Systems and methods for improving bearing availability and accuracy for a tracking filter

A system comprising:

• first and second two-element antennas;
• a processor coupled to the antenna, the processor configured to
• determine an expected maximum antenna element phase-difference value for the elements for the two-element antenna that did not receive a phase-difference value for a target signal source, wherein the determination is based on previously received signals associated with the target signal source and based on elevation information of the target signal source and a predefined maximum antenna element phase-difference value for the respective antenna element pair,
• estimate a phase-difference value for the two-element antenna that did not include a phase difference value based on the expected maximum antenna element phase-difference value and a previously determined predicted bearing value, and
• calculate bearing based on the estimated phase-difference value and a phase-difference value received from the other two-element antenna,
• if only a single phase-difference value is received for one of two two-element antennas;
• and
• an output device coupled to the processor, the output device configured to output information associated with the calculated bearing.

A system comprising:

• a means for determining an expected maximum antenna element phase-difference value for the elements for the two-element antenna that did not receive a phase-difference value for a target signal source;
• a means for estimating a phase-difference value for the two-element antenna that did not include a phase-difference value based on the expected maximum antenna element phase-difference value and a previously determined predicted bearing value;
• a means for calculating bearing based on the estimated phase-difference value and a phase-difference value received from the other two-element antenna, if only a single phase-difference value is received for one of two two-element antennas;
• and
• a means for outputting information associated with the calculated bearing,
• wherein the means for determining determines based on previously received signals associated with the target signal source and based on elevation information of the target signal source and a predefined maximum antenna element phase-difference value for the respective antenna element pair.