Design of a microstrip dual-frequency diplexer using microstrip cells analysis and coupled lines components

Abstract

In this paper, a microstrip diplexer composed of two similar resonators is designed. The proposed resonator is consisting of four microstrip cells, which are connected to a coupled lines structure. In order to select a suitable geometric structure, first, all cells are assumed as undefined structures where there is a lack of basic information about their geometry and dimensions. Then, an equivalent LC circuit of the coupled lines is introduced and analyzed to estimate the general structure of the resonator respect to a requested resonance frequency. The proposed diplexer is designed to operate at 2.36 and 4 GHz for wireless applications. The insertion losses (S21 and S31) are decreased significantly at the resonance frequencies, so that they are 0.2 and 0.4 dB at 2.36 and 4 GHz, respectively. The designed diplexer is fabricated and measured and the measurement results are in a good agreement with the simulations.

Design and fabrication of a compact microstrip triplexer for wimax and wireless applications

“…This basic structure will be used to design a compact triplexer. An LC model for the coupled lines is selected based on the proposed model in [22,23]. The equivalent LC circuit of the introduced resonator is shown in Fig.…”

Compact metamaterial unit-cell based on stepped-impedance resonator technique and its application to miniaturize substrate integrated waveguide filter and diplexer

“…Diplexers are significant components in designing any modern wireless communication systems . Accordingly, there is a growing demand for realizing and implementing such devices especially in multiservice and multiband communication systems.…”

“…The diplexers can separate the signals from the same input port to two different channels according to the center frequency of each filters. Several diplexer have been proposed on microstrip, SIW and cavity technologies with different techniques . However, there is an essential requirement in the field of compact dimension to achieve high performance diplexers with small size.…”

“…[12][13][14][15][16] Diplexers are significant components in designing any modern wireless communication systems. [17][18][19] Accordingly, there is a growing demand for realizing and implementing such devices especially in multiservice and multiband communication systems. The diplexers are essential components in mobile communication systems because such devices can be used with the transceiver antenna/array to transmit and receive the signals simultaneously at separate frequency bands using single feeder circuit.…”

“…Several diplexer have been proposed on microstrip, SIW and cavity technologies with different techniques. [17][18][19] However, there is an essential requirement in the field of compact dimension to achieve high performance diplexers with small size.…”