Analysis and design of an intra-coaxial reflected-power telemetry system

Failures of connectors used in radio frequency (RF) systems cost the telecom industry, mainly cellular phone providers, billions of dollars annually. This cost is incurred because the integrity of the connectors cannot currently be monitored in-system and failure results in catastrophic signal loss. The Smart Connector project aims to solve this problem by designing a connector with the capability to sense and report its own integrity. An integrated sensor chip has been developed that mounts on a molded inter-connect device inside of a coaxial cable connector. The current prototype system uses a direct connection to the chip to send the sensor data. However, for the system to be feasible in the target environment it must communicate sensor data wirelessly down the coaxial cable. The sensor chip uses a small loop coupler to inductively couple RF energy from the center conductor of the coaxial cable. The loop coupler is used to wirelessly receive power and to send and receive data from the sensor chip. Because the sensor chip is completely passive (it has no power source) the power available to transmit data is limited. The goal of this thesis is to develop a low power, wireless telemetry system for the Smart Connector sensor disk. This work investigates the analysis and design of an intra-coaxial cable reflected power communication system for use in the Smart Connector system. Theoretical analysis and experimentation proved the plausibility of using an intra-coaxial reflected power communication method for the telemetry system. Design guidelines were derived through the theoretical analysis which highlight many trade-offs and requirements for use in a final Smart Connector system. A simulation model of the communication link, which closely matches results from the theoretical model, was developed using the Cadence tool set. Finally, a complete prototype system capable of sending and receiving data packets via intra-coaxial cable reflected power communication was implemented

A 39-GHz Doherty-Like Power Amplifier with 22-dBm Output Power and 21% Power-Added Efficiency at 6-dB Power Back-Off

© 2024, IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. This is the accepted manuscript version of a conference paper which has been published in final form at https://doi.org/10.1109/JETCAS.2024.3351075The design of a Doherty-like power amplifier for millimetre-wave (mm-wave) applications is presented in this work. The designed power amplifier employs a novel symmetrical loadmodulated balanced amplifier (S-LMBA) architecture. This design is advantageous in minimizing the undesired impedance interaction often encountered in the classic LMBA approach. Such interactions are typically due to the use of a non-50 Ω load at the isolation port of the output quadrature coupler. Moreover, magnitude and phase control networks are carefully designed to generate the specific magnitude and phase information for the designed S-LMBA. To demonstrate the proposed ideas, the SLMBA is fabricated in a 45-nm CMOS SOI technology. At 39 GHz, a 22.1 dBm saturated output power (Psat) with a maximum poweradded efficiency (PAE) of 25.7% is achieved. In addition, 1.68 times drain efficiency enhancement is obtained over an ideal Class-B operation, when the designed S-LMBA is operated at 6 dB power back-off. An average output power of 13.1 dBm with a PAE of 14.4% at an error vector magnitude (EVMrms) above -22.5 dB and adjacent channel power ratio (ACPR) of -23 dBc is also achieved, when a 200 MHz single carrier 64-quadratureamplitude- modulation (QAM) signal is used. Including all testing pads, the footprint of the designed S-LMBA is only 1.56 mm2.Peer reviewe

Full-3D Printed Electronics Fabrication of Radiofrequency Circuits and Passive Components

