General Description
The Image Processing Unit (IPU) receives image data from various experiment equipment in Kibo, encodes those data, then transfers the encoded data to Kibo system lines. The IPU also records experiment image data on the built-in hard disk called Video Record Unit (VRU) when real-time data downlink is not available. The main functions of the IPU are to have various interfaces with Kibo systems and experiment equipment, to receive and decode five channels of independent motion video signals simultaneously, and to record video signals with five VRUs continuously (80GB each). In the future, VRU with 120GB capacity will be launched for the IPU operations.
Specifications
| Item | Specifications | |
| Dimensions | 1/4 DR, W482 x H621 x D660mm | |
| Interface | 1553B, RS422, Video signal, Ethernet, HRDL | |
| In/out data | In | NTSC video, Telemetry, Operation Commands, Digital Still Image |
| Out | H&S Data, Control Commands, Encoded data (MPEG2) | |
| Image Processing | MPEG2, 5ch multiplex, 1ch Decoding | |
| Data Storage | Digital Vtr (x6), Removable HD | |
| Crew I/F | Operation Panel, 12.1 inch LCD | |
Operation
- IPU can be normally operated with ground commands.
- The only crew task in normal operation is to exchange the video tapes.
- There are two paths for downlink from IPU(ISS) to ground. One path is via US relay satellite. The other is via Japanese data relay satellite. (See right figure)
- IPU provides one FDDI channel to downlink which enables downlink operation up to five NTSC video sources.
- During downlink of the video data, IPU can also record those data on video tape.
- MPEG2 parameters are variable at IPU so that the downlink video data can apply to both quick-look purpose and analysis purpose. ( See "Main Subsystem" for more detail information.)
FAQ
Q; Why does JAXA develop IPU?
A; The most critical path at International Space Station is the limitation of the downlink data channel for users. Using IPU, users can downlink up to five video data channels with through FDDI channel, using the compression function of the video data.
Q; If I like to use IPU, what should I do?
A; If you are planning to use JAXA multiuser facilities(GHF, SCOF, PCRF and FPEF), only you have to do is to check that you would like to use IPU in your proposal.
Unless specified otherwise, rights to all images belong to ©JAXA