All 2015 Content
Session
Technical Session VI: Ground Systems and Communications
Abstract
For smallsat ground station owners who are dissatisfied with the traditional and costly way of building stove-piped ground station solutions, why not simply treat the satellite as a member of the IP network on the ground? This solution allows the software on both the ground and satellite to dynamically change to meet the end-user needs, unlike the static approach of ground stations of the past. Using the internet protocol (IP) to implement space to ground communications allows flexible and affordable solutions. Leveraging currently available network stacks in conjunction with existing space communications standards brings the internet protocol to space, allowing standard client/server communications directly with the satellite by extending the ground network to space. Updating the satellite’s software is accomplished by securely copying the software using readily available open source tools, such as secure copy (SCP.) Interfacing with the satellite’s operating system is done using secure shell (SSH.) Software development for the ground station and satellite under this paradigm is just like traditional network software development, taking place at any time during the satellite’s lifecycle. By developing a custom linux network driver, the network stack can be used to route packets to and from the satellite through a modem. The linux server on the ground has an IP address on its network that is on the same subnet as that of the satellite. Network Address Translation, which is built in to linux, can then be used to communicate with the satellite with traditional network programming techniques. Well accepted standards like CCSDS can be used to encapsulate the IP traffic that is transmitted to and received from the satellite. The satellite has built in software that performs the reverse operation of the ground.
Creating an IP Router for Space to Ground Communications
For smallsat ground station owners who are dissatisfied with the traditional and costly way of building stove-piped ground station solutions, why not simply treat the satellite as a member of the IP network on the ground? This solution allows the software on both the ground and satellite to dynamically change to meet the end-user needs, unlike the static approach of ground stations of the past. Using the internet protocol (IP) to implement space to ground communications allows flexible and affordable solutions. Leveraging currently available network stacks in conjunction with existing space communications standards brings the internet protocol to space, allowing standard client/server communications directly with the satellite by extending the ground network to space. Updating the satellite’s software is accomplished by securely copying the software using readily available open source tools, such as secure copy (SCP.) Interfacing with the satellite’s operating system is done using secure shell (SSH.) Software development for the ground station and satellite under this paradigm is just like traditional network software development, taking place at any time during the satellite’s lifecycle. By developing a custom linux network driver, the network stack can be used to route packets to and from the satellite through a modem. The linux server on the ground has an IP address on its network that is on the same subnet as that of the satellite. Network Address Translation, which is built in to linux, can then be used to communicate with the satellite with traditional network programming techniques. Well accepted standards like CCSDS can be used to encapsulate the IP traffic that is transmitted to and received from the satellite. The satellite has built in software that performs the reverse operation of the ground.
