As　technology　continues　to　evolve,　cellular　positioning　plays　a　more　and　more　important　role　for　indoor　communication　scenarios,　especially　for　the　Industrial　Internet　of　Things　(IIoT)　and　sidelink,　which　requires　high-precision　positioning,　intelligent　connectivity,　and　so　on.　This　paper　mainly　discusses　the　performance　comparison　of　two　delay　estimation　algorithms,　which　are　based　on　the　peak　search　in　time　domain,　and　phase-time　shift　in　frequency　domain.　The　first　algorithm　has　high　precision,　but　the　operation　is　complex,　and　the　second　algorithm　has　low　complexity,　but　the　performance　is　affected　by　noise.　To　improve　the　estimation　accuracy,　the　impact　of　FFT/IFFT　point　number　is　evaluated　to　support　IIoT　and　sidelink　operation　with　rigorous　positioning　requirements.　©　2023　IEEE.