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A new modulator for digital RF power amplifiers utilizing a wavetable approach
This paper presents for the first time a wavetable-based coding scheme to generate a high-speed binary input signal for digital RF power amplifiers. The approach maximizes the utilization of the time domain handling capabilities of the pulse forming circuit. Key features are a greatly improved output spectrum purity in comparison with common digital modulators, the ability to adjust the modulator
Recognition of jet engines via sparse decomposition of ISAR images using a waveguide scattering model
Air target recognition is a critical step in the radar processing chain and reliable features are necessary to make a decision. The number and position of jet engines are useful features to perform a pre-classification and give a list of possible targets. To extract these features, a sparse decomposition framework for inverse synthetic aperture radar (ISAR) images is presented. With this framework
Waveform diversity for SAR ECCM based on random phase and code rate transition
In this paper, we propose an effective waveform diversity scheme that can be applicable to synthetic aperture radar (SAR) operations affected by interfering signals. A novel approach is taken to achieve fully adaptive SAR waveform diversity that generates sufficient number of orthogonal signals with modest performance trade-off. To this purpose, multiple phased-code waveforms are arbitrarily gener
Broadband sub-THz spectroscopy modules integrated in 65-nm CMOS technology
The design and characterization of a broadband 20?480 GHz continuously tuneable on-chip spectrometer based on non-linear transmission lines in 65-nm CMOS technology is presented. The design procedure of the sampler that detects the ultra-broadband signal from the transmitter in time and frequency domain is described in detail. It consists of a non-linear transmission line, a passive pulse differen
Development of a 70 MHz unit for hyperthermia treatment of deep-seated breast tumors
A dedicated hyperthermia (HT) system was designed for tumors in intact breast extending beyond the heating depth of our superficial 434 MHz antennas, consisting of a treatment bed fitted with a 50 cm × 40 cm × 16 cm temperature controlled open water bolus. The patient lies in prone position with the breast immersed in the water positioned in front of a 34 cm × 20 cm 70 MHz waveguide operating in t
Efficient 2-D leaky-wave antenna configurations based on graphene metasurfaces
Different configurations of leaky-wave antennas (LWAs) based on graphene metasurfaces are studied. The electronic properties of a graphene metasurface in the low THz range are investigated in details in order to discuss the reconfigurability features of the presented structures. Simple exact formulas for evaluating the ohmic losses related to the surface plasmon polariton (SPP) propagation along a
A 0.4?3-GHz nested bandpass filter and a 1.1?1.7-GHz balun bandpass filter using tunable band-switching technique
This paper presents a second-order tunable single-ended (unbalanced) bandpass filter (BPF) with continuous 0.4?3-GHz coverage and a tunable balun BPF with continuous 1.1?1.7-GHz coverage for software-defined radio transceivers with the use of band-switchable and radio frequency (RF)-micro-electromechanical systems (MEMS)-tuned resonators. The BPFs are realized with two pairs of RF switches for coa
An efficient W-band InP DHBT digital power amplifier
This paper presents for the first time high-efficiency W-band power amplifiers (PAs), the design of which follows the digital PA (DPA) design concept. Two DPAs with different output networks have been realized: a single-band version (S-DPA) for 95 GHz and a dual-band design (D-DPA) for signal frequencies f of 68 GHz (first band) and 76 GHz (second band), respectively. The PAs are realized as monol
EuMC: Realization of Single-Layer Ka-Band Dual-Mode Substrate Integrated Waveguide Filters and Diplexer Using a Circular Cavities with Via Perturbation
Proceedings of the 47th European Microwave Conference Realization of Single-Layer Ka-Band Dual-Mode Substrate Integrated Waveguide Filters and Diplexer Using a Circular Cavities With Via Perturbation State Research Dept., Huawei Technologies Corporation, Shanghai, China Key Lab. Of Millimeter Waves, Dept. of Radio Engineering Southeast University, Nanjing, P.R.China Email: weichenhseu@gmail.co
EuMC: Properties of Antennas Made with Sprayed Selective Silver Metallization
Proceedings of the 47th European Microwave Conference Properties of Antennas Made with Sprayed Selective Silver Metallization Arnaud Jammes, Michael Petisme, Koen Staelens JET METAL TECHNOLOGIES R&D, Champagne au Mont D'Or 69410, France Email: info@jetmetal-tech.com Abstract-- This paper starts with the description of a new direct chemical plating method for silver, called the JET METAL (JMT) pro