Journal articles: 'Conjugate Impedance Matching Techniques'

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Brufau-Penella, J., and M. Puig-Vidal. "Piezoelectric Energy Harvesting Improvement with Complex Conjugate Impedance Matching." Journal of Intelligent Material Systems and Structures 20, no. 5 (November 28, 2008): 597–608. http://dx.doi.org/10.1177/1045389x08096051.

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One way to enhance the efficiency of energy harvesting systems is complex conjugate impedance matching of its electrical impedance. In Piezoelectric energy Harvesting systems the match is done to increment the energy flows from a vibration energy source to an energy storage electrical circuit. In this article, we compare the power generated using the modulus impedance matching with the power generated using the complex conjugate impedance matching. We present the power ratio between both types of matching methods. The novelty of this article consists of a piezoelectric transducer completely adapted with a complex conjugate impedance match. The theory developed is validated on a commercial piezoelectric transducer QP40w from Midé Technology. The transducer model is first identified by means of a system identification step based on a novel two-port Lumped-Electromechanical Model. The QP40w is complex conjugate matched at its fourth resonant mode increasing the generated power by up to 20% more compared with the modulus match.

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Wang, Hong Yan, Xiao Biao Shan, and Tao Xie. "Complex Impedance Matching for Power Improvement of a Circular Piezoelectric Energy Harvester." Applied Mechanics and Materials 148-149 (December 2011): 169–72. http://dx.doi.org/10.4028/www.scientific.net/amm.148-149.169.

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The impedance matching and the optimization of power from a circular piezoelectric energy harvester with a central-attached mass are studied. A finite element model is constructed to analyze the electrical equivalent impedance of the circular piezoelectric energy harvester. Furthermore, the complex conjugate matching load is used to extract the maximum output power of the energy harvester. The power output from complex conjugate matching load is compared with the power output from the resistive matching load and a constant resistance, separately. The results suggest that the complex conjugate matching can result in a significant increase of the output power for all frequencies. The effective bandwidth of the piezoelectric energy harvester is extended significantly.

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Cioffi, K. R. "Broad-band distributed amplifier impedance-matching techniques." IEEE Transactions on Microwave Theory and Techniques 37, no. 12 (1989): 1870–76. http://dx.doi.org/10.1109/22.44096.

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Sharma, Sonia, C. C. Tripathi, and Rahul Rishi. "Impedance Matching Techniques for Microstrip Patch Antenna." Indian Journal of Science and Technology 10, no. 28 (February 1, 2017): 1–16. http://dx.doi.org/10.17485/ijst/2017/v10i28/97642.

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Wang and Cao. "A Review of Impedance Matching Techniques in Power Line Communications." Electronics 8, no. 9 (September 12, 2019): 1022. http://dx.doi.org/10.3390/electronics8091022.

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Impedance mismatch that degrades signal power transfer and affects communication reliability is a major obstacle for power line communications (PLC). Impedance matching techniques can be designed to effectively compensate for the impedance mismatch between PLC modems and power line networks at a specific frequency or for a given frequency band. In this paper, we discuss the tradeoffs that need to be made when designing an effective impedance matching network. We also make a comprehensive review of previous state-of-the-art PLC impedance matching techniques and provide a useful classification of each technique. Finally, we discuss important issues (concerns) and provide suggestions for research directions deserving more attention. This review provides a useful guideline for researchers and manufacturers to quickly understand impedance matching principles and facilitate the design of an effective impedance matching coupler for PLC applications.

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Rathod, Vivek T. "A Review of Electric Impedance Matching Techniques for Piezoelectric Sensors, Actuators and Transducers." Electronics 8, no. 2 (February 1, 2019): 169. http://dx.doi.org/10.3390/electronics8020169.

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Any electric transmission lines involving the transfer of power or electric signal requires the matching of electric parameters with the driver, source, cable, or the receiver electronics. Proceeding with the design of electric impedance matching circuit for piezoelectric sensors, actuators, and transducers require careful consideration of the frequencies of operation, transmitter or receiver impedance, power supply or driver impedance and the impedance of the receiver electronics. This paper reviews the techniques available for matching the electric impedance of piezoelectric sensors, actuators, and transducers with their accessories like amplifiers, cables, power supply, receiver electronics and power storage. The techniques related to the design of power supply, preamplifier, cable, matching circuits for electric impedance matching with sensors, actuators, and transducers have been presented. The paper begins with the common tools, models, and material properties used for the design of electric impedance matching. Common analytical and numerical methods used to develop electric impedance matching networks have been reviewed. The role and importance of electrical impedance matching on the overall performance of the transducer system have been emphasized throughout. The paper reviews the common methods and new methods reported for electrical impedance matching for specific applications. The paper concludes with special applications and future perspectives considering the recent advancements in materials and electronics.

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Dasgupta, K., A. Dutta, and T. K. Bhattacharyya. "Parasitic aware impedance matching techniques for RF amplifiers." Analog Integrated Circuits and Signal Processing 70, no. 1 (June 5, 2011): 91–102. http://dx.doi.org/10.1007/s10470-011-9659-9.

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van Bezooijen, A., M. A. de Jongh, F. van Straten, R. Mahmoudi, and A. van Roermund. "Adaptive Impedance-Matching Techniques for Controlling L Networks." IEEE Transactions on Circuits and Systems I: Regular Papers 57, no. 2 (February 2010): 495–505. http://dx.doi.org/10.1109/tcsi.2009.2023764.

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HEMMINGER, THOMAS L. "ANTENNA IMPEDANCE MATCHING WITH NEURAL NETWORKS." International Journal of Neural Systems 15, no. 05 (October 2005): 357–61. http://dx.doi.org/10.1142/s0129065705000335.

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Impedance matching between transmission lines and antennas is an important and fundamental concept in electromagnetic theory. One definition of antenna impedance is the resistance and reactance seen at the antenna terminals or the ratio of electric to magnetic fields at the input. The primary intent of this paper is real-time compensation for changes in the driving point impedance of an antenna due to frequency deviations. In general, the driving point impedance of an antenna or antenna array is computed by numerical methods such as the method of moments or similar techniques. Some configurations do lend themselves to analytical solutions, which will be the primary focus of this work. This paper employs a neural control system to match antenna feed lines to two common antennas during frequency sweeps. In practice, impedance matching is performed off-line with Smith charts or relatively complex formulas but they rarely perform optimally over a large bandwidth. There have been very few attempts to compensate for matching errors while the transmission system is in operation and most techniques have been targeted to a relatively small range of frequencies. The approach proposed here employs three small neural networks to perform real-time impedance matching over a broad range of frequencies during transmitter operation. Double stub tuners are being explored in this paper but the approach can certainly be applied to other methodologies. The ultimate purpose of this work is the development of an inexpensive microcontroller-based system.

