Mismatch an antenna and energy bounces back. Watch the incident and reflected waves combine into a standing wave, and see the VSWR every RF engineer chases toward 1:1.
Transmission Line & VSWRLive
impedance matching · reflections
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When a transmission line meets a load that does not match its impedance, part of the wave reflects. Incident and reflected waves combine into a standing-wave pattern measured by the VSWR. A perfect match (RL = Z₀, XL = 0) gives VSWR 1 and no reflection — the goal of every antenna and RF design.
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How it works
When a transmission line is terminated in an impedance different from its characteristic impedance, part of the wave reflects. The reflection coefficient sets the voltage standing wave ratio (VSWR) and return loss. A perfect match produces no reflection and VSWR of 1 — the target of antenna tuning and impedance matching.
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