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Design of A CPW‐FED C‐Shaped Slot Array Antenna for Coal Mine/Tunnel Applications

This article proposes a C‐shaped slot array antenna for coal mine or tunnel communications fed by a coplanar waveguide slot line. Each antenna element has a short‐ended C‐shaped slot pair. Instead of working at the basic mode, in the way that traditional half‐wavelength straight slots do, the proposed C‐shaped slot pair of each element operates at the first high‐order mode to realize maximum bidirectional radiation at boresight. The design procedure is generalized, and some influential parameters are studied. A four‐element C‐shaped slot array antenna sample is designed, fabricated, and measured. The measured impedance bandwidth for |S11| ≤ −10 dB is 230 MHz (2.37 GHz to 2.60 GHz), and the measured in‐band maximum gains lie in the range of 9.0–11.1 dBi. The measured bidirectional radiation patterns remain stable without main beam tilting across the 2.4‐GHz WLAN band. The measured and the simulated results show good agreement. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1784–1789, 2013