Traveling-wave antenna

A method for detecting objects beneath or disposed in biological tissue, comprising:

• providing a Vivaldi antenna configured for use in a tissue sensing adaptive radar (TSAR) system;
• and
• using the TSAR system to detect an object beneath or disposed in said biological tissue;
• wherein the Vivaldi antenna comprises:
• ground and conductor electrodes each having a flared contour and configured to cooperatively emit radiation in a selected propagation direction, said ground and conductor electrodes being separated by one or more dielectric substrates;
• and
• a dielectric director configured to at least partially focus said radiation in said selected propagation direction, arranged at least partially between said ground and conductor electrodes.

An antenna, comprising:

• a plurality of planar ground conductors each having a feeding line ground plane;
• a planar conductor electrode having a signal conductor on a feeding line;
• a connector for connecting said ground conductors and said conductor electrode to an external assembly capable of transmitting or receiving electromagnetic energy;
• and
• a director, disposed in an area between where a first ground conductor and a first conductor electrode curve away from one another;
• wherein said planar ground conductors and said planar conductor electrode are separated by one or more dielectric substrates;
• and
• wherein said director is formed of a material having a dielectric permittivity that is higher than a dielectric permittivity of said one or more dielectric substrates.