The book describes the principles of construction of feeder paths for main radio relay lines, communication, antenna design, waveguides of rectangular, round, elliptical section and elements of feeder paths. Engineering methods for calculating the parameters of antennas and waveguides, as well as methods for measuring electrical parameters are described. The book is designed for engineers engaged in the development, design and operation of antenna feeder paths for radio relay communication. It can be useful for senior students of communication institutes.