An apparatus comprises: a first plurality of first radio frequency chains; a second plurality of second radio frequency chains, the first radio frequency chains being configured to produce wider side-band emissions than the second radio frequency chains; at least one antenna array comprising antenna elements, each of a first plurality of the antenna elements being coupled with a corresponding one of the first plurality of first radio frequency chains, the first plurality of first radio frequency chains being configured to cause transmissions predominately in a first band within a channel, each of a second plurality of the antenna elements being coupled with a corresponding one of the second plurality of second radio frequency chains, the second plurality of second radio frequency chains being configured to cause transmissions predominately in at least one second band within the channel.