Search

A high-isolation wideband MIMO (Multiple-Input Multiple-Output) antenna, shaped like a palm tree, is designed for 5G wireless communication purposes. The propounded MIMO antenna is formulated on an FR4 substrate, featuring a quartet of ports and adhering to a precise dimension of 45 × 50 × 0.8 mm3. A detailed analysis of the proposed high isolation wideband palm tree shaped MIMO antenna, considering its bandwidth, gain, isolation, radiation patterns, and diversity performance metrics such as diversity gain, channel capacity loss, mean effective gain, and total active reflection coefficient, is presented. The results obtained from simulations and measurements demonstrate good agreement, indicating the antenna's effectiveness for intended applications. Indeed, an extensive bandwidth covering a range of 11.6 GHz from 23.4 GHz to 35 GHz is achieved by demonstrating superb reflection coefficient. Additionally, the design reports remarkable isolation and a peak gain of 12.4 dB, indicating its ability to enhance signal strength. One of the most notable features of this MIMO antenna is its coverage of multiple 5G bands, making it ideal for use in various geographical regions, including the USA and Canada (27.5–28.35 GHz, 37.0–37.6 GHz, and 37.6–40.0 GHz), China (24.75–27.5 GHz), Korea (28–39 GHz), Japan (27–29.5 GHz) and Sweden (26 GHz). [ABSTRACT FROM AUTHOR]

In this work, the automated design of a power amplifier circuit in a 130 nm BiCMOS technology operating in the 220 GHz to 260 GHz frequency range is presented. The design automation process is based on the RapidIP approach, which enables the evaluation, rating and optimisation of thousands of different circuit topologies within only a few minutes. In total 6. 13 ⋅ 1 0 5 optimisation steps and 2. 6 ⋅ 1 0 4 different circuit topologies have been explored within an overall runtime of 23 min. According to post-layout simulations, the amplifier achieves a saturated output power of 9 dBm with a peak power-added efficiency of 2.8% and a 3 dB-bandwidth of 55 GHz. [ABSTRACT FROM AUTHOR]

This paper presents a high-gain and ultra-wideband antipodal Vivaldi antenna (AVA) with vias-loaded linearized edges for 5G millimeter-wave applications. By replacing the traditional exponential tapered edge by linear tapered slot (LTS), the side-lobe is obviously descended. Moreover, metal vias are loaded on radiation edges, more energy in the main radiation direction is constrained and the antenna directivity and gain performance are improved. A prototype of the proposed antenna was designed, fabricated and measured. The measurements agree well with the simulations, which certify the new way for miniaturization and easier fabrication of the propose antenna. The measured results show that the antenna achieves a peak gain up to 12.1 dBi at 36 GHz and gain of 10.8 ± 1.3 dBi in the operating range from 22 to 40 GHz, where the reflection coefficient is less than −10 dB. The gain increment is up to 2 dB compared with the conventional AVA. Due to characteristics like high-gain, ultra-wideband, and compact size, it is highly well-suited for 5G millimeter-wave applications. [ABSTRACT FROM AUTHOR]

A two element multiband multiple-input multiple-output (MIMO) antenna system with low specific absorption rate is proposed for Ka-band space satellite, millimeter-wave (mm-wave), fifth-generation (5G), and future sixth-generation (6G) wireless communication applications. The essential characteristics of both 5G and future 6G communications can be fulfilled by the proposed MIMO antenna design. The proposed MIMO antenna system has significant advantage of covering four relevant and usable frequency bands, i.e., 16 GHz, 25.5 GHz, 28 GHz, and 32 GHz used for the above mentioned applications. The design of the presented antenna looks like a vertical Yagi-Uda antenna with L-shaped ladder. Moreover, two circular slots and a slotted vertical stub are etched in a partially shared ground. The complete electrical dimension of the presented antenna is 6.8 λ 0 × 5. 7 λ 0 × 0. 068 λ 0 , calculated at resonating frequency 25.5 GHz, where λ 0 is wavelength in free space. The geometry of the presented antenna is fabricated using Rogers RO4350TM with dielectric constant (ϵ r) of 3.48, a loss tangent of 0.0025, and the substrate thickness of 0.8 mm. The presented MIMO antenna is excited with a 3 mm wide microstrip feed line having 50 Ω characteristics matched impedance. In terms of performance, the proposed antenna has achieved a reflection coefficient < - 10 dB, and isolation < -15 dB in all the resonating bands, radiation efficiency varies 72%–84%, impedance bandwidth of 4.6 GHz, 1.5 GHz, 1.11 GHz, and 7.5 GHz, and realized gain of 10.18, 12.05, 13.07, & 5.55 dBi is also achieved at frequencies 16 GHz, 25.5 GHz, 28 GHz, and 32 GHz. The achieved values for various MIMO matrices are envelope correlation coefficient > 0.0048, diversity gain of 9.98 dB, channel capacity loss < 0.00023 bits/s/Hz, and mean effective gain < -6 dB. The simulated results obtained by ANSYS I 2022 R2 (HFSS) and the experimental results measured by vector network analyzer (VNA) show a good agreement. [ABSTRACT FROM AUTHOR]

