
Electromagnetic Waves ◽  
Operating Frequency ◽  
Impedance Bandwidth ◽  
Type B ◽  
Printed Antenna ◽  
Printed Antennas ◽  
Outer Strip ◽  
Better Than

The bandwidth of a printed rectangular loop antenna with two gaps can be enlarged by using the metallic strips as directors. However, the directivity is not good. Because the two closely spaced metallic strips act as a building block, they can be used to block the propagation of electromagnetic waves. Therefore, two closely spaced metallic strips as a new reflector are adopted and investigated in this paper for improving the directivity of antenna. Two arrangement modes of the printed antennas with two closely spaced strips are designed, fabricated, and measured. Experimental results show that the impedance bandwidth of type A antenna (with inner strip) is about 62.5% ranging from 2.3 to 4.39 GHz. In addition, the gain of 3.8–5.2 dBi and 2 dB improvement of F/B ratio are achieved. Type B antenna (with outer strip) can realize a 62% measured bandwidth ranging from 2.29 to 4.35 GHz. Also, about 3.4 to 4.9 dBi of gain with 2.5 dB improvement of F/B ratio is obtained. The measured F/B ratios of the two modified antennas are both better than 10 dB within the operating frequency band. Measured results verified that adopting the two closely spaced metallic strips as a new reflector can both enhance the F/B ratio and gain without changing the overall dimensions and operating frequency.

scholarly journals Dual Notched-Band Crescent Moon Dielectric Resonator Antenna

2021 ◽  
Vol 25 (1) ◽  
pp. 11-19
Author(s):  
Mohamed Debab ◽  
◽  
Amina Bendaoudi ◽  
Zoubir Mahdjoub ◽  
◽  
...  
Keyword(s):  
Frequency Band ◽  
Dielectric Resonator ◽  
Satellite Communication ◽  
Ground Plane ◽  
Ultra Wideband ◽  
Dual Band ◽  
Impedance Bandwidth ◽  
Dielectric Resonator Antenna ◽  
Printed Antenna ◽  
Antenna Structure

In this article, a dual-band notched ultra-wideband (UWB) dielectric resonator antenna is proposed. The antenna structure consists of Crescent Moon Dielectric Resonator (CMDR) fed by a stepped microstrip monopole printed antenna, partial ground plane, and an I-shaped stub. The Crescent Moon dielectric resonator is placed on the microstrip monopole printed antenna to achieve wide impedance bandwidth, and the I-shaped stub is utilized to improve impedance bandwidth for the WiMAX band. A comprehensive parametric study is carried out using HFSS software to achieve the optimum antenna performance and optimize the bandwidth of the proposed antenna. The entire band is useful with two filtered bands at 5.5 GHz and 6.8 GHz by the creation of notches. The band’s rejection, WLAN band (5.2–5.7 GHz), and the downlink frequency band of ITU 7 GHz-band for satellite communication (6.5–7.3 GHz) is realized by inserting G-shaped and C-shaped slots in the ground. The simulation results demonstrate that the proposed CMDR antenna achieves satisfactory UWB performance, with an impedance bandwidth of around 88.7%, covers the frequency band of 3.2 - 8.3 GHz, excluding a rejection band for the WLAN and ITU 7 GHz band. The CMDR is simulated using HFSS and CST high-frequency simulators.

scholarly journals A Compact Slotted Patch Hybrid-Mode Antenna for Sub-6 GHz Communication

2020 ◽  
Vol 2020 ◽  
pp. 1-8
Author(s):  
Bei Huang ◽  
Mochao Li ◽  
Weifeng Lin ◽  
Jun Zhang ◽  
Gary Zhang ◽  
...  
Keyword(s):  
Frequency Band ◽  
Free Space ◽  
Operating Frequency ◽  
Impedance Bandwidth ◽  
Hybrid Mode ◽  
Average Gain ◽  
Operating Frequency Band ◽  
Rectangular Patch ◽  
Compact Size

