Novel microstrip branch-line coupler with low phase shift for WLANs

2020

Eng. rev. (Online)

In this paper, a six-channel microstrip diplexer is designed and fabricated. It operates at 0.75/0.85/1/1.25/1.6/1.8 GHz for multi-service wireless communication systems. It consists of two stub-loaded resonators, which are integrated by coupled lines. The channels are close together, which makes the proposed diplexer suitable for frequency division duplex (FDD) schemes. The proposed structure has a compact size of 0.025 λg2 where λg is the guided wavelength calculated at 0.75 GHz. The other advantages of the introduced multi-channel diplexer are the low insertion losses of 1.62/1.27/0.43/0.53/1.26 and 1 dB, as well as good return losses of 26/26/25/25/21.7 and 22 dB at 0.75/0.85/1/1.25/1.6/1.8 GHz respectively. A good isolation of less than 22 dB is obtained between the channels. In order to design the presented diplexer a designing technique is used which is based on the proposing of an equivalent approximated LC model and calculating the inductors and capacitors. To confirm the simulation results, the introduced diplexer is fabricated and measured.

Section: Designing Methodsmentioning

confidence: 99%

A six-channel microstrip diplexer for multi-service wireless communication systems

Fouladi

2020

Eng. rev. (Online)

“…2a-g, where the vertical and horizontal axes show S-parameters in dB and frequency in GHz, respectively. The operating frequency of the designed BLC in (Rezaei, Noori and Hosseini, 2018) is near 2.4GHz which is shown in Fig. 2a.…”

Section: Branch-line Ring and Rat-race Couplersmentioning

confidence: 98%

“…Some structures of the BLCs with their substrate properties and advantages are presented in Table I. As shown, the structures of couplers in (Rezaei, Noori and Hosseini, 2018;Tang and Chen, 2009;Roshani, et al, 2022) are novel. However, the complexity of the proposed structures in (Rezaei, Noori and Hosseini, 2018) and (Roshani, et al, 2022) leads to hard fabrication and subsequently, the possibility of manufacturing error will be high.…”

Section: Branch-line Ring and Rat-race Couplersmentioning

confidence: 99%

“…As shown, the structures of couplers in (Rezaei, Noori and Hosseini, 2018;Tang and Chen, 2009;Roshani, et al, 2022) are novel. However, the complexity of the proposed structures in (Rezaei, Noori and Hosseini, 2018) and (Roshani, et al, 2022) leads to hard fabrication and subsequently, the possibility of manufacturing error will be high. Contrary to these structures, a very simple structure is proposed in (Maheswari and Jayanthy, 2022) In (Lalbakhsh, et al, 2021), six stubs were loaded inside a thin rectangular which led to create a low-pass filtering frequency response.…”

Section: Branch-line Ring and Rat-race Couplersmentioning

confidence: 99%

“…Many BLCs, Ring and rat-race couplers, have been reported using different microstrip structures. In (Chi, et al, 2012) interdigital radial cells (ring structure), in (Salehi, Noori and Abiri, 2015;Salehi and Noori, 2014;Rezaei, Noori and Hosseini, 2018) high/low impedance sections (branch-line structures), in (Sun, et al, 2005) discontinuous microstrip lines, in (Lai and Ma, 2013) interdigital series structures (rat-race structure), in (Tian, et al, 2019) composite planar transmission lines, and in (Maheswari and Jayanthy, 2022) a simple hollow rectangle is utilized to obtain the microstrip couplers. To miniaturize, the simple conventional rectangle of the branch-line coupler is loaded by T-shape inner stubs in (Lalbakhsh, et al, 2021).…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

A Comprehensive Review on Microstrip Couplers

Yahya²,

Noori³

2023

ARO

In this work, several types of microstrip couplers are investigated in terms of structure, performance and design methods. These planar 4-ports passive devices transmit a signal through two different channels. Designers' competition has always been in miniaturizing and improving performance of couplers. Some couplers have been offered with a novel structure, which is a special feature. A high-performance coupler should have high isolation and low losses at both channels. The channels are usually overlapped so that the common port return loss in these channels should be low. Among the couplers, those with balanced amplitude and phase are more popular. The popular mathematical analysis methods are even/odd mode analysis, extracting the information from the ABCD matrix and analyzing the equivalent LC circuit of a simple resonator. According to the phase shift value, couplers are classified as 90º and correct multiples of 90º, where a microstrip 0º coupler can be used as a power divider. Some couplers have filtering and harmonic elimination features that are superior to other couplers. However, few designers paid attention to suppressing the harmonics. If the operating frequency is set in according to the type of application, the coupler becomes particularly valuable.ABCD Matrix

A high‐performance microstrip bandpass filtering coupler with low‐loss and compact size

Micro & Optical Tech Letters

Yahya

Noori

2023

In this letter, novel spiral‐coupled transmission lines are used to obtain a high‐performance microstrip coupler. The advantages of the proposed microstrip coupler are novel structure, filtering frequency response, suppressed harmonics up to second harmonics, transmission poles, low losses, compact size, and good phase balance. The proposed structure is novel and different from the previous coupler designs such as rate‐races, rings, and branch‐lines types. It is presented for the first time in this work with a very small size and good performance. The size of this coupler is only 82.6 mm2 (0.004 λg2). The common port return loss is 33 dB and the insertion losses at port 2 and port 3 are 2.2 and 2.7 dB, respectively. To prove the accuracy of the design method and simulation results, the proposed coupler is fabricated and measured where the measurement results confirm the simulation results and the proposed design method.