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Arai, Takaya, and Hiroshi Hirayama. "Folded Spiral Resonator with Double-Layered Structure for Near-Field Wireless Power Transfer." Energies 13, no. 7 (April 1, 2020): 1581. http://dx.doi.org/10.3390/en13071581.

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In this paper, a folded spiral resonator with a double-layered structure for near-field wireless power transfer is proposed. In near-field wireless power transfer, conjugate impedance matching is important to achieve high transfer efficiency. To achieve maximum available efficiency, it is common to connect a matching circuit to the antenna. However, the loss increases if a matching circuit is used. A coupling inductor with a resonant capacitor has the capability to adjust an imaginary part of the input impedance, whereas the folded spiral resonator has the capability to adjust both the imaginary and real parts of the input impedance. This resonator can achieve the maximum available efficiency without a matching circuit. This paper shows that the folded spiral resonator with a double-layered structure realizes high transfer efficiency compared to conventional models.

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Rathod, Vivek T. "A Review of Acoustic Impedance Matching Techniques for Piezoelectric Sensors and Transducers." Sensors 20, no. 14 (July 21, 2020): 4051. http://dx.doi.org/10.3390/s20144051.

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The coupling of waves between the piezoelectric generators, detectors, and propagating media is challenging due to mismatch in the acoustic properties. The mismatch leads to the reverberation of waves within the transducer, heating, low signal-to-noise ratio, and signal distortion. Acoustic impedance matching increases the coupling largely. This article presents standard methods to match the acoustic impedance of the piezoelectric sensors, actuators, and transducers with the surrounding wave propagation media. Acoustic matching methods utilizing active and passive materials have been discussed. Special materials such as nanocomposites, metamaterials, and metasurfaces as emerging materials have been presented. Emphasis is placed throughout the article to differentiate the difference between electric and acoustic impedance matching and the relation between the two. Comparison of various techniques is made with the discussion on capabilities, advantages, and disadvantages. Acoustic impedance matching for specific and uncommon applications has also been covered.

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Mo, Lingfei, and Chunfang Qin. "Tunable Compact UHF RFID Metal Tag Based on CPW Open Stub Feed PIFA Antenna." International Journal of Antennas and Propagation 2012 (2012): 1–8. http://dx.doi.org/10.1155/2012/167658.

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For the ultrahigh frequency radio frequency identification (UHF RFID) metal tag, it always has the difficulties of compact designing, especially for the conjugate impedance matching, low antenna gain, and fabrication or environmental detuning. In this paper, a tunable compact UHF RFID metal tag is designed based on CPW open stub feed PIFA antenna. By changing the length of the open stub, the impedance of the PIFA antenna could be tuned in a large scale for conjugate impedance matching. The open stub makes it easy to tune the resonant frequency to alleviate the fabrication detuning or the environmental detuning, even after the manufacture. Moreover, the CPW structure of the open stub feed can resist the effects of the metallic surface and increase the antenna gain for the compact PIFA antenna. Modeling analysis and simulation are in good agreement with the measurement results. It showed that the UHF RFID metal tag could be designed compact with good performance based on the CPW open stub feed PIFA antenna.

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Kim, Hyeoungwoo, Shashank Priya, Harry Stephanou, and Kenji Uchino. "Consideration of Impedance Matching Techniques for Efficient Piezoelectric Energy Harvesting." IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control 54, no. 9 (September 2007): 1851–59. http://dx.doi.org/10.1109/tuffc.2007.469.

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Evseev, Vladimir, Mikhail Ivlev, Stanislav Morugin, and Sergey Nikulin. "Construction of models of microwave transistors when changing the probing signal in the frequency and power range." ITM Web of Conferences 30 (2019): 01010. http://dx.doi.org/10.1051/itmconf/20193001010.

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It is shown that to model a transistor in the form of S-parameters in the large signal mode, it is necessary to present the model as two S-matrices that describe the transistor at two phase differences between the incident and reflected waves equal to 0 and 90 degrees. The problem of matching a transistor with a load is reduced to solving a nonlinear equation with respect to a previously unknown phase difference, after which the load impedance is selected from the complex-conjugate matching condition.

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Liu, Yun. "Synthesis Techniques on Multiband Impedance Matching Networks for Frequency-Dependent Complex Loads." IEEE Transactions on Microwave Theory and Techniques 66, no. 10 (October 2018): 4507–19. http://dx.doi.org/10.1109/tmtt.2018.2859920.

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Cho, Kyung Ho, Dong-Jin Shin, Chang Soo Lee, and Jung-Hyuk Koh. "Impedance Matching Techniques of Multi-layered PZT Ceramics for Piezoelectric Energy Harvesters." Electronic Materials Letters 15, no. 4 (March 29, 2019): 437–43. http://dx.doi.org/10.1007/s13391-019-00135-w.

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Hintzen, E., T. Vennemann, and W. Mathis. "Systematic design of output filters for audio class-D amplifiers via Simplified Real Frequency Technique." Advances in Radio Science 12 (November 10, 2014): 49–52. http://dx.doi.org/10.5194/ars-12-49-2014.

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Abstract. In this paper a new filter design concept is proposed and implemented which takes into account the complex loudspeaker impedance. By means of techniques of broadband matching, that has been successfully applied in radio technology, we are able to optimize the reconstruction filter to achieve an overall linear frequency response. Here, a passive filter network is inserted between source and load that matches the complex load impedance to the complex source impedance within a desired frequency range. The design and calculation of the filter is usually done using numerical approximation methods which are known as Real Frequency Techniques (RFT). A first approach to systematic design of reconstruction filters for class-D amplifiers is proposed, using the Simplified Real Frequency Technique (SRFT). Some fundamental considerations are introduced as well as the benefits and challenges of impedance matching between class-D amplifiers and loudspeakers. Current simulation data using MATLAB is presented and supports some first conclusions.

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Marrocco, Gaetano. "The art of UHF RFID antenna design: impedance-matching and size-reduction techniques." IEEE Antennas and Propagation Magazine 50, no. 1 (February 2008): 66–79. http://dx.doi.org/10.1109/map.2008.4494504.

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Han, Sang-Min, Yongwan Lee, Taemin Choi, Seok-Jae Lee, Jung-Woo Baik, Jongsik Lim, and Dal Ahn. "Compact Wake-Up Module Design Based on an Energy-Harvesting Rectenna for Wireless Sensor Receivers." International Journal of Antennas and Propagation 2015 (2015): 1–7. http://dx.doi.org/10.1155/2015/976875.

