Squid

Squid (Stable quasiconvex identification) is a open-source matlab tool for the generation of reduced order linear system models from available transfer function data points. The tool is based on a quasi-convex relaxation of a system identification problem subject to stability and passivity constraints.

Download Quid (readme files, examples and demos are included in the distribution):

• Download SquidBasicv1.0.zip: the basic version of the algorithm without passivity constraints.
• Download SquidPRv1.0.zip: guarantees positive real passivity of the generated reduced models (for transfer function data points that represent impedance or admittance).
• Download SquidBRv1.0.zip: guarantees bounded real passivity of the generated reduced models (for transfer function data points that represent scattering parameters).

Relevant Publications:

1. K. C. Sou, A. Megretski, L. Daniel, "A Quasi-Convex Optimization Approach to Parameterized Model Order Reduction", IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems, Vol 27, No 3, March 2008.
2. Kin Cheong Sou, “Convex Optimization Methods for Model Order Reduction”, PhD Thesis, Massachusetts Institute of Technology, September 2008.

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Back to:

• Computational Prototyping Group page at M.I.T.

Last Updated 9 October, 2009.

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