Design of Inner-Layer Capsule Dipole Antenna For Ingestible Endoscope

To design antennas for ingestible wireless capsule endoscope systems, the effects of relative permittivity and conductivity of human body equivalent liquid (HBEL) on the effective electrical length of capsule antenna are investigated by numerical analysis. Three types of capsule dipole antennas, the isolated type, the surface type and the inner-layer type are discussed. The inner-layer capsule dipole antenna having characteristics of both large effective electrical length and small propagation loss is proposed. A design of internal impedance of capsule dipole antenna to obtain maximum received power at 500 MHz is also presented.