| Popis: |
This chapter describes the circuit synthesis approach, based on the [ABCD] transfer matrix, or the “chain” matrix, as it is sometimes known. The network synthesis procedure is demonstrated by first building the A(s), B(s), C(s), and D(s) polynomials, corresponding to a third‐degree lowpass prototype ladder network with the elements C 1 ,1 1 , and C 2 . Such prototype networks require the hypothetical frequency‐invariant reactance elements (FIR). Another element that is required in the synthesis of filters at microwave frequencies is the frequency‐invariant impedance or admittance inverter, commonly referred to as the immittance inverter. The chapter describes the evaluation of the overall [ABCD] and the equivalent admittance [y] matrix from the characteristic polynomials of the desired filter function. From this matrix, it synthesizes the network given its topology. The chapter concentrates on the synthesis of parallel‐connected components in an open‐wire transmission environment, because many waveguide and coaxial elements are modeled directly as shunt‐connected elements. |
