Version 4g, August 2006 Two methodologies are presented for predicting the phase noise and jitter of a PLLbased frequency synthesizer using simulation that are both accurate and efficient. The methodologies begin by characterizing the noise behavior of the blocks that make up the PLL using transistor-level RF simulation. For each block, the phase noise or jitter is extracted and applied to a model for the entire PLL.

The origins and characteristics of cyclostationary noise are described in a way that allows designers to understand the impact of cyclostationarity on their circuits. In particular, cyclostationary noise in time-varying systems (mixers), sampling systems (switched filters and sample/holds), thresholding systems (logic circuitry), and autonomous systems (oscillators) is discussed.

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Most RF circuit analysis tools use either shooting-Newton or harmonic balance methods. Neither can efficiently achieve high accuracy on strongly nonlinear circuits possessing waveforms with rapid transitions. We present a multi-interval-Chebyshev (MIC) method that discretizes the circuit equations by dividing the simulation domain into a set of intervals whose size is adaptively chosen and using Chebyshev polynomials to represent the solution in each interval. The MIC method has excellent stability properties, is as effective at solving nonlinear problems as shooting techniques, can achieve high resolution on a wide variety of circuits, and in conjunction with an appropriate preconditioner can be combined with matrix-implicit Krylov-subspace solvers to analyze large circuits with moderate computational cost.

The history of RF and microwave computer-aided engineering is documented in the annals of the IEEE Microwave Theory and Techniques Society. The era began with elaborate analytically based models of microwave components and simple computer-aided techniques to cascade, cascode, and otherwise connect linear component models to obtain the responses of linear microwave circuits. Development has become rapid with today’s computer-oriented microwave practices addressing complex geometries and with the ability to globally model and optimize large circuits. The pursuit of accurate models of active devices and of passive components continues to be a key activity.

Abstract. Sensornets have been proposed consisting of thousands or tens of thousands of nodes. Economic and logistical considerations imply predeployment evaluation must take place through simulation rather than field trials. However, most current simulators are inadequate for networks with more than a few hundred nodes. In this paper we demonstrate some properties of sensornet application and protocols that only emerge when considered at scale, and cannot be effectively addressed by representative small-scale simulation. We propose a novel multi-phase approach to radio propagation modelling which substantially reduces computational overhead without significant loss in accuracy.

In this paper, we describe a new circuit simulator named HomSSPICE that incorporates homotopy algorithms for steady-state simulations of oscillators. The new simulator is based on SSPICE and HOMPACK. It employs a homotopy-based algorithm that is suitable for the periodic steady-state simulations of autonomous circuits, such as sinusoidal oscillators.

Simulation of RF circuits often demands analysis of distributed component models that are described via frequency-dependent multiport Y , Z,orS parameters. Frequency-domain methods such as harmonic balance are able to handle these components without difficulty, while they are more difficult for time-domain simulation methods to treat. In this paper, we propose a hybrid frequency-time approach to treat these components in steady-state time-domain simulations. Efficiency is achieved through the use of the multiinterval Chebyshev (MIC) simulation method and a low-order rationalfitting model for preconditioning matrix-implicit Krylov-subspace solvers.

WITCHED capacitor circuits have become increasingly popular in recent years. This is due in large part to the availability of the high quality switches provided by CMOS technology. Further, switched capacitor designs have greatly benefited from the substantial developments in the field of digital signal processing. The dependence of filter coefficients on capacitance ratios allows precision on the order of 0.1 % in switched capacitor filter implementations. Switched capacitor circuits can also be used

The expansion of the market for portable wireless communication devices has given a tremendous push to the development of a new generation of low-power radio frequency integrated circuit (RFIC) products. In this fast-growing environment where time-to-market constraints force tight schedules, having a good design methodology, innovative computer-aided design (CAD) tools, and a well-integrated design system are key factors to success. In this paper, we describe a design system developed to provide the designer with everything necessary to accurately predict the behavior of RFIC devices, including layout and package parasitic effects. We show how important a well-defined and integrated system is to manufacturing a design that meets specifications at the minimum cost, in the minimum time. A close link between schematic, models, and layout is of paramount importance to ensure the accuracy needed for low-power RF design. We give an overview of the advanced methods and tools currently available for simulation and noise analysis of RF devices. Finally, we show a design example that obtained first-silicon success. Keywords—Design automation, design methodology, design system, device modeling, layout design, layout parasitics, low power, power amplifier, RF integrated circuit design, RF integrated circuit simulation, substrate coupling, substrate noise. I.