In this letter, a compact beamsteering multiple-input-multiple-output (MIMO) antenna is proposed for directional modulation applications. A generalization of the principle presented and by exploiting antenna's unidirectional capability within entire azimuth plane, system realizes secure steerable transmissions in direction legitimate receiver, with low bit error rate <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math...

This letter proposes a compact and energy-efficient directional modulation scheme for small power constrained devices (e.g., Internet of Things wireless sensors). The uses uniform circular array monopole antennas, with single radiofrequency chain antenna active at time. antennas can be located in close proximity, offering significant size reduction. Furthermore, the was demonstrated to operate successfully an 0.6 λ diameter. system does not generate additional artificial noise, limiting...

This tutorial discusses the problem of angle arrival (AoA) estimation from small Internet Things devices. It reviews limitations and challenges existing miniaturization strategies, which involve classical antenna arrays. As larger distance between antennas is typically needed for increased precision, without loss accuracy a significant problem. The article demonstrates that use electrically does not directly solve problem, since smaller may require to avoid coupling elements. Therefore, this...

In this article, a compact 3D beam-steering MIMO antenna operating at 5.75 GHz is proposed for on-body Internet of Things (IoT) applications.The planar comprises central patch and two concentric annular rings.The theory spherical modes used to discuss the concept, where free space measured beam-scanning covers entire xy-plane, while 44 • range realized in xz yz-planes.The performance tested using multi-layer phantom, peak gain 6.41 dBi.The characterized by size (0.77λ), low profile (0.03λ),...

This work proposes compact multimode Multiple-Input–Multiple-Output (MIMO) antennas for Angle of Arrival (AoA) estimation in miniaturized Internet Things (IoT) systems. The method excites different orthogonal radiating modes (TM <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$_{21}$</tex-math></inline-formula> , TM notation="LaTeX">$_{02}$</tex-math></inline-formula> and...

In this letter, a novel design of circularly polarized dielectric image line (DIL) based periodic leaky-wave antenna (P-LWA) is presented, which comprised only radiation discontinuities, side gratings, and inclined slots. The unit cell the proposed first optimized with full-wave eigenmode simulator for center frequency 79 GHz. Later, total 10 cells are cascaded to form DIL P-LWA, connected an in-plane transition feed from standard WR12 waveguide. Full-wave simulation experimental results...

This work proposes compact multiport antennas for directional modulation (DM) on wrist-wearable devices to improve the secrecy and privacy of transmitted data. The DM performance is investigated using antenna in free-space with a human forearm-phantom. system achieves low Bit Error Rate (BER) < 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−1</sup> 44° beamwidth, unique steerable secure direction over entire azimuth plane. Full-wave...

This work proposes a small pattern and polarization diversity multi-sector annular antenna with electrical size profile of <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ka</i> = 1.2 0.018λ, respectively. The is planar comprises sectors that are fed using different ports to enable digital beamforming techniques, efficiency gain up 78% 4.62 dBi, cavity mode analysis used describe the design concept diversity. proposed method can produce...

The paper presents a compact multiport antenna, with beamforming capabilities and realized gain of 4.31 dBi the size λ/2. antenna allows digital independent control over three parameters: main-beam direction, beamwidth, null-depth. Those parameters can be dynamically adjusted within continuous range, create multiple beams for different frequency channels, simultaneously generate patterns. Due to capabilities, proposed offers much greater flexibility switch-based analogue Electronically...

A low-profile Electrically Small Antenna (ESA) capable of pattern and polarization diversity is presented in this paper. The cavity model analysis used to describe the antenna design concept, where a step-by-step surface current distribution-based approach applied discuss characteristics. Rectangular V-like shaped slits are for isolation enhancement miniaturization, respectively. It demonstrated that can generate multiple patterns enable good coverage across elevation plane, with linear...

