Multi-slice behavioral model of RF systems and devices (original) (raw)

Circuit-Level Nonlinear Simulation of RF/Microwave Systems

2008

The circuit-level simulation of nonlinear microwave systems of complex topology is a challenging problem whose solution is being pursued by several research teams. The paper discusses a self-consistent set of modern computational concepts providing an effective approach to this task. The reference CAD environment is given by harmonic-balance techniques based on Krylov-subspace model-order reduction. The system is described as a whole at the data entry level, but is automatically split into the interconnection of a near-optimal number of nonlinear blocks at run time. The resulting multiple-block structure is then exploited by the domain-partitioning concept. Voltages at the connection ports are treated as auxiliary unknowns to be determined simultaneously with the block state variables, which results in a sparse Jacobian matrix with a well-defined sparsity pattern. A block-wise constant spectrum is used rather than a common spectrum by considering for each block only the set of lines that are relevant to the block electrical function, which leads to a very significant reduction in the number of problem unknowns. System simulation under digitally modulated RF drive is reduced to a sequence of modified multitone harmonic-balance analyses that are backwards coupled through the envelope dynamics. Besides providing high numerical efficiency, this set of techniques opens the way to an effective co-simulation of RF and baseband transceiver sections.

Capturing asymmetry in distortion of an RF system using a multislice behavioral model

IEEE Microwave and Wireless Components Letters, 2006

Baseband effects result in asymmetrical distortion of RF communication signals through the interaction of basebandrelated distortion with in-channel distortion. Here, a behavioral model architecture that captures these asymmetries and can be implemented in a variety of circuit and system simulators is presented. The architecture has two or more slices with each slice corresponding to different frequency bands or multiple parallel nonlinear processes. Each slice could comprise any conventional narrow-band functional model. Here, the behavioral model is extracted using AM-AM and AM-PM measurements for the first slice and phase and amplitude measurement of intermodulation components for the second slice.

Deterministic and Stochastic Behavioral Modeling of RF Front Ends

… and Millimeter-Wave …, 2006

Behavioral models developed using discrete-tone characterization can be used to capture the response of an RF front end to stochastic signals. It is important that the model architecture capture all nonlinear effects and that the proper translation of the derived envelope model be transformed into an instantaneous model. Here the requirements for the transformation are presented, a multi-slice model architecture that can capture complex behavior from narrow-band measurements is presented together with an extraction ...

GLOBAL MODELING OF RF AND MICROWAVE CIRCUITS

2002

Advances in computer hardware and algorithmic technology have brought us to the brink of being able to model large mixed-signal circuits incorporating comprehensive modeling of the full physics of devices in a circuit model. In this paper we describe an approach to delivering a revolutionary modeling tool that implements new modeling and simulation abstractions, fast linear and nonlinear solvers, full-wave EM modeling for on-chip parasitics and integrated RF/microwave circuit design modeling, digital and analogue behavioral modeling, and advanced electrothermal modeling.

Simulation and Automated Modeling of Microwave Circuits: State-of-the-Art and Emerging Trends

IEEE Journal of Microwaves

Microwave modeling and simulation are essential to designing microwave circuits and systems. Although fundamental concepts and approaches for modeling and simulation are mature, the drive to higher frequencies, tighter design margins, and more functionality/complexity of circuits continue to defy the capabilities of existing modeling and simulation methods. Newer algorithms are being developed to address the speed, accuracy and robustness of design algorithms. Coupled with the advent of more powerful computers and algorithms, microwave design automations are solving much more complex problems in much shorter time than previously imaginable. This paper describes the advances and state-of-the-art in automated modeling and simulation. Automated data-driven modeling approaches covering data sampling/generation, model structure adaptation, and model training/validation are described. Simulation of nonlinear microwave circuits is described covering formulations of simulation equations and advanced solution algorithms addressing problem size, convergence speed and solution accuracy. The descriptions highlight fundamental concepts, advanced methodologies, and future trends of development.

A behavioral model development methodology for microwave components and integration in VHDL-AMS

Microelectronics Journal, 2007

The new generation of system-on-chip (SoC) incorporates digital, analogue, radiofrequency (RF)/microwave and mixed-signal components. Therefore, novel design methodologies must be developed to direct the design of these mixed-technology systems, which will have to include accurate behavioral libraries of devices and processes. Thus, this paper describes a behavioral modeling approach which generates accurate empirical models for RF/microwave devices and that can be easily integrated into a VHDL-AMS simulator. This approach is applied to a microwave tunable phase shifter and it is illustrated by the development of a VHDL-AMS model library for RF/microwave applications. r

Capturing asymmetrical spectral regrowth in RF systems using a multislice behavioral model and enhanced envelop transient analysis

International Journal of RF and Microwave Computer-Aided Engineering, 2006

Nonlinear distortion in RF and microwave systems results in spectral regrowth of digitally-modulated signals. The distortion above and below the main channel can be at different levels and this is attributed to baseband effects. This paper presents a new multi-slice behavioral model architecture that captures this asymmetry and can be implemented in a variety of circuit simulators including Spice, Harmonic Balance, Envelope Transient and System Simulators. The work is experimentally validated using a HBT power amplifier at 2.5 GHz driven by a WCDMA signal. The model is used with envelope transient circuit simulation which is enhanced to accommodate an arbitrary baseband transfer function.

Automatic generation of RF compact models from device simulation

2002

We review a recently proposed methodology for automatic generation of equivalent circuits from physical device simulation. The method is based on the calibration on a simplified equivalent-circuit model on simulation results, and can achieve an optimum balance of model complexity, accuracy, and generality. We discuss some of the possible applications of the technique to the modeling of active devices, parasitic elements, and complex physical effects such as selfheating and hot-carrier transport.

Modeling of integrated RF passive devices

IEEE Custom Integrated Circuits Conference 2010, 2010

We describe the use of an electromagnetic (EM) simulator for modeling integrated RF components and circuits. Modern EM simulators are fast and accurate enough to provide good models of such components. An important aspect of advanced IC processes is that the physical properties of wires (width, thickness, and resistance) vary depending on the surrounding wiring. We discuss how the EMX simulator [1] handles widthand spacing-dependent properties in the process description. Because the simulator handles mask-ready layout without the need for manual simplification, it is feasible to simulate thousands of possible designs and build scalable component models. Such scalable models allow fast choices of optimal components that meet user-supplied specifications.