A space-based component, such as a satellite, is configured to receive wireless communications from radiotelephones in a satellite footprint over an uplink satellite radiotelephone frequency, and to transmit wireless communications to the radiotelephones over a downlink radiotelephone frequency. An ancillary terrestrial network, that may include one or more ancillary terrestrial components, is configured to transmit wireless communications to, and receive wireless communications from, the radiotelephones over the uplink satellite radiotelephone frequency in a time-division duplex mode. An interference reducer is configured to reduce interference from the wireless communications that are received by the space-based component from the second radiotelephone and/or from the ancillary terrestrial network over the uplink satellite radiotelephone frequency, using the wireless communications that are transmitted by the ancillary terrestrial to, and/or received by the ancillary terrestrial network from, the second radiotelephone over the uplink satellite radiotelephone frequency.