Recent advancements in the field of Internet Things (IoT) have turned this area one most promising research topics to bring innovative and useful technologies future.Solutions for a low-cost efficient Home Automation model always been widely addressed problem; This study focuses on architecture design wireless, flexible inexpensive smart home system.Using Mega 2560 Arduino Board Platform, we develop an intelligent system able send real-time video GSM-based information break-in, fire motion...

This work proposes an energy-efficient Directional Modulation (DM) scheme for on-body Internet of Things (IoT) devices. DM performance is tested using a 5-port stacked-patch MIMO antenna under two scenarios: free space case and four-layer human forearm phantom to simulate the user's wrist. It demonstrated that achieves steerable secure transmissions across entire horizontal plane. With low Bit Error Rate (BER) 1.5 × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML"...

&lt;p&gt;This article studies security aspects of data transmission in on-body Internet Things (IoT) devices through the use Directional Modulation (DM) from a smart watch integrated antenna. DM is beamsteering-based Physical Layer Security (PLS) method used to transmit baseband constellations known secure locations, while simultaneously scrambling them other directions. However, state-of-the-art implemented using large arrays, which are out-sized for many IoT devices. To overcome this...

his article studies the security aspects of data transmission in on-body Internet Things (IoT) devices through use Directional Modulation (DM) from a smartwatch integrated antenna.DM is beam steering-based Physical Layer Security (PLS) method used to transmit baseband constellations known secure locations while simultaneously scrambling them other directions.However, state art, DM implemented using large arrays, which are outsized for many IoT devices.To overcome this challenge, study...

Phased antenna arrays are commonly used to determine the Angle-of-Arrival (AoA) of radio signals. However, in cases where limitations on size and weight a concern, fresh approach involves using an innovative spherical mode-driven setup with Multiple-Input Multiple-Output (MIMO) antennas. These new antennas offer unprecedented reduction size. when traditional AoA estimation techniques applied multiport nonlinear spatial configuration, nuances algorithm's behavior merit exploration. This paper...

A technique to enhance the bandwidth characteristics of spherical modes-based beamsteering antennas is investigated in this work. The solution comprises a top-loaded monopole, shorted ring antenna, and metasurface layer used for enhancement. It demonstrated that proposed antenna can scan continuously across entire azimuthal plane. operates at center frequency 4.42 GHz where size with respect wavelength 0.73λ × 0.18λ. overlapping -10 dB impedance covers 265 MHz, total efficiency stays above...

This paper proposes a compact stacked-patch multiple-input multiple-output (MIMO) antenna with beam-steering in azimuth and elevation planes. The beamsteering is executed by controlling phase shifts amplitudes between the antenna's six ports. Full-wave simulated results are presented for 2.4 GHz. isolation ports better than 16.5 dB realized gains up to 6.71 dBi. provides 360° unidirectional plane scanning range of 120° demonstrated plane.

This work proposes a compact stacked-patch antenna capable of beamsteering in the vertical and horizontal directions. These characteristics are studied to realize directional modulation (DM) schemes planes, using structure 0.56λ diameter. The design offers unidirectional across entire xy-plane, with scanning range 118° 112° xz yz-planes, respectively. A peak realized gain 6.75 dBi is achieved, an isolation better than 15 dB at center frequency 2.4 GHz. performance shows beamwidth Bit Error...

The paper proposes a technique for sensing of moisture content waste block based on Wheeler Cap measurement method. allows sufficient penetration into the sample due to relatively low frequencies in VHF band. Water blocks within can be detected increased loss compared dry sample. simulation setup comprises cylindrical structure and an electrically small antenna which is located same enclosure as Material Under Test (MUT). frequency shift amplitude change reflected signal. study demonstrates...

This work proposes compact, flexible Multiple Input Output (MIMO) antennas. The design principle is based on the excitation of different orthogonal radiating modes within same antenna volume. Via phase control excited modes, beamforming demonstrated in azimuth and elevation planes using single-layered structures. For flexibility, antennas are designed Polydimethylsiloxane (PDMS) as substrate. Numerical results demonstrate that isolation better than 23 dB realized all investigated under bend...