This study is based on resonant wireless power transfer with the type of series to series (S-S) in hope to discuss the status and simplified particular solutions of dual antennas for transmission. The Concentric Flat - Plate (CFP) antenna is used in this study and interaction of electromagnetic waves during transmission makes it difficult to predict the reception result. Analyzing the interaction of two electromagnetic waves during transmission makes it easy to predict the reception result also understand the transmission mechanism clearly. Complex mathematical equations require computer simulations to produce results but solve the analytical solution using in time domain's method. The solutions in this paper can precisely prediction the attenuation using in WPT system based on specific signal frequency working at 13.56 MHz which is included in ISM band. The working frequency is set to the resonant frequency. The result is very useful in WPT system with the result. Compared the results with simulation to demonstrate the solution.