Personal Homepage: Gernot Hassenpflug

HAVE been involved in radar and remote sensing research since 1993, working mainly in signal processing applications for ground-based atmospheric radars, but also radiosonde and lidar data processing. My experience also includes some years of SAR data analysis and interferometric modeling. Recently, I joined NICT in Tokyo for boundary layer applications, while continuing collaborative projects with Kyoto University on MST research, particularly radar imaging calibration and algorithm development.

The Research Institute for Sustainable Humanosphere (RISH) at Kyoto University undertakes experimental work using mainly two MST radars: the MUR in Shiga prefecture, Japan and EAR in Sumatera, Indonesia.

The National Institute for Communications Technology (NICT) in Tokyo, where I joined on May 1^st 2007 for an 11-month contract, specializes in hardware development for commercial applications of remote sensing and telecommunications. I will be studying city environment in the boundary layer here.

Follow the links below to explore the range of research activity.

MUR radar imaging

HE Middle and Upper atmosphere Radar (MUR) in Shigaraki, Shiga prefecture, Japan, is one of the most flexible instruments for experimental studies of the atmosphere. In 2004, it was upgraded with 25 digital receivers for coherent radar imaging (CRI) and 5 frequencies selectable over a 1-MHz band for frequency interferometric imaging (FII).

Currently I am investigating the relationship between the wind field seen by Doppler beam swinging (DBS) methods and that seen by spaced antenna (SA) methods. In particular I am interested in the effects of the os-called jetstream on the creation of strong shear layers whose turbulent parts are detected by the MUR radar as bacscatter. A further current paper activity is on maximum entropy methods to invert the imaging problem indirectly based on a priori probability distributions.

EAR radar imaging

HE Equatorial Atmosphere Radar (EAR) in Sumatera, Indonesia, is less powerful than the MUR, but can use 5 frequencies selectable over a 1-MHz band for frequency interferometric imaging (FII). However, the system is plagued by timing problems and phase offsets, such that imaging has not been successful since 2002. Most of the work carried out in imaging has been trouble-shooting.

Since the problems with the EAR are as yet not solved, and RISH has not undertaken any enthusiastic steps to cooperate with Mitsubishi in finding a solution, I am continuing data analysis as a hobby only, returning now and again to data to see whether more error-resistant algorithms may yield better information than the current ones.

lidar observations at Shigaraki

IDAR and radar combined observations, with radiosondes as additional data for wind and atmospheric temperature and humidity, are vital to understand and interpret the data of either instrument, and for calibration. In April 2007 one day of data was obtained when yellow sand from China was particularly heavy.

Further work is being done to calibrate the lidar with existing MUR radar data and radiosonde data (including GPS sonde data which includes the wind field measurement).

Currently I am working from NICT together with Assoc. Prof. Nakamura from RISH, Kyoto University, on data from June 2006, and a paper is expected to be completed by the end of the summer of 2007.