gammain

Input reflection coefficient of 2-port network

Syntax

coefficient = gammain(s_params,z0,zl)
coefficient = gammain(hs,zl)

Description

coefficient = gammain(s_params,z0,zl) calculates the input reflection coefficient of a 2-port network. s_params is a complex 2-by-2-by-M array, representing M 2-port S-parameters. z0 is the reference impedance Z0; its default value is 50 ohms. zl is the load impedance Zl; its default value is also 50 ohms. coefficient is an M-element complex vector.

coefficient = gammain(hs,zl) calculates the input reflection coefficient of the 2-port network represented by the S-parameter object hs.

Examples

collapse all

Calculate the input reflection coefficients at each index of an S-parameter array.

  ckt = read(rfckt.amplifier,'default.s2p');
  s_params = ckt.NetworkData.Data;
  z0 = ckt.NetworkData.Z0;
  zl = 100;
  coefficient = gammain(s_params,z0,zl)
coefficient = 191×1 complex

  -0.7247 - 0.4813i
  -0.7323 - 0.4707i
  -0.7397 - 0.4601i
  -0.7470 - 0.4495i
  -0.7542 - 0.4389i
  -0.7612 - 0.4284i
  -0.7682 - 0.4179i
  -0.7750 - 0.4075i
  -0.7817 - 0.3972i
  -0.7883 - 0.3870i
      ⋮

Algorithms

gammain uses the formula

Γin=S11+(S12S21)ΓL1S22ΓL

where

ΓL=ZlZ0Zl+Z0

Introduced before R2006a