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Pultrusion is the process for production of semi-product composite profiles with carbon or glass fiber reinforcements [1], [2]. The glass or carbon fibers are mixed with resin (phenolic or epoxy) and pulled trough a shaping die. During this process heat is applied for curing the resin and getting a solid material. Today, conventional heating methods are used. At this place, a microwave applicator...
A bandstop filter architecture with small form factor and very large attenuation over an octave frequency tuning range is demonstrated. The architecture provides a benefit of resonator-Q-independent zero reflection coefficient at the center frequency, and is demonstrated with a tuning range of 55.04 to 133.34 MHz varactor-tuned two-resonator notch filter with minimum notch attenuation of 64 dB, 3-dB...
For the conventional Doherty power amplifiers, asymmetrical cells are used to achieve high efficiency over large (> 6 dB) output power dynamic ranges, i.e. larger class-C cell. In this paper, it will be theoretically proven that high efficiency over large dynamic ranges also can be achieved using symmetrical devices, while still maintaining full voltage and current swing of both transistor cells...
In this paper, a signal amplitude estimator for inter-band carrier aggregated signals is proposed to assist with the effective application of dual-band crest factor reduction (CFR) and digital predistortion (DPD) for enhanced dual-band power amplifier (PA) performance. As proof of concept validation, the dual-band CFR was applied to reduce the peak to average power ratio of a carrier aggregated signal...
This paper presents a dual-band envelope tracking power amplifier (ET PA) capable of amplifying concurrent dual-band modulated signals using a typical single-band envelope amplifier. The dual-band ET PA succeeded to concurrently amplify widely spaced dual-band modulated signals with balanced and imbalanced output powers in each band. The dual-band ET PA was linearized using dual-band Volterra based...
An ℌ2-matrix based linear-complexity direct matrix solution for the volume integral equation (VIE) is developed for the broadband full-wave extraction of general 3-D circuits, containing arbitrarily shaped lossy conductors immersed in inhomogeneous dielectrics, with ports located anywhere in the physical layout of the circuit. A well-conditioned VIE formulation, without sacrificing any advantage of...
For microstrip patch phased arrays, larger fractional bandwidth (FBW) and wider scan angle are challenging to achieve at the same time. Phased arrays on thin substrates typically can scan to large angles due to the reduction of mutual coupling caused by surface waves. However, thin substrates limit the achievable FBW of the phased array antenna. In this paper, an integrated filter/patch technology...
Recent research on parameter uncertainty quantification via the Finite-Difference Time-Domain (FDTD) method has led to several approaches aimed at outperforming the conventional Monte-Carlo technique. Among those, the use of polynomial chaos (PC) is characterized by mathematical robustness and computational efficiency. However, it still requires either multiple FDTD runs (in non-intrusive PC methods)...
Two wideband amplifier MMICs are designed and tested. Both designs employ InP double-heterojunction bipolar transistor technology. The amplifiers are designed using cascode cells, in a distributed amplifier topology, with simple on-chip resistive bias circuitry. A single stage design achieves 7.5 dB gain and 192 GHz bandwidth and a 2-cascaded distributed amplifier achieves gain in excess of 16 dB...
A directional coupler using edge coupled lines is designed and fabricated on a two-layer PCB with isolation being achieved through electrical balance. Measured results show 4dB coupling and 34dB isolation at a frequency of 2.5GHz with 16% matching bandwidth (−10dB). Isolation varies between 31dB to 36dB in the 2.3GHz to 3GHz frequency range.
This paper presents the system performance and flight testing of an advanced technology demonstrator for a low-cost and small size near-field obstacle warning sensor for civil and military helicopters. Based on the previously developed sensor modules, the complete sensor system was successfully tested during flight tests and the results of the visualization of various obstacles detected like antennas,...
A new Padé behavioral model dependent on the magnitude of the load reflection coefficient is presented. With this model, we need only sweep the magnitude of reflection coefficient, |ΓL|, to cover the whole Smith chart, instead of sweeping both phase and magnitude when performing model extraction. This greatly simplifies the model extraction process from a 2D-load-pull sweep to a 1D sweep. Both simulation...
A microstrip differential-mode (balanced) bandpass filter covering the frequency spectrum assigned for ultra-wideband (UWB) communications (3.1GHz–10.6GHz) is presented. The main relevant characteristics of the proposed filter are: (i) the good stop band performance above the band of interest, with high selectivity, harmonic suppression and broad rejection bandwidth, achieved thanks to the embedded...
This report describes a Ku-band amplifier GaN MMIC. The amplifier MMIC delivers a measured saturated power of 20 W and gain of 20 dB under CW operation. To enhance the linearity of the two stage amplifier composed of the MMIC and GaN Internally Matched FET, a diode linearizer has also been built into the MMIC. The linearizer offers 5dB better linear output power, defined the output power at IM3 of...
An efficient fundamental locally one-dimensional finite difference time domain (FLOD-FDTD) method including lumped elements is presented. The FLOD-FDTD achieves higher efficiency and simplicity with the removal of matrix operators in the right-hand sides. The updating equations of the FLOD-FDTD method incorporating resistors, inductors and capacitors are derived. Numerical results are provided to...
In this letter, a quad-mode single band bandpass filter and a dual-mode dualband bandpass filter are designed and fabricated by the same structure (two coupled dual-mode loop resonators), which consist of an outer loop resonator with square-patch perturbation at the corner and a inner loop resonator with corner-cut perturbation at the corner. Four transmission zeros are realized in the stopbands to...
Previously reported 100-Gbit/s wireless links have been based on an off-line digital signal processing and/or have assumed a use of forward-error correction (FEC) technique. In this paper, we discuss a strategy for real-time/error-free 100-Gbit/s transmission using photonically-assisted signal generation and modulation techniques at 300 GHz, and demonstrate some of our recent results towards 100-Gbit/s...
This paper presents a quad-band filter using a set of stub-loaded quarter-wavelength resonators operated at the first and fourth passbands (1.8/5.8 GHz) and a set of stub-loaded half-wavelength SIRs operated at the second and third passbands (2.4/3.5 GHz). Furthermore, both of the loading stub are used to generate another passband. This study provides an effective method to design a quad-band filter...
This paper presents a high speed and low distortion sampler with two-channel time-interleaved sampler with track-and-hold amplifier (THA). The THA is based on switched source-follower with active inductor load such that wide bandwidth in tack-mode and small signal feed-through in hold-mode can be both achieved within compact area. Furthermore, one clock-controlled auxiliary transistor is also introduced...
A dc-80 GHz compact distributed amplifier (DA) with 15-dB small signal gain is developed in 40-nm CMOS digital process. The circuit architecture is based on the conventional DA (CDA) with gain cell of cascaded single-stage DA (CSSDA). In order to minimize the chip size, the artificial transmission-line sections of DA are implemented with microstrip-line instead of coplanar-waveguide (CPW), and the...
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