Radiosonde for Atmospheric Refractive Index Measurements

An instrument for transmitting a carrier frequency analog of atmospheric radio index of refraction is described. The signal transmitted is received at a remote point through the use of a phase lock type of receiver. It employs a ceramic coaxial cavity, one-half wavelength long, as a sensor, and the nominal operating frequency is 403 Mc. The instrument, when operated with other cavities, offers the laboratory gas dielectric investigator a convenient tool for studying real components of gas dielectrics. Operation can be easily extended to higher frequencies by the use of suitable cavities and solid state multipliers.