What measurement is used to assess antenna performance in terms of standing wave ratio?

Antenna performance can be effectively assessed using the Voltage Standing Wave Ratio (VSWR), which measures the efficiency of power transmission from a transmission line into the antenna. VSWR quantifies the relationship between the voltage of the standing waves created along the transmission line, which occur when there is a mismatch between the load (the antenna) and the transmission line.

When an antenna is properly matched to the transmission line, most of the signal power is radiated by the antenna, resulting in a low VSWR value. A high VSWR value indicates more reflected power, meaning less efficient transmission and potential loss of signal. Therefore, using VSWR as a measurement provides insights into how well the antenna is performing and allows for optimization in terms of matching and efficiency.

The other measurements listed do not specifically assess the standing wave characteristics relevant to antenna performance. Decibel Level tends to indicate signal strength or gain but does not relate to voltage standing waves. Frequency Response measures how an antenna performs across different frequencies but does not directly incorporate standing wave concepts. Signal-to-Noise Ratio evaluates the quality of a signal in the presence of noise but does not address standing wave phenomena or efficiency in the same manner as VSWR does.