broadband impedance matching using negative-image modeling

pragash

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I want to do broadband impedance matching using the negative-image modeling method. I have given all the steps of the negative-image modeling method. my question is on step one as of now but I have given all the steps needed to do broadband impedance matching for an LNA.

The steps to do broadband matching using the negative-image modeling method are:

  1. Create an equivalent component model for transistor input impedances and output impedance across the frequency. Assume Figure 1 is an equivalent component model for transistors, either input impedance or output impedance. How can I create an equivalent component model for transistor input and output impedances?

Figure 1: Equivalent component model for transistor input impedances or output impedance across the frequency

  1. Negative-image modeling begins in Figure 2 by introducing negative elements -L, -C, and -C’ to cancel the corresponding positive parasitic elements L, C, and C_ of the transistor model.

Figure 2: Equivalent component model for transistor input impedances and output impedance across the frequency

  1. Finally, an inductive-T dualizer completes the non-Foster match in Figure 3.

Figure 3: added inductive-T dualizer completes the match to 50;

  1. The matching circuit can also be simplified, as shown below;

Figure 4: simpler matching structure is shown to work as well as that of Figure 3, where L1 is positive and L2, L3, and C4 are negative;

  1. In Figures 1 - 4, the assumption is that individual negative elements are realized by terminating a Negative Impedance Converter (NIC) in the corresponding positive element, as shown in Figure 5.

Figure 5: realizing a negative element with a NIC, where k is positive

  1. One may alternatively bracket an interconnection of positive elements with NICs to effectively negate that portion of the circuit, as shown in Figure 6.

Figure 6: structure equivalent to Figure 4, where all elements are positive.
 

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