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A new compact energy-harvesting module is proposed with compact design techniques. The rectifying circuit eliminates the band-pass filter and matching circuit, based on an active antenna concept and a direct matching technique. For exact circuit impedance, via holes are processed with precise fabrication techniques. The implemented circuit has achieved a circuit size reduction of 76.7%. The proposed system has been applied to a wireless wake-up receiver system with excellent operating performance.

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Visser, Hubregt J., Shady Keyrouz, and A. B. Smolders. "Optimized rectenna design." Wireless Power Transfer 2, no. 1 (February 10, 2015): 44–50. http://dx.doi.org/10.1017/wpt.2014.14.

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Design steps are outlined for maximizing the RF-to-dc power conversion efficiency (PCE) of a rectenna. It turns out that at a frequency of 868 MHz, a high-ohmic loaded rectifier will lead to a highly sensitive and power conversion efficient rectenna. It is demonstrated that a rectenna thus designed, using a 50 Ω antenna and lumped element matching network gives a superior PCE compared with state of the art also for lower resistive loading. By omitting the matching network and directly, conjugate impedance matching the antenna to the rectifier, the PCE may be further increased and the rectenna size reduced as it is demonstrated with a rectenna prototype measuring only 0.028 squared wavelengths at 868 MHz and demonstrating a PCE of 55% for a −10 dBm RF input power level.

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Ribate, Mohamed, Rachid Mandry, Jamal Zbitou, Larbi El Abdellaoui, Ahmed Errkik, Mohamed Latrach, and Ahmed Lakhssassi. "A trade-off design of microstrip broadband power amplifier for UHF applications." International Journal of Electrical and Computer Engineering (IJECE) 10, no. 1 (February 1, 2020): 919. http://dx.doi.org/10.11591/ijece.v10i1.pp919-927.

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In this paper, the design of a Broadband Power Amplifier for UHF applications is presented. The proposed BPA is based on ATF13876 Agilent active device. The biasing and matching networks both are implemented by using microstrip transmission lines. The input and output matching circuits are designed by combining two broadband matching techniques: a binomial multi-section quarter wave impedance transformer and an approximate transformation of previously designed lumped elements. The proposed BPA shows excellent performances in terms of impedance matching, power gain and unconditionally stability over the operating bandwidth ranging from 1.2 GHz to 3.3 GHz. At 2.2 GHz, the large signal simulation shows a saturated output power of 18.875 dBm with an output 1-dB compression point of 6.5 dBm of input level and a maximum PAE of 36.26%.

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Mo, Lingfei, and Chenyang Li. "Double Loop Inductive Feed Patch Antenna Design for Antimetal UHF RFID Tag." International Journal of Antennas and Propagation 2019 (March 21, 2019): 1–8. http://dx.doi.org/10.1155/2019/2917619.

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Planar UHF RFID antimetal tag can be widely used for the metallic products or packages with metal material inside. A double loop inductive feed planar patch antenna is proposed for UHF RFID tag mounted on metallic objects. Compared to conventional microstrip antennas or PIFA antennas used for UHF RFID tags, the double loop inductive feed patch antenna has a planar structure, with no short via or short wall, which could decrease the manufacturing cost of the tags. The double loop inductive feed structure also increases the radiation performance of the planar antenna. Moreover, the double loop inductive feed structure makes the impedance of the patch antenna be tuned easily for conjugate impedance matching.

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Bonenberger, Christopher M. A., and Klaus W. Kark. "A Broadband Impedance-Matching Method for Microstrip Patch Antennas Based on the Bode-Fano Theory." Frequenz 72, no. 7-8 (June 26, 2018): 373–80. http://dx.doi.org/10.1515/freq-2018-0037.

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Abstract Considering the narrow bandwidth of microstrip antennas, but also their applicability in upcoming technologies, this paper addresses the problem of wide-band matching, the theoretical bounds on the matching bandwidth and low-cost and low-complexity matching strategies. In this context the Bode-Fano bounds of single mode, linearly polarized aperture-coupled microstrip antennas is evaluated, optimized and compared to the theoretical bounds on matching bandwidth of other common feeding technologies. A detailed study of the input impedance of aperture-coupled patch antennas shows how to widen the Fano bounds. Based on this, a straight-forward and effective method to optimize the Fano bound is given. After optimization of the antennas input impedance, basic matching techniques can be applied, to exploit the enlarged bandwidth potential. As an example a $\lambda/4$-transformer as matching element is proposed. Design equations and simulation and measurement results of X-band prototypes are given as verification.

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Sanyal, Prof Judhajit, Prof Sandip Bhattacharya, Mr Prabal Chakraborty, and Ms Renaissa Das. "Comparison of Two Step and Six Step Impedance Matching Techniques using Quarter Wave Transformers." IJIREEICE 5, no. 2 (February 15, 2017): 15–17. http://dx.doi.org/10.17148/ijireeice.2017.5202.

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Pazouki, Hossien, and Mahdi Pirmoradian. "A Survey of Input Impedance Matching Circuit Design Techniques in Low Noise Amplifiers (LNAs)." Journal of Engineering Technology 6, no. 2 (December 10, 2016): 147–65. http://dx.doi.org/10.21859/jet-060213.

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Yee, Chang Fei, Muammar Mohamad Isa, Azremi Abdullah Al-Hadi, and Mohd Khairuddin Md Arshad. "Techniques of impedance matching for minimal PCB channel loss at 40 GBPS signal transmission." Circuit World 45, no. 3 (August 5, 2019): 132–40. http://dx.doi.org/10.1108/cw-01-2019-0004.

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Purpose This paper aims to analyze the negative impact of surface mount (SMT) pad and imperfect via structure such as stub, pad, non-functional pad (NFP) and anti-pad on the signal integrity at 40 Gbps transmission on printed circuit board (PCB) due to impedance mismatch or discontinuity. The optimized modeling of via and SMT structures is performed to achieve minimal impedance mismatch and insertion loss less than 10 dB for six-inch full path transmission line between transmitter and receiver on PCB at Nyquist frequency 20 GHz. Design/methodology/approach This work is split into two phases. The first phase involves optimization of via and SMT structures in three-dimensional electromagnetic (3DEM) simulation using Hyperlynx Via Wizard and Keysight EMPro software, respectively, followed by analysis of time domain reflectometry (TDR) and insertion loss (Sdd21). Whereas, in the second phase, full path hybrid mode simulation involving vias for signal layer transition, a 6-inch PCB channel and SMT pads is performed using Keysight ADS software to observe the TDR, Sdd21 and eye diagram at 40 Gbps transmission. Findings Imperfect via and SMT structures have a negative effect on signal reflection and attenuation. The optimized via and SMT minimizes the impedance mismatch by 81 per cent and insertion loss by 4.5 dB, ultimately enlarging the eye diagram opening to achieve minimal data loss at receiver with 40 Gbps transmission. Originality/value The results of original empirical research work on signal integrity analysis that optimizes the PCB channel design to achieve 40 Gbps signal transmission are presented in this study. It serves as a reference guide for high-speed PCB layout design.

