Direction Finding Using Multiple Sum and Difference Patterns in 4D Antenna Arrays

<table>Calibrated difference-sum ratio <svg height="16.275" id="M117" style="vertical-align:-3.13504pt" version="1.1" viewbox="0 0 53.575001 16.275" width="53.575001" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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q12 68 2 83t-72 22l6 28h257l-7 -28q-62 -7 -76 -21.5t-27 -83.5l-32 -172q29 11 78 46q112 84 217 179q18 16 23.5 25.5t-1 14.5t-26.5 8l-30 4l5 28h249z" id="x1D43E"></path></g>
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</svg> based on measured active element patterns.</table>

International Journal of Antennas and Propagation

fig12

Figure 12

Figure 12: Direction Finding Using Multiple Sum and Difference Patterns in 4D Antenna Arrays 