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VSWR to Reflection Coefficient Calculator

This tool converts Voltage Standing Wave Ratio or VSWR to Reflection Coefficient (sometimes referred to as Gamma) ฮ“.

๐Ÿ” Reflection Coefficient ฮ“ to VSWR

Formula

ฮ“ = (VSWR – 1)/(VSWR + 1)

VSWR is a positive number greater than or equal to 1

Background

VSWR (sometimes called standing-wave ratio SWR) is a measure of the impedance match between a feedlineโ€™s characteristic impedance and the attached load. The load can be an antenna or any RF module such as a filter or amplifier. The greater the degree of mismatch the less efficient the design and implementation.

VSWR is often expressed as a ratio to 1. For example, if the VSWR is 1.9 then it is written as 1.9:1.

Within the context of antennas a good value of VSWR is 1.5 or lower. In an ideal situation, the load is perfectly matched to the feedline characteristic impedance, VSWR=1 and using the calculator ฮ“=0. In this case, no signal energy is reflected and all of it is transmitted forward.