TOP > Report & Column > The Forefront of Space Science > 2009 > Transmitting Information about the Universe via a Small Circuit Space Communications by the Cutting-Edge Radio-wave Engineering Technology
The small (flexibility) can effectively control the large (rigidity)
I believe that you understood that electronic communication technology largely contributes to space technology as discussed above. Without exact knowledge of where these tiny electronic components are installed in a large spacecraft or space station, however, it is hard for you to understand just how crucial they are for space development.
A solar array panel and an antenna are prominent electric equipments on an in-orbit spacecraft such as a scientific satellite. Solar array panel mainly supplies electric power to onboard electronic instruments, while the antenna is required for communications between satellite and the ground, for example, transmitting data collected by onboard sensors to the ground and command signals from the ground to the satellite. Solar panel and antenna are connected to circuit installations or modules assembling circuit elements. Without these circuits or modules, it would be impossible to have both power supply from an electrical source and data communications. Satellite itself would be a large empty body.
In other words, a very small electronic circuit that can flexibly satisfy many requirements plays a critical role in a large, robust spacecraft. This is true for the ground station. Assembry of circuits and modules can fulfill the requirement to track and communicate with a fast-moving satellite. In conclusion, a small flexible one (i.e. circuit) controls a large rigid one (i.e. satellite or ground station).
For the three research areas mentioned above-space communication engineering, space radio-wave science and wireless communication energy transmission-we aim to realize the following tentative research targets: an ultra-small, ultra-high performance sensor and semiconductor integrated circuit; the world’s smallest transceiver with antenna; and an ultra-high speed wireless communication energy network. To advance the R&D of these cutting-edge electronic communication technologies, we are actively cooperating with researchers in Japan and abroad. The cooperation has been made for realization of the ultra-small, light-weight, multi-functional space electronic equipment for satellites or space stations and networks incorporating such electronic equipment. In addition, we are jointly addressing issues of highly reliable space electronic components, payload (maximum volume onboard spacecraft) and so on.
MMIC is a little giant
To realize ultra-small, ultra-high performance sensors and semiconductor integrated circuits, we have to develop high-frequency, high-power, low-noise, and high-efficiency integrated circuits that introduce new-concept semiconductor materials and high-performance devices and can function in microwave, milliwave and terahertz wave. The right of Fig. 3 shows a Monolithic Microwave Integrated Circuit (MMIC) made of gallium-arsenide semiconductor, which provides a relatively high output at 5.8GHz of microwave band. Though the MMIC is around 4mm square in size, we can modify it and produce an ultra-small amplifier for the transmitter, which can be used for the 64m antenna at the Usuda Deep Space Center (UDSC) shown in Fig. 1. We are also considering introducing the currently proposed system-on-chip technology, which would incorporate antenna, high-frequency circuit, control circuit and signal-processing circuit onto a single semiconductor substrate. This technology is also applicable to detection of high-energy particles. We are jointly manufacturing a prototype of X-ray detector that will measure part of particle energy as changes in inductance of a microwave component.