A base station can obtain channel quality conditions for mobile devices in a scheduling interval. The base station can identify a channel quality, a target transmission scheme, and a transmission power level for each of the mobile devices. The base station can assign a unique orthogonal CDMA code. The base station can force the mobile devices to transmit K repeated bursts of uplink data such that each of the mobile devices has a rotated phase shift based on the unique orthogonal CDMA code assigned to each of the mobile devices with each of the mobile devices multiplexed on a same physical channel using an overlaid CDMA operation. The base station can process K repeated bursts that are multiplexed on the same physical channel using the overlaid CDMA operation. The base station can separate the mobile devices according to the unique orthogonal CDMA code and use in-phase (I) and quadrature-phase (Q) (IQ) accumulation according to combine the K repeated bursts.