Fixed Frequency Beam-Scanning HMSIW-Based Leaky-Wave Antenna Composed of Circular Slots in V-Shape Configuration

Abstract

A new reconfigurable slotted antenna is presented in this manuscript. The proposed antenna is realized on a half-mode substrate integrated waveguide (HMSIW). The beam-steering is achieved using embedded varactor diodes in circular cells. Sweeping the bias voltage causes variations of the phase constant, which leads to the fixed frequency beam-scanning. Each reconfigurable cell includes a circular slot at the top plate and varactor switch, DC block, and RF block at the backside of the structure. The operating frequency is chosen as 28.5 GHz in the support of the upcoming 5G mm-wave communications systems. The proposed antenna beam scans 29° of space by switching among different states at 28.5 GHz. The length, width, and height of the antenna are 67 mm, 48 mm, and 0.32 mm, respectively. The proposed antenna’s main novelties are compactness and electronic beam-scanning capability using a single switch per cell. The measured peak realized gain and sidelobe level (SLL) at 28.5 GHz are 8.2 ± 0.6 dBi and 5 dB, respectively. While the impedance bandwidth of the proposed antenna is 1.5 GHz. A good agreement between measured and simulated results is observed. The discrepancies are investigated through a sensitivity analysis. Fixed frequency beam-scanning capability, compactness, simplicity of the assembly, backward radiation, and slight gain variation of the proposed antenna make it a suitable candidate for blind-spot monitoring and 5G vehicle to everything (V2X) communications.

Keywords

• Antenna
• beam-scanning
• compact
• leaky-wave
• varactor diode