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Vasjanov, Aleksandr, and Vaidotas Barzdenas. "A Methodology Improving Off-Chip, Lumped RF Impedance Matching Network Response Accuracy." Electronics 7, no. 9 (September 10, 2018): 188. http://dx.doi.org/10.3390/electronics7090188.

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Impedance matching is concurrent with any radio frequency (RF) circuit design and is essential for maximizing the gain and efficiency while minimizing the noise of high-frequency amplifiers as well as some mixer topologies. The main impedance matching network components are capacitors, inductors, and RF transformers all of which contain parasitic parameters that influence the matching response S11 curve. After calculating matching network component values using classical matching techniques, the measured and simulated response curves differ depending on the target frequency. This results in multiple calculations and measurement cycles in order to precisely match the source and load at the desired frequency. This article proposes an algorithm and methodology of estimating component parasitic parameters and taking them into account when calculating the main component parameters (capacitance and inductance). The proposed algorithm has been implemented as a toolbox in Cadence Virtuoso and verified through simulation and measurements. Measurement results show, that at 500 MHz 10% tolerance components with parasitics included and values based on classical theory provide a 3.2–9.8% offset from the target frequency. In the same conditions, matching networks with compensated (according to the proposed algorithm) values provide 0.1–8.8% target frequency offset. At 1500 MHz 10% components provided 4–12.3% (non-compensated) and 1–8.7% (compensated) target frequency offset ranges. At 3000 MHz. The frequency offset range of using compensated matching network component values is reduced from 5.5–15.1% to 1.3–8.1%.

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Galos, Richard, Yong Shi, Zhongjing Ren, Liang Zhou, Hao Sun, Xiaoyu Su, and Jianping Yuan. "Electrical Impedance Measurements of PZT Nanofiber Sensors." Journal of Nanomaterials 2017 (2017): 1–9. http://dx.doi.org/10.1155/2017/8275139.

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Electrical impedance measurements of PZT nanofiber sensors were performed using a variety of methods over a frequency spectrum ranging from DC to 1.8 GHz. The nanofibers formed by electrospinning with diameters ranging from 10 to 150 nm were collected and integrated into sensors using microfabrication techniques. Special matching circuits with ultrahigh input impedance were fabricated to produce low noise, measurable sensor outputs. Material properties including resistivity and dielectric constant are derived from the impedance measurements. The resulting material properties are also compared with those of individual nanofibers being tested using conductive AFM and Scanning Conductive Microscopy.

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Du, Yongqian, Wei Hu, Guifang Li, and Shibin Liu. "Modeling and Analysis of the Nonideality of LO Pulse Overlap for Multi-Phase Passive Mixer First RF Frontend." Journal of Circuits, Systems and Computers 28, no. 05 (May 2019): 1950086. http://dx.doi.org/10.1142/s0218126619500865.

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Multi-phase passive mixer (PM) first RF frontend has regained great concern for its satisfactory noise performance comparable to LNA-first frontend. Moreover, the re-configurable impedance, bi-directional signal transparency and bi-directional impedance translation performance enable a splendid application future for the multi-phase PM-first RF frontend. However, it still suffers from quite a few nonidealities, among which the adjacent Local Oscillator (LO) pulse overlap is the remaining nonideality lacking deep research, and how the LO pulse overlap decays the impedance matching and noise performance of multi-phase PM-first RF frontend remains unclear. In this work, an accurate model is, for the first time, established and analyzed to reveal how the LO pulse overlap decays the impedance matching and noise performance of multi-phase PM-first RF frontend. The analytical and simulation results demonstrate that the impedance matching will be drastically deteriorated because of LO overlap, and when LO pulse overlap exceeds 2% the impedance matching will be collapsed, while the noise figure (NF) is deteriorated by 3.1 dB when LO overlap ranges from 0% to 2%. Moreover, even a chocking inductor technique and a technique by introducing a synchronous phase-shifted signal have been proposed to suppress the LO overlap, the gain and noise performance can be deteriorated or the power and chip area cost are big. To address this question, a LO pulse overlap suppression technique is proposed furthermore by introducing an overlap safeguard factor (OLSF) in this work. The additional impedance smaller than 2[Formula: see text][Formula: see text] in the main signal path makes the OLSF scheme beneficial for noise and gain improvement, and the proposed OLSF scheme is power, area (0.04[Formula: see text]mm[Formula: see text] and cost efficient compared with existing LO overlap suppression techniques.

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Zhaksylyk, Yelzhas, Einar Halvorsen, Ulrik Hanke, and Mehdi Azadmehr. "Analysis of Fundamental Differences between Capacitive and Inductive Impedance Matching for Inductive Wireless Power Transfer." Electronics 9, no. 3 (March 13, 2020): 476. http://dx.doi.org/10.3390/electronics9030476.

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Inductive and capacitive impedance matching are two different techniques optimizing power transfer in magnetic resonance inductive wireless power transfer. Under ideal conditions, i.e., unrestricted parameter ranges and no loss, both approaches can provide the perfect match. Comparing these two techniques under non-ideal conditions, to explore fundamental differences in their performance, is a challenging task as the two techniques are fundamentally different in operation. In this paper, we accomplish such a comparison by determining matchable impedances achievable by these networks and visualizing them as regions of a Smith chart. The analysis is performed over realistic constraints on parameters of three different application cases both with and without loss accounted for. While the analysis confirms that it is possible to achieve unit power transfer efficiency with both approaches in the lossless case, we find that the impedance regions where this is possible, as visualized in the Smith chart, differ between the two approaches and between the applications. Furthermore, an analysis of the lossy case shows that the degradation of the power transfer efficiencies upon introduction of parasitic losses is similar for the two methods.

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Ndukwe, Cherechi, Oliver Ozioko, and Okere A. U. "Design and Fabrication of a 1.5GHz Microwave Low Noise Amplifier with Suitable Low-noise and High Gain Characteristics." European Journal of Engineering Research and Science 2, no. 8 (August 17, 2017): 7. http://dx.doi.org/10.24018/ejers.2017.2.8.425.

