DIELECTRIC MEASUREMENTS ON HIGH-Q CERAMICS IN THE MICROWAVE REGION

The postresonator method proposed by Hakki and Coleman for the measure ment of dielectric properties of solids in the microwave region is ree xamined. Based on the experiments performed around 10 GHz, the limitat ions of the method in loss determination for materials with tan delta < 5 x 10(-4) are outlined. Alternative techniques for studying high-Q materials are described. Loss measurements performed on well-prepared ceramics have been used to draw comparisons among these techniques. So me of the experimental findings are new and are reported for the first time.