Open AccessCompact wearable 5‐GHz flexible filter
Author(s) -
Zhao Mengjuan,
Zhang Yong
Publication year - 2017
Publication title -
electronics letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.375
H-Index - 146
eISSN - 1350-911X
pISSN - 0013-5194
DOI - 10.1049/el.2017.0625
Subject(s) - return loss , insertion loss , stub (electronics) , materials science , filter (signal processing) , acoustics , transmission loss , electronic engineering , optoelectronics , electrical engineering , computer science , telecommunications , engineering , physics , antenna (radio)
A compact flexible filter based on 0° feed structure with ultrathin liquid crystal polymer substrate is proposed firstly. An open‐ended stub is introduced to improve the out‐band rejection. The presented flexible filter with dimension of 6.48 × 9.89 × 0.086 mm 3 is operating at WLAN of 5.15–5.875 GHz, which will alleviate the channel congestion of 2.4 GHz. In the case of flat, the measured minimum insertion loss is 1.9 dB at 5.61 GHz and the return loss is better than 16.45 dB. The bending behaviour of the compact flexible filter is also analysed. Compared with the flat case, the return loss is optimised by 0.45 dB, the maximum deterioration of insertion loss is 0.13 dB in case of R = 10 mm, and the transmission zeros position are invariant. Good agreement is obtained between the flat and the bending situation, which shows that the presented flexible filter is promising for the wearable applications.