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This paper presents the design, simulation and fabrication of a low noise amplifier with high gain of 1.5GHz. In communication systems, there is always difficulty in distinguishing the received signal from noise at very low signal powers. A low noise amplifier (LNA) is an effective and low-cost way of enhancing this signal quality through signal amplification at the receiver. In this work, LNA simulation and a novel design was carried out using the N76038A field effect transistor (FET). To ensure it is stable over a wide range of frequencies, the input and output stability of the transistor were plotted over its operating frequencies (0.1 GHz to 18 GHz). Constant gain and noise figure circles were plotted and the source impedance properly chosen. The input network was matched to the source impedance and conjugate matching used to match the output. The schematic was converted to microstrip and produced on a printed circuit board. Testing was carried out using the vector network analyser (VNA) and matching errors then corrected by calibration process. The fabricated LNA has a gain of 13.76dB and noise figure of 1.57dB which is in close agreement with a simulation result of 14.25dB and 1.56dB respectively.

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Kim, Bo Su, Jae-Hoon Ji, Hong-Tae Kim, Sung-Jin Kim, and Jung-Hyuk Koh. "Improved Multilayered (Bi,Sc)O3-(Pb,Ti)O3 Piezoelectric Energy Harvesters Based on Impedance Matching Technique." Sensors 20, no. 7 (March 31, 2020): 1958. http://dx.doi.org/10.3390/s20071958.

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As a piezoelectric material, (Bi,Sc)O3-(Pb,Ti)O3 ceramics have been tested and analyzed for sensors and energy harvester applications owing to their relatively high Curie temperature and high piezoelectric coefficient. In this work, we prepared optimized (Bi,Sc)O3-(Pb,Ti)O3 piezoelectric materials through the conventional ceramic process. To increase the output energy, a multilayered structure was proposed and designed, and to obtain the maximum output energy, impedance matching techniques were considered and tested. By varying and measuring the energy harvesting system, we confirmed that the output energies were optimized by varying the load resistance. As the load resistance increased, the output voltage became saturated. Then, we calculated the optimized output power using the electric energy formula. Consequently, we identified the highest output energy of 5.93 µW/cm2 at 3 MΩ for the quadruple-layer harvester and load resistor using the impedance matching system. We characterized and improved the electrical properties of the piezoelectric energy harvesters by introducing impedance matching and performing the modeling of the energy harvesting component. Modeling was conducted for the piezoelectric generator component by introducing the mechanical force dependent voltage sources and load resistors and piezoelectric capacitor connected in parallel. Moreover, the generated output voltages were simulated by introducing an impedance matching technique. This work is designed to explain the modeling of piezoelectric energy harvesters. In this model, the relationship between applied mechanical force and output energy was discussed by employing experimental results and simulation.

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Evseev, Vladimir, Mikhail Ivlev, Elena Lupanova, Sergey Nikulin, Vitaliy Petrov, and Andrey Terentyev. "Automation of S-parameters measurements of high-power microwave transistors in a contact device with tunable strip matching circuits." ITM Web of Conferences 30 (2019): 11002. http://dx.doi.org/10.1051/itmconf/20193011002.

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In the practice by microwave power transistor amplifiers developing, the variable load method is usually used to determine the impedances of matching circuits in the complex conjugate matching mode. This solution involves the use of expensive equipment - coaxial impedance tuners and contact devices for mounting transistors in low impedance strip lines. An even more complicated and expensive way is the concept of X- parameters, based on the use of unique measuring equipment - a non-linear vector network analyzer, and a simulator for non-linear circuits design. The article proposes an alternative solution adapted to the operation of the transistor in real conditions and allowing to design the output stages of microwave power amplifiers using analysis and optimization of linear electrical circuits. The essence of the proposed solution is to automate the measurement of non-linear S-parameters of high-power microwave transistors in a contact device with tunable strip matching circuits for various DC supply voltage, frequency and input power mode in case of continuous or pulse input signal. The nonlinear S-parameters of the contact device are measured using the method of spatially remote variable load in the frequency range, in which the line conditioning and the maximum output power are achieved. The minimum of the reflected wave amplitude and the maximum gain are reached using movable strip matching transformers. The S-parameters measured in the coaxial line are automatically recalculated to the physical boundaries of the transistor by registering the positions of the input and output strip transformers.

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Cheng, Hesheng, Jin Zhang, Hexia Cheng, and Qunli Zhao. "Compact Design of Circularly Polarized Antenna with Vertical Slotted Ground for RFID Reader Application." Journal of Electrical and Computer Engineering 2017 (2017): 1–5. http://dx.doi.org/10.1155/2017/1936849.

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A novel compact circular polarization (CP) microstrip antenna is proposed for UHF ultrahigh frequency (UHF) radio frequency identification (RFID) reader applications. The proposed antenna is composed of a corner truncated square-ring radiating patch on a substrate and a vertical slotted ground surrounding four sides of the antenna. A new feeding scheme is designed from flexible impedance matching techniques. The impedance bandwidths for S11<-10 dB and 3 dB axial ratio (AR) bandwidth are 12.1% (794.5–896.5 MHz) and 2.5% (833.5–854.5 MHz), respectively.

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Liao, Yi, Yuan Zhang, Kun Cai, and Wei Gao. "A Simple Equivalent Circuit for Small RFID Tag Antennas in Low Loss Dielectric Materials." Applied Mechanics and Materials 433-435 (October 2013): 1470–73. http://dx.doi.org/10.4028/www.scientific.net/amm.433-435.1470.

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Small radio frequency identification (RFID) tag antennas are generally designed to achieve conjugate matching with capacitive chips at the called tag resonant frequency. An approximate equivalent circuit is proposed to represent the antenna input impedance in low loss dielectric materials. It consists of a shunt conductance considered to be linearly proportional to loss tangent, an input resistance and reactance of antenna in lossless materials. Comparing with the simulated result of full wave numerical tool, the equivalent circuit gives acceptable errors in input resistance and reactance at the tag resonant frequency and nearby. The simple equivalent circuit can be used to reduce the repetitive simulation work for different loss tangent.

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Rahman, Akhlaq, and Fred Olinger. "Improvement of Rated Power and VSWR Characteristics for Termination Resistor with Integrated Matching Network and Efficient Thermal Management." International Symposium on Microelectronics 2011, no. 1 (January 1, 2011): 000318–21. http://dx.doi.org/10.4071/isom-2011-tp3-paper6.

