Construction method of 30-m-class large planar antenna using electromagnet connection mechanism

Abstract

In order to establish a construction method for a large space structure of several hundred meters or more required by the Space Solar Power Systems (SSPS), it is necessary to carry out a long series of experiments on orbit while gradually expanding the structure size because the current technology level to realize the large space structure is low. If we can carry out the experiments as space use missions like telecommunication, earth observation and so on, we can increase the possibility to carry out the experiments because the cost-effectiveness of the experiments is improved. Therefore, we aim to establish a construction method for a 30-m-class large planar antenna required by a radar to observe precipitation from a geostationary orbit as the immediate target. In order to establish the 30-m-class large planar antenna construction method with high feasibility and expandability for the SSPS, we proposed a method to deploy and connect antenna panel rows one after the other. And we verified feasibility for critical functions of large planar antenna deployment and connection mechanisms used in the proposed method by two step ground experiments. First, we carried out the experiment for the Electromagnet Connection Mechanism (ECM) which is the key device of the antenna deployment and connection mechanisms and confirmed that the basic function concept of the ECM can be realized. Next, we carried out the deployment experiment for panel rows equipped with the ECM and demonstrated the deployment and connection function concept of second and subsequent row panels because these functions are the critical functions.

Oversampling Reflectivity Observations From a Geostationary Precipitation Radar Satellite: Impact on Typhoon Forecasts Within a Perfect Model OSSE Framework

“…The study considered a GPR equipped with a dual-frequency 13.6 GHz Kuband antenna, similar to the one onboard the GPM but with a larger size of antenna, owing to that fact the GPR would be stationed at much greater attitude, and therefore would require a larger antenna to increase horizontal resolution. Based on previous research studies, for example, Joudoi et al (2018), an antenna size measuring 30 m by 30 m with a half-power beam width (−3 dB) of 0.032° was considered, giving horizontal resolution of 20 km at the nadir point. This size of antenna is more than an order of magnitude larger than for GPM or TRMM (∼2 m by 2 m), while the 20-km horizontal resolution is several times larger than current PR satellites, for example, GPM's footprint size is ∼5 km at the nadir.…”