Ground stations used in the backup systems for the communications with the ISS (International Space Station) is now upgraded and improved by NASA.
NASA maintains a ground station system that helps to transmit and receive VHF (Very High-Frequency Radio Waves). VHF1 and VHF2 are the two frequencies used by the system. NASA’s space network is mainly used for communication with ISS that relies on a constellation of data relay satellites and tracking in geostationary orbits.
For audio-only communications with the ISS, VHF1 is used in emergency cases. For communications with Soyuz, VHF2 is used to ensure communications for ISS and Soyuz spacecraft when Russian VHF ground stations are not in range.
Some upgrades are made by NASA to install new software for tracking Soyuz and station and to develop electronic components. New antennas will also be installed at ground stations for concurrent operations in both the frequencies (VHF1 and VHF2).
There are 2 VHF ground stations for NASA- one is at NASA’s AMFC (Armstrong Flight Research Centre) in California and another at Wallups Island located in Virginia. This is to ensure maximum coverage of orbit complex over North America. These are controlled by NASA’s GSFC (Goddard Space Flight Centre). ISS and Soyuz are located in Europe and Asia while Russia’s VHF stations are over across the country itself to ensure proper communications.
Two VHF1 antennas are used by space stations to send and receive the signals. These are situated at the ends of an outpost in Russia. A VHF2 antenna is allocated for all Soyuz spacecraft.
VHF ground stations are to be ensured to remain a capability for emergency communications and backup. This is done by upgrading ground stations. These systems are only to be used during failure of communications in space stations or for emergency onboard in Soyuz. For this, redundancy and ‘belt and suspenders’ approach was added.
Space network allows for the very big transmission of data on the range of hundreds of megabits/sec while audio-only communications are only allowed by VHF system. This helps to ensure a variety of activities which requires a large amount of data. This includes live TV shows and interviews with cosmonauts and astronauts. Activities such as science experiments which are largely data consuming and high definition real-time videos are also included. NASA’s GSFC (Goddard Space Flight Centre) also manages space network that uses TDRS spacecraft. Upgrading the ground stations are inevitable as satellites are on a continuous path of evolution, being faster, better, and smarter.