Novel planar diplexer using branch‐line coupler

Abstract

This article introduces a simple and effective design of a planar diplexer with high isolation and flexible frequency selection. The diplexer is composed of two branch‐line couplers and two identical filters. The two couplers are used to split the input signal and also combining the signals in each channel. This leads to signal addition by the couplers and provides very low losses for the diplexer. The wideband matching property of the coupler makes it suitable for both narrow band and broadband applications. A simple, yet effective method is introduced to design each channel separately over wide range of frequencies. The simulated and measured results show satisfactory agreement and indicate low insertion loss (0.9‐1.16 dB) and high isolation (up to 62 dB). The results indicate that the proposed design method may be a promising path to realize diplexers for multi‐frequency communications over a wide frequency range.

A Wideband, Sharp Roll-Off U-Band Diplexer in Suspended Stripline Technology

“…In recent years, various multiplexers with very good functionality have been presented, while most of them are usually narrowband, noncontiguous, or have both disadvantages [13][14][15]. However, some contiguous and wideband multiplexers also have been proposed.…”

A wideband, sharp roll‐off U‐band diplexer in suspended stripline technology

“…In recent years, various multiplexers with very good functionality have been presented while most of them are usually narrowband, noncontiguous, or have both disadvantages . However, some contiguous and wideband multiplexers also have been proposed.…”