Inside the satellite are many instruments, all of which need to communicate with each other. To allow for the communication of information between the instruments on Astro-H, a design concept of a standardized network has been used. This network is known as “Spacewire”, and this is the first time that a major Japanese satellite will make use of such a system. The system works in exactly the same way as any computer does, using internet cables, and each component links up in much the same was a two networked computers or as a computer and a printer do. To realize this system for a network as complicated as the one on Astro-H will be, a forked network hub router is essential.
To actually see if commands can be sent and signals received via the Spacewire, tests were carried out. In the picture, the blue cable is the Spacewire. Inside the rectangular box are various instruments which sent out various pseudo-signals, so that it could be checked whether or not the signals were properly communicated. On the desk, the future Astro-H is displayed.