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We present an analytical model of the 2-D/3-D spreading of dc and small-signal minority carrier flow in forward-biased shallow finite-sized p-n junctions. The model achieves an analytical solution of the 2-D/3-D continuity equation by replacing a Dirichlet-Neumann mixed boundary condition by a Neumann condition. It expresses the current spreading in terms of the junction width, lateral (vertical) extent beyond the junction, diffusion length, lifetime, transit time, and frequency. It predicts that the small-signal spread of the minority carrier flow gets progressively restricted for frequencies greater than inverse lifetime in long diodes and inverse transit time in short diodes, at high frequencies, the minority carrier flow picture consists of a 1-D small-signal flow superposed over a 2-D/3-D dc flow. Under dc conditions, the flow is almost 1-D in short diodes, spreads with an increase in vertical extent, and saturates in long diodes. We give the critical lateral extent beyond which the spread saturates, in terms of the vertical extent. Our model includes a small-signal equivalent circuit, which considers both minority and majority carrier current spreading, the latter is frequency independent and becomes important at higher frequencies. We validate the model against numerical simulations, and show its application to a rectangular junction with rounded corners. � 2014 IEEE.

A damage identification method is proposed to identify the damage style and the damage parameters. By driving a pair of PZT patches out phase and in phase, the electric admittance of the PZT is obtained. The damage parameters are then identified from the changes of the admittance spectra caused by the appearance of damage. By comparing the identification result, the damage style can be determined and the damage parameters can be obtained. The middle basic particle swarm optimization algorithm is employed as a global search technique to back-calculate the damage. Experiments are carried out on beams. The results demonstrate that the proposed method is able to identify the damage style, and can effectively and reliably locate and quantify the damage in the beam.

Single molecule conductance measurements are often interpreted through computational modeling, but the complexity of these calculations makes it difficult to directly link them to simpler concepts and models. Previous work has attempted to make this connection using maximally localized Wannier functions and symmetry adapted basis sets, but their use can be ambiguous and non-trivial. Starting from a Hamiltonian and overlap matrix written in a hydrogen-like basis set, we demonstrate a simple approach to obtain a new basis set that is chemically more intuitive and allows interpretation in terms of simple concepts and models. By diagonalizing the Hamiltonians corresponding to each atom in the molecule, we obtain a basis set that can be partitioned into pseudo-σ and −π and allows partitioning of the Landuaer-Buttiker transmission as well as create simple Huckel models that reproduce the key features of the full calculation. This method provides a link between complex calculations and simple concepts and models to provide intuition or extract parameters for more complex model systems.

Since piezoelectric materials exhibit strong temperature dependency. The change of temperature results in marked variation of the PZT transducer’s electric impedance signals, which may lead to misjudgment of the structural health condition. A experiment was implemented on smart aggregates with embedded PZT transducers under 35°C, 45°C and 55°C three working conditions, and found that the temperature had significant influence on the electric admittance signals of embedded PZT transducers. The peak magnitudes of the admittance curves changed and the curves shifted leftward. Then a temperature compensation technique was used to minimize the temperature effects.

The paper investigates the applicability of some closed form expressions for the ground impedance and ground admittance of buried horizontal wires (bare and insulated) for lightning or switching transient analyses based on transmission line (TL) theory. In view of the frequency contents that typically characterize such transients, the behavior of the ground impedance and admittance is studied for a wide frequency range up to 10 MHz. Low frequency approximation of the ground impedance is not always appropriate for transient analysis. Sensitivity analyses show that, unlike overhead wires, the ground impedance for buried wires is little sensitive to the ground conductivity. On the other hand, the ground admittance varies strongly with the ground conductivity. The paper also discusses the results of transient analysis of buried cables performed by means of electromagnetic transient programs (EMTP) that neglect the ground admittance. The limits of such an approximation are discussed in order to evaluate the applicability of EMTP-like programs to the transient analysis of buried conductors. Transient pulse propagation in time domain based on finite difference time domain (FDTD) method of solution of TL equations is also discussed for a future inclusion of non-linear phenomena, like soil ionization and arcing/breakdown mechanisms, in the soil. The analysis presented could be useful in estimating surge propagation characteristics of buried wires for appropriate insulation coordination and transient protection. © 2007 IEEE.