Abstract A comprehensive design methodology for microstrip broadband attenuators is presented. Closed-form design equations are given for two types of distributed attenuators. The attenuators are based on a cascade connection of thin-film resistors and microstrip line sections. The structure provides maximally flat attenuation and wideband performance without the need of plated via holes to ground, facilitating manufacture as well as achieving proper performance at millimeter wave frequencies. Experimental results demonstrate the validity of the technique applied to 3 dB and 13 dB broadband attenuators on alumina substrate up to 67 GHz. The proposed topology can be applied not only to MIC, but also to MMIC designs at the highest frequencies. [ABSTRACT FROM AUTHOR]

In this paper, a low insertion loss (IL) wideband millimeter wave (mm-Wave) crossover with three-section branch-line structure based on ridge gap waveguide (RGW) technology is proposed. Firstly, the central-crossover is designed, especially two types of tuning pins are introduced, which greatly improves the performance of the crossover. In addition, in order to facilitate the measurement, the transition from rectangular waveguide (RWG) to RGW is designed. Finally, a prototype is manufactured and measured. The simulation results show that in the frequency range of 28.9 GHz to 36.6 GHz, RL is better than 20 dB, while the isolation levels of | S 21 |, | S 41 |, and | S 43 | are lower than −20 dB, −10 dB, and −20 dB over the same band, respectively. IL is below 0.5 dB in the frequency range of 28.15 GHz to 36.65 GHz. Good consistency was observed between the simulation results and the measurement results. [ABSTRACT FROM AUTHOR]

In this paper, a low-profile, compact, high-gain antenna solution for four-port mm-wave broadband MIMO communication in a 5G environment is presented. The proposed antenna design consists of two rectangular patches connected through a corporate feed network and two quarter-wavelength square-shaped CSRRs on the ground plane. The overall size of the proposed four-port orthogonal MIMO configuration is 28.3 mm × 28.3 mm × 0.508 mm. The antenna operates on the 5G frequency bands of n257, n258, and n261 with an effective bandwidth of 3.9 GHz covering the range of 26.5 GHz to 30.4 GHz. The suggested MIMO antenna attained a peak gain of 11 dBi and radiation efficiency of 96% at 28 GHz resonating frequency. The MIMO configuration utilized DGS to minimize near-field coupling current at the ground plane, resulting in high port-to-port isolation of > 40 dB, and co-pol to X-pol isolation improvements of > 9 dB and > 19 dB in the boresight direction of E-plane and H-plane at 28 GHz resonating frequency. The antenna's superior diversity performance is supported by several performance metrics, including ECC(< 0.0001), DG(> 9.999 dB), CCL(< 0.12 bits/s/Hz), MEG (< −3 dB), and TARC. Moreover, the linear transmission property of the proposed MIMO antenna is also validated through the variation of group delay (< 0.6 ns) over operating frequency bands in the far-field region. [ABSTRACT FROM AUTHOR]

This paper presents a wideband millimeter wave (mm-Wave) high-gain multibeam antenna array fed by Butler Matrix (BM) based on groove gap waveguide (GGW) technology. First, the components of 4 × 4 GGW BM have been designed and analyzed, especially the proposed modified crossover, which greatly improves the performance of BM as feeding network. Then a 2 × 2-element subarray with three layers has been proposed, combined with the 4 × 4 GGW BM to form a 1 × 4 broadside antenna array. Finally, the prototype of high-gain wideband four-beam antenna array has been manufactured and measured. The measured results verify the superior performance of the multibeam antenna array between 26.3-29.7 GHz. The return loss (RL) can reach 15 dB and isolation between ports is also less than 15 dB, and the measured maximum gain of radiation patterns and the maximum radiation efficiency can also reach 19.05 dBi and 86.8%, respectively. The measured results have a good agreement with the simulated results. [ABSTRACT FROM AUTHOR]

A new 4-port dual-band printed Multi-Input Multi-Output (MIMO) antenna array operating at 28 GHz and 38GHzin the mm-wave band for 5G communications is proposed in this paper. The designed MIMO antenna array consists of 4 MIMO elements structured with 8 identical patches arranged in 2 × 4 configuration and a cross-shaped defected ground plane on a physical footprint of 43.611 × 43.611 × 0.4 m m 3 Rogers RT/duroid 5880 substrate. In order to obtain the desired dual-band operation with good impedance matching, enhanced gain and bandwidth, the patch elements are designed by incorporating combinations of circular and semi-circular shaped slots, and the cross-shaped ground plane is modified with an extended circular-shaped defect. The suggested MIMO configuration offers a high gain of about 7.9 and 13.7 dB at 28 and 37.3 GHz, respectively. Furthermore, the MIMO performance metrics of the proposed design are analyzed and presented. The prototype of the designed MIMO antenna has been fabricated and measured to validate the simulation results. The simulation and measurement results show good agreement. The proposed MIMO antenna covers 28 GHz (27.50–28.35 GHz) and 37 GHz (37–37.6 GHz) 5G bands to be deployed in the USA and Canada. [ABSTRACT FROM AUTHOR]

A new 4-port dual-band printed Multi-Input Multi-Output (MIMO) antenna array operating at 28 GHz and 38GHzin the mm-wave band for 5G communications is proposed in this paper. The designed MIMO antenna array consists of 4 MIMO elements structured with 8 identical patches arranged in 2 × 4 configuration and a cross-shaped defected ground plane on a physical footprint of 43.611 × 43.611 × 0.4 m m 3 Rogers RT/duroid 5880 substrate. In order to obtain the desired dual-band operation with good impedance matching, enhanced gain and bandwidth, the patch elements are designed by incorporating combinations of circular and semi-circular shaped slots, and the cross-shaped ground plane is modified with an extended circular-shaped defect. The suggested MIMO configuration offers a high gain of about 7.9 and 13.7 dB at 28 and 37.3 GHz, respectively. Furthermore, the MIMO performance metrics of the proposed design are analyzed and presented. The prototype of the designed MIMO antenna has been fabricated and measured to validate the simulation results. The simulation and measurement results show good agreement. The proposed MIMO antenna covers 28 GHz (27.50–28.35 GHz) and 37 GHz (37–37.6 GHz) 5G bands to be deployed in the USA and Canada. [ABSTRACT FROM AUTHOR]

In this paper, we present an extreme learning machine (ELM) neural network designed to perform multiple-input multiple-output (MIMO) detection for millimeter-wave (mm-wave) communications operating in the 28 GHz frequency band. The ELM strategy can perform online MIMO combining processing. This method does not require offline training like with deep neural networks. The proposed technique was compared in terms of the achievable bit error rate (BER) and spectral efficiency (SE) to the maximum ratio (MR) and minimum mean squared error (MMSE) MIMO detectors, considering an orthogonal frequency-division multiplexing (OFDM) uplink scheme based on the fifth generation (5G) New Radio standard. Numerical results show that the ELM strategy outperforms the MR and MMSE detectors since this method reduces the inter-user interference effects, specifically for low equivalent isotropic radiated power at the receiver during the uplink communication. Furthermore, the ELM method requires only 16 % of the floating-point operations required by the MMSE detector. [ABSTRACT FROM AUTHOR]

A rectangular dielectric resonator based connected ground quad-elements MIMO antenna fed using substrate integrated waveguide (SIW) is proposed for millimeter-wave 5G application. SIW in TM 10 mode was used to excite multiple modes in the dielectric resonator to achieve multiple resonance. An individual element of the proposed MIMO antenna is arranged in a cross shaped structure to achieve polarization and spatial diversity. The proposed MIMO system operates at dual operating frequency bands having impedance bandwidth of 24% (24.50–27.50 GHz) and 12% (33–37 GHz). The isolation better than 22 dB and 17 dB is achieved throughout the proposed bands without using any additional isolation techniques. The proposed MIMO antenna has a peak gain of 9.9 dB and minimum radiation efficiency of 96%. It radiates in a broadside direction with acceptable MIMO diversity results where envelope correlation coefficient is below 0.15, channel capacity loss is below 0.6 bits/sec/Hz, diversity gain of 9.98 dB, and total active reflection coefficient below −10 dB over the desired band of operation. The prototype of the quad-elements SIW fed DRA MIMO was manufactured after which the antenna and diversity performance parameters were measured and satisfactory correlation is observed. [ABSTRACT FROM AUTHOR]