Three-Mode Vortex Wave Generator with Double-Layer Patch Antennas

<p>Return loss and inserting loss for the OAM generator (a=18.3mm, 0.46<span class="nowrap"><svg height="12.5794pt" id="M26" style="vertical-align:-3.29107pt" version="1.1" viewbox="-0.0498162 -9.28833 12.8362 12.5794" width="12.8362pt" xmlns="http://www.w3.org/2000/svg"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M529 97L508 118C475 75 449 58 438 58C428 58 421 66 415 104C393 234 374 403 364 496C345 670 307 712 254 712C220 712 174 691 153 669L161 645C176 653 194 658 206 658C237 658 261 640 278 562C287 522 290 483 293 434C223 269 110 105 23 9L32 -12C59 -6 85 0 108 7C152 64 251 252 300 366C307 297 315 221 337 82C346 24 363 -12 393 -12C425 -12 475 13 529 97Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,7.761,3.132)"><path d="M245 635C92 635 37 457 37 312C37 149 91 -12 244 -12C395 -12 449 166 449 312C449 469 395 635 245 635ZM243 598C332 598 358 454 358 312C358 173 334 26 245 26C158 26 128 174 128 313S152 598 243 598Z"></path></g></svg>).</span></p>

International Journal of Antennas and Propagation

Three-Mode Vortex Wave Generator with Double-Layer Patch Antennas

Figure 5