A model for discharge lamp based on lamp electrical conductance is proposed. Physical assumptions are used to obtain this model. The model allows simulating lamp behavior at different frequencies and delivered power levels. The model has been verified using a high pressure sodium lamp supplied at 50 and 100kHz

Le present document traite de la mesure de l’impedance de transfert et des tensions de paradiaphonie d’un câble multifilaire blinde par un banc de mesure a structure triaxiale. Comme les elements theoriques de la premiere partie le justifient, nous montrons que les conducteurs interieurs au blindage vont jouer un role determinant sur l’amplitude des tensions parasites qui prennent naissance aux extremites du câble. Nous montrons egalement que lorsque se manifeste le couplage par conduction c’est a dire par la capacite de transfert du blindage, on ne peut plus negliger la reaction des conducteurs interieurs sur l’exterieur.

This paper deals with the calculation of a sparse network equivalent (SNE) for the analysis of electromagnetic transients in large systems. The methodology and the mathematical details are presented in the companion paper . This sequel presents application examples to demonstrate the accuracy and computational efficiency of the SNE. Equivalents for networks composed of 12, 50, and 100 transmission lines are derived and the results are discussed.

Arrays of voltage-controlled oscillators can be coupled by means of a network so as to be mutually injection locked and thus oscillate as an ensemble. This ensemble may be used to excite the elements of a phased array antenna in such a manner as to radiate an agile beam. Design of the coupling network requires attention to three key parameters: the inter-oscillator coupling strength, the network bandwidth, and the oscillator loading. These parameters can be related to the network admittance matrix elements, which, in turn, are related to the lumped element values. This provides convenient formulas for use in designing networks, which provide the necessary values of the above three key design parameters.

This paper analyzes stationary overvoltages in Petersen grounded systems resulting from a broken phase conductor. The analysis is done with basis in a real case where the overvoltages caused extensive damages and outages. It is shown that a requirement for high overvoltages to result is the combination of the following: The fault occurs on a radial connection that has substantial generation on one side only, the total compensation is close to 100%, and the compensation of the two subnetworks defined by the fault is far from 100% (one subnetwork is undercompensated and the other is overcompensated). These conditions were all met for the network subject to investigation. Overvoltages calculated by a simple model compare favorably with recorded results. The overvoltages are shown to be strongly dependent on the compensation level, the compensation distribution, and the shunt conductance to ground, and the load. A least squares method has been developed for estimating the shunt conductance based on a measured resonance curve.

Deposition of SrTiO3 (STO) thin films by ultra-high vacuum rf magnetron sputtering was performed in order to produce high-quality STO/p-Si (1 0 0) interfaces and STO insulator layers with high diel ...

In0.53Ga0.47As metal-oxide-semiconductor (MOS) capacitors with an Al2O3 gate oxide and a range of n and p-type In0.53Ga0.47As epitaxial concentrations were examined. Multi-frequency capacitance-voltage and conductance-voltage characterization exhibited minority carrier responses consistent with surface inversion. The measured minimum capacitance at high frequency (1 MHz) was in excellent agreement with the theoretical minimum capacitance calculated assuming an inverted surface. Minority carrier generation lifetimes, sg, extracted from experimentally measured transition frequencies, xm, using physics based a.c. simulations, demonstrated a reduction in sg with increasing epitaxial doping concentration. The frequency scaled conductance, G/x, in strong inversion allowed the estimation of accurate Cox values for these MOS devices.

This paper presents a new and simple compact model for the intrinsic metal oxide semiconductor (MOS) transistor, which accurately takes into account the non quasistatic (NQS) effects. This is done without any additional assumption or simplification than those required in the derivation of the classical description of the MOS channel charge. Moreover, the model is valid from weak to strong inversion and nonsaturation to saturation. The theoretical results are in very good agreement with measured data performed on devices of various channel length, from 300 /spl mu/m down to 0.5 /spl mu/m, and in various modes of operation.

This paper presents a method for the analysis of arbitrary shape and composition posts in a waveguide. The method segments the problem into regions that are characterized by their generalized admittance matrices. Both an analytical formulation and a boundary integral formulation based on homogeneous wave equation solutions are used in this characterization. Our method is especially fast and suitable for real time computer-aided design tools because only the changing parameters would have to be computed in a design process. This method also makes a simple combination of different numerical techniques possible.

