Analysis of a Substrate Integrated Waveguide Hybrid Ring (Rat-Race) Coupler

Table 1

IWO parameters values for Figure 1(a).

Symbol	Quantity	Value
No	Number of initial population	5
itmax	Maximum number of iterations	1000
dim	Problem dimension	3
𝑃max	Maximum number of plant population	5
𝑆max	Maximum number of seeds	25
𝑆min	Minimum number of seeds	0
𝑛	Nonlinear modulation index	3
𝜎initial	Initial value of standard deviation	2
𝜎final	Final value of standard deviation	0.01
𝑅1ini	Initial search area	2 mm to 20 mm
𝑅2ini		4 mm to 30 mm
𝑅3ini		10 mm to 45 mm