Application of switchable 4G/5G dual antenna system for laptops

Abstract

This work investigates a switchable 4G/5G dual-antenna system designed for laptops. The dual open-slot antenna structure is straightforward, with a slot width of only 2 mm. Each individual antenna features two different feed sections located in two separate regions between the slots. Port 1 is a direct-feeding design with 3.6 pF chip capacitance, while Port 2 is only a direct-feeding design. When Port 1 is excited and Port 2 is terminated to 50-Ω, the antenna is functional in long-term evolution (LTE) low-band (617–960 MHz) and 5G sub-6 GHz band (3300–5000 MHz). On the other hand, when Port 2 is excited and Port 1 is terminated to 50-Ω, the antenna is functional in the LTE medium/high bands between 1710 and 2690 MHz. The measured isolation consistently exceeded 30 dB, and the efficiency remained above 48% across the entire frequency range. The calculated envelope correlation coefficients derived from the complex E-field radiation pattern measurements were consistently below 0.02. These findings indicate that the system is exceptionally well-suited for applications characterised by integrated metallic environments and a high display-to-body ratio.