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Matching RF and Microwave signals to components within a circuit has become more challenging for circuit designer as operating frequency and power handling requirement increase. Termination resistors with excellent power handling capability with superior voltage standing wave ratio (VSWR) characteristics are needed for microwave circuit components in various wireless and telecommunication application. In this work, we extensively studied to improve the power handling capability and VSWR of termination resistor while maintaining the smaller size. We optimized the energy transmission within the component and significantly improved the efficiency of energy transfer between the transmission lines and the terminations. We discussed techniques of improving power handling capability and reduction of thermal fatigue to the component’s structure. By using innovative techniques of heat transfer we appreciably increased power handling capability while keeping the product size as minimum. We constructed matching network using integrated microstrip line at the beginning of the resistor material. We optimized impedance matching by varying length, width and pattern of transmission line as well as using defective ground structure (DGS) technique. We minimized the detrimental influence of component footprint and resistor material characteristics effect on signal reflection. Considering the necessary microwave parameters and required thermal performance, we designed and manufactured Pb free high power termination resistor. Several sizes of resistor are manufactured with rated power of 20 Watt, and 100 Watt which provides excellent VSWR characteristics for frequency up to 4 GHz. Resistors are manufactured for 50 ohm impedance; however, methods mentioned in the study are applicable to any impedance.

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Couraud, Benoit, Remy Vauche, Spyridon Nektarios Daskalakis, David Flynn, Thibaut Deleruyelle, Edith Kussener, and Stylianos Assimonis. "Internet of Things: A Review on Theory Based Impedance Matching Techniques for Energy Efficient RF Systems." Journal of Low Power Electronics and Applications 11, no. 2 (March 31, 2021): 16. http://dx.doi.org/10.3390/jlpea11020016.

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Within an increasingly connected world, the exponential growth in the deployment of Internet of Things (IoT) applications presents a significant challenge in power and data transfer optimisation. Currently, the maximization of Radio Frequency (RF) system power gain depends on the design of efficient, commercial chips, and on the integration of these chips by using complex RF simulations to verify bespoke configurations. However, even if a standard 50Ω transmitter’s chip has an efficiency of 90%, the overall power efficiency of the RF system can be reduced by 10% if coupled with a standard antenna of 72Ω. Hence, it is necessary for scalable IoT networks to have optimal RF system design for every transceiver: for example, impedance mismatching between a transmitter’s antenna and chip leads to a significant reduction of the corresponding RF system’s overall power efficiency. This work presents a versatile design framework, based on well-known theoretical methods (i.e., transducer gain, power wave approach, transmission line theory), for the optimal design in terms of power delivered to a load of a typical RF system, which consists of an antenna, a matching network, a load (e.g., integrated circuit) and transmission lines which connect all these parts. The aim of this design framework is not only to reduce the computational effort needed for the design and prototyping of power efficient RF systems, but also to increase the accuracy of the analysis, based on the explanatory analysis within our design framework. Simulated and measured results verify the accuracy of this proposed design framework over a 0–4 GHz spectrum. Finally, a case study based on the design of an RF system for Bluetooth applications demonstrates the benefits of this RF design framework.

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Koziel, Slawomir, and Adrian Bekasiewicz. "On deterministic procedures for low-cost multi-objective design optimization of miniaturized impedance matching transformers." Engineering Computations 34, no. 2 (April 18, 2017): 403–19. http://dx.doi.org/10.1108/ec-01-2016-0046.

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Purpose This paper aims to investigate deterministic strategies for low-cost multi-objective design optimization of compact microwave structures, specifically, impedance matching transformers. The considered methods involve surrogate modeling techniques and variable-fidelity electromagnetic (EM) simulations. In contrary to majority of conventional approaches, they do not rely on population-based metaheuristics, which permit lowering the design cost and improve reliability. Design/methodology/approach There are two algorithmic frameworks presented, both fully deterministic. The first algorithm involves creating a path covering the Pareto front and arranged as a sequence of patches relocated in the course of optimization. Response correction techniques are used to find the Pareto front representation at the high-fidelity EM simulation level. The second algorithm exploits Pareto front exploration where subsequent Pareto-optimal designs are obtained by moving along the front by means of solving appropriately defined local constrained optimization problems. Numerical case studies are provided demonstrating feasibility of solving real-world problems involving expensive EM-simulation models of impedance transformer structures. Findings It is possible, by means of combining surrogate modeling techniques and constrained local optimization, to identify the set of alternative designs representing Pareto-optimal solutions, in a realistic time frame corresponding to a few dozen of high-fidelity EM simulations of the respective structures. Multi-objective optimization for the considered class of structures can be realized using deterministic approaches without defaulting to evolutionary methods. Research limitations/implications The present study can be considered a step toward further studies on expedited optimization of computationally expensive simulation models for miniaturized microwave components. Originality/value The proposed algorithmic solutions proved useful for expedited multi-objective design optimization of miniaturized microwave structures. The problem is extremely challenging when using conventional methods, in particular evolutionary algorithms. To the authors’ knowledge, this is one of the first attempts to investigate deterministic surrogate-assisted multi-objective optimization of compact components at the EM-simulation level.

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Berrich, Loubna, and Lahbib Zenkouar. "Microruban Dipole Antenna for RFID Applications at 2.45 GHz." International Journal of Electrical and Computer Engineering (IJECE) 6, no. 6 (December 1, 2016): 2891. http://dx.doi.org/10.11591/ijece.v6i6.11408.

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Radio Frequency Identification (RFID) is a technology used mainly to identify tagged items or to track their locations. The most used antennas for RFID application are planar dipoles. For antenna design, it is necessary that the antenna has an impedance value equal to the conjugate of the impedance of the integrated circuit CI. To have a good adaptation allowing the maximum power transfer, there are several techniques. In this work we focus to the adaptation technical T-match which is based on the insertion of a second folded dipole in the center of the first dipole. This technique is modeled by an equivalent circuit to calculate the size of the folded dipole to have new input impedance of the antenna equal to the conjugate of the impedance of the IC. We also look to present a conceptual and technological approach of new topologies of linear dipoles. We proceeded to fold at right angles of the radiating strands in order to explore other topologiesof type L and Z. The interest of this microstrip folded dipole is their effectiveness to achieve coverage of Blind directions. The results obtained by the platform Ansoft HFSS, allowed us to obtain a quasi-uniform radiation patterns and the reflection coefficients that exceed -37 dB.

