The primary objective is to design a covert (low probability of interception/detection) point-to-multipoint wireless communication system with a country-wide coverage ability. For such coverage, a geostationary communication satellite transponder acts as a relay (i.e., using the bent pipe principle for amplifying the received signal, frequency translation and forwarding). Adopting generalized multi-carrier schemes with specified correlation properties and low peak-to-average power ratio (PAPR) ensures that the forward and reverse links align with the design specifications of this FDD system. Real-time demonstrations over the COTS (Commercial Off-the-Shelf) platform, which includes FPGA+SDR as each node, validate the efficacy of the waveform choices and receiver algorithms. Even with estimated timing, frequency offset, and channel estimates, a coded block error rate of 10-3 was achieved at -15dB SNR in the presence of 30 other co-channel signals.