L'anodisation du tantale en milieu aqueux a ete realisee par chronopotentiometrie. L'exploitation des diagrammes d'admittance permet d'acceder aux proprietes electriques de la couche d'oxyde formee. L'interface electrode/electrolyte peut etre modelisee par un circuit equivalent comportant une resistance R p en parallele avec une capacite C p , cette boucle etant elle-meme en serie avec une resistance R s . Les resultats ont montre l'influence du choix de l'electrolyte sur les proprietes electriques des couches d'oxyde formees. Dans un milieu donne, le produit R p .C p est constant pour une large gamme d'epaisseurs. La valeur de ce produit constitue un critere de qualite des couches formees; une valeur elevee indique que le transfert electronique a travers la couche d'oxyde est difficile, donc un caractere passivant plus marque.

A novel model-based sensorless-input current controller for three-phase active rectifiers is presented. The proposed algorithm is based upon a load-conductance rectifier controller, which was previously implemented using current sensors. The paper presents analytical studies and simulation results and discusses a simple implementation using a low cost integrated microcontroller. Experimental verification utilizes an active input/output insulated gate bipolar transistor (IGBT) converter. Simulation and experimental results for the proposed controller are compared to that of the sensor-based version to validate the efficacy of this novel algorithm.

In this work the back bias influence on the analog performance of tunnel-FETs is evaluated experimentally for the first time. The analysis of the transconductance, output conductance and intrinsic voltage gain (Av) was performed by comparing the pTFET behavior with a well-known pFinFET that was fabricated using the same process flow. Numerical simulations were also performed in order to explain the pTFET behavior. Although the pTFET shows to be more susceptible to the back bias condition, it also shows to present always a better Av for all bias conditions. The best result in both devices was obtained when the back bias is near 0 V and the Av difference is around 30 dB in favor of pTFET.

The dynamic load structure for symmetrical differential stages based on principle of self-compensation of active elements small-signal parameters influence on common-mode rejection ratio (CMR) is proposed. Shown that this load in traditional stage structure allows to decrease influence of active elements transfer conductance on CMR. Limiting estimations that characterize CMR maximum are found. Results of simulation and comparative research of different symmetrical differential stages are given. Shown that different circuit approaches for CMR optimization are consistent.

We propose a theory for stability analysis of railway systems based on energy exchange principles between the infrastructure and rolling stock. We show that if the rolling stock and infrastructure is dissipative with respect to specially constructed power functions (more general than voltage× current) stability is guaranteed. We thereby provide a proof of the Input Admittance Criterion (IAC) - a widely used empirical criterion in the railway industry - as special case of our results. Application of the theory is demonstrated with an example from a metro train system.

Renewable energy source is an echo friendly source of electrical energy. This paper develops a maximum power point tracker (MPPT) for optimizing the power output from any source under varying load condition. Simulations are carried out in MATLAB using Perturb and observe algorithm and incremental conductance algorithm and results compared.

This paper presents a comparative study between two maximum power point tracking (MPPT) methods in Matlab/Simulink program that are perturb-and-observe method and incremental conductance method. Starting from the implemented model of the photovoltaic (PV) array together with the buck converter and its MPPT control have been simulated the PV systems with both MPPT algorithms at different solar radiation and temperature, and finally are presented the simulations result depending on irradiance and temperature.

This article evaluates the characteristics of a proposed π-CLCL immittance converter, which is a combination of the typical π-and T-type configurations, for constant current output applications. The input-output characteristics and efficiency characteristics are analyzed experimentally. The experimental results are compared to the recently evaluated simulation results of the proposed immittance converter. It is observed that the experimental results agree with those of the simulation ones, and confirm that the π-CLCL configuration is more efficient than the typical π-and T-type immittance converters while maintaining a nearly constant output current.

A method of analyzing the complex admittance of metal-insulator-semiconductor (MIS) structures has been developed with the aim to extract the density and capture cross section of interface traps from combined ac capacitance–voltage and conductance–voltage measurements at different frequencies. The procedure is applied to study dielectric stacks based on La2Hf2O7 high-κ dielectric, which could be considered as a SiO2 replacement for future transistors.

The problem of reconstruction of conductances in rectangular resistive grids from boundary measurements is studied. Several reconstruction algorithms based on optimization methods are compared in terms of numerical stability and accuracy of the results. Limitations of the algorithms are discussed and several improvements are proposed.

This paper examines a stability characteristic of gyrator type bilateral control in order to determine a definite feedback gain and scaling design. Stability is examined based on root locus. Maximum stable gain, transfer impedance and transfer admittance are observed in the examination. Moreover, it is observed that at certain transfer impedance and admittance, gyrator type bilateral control and transformer type bilateral control become equivalent to each other. Validity of the analysis and characteristics of several transfer impedance and transfer admittance design are examined based on experiments.

