Sinc Interpolation for Further Improvement in Frequency Estimation Using Three DFT Samples

<div>DFT magnitudes <span class="nowrap"><svg height="14.7625pt" id="M57" style="vertical-align:-5.47417pt" version="1.1" viewbox="-0.0498162 -9.28833 58.1326 14.7625" width="58.1326pt" 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="M162 -163V703H101V-163H162Z"></path></g><g transform="matrix(.013,0,0,-0.013,3.419,0)"><path d="M748 650H522L515 622L546 617C580 611 587 604 565 575C518 513 469 451 419 393C376 474 349 534 330 580C318 609 325 612 361 618L383 622L392 650H151L144 622C214 616 224 612 257 543L360 327C270 218 187 124 159 95C106 40 92 34 26 28L17 0H252L259 28L236 31C189 37 188 47 209 78C249 136 308 210 377 294L478 79C494 44 487 37 449 32L418 28L409 0H673L680 28C596 34 591 39 554 116L436 361C526 469 574 521 604 553C659 612 669 614 739 622L748 650Z"></path></g><g transform="matrix(.013,0,0,-0.013,13.364,0)"><path d="M290 -163V-135C183 -126 181 -122 181 -44V583C181 662 184 666 290 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290C481 165 381 37 305 37C280 37 249 56 235 71L302 395C328 399 353 402 372 402C427 402 481 378 481 290Z"></path></g><g transform="matrix(.013,0,0,-0.013,33.18,0)"><path d="M535 230V280H323V490H265V280H52V230H265V-3H323V230H535Z"></path></g><g transform="matrix(.013,0,0,-0.013,43.716,0)"><path d="M384 0V27C293 34 287 42 287 114V635C232 613 172 594 109 583V559L157 557C201 555 205 550 205 499V114C205 42 199 34 109 27V0H384Z"></path></g><g transform="matrix(.013,0,0,-0.013,49.956,0)"><path d="M226 -163V703H56V676C162 667 165 662 165 584V-43C165 -122 162 -126 56 -136V-163H226Z"></path></g><g transform="matrix(.013,0,0,-0.013,54.441,0)"><path d="M162 -163V703H101V-163H162Z"></path></g></svg> vs. actual bin frequency in the absence of noise.</div>

Journal of Sensors

fig2

Figure 2

Figure 2: Sinc Interpolation for Further Improvement in Frequency Estimation Using Three DFT Samples 