[eng] This doctoral thesis raises the idea that 3D printing can change the paradigm of radio- frequency electronics, which has been traditionally developed mainly conceiving planar topologies. A review on additive manufacturing and the different existing technologies is reported. To focus on the concerning topic, several applications of 3D-printed electronics in the RF field are collected to elaborate the State-of-the-Art. The main objectives of this project is to develop a 3D manufacturing technology for RF electronics passive components and circuits and to generate innovative research about the possibilities of AM in this area. Once the context is exposed, the manufacturing process for 3D-printed electronics developed within the frame of this project is described and characterized. This technology consists of three different steps. First of all, the 3D model of the prototype is designed using a CAD environment with electromagnetic simulation features, hence size parameters are adjusted to fit the specifications. Hereon, the 3D polymer substrate is printed by using either stereolithography or material jetting techniques. Stereolithography is found to be a cheaper AM technology while material jetting offers a better printing resolution and softer surface endings. Finally the object is partially metallized to obtain the conductive layer of the component or circuit using an electrolytic process, such as electroless plating or electroplating. The characterization includes the electromagnetic specifications of the dielectric substrates (i.e. the dielectric constant and the loss tangent) and the quality of the metallization (i.e. the resistivity and the layer thickness). The results of the plating resitivity are found to be competitive compared to the SoA. In order to demonstrate the possibilities of the developed technology, several devices are designed and tested. The key factor of these prototypes is that they would be very difficult, costly or impossible to manufacture using conventional technologies. As a preliminary demonstration, a hello-world circuit to turn on a LED proves that almost any kind of shape can be plated, including vias; both through hole and SMD components can be soldered and that mechanical stress such as USB plugging is resisted by the metal layer. In addition, a study on conical inductors is carried out showing the advantages of these components for broadband applications with compact devices. They offer a larger bandwidth cylindrical solenoids and are more compact than planar coils. As an application example, they are used in the manufacturing of 3D passive filters. The prototypes present agreement with simulations and the ideal response. Slight discrepancies are caused by the manufacturing tolerances. Moreover, 3D filters are also designed as one single-printed part, a new technique for 3D discrete component integration. That permits to reduce the number of components to assembly so that it does not increase with the order of the filter. These single 3D-printed prototypes present improvement in performance and compactness as well. In addition to the lumped circuits, a whole chapter is dedicated to distributed-element devices. A study on helical-microstrip transmission lines is carried out showing an important enhancement for line segment miniaturization. Hereon, they are implemented on the design of impedance transformers, which also benefit from bandwidth broadening. Another proposed device is the hybrid branch-line coupler, which, besides the implementation of helical lines, it has been designed conceiving a capacitively loaded folded structure. This coupler gives very interesting results in compactness improvement, without significant reduction of the bandwidth. The prototypes have been compared to the conventional topology as well as to other designs found within the SoA. Finally, helical-microstrip coupled-line couplers have also been designed, fabricated and studied. They offer a good enhancement in terms of compactness though it goes in slight detriment of the coupling factor due to the manufacturing tolerances.[cat] Aquesta tesi doctoral proposa la idea que la impressió 3D pot canviar el paradigma de l’electrònica de radiofreqüència. S’hi anomenen i expliquen les tecnologies de manufactura additiva existents. Per centrar-se en el principal tema d’interès, s’exposa un compendi d’aplicacions d’electrònica impresa en 3D en el camp de la RF amb el qual s’ha confeccionat l’estat de la qüestió. Un cop exposat el context, el procés de manufactura per a electrònica impresa en 3D que s’ha desenvolupat en el marc d’aquest projecte és descrit i caracteritzat. Aquesta tecnologia consisteix en la impressió en 3D d’un substrat de polímer utilitzant tècniques basades, o bé en estereolitografia, o bé en material jetting. Posteriorment, el component o circuit es metal·litza parcialment mitjançant un procés electrolític ja sigui electroless plating o electroplating. La caracterització inclou les especificacions electromagnètiques del substrat dielèctric i la qualitat de metal·lització, que s’han resultat ser competitives relació amb l’estat de la qüestió. Amb l’objectiu de demostrar les possibilitats de la tecnologia desenvolupada, s’han dissenyat i testejat dispositius electrònics de RF, concebent-los en l’espai tridimensional. El punt clau és que els dispositius dissenyats serien molt difícils, costosos o directament impossibles de fabricar usant tecnologies convencionals. A remarcar, s’ha dut a terme un estudi sobre inductors cònics, mostrant els avantatges d’aquests components per a aplicacions de banda ampla amb dispositius compactes. Aquests inductors shan fet servir per a la fabricació de filtres passius en 3D. A més, a més, s’han dissenyat filtres 3D per ser impresos en una sola part, una tècnica nova que per produir circuits 3D amb components discrets integrats. A part dels circuits d’elements discrets, s’ha dedicat un capítol sencer als dispositius d’elements distribuïts. S’ha dut a terme un estudi sobre línies de transmissió microstrip helicoidals, les quals aporten una millora important de miniaturització dels segments de línia. Partint d’aquí, aquestes línies s’han implementat en el disseny de transformadors d’impedància, que també milloren en termes d’ample de banda, acobladors híbrids de tipus branch-line i acobladors basats en línies acoblades. Aquests dispositius han resultat tenir millores importants de compacitat respecte els dissenys convencionals fabricats en estructures planars

