This paper presents a novel network architecture for an integrated nanosatellite (nSAT)-5G system operating in the millimeter-wave (mmWave) domain. The architecture is realized adopting a delay/disruption tolerant networking (DTN) approach allowing end users to adopt standard devices. A buffer aware contact graph routing algorithm is designed to account for the buffer occupancy of the nSATs and for the connection planning derived from their visibility periods. At the terrestrial uplink, a coded random access is employed to realize a high-capacity interface for the typically irregular traffic of 5G users, while, at the space uplink, the DTN architecture is combined with the contention resolution diversity slotted Aloha protocol to match the recent update of the DVB-RCS2 standard. To achieve a reliable testing of the introduced functionalities, an accurate analysis of the statistic of the signal to interference-plus-noise ratio and of the capture probability at each mmWave link is developed by including interference, shadowing, fading, and noise. The application of the designed architecture to data transfer services in conjunction with possible delay reduction strategies, and an extension to inter-satellite communication, are finally presented by estimating the resulting loss/delay performance through a discrete-time discrete-event platform based on the integration of Matlab with Network Simulator 3.

This paper presents a feasibility study for a very high data rate receiver operating in the K/Ka-band suitable to future Moon exploration missions. The receiver specifications are outlined starting from the mission scenario and from a careful system analysis. The designed architecture uses a low noise front-end to down-convert the incoming K/Ka-band signal into a $3.7\mathrm{GHz}$ intermediate frequency (IF). For maximum flexibility, a software defined radio (SDR) is adopted for the I/Q demodulation and for the analog to digital conversion (ADC). The decoding operations and the data interface are carried out by a processor based on field programmable gate array (FPGA) circuits. To experimentally verify the above concepts, a preliminary front-end breadboard is implemented, operating between 27.5 and 30 GHz. The breadboard, which uses components off the shelf (COTS) and evaluation boards (EVBs), is characterized by a $46\mathrm{dB}$ gain, a $3.4\mathrm{dB}$ noise figure and a $-37\mathrm{dBm}$ input-referred 1 dB compression point. Finally, a $40\mathrm{Msym}/\mathrm{s}$ quadrature phase shift keying (QPSK) signal is demodulated by means of a commercially available SDR, demonstrating the above concept. The importance of these results is that they have been obtained exploiting a class of miniaturized and low cost microwave integrated circuits currently available on the market, opening the way to a dense communication infrastructure on cislunar space.

This paper presents a theoretical model for estimating the uplink capacity of a communication in a three-dimensional(3D) millimeter-wave (mmWave) scenario. The model is developed considering realistic channel conditions, including path-loss attenuation, shadowing, and angular dispersion, which comply with recent measurement campaigns carried out in mmWave environment. The analysis also incorporates the effects of interference and noise, additionally accounting in detail for the actual shapes of the transmitting/receiving antenna patterns. Analytical expressions for the statistics of the interference power are derived, in order to enable a low-complexity evaluation of the capture probability and of the Shannon capacity for an interfered uplink communication. The conceived 3D mathematical framework, whose reliability is verified by Monte Carlo validations, is used to investigate some insights concerning the application of beamforming in dense mmWave scenarios.