# Large Finite Array Solver

Large Finite Array Solver
 Circular array of pyramidal horns

The large finite array solver presents a very efficient solution for the design of large, finite sized arrays of metallic elements and caters for regular or irregularly spaced array elements.  Each individual element may be fed with appropriate magnitude and phase of excitation that does not have to follow any pattern.  Self-coupling and mutual-coupling are taken into account and the edge effects of the finite array are accurately modeled.

The solver method is based on the Domain Green's Function Method (DGFM) and is a valuable design tool for array designers because it solves the MoM problem for a single element of the array and then appropriately couples this solution to all elements of the array, while feeding them individually.  This method requires computational resources in the order of the solution of a single array element which represents a large saving over other solution options for large, but finite, arrays.

CADFEKO supports this solution method with intuitive methods for specifying arrays in the format of:

• Linear or planar arrays
• Circular or cylindrical arrays
• Custom positioned element arrays

Array configurations that were designed with Antenna Magus may be exported from Antenna Magus in an XML format, which can be directly imported in FEKO.

### Examples

The DGFM computes coupling information for each element in the array in an optimal manner.  Memory saving is immediately apparent, but solution time savings will only present large savings for larger models.  The followings examples demonstrate these savings.

Linear 12x1 microstrip array with squint main-lobbe Planar 12x12 microstrip array

• 12x1 microstrip elements modeled with planar Green's Function
• Finite arrays (DGFM) / Normal MoM solution:
• 11 % memory
• 103 % runtime
• 12x12 microstrip elements modeled with planar Green's Function
• Finite arrays (DGFM) / Normal MoM solution:
• 1.0 % memory
• Could not run normal solution (too large)

3D gain pattern of 12x12 microstrip array