Optical Spatial Filter to Suppress Beam Wander and Spatial Noise Induced by Atmospheric Turbulence in Free-Space Optical Communications

<div>Experimentally signal power <svg height="12.3393pt" id="M202" style="vertical-align:-3.05097pt" version="1.1" viewbox="-0.0498162 -9.28833 22.8315 12.3393" width="22.8315pt" 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="M368 -163L175 271L368 704H302L110 274V268L302 -163H368Z" id="g50-61"></path><glyph.data ascent="3443" descent="-2856" horiz-adv-x="423" vert-adv-y="423"></glyph.data></g><g transform="matrix(.013,0,0,-0.013,5.499,0)"><path d="M622 479C622 589 545 650 400 650H146L140 618C229 609 230 602 215 527L135 132C117 43 112 41 27 32L18 0H305L313 32C213 40 205 44 222 132L251 284L324 262H365C484 269 622 333 622 479ZM528 477C528 356 420 305 344 305C300 305 276 314 259 321L303 554C311 597 313 600 331 606C345 611 361 614 379 614C463 614 528 580 528 477Z" id="g50-81"></path><glyph.data ascent="3443" descent="-2856" horiz-adv-x="640" vert-adv-y="640"></glyph.data></g><g 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method and <svg height="15.4645pt" id="M205" style="vertical-align:-3.7426pt" version="1.1" viewbox="-0.0498162 -11.7219 85.9656 15.4645" width="85.9656pt" 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="M622 479C622 589 545 650 400 650H146L140 618C229 609 230 602 215 527L135 132C117 43 112 41 27 32L18 0H305L313 32C213 40 205 44 222 132L251 284L324 262H365C484 269 622 333 622 479ZM528 477C528 356 420 305 344 305C300 305 276 314 259 321L303 554C311 597 313 600 331 606C345 611 361 614 379 614C463 614 528 580 528 477Z" id="g50-81"></path><glyph.data ascent="3443" descent="-2856" horiz-adv-x="640" vert-adv-y="640"></glyph.data></g><g transform="matrix(.0091,0,0,-0.0091,8.091,-5.872)"><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" 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Advances in Optical Technologies

fig6

Figure 6

Figure 6: Optical Spatial Filter to Suppress Beam Wander and Spatial Noise Induced by Atmospheric Turbulence in Free-Space Optical Communications 