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2 crobolometer integrated with a twin rectangular microstrip patch antenna. This letter demonstrates, for the first time, the use of microstrip dipole antenna structures for the detec- tion of midinfrared radiation. The difference between a printed dipole 2 and a printed microstrip dipole is that the latter is placed a fraction of a free-space wavelength above a metallic ground plane. The presence of the ground plane leads to a better confinement of the electromagnetic fields under the dipole, and thus to a higher antenna quality factor. Furthermore, for the same dielectric spacer thickness, a half-wavelength microstrip dipole has a narrower bandwidth than a rectangular microstrip patch antenna 6 . Infrared antennas are essentially scaled-down versions of their counterparts found in the microwave portion of the electromagnetic spectrum. However, as the frequency of op- eration increases, so does the energy dissipation within the materials involved in the fabrication of the antennas. The typical thickness of the layers that make up an antenna-cou- Ž. pled infrared IR detector is about 100 nm. The physical parameters of such thin layers depend on the details of the deposition conditions. Therefore, the material data available in the literature can only provide a starting point for the design of infrared antennas. Full-wave electromagnetic techniques such as the method Ž. Ž .