Description
Printed antennas have many promising applications in communication systems. The ease of fabrication for complex geometries antenna is feasible through printing technologies. Inkjet printed antenna in microwave applications is motivated through higher production output and low-cost fabrication. Furthermore, flexible substrate is available for inkjet printed antenna. Some antennas are studied using polyethylene terephthalate (PET) range from RFID tags to solar cells. Additionally, a 3D printed object is created using an additive process, a process which softens the material to produce layers that shape a structure. The potential of 3D printed applications range from feedhorn to reflector antenna design. The first design is an inkjet printed wideband righthand circularly polarized high gain 4×4 microstrip patch array antenna printed on a PET substrate on top of a foam layer under a PET substrate ground. This design is also implemented using a Rogers 5880 in a 16×16 microstrip patch array antenna but is fabricated as an 8×8 microstrip patch array antenna due to the size constraint. The simulated antenna on a planar surface has an S11 and an axial ratio bandwidth of 7.7GHz to 8.3GHz. The measured antenna has an S11 and an axial ratio bandwidth of 7.6GHz to 8.1GHz. The radiation pattern of the antenna achieves a similarity with the simulation. A conformal structure is studied and compared to the planar structure. It is observed that the S11 parameter has no changes but due to the curvature, the axial ratio and gain drop. This is due to the radiating elements facing in different directions. The second design is a triple mode circular waveguide feedhorn antenna with corrugated chokes. The feedhorn antenna used 3D printer and coated with conductive silver ink and a reference aluminum block milled to compare to the 3D printed antenna. The simulation and prototype antenna designs achieved a S11 bandwidth of 7.45GHz to 7.9GHz. The aluminum and 3D printed feedhorns are tested for radiation pattern quality. The aluminum feedhorn shows close relationship with the simulation results, the 3D printed horn shows a drop-in gain, rise in cross-polarization levels while keeping the pattern beamwidths to the simulated and aluminum feedhorn.
