M.M. Zharov

Bio: M.M. Zharov is an academic researcher from Russian Academy of Sciences. The author has contributed to research in topics: Harmonic balance & Phase noise. The author has an hindex of 7, co-authored 40 publications receiving 127 citations.

Iterative solution of linear systems in harmonic balance analysis

Abstract: Harmonic balance (HB) is a steady-state simulation technique of primary interest for RF and microwave circuits. Krylov subspace methods promise efficient solution of the large linear systems that arise in HB simulators. This paper deals with an experimental investigation of GMRES and QMR, two leading Krylov subspace methods as applied to the HB problem. The problem of coordinating the linear solver's accuracy with the error at the nonlinear level is also discussed.

Method and apparatus for distortion analysis in nonlinear circuits

Abstract: A circuit on an integrated circuit is made from a design that is verified using a design tool. The design tool takes a model of the circuit and generates equations with respect to nodes on the circuit. The time consuming task of completely determining the voltage at each node is performed for a predetermined input. To determine the node voltages for other signals, the first order transfer function of the equations is taken and then calculated for the predetermined input. A first order estimate of the node voltages is achieved using this first order transfer function and the node voltages determined from the predetermined input. A second order estimate is achieved using the first order transfer function and the first order estimate. A third order estimate is achieved using the first order transfer function and the second order estimate. The circuit design is verified for manufacturabiltity then manufactured.

Injection locking conditions under small periodic excitations

Abstract: Injection locking of oscillators subject to small periodic excitations is derived from existence conditions of the solution of the small signal harmonic balance degenerate system. The resulting expression for the locking range can be applied to any oscillator circuit with arbitrary periodic injection waveform, and can be easily implemented into a circuit simulator. The application of the general expression to some special cases is considered, and comparison with known results is given. Theoretical results are confirmed by SPICE simulations.

Analysis of oscillator injection locking by harmonic balance method

Abstract: A new approach to analyze injection locking mode of oscillators under small external excitation is proposed. The proposed approach exploits existence conditions of the solution of HB linear system with degenerate matrix. The method allows one to obtain the locking range for an arbitrary oscillator circuit with an arbitrary periodic injection waveform. The approach can be easily implemented into a circuit simulator. Examples are given to confirm the correctness of the new approach.

Smoothed form of nonlinear phase macromodel for oscillators

Abstract: This paper proposes an improvement to the well-known oscillator nonlinear phase macromodel based on Floquet theory. A smoothed form of the nonlinear phase macromodel is derived by eliminating highly oscillatory terms in the macromodel, resulting in a significant speed-up in transient simulation. For an LC oscillator under sinusoidal excitation the new macromodel is equivalent to the Adler model. Numerical experiments confirm a considerable decrease of computational efforts. It is further shown that the new macromodel allows one to perform phase noise analysis of locked oscillators under arbitrary periodic injection.

A Linear-Centric Modeling Approach to Harmonic Balance Analysis

Abstract: In this paper, we propose a new harmonic balance simulation methodology based on a linear-centric modeling approach. A linear circuit representation of the nonlinear devices and associated parasitics is used along with corresponding time and frequency domain inputs to solve for the nonlinear steady-state response via successive chord (SC) iterations. For our circuit examples, this approach is shown to be up to 60/spl times/ more run-time efficient than traditional Newton-Raphson (N-R) based iterative methods, while providing the same level of accuracy. This SC-based approach converges as reliably as the N-R approaches, including for circuit problems which cause alternative relaxation-based harmonic balance approaches to fail. The efficacy of this linear-centric methodology further improves with increasing model complexity, the inclusion of interconnect parasitics and other analyses that are otherwise difficult with traditional nonlinear models.