What is Adjacent Channel Leakage Ratio (ACLR)?

Adjacent Channel Leakage Ratio (ACLR) or Adjacent Channel Power Ratio (ACPR) is defined the ratio of the transmitted power on the assigned channel to the power received in the adjacent radio channel after a receive filter.

Each wireless standard has the adjacent channels located at different frequency offsets. For example, according to the 3GPP standard, the ACLR should be no more than -33 dB at the offsets of ±1.6 MHz and no more than -43 dB at the offsets of ±3.2 MHz. CDMA amplifiers involve two offsets (from the carrier frequency) of 885 kHz and 1.98 MHz, and a measurement BW of 30 KHz.

ACLR is also know as Adjacent Channel Power Ratio (ACPR).