Phaseless Spherical Near-Field to Far-Field Transformation Algorithm via Sparsity of Spherical Mode Coefficients

<div>The reconstructed <svg height="11.927pt" id="M146" style="vertical-align:-3.291101pt" version="1.1" viewbox="-0.0498162 -8.6359 13.1924 11.927" width="13.1924pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M593 650H142L136 622C219 616 224 611 209 531L130 120C114 39 108 34 23 28L17 0H501C518 32 557 130 568 158L540 169C519 132 495 93 469 70C439 43 409 35 332 35C272 35 241 37 225 50C211 61 211 89 222 149L253 320H350C441 320 443 312 441 239H471L510 434H481C455 366 448 358 360 358H260L303 572C311 613 312 615 348 615H431C509 615 522 603 532 581C544 555 546 531 545 491L574 493C583 555 592 631 593 650Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,7.943,3.132)"><path d="M482 498C482 606 448 710 328 710C138 710 24 416 24 218C24 99 58 -12 184 -12C373 -12 482 294 482 498ZM395 521C395 483 391 449 383 395H128C158 537 226 671 312 671C388 671 395 566 395 521ZM375 342C348 190 284 25 192 25C128 25 109 116 109 199C109 243 112 292 121 342H375Z"></path></g></svg> and <svg height="14.1649pt" id="M147" style="vertical-align:-5.529pt" version="1.1" viewbox="-0.0498162 -8.6359 13.9871 14.1649" width="13.9871pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M593 650H142L136 622C219 616 224 611 209 531L130 120C114 39 108 34 23 28L17 0H501C518 32 557 130 568 158L540 169C519 132 495 93 469 70C439 43 409 35 332 35C272 35 241 37 225 50C211 61 211 89 222 149L253 320H350C441 320 443 312 441 239H471L510 434H481C455 366 448 358 360 358H260L303 572C311 613 312 615 348 615H431C509 615 522 603 532 581C544 555 546 531 545 491L574 493C583 555 592 631 593 650Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,7.943,3.132)"><path d="M569 272C569 396 502 451 440 451C377 451 308 398 280 296C262 229 239 121 223 41C163 58 116 110 116 203C116 313 187 386 283 428L269 460C133 413 24 332 24 189C24 85 87 3 215 -10C187 -153 174 -212 164 -249L173 -257C208 -253 245 -243 260 -214L295 -5C427 6 569 118 569 272ZM493 270C493 139 401 42 302 37L357 327C369 388 390 405 412 405C438 405 493 369 493 270Z"></path></g></svg> of horn antenna by adopting the proposed algorithm. (a) <span class="nowrap"><svg height="11.927pt" id="M148" style="vertical-align:-3.291101pt" version="1.1" viewbox="-0.0498162 -8.6359 13.1924 11.927" width="13.1924pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M593 650H142L136 622C219 616 224 611 209 531L130 120C114 39 108 34 23 28L17 0H501C518 32 557 130 568 158L540 169C519 132 495 93 469 70C439 43 409 35 332 35C272 35 241 37 225 50C211 61 211 89 222 149L253 320H350C441 320 443 312 441 239H471L510 434H481C455 366 448 358 360 358H260L303 572C311 613 312 615 348 615H431C509 615 522 603 532 581C544 555 546 531 545 491L574 493C583 555 592 631 593 650Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,7.943,3.132)"><path d="M482 498C482 606 448 710 328 710C138 710 24 416 24 218C24 99 58 -12 184 -12C373 -12 482 294 482 498ZM395 521C395 483 391 449 383 395H128C158 537 226 671 312 671C388 671 395 566 395 521ZM375 342C348 190 284 25 192 25C128 25 109 116 109 199C109 243 112 292 121 342H375Z"></path></g></svg>.</span> (b) <span class="nowrap"><svg height="14.1649pt" id="M149" style="vertical-align:-5.529pt" version="1.1" viewbox="-0.0498162 -8.6359 13.9871 14.1649" width="13.9871pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M593 650H142L136 622C219 616 224 611 209 531L130 120C114 39 108 34 23 28L17 0H501C518 32 557 130 568 158L540 169C519 132 495 93 469 70C439 43 409 35 332 35C272 35 241 37 225 50C211 61 211 89 222 149L253 320H350C441 320 443 312 441 239H471L510 434H481C455 366 448 358 360 358H260L303 572C311 613 312 615 348 615H431C509 615 522 603 532 581C544 555 546 531 545 491L574 493C583 555 592 631 593 650Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,7.943,3.132)"><path d="M569 272C569 396 502 451 440 451C377 451 308 398 280 296C262 229 239 121 223 41C163 58 116 110 116 203C116 313 187 386 283 428L269 460C133 413 24 332 24 189C24 85 87 3 215 -10C187 -153 174 -212 164 -249L173 -257C208 -253 245 -243 260 -214L295 -5C427 6 569 118 569 272ZM493 270C493 139 401 42 302 37L357 327C369 388 390 405 412 405C438 405 493 369 493 270Z"></path></g></svg>.</span></div>

International Journal of Antennas and Propagation

fig21

Figure 21

Figure 21: Phaseless Spherical Near-Field to Far-Field Transformation Algorithm via Sparsity of Spherical Mode Coefficients 