After a three year stint at the National Radio Astronomy Observatory in the sixties, where the basis for the book was already laid, he participated in the design, construction, commissioning and operation of the Westerbork Synthesis Radio Telescope. Upon moving to the Max-Planck-Institut für Radioastronomie in Bonn in 1975, Baars was project manager for two highly successful millimeter wave radio telescopes - the IRAM mm-telescope on Pico Veleta, Spain and the Heinrich Hertz Telescope on Mt. Graham, Arizona, USA. Since 1999.  He has been with the European Southern Observatory in Garching, participating with different tasks in the ALMA Project, in particular the evaluation of two prototype submillimeter radio telescopes.

and historical development.- Geometry of reflector antennas.- Electromagnetic theory of the reflector antenna.- Antenna characteristics in practical applications.- Measurement of antenna parameters.- Miscellaneous subjects.- Design features of some radio telescopes.

Reflector antennas are widely used in the microwave and millimeter wavelength domain. Radio astronomers have developed techniques of calibration of large antennas with radio astronomical methods. These have not been comprehensively described. This text aims to fill this gap. It takes a practical approach to the characterisation of antennas. All calculations and results in the form of tables and figures have been made with Mathematica by Wolfram Research. The reader can use the procedures for the implementation of his own input data. The book should be of use to all who are involved in the design and calibration of large antennas, like ground station managers and engineers, practicing radio astronomers and graduate students in radio astronomy and communication technology.