Co-linear antenna for direction finding

A co-linear direction-finding antenna system, comprising:

• a reference antenna having a reference antenna base;
• a primary antenna that co-linearly opposes said reference antenna, said primary antenna having a primary antenna base;
• said reference antenna and said primary antenna each being an omnidirectional antenna;
• a dielectric sleeve is positioned around said primary antenna;
• said reference antenna and said primary antenna being supported and electrically separated by a ground plane orthogonally positioned therebetween;
• a transmission signal from a source at an unknown location generates a reference antenna radio frequency and a primary antenna radio frequency;
• said dielectric sleeve, having a predetermined thickness related to an azimuthal angle around said primary antenna, and being configured into a spiral shape causes a delayed primary antenna radio frequency;
• said dielectric sleeve leaving an uncovered portion of said primary antenna;
• a means for detecting a time difference of arrival is coupled to said reference antenna and said primary antenna;
• and
• said detecting means monitors and compares said reference antenna radio frequency and said delayed primary antenna radio frequency to establish a time of arrival delay of said delayed primary antenna frequency, provide an Angle of Arrival for said delayed primary antenna frequency and determine said unknown location, without emitting a detectable electronic signature.

A method for determining the unknown location of a signal transmission source with a co-linear direction-finding antenna, comprising the steps of:

• forming a reference antenna with a reference antenna base;
• forming a primary antenna with a primary antenna base;
• aligning said primary antenna to co-linearly oppose said reference antenna;
• forming a dielectric sleeve with a predetermined thickness related to an azimuthal angle around said primary antenna;
• forming a ground plane;
• positioning said ground plane in an orthogonal orientation to support said reference antenna and said primary antenna and electrically separate said reference antenna from said primary antenna;
• allowing said reference antenna to receive a reference antenna radio frequency from said transmission signal source;
• allowing said primary antenna to receive a primary antenna radio frequency;
• causing a delayed primary antenna frequency when said primary antenna radio frequency penetrates said dielectric sleeve;
• monitoring said reference antenna radio frequency and said delayed primary antenna radio frequency with a means for detecting a time difference of arrival;
• comparing said reference antenna radio frequency and said delayed primary antenna radio frequency with said detecting means to establish a time of arrival delay of said delayed primary antenna frequency and provide an Angle of Arrival for said delayed primary antenna frequency;
• and
• determining said unknown location without emitting a detectable electronic signature.