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In this paper, the main trends of the latest space missions will be outlined, dealing with the advantages of using W-band in space communication systems. In the first part, an overview of the current projects involved in the study of W-band is shown, highlighting the reasons of its future widespread. [1] [2] Currently, the study of W-band is aimed at future applications in three fields: radar applications, space communications to/from Earth, space communications to/from Moon (and beyond). The paper will be focused on W-band applications for space communications systems to/from Moon. Specifically, some simulation related to the use of special modulation techniques over W-band link in order to reach a Gigabit connectivity will be reported. Moreover, a scenario simulations will be carried out dealing with performance analysis of a space communication system working in the W-band.

In the last years EHF (Extremely High Frequency / 30-300 GHz) band is acquiring more and more interest in different fields, such as telecommunications, radar applications and Earth observation, due to advantageous characteristics. Actually, the higher operating frequency with respect to traditional ranges (Ka and lower) allows the achievement of some advantages: no crowding in frequency and hence reduced interference, large bandwidth availability, reduced antenna and electronic components size, and more security in point-to-point links due to smaller beamwidth. Moreover, the increase of frequencies allows the realization of, with respect to lower bands, high resolution applications, as radar images and Earth Observation sensors. However, although W band is an attractive range, it is yet an experimental frontier since no telecommunication mission has been carried out and the technology development at this frequency is still poor, costly and relatively not ready. However, some specific applications, such as radar and radio-astronomy, and just for some frequencies (typically around 94-96 GHz), make an exception. Considering this context, a very significant and preliminary step to useful W band exploitation for terrestrial and satellite telecommunications is represented by the analysis and the validation of a terrestrial link operating at these frequencies with the capability of carrying out transmission/reception experiments. In this frame, the University of Rome, "Tor Vergata" in collaboration with the company Rheinmetall Italy is carrying out an experiment based on the establishment of a W band point-to-point terrestrial link over a distance of some kilometers between the University of Rome "Tor Vergata" (Rome) and Villa Mondragone (Frascati, near Rome). The work aims at showing an overview of the preliminary design of the experimental W band terrestrial air link. It will be very useful mainly for two reasons: firstly, in order to provide a test-bed for evaluating at- - mospheric effects (fading and scintillation, along with amplitude, phase, and polarization distortion) that could compromise the performance of satellite-to-ground communications systems operating at these frequencies; and secondly to verify performance of W band critical technology. The last part of the work investigates the possibility of using, in addition to the traditional approach, Impulse Radio Ultra Wide-Band (IR-UWB) technology for realizing very high bit-rate point-to-point Line Of Sight (LOS) last mile links beyond 60 GHz. This paper will firstly provide a preliminary orographic and propagation analysis of the terrestrial link. Then, a detailed insight into link architecture and transmitter/receiver schemes will be reported taking into account constraints related to the characteristic of the available HardWare (H/W) in Rheinmetall Italy. Finally, an accurate link budget for dimensioning the system in terms of maximum link capability will be reported

In this paper 1,2 , an overview of the evolution towards the second phase (A2) of the WAVE (W-band Analysis and VErification) project is made, and the timeline for the development of a future pre-operative space mission is defined. This includes the definition of a number of advanced preliminary W-band applications such as the utilization of the M-55 Geophysica manned stratospheric aircraft for a number of experiments on the channel propagation in W-band 94 GHz and 82 GHz; the introduction of the LEO nano-satellite mission IKNOW (Inorbit Key-test and validatioN Of W-band) which will be used for a first uplink-downlink satellite channel characterization and in-orbit validation of W-band technology and space qualification processes. These applications are expected to provide the necessary elements towards the realization of the GEO pre-operative payload defined in the phase-A of the project.