표 2. | Table 2. 결합계수의 상대적인 크기에 따른 TX 코일 전압과 전류의 위상차의 변화와 및 그에 따른 RX 공진주파수 찾는 방법 | Changes in the phase difference of TX coil voltage and current according to the relative magnitude of the coupling coefficient and how to find the RX resonant frequency accordingly.

Relative coupling coefficient	Frequency where the TX coil voltage and current phase difference becomes zero	How to find the RX resonant frequency by observing the phase difference of the TX coil
k>kcritical	ωa, ωb (two different positive frequencies)	The lower frequency where the phase difference becomes zero.
k=kcritical	ωa=ωb (only one positive frequency)	The point where the phase difference is the lowest.
k<kcritical	- (two different complex frequencies)