Space Network Ground Segment Sustainment (SGSS)

The Space Network Ground Segment Sustainment (SGSS) project manages critical upgrades to space communications infrastructure. These upgrades will modernize the Space Network ground stations and improve many of its capabilities.

SGSS’s upgrades will enable increased customer data rates and volume. This means larger amounts of data can be transmitted more quickly. As technology improves, we are able to gather much more data, for example, capturing images from space with higher resolutions. This enables the scientific community to perform more in depth research, but the capability becomes even more useful if we are able to get that data to the community faster. The upgrades will improve data quality, which means there will be fewer errors during data transmission meaning missions won’t have to deal with data gaps. The upgrades will improve customer coverage, so that missions can stay in contact with their spacecraft more frequently. The upgrades will also reduce maintenance requirements, and extend the system’s longevity, making it more cost effective to operate, and ensure the Space Network will remain a viable communications network for many more years.

An upgrade of this magnitude while simultaneously maintaining operational viability has never before been performed.

SGSS upgrades will ensure that more of the ground antennas are available to TDRS under a wider range of conditions, thus decreasing downtime of the ground terminals. Three antennas that currently only have Ku-band capabilities will receive S-band upgrades. Ku-band radio signals have high bandwidth allowing large amounts of data to be transmitted at a time. However, the signals have a relatively narrow field of view and antenna pointing must be very precise in order for the signal to reach its destination. Ku-band signals can also be scattered by atmospheric conditions such as rain. S-band frequencies have a lower bandwidth, but have a wider field of view, requiring less pointing precision, and are much less affected by atmospheric conditions. S-band frequencies can be used if Ku-band signals are interrupted, ensuring communication between TDRS and the ground continues.

Additionally, modern programming languages will be used to replace older, custom-written software to reduce upkeep, and much of the hardware will use commercially available equipment to replace old components to make it easier to repair the system.

SGSS is upgrading SN ground stations with modern enterprise-class hardware and software systems, including the use of a significant amount of commercial off-the-shelf technologies and new security measures.

SGSS will convert analog signals to digital signals right at the main mission antennas to improve the quality of data transmissions. Digital signals reduce the potential of deterioration during transit from the antenna to the transmit and receive equipment.

The new infrastructure has the potential to support the next generations of data relay satellites, which may combine both radio frequency and optical communications technology. This will continue the critical communications lifeline to NASA missions for years to come.