TRANSMISSION-LINE MEASUREMENT TECHNIQUES

The capabilities and performance of the multimode power-measuring technique have been expanded and improved. New measurement techniques and equipment that have been developed include a directional probe coupler for the measurement of multimode incident power into an arbitrary termination, a technique for determining the individual modes propagating in overmoded waveguide, and techniques for predicting the far-field radiation pattern of overmoded antennas. The addition of new components facilitate accurate frequency tuning and receiver input level adjustment, thereby facilitating operation for more rapid power measurements. All new components and improved measurement procedures were evaluated during two field tests performed in May 1964 and January 1965. The tests were conducted by performing in-guide spectrum-signature measurements on an operational AN/FPS-6 height-finding radar. Both directional and nondirectional in-guide power measurements were performed. The results of these tests showed that the multimode power-measuring equipment can be used in practical field applications to obtain useful information on the spurious-emission characteristics of transmitters. (Author)