Octave band stacked microstrip patch phased array antenna

An antenna array for detecting radiation between a first frequency, having an associated wavelength λ1, and a second frequency that is at least twice the first frequency and having an associated wavelength λ2, the antenna array comprising a plurality of unit cells, each such unit cell comprising:

• a first substrate having a thickness of 0.0203λ1 and a relative permittivity of about 3.5;
• a first ground plane disposed on a lower surface of the first substrate;
• a second substrate disposed over the first substrate and having a thickness of 0.0203λ1 and a relative permittivity of about 3.7;
• an impedance matching network disposed between the first and second substrates, the impedance matching network having an RE port and an antenna port;
• a first via extending from the RF port to an output port of the unit cell;
• a third substrate disposed over the second substrate and having a thickness of 0.0373λ1 and a relative permittivity of about 3.0;
• a second ground plane disposed between the second and third substrates;
• a fourth substrate disposed over the third substrate and having a thickness of 0.0406λ1 and a relative permittivity no greater than about 1.25;
• a lower patch antenna element disposed between the third and fourth substrates;
• a second via extending from the lower patch element to the antenna port;
• a fifth substrate disposed over the fourth substrate;
• and
• an upper patch antenna element disposed on an upper surface of the fifth substrate.