A compact hybrid-mode antenna is proposed for sub-6 GHz communication. The proposed antenna is composed of a slotted rectangular patch, a feeding dipole, and a balun. Three modes are sequentially excited in a shared patch to achieve a compact size. A prototype antenna with a major size of 0.48 λ0 × 0.31 λ0 × 0.16 λ0 (λ0 is the wavelength in the free space at the center of the operating frequency band) is fabricated and measured. The measured results demonstrate an impedance bandwidth of 56.87% from 2.97 GHz to 5.33 GHz and an average gain of approximately 8.00 dBi with 1 dB variation in the operating frequency band of 3.0–5.0 GHz. The proposed antenna can be an element for microbase stations in sub-6 GHz communication.

scholarly journals A Dual-Band Base Station Antenna with a Split Ring for Sub-6 GHz Communication

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Bei Huang ◽  
Jie Cao ◽  
Weifeng Lin ◽  
Jun Zhang ◽  
Gary Zhang ◽  
...  
Keyword(s):  
Frequency Band ◽  
Free Space ◽  
Base Station ◽  
Dual Band ◽  
Operating Frequency ◽  
Impedance Bandwidth ◽  
Dual Polarization ◽  
Split Ring ◽  
Average Gain ◽  
Frequency Bands

A dual-band base station antenna is introduced in this paper. The proposed antenna is composed of baluns, bowtie patches, and a split ring. The two pairs of bowtie patches excited by the two orthogonal balun structures can achieve dual polarization. The split ring is used to yield two additional resonances to broaden the impedance bandwidth. In this way, a compact dual-band base station antenna is obtained with the size of 0.41 λc × 0.41 λc × 0.13 λc (λc is the wavelength in the free space at the lowest operating frequency band) and the average gain of 8.2 dBi. Moreover, the operating frequency bands of the proposed antenna cover 2515–2675 MHz, 3400–3600 MHz, and 4800–5000 MHz, which can function as an element for macro- or microcells in sub-6 GHz communications.

scholarly journals Wideband Circularly Polarized Dielectric Rod Antenna

2012 ◽  
Vol 2012 ◽  
pp. 1-4
Author(s):  
Min Guo ◽  
Ji-Jun Yan ◽  
Shun-Shi Zhong ◽  
Zhu Sun
Keyword(s):  
Circular Polarization ◽  
Frequency Band ◽  
Axial Ratio ◽  
Impedance Bandwidth ◽  
Central Frequency ◽  
Radiation Characteristics ◽  
Circularly Polarized ◽  
Feed Network ◽  
Measured Impedance ◽  
Better Than

A new dielectric rod antenna (DRA) is introduced to produce circular polarization (CP) over a wide frequency band without a complex feed network. Along with the simulated results, measured results of the antenna prototype are presented, showing a 3 dB axial ratio (AR) CP bandwidth of 17.7%. The radiation characteristics of the fabricated antenna are also demonstrated showing the measured gain of better than 6.2 dBi. Moreover, the measured impedance bandwidth (VSWR≤2) reaches 20.1%, from 8.75 GHz to 10.7 GHz, while the CP beamwidth (AR≤3 dB) at the central frequency is measured over 120°.

A Dual-Band LTCC Antenna with Cross Circuitous Structure

2012 ◽  
Vol 601 ◽  
pp. 163-167
Author(s):  
Hong Gang Hao ◽  
Wen Shuai Hu ◽  
Hai Yan Tian ◽  
Yi Ren
Keyword(s):  
Low Temperature ◽  
Frequency Band ◽  
Dual Band ◽  
Operating Frequency ◽  
Impedance Bandwidth ◽  
The Novel ◽  
Radiation Patterns ◽  
Directional Radiation ◽  
Dual Band Antenna ◽  
Layer Structures

A compact dual-band antenna for ISM (2.45GHz) or WiMAX (3.15GHz) applications by low-temperature co-fired ceramic (LTCC) technology is presented in this paper. The proposed antenna is composed of multi-layer structures to reduce the sizes effectively. The simulated results show that the dimensions of the antenna are 11×4.2×1.2mm3, with the 2:1 VSWR impedance bandwidth definition, the lower and upper band have the bandwidth of 80 and 90 MHz. The novel antenna has realized miniaturization and omni-directional radiation patterns across the whole operating frequency band.

scholarly journals An E-Band 21-dB Variable-Gain Amplifier with 0.5-V Supply in 40-nm CMOS

