RF filter measurements | RF filter testing method

This page on RF filter testing and measurement describes various RF filter measurements performed during RF filter testing methods or procedures.

RF Filter testing and RF filter measurements

The RF filter can be constructed either using analog components or using RF transmission line concepts such as microstrip, cavity, stripline etc. Before filter is designed, appropriate L, C and R components are choosen with higher precision. This will provide desired characteristics and frequency response with minimum deviation from the expected results. LCR bridge is used to measure values of L, C and R. The resistance and capacitance can also be measured using digital multimeter.

The RF filter Specifications are as follows. These are the RF filter measurements which are to be measured.
• Frequency Range
• Insertion loss
• Out of Band Rejection
• Bandwidth
• Return Loss or VSWR
• Shape Factor
• Ripple
Refer RF Filter terms>> which describes all these RF filter terminologies.

RF Filter test setup

RF Filter test setup

Following are the test equipments or tools used for RF filter testing.
• LCR Bridge
• Spectrum Analyzer
• Vector Network Analyzer (VNA) or Scalar Network Analyzer (SNA)
• Oscilloscope

• The figure depicts test setup using spectrum analyzer.
• First do calibration taking into account RF cables and RF connectors required to connect the DUT (i.e. LPF or BPF etc.).
• After the thru calibration is done, connect the DUT in between and view the frequency response on the screen.
• This will provide insertion loss at different frequency of interest.
• Set the frequency range/BW/Span according to the technical specifications of the RF filter.
• Perform other measurements after doing the test setup accordingly.

RF Filter Related Links

RF Filter calculator
Microstrip based RF Filter design
RF filter manufacturers
RF filter applications
RF filter selection guide
RF filter terminologies


stripline basics and types
Microstrip line variants
Slotline basics and types
Finline basics
CPW(Coplanar Waveguide) basics
Types and basics of coaxial line
Types and basics of transmission line
RF Terms-Useful for RF design and testing.
RF-This page describes what is RF

RF and Wireless Terminologies