Microwave frequency measurement

Introdaction;
In this blog we study how to measurment frequency of microwave the student must knoe how to measre the frequency.




Microwave frequency can be measured by either electronic or mechanical
techniques.


Frequency counters or high frequency heterodyne systems can be used. Here the unknown
frequency is compared with harmonics of a known lower frequency by use of a low
frequency generator, a harmonic generator and a mixer. Accuracy of the
measurement is limited by the accuracy and stability of the reference
source.


Mechanical methods require a tunable resonator such as an absorption
wavemeter, which has a known relation between a physical
dimension and frequency.


In a laboratory setting, Lecher lines can be used to directly measure the
wavelength on a transmission line made of parallel wires, the frequency can then
be calculated. A similar technique is to use a slotted waveguide or slotted coaxial line to directly
measure the wavelength. These devices consist of a probe introduced into the
line through a longitudinal slot, so that the probe is free to travel up and
down the line. Slotted lines are primarily intended for measurement of the voltage standing wave ratio on the line. However,
provided a standing wave is present, they may also be used
to measure the distance between the nodes, which is equal to half the wavelength.
Precision of this method is limited by the determination of the nodal
locations.

*what did you learn from this blog