Absolute Radio Frequency Channel Number (ARFCN)

The ARFCN is a number that describes a pair of frequencies, one uplink and one downlink. The uplink and downlink frequencies each have a bandwidth of 200 kHz. The uplink and downlink have a specific offset that varies for each band. The offset is the frequency separation of the uplink from the downlink. Every time the ARFCN increases, the uplink will increase by 200 khz and the downlink also increases by 200 khz.

The given below table summarizes the frequency ranges, offsets, and ARFCNs for several popular bands.

Calculating Uplink/Downlink Frequencies

The following is a way to calculate the uplink and downlink frequencies for some of the bands, given the band, the ARFCN, and the offset.

GSM 900

Uplink = 890.0 + (ARFCN * .2) & Downlink = Up + 45.0

Example:

 Given the ARFCN 72, and we know the offset is 45MHz for the GSM900 band: Up = 890.0 + (72 * .2) Up = 890.0 + (14.4) Up = 904.40 MHz

Down = Up + Offset Down = 904.40 + 45.0 Down = 949.40 MHz