Standing wave characteristics
1 Voltage and current are not only 90° out of time. Also differs by 90° in space;
2 The average power is zero, so it cannot be used to transport electromagnetic energy;
3 has antinodes and nodes whose position does not change with time, the distance between the nodes and the adjacent antinodes is λ/2
4 The input impedance is pure imaginary number, and the resistance varies with the length of the transmission line.