Acoustic Source Localization under Variable Speed of Sound Conditions

<div>Collaborative approach for source localization in an asynchronous distributed sensor network with <svg height="8.68572pt" id="M248" style="vertical-align:-0.0498209pt" version="1.1" viewbox="-0.0498162 -8.6359 7.31558 8.68572" width="7.31558pt" 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="M541 160L512 170C485 116 462 88 439 67C411 41 376 35 318 35C272 35 238 37 224 48C207 61 205 85 212 121L290 533C305 611 308 615 391 622L397 650H139L133 622C217 615 221 612 206 533L126 118C111 41 103 34 23 26L17 0H474C489 31 528 124 541 160Z" id="g113-77"></path></g></svg> nodes (adapted from [<a href="/journals/wcmc/2017/9524943/#B7">7</a>]). GCC: generalized cross correlation, TDOA: time-difference-of-arrival, and <span class="nowrap"><svg height="19.0046pt" id="M249" style="vertical-align:-6.4385pt" version="1.1" viewbox="-0.0498162 -12.5661 15.9156 19.0046" width="15.9156pt" 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="M471 456L444 459C426 433 414 430 388 430C324 430 270 434 216 434C103 434 51 374 23 338L43 317C96 366 146 380 221 375L154 109C149 86 147 68 147 52C147 4 168 -12 197 -12C240 -12 291 25 334 71L320 96C295 75 268 58 252 58C238 58 227 79 238 138C251 211 272 296 292 372C310 372 332 368 350 368C391 368 421 369 434 371C444 388 455 413 471 456Z" id="g113-241"></path></g><g transform="matrix(.0091,0,0,-0.0091,6.282,-6.049)"><path d="M309 -142C211 -61 151 99 151 271S210 601 309 683L288 710C141 611 75 451 75 272V271C75 90 141 -72 288 -169L309 -142Z" id="g50-41"></path></g><g transform="matrix(.0091,0,0,-0.0091,9.54,-6.049)"><path 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id="g113-47"></path></g><g transform="matrix(.013,0,0,-0.013,40.062,0)"><path d="M113 -12C146 -12 170 11 170 46C170 78 146 103 114 103S58 78 58 46C58 11 82 -12 113 -12Z" id="g113-47"></path></g><g transform="matrix(.013,0,0,-0.013,45.239,0)"><path d="M95 130C70 130 46 113 46 88C46 72 54 64 59 64C93 55 121 33 121 -3C121 -41 93 -68 44 -88L55 -117C117 -98 186 -56 186 22C186 91 131 130 95 130Z" id="g113-45"></path></g><g transform="matrix(.013,0,0,-0.013,50.382,0)"><path d="M541 160L512 170C485 116 462 88 439 67C411 41 376 35 318 35C272 35 238 37 224 48C207 61 205 85 212 121L290 533C305 611 308 615 391 622L397 650H139L133 622C217 615 221 612 206 533L126 118C111 41 103 34 23 26L17 0H474C489 31 528 124 541 160Z" id="g113-77"></path></g></svg>:</span> TDOA-values between microphones <svg height="8.8423pt" id="M251" style="vertical-align:-0.2064009pt" version="1.1" viewbox="-0.0498162 -8.6359 3.66193 8.8423" width="3.66193pt" xmlns="http://www.w3.org/2000/svg" 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Wireless Communications and Mobile Computing

fig12

Figure 12

Figure 12: Acoustic Source Localization under Variable Speed of Sound Conditions 