Introduction

As discussed in Chapter 2, the MST technique began in part with Woodman and Guillen (1974) after discovery of atmospheric echoes from the troposphere using the Jicamarca incoherent scatter radar in Peru. Following this, recognizing the potential for meteorological applications, several groups set about building specialized radars for low altitude (less than 20 km) application, based broadly on the Jicamarca system. Primary groups who followed this course included a NOAA group in Boulder, Colorado, and a group at the Max Planck Institut für Aeronomie in Northern Germany. The NOAA Aeronomy group developed the so-called “Sunset radar” which was installed close to Boulder, and later a larger system at Poker Flat in Alaska. The Poker Flat system was in part also designed for mesospheric studies. The Max Planck group built a radar in the Harz Mountains, near Katlenburg-Lindau. These were the first VHF instruments designed specifically for meteorological studies.

Later, similar radars were developed by other groups in the UK, Japan, Australia, and various other countries, eventually leading to large networks of such radars. The term “windprofiler” was adopted to describe such radars when used for tropospheric and lower stratospheric (meteorological) wind measurements. One notable development was the construction of the large MU (middle-upper) radar near Shigaraki in Japan. At the time this was a state-of-the-art instrument, and had many important developments incorporated into it.

In this chapter, we will describe some of the details of three radars. One will be the German SOUSY radar in the Harz Mountains, one the MU radar, and the third a lowcost radar (CLOVAR) built in the 1990s in Canada. The objective is not so much to discuss the history of these radars (that was considered in some detail in Chapter 2), but to give more detail about technical developments through the course of evolution of the MST technique. The SOUSY radar was built at a time when personal computers were just starting to be developed, but were of very slow speed. Instruments like the Data General PDP-8 and NOVA mini-computers were just under development; the PDP-8 was developed around 1965, and the NOVA came into being in the late 1960s and early 1970s.