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This work aims at verifying an innovative approach for link-design optimization of deep-space missions working at Ka band. The presented approach exploits a weather forecast (WF) model coupled with a radiopropagation model to maximize data-transfer during a Ka-band downlink transmission. First, we exploit radiosounding data to tune the WF model on the geographical site of interest. As second step, we use microwave radiometric measurements to verify both WF and radiopropagation models. A final goal is obtained applying the WF-based approach to optimize the link and then computing the yearly data return on the basis of the actual atmospheric scenario measured by the microwave radiometer. On a test period of three years of transmission, WF-based approach provides a gain, in terms of yearly received data-volume, of about 15% up to 24% if compared to traditional link-design techniques. This gain is combined with a corresponding reduction of yearly lost data. These interesting results make the WF-based approach an appealing alternative for deep-space applications.

The European Space Agency (ESA) is today autonomously flying three interplanetary missions: Rosetta traveling to the comet Churyumov-Gerasimenko and the two orbiters Mars Express and Venus Express. The capability of supporting these and future deep-space missions is the consequence of a farsighted decision taken in 1996 to expand the ESA network of 15-m tracking antennas into the deep-space domain. The ambitious plan to provide around-the-clock coverage to all ESA interplanetary missions is almost completed: two deep-space antennas, located in New Norcia (Australia) and Cebreros (Spain), have been in operation since 2002 and 2005, respectively, while a third antenna is planned for 2011. This paper presents the two existing antennas starting from the underlying system requirements originated from the Rosetta mission, which was the most demanding in terms of required performance. The selected architecture is then described, followed by a detailed discussion about the critical performances that play a major role in deep-space support and the associated design issues.

NASA's Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft has embarked the Massachusetts Institute of Technology (MIT) Lincoln Laboratory’s (LL) Lunar Lasercom Space Terminal (LLST) as a secondary payload and part of the Lunar Laser Communications Demonstration (LLCD) experiment. The LLST was operated on four out of every seven days for one month during the commissioning phase of the LADEE spacecraft in lunar orbit, and then again for a shorter period of time, after the end of the primary scientific mission. ESA's Optical Ground Station (OGS) on the Canary island of Tenerife was one of two secondary participating ground stations – together with JPLs Table Mountain facility – involved in the experiment. We present, from ESA's perspective, the Lunar Optical Communications Link (LOCL) project including first results and lessons learned of the short-duration experiment using the OGS. The success of LOCL is of strategic importance for ESA for the development of future optical communications over "deep-space" distances.

Deep space exploration is aimed at acquiring information about the solar system and a significant communication capacity has to be planned for such very large distances. The concept of the RadioMeteorological Operations Planner technique (RadioMetOP) is described together with its main modelling components and objectives. Numerical results, in terms of received frame data using a statistical estimation methodology, is also illustrated using the BepiColombo mission as a baseline example. Preliminary results, using raingauge data and radiometeorological forecast simulations, are discussed taking the fully-adaptive bit-rate test case as a benchmark.

This paper describes the techniques currently in use and those proposed for a precise estimation of the Earth troposphere path delay for Deep Space probe tracking purposes. The different proposed techniques could be selected according to the to the mission goals and tracking accuracy requirements. In this paper, they are sorted by an increasing accuracy but also level of complexity.