| 摘要 |
<p>A broadband radio frequency (R.F.) directional bridge and a reference load for combination therewith are suitable for R.F. vector network analysis and R. F. time domain reflectometry measurements up to 26.5 GHz in a terminated Wheatstone configuration. The signal path length between the input, reference and test ports of the bridge microcircuit is less than one-tenth of the wavelength at the maximum frequency of operation. The reference load includes high-frequency, intermediate-frequency, and low-frequency loads. In the high-frequency load, a continually-tapered section includes concentric inner and outer elements matching in taper but differing in R.F. material constants, and a stepwise-tapered section includes a number of two-element loads each composed of cylindrical inner and outer elements having matching, and stepwise decreasing, outer and inner diameters, respectively, but differing in R. F. material constants. The intermediate-frequency load is composed of tantalum resistors; the low-frequency load is composed of ferrite beads. </p> |
