24-GHz LTCC Fractal Antenna Array SoP With Integrated Fresnel Lens

• Published in: IEEE antennas and wireless propagation letters Vol. 10; pp. 705 - 708
• Main Authors: Ghaffar, F. A., Khalid, M. U., Salama, K. N., Shamim, A.
• Format: Journal Article
• Language: English
• Published: IEEE 2011
• Subjects: Antenna arrays; Antenna measurements; Arrays; Fractal; Fractal antennas; Fractals; Fresnel lens; Gain; Lenses; low-temperature co-fired ceramic (LTCC); system-on-package (SoP)
• ISSN: 1536-1225; 1548-5757
• DOI: 10.1109/LAWP.2011.2161600

A novel 24-GHz mixed low-temperature co-fired ceramic (LTCC) tape based system-on-package (SoP) is presented, which incorporates a fractal antenna array with an integrated grooved Fresnel lens. The four-element fractal array employs a relatively low dielectric constant substrate (CT707, ε r = 6.4), whereas the lens has been realized on a high-dielectric-constant superstrate (CT765, ε r = 68.7 ). The two (substrate and superstrate) are integrated through four corner posts to realize the required air gap (focal distance). The fractal array alone provides a measured gain of 8.9 dBi. Simulations predict that integration of this array with the lens increases the gain by 6 dB. Measurements reveal that the design is susceptible to LTCC fabrication tolerances. In addition to high gain, the SoP provides a bandwidth of 8%. The high performance and compact size (24 × 24 × 4.8 mm 3 ) of the design makes it highly suitable for emerging wireless applications such as automotive radar front end.