Contents
What is the voltage component of a standing wave?
The voltage component of a standing wave in a uniform transmission line consists of the forward wave (with complex amplitude ) superimposed on the reflected wave (with complex amplitude ). A wave is partly reflected when a transmission line is terminated with other than an impedance equal to its characteristic impedance .
When is the phase of a wave in a positive phase?
If Φ < 0, then the phase angle of the wave is said to be in negative phase. Similarly, if Φ > 0, then the phase angle of the wave is said to be in a positive phase. Every alternating waveform will have its current , voltage and frequency.
What is the phase difference between voltage and current?
The voltage leads current by 90 0.So the phase difference between voltage and current in capacitor is measured as 90 0. This is exactly opposite to nature of the capacitor.
When is the phase difference between two alternating waves zero?
In-phase: When the difference between phase of two alternating waves is zero, they are said to be “In-phase”. Leading phase: A waveform is ahead of another wave with the same frequency. Lagging phase: A waveform is behind another wave with the same frequency. In LRC circuits, the phase relationship between voltage and current will be
What causes a standing wave in a transmission line?
The reflected power in the transmission line increases the average current and therefore losses in the transmission line compared to power actually delivered to the load. It is the interaction of these reflected waves with forward waves which causes standing wave patterns, with the negative repercussions we have noted.
How is the voltage standing wave ratio ( VSWR ) calculated?
Abstract: Impedance mismatches in a radio-frequency (RF) electrical transmission line cause power loss and reflected energy. Voltage standing wave ratio (VSWR) is a way to measure transmission line imperfections. This tutorial defines VSWR and explains how it is calculated.
How is the VSWR of a transmission line defined?
VSWR is defined from the standing wave that arises on the transmission line itself by: VSWR = |VMAX|/|VMIN| (Eq. 8) Where VMAX is the maximum amplitude and VMIN is the minimum amplitude of the standing wave. With twosuper-imposed waves, the maximum occurs with constructive interference between the incoming and reflectedwaves. Thus: