Microstrip Line Feed Network Research Articles

A Broadband High-Gain Printed Antenna Array Using Dipole and Loop Patches for 5G Communication Systems

A broadband and high-gain printed antenna array is presented in this paper. Its single antenna element consists of a loop and two symmetric dipole patches, making the element exhibiting broad impedance bandwidth and improved gain at the targeted frequency, which is 28 GHz, one of the 5G mm-wave band, for this design. An 8×3 antenna array fed by a microstrip line feed network was designed and simulated. With a compact size of 98×32.5 mm2 , the array presents a broad -10 dB impedance bandwidth of 6.8 GHz (24.3%) and a high gain of 18 dBi at 28 GHz. Besides, the single-layered array also features low profile, simple geometry, and low cost, making it a good candidate for 5G communication systems.

A High-Gain Millimeter-Wave Magnetoelectric Dipole Array With Packaged Microstrip Line Feed Network

A millimeter-wave 4 × 4 magnetoelectric (ME) dipole antenna array using a packaged microstrip line feed network is proposed. This antenna array features a wide impedance bandwidth of more than 50% and small back radiation. Each ME dipole element is excited by an L -shaped probe and each L -shaped probe is connected to the packaged microstrip line through a small hole in the ground plane. The packaged microstrip line forms the whole corporate feed network for the antenna array. The entire antenna structure is realized by multiple printed circuit boards (PCBs), which is low in material cost and easy in fabrication. The results demonstrate that the proposed antenna array enables the impedance bandwidth of 51.5%, high gain up to 20.3 dBi, and stable broadside radiation pattern with small back radiation over the operating frequencies. The array is suitable for the 5G application.

Metasurfaces for Reconfiguration of Multi-Polarization Antennas and Van Atta Reflector Arrays

This paper discusses the application of metasurfaces for three different classes of antennas: reconfiguration of surface-wave antenna arrays, realization of high-gain polarization-reconfigurable leaky-wave antennas (LWAs), and performance enhancement of van Atta retrodirective reflectors. The proposed surface-wave antenna is designed by embedding four square ring elements within a metasurface, which improves matching and enhances the gain when compared to conventional square-ring arrays. The design for linear polarization comprises of a 1 × 4 arrangement of ring elements, with a 0.56λ spacing, placed amidst periodic patches. A 2 × 2 arrangement of ring elements is utilized for reconfiguration from linear to circular polarization, where a similar peak gain with better port isolation is realized. A prototype of the 2 × 2 array is fabricated and measured; a good agreement is observed between simulations and measurements. In addition, the concepts of the design of polarization-diverse holographic metasurface LWAs that form a pencil beam in the desired direction with a reconfigurable polarization are discussed. Moreover, recent developments incorporating polarization-reconfigurability in metasurface LWAs are briefly reviewed. In the end, the theory of van Atta arrays is outlined and their monostatic RCS is reviewed. A conventional retrodirective array is designed using aperture-coupled patch antennas with a microstrip-line feeding network, where the scattering from the structure itself degrades the performance of the reflector. This is followed by the integration of judiciously synthesized metasurfaces to reconfigure and improve the performance of retrodirective reflectarrays by removing the above-mentioned undesired scattering from the structure.

Packaged Microstrip Line Feed Network on a Single Surface for Dual-Polarized 2N×2M ME-Dipole Antenna Array

A packaged microstrip line feed network on a single substrate surface is presented in the Ka-band for a 4 × 4 dual-polarized array with a capability to be expanded to higher order 2N × 2M, where N and M are integer numbers larger than 1. A dual-polarized aperture-coupled magneto-electric dipole antenna is designed as a single element with 20% bandwidth of −10 dB reflection coefficients, ports’ isolation better than 35 dB, cross polarization less than −25 dB within the main beam view-range of 30°, and gain of 8 dBi. A 4 × 4 array is implemented that maintains a bandwidth of 16.7% at 30 GHz with a maximum gain of 19.3 dBi.

Millimeter-Wave Beam-Steering Focal Plane Arrays With Microfluidically Switched Feed Networks

Microfluidically switched feed networks are introduced to realize millimeter-wave beam-steering focal plane arrays (FPAs). Switching functionality is achieved by a selectively metallized plate (SMP) repositionable within a microfluidic channel that is brought in close proximity to the microstrip line feed network of an FPA. The feed network is strategically designed to exhibit gap discontinuities that are sequentially overlapped by the SMP metallizations. The capacitive couplings between the SMP metallizations and the gap discontinuities are designed to achieve wideband (~20 GHz) switching functionality with low insertion loss (IL $10\times $ lower than that of the prior work. This allows to achieve a faster beam-steering speed (0.27 s versus 5.25 s of previous designs). An integrated sensing approach for detecting the SMP position is also presented for the first time to facilitate the use of presented MFPAs with closed-loop position control.

