Erratum for: Design of double ring hybrid using intentionally mismatching method

Abstract

realize broadband absorber. However, when we study the surface current distribution, it seems that the physical origin is similar to polarization conversion that we have researched [2]- [5]. What's more, similar structure has been designed to realize broad band polarization conversion at Terahertz [6].Our conclusion is that it should be cross-polarization conversion rather than absorption. The structure in [1] is resimulated by a commercial software CST MICROWAVE STUDIO and the simulation results confirm with our conclusion. The resimulated reflectance with different polarization are illustrated in Figure 1. The copolarized reflection is low; however, the cross-polarized reflection is very strong.According to the polarization conversion effect of this structure, it can be concluded that |S 11 | 2 5 |S co | 2 1 |S cross | 2 [7], where |S 11 | is the total reflection, |S co | and |S cross | are co-and cross-polarized reflection coefficients respectively. In Figure 2, the |S 11 | 2 is shown and its value is over 0.84 in the simulation frequency range.The absorption is expressed as A 5 1 2 |S 11 | 2 2 |S 21 | 2 , where |S 21 | is the transmittance. The correct absorption is depicted in Figure 3. As is shown, the structure do not have strong microwave absorption effect and should not be considered as an absorber. For other incident angle, the conclusion is similar.The surface currents shown in Figures 6 and 7 from [1] are similar to the previous work which performance as a cross polarization convertor [2]. The explanation in section 4 of [1] should be the mechanism of the polarization conversion rather than the mechanism of absorption.Finally, we hope our work may reduce the misunderstanding of [1]. In the above-mentioned article, which appeared in Microwave and Optical Technology Letters, Volume 58#3, DOI 29633, there was an error in the title. The title as published was incomplete. The corrected, complete title is shown below: DESIGN OF DOUBLE RING HYBRID USING INTEN-TIONALLY MISMATCHING METHODWe apologize for this error and regret any confusion that was caused.

A new type of planar 180° hybrid using intentional impedance mismatch for improved bandwidth and arbitrary power division ratio

“…The achieved parameters of the proposed structure in comparison with the results published references are summarized in Table , in terms of power‐division ratios (3 dB). Based on bandwidth within ±10° of in‐phase or out‐of phase, the bandwidth of is >70% in 3 dB power division ratio, but it is difficult to cascade with other devices.…”

“…Based on bandwidth within ±10° of in‐phase or out‐of phase, the bandwidth of is >70% in 3 dB power division ratio, but it is difficult to cascade with other devices. On the other hand, cascadable connections to other devices have a narrow bandwidth.…”

“…However, the ring hybrids of these research papers are difficult to implement in a planar connection because of the port direction when connecting with other devices. Therefore, 180 hybrids with improved port directions and doublering hybrid with intentionally mismatching method have been proposed, but they are not completely planar type and have limited bandwidth …”

“…Moreover, it is difficult to apply to planar wireless systems due to output port in different directions. Thus, some research has been conducted on improving the disadvantages . First, to improve the narrow bandwidth, the 3λ/4 line section of the conventional ring hybrid is replaced with the λ/4 coupled section, which is realized on stripline.…”

“…Thus, some research has been conducted on improving the disadvantages. [1][2][3][4][5][6][7] First, to improve the narrow bandwidth, the 3λ/4 line section of the conventional ring hybrid is replaced with the λ/4 coupled section, 1 which is realized on stripline. Ring hybrids in the coplanar waveguide slotline configuration, also, have been proposed.…”