An airborne radar and wave propagation laboratory

The Naval Research Laboratory has instrumented an R5D aircraft as an airborne radar and wave propagation laboratory. The installation includes four radar systems (with frequencies ranging roughly from 1 to 10 kMc), associated radar recording and calibration apparatus, and an extensive meteorological instrumentation for measurement of related atmospheric conditions. All radars operate synchronously from a centralized control. The antennas, along with the transmitter-receiver systems, allow the transmission of vertical, horizontal, or circular polarization, with simultaneous reception of the transmitted polarization and its orthogonal component. This aircraft is intended for investigations in two general fields, back-scattering (radar) and wave propagation. In the radar field, it may be used for the determination of the back-scattering properties of individual targets or of area-extensive targets such as ground, sea, or precipitation. In the propagation field, it may be used as one terminal of a one-way transmission link, such as in investigations of radio ducts and atmospheric scattering.