In satellite remote sensing (SRS), there is a demand for large-power microwave components. A Butler matrix is essential to a transmitting antenna array in SRS. This article illustrates the electrical and mechanical design, simulation, and test result...
Butler Matrix networks are well established as beamforming networks for phased antenna arrays. The challenge we address in this work is to cover the entire (advanced 5G or 6G) FR3 band (7–24 GHz) with a single network, while retaining low losse...
In this paper, an intuitive approach to assessing advantages of beamforming in 5G wireless communication is proposed as a novel try and practical demonstration of importance of alignment between the transmitter’s and receiver’s beams working in milli...
Beam-switching technology is critical for fifth-generation (5G) Frequency Range 1 (FR1) base stations, yet existing odd-number Butler matrix designs often struggle to achieve compact size, low complexity, and efficient performance. Although a few stu...
A compact switched-beam array antenna, based on a switched Butler matrix with four folded ground antennas, is presented for unmanned aerial vehicle (UAV) applications. The folded ground structure, including a slotted patch radiator surrounded by mult...
This work presents a 28-GHz Butler matrix based switched-beam antenna for fifth-generation (5G) wireless applications. It integrates a 1 × 4 microstrip antenna, a 4 × 4 Butler matrix, and a single-pole four-throw (SP4T) absorptive switch in a single...
A compact and wideband beamforming antenna array based on a substrate-integrated coaxial line (SICL) Butler matrix at 60 GHz is proposed in this paper. The cavity-backed patch antenna loading double-ridged horn antenna is designed to enhance a gain o...
Massive Multiple-Input Multiple-Output (MIMO) systems with hundreds or thousands of antenna elements are fundamental to next-generation wireless networks, promising unprecedented spectral efficiency through spatial multiplexing and beamforming. Howev...
This work presents a Butler matrix based four-directional switched beamforming antenna system realized in a two-layer hybrid stackup substrate for 28-GHz mm-Wave 5G wireless applications. The hybrid stackup substrate is composed of two layers with di...
A low-loss, compact, ultra-thin, passive, 77 GHz, 8 × 8 microstrip Butler matrix on a 200 μm thick high-purity fused-silica (HPFS) glass substrate embedded in 0.8 μm thick patterned gold conducting layers was developed for low power autom...
This paper presents a four-phase beam-steering antenna for 28 GHz wireless communication, targeting the demand for high-efficiency and low-complexity beam-steering solutions in millimeter-wave systems. The proposed design employs a Butler matrix netw...
A novel concept of four-beam antenna arrays operating in a one-octave frequency range that allows stable beam directions and beamwidths to be achieved is proposed. As shown, such radiation patterns can be obtained when radiating elements are appropri...
A beam-steerable dual-circularly polarized 60 GHz antenna array is proposed. A 1 × 4 dual-fed stacked patch antenna array is integrated with an 8 × 8 Butler matrix. By utilizing the 8 × 8 Butler matrix, the proposed antenna array ge...
A millimeter-wave multi-layer and miniaturized multibeam antenna fed by an E-plane Butler matrix (BM) in substrate integrated waveguide (SIW) technology is proposed. For the beam-forming network (BFN), a folded E-plane 4 × 4 BM is proposed, who...
Fifth generation (5G) technology aims to provide high peak data rates, increased bandwidth, and supports a 1 millisecond roundtrip latency at millimeter wave (mmWave). However, higher frequency bands in mmWave comes with challenges including poor pro...
A small zero-order resonant antenna based on the composite right-left-handed (CRLH) principle is designed and fabricated without metallic vias at 30 GHz to have patch-like radiation. The mirror images of two CRLH structures are connected to design th...
Design of Butler matrices dedicated to Internet of Things and 5th generation (5G) mobile systems—where small size and high performance are of primary concern—is a challenging task that often exceeds capabilities of conventional techniques...
The single antenna used in conventional ultra-wideband radar has difficulty tracking targets over a wide range because of a relatively narrow beamwidth. Herein, we propose a beamforming antenna that can track targets over a wide range by electronical...
This paper provides a comprehensive review of recent advancements in radio-frequency (RF) multifunctional components with integrated filtering characteristics, including tunable filtering attenuators, filtering power dividers, filtering couplers, and...
In Microwave Monolithic Integrated Circuits, crossovers maintain signal purity when transmission lines overlap with each other. A simple crossover for dual band applications, particularly suitable for the development of smart antennas, is presented i...
This paper presents a novel compact 4 × 4 Butler matrix (BM) employing a quasi-twisted branch line coupler (QBLC) as the unit cell to achieve enhanced bandwidth performance. The proposed BM integrates four QBLCs, a uniquely designed 0 dB crosso...
Phased antenna arrays have revolutionized modern wireless systems by enabling dynamic beamforming, multibeam synthesis, and user tracking to enhance data rates and reduce interferences, yet their reliance on expensive active components (e.g., phase s...
This paper presents a multibeam hybrid beamforming (MHBF) architecture for microwave power transfer (MPT), enabling wireless power delivery to multiple receivers with a reduced number of RF chains. The proposed architecture decouples beam control int...
This paper describes the design of a hybrid coupler with a continuously variable output phase difference. This is achieved by using reconfigurable transmission lines with electrically tunable lengths controlled by two biasing voltages through varacto...
The underground mining industry faces significant challenges in maintaining reliable communication due to multipath fading and physical obstructions, leading to weak signals and dead spots. This study addresses these issues by proposing a smart anten...
Novel three-dimensional discrete lens antennas characterized by a number of focal points ranging from one to five and defined explicitly via analytical equations are presented in the paper. A procedure to derive rotationally symmetric afocal lenses s...
This article presents a 4-way 2-D butler matrix (BM)-based beamforming network (BFN) using a multilayer substrate broadside coupled stripline (BCS). To achieve the characteristics of a compact, wide-bandwidth, high-gain phased array, a BCS coupler is...
A complete end-to-end far-field wireless power transfer (WPT) is proposed and studied in this paper for the application of the Internet of Things (IoT) at the industrial, scientific, and medical (ISM) band of 2.4 GHz. The radiative WPT has achieved a...
This paper presents a novel switchable branch-line coupler (BLC) designed to achieve variable phase shifts while maintaining a constant output power. The proposed design incorporates low stepwise phase shifters with incremental phase shifts of 10°...
A novel quasi-twisted miniaturized wideband branch line coupler (BLC) is proposed. The design is based on bisecting the conventional microstrip line BLC transversely and folding bisected sections on double-layered substrates with a common ground plan...