Reconfigurable feeding network for GSM/GPS/3G/WiFi and global LTE applications

This paper presents a novel miniaturized reconfigurable and switchable feeding network to cover GSM, GPS, 3G, WiFi and global LET standards. The feeding network consists of four conventional Wilkinson power dividers which can be individually reconfigured in length using PIN diodes switches. By controlling the bias voltages of these PIN diodes, the operating frequency of the proposed design can be converted between four different bands: 600MHz-900MHz, 1.2GHz-1.6GHz, 1.8GHz-2.2GHz and 2.4GHz-2.6GHz. The first frequency band (600MHz-900MHz) is applied to satisfy the applications of LTE US (700MHz), LTE UK (800MHz) and GSM (850MHz, 900MHz). The second band (1.2GHz-1.6GHz) targets GPS L1 (1.575GHz) and GPS L2 (1.227GHz). Different GSM (1800MHz, 1900MHz) and 3G standards (UMTS, W-CDMA, TD-SCDMA and CDMA2000) are located in the third frequency band (1.8GHz-2.2GHz). The last band (2.4GHz-2.6GHz) is used to cover WiFi (2.45GHz) and LTE Europe (2.6GHz). The miniaturized and optimized feeding network exhibits good performance for S-Parameters in each band, which includes low return loss, equal power splitting and suitable insertion loss. Within the simulation environment, three types of PIN diode models were constructed and investigated in order to improve accuracy. The feeding network is implemented on an FR4 substrate. Fabrication and measurement results closely correlate with those obtained during design simulations. The reconfigurable feeding network can be particularly applied to commercial multiband communication systems.