Characteristic Mode-Based Neutralization Line Design for MIMO Antenna

<div>Simulated normalized radiation patterns of antenna #2 with and without NL. <object data="https://static.hindawi.com/articles/ijap/volume-2022/9669114/figures/9669114.tab-inline.001.svgz" name="9669114.tab-inline.001" type="image/svg+xml"></object><svg height="11.927pt" id="M17" style="vertical-align:-3.291101pt" version="1.1" viewbox="-0.0498162 -8.6359 14.0797 11.927" width="14.0797pt" 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="M673 297H417L411 270C517 261 522 258 506 183L487 92C476 38 428 19 360 19C207 19 123 132 123 287C123 472 243 631 441 631C557 631 617 583 617 469L647 472C650 545 655 604 658 632C625 643 554 666 467 666C201 666 23 502 23 278C23 90 156 -16 339 -16C410 -16 501 6 569 24C566 43 567 70 573 101L589 183C604 259 607 262 667 271L673 297Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,8.827,3.132)"><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> with NL, <object data="https://static.hindawi.com/articles/ijap/volume-2022/9669114/figures/9669114.tab-inline.002.svgz" name="9669114.tab-inline.002" type="image/svg+xml"></object><svg height="11.8174pt" id="M18" style="vertical-align:-3.1815pt" version="1.1" viewbox="-0.0498162 -8.6359 16.482 11.8174" width="16.482pt" 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="M673 297H417L411 270C517 261 522 258 506 183L487 92C476 38 428 19 360 19C207 19 123 132 123 287C123 472 243 631 441 631C557 631 617 583 617 469L647 472C650 545 655 604 658 632C625 643 554 666 467 666C201 666 23 502 23 278C23 90 156 -16 339 -16C410 -16 501 6 569 24C566 43 567 70 573 101L589 183C604 259 607 262 667 271L673 297Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,8.827,3.132)"><path d="M498 658H277V626C335 621 342 616 342 579C220 574 46 510 46 330C46 148 226 88 342 86C342 41 334 37 271 32V0H498V32C435 37 427 41 427 86C546 88 723 153 723 337C723 518 550 575 427 579C427 616 434 621 498 626V658ZM342 123C255 129 141 183 141 338C141 489 257 538 342 542V123ZM427 542C512 538 629 489 629 333C629 178 512 129 427 123V542Z"></path></g></svg> with NL, <object data="https://static.hindawi.com/articles/ijap/volume-2022/9669114/figures/9669114.tab-inline.003.svgz" name="9669114.tab-inline.003" type="image/svg+xml"></object><svg height="11.927pt" id="M19" style="vertical-align:-3.291101pt" version="1.1" viewbox="-0.0498162 -8.6359 14.0797 11.927" width="14.0797pt" 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="M673 297H417L411 270C517 261 522 258 506 183L487 92C476 38 428 19 360 19C207 19 123 132 123 287C123 472 243 631 441 631C557 631 617 583 617 469L647 472C650 545 655 604 658 632C625 643 554 666 467 666C201 666 23 502 23 278C23 90 156 -16 339 -16C410 -16 501 6 569 24C566 43 567 70 573 101L589 183C604 259 607 262 667 271L673 297Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,8.827,3.132)"><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> without NL, and <object data="https://static.hindawi.com/articles/ijap/volume-2022/9669114/figures/9669114.tab-inline.004.svgz" name="9669114.tab-inline.004" type="image/svg+xml"></object><svg height="11.8174pt" id="M20" style="vertical-align:-3.1815pt" version="1.1" viewbox="-0.0498162 -8.6359 16.482 11.8174" width="16.482pt" 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="M673 297H417L411 270C517 261 522 258 506 183L487 92C476 38 428 19 360 19C207 19 123 132 123 287C123 472 243 631 441 631C557 631 617 583 617 469L647 472C650 545 655 604 658 632C625 643 554 666 467 666C201 666 23 502 23 278C23 90 156 -16 339 -16C410 -16 501 6 569 24C566 43 567 70 573 101L589 183C604 259 607 262 667 271L673 297Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,8.827,3.132)"><path d="M498 658H277V626C335 621 342 616 342 579C220 574 46 510 46 330C46 148 226 88 342 86C342 41 334 37 271 32V0H498V32C435 37 427 41 427 86C546 88 723 153 723 337C723 518 550 575 427 579C427 616 434 621 498 626V658ZM342 123C255 129 141 183 141 338C141 489 257 538 342 542V123ZM427 542C512 538 629 489 629 333C629 178 512 129 427 123V542Z"></path></g></svg> without NL. (a) <i>xz</i>-plane at 2.4 GHz, (b) <i>xz</i>-plane at 5.8 G, (c) <i>yz</i>-plane at 2.4 GHz, and (d) <i>yz</i>-plane at 5.8 GHz.</div>

International Journal of Antennas and Propagation

fig14

Figure 14

Figure 14: Characteristic Mode-Based Neutralization Line Design for MIMO Antenna 