Electromagnetic resonance coupler and transmission apparatus

A transmission apparatus comprising:

• an electromagnetic resonance coupler;
• a sender which generates a transmission signal by modulating a radio-frequency wave in accordance with an input signal and sends the transmission signal to the first resonator;
• and
• a receiver which generates an output signal by rectifying the transmission signal output from the second resonator, wherein the electromagnetic resonance coupler includes:
• a first layer including a first principal surface and a second principal surface opposite to the first principal surface, the first layer having a first dielectric constant and a first dielectric dissipation factor;
• a second layer facing the first principal surface of the first layer, the second layer having a second dielectric constant higher than the first dielectric constant and a second dielectric dissipation factor lower than the first dielectric constant;
• a third layer facing the second principal surface of the first layer, the third layer having a third dielectric constant higher than the first dielectric constant and a third dielectric dissipation factor lower than the first dielectric constant;
• a first resonator located between the first layer and the second layer, the first resonator having a planar shape;
• and
• a second resonator located between the first layer and the third layer, the second resonator having a planar shape.