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Berrich, Loubna, and Lahbib Zenkouar. "Microruban Dipole Antenna for RFID Applications at 2.45 GHz." International Journal of Electrical and Computer Engineering (IJECE) 6, no. 6 (December 1, 2016): 2891. http://dx.doi.org/10.11591/ijece.v6i6.pp2891-2899.

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Radio Frequency Identification (RFID) is a technology used mainly to identify tagged items or to track their locations. The most used antennas for RFID application are planar dipoles. For antenna design, it is necessary that the antenna has an impedance value equal to the conjugate of the impedance of the integrated circuit CI. To have a good adaptation allowing the maximum power transfer, there are several techniques. In this work we focus to the adaptation technical T-match which is based on the insertion of a second folded dipole in the center of the first dipole. This technique is modeled by an equivalent circuit to calculate the size of the folded dipole to have new input impedance of the antenna equal to the conjugate of the impedance of the IC. We also look to present a conceptual and technological approach of new topologies of linear dipoles. We proceeded to fold at right angles of the radiating strands in order to explore other topologiesof type L and Z. The interest of this microstrip folded dipole is their effectiveness to achieve coverage of Blind directions. The results obtained by the platform Ansoft HFSS, allowed us to obtain a quasi-uniform radiation patterns and the reflection coefficients that exceed -37 dB.

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Zhang, Jie, Randall L. Mackie, and Theodore R. Madden. "3-D resistivity forward modeling and inversion using conjugate gradients." GEOPHYSICS 60, no. 5 (September 1995): 1313–25. http://dx.doi.org/10.1190/1.1443868.

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We have developed rapid 3-D dc resistivity forward modeling and inversion algorithms that use conjugate gradient relaxation techniques. In the forward network modeling calculation, an incomplete Cholesky decomposition for preconditioning and sparse matrix routines combine to produce a fast and efficient algorithm (approximately 2 minutes CPU time on a Sun SPARC‐station 2 for 50 × 50 × 20 blocks). The side and bottom boundary conditions are scaled impedance conditions that take into account the local current flow at the boundaries as a result of any configuration of current sources. For the inversion, conjugate gradient relaxation is used to solve the maximum likelihood inverse equations. Since conjugate gradient techniques only require the results of the sensitivity matrix [Formula: see text] or its transpose [Formula: see text] multiplying a vector, we are able to bypass the actual computation of the sensitivity matrix and the inversion of [Formula: see text], thus greatly decreasing the time needed to do 3-D inversions. We demonstrate 3-D resistivity tomographic imaging using pole‐pole resistivity data collected during an experiment for a leakage monitoring system near evaporation ponds at the Mojave Generating Station in Laughlin, Nevada.

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Bader, Sean, Xinming Wu, and Sergey Fomel. "Missing log data interpolation and semiautomatic seismic well ties using data matching techniques." Interpretation 7, no. 2 (May 1, 2019): T347—T361. http://dx.doi.org/10.1190/int-2018-0044.1.

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Relating well-log data, measured in depth, to seismic data, measured in time, typically requires estimating well-log impedance and a time-to-depth relationship using available sonic and density logs. When sonic and density logs are not available, it is challenging to incorporate wells into integrated reservoir studies because the wells cannot be tied to seismic. We have developed a workflow to estimate missing well-log information, automatically tie wells to seismic data, and generate a global well-log property volume using data matching techniques. We first used the local similarity scan to align all logs to constant geologic time and interpolate missing well-log information. Local similarity is then used to tie available wells with seismic data. Finally, log data from each well are interpolated along local seismic structures to generate global log property volumes. We use blind well tests to verify the accuracy of well-log interpolation and seismic well ties. Applying our workflow to a 3D seismic data set with 26 wells achieves consistent and verifiably accurate results.

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Illahi, U., J. Iqbal, M. I. Sulaiman, M. Alam, M. S. Mazliham, and M. H. Jamaluddin. "Circularly polarized rectangular dielectric resonator antenna excited by an off-set conformal metal strip." Indonesian Journal of Electrical Engineering and Computer Science 15, no. 2 (August 1, 2019): 902. http://dx.doi.org/10.11591/ijeecs.v15.i2.pp902-909.

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A rectangular dielectric resonator antenna (DRA) has been excited by an off-set single conformal metal strip. By using such excitation technique two degenerate resonant modes, TExδ11 and TEy1δ1 of the rectangular DRA have been excited to achieve circular polarization (CP). A CP bandwidth of ~ 5.2% in conjunction with a wide impedance matching bandwidth of ~ 54% has been provided by the proposed DRA configuration. The antenna design has been simulated using computer simulation technology (CST). Antenna prototype has been built to verify the impedance matching bandwidth. Far field parameters have been optimized and verified using two simulation techniques in CST i.e. finite integration technique (FIT) and finite element method (FEM). A good agreement between the simulated and measured result has been observed for S11. Similarly a very good resemblance between the far field results from FIT and FEM have been demonstrated.

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Shafique, Rabia, Kelash Kanwar, Fida Hussain, Ruben Morales Menendez, Mohammad Khubeb Siddiqui, Haris Jawad Arain, and Monica Mehrotra. "Comparison of different feeding techniques for a patch antenna at an X frequency band to evaluate its quantitative impact on the antenna’s parameters." Journal of Applied Research and Technology 18, no. 6 (December 31, 2020): 341–61. http://dx.doi.org/10.22201/icat.24486736e.2020.18.6.1350.

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In this paper, the comparison of different feeding techniques for a patch antenna, at X frequency band, to evaluate its quantitative impact on the different antenna parameters is presented. When different feeding techniques are applied at the X band spectrum to improve the impedance matching the performance of various characteristics parameters such as radiation pattern, gain, beam width etc are influenced. To find how much these are influenced a comparative analysis is carried out and results are presented in this paper. For investigation purpose, the patch antenna and the various feeding techniques were designed on Roger (RT5880) substrate at 8 GHz resonating frequency.

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Ribate, Mohamed, Rachid Mandry, Jamal Zbitou, Larbi El Abdellaoui, Ahmed Errkik, Mohamed Latrach, and Ahmed Lakhssassi. "Design of L-S band broadband power amplifier using microstip lines." International Journal of Electrical and Computer Engineering (IJECE) 10, no. 5 (October 1, 2020): 5400. http://dx.doi.org/10.11591/ijece.v10i5.pp5400-5408.

