A superheterodyne transmission scheme is adopted and analyzed in a 300 GHz wireless point-to-point link. This was realized using two different intermediate frequency (IF) systems. The first uses fast digital synthesis which provides an IF signal centered around a carrier frequency of 10 GHz. The second involves the usage of commercially available mixers, which work as direct up- and down-converter

This paper presents a novel GaN-based digital outphasing power amplifier (PA) for the 800 MHz range. The PA reaches a maximum output power of 5.8 W at 30 V final-stage (FS) drain supply voltage. A novel output combiner circuit is used and efficiency is improved by resonant commutation of the FSs and optimized driver circuits for the two GaN push-pull FSs. 3D electromagnetic simulation of output ne

A growing interest in dielectric waveguides (DWGs) as an alternative to commonly used waveguides (like coaxial or twisted-pair cables) for high data rate interconnects could be observed in the last few years. Especially in the mm-wave frequency range (30?300 GHz) applications with these waveguides benefit from low losses and low dispersion. Moreover, using both polarizations of the fundamental mod

The implementation of advanced multi-level modulation schemes such as quadrature phase-shift keying (QPSK) in contrast to the conventional on?off keying is crucial to further boost the terahertz (THz) communications speed. Thereby, carrier phase noise reduction in the THz range is one of the key goals that need to be urgently achieved. In this paper, the photonic-based THz sources and the phase no

In this paper, a new design of an optoelectronic system for transient waveforms shaping, with a selection of rejected frequencies, is presented. The generation of short pulses is performed with several optoelectronic generators using photoconductive semiconductor switches (PCSS) operating in linear switching mode and triggered via a laser pulse. With the appropriate number of generators, the syste

In this paper, an antenna-to-antenna method to design high-efficiency polarization converters was proposed. Two in-linked split ring resonators (SRRs) were used as the fundamental unit cell, which can effectively make the original linear polarization angle deflected into a customized one (include but not limited to 90°). The same as the process of energy reception and transmitting of microstrip sy

In this paper, a high gain wideband circularly polarized (CP) microstrip antenna is presented for broadband operation. The proposed structure comprised of a partially grounded printed monopole antenna loaded with a split ring resonator and a metallic reflector. By using the metallic reflector surface underneath the patch radiator results in the reflected waves in the same phase with main lobe radi

In this work, we proposed an adaptive beamformer based on a novel heuristic optimization algorithm. The novel optimization technique inspired from Fibonacci sequence principle, designated as Fibonacci branch search (FBS), used new tree's branches fundamental structure and interactive searching rules to obtain the global optimal solution in the search space. The branch structure of FBS is selected

This paper presents a novel dual-band (DB) dual-polarized (DP) shared aperture antenna with high isolation by using a combination of microstrip dipoles and dielectric resonator antennas (DRAs) for S and C bands, respectively. In the S band, two sets of proximity coupled stacked microstrip dipoles which crossed at the center are employed to achieve dual-linear polarization (DLP) and obtain desired

Microwave imaging is an efficient technique that can be used for the early detection of breast cancer. Therefore the current research article presents the microwave imaging of two spherical tumors (radius 4 and 5 mm) in the breast phantom by using the monostatic radar-based technique. This is carried out by using an ultra-wideband (4.9?10.9 GHz), three-layered stacked aperture coupled microstrip a

Multiple antennas and multiple radio frequency (RF) chains in both the transmitter and receiver are required in conventional radio systems employing the multiple-input multiple-output (MIMO) method. This paper presents an experimental investigation of a beam-steering time-modulated MIMO receiver with a single RF chain. Implementation of the receiver is based on a time-modulated antenna array (TMAA

This paper presents the integration and channel characterization of a highly integrated dual-band digital beamforming space-borne synthetic aperture radar (SAR) receiver. The proposed SAR sensor is a low-cost, lightweight, low-power consumption, and dual-band (X/Ka) dual-polarized module ready for the next-generation space-borne SAR missions. In previous works, by the authors, the design and exper

Early detection of breast cancer is required to increase the chances of a successful treatment. However, current breast-imaging systems such as X-Ray mammography, breast ultrasound, and magnetic resonance imaging have technological limitations so that novel solutions are needed to address this major societal problem. The current paper considers ultra-wideband (UWB) microwave radiation in the frequ

Airbus Italia recently developed enhanced passive components as key elements for its telecommunication Ku-band antenna product lines, tailored to reconfigurable payloads. This paper describes the design and qualification of a dual linear polarization Ku-band-radiating chain, developed for the DRA receive (Rx) active antennas embarked on the Eutelsat Quantum satellite. The feed chain covers the ent

In this paper, a novel miniaturized implantable circular antenna is presented. It supports both wireless information communication and wireless energy transmission at the Medical Device Radiocommunication band (MedRadio 402?405 MHz) and the industrial, scientific, and medical bands (ISM 902.8?928 MHz). The antenna is circular to avoid sharp edges while miniaturization is achieved by adding two cir

Electromagnetic waves in the microwave and millimeter-wave frequency range are used in non-destructive testing and structural health monitoring applications to detect material defects such as delaminations, cracks, or inclusions. This work presents a sensing concept based on guided electromagnetic waves (GEW), in which the waveguide forms a union with the structure to be inspected. Exploiting ultr

A flexible broadband antenna with high radiation efficiency for the Internet of Things (IoT) applications is presented. The design is based on a U-shaped and a triangular-shaped radiator with two tuning stubs. A 50 ? coplanar waveguide (CPW) transmission line is employed to feed the antenna. The proposed antenna is fabricated on a flexible substrate from a composite synthesized by mixing natural r

An inscribed hexagonal fractal slotted patch antenna with some additional geometry and slots is proposed for the optimization in this paper. This research work is concerned with the optimization of this slotted fractal antenna with the help of the curve-fitting method in conjunction with the modified version of Lightning Attachment Procedure Optimization (MLAPO) technique. The data required for th

Near-field to far-field transformations constitute a powerful antenna characterization technique for near-field measurement scenarios. In this paper, a near-field to far-field transformation technique based on multiple spherical wave expansions (SWEs) is presented. Thanks to its iterative matrix inversion nature, the approach performs the transformation of fields measured on arbitrary surfaces. Al

Microwave radars can be used to monitor the internal structure of the snowpack, delivering real-time and non-destructive measurements. Recently, the working principle of an innovative radar architecture able to identify some of the most important snowpack parameters, without external aids, has been demonstrated. A key point of this new architecture is the use of two independent receiving antennas,

In this article, a sleeve antenna with a wide impedance bandwidth that consists of a coplanar waveguide line connected to a metallic cylinder is presented. The effect of design parameters on the impedance bandwidth is considered by some simulations. In addition to the wide impedance bandwidth, the omnidirectional pattern, high efficiency, low cost and easy fabrication process, and compact dimensio