An 1.7–2.7 GHz all-weather broadband High-gain antenna with W-shape reflector for maritime communications

An all-weather broadband high-gain antenna for maritime communication applications is developed in this paper. The proposed antenna, which is devised from the perspective of hydrodynamics, hydrostatics, and electromagnetic performance, is based on combining a wideband high-efficiency electromagnetic radiation structure (WHEMS) and a W reflector to achieve both superior mechanical and electrical performances. The proposed W reflector has a fractional 3-dB gain bandwidth of 150 % for a three-dipole array radiator, which is 53 % and 90 % larger than the gain bandwidth of the classic planar reflectors and the corner reflectors, respectively. To better adapt to the harsh marine environment and its potential IoT demands, the proposed antenna is devised to be light weight, small wind loading, high mechanical strength, small size, low cost, lightning-strike resistant, and consistent coefficient of thermal expansion, without the need of any radome. Two W reflector prototypes are ideated and manufactured from sheets and metal rods, denoted as Antenna I and Antenna II, respectively. Both the antennas realize 10–13 dBi gains in a 45 % bandwidth (1.7–2.7 GHz) with the sidelobe level lower than 12 dB, and a front-to-back ratio larger than 18 dB. The anti-deformation property of the proposed Antenna II is demonstrated to be 3.8 times higher than that of the classic Yagi antenna to be used in an open-ocean environment with a typhoon of force 1.