Feasiblity study for a 34 GHz (Ka band) gyroamplifier

The feasibility of using a gyroklystron power tube as the final amplifier in a 400 kW CW 34 GHz transmitter on the Goldstone Antenna is investigated. A conceptual design of the gyroklystron and the transmission line connecting it with the antenna feed horn is presented. The performance characteristics of the tube and transmission line are compared to the transmitter requirements for a deep space radar system. Areas of technical risk for a follow-on hardware development program for the gyroklystron amplifier and overmoded transmission line components are discussed

A 2.4 GHz CMOS class-F power amplifier with reconfigurable load-impedance matching

© 2019 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.A novel reconfigurable CMOS class-F power amplifier (PA) at 2.4 GHz is proposed in this paper. It is able to match the output load variations mainly due to the effect of hand and head on a mobile phone. The effect of load variation on power-added efficiency (PAE), output power, and distortion is compensated by reconfiguring the output network using an impedance tuner. The tuner controls the output matching at fundamental frequency without affecting the class-F harmonic tuning up to 3rd harmonic. To the best of our knowledge, this is the first design of a CMOS class-F PA addressed to compensate the effect of load variation. Measurement results for 50 ohm load impedance show a maximum PAE of 26% and maximum output power of 19.2 dBm. The measured total harmonic distortion is 4.9%. Measurement results for load values other than 50 ohm show that PAE increases from 6.5% (not-tuned PA) up to 19.9% (tuned PA) with the same output power (19.2 dBm). Tuning also reduces the adjacent-channel leakage ratio by 5 dB and the spectral regrowth of a Wi-Fi signal at the PA output. The size of the fabricated chip is 1.6 mm × 1.6 mm.Peer ReviewedPostprint (author's final draft

A 40-GHz Load Modulated Balanced Power Amplifier using Unequal Power Splitter and Phase Compensation Network in 45-nm SOI CMOS

© 2023 IEEE - All rights reserved. This is the accepted manuscript version of an article which has been published in final form at https://doi.org/10.1109/TCSI.2023.3282731 ​​​​​​​In this work, a ten-way power-combined poweramplifier is designed using a load modulated balanced amplifier(LMBA)-based architecture. To provide the required magnitudeand phase controls between the main and control-signal paths ofthe LMBA, an unequal power splitter and a phase compensationnetwork are proposed. As proof of concept, the designed poweramplifier is implemented in a 45-nm SOI CMOS process. At 40GHz, it delivers a 25.1 dBm Psat with a peak power-addedefficiency (PAE) of 27.9%. At 6-dB power back-off level, itachieves 1.39 times drain efficiency enhancement over an idealClass-B power amplifier. Using a 200-MHz single-carrier 64-QAMsignal, the designed amplifier delivers an average output power of16.5 dBm with a PAE of 13.1% at an EVMrms of -23.9 dB andACPR of -25.3 dBc. The die size, including all testing pads, is only1.92 mm2. To the best of the authors’ knowledge, compared withthe other recently published silicon-based LMBAs, this designachieves the highest Psat.Peer reviewe

Josephson parametric reflection amplifier with integrated directionality

A directional superconducting parametric amplifier in the GHz frequency range is designed and analyzed, suitable for low-power read-out of microwave kinetic inductance detectors employed in astrophysics and when combined with a nonreciprocal device at its input also for circuit quantum electrodynamics (cQED). It consists of an one wavelength long nondegenerate Josephson parametric reflection amplifier circuit. The device has two Josephson junction oscillators, connected via a tailored impedance to an on-chip passive circuit which directs the in- to the output port. The amplifier provides a gain of 20 dB over a bandwidth of 220 MHz on the signal as well as on the idler portion of the amplified input and the total photon shot noise referred to the input corresponds to maximally 1.3 photons per second per Hertz of bandwidth. We predict a factor of four increase in dynamic range compared to conventional Josephson parametric amplifiers.Comment: Main article (5 pages plus 2 pages references) plus supplemental material (14 pages

Fast start of oscillations in a short-pulse relativistic magnetron driven by a transparent cathode.

