# Improved Feedback Theory

@article{Pellegrini2009ImprovedFT, title={Improved Feedback Theory}, author={B. Pellegrini}, journal={IEEE Transactions on Circuits and Systems I: Regular Papers}, year={2009}, volume={56}, pages={1949-1959} }

A previous cut-insertion theorem for linear circuits and its application to a generalization of the elementary feedback theory are further extended. The new theorem is based on the splitting of an arbitrary node into two nodes and on the insertion between them and another arbitrary ldquoreferencerdquo node, of a three-terminal circuit which keeps the network currents and voltages unchanged. The system analysis is in turn performed on the equivalent cut network by means of the techniques for two… Expand

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#### 18 Citations

Feedback network analysis: an eclectic approach

- Computer Science
- Int. J. Circuit Theory Appl.
- 2015

A novel approach to feedback in linear electrical networks is proposed that generalizes the elementary one and circumvents some drawbacks and limitations that may be encountered with other general methods. Expand

Calculation of closing impedance in feedback systems based on cut-insertion theorem

- Mathematics, Computer Science
- 2014 IEEE 57th International Midwest Symposium on Circuits and Systems (MWSCAS)
- 2014

The paper shows how to circumvent this difficulty: using the cut-inserted two-port which includes an independent current (voltage) source on one side of the cut and an independent voltage source on the other side one obtains the signal graph of the feedback system of order two. Expand

Critical analysis of cut-insertion theorem

- Mathematics, Computer Science
- 2012 IEEE 55th International Midwest Symposium on Circuits and Systems (MWSCAS)
- 2012

It is shown that all cut-insertion equivalent networks can be obtained using a simple extension of the substitution theorem using two voltage sources connected in parallel between a chosen and reference node. Expand

Gain at an Arbitrary Cut in a Linear Bilateral Network, and Its Relation to Loop Gain in Feedback Amplifiers

- Mathematics, Computer Science
- IEEE Transactions on Circuits and Systems I: Regular Papers
- 2015

Neither the gain at a cut nor return ratio meets a usual expectation for loop gain in a feedback amplifier. Expand

On loop gain in linear networks

- Mathematics, Computer Science
- 2013 IEEE International Symposium on Circuits and Systems (ISCAS2013)
- 2013

The paper clarifies the difficulties occurring in definition of loop gain in linear networks. The cut-insertion theorem allows one to obtain the parameters of the feedback system resulting from… Expand

Novel Feedback Theory of Electric Circuits—Part I: Cut-Based Decomposition

- Mathematics, Computer Science
- IEEE Transactions on Circuits and Systems I: Regular Papers
- 2012

A novel cut- based decomposition for transfer functions of linear time-invariant circuits is introduced and an invariance property, with respect to the cut, is proven for the set of quantities introduced by this cut-based decomposition. Expand

Novel Feedback Theory of Electric Circuits—Part II: Loop Invariants

- Mathematics, Computer Science
- IEEE Transactions on Circuits and Systems I: Regular Papers
- 2012

A novel cut- based decomposition for transfer functions of linear time-invariant circuits is introduced and an invariance property, with respect to the cut, is proven for the set of quantities introduced by this cut-based decomposition. Expand

On feedback systems built around cut-inserted ideal transformer

- Mathematics, Computer Science
- 2014 IEEE International Symposium on Circuits and Systems (ISCAS)
- 2014

It is shown that introducing the second additional transformer in cascade connection with the first one and doing the cut in the wire between the transformers one may reduce this method to the previously known Cut-Insertion Theorem (CIT) method. Expand

Synthesis-oriented double-loop feedback model

- Computer Science, Engineering
- Int. J. Circuit Theory Appl.
- 2017

A single-loop synthesis-oriented feedback model is developed that enables the full synthesis of feedback amplifiers in a hierarchical and systematic way, and this model is subsequently extended to a double- loop synthesis model, so that also feedback amplifier with a characteristic input or output impedance—employing two feedback loops—can be synthesized through the same systematic approach. Expand

A Novel General-Purpose Theorem for the Analysis of Linear Circuits

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- 2021

A novel general-purpose theorem for the analysis of linear circuits is stated and proven, and two equivalent parameters have to be found to determine the variable of interest, thus resulting in a more straightforward analysis technique. Expand

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