The actual frequencies (uplink and downlink) used inside the frequency range are determined by the ARFCN. … Frequency Bands. GSM 850T-GSM810ARFCN128 through 251350-425Uplink (UL) Formula (MHz)FUL(n) = 824.2 + 0.2*(n-128)FUL(n) = 806 + .2*(n-350)Downlink (DL) Formula (MHz)FDL(n) = FUL(n)+45FDL(n) = FUL(n)+45Frequency Bands – Keysight RFMW Sitemap rfmw.em.keysight.com › rfcomms › refdocs › gsm › gen_bse_cell_band