Compact conformal wide band antenna for high‐speed WLAN applications

Abstract

This article proposes a compact conformal wideband WiFi antenna based on a wide bandwidth, high-efficiency electromagnetic radiation structure (WHEMS). The concept of the equivalent current model for the WHEMS wideband antenna is described, and an example of a triband WiFi antenna covering 2.4, 5.2, and 5.8 GHz is illustrated. Miniaturization is achieved by cutting the symmetrical structure into half from the original WHEMS model, and wider beam coverage is also obtained. At the same time, the antenna is bent to be conformal with the router system shell and heat sinks, making the antenna more compact. A real award-winning model of a triband mesh WiFi device applying the proposed antenna is shown and tested. The antenna is integrated into a vertically positioned printed circuit board and coexists with a heat sink. The antenna concept and theory, in addition to the simulated and measured results, are provided. The measured | S11 | is lower than −10 dB in the designed wideband (2.4 ~ 2.5 GHz, 5.15 ~ 5.4 GHz, and 5.45 ~ 5.85 GHz). The measured gain at low frequency is about 3 dBi, and the measured gain at high frequency is about 5 ~ 6 dBi. The measured efficiency of the antenna is about 50% to 60%.