Development of transportable atmospheric radar

We are developing small-sized transportable atmospheric radars (wind profiling radars) which mainly observe the lower atmosphere. Their results are also used by the Atmospheric Radar Network, WINDAS, of Japan Meteorological Agency.

Simultaneous observations of atmospheric turbulence with UAV and the MU radar

Turbulence mixing is an important process that contributes to the vertical transport of heat and substance. The MU (Middle and Upper atmosphere) radar is the atmospheric radar located at Shigaraki, Koka, Shiga Prefecture, has the center frequency of 46.5 MHz, the antenna diameter of 103 m, and the peak output power of 1 MW. We aim to elucidate the atmospheric turbulence based on Japan-USA-France international collaborative research, ShUREX (Shigaraki, UAV-Radar Experiment) campaign using simultaneously small unmanned aerial vehicles (UAVs) and the MU radar.

Observations using light

We conduct atmospheric observations using the latest optical devices such as lidars which irradiate the laser to the sky, and all-sky imagers which detect weak light emission of the upper atmosphere with a high sensitivity CCD and examine the horizontal structure of the atmosphere.

Development of RASS (Radio Acoustic Sounding System)

We have developed a state-of-the-art remote-sensing system called as Radio Acoustic Sounding System (RASS) to measure continuous temperature profile. We are also developing a RASS system using parametric speakers.

Development of MU radar adaptive clutter suppression system

Strong clutter echoes from a hard target such as a mountain, building, or airplane sometimes cause problems of observations with atmospheric radars. We are developing the techniques to reject or suppress such ground clutter echoes using NC-DCMP (Norm Constrained- Directionally Constrained Minimum Power) method, which makes null toward the direction of the clutter. We develop the techniques to suppress airplane echoes using the airplane position received by ADS-B (Automatic Dependent Surveillance-Broadcast).

Equatorial Atmosphere Radar Observations

In the equatorial region, cumulus convection is actively excited by strong solar radiation heating, solar energy is carried to the whole Earth's atmosphere by circulation and wave motion driven and excited by them. Especially the Indonesian region is the most active region of cumulus convection activity and it has been generating large year-to-year fluctuations, which have great influence on global environmental change through El Nino etc. We are conducting observational research using mainly Equatorial Atmosphere Radar in West Sumatra.

Development of imaging observation system using equatorial atmospheric radar

The Equatorial Atmosphere Radar can be operated in the frequency domain imaging mode. But since it has only one receiving channel, the spatial domain imaging is impossible. To conduct multi channel observation using the EAR. we develop the digital receiver using software defined radio.

Development of Equatorial MU radar system

The Equatorial Atmosphere Radar has 1/10 transmission power compared with the MU radar, so its sensitivity is insufficient to observe the mesosphere and the ionoshepre (in IS mode). Since the EAR has only one receiving channel, spatial domain imaging observations are impossibile. In order to further advance the elucidation of the structure and motion of the atmosphere, we are proposing the establishment of "Equatorial MU radar" which has the same sensitivity and function as the MU radar.