The magnetron has been a major component of radar systems since its introduction in World War II. The newer radar techniques require high peak power (GW) and short microwave pulses (few ns). To serve as a microwave source for short-pulse applications it is imperative that the magnetron needs to have both fast start and fast rate of build-up of oscillations. Both of these factors are contingent on the cathode geometry. The transparent cathode was invented at the University of New Mexico in an endeavor to improve the start time and increase the rate of build-up of oscillations in short-pulse relativistic magnetrons. The construction of the transparent cathode involves the removal of longitudinal strips of material from a hollow cathode. The resultant geometry has manifold advantages the first and the foremost of which is that it makes the cathode transparent to E_theta, thereby greatly increasing its amplitude where electrons are emitted. Hence one would expect faster rate of build-up of oscillations. Secondly, this geometry simultaneously gives rise to several different forms of priming: cathode priming, electrostatic priming and magnetic priming. The number of cathode strips is chosen so that it would excite a particular mode of interest (e.g. 6 strips would favor the formation of 6 spokes). The cathode strips may be oriented azimuthally in a manner that the electron bunches from the cathode strips would be released into the favorable phase of the mode of interest where efficient exchange of energy between the electrons and the RF fields could take place. The highlights of this dissertation are proof-of-concept computer simulations demonstrating the benefits of the transparent cathode in an A6 magnetron driven by a transparent cathode that have validated the simulations

Design of Tunable Beamforming Networks Using Metallic Ridge Gap Waveguide Technology

Wireless communication is a leap of development in the history of humanity. For the past 100 years, a considerable effort has been spent to develop better standards, and technologies for a higher speed wireless communication with high system capacity for different applications. This requires the design of a high-frequency, point-to-multipoint antenna array system to achieve the mentioned goals. In addition, the reconfigurability of this antenna system is essential to change the system characteristics to achieve acceptable performance in different situations. The main goal of this thesis is to design a reconfigurable beamforming network to work on the Ka-band for waveguide applications. Among different beamforming networks in the literature, the Butler matrix is chosen due to its higher efficiency and the smaller number of components required than other beamforming networks. The Butler matrix is designed using a dual-plane topology to avoid using crossovers. Ridge gap waveguide technology is chosen among different transmission lines to implement the Butler matrix for several reasons: It does not need dielectrics to operate, so its power handling capacity is defined by the gap height, and it has no dielectric losses. Its zero-field region represents the operating principle for some tunable devices introduced here and its contactless nature, which eases the assembly of waveguide parts at the millimeter-wave frequencies. The reconfigurability of the Butler matrix is implemented such that beamwidth, maximum gain, and beam direction may be all tuned for optimum system performance. To that end, several components are designed to achieve the required target, and strict requirements are placed on several components to achieve an acceptable cascaded-system performance. These components include a ridge gap waveguide 90o-hybrid working over a more than 30% bandwidth, which can provide several coupling levels ranging from 3 dB to 33 dB and a return loss and isolation better than 30 dB. Another component is a wideband reconfigurable power splitter that has a 40% bandwidth, a return loss better than 20 dB in the worst case and the ability to achieve all power splitting ratios including switching between the two guides. In addition, a wideband reconfigurable phase shifter is designed to have 33% bandwidth and phase shift tuning range from 0o to 200o. Two coaxial-to-ridge gap waveguide transitions are designed to work over a more than 100% bandwidth to facilitate testing different ridge gap waveguide components. Analysis of the asymmetric double ridge waveguide is introduced where its impedance is deduced and may be used to design a single to double ridge waveguide transition useful for the dual-plane Butler matrix introduced here. In addition, this concept is used to develop a wideband unequal power divider in the single ridge waveguide technology. At the end, the whole system is assembled to show its performance in different tuning states. The ability of the system to produce radiation patterns of different characteristics is demonstrated. The presented Butler matrix design is a promising beamforming network for several applications like radar, base stations for mobile communications, and satellite applications