Calibration-grade fixed terminations, or loads, are precision low VSWR standards designed for VNA calibration. Depending on the model, fixed terminations can be suitable for fullband or lowband one-port Z0 calibration and/or full two-port isolation calibration.
A sliding termination (or sliding load) consists of a precision, movable, tapered termination in a highly accurate, air dielectric transmission line.
These instruments are basic tools for precision microwave measurements. One general application is "load separation" measurements in which the reflection from the terminating element can be separated from that of the test device. Load separation using sliding loads is a key element in the calibration of vector network analyzers (VNAs). The technique is also used in the measurement of the reflection from two-port devices, particularly "non-insertable", (e.g., waveguide-to-coax adapters, and the directivity of directional couplers).
Shielded, coaxial open circuit terminations ("opens") are used in the calibration of both scalar and vector network analyzers (SNA and VNA, respectively). In both applications, they are used to provide a nominal 180 degree phase offset from a compatible reference short circuit over a broad range of frequencies.
Precision or reference air lines are air-dielectric transmission lines with highly accurate dimensions that can be used in measurement and calibration applications as fundamental impedance standards and to establish reference positions for measurements.
Maury offers bead supported and beadless connectors in air lines using 1.85mm,2.4mm, 2.92mm, 3.5mm, 7mm and type N. Beadless lines offer better impedance and electrical length accuracies and lower VSWR, while beaded lines offer greater convenience.
Precision standard mismatches are fixed coaxial terminations which are used to introduce a known VSWR into a 50 ohm transmission system. These mismatches are extremely useful in a wide variety of applications and are quick and easy to use. They can be used to calibrate swept reflectometers, verify network analyzer calibration, establish impedance references in TDR measurements, etc.