Design of Compact UWB Bandpass Filter with Sharp Rejection Characteristics

摘要

This study presents an Ultra-Wideband (UWB) filter with sharp rejection characteristics at the upper Wireless Local Area Network (WLAN) band. The filter adopts the modified Composite Right/Left-Handed (CRLH) Transmission Lines (TLs), the unit cell of which is theoretically analyzed to derive the design formulas. Subsequently, a UWB bandpass filter is designed using these formulas. The measurement results show that the fabricated UWB bandpass filter has an insertion loss of less than 1.1 dB, bandwidth of 3.1～4.9 GHz and a rejection of more than 50 dB at 5.8 GHz.