We present a technique, using the Imaginary Smith Chart, for determining the admittance of obstacles introduced into evanescent waveguide. The admittance of an inductive iris, capacitive iris, capacitive post, variable width strip and length of evanescent waveuide are investigated.

This paper is a tutorial introduction to the subject of conductance fluctuations observed in mesoscopic conductors at low temperatures, and the universal conductance fluctuation (UCF) theory proposed to explain them. The discovery of the fluctuations less than a decade ago has been followed by an intensive flurry of research activity, published almost entirely in the journals of solid-state physics. This paper surveys the subject from the viewpoint of a practising electron device engineer, with bias in favor of intuitive appeal rather than rigor, and should be helpful in understanding the primary literature on the subject. The nature of fluctuations and mesoscopic conduction are briefly introduced. Both theoretical and experimental results from the sizable literature on the subject are summarized here, emphasizing the characteristics of the fluctuations, the conditions under which they are observed, the mechanism of fluctuations, and the range of applicability of the UCF theory. >

Gas sensors have been fabricated using the single-crystalline SnO2 nanobelts. Electrical characterization showed that the contacts were ohmic and the nanobelts were sensitive to environmental polluting species like CO and NO2, as well as to ethanol for breath analyzers and food control applications. The sensor response, defined as the relative variation in conductance due to the introduction of the gas, is 4160% for 250 ppm of ethanol and −1550% for 0.5 ppm NO2 at 400 °C. The results demonstrate the potential of fabricating nanosized sensors using the integrity of a single nanobelt with a sensitivity at the level of a few ppb.

The piezoelectric transformer (PT) as a pressurized component used in fuse all-electronic safety and arming device improves its security and reliability. The manufacturing materials and geometric parameters error of PT results in the error of the equivalent circuit model parameters. In order to effectively obtain accurate equivalent model parameters, the admittance circle is used to measure equivalent circuit parameters of PT, to obtain its frequency characteristics, then to calculate the equivalent circuit model parameters. The measurement results provide a theoretical basis to the circuit design of the fuse all-electronic safety and arming device

The equal network is often used to analyze some questions in theory. For example, Two-terminal network can be equivalent to a voltage source. It is suitable for multiterminal network. A kind of system is established by using the equal network. The system is verified correctly by some examples. The establishment of equal network involves the branch's conductance and electromotive force (emf). The establishment of branch's conductance is certain, because the number of nodes is equal to the number of the ends. But the establishment of the emf is not certain. Finally, the optimization of the equal network is introduced. The aim of the optimization is to make its internal power loss less and make both structure and parameter economical and reasonable.

Based on the analysis of sealing-exhaust process for arc tube of ceramic metal halide lamp(CMH) and the calculation to a few key vacuum parameter, this report proposes a design plan of the sealing-exhaust equipment's vacuum system for arc tube of ceramic metal halide lamp, and finally tube of ceramic metal halide lamp, and finally verifies the conductance of vacuum system to reach the design desire.

Point/plane electrode configurations are studied here analytically and by a numerical finite element approach, with concordant results. In the formulas obtained for the admittance and impedance, one remarkable function appears, which is log(iω). Its representation in the complex graph is a horizontal line. The mechanism governing the impedance variation as a function of the frequency is fully described.

Analytical expressions for calculating the stationary yields of chemical products are derived in a general kinetic scheme for the multistep or sequential hopping rate processes. Established further is an exact mapping between the stationary chemical yields and the normalized electric direct currents.

Impedance and Admittance Control are two distinct implementations of the same control goal. It is well known that their stability and performance properties are complementary. In this paper, we present a hybrid system approach, which incorporates Impedance and Admittance Control as two extreme cases of one family of controllers. This approach allows to continuously switch and interpolate between Impedance and Admittance Control. We compare the basic stability and performance properties of the resulting controllers by means of an extensive case study of a one-dimensional system and present an experimental evaluation using the KUKA-DLR-lightweight arm.

The equivalent-admittance approach is used to simplify the matching of the symmetrical six-port waveguide junction. The equivalent-admittance data generated by the model show that inductive diaphragms are required. Tests on the resulting prototype have confirmed the measured VSWR to be less than 1.2 over the entire WR90 bandwidth.

