[Institute of Space and Astronautical Science (ISAS)] The Forefront of Space Science: Honeycomb-structured Weight-saving High Gain Planar Antennas Installed on Hayabusa 2

The asteroid explorer “Hayabusa 2” was launched on 3 December. This paper will introduce the high gain planar antennas lightened with the use of honeycomb structure which is hexagonal just like a honey comb. Additionally, we will also talk about the synthetic aperture radar system for small satellites which is currently under development with the same honeycomb structure.

High Gain Planar Antennas Installed on Hayabusa 2

Figure 1 shows the illustration of Hayabusa 2. The two disk-shaped objects installed on the upside of its body are the high gain planar antennas. One is the X-Band (8.4GHz) antenna which is also installed on the Venus Climate Orbiter “AKATSUKI” launched in May 2010. Another one is the Ka-band (32.0GHz) antenna. To make the gain of the antennas higher and increase transmission speed, the Ka-band which is of higher frequency and the X-Band which is adopted in many earth stations are used as a combination.

Diameters of both antennas are around 90cm, but about 1kg of weight was saved with the use of honeycomb structure in waveguides for radio waves.

Figure 1. The asteroid explorer “Hayabusa 2” Of the two circular plate installed on the upper surface of the explorer body, the left is the Ka-band(32.0GHz) antenna and the right is the X-Band(8.4GHz) antenna.