A wireless communication network serves User Equipment (UEs) over Multiple Input Multiple Output (MIMO) layers. A primary access node wirelessly serves the UEs over a primary amount of MIMO layers in a primary radio channel having a primary channel size. A secondary access node wirelessly serves the UEs over a secondary amount of MIMO layers in a secondary radio channel having a secondary channel size. The primary access node selects a new primary channel size and a new secondary channel size based on the primary amount of MIMO layers and the secondary amount of MIMO layers. The primary access node wirelessly serves the UEs over the primary amount of MIMO layers in the primary radio channel having the new primary channel size. The secondary access node wirelessly serves the UEs over the secondary amount of MIMO layers in the secondary radio channel having the new secondary channel size.