An equivalent circuit has been developed for a four-port RF transformer by exploiting the symmetry of the device. The circuit consists of four driving-point admittance RLC networks mutually connected via a transforming circuitry, ensuring the symmetry. The measured 4-port frequency responses are converted to respective driving-point admittances, which are approximated by fitting the values of the lumped equivalent circuit 1-ports. Here, a commercial RF transformer has been modelled.

Starting with a circuit model form in − (g+jb)/Cω 0 = j 2/ω 0 [ω r (t) − Ω r + j(ω i (t) − Ω i ] is developed to describe the beam loaded admittance. In this equation, ω 0 = 1/√LC, the natural frequency of the unloaded oscillator. Ω r and Ω i are the real and imaginary parts of the cold tube complex frequency, Ω, while ω r and ω i are the real and imaginary portions of the hot tube complex frequency, ω. In this treatment, it is assumed that Ω = ω 0 to the lowest order. This result suggests that the instantaneous beam loaded admittance, g + jb, may be extracted from the output signal of the oscillator once the cold tube frequency and damping rates have been determined. This technique is used to analyze the behavior of a relativistic magnetron operating in the pi mode, simulated in MAGIC PIC. Application to experiments will be discussed.

We consider a particular class of molecular electronic devices (MEDs) built around the photoactive dithienylethene switch. Light of an appropriate frequency can convert the switch from a high to a low conductance form. Various derivatives of the dithienylethene that have recently been investigated experimentally are modeled. The transmission probabilities for the switches are analyzed and we provide an explanation for why certain switches, as a part of a MED, can only be converted from the closed to the open form, while for other switches, this process is reversible.

Measurements are made on N-silicon crystals grown by the floating zone (FZ) method and doped by diffusion with Pt. The parameters and distribution profiles of shallow and deep levels are minutely investigated by capacitance methods, namely by C–U characteristic, DLTS, and admittance spec-troscopy (AS). The levels at Ec −0.23 eV and Ev +0.33 eV are attributed to Pt, whereas those lying at Ec −0.32 eV and Ec −0.44 eV are probably not directly connected with Pt. Attention is devoted to the scattering of the measured values of parameters. Mit Platin dotierte N-leitende FZ-Si Kristalle werden mit kapazitiven Methoden eingehend untersucht. Die Parameter der Storstellen und der Konzentrationsprofile werden mittels C–U-Charakteristiken, DLTS-Messungen und Admittanz-Spektroskopie (AS) ermittelt. Niveaus bei Ec −0.23 eV und Ev +0,33 eV werden in Ubereinstimmungmit der Literaturmit Pt-Storstellen identifiziert, diejenigen bei Ec −0,32 eV und Ec −0,44 eV sind wahrscheinlich nicht mit Pt verbunden. Eine besondere Aufmerksamkeit wird der Streuung der ermitteiten Werte gewidmet.

Etude de l'interference quantique a travers ces structures, de la distribution hors equilibre des electrons de l'effet tunnel conduits par la tension de polarisation appliquee, et de l'effet des reservoirs (electrodes). Le comportement transitoire du courant d'effet tunnel est caracterise par le processus de construction des electrons de l'effet tunnel dans le puits quantique. La partie imaginaire de l'admittance est liee a la conductance par la relation de Kronig-Kramers

The evaluation of self and mutual admittances of CPW-fed slots on electrically thin dielectric substrates is addressed with reference to iterative array design procedures. A characterization of isolated slot self-properties indicated certain linear dependencies on slot dimensions, suggesting that less data may be required from computationally intensive a priori moment-method analyses of isolated slots. An approximate method for the fast, accurate calculation of mutual admittance between CPW-fed slots on electrically thin substrates is described. Its accuracy is shown to be comparable to moment-method-based calculations in IE3D. The method can be easily incorporated into iterative array design algorithms.

Noise effects in coupled interconnects, i.e. crosstalk induced glitch and crosstalk induced delay can significantly impact the performance of deep sub-micron (DSM) chips. Therefore, in this paper distributed RLGC transient model of coupled interconnects has been developed that will be useful for analyzing such crosstalk noise effects in DSM chips. The model accuracy is quite comparable to the PSPICE simulation results and yet the simulation speed is at least 11 times faster than the latter.