Multiple Fan-Beam Antenna Array for Massive MIMO Applications

In this paper, a multiple fan-beam antenna array is proposed for massive multiple-input multipleoutput (MIMO) applications. The proposed array is based on vertical spatial filtering to reduce radio frequency complexity in a massive MIMO system. A microstrip line feeding network is utilized to achieve a specific phase distribution for multiple fan beams. A 64-element antenna array is designed and fabricated to validate the design strategy. The proposed antenna array uses 16 ports to excite 64 antenna elements, which is more cost effective than traditional massive MIMO systems. The measured results demonstrate that the proposed antenna array can achieve two fan beams at 7 in the vertical dimension, and the measured gain of every port exceeds 10 dBi at 2.6 GHz.

A Dual-Beam Eight-Element Antenna Array With Compact CPWG Crossover Structure

In this letter, a dual-beam eight-element antenna array is proposed with compact coplanar waveguide with ground (CPWG) crossover structure. The feeding network is composed of a microstrip-line feeding network with four 90° hybrids and a CPWG feeding network with compact crossover structures. Compared to the conventional Butler matrix feeding network, the proposed network has fewer 90° hybrids and circuit is less complex. By exciting different port of the feeding network, the eight-element antenna can be excited by phase step of 22.5° or –22.5° and achieve two beams pointing at two different directions. The measured gain is 10.2 dBi, and beam directions of the two peaks are ±7° at 5.8 GHz.

Microfluidically Reconfigured Wideband Frequency-Tunable Liquid-Metal Monopole Antenna

A microfluidically reconfigured wideband frequency-tunable liquid-metal monopole antenna is presented. The antenna operation relies on continuous moving of the liquid-metal volume over the capacitively coupled microstrip line feed network with a micropump unit. To maximize the capacitive coupling at the feed point, the antenna is realized by bonding microfluidic channel molds prepared in polydimethylsiloxane (PDMS) polymer with 1-mil-thick liquid crystal polymer (LCP) substrate. The concept is demonstrated through the design and experimentation of a 4:1 frequency-tunable monopole antenna that operates from 1.29 to 5.17 GHz. The presented monopole antenna can also be utilized as an element to form wideband frequency-tunable high-gain antenna apertures without necessitating any additional micropump units. This is accomplished by resorting to strategically meandered or interconnected microfluidic channels. This concept is demonstrated through the design and experimentation of a $4 \times 1$ microfluidically controlled monopole array capable of providing 2:1 frequency tuning range from 2.5 to 5 GHz.

Wideband ring-slot coupled patch antenna with enhanced gain

A wideband ring-slot coupled patch antenna is presented in this paper. A microstrip line feeding network is used for impedance matching. Additionally, in order to depress the backward radiation caused by the resonance of the ring-slot, a reflector is introduced to obtain unidirectional radiation patterns, while a dielectric cover is adopted to alleviate the deterioration in impedance caused by the reflector. A prototype is fabricated and measured. The measured results are in good agreement with those simulated, which indicates that the antenna operates well with a relative bandwidth of 55% for reflection coefficient less than −10 dB, an enhanced gain of 8–11 dBi, unidirectional radiation patterns, as well as low cross-polarization.

Design and Development of a 2 × 1 Array of Slotted Microstrip Line Fed Shorted Patch Antenna for DCS Mobile Communication System

Compact microstrip antennas have recently received much attention due to the increasing demand of small antennas for personal communication equipment. The problem of achieving a wide impedance bandwidth for compact microstrip antennas is becoming an important topic in microstrip antenna design. In this paper the design and development of a 2 × 1 array of a low cost slotted microstrip line fed shorted patch antenna (MFSPA) has been presented. Both the shorted patch and microstrip line feed network have air substrate. The material cost is thus reduced to a minimum. The array consists of two adjacent patches fed, using a simple microstrip T network. The impedance bandwidth of nearly 40%, covering the bandwidth requirement of 1750 MHz band is obtained. Also the antenna exhibits dual band operation. The cross polarization radiation in H-Plane observed with a single element antenna has been reduced considerably with 2 × 1 array. A peak antenna gain of 9.2 dBi is obtained with a small variation of 0.8 dBi. From the results obtained it is clear that the antenna array studied has a low cost fabrication and is suitable for applications in DCS mobile communication base station.

New simple feed network for an array module of four microstrip elements

A simple microstripline feed network for an array module comprising four microstrip elements is described. The advantages and disadvantages of the network are discussed as well as a theoretical explanation for the radiation characteristics of array modules using the network.