converting a transfer function to R L C network

[actra]

rlc transfer function

hello
is there any methods to convert a given transfer function to RLC network ?

 

[flatulent]

transfer function rlc

This is called network synthesis and goes back to 1930 or earlier. There are entire books and school courses on the subject.

Here are the steps that are used.

1. Specify the transfer function of a two port or the input impedance of a one port with a ratio of polynomials in the variable S.

2. Perform a test on the denominator polynomial to make sure the resulting network will have elements with positive values.

3. Do a partial fraction expansion or a continued fraction expansion on the function in 1 above. The partial will produce a set of RLC networks in series. The continued will produce a ladder network.

4. From the elements of the expansion in 3 above you can easily determine the value of the RLC values.

 

[Jack// ani]

rlc network

You should refer to F F Kuo's book Network Analysis & Synthesis

[note from flatulent: This 40 year old book is still the best one to learn from.]

 

[Jack// ani]

rlc network synthesis

Hi flatulent,

Thanks for your comment. And if I'm not wrong Kuo also contributed a lot in development to theory behind circuit synthesis. Thats why is book is considered as a classic. Another old classic is M E Valkenburg book.

Reg

 

[flatulent]

rlc function transfer

Here is a bit of history. The early work in this area was done by industrial laboratories, mostly telephone ones. The work was published in the internal journal. BSTJ is one example. Then there was a lull between 1930-1940 and then the war efforts caused more development. There were some textbooks published 1945-1962 but there were not that many students. Then the large group of students born after 1945 came along and they were the ones that learned from the two authors named in the previous post. This made the two authors well known.

The first rigorous filter work was done by Campbell of the Bell Labs prior to about 1920. He invented the image parameter filters. He also invented the Smith Chart around this time. This chart was reinvented in Japan in 1937 and again in the US in 1938. It was only the microwave and UHF work in the war that made the chart widely used. Since so many people entered engineering after 1938 Smith got the credit.

This is sort of like the so called Gilbert Mixer. This dates back to the days of valves/tubes and had been published in company advertising journals in Europe and patented in the US years before Gilbert did the very clever invention of putting a predistorter on the input to make it a linear four quadrant multiplier. The predistorter is very much like a floating current mirror.