Hot-carrier degradation phenomena in n-channel MOSFETs (NMOSFETs) through the comparison between conventional and lightly doped drain (LDD) structure of 0.8-mum CMOS technology was described. This phenomenon was also observed in the conventional NMOSFETs. This is because of hot-electron trap in the gate accumulating carriers (holes) along the channel region near the drain. That is, these holes effectively increased the effective channel length. On the other hand, the lifetimes of conventional and LDD NMOSFETs defined as how long it takes the transconductance deviation to reach 10 %, which the LDD NMOSFETs are longer than conventional NMOSFETs under the same hot-carrier condition.

To carry out stability studies on more electric systems in which there is a preponderance of motor drive equipment, input admittance expressions are required for the individual pieces of equipment. In this paper the techniques of averaging and small-signal linearisation will be used to derive a simple input admittance model for a low voltage, trapezoidal back EMF, brushless, DC motor drive system.

The distributed capacitances between the strands of an inductive voltage divider degrade the voltage ratio. A calculation scheme to convert the distributed capacitances into equivalent concentrated capacitances at the taps is given. An optimized connection scheme for the strands is calculated to produce concentrated capacitances which are as equal and as small as possible. Capacitors are added at the taps for optimum equalization. The relative error of the output voltage for a 120-V:10-V divider has been reduced to less than 1*10/sup -7/ in phase and less than 1 mu rad in quadrature, at a frequency of 50 Hz. >

Summary form only given. This paper presents a Monte-Carlo model to explain the multipactor discharge and its high power absorption in a dielectric-loaded accelerating (DLA) structure reported recently. Kinematic calculation is performed to determine the susceptibility diagram, which is a useful tool in analyzing whether multipactor discharge will take place over a range of RF and DC electric fields for certain material. A resonant condition of a maximum growth region in susceptibility diagram has teen determined numerically and analytically. The constructed susceptibility diagram is compared with the simple dielectric case. Based on the constructed susceptibility diagrams, dynamic calculations for beam loading and its power absorption by the multipactor discharge are performed. It is found that the fraction of power absorbed by multipactor discharge at saturation is much larger than the case of a simple RF window, and it is sensitive to the incident power, which confirms the prior experimental results. This enhanced power absorption is due to the fact that the length of DLA structure is much larger than the radius of the structure. The difference between the resonant condition (due to phase focusing) and saturation (due to team loading) is clarified.

We report anomalous charging effect of single electrons (Coulomb diamonds) observed in carbon nanoscale peapod quantum dots that encapsulate a series of ${\mathrm{C}}_{60}$ molecules. We find that behaviors of diamonds are anomalously sensitive to back-gate voltages $({V}_{\mathrm{bg}})$, exhibiting two evidently different ${V}_{\mathrm{bg}}$ regions and a large polarity on ${V}_{\mathrm{bg}}$. In particular, we find only a sequence of one large diamond followed by three smaller ones existing around ground state. Magnetic-field dependence indicates the presence of shell filling by spin singlet to doubly degenerate electronic levels for these. The encapsulated-${\mathrm{C}}_{60}$ molecules indirectly affect this shell filling at low ${V}_{\mathrm{bg}}$ possibly via nearly free electrons. In contrast, they act as individual quantum dots coupled in series in high ${V}_{\mathrm{bg}}$ region. It directly contributes to highly overlapped very large diamonds. Moreover, we report power-law behaviors on conductance versus energy relationships observed in the same carbon nanoscale peapods. We find that the values of powers are also highly sensitive to applied ${V}_{\mathrm{bg}}$ with three different regions and anomalously high at high source-drain voltages. Because the power laws are found at voltages, which are the nearest outside of the above-mentioned fourfold Coulomb diamonds, correlation of the anomalous powers with orbital-related Tomonaga-Luttinger liquid is discussed.

An expression for the input admittance of a coaxially driven cylindrical cavity is presented. Two cases are presented: first, where the coaxial-line transition is located on one of the flat walls of an empty cavity, and secondly where there is a dielectric rod located coaxially between the two flat walls of the cavity. A comparison between the theory and measurements is presented which shows that the model is capable of yielding a high level of accuracy.

The parallel equivalent circuit for radio-frequency and microwave single-ended switched capacitor arrays (SSCAs) is investigated. In particular, the SSCA equivalent capacitance and resistance are highlighted and predicted by new closed-form mathematic expressions. The behavior of the SSCA with the control input and frequency is also analyzed in detail. The proposed model shows that the SSCA admittance depends on frequency, integration technology parameters, circuit size and control input. An ultra-wide-band SSCA, designed with standard 0.35 mum 2P4M mixed-signal CMOS technology, is also presented and used to assess the model accuracy. The model predictions match the computer simulations.