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This study describes a design frequency for designing resonant antennas and microwave structures. Antenna design at the center frequency is a common method for designing resonant antennas. When the designers begin an antenna design, they start to fi nd the center frequency by just taking the average of the target frequency-range boundaries. In fact, the dimensions are inversely proportional to the frequency, and directly proportional to the wavelength. This paper explains that the frequency of the center wavelength must be used as the design frequency. [ABSTRACT FROM AUTHOR]

Radiation from a cavity-backed annular slot array antenna fed by a coaxial probe is studied. The Hankel transform and mode-matching techniques are utilized too obtain a solution in convergent series. A prototype antenna was fabricated and its characteristics were measured at C-band to verify the accuracy of our approach. [ABSTRACT FROM AUTHOR]

CdTe-n+-GaAs heterojunction diodes for room-temperature nuclear radiation detectors have been developed and demonstrated. The heterojunction diode was fabricated by growing a thin n-type CdTe buffer layer followed by the undoped p-like CdTe layer of about a 100 µm thickness on the n+-GaAs substrates using metal-organic vapor phase epitaxy. The diode detectors exhibited good rectification property and had the reverse leakage currents of a few µA/cm² at 40 V bias. The detector clearly demonstrated its energy resolution capability by resolving the 59.54 keV gamma peak from the 241Am radioisotope during the radiation detection test. [ABSTRACT FROM AUTHOR]

Portable devices operating without batteries are sometimes desired in wireless applications such as RFID (Radio Frequency Identification) and telemetry. A novel circularly polarized shorted annular ring-slot rectenna (rectifying antenna) on a 0.5 mm thick flexible microwave laminate is proposed for the powering of these devices. Output dc voltage of 1.3 V and axial ratio of 1.5 dB were measured when 32 dBm microwave power was transmitted at 5.8 GHz over a distance of 2 m. Comparing the results with a rectenna designed on a thick rigid laminate, similar performance was observed. [ABSTRACT FROM PUBLISHER]

Presents the table of contents for this issue of the periodical. [ABSTRACT FROM AUTHOR]

Presents a study which discussed a method of analysis for an annular slot radiating on a dielectric half-space. Purpose of studying slot antennas; Results.