Systems, methods, and devices can be utilized to aggregate downlink millimeter wave (mmWave) frequency resources based on various conditions. In an example method, a connection request for downlink data is received from a user equipment (UE). The example method includes determining that a first congestion level of a first mmWave downlink channel is below a first threshold and determining that a second congestion level of a second mmWave downlink channel is below a second threshold. An activation request is transmitted to the UE. The activation request instructs the UE to activate a first antenna corresponding to the first mmWave downlink channel and to activate a second antenna corresponding to the second mmWave downlink channel. At least a portion of the downlink data is transmitted to the UE over the first mmWave downlink channel and the second mmWave downlink channel.