TY - JOUR
T1 - Compact Microstrip Antennas with Enhanced Bandwidth for the Implanted and External Subsystems of a Wireless Retinal Prosthesis
AU - Bahrami, Siroos
AU - Moloudian, Gholamhosein
AU - Mirirostami, Seyyedreza
AU - Björninen, Toni
N1 - Funding Information:
Manuscript received March 18, 2020; revised August 17, 2020; accepted August 31, 2020. Date of publication September 24, 2020; date of current version May 5, 2021. The work of Toni Björninen was supported by the Academy of Finland under Grant 294616. (Corresponding author: Toni Björninen.) Siroos Bahrami and Gholamhosein Moloudian are with the Electrical Engineering Department, Salman Farsi University of Kazerun, Kazerun 73544-73196, Iran.
Publisher Copyright:
© 1963-2012 IEEE.
PY - 2020/9/24
Y1 - 2020/9/24
N2 - In this paper, two pairs of compact microstrip antennas were introduced for a dual-unit retinal prosthesis operating at two frequencies of 1.45 GHz and 2.45 GHz. For 2.45 GHz frequency band, a triangular microstrip antenna with shorting pin and 7 × 6.93 × 0.63 mm dimensions is explored to enhance intraocular element bandwidth. Also, a modified rectangular patch (26 × 24 × 1.43 mm) with parasitic radiators is employed for the extraocular element. In 1.45 GHz frequency band, another triangular microstrip intraocular element (6.25 × 6 × 0.63 mm) is proposed by etching a series of slots which results in lower resonance frequency. For the extraocular element at 1.45 GHz, a Planar Inverted-F antenna (PIFA) (28 × 24 × 1.43 mm) with parasitic radiators is introduced. The effectiveness of intraocular and extraocular antennas was evaluated through simulation and further examined by fabricating to characterize the performance in a wireless system inside eye phantom. Specific absorption rate (SAR) analysis of the proposed antennas, results of the simulation and experimental coupling measurements are presented. Compared to others work in this problem, with this proposed structure, we could enhance the impedance bandwidth up to 36% without compromising the coupling which is advantageous for high-resolution retinal prosthesis.
AB - In this paper, two pairs of compact microstrip antennas were introduced for a dual-unit retinal prosthesis operating at two frequencies of 1.45 GHz and 2.45 GHz. For 2.45 GHz frequency band, a triangular microstrip antenna with shorting pin and 7 × 6.93 × 0.63 mm dimensions is explored to enhance intraocular element bandwidth. Also, a modified rectangular patch (26 × 24 × 1.43 mm) with parasitic radiators is employed for the extraocular element. In 1.45 GHz frequency band, another triangular microstrip intraocular element (6.25 × 6 × 0.63 mm) is proposed by etching a series of slots which results in lower resonance frequency. For the extraocular element at 1.45 GHz, a Planar Inverted-F antenna (PIFA) (28 × 24 × 1.43 mm) with parasitic radiators is introduced. The effectiveness of intraocular and extraocular antennas was evaluated through simulation and further examined by fabricating to characterize the performance in a wireless system inside eye phantom. Specific absorption rate (SAR) analysis of the proposed antennas, results of the simulation and experimental coupling measurements are presented. Compared to others work in this problem, with this proposed structure, we could enhance the impedance bandwidth up to 36% without compromising the coupling which is advantageous for high-resolution retinal prosthesis.
U2 - 10.1109/TAP.2020.3025245
DO - 10.1109/TAP.2020.3025245
M3 - Article
SN - 0018-926X
VL - 69
SP - 2969
EP - 2974
JO - IEEE Transactions on Antennas and Propagation
JF - IEEE Transactions on Antennas and Propagation
IS - 5
ER -