The design and performance of two wideband double leaky slot lens antennas, suitable for integration in commercial CMOS technologies, are presented. It is shown that antennas that are of leaky-wave nature are extremely suitable for CMOS integration as the impact of the metal density rules is minimized while simultaneously a dielectric lens can be efficiently illuminated. One antenna, operating over an ultra-wide bandwidth from 200GHz to 600GHz with a state-of-the-art simulated average efficiency of 57%, is suitable for center-fed direct detection scenarios. As a mean of antenna performance verification, a CPW-fed antenna, that operates from 250GHz to 500GHz with an average efficiency of 47%, is designed, fabricated and characterized. This antenna, that potentially could be interfaced to other on-chip active elements, is fabricated and characterized in terms of s-parameters and gain patterns with excellent agreement with simulation, thanks to the use of an ad-hoc quasi-optical measurement setup.

This article presents an efficient digital polar transmitter (DPTX) at mm-wave frequencies that exploit a novel $N$ -way series Doherty combiner (SDC) to enhance its drain and system efficiency at deep power back-off (PBO). The proposed $N$ -way SDC is scalable and can be implemented elegantly using $N$ transformers and $N-1$ shunt capacitors. As a proof of concept, a four-way Doherty DPTX is realized with the proposed SDC in which four identical but independent digital phase modulators deliver a phase-modulated constant envelope signal to their corresponding digital power amplifiers to perform the required amplitude modulation. Fabricated in a 40nm CMOS process, the proposed DPTX occupies a core area of 1.1 $\mathrm {mm^{2}}$ and exhibits 18.7dBm saturated output power and <−40dBc LO feedthrough. It demonstrates a drain efficiency of 33%/36%/22% at 0/4.5/11.5dB PBO at a 29.5GHz carrier frequency. While transmitting a 300MHz 64-QAM OFDM signal with a peak-to-average power ratio of 10.7dB, the DPTX achieves 18%/8% average drain/system efficiency, −27.6dB error vector magnitude, and −27.5dBc adjacent channel leakage ratio. To the best of our knowledge, this work is the first reported mm-wave Doherty transmitter that includes the entire chain all the way from the binary data stream up to the modulated mm-wave output signal.

The evolution of emerging technologies that use Radio Frequency Electromagnetic Field (RF-EMF) has increased the interest of the scientific community and society regarding the possible adverse effects on human health and the environment. This article provides NextGEM’s vision to assure safety for EU citizens when employing existing and future EMF-based telecommunication technologies. This is accomplished by generating relevant knowledge that ascertains appropriate prevention and control/actuation actions regarding RF-EMF exposure in residential, public, and occupational settings. Fulfilling this vision, NextGEM commits to the need for a healthy living and working environment under safe RF-EMF exposure conditions that can be trusted by people and be in line with the regulations and laws developed by public authorities. NextGEM provides a framework for generating health-relevant scientific knowledge and data on new scenarios of exposure to RF-EMF in multiple frequency bands and developing and validating tools for evidence-based risk assessment. Finally, NextGEM’s Innovation and Knowledge Hub (NIKH) will offer a standardized way for European regulatory authorities and the scientific community to store and assess project outcomes and provide access to findable, accessible, interoperable, and reusable (FAIR) data.

This work presents a novel dual-lens architecture using an electrically-small, non-diffractive core lens made of dense thermoplastics, and a large shell lens. The electrically-small core lens is fed efficiently by a leaky-wave feed that radiates a spherical wave in the near field. The leaky-wave feed is realized on a glass substrate that can be used as low-loss interposer for on-package antenna integration at D-band frequencies. A prototype using low-cost and mass-production plastic materials with one or two metal layers glass substrate has been developed and characterized. The measured prototype shows a directivity of more than 32dBi and a measured total loss of less than 2dB over a bandwidth of 30% and can be used as the array element for future communications systems based on Fly’s-Eye antenna architectures.

In this article, we present a comprehensive analysis of the hardware and software solutions required to enable frequency scalable load-pull test benches operating in the (sub)mm-wave frequency bands. First, the constraints arising from the harmonic (nonlinear) operation of mm-wave extender modules are discussed and analyzed. Then, different hardware solutions for signal generation and control, together with the specific software algorithms required to realize a frequency scalable load-pull test bench, are presented. The measurement setup key performances are analyzed in different frequency bands up to 500 GHz, i.e., waveguide bands from WR10 up to WR2.2. Finally, the load-pull measurements on an HBT device at 75 GHz and a two-stage differential PA at 135 GHz are presented to show the capability of the proposed test bench to characterize and optimize mm-wave nonlinear components.

In this contribution we present a numerical and experimental analysis of the multimode propagation over coplanar transmission lines, in order to define guidelines for substrate selection to achieve accurate wafer-level (sub)mm-wave calibrations. Losses and coupling effects resulting from the multiple propagating modes on transmission lines conventionally employed for probe-level calibrations, are analysed by means of 3D electro-magnetic simulations. A low loss-tangent, low dielectric constant material (i.e., fused silica), providing low radiation losses due to mode coupling, is proposed as substrate to achieve accurate (sub)mm-wave calibrations. The structures required to perform a TRL calibration are integrated on the proposed fused silica substrate and the experimental data of probe-level calibration performed in the 220-325GHz band are presented.