Systems and methods for combining signals from multiple active wireless transmitters are discussed herein. An exemplary system comprises a radio enclosure, a first transmitting RFU, a second transmitting RFU, and a combiner. The first transmitting RFU may be configured to receive a signal, upconvert the signal, compare a phase of the upconverted signal to a predetermined phase value, and adjust the phase of the signal based on the comparison to provide a first phase-adjusted upconverted signal. The second transmitting RFU may be configured to receive the signal, upconvert the signal, compare a phase of the upconverted signal to the predetermined phase value, and adjust the phase of the signal based on the comparison to provide a second phase-adjusted upconverted signal. The coupler may be configured to combine the first and second phase-adjusted upconverted signals to create an output signal and provide the output signal to an antenna for transmission.