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This contribution introduces a novel broadband power amplifier design, operating in the frequency band ranging from 1.5 GHz to 3 GHz which cover the mainstream applications running in L and S bands. Both matching and biasing networks are synthesized by using microstrip transmission lines. In order to provide a wide bandwidth, two broadband matching techniques are deployed for this purpose, the first technique is an approximate transformation of a previously designed lumped elements matching networks into microstrip matching circuits, and the second technique is a binomial multi-sections quarter wave impedance transformer. The proposed work is based on ATF-13786 active device. The simulation results depict a maximum power gain of 16.40 dB with an excellent input and output matching across 1.5 GHz ~ 3 GHz. At 2.2 GHz, the introduced BPA achieves a saturated output power of 16.26 dBm with a PAE of 21.74%, and a 1-dB compression point of 4.5 dBm input power level. The whole circuitry is unconditionally stable over the overall bandwidth. By considering the broadband matching, the proposed design compares positively with the most recently published BPA.

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Krukonis, Audrius, and Šarūnas Mikučionis. "THE FREQUENCY CHARACTERISTICS OF COUPLED MICROSTRIP LINES / SUSIETŲJŲ MIKROJUOSTELINIŲ LINIJŲ DAŽNINĖS CHARAKTERISTIKOS." Mokslas - Lietuvos ateitis 5, no. 2 (May 24, 2013): 173–80. http://dx.doi.org/10.3846/mla.2013.33.

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The article deals with the use of the finite difference time domain method and uniaxial perfectly matching layer for analysis of frequency characteristics of coupled microstrip transmission lines. It describes calculation techniques for voltage, current, characteristic impedance and effective dielectric constant of each signal conductor. Besides, it analyses the frequency dependencies of characteristic impedance and the effective dielectric constant. Article in Lithuanian. Santrauka Straipsnyje aptariamas baigtinių skirtumų laiko srities metodo taikymas ir absorbuojančio sluoksnio taikymas susietųjų mikrojuostelinių linijų analizei. Sudaryti ir išnagrinėti baigtinių skirtumų laiko srities metodu grįsti susietųjų mikrojuostelinių linijų matematiniai modeliai. Pateikiamos kiekvieno iš laidininkų įtampos, srovės, charakteringojo impedanso ir efektyviosios dielektrinės skvarbos skaičiavimo metodikos. Aptariami skaičiavimo metodikų pranašumai, trūkumai, pateikiamos jų tobulinimo kryptys.

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Abu-Taha, Jawdat Y., and Metin Yazgi. "Improving the bandwidth of the transimpedance amplifier based on CS stages in cascode configuration using impedance matching techniques." Analog Integrated Circuits and Signal Processing 89, no. 3 (May 17, 2016): 685–91. http://dx.doi.org/10.1007/s10470-016-0757-6.

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Macfarlane, JC, LB Whitbourn, and RA Batchelor. "Experimental Study of Noise Temperature and Conversion Loss of SIS Junction Mixers." Australian Journal of Physics 39, no. 3 (1986): 379. http://dx.doi.org/10.1071/ph860379.

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Experiments on the performance of superconductor-insulator-superconductor (SIS) tunnel junctions as heterodyne mixers at 40 GHz are reported. The techniques developed for the fabrication of multi-junction SIS series arrays differ from, and are considerably simpler than, other methods described in the literature. Results are reported on mixer noise temperature, conversion loss, saturation, local oscillator power levels and mixer dynamic range. Factors affecting the mixer's conversion performance are identified and comparisons are made with other reported results. It is concluded that mixer performance in the present experiments is limited by imperfect impedance matching at the signal frequency, due to relatively large values of parasitic capacitance in the junctions. Future work is aimed at both reducing the junction capacitance and redesigning the mixer mount to give improved r.f. matching.

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Bauer, Maris, Sebastian Boppel, Jingshui Zhang, Adam Rämer, Serguei Chevtchenko, Alvydas Lisauskas, Wolfgang Heinrich, Viktor Krozer, and Hartmut G. Roskos. "Optimization of the Design of Terahertz Detectors Based on Si CMOS and AlGaN/GaN Field-Effect Transistors." International Journal of High Speed Electronics and Systems 25, no. 03n04 (September 2016): 1640013. http://dx.doi.org/10.1142/s0129156416400139.

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TeraFETs are THz power detectors based on field-effect transistors (FETs) integrated with antennas. The first part of this paper discusses the design of Si CMOS TeraFETs leading to an optimized noise-equivalent power close to the room-temperature limit. The impact of the choice of the gate width and gate length, the role of the parasitic effects associated with the technology node, and the conjugate matching of antenna and FET impedance – which is possible over narrow THz frequency bands because of the frequency dependence of the channel impedance resulting from plasmonic effects – are highlighted. Taking these aspects into account, we implement narrow-band detectors of two different designs. Using a 90-nm and a 65-nm CMOS technology, we reach a room-temperature cross-sectional NEP of 10 pW/√Hz at 0.63 THz. We then explore the optimization of AlGaN/GaN TeraFETs equipped with broadband antennae. A room-temperature optical NEP of 26 pW/√Hz is achieved around 0.5 THz despite the fact that the existence of pronounced ungated regions leads to a significant hot-electron thermoelectric DC voltage reducing the rectified signal. AlGaN/GaN TeraFETs become competitive and they have the added advantage that they are extraordinarily robust against electrostatic shock even without inclusion of protection diodes into the design.

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Zhang, Guiheng, Wei Zhang, and Jun Fu. "Design of 85 GHz High Power Gain SiGe Buffer with Transformer Matching Network." Journal of Circuits, Systems and Computers 28, no. 07 (June 27, 2019): 1950114. http://dx.doi.org/10.1142/s0218126619501147.

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An 85[Formula: see text]GHz buffer with high power gain is shown in this paper. In order to obtain high power gain, two classic techniques to improve power gain are adopted. The first one is cascade structure of two power stages, and the other one is that each stage utilizes differential cascode structure. Meanwhile, the step-by-step pre-matching technique is applied to optimize the performance of buffer. The stability factor and output power are both improved with other critical design strategies, and a tradeoff is made between gain and efficiency. What’s more, single-ended transformer matching network (TMN) is applied to simplify matching method. The simplified matching method is easy to use with smith chart and works very well, then a modified transformer model is adopted to analyze and optimize the performance of TMN with iterations of impedance matching. After fabricated by 0.13[Formula: see text][Formula: see text]m SiGe BiCMOS technology, the buffer shows 18.5[Formula: see text]dB power gain and 2[Formula: see text]dBm output power of 1[Formula: see text]dB gain compression point with 2.8[Formula: see text]V supply voltage and 40[Formula: see text]mA operating current, and the saturated output power is 6.33[Formula: see text]dBm.

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Journal articles on the topic 'Conjugate Impedance Matching Techniques'

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