Aspects are provided which allow a UE to manage a number of antennas in adaptive receive diversity (ARD) based on packet error rate (PER). The UE measures a downlink PER and determines a number of antennas for receiving a downlink transmission based on the measured, downlink PER. The UE measures downlink PER during switching from a fallback state to a steady state in an ARD state machine, and the UE changes a size of a fallback window in the ARD state machine based on the measured, downlink PER. The UE also disables switching from the steady state to the fallback state based on the measured downlink PER. As a result, a balance between UE reception performance and power savings is maximized and improved downlink data throughput is achieved.