Coupling in an array of three coils as function of pitch

Coupling in an array of three coils as function of pitch

This script enables to compute coupling in coil array. The considered array is composed of three air-core, circular coils, with their centers set at edges of a triangle. The coupling is computed as function of axis pitch between the coils. At pitch values smaller than the diameter of the coil, there is a partial overlap between them. For such situation, vertical separation is set as one of the input parameters. The coil 1 is assumed to be on the top of the stack, coil 2, in the middle, and coil 3 at the bottom. The vertical separation between the coil 1 and 2 is identical to the vertical separation of coil 2 and 3.
The script is based on the paper:
N. Tal, Y. Morag, and Y. Levron, “Magnetic Induction Antenna Arrays for MIMO and Multiple-Frequency Communication Systems,” Progress In Electromagnetics Research C, vol. 75, pp. 155–167, 2017.
Available online at: http://www.jpier.org/PIERC/pierc75/16.17030703.pdf

The input parameters are given along with units:
h_s: vertical spacing between coils - the distance between the bottom conductor of the top coil to the top conductor of the bottom coil [m]
R_inner: inner radius of the coil [m]
n_x: number of layers
n_y: %number of turns in each layer
b: wire radius [m]
Kw: coil filling factor - turn-to-turn pitch divided by wire diameter (Kw>1)
d_ab1: coil 1 - coil 2 axes pitch distance vector
d_ab2: coil 1 - coil 3 axes pitch distance vector

The main function name is: coupled_array_of_three_main_func.m