One example communication device receives a radio frequency (RF) signal. The communication device may include a radio frequency integrated circuit (RFIC) that includes an internal attenuator. The RFIC and other processing circuitry may convert the received RF signal to a baseband frequency to generate a processed complex baseband signal. A digital signal processor of the communication device may determine, based on detection of or lack of detection of distortion terms in a frequency spectrum of the processed complex baseband signal at frequencies corresponding to integer multiples of a symbol rate of a linear modulation interferer, a modulation type of an interferer signal that forms at least part of the processed complex baseband signal. The digital signal processor may also control whether the internal attenuator is enabled based on a received signal strength indication (RSSI) of a desired RF signal and the modulation type of the interferer signal.