Inventors:
Sperry H. Goodman - Kent WA
Gary E. Miller - Auburn WA
James P. Grady - Seattle WA
Assignee:
The Boeing Company - Seattle WA
International Classification:
G01R 2704
Abstract:
A method for determining the phase delay of microwave energy passing through a dielectric material, and for determining values related to the dielectric constant for microwave circuit boards. Phase delay is determined by positioning a pair of transducers adjacent different surfaces of the dielectric material, and injecting microwave energy at a certain frequency along a path through the material from the first transducer to the second transducer. The frequency of microwave radiation is that frequency at which S. sub. 11 and S. sub. 22 for the transducers are both less than a selected amount. Where the dielectric material is a conductively surfaced microwave circuit board, the path through the material is from one edge of the board to another edge through the plane of the board. Microwave circuit boards may be tested by determining values related to the dielectric constant for a plurality of such paths through the board, the paths consisting of a first group of mutually parallel paths and a second group of mutually parallel paths oriented to intersect the paths of the first group. For each path, measurements are made at the frequency or frequencies determined as described above.