GSM Timeslot And Frequency Specifications

These diagrams show how timeslots and corresponding frequencies are allocated in the GSM (Global System for Mobile Communications, originally Groupe Spécial Mobile), DCS (Digital Communications System), and PCS (Personal Communications Service) bands. A GSM Multiframe is the basic unit, and is 120 ms long. There are 26 Frames in each Multiframe, with each Frame being 4.61538 ms long (120 ms/26). Within each Frame are 8 Timeslots at 576.92 μs per Timeslot (577 μs in round numbers). Finally, there are 156.25 Bits per Timeslot, each Bit being 3.69231 μs long.

Tables of all GSM Frequency Bands,GSM Frequency Calculations, andGSM Timing are provided at the bottom of the page.

Data derived from ETSI EN GSM Time Slot, Frame, & Multiframe

GSM Uplink / Downlink

GSM DCS PCS GSM Frequency Bands
T-GSM . .8390. .8DynamicT-GSM . .8420. .8DynamicGSM . .6460. . GSM . .0488. . GSM . .0728. .0DynamicGSM . .0777. . T-GSM . .0851. .0DynamicGSM . .0869. . P-GSM . .0935. . E-GSM . .0925. . , 0-124R-GSM . .0921. . , 0-124T-GSM . .0915. .0DynamicDCS . .01805. . PCS . .01930. . GSM Frequency Calculations
P-GSM 900 1..124890+0.2*ARFCN935+0.2*ARFCNE-GSM 900 0..124975.. +0.2*ARFCN890+0.2*(ARFCN-1024)

935+0.2*ARFCN935+0.2*(ARFCN-1024)

DCS .. .2+0.2*(ARFCN-512) 1805.2+0.2*(ARFCN-512) PCS .. .2+0.2*(ARFCN-512) 1930.2+0.2*(ARFCN-512) R-GSM 900 0..124955.. +0.2*ARFCN890+0.2*(ARFCN-1024)

935+0.2*ARFCN935+0.2*(ARFCN-1024)

GSM .. .6+0.2*(ARFCN-259) 460.6+0.2*(ARFCN-259) GSM .. +0.2*(ARFCN-306) 489+0.2*(ARFCN-306) GSM .. .2+0.2*(ARFCN-128) 869.2+0.2*(ARFCN-128) GSM .. .2+0.2*(ARFCN-438) 777.2+0.2*(ARFCN-438) GSM Timing
Symbol 1 1/8 1/ /13 μs (3.692 μs) /s Burst 156.25 1 1/8 15/26 ms (576.9 μs) 1733/s Frame /13 ms (4.615 ms) 216.6/s 26 Multiframe ms 8.333/s 51 Multiframe .4 ms 4.248/s 52 Multiframe ms 4.167/s Superframe ms 9.803/min Hyperframe 4.2432E+ h:28m:53.760s6.893/day