Electronics ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 804
Author(s):  
Gibeom Shin ◽  
Kyunghwan Kim ◽  
Kangseop Lee ◽  
Hyun-Hak Jeong ◽  
Ho-Jin Song
Keyword(s):  
Power Consumption ◽  
Frequency Band ◽  
Noise Figure ◽  
Complementary Metal Oxide Semiconductor ◽  
Oxide Semiconductor ◽  
Operating Frequency ◽  
Variable Gain Amplifier ◽  
Variable Gain ◽  
Operating Frequency Band ◽  
Shunt Capacitors

This paper presents a variable-gain amplifier (VGA) in the 68–78 GHz range. To reduce DC power consumption, the drain voltage was set to 0.5 V with competitive performance in the gain and the noise figure. High-Q shunt capacitors were employed at the gate terminal of the core transistors to move input matching points for easy matching with a compact transformer. The four stages amplifier fabricated in 40-nm bulk complementary metal oxide semiconductor (CMOS) showed a peak gain of 24.5 dB at 71.3 GHz and 3‑dB bandwidth of more than 10 GHz in 68–78 GHz range with approximately 4.8-mW power consumption per stage. Gate-bias control of the second stage in which feedback capacitances were neutralized with cross-coupled capacitors allowed us to vary the gain by around 21 dB in the operating frequency band. The noise figure was estimated to be better than 5.9 dB in the operating frequency band from the full electromagnetic (EM) simulation.

Compact dual and triple band antennas for 5G-IOT applications

2021 ◽  
pp. 1-8
Author(s):  
Ruchi ◽  
Amalendu Patnaik ◽  
M. V. Kartikeyan
Keyword(s):  
Microwave Frequency ◽  
Mobile Internet ◽  
Dual Band ◽  
Impedance Bandwidth ◽  
Printed Antenna ◽  
Iot Applications ◽  
Multiband Antennas ◽  
New Radio ◽  
Compact Size ◽  
Triple Band

Abstract Designing miniaturized multiband antennas to cover both the 5G new radio frequencies (FR1 and FR2) simultaneously is a challenge for wireless communication researchers. This paper presents two antenna designs : a dual-band printed antenna of size 18 × 16 × 0.285 mm3 operating at FR1–5.8 GHz and FR2–28 GHz and a triple-band printed antenna with dimensions 30 × 25 × 0.543 mm3 operating at FR1–3.5 GHz and 5.8 GHz (sub-6 GHz microwave frequency bands) and FR2–28 GHz (mm-wave frequency band). The final projected triple-band antenna has a compact size with an impedance bandwidth of 12.71%, 11.32%, and 18.3% at 3.5 GHz, 5.8 GHz, and 28 GHz, respectively with the corresponding gain of 1.86 dB, 2.55 dB, and 4.41 dB. The measured radiation characteristics of the fabricated prototypes show that the proposed designs are suitable for trendy 5G-RFID and mobile Internet of things (IoT) applications.

Artificial neural network-based seismic detector

1995 ◽  
Vol 85 (1) ◽  
pp. 308-319 ◽  
Author(s):  
Jin Wang ◽  
Ta-Liang Teng
Keyword(s):  
Neural Network ◽  
Artificial Neural Network ◽  
Input Data ◽  
Seismic Event ◽  
Signal To Noise Ratio ◽  
Type B ◽  
Earthquake Detection ◽  
Seismic Event Detection ◽  
Artificial Neural ◽  
Better Than

Abstract An artificial neural network-based pattern classification system is applied to seismic event detection. We have designed two types of Artificial Neural Detector (AND) for real-time earthquake detection. Type A artificial neural detector (AND-A) uses the recursive STA/LTA time series as input data, and type B (AND-B) uses moving window spectrograms as input data to detect earthquake signals. The two AND's are trained under supervised learning by using a set of seismic recordings, and then the trained AND's are applied to another set of recordings for testing. Results show that the accuracy of the artificial neural network-based seismic detectors is better than that of the conventional algorithms solely based on the STA/LTA threshold. This is especially true for signals with either low signal-to-noise ratio or spikelike noises.

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