Basics Of A Vector Network Analyzer That Every Novice Engineering Student Should Know

Accurate de-embedding of an instrument is crucial to characterize the electrical performance of a component, whether it is a chip, PCB, connector, or cable. A Vector Network Analyzer is perhaps the best instrument to use for measuring because it measures the detailed electrical behaviour of a component at every frequency.

There are two types of network analyzers available in the market- Scalar, and Vector. A Scalar network analyzer is an electronic instrument that measures only the magnitude of the input versus output voltage. The scalar network analyzer is used to measure things like shielding effectiveness, or general filter response. However, these things can be measured with a spectrum analyzer as well. On the other hand, a vector network analyzer measures both magnitude and phase of the same input/output voltage, capturing both the real and imaginary information. This is crucial in matching circuits because it includes the resistance and capacitive/inductive reactants.

The vector network analyzer would help the engineers to handle signal integrity measurement and calibration for high-speed boards. However, a component, or device under test does not allow itself to be measured directly and it becomes essential to mount it on a fixture for getting connected to the Vector Network Analyzer. Subsequently, the effect of the fixture needs to be removed i.e. de-embedded in order to measure the true electronic behaviour of the device that is being tested.

The user interface in a vector network analyzer is a bit scarce, and it comes along with cursor buttons along the bottom of the display. The top knob and two cursor buttons allow the user to choose which field has to be changed and set the values for same. The Mode (M) button represents the type of measurement. The unit comes calibrated or it can be recalibrated any time using a set of open, short, or 50-Ω calibration standards.

A vector network analyzer is used to make reflection measurements to ensure the efficient transfer of power. This is because, when there is a reflection of energy, less energy would get transmitted, leading to inefficient usage of expense Representative Fraction (RF) energy and resources. Another reason being, instruments like amplifiers can be damaged due to large amounts of reflection in energy .

Whether an engineer is installing or maintaining cables and antennas, troubleshooting network coverage up on a tower, a vector network analyzer can be easily trusted. The engineers need to keep in mind that it takes some training and sound knowledge about the network analyzer to operate it. However, once the art is mastered it becomes pretty much easier to work with one.