In this paper, we present a planar array for near-field shaped focusing. A near-field synthesis method for forming a special pattern on the focal plane is investigated. The phase and amplitude of the array are adjusted by digital phase shifters and attenuators. Prototypes are fabricated and measured to verify the effectiveness of this method. Near-field shaped focusing performances with square and triangular patterns are realized respectively. The experimental results show that the method can focus the electric field to a designated area clearly. Our work can provide a reference for applications such as microwave hyperthermia and wireless power transfer.
2. Bogosanovic, M. and A. Williamson, "Microstrip antenna array with a beam focused in the near-field zone for application in noncontact microwave industrial inspection," IEEE Trans. Instrum. Meas., Vol. 56, No. 6, 2186-2195, Dec. 2007.
doi:10.1109/TIM.2007.907954
3. Jouade, A., L. Ferro-Famil, S. Meric, O. Lafond, and L. Coq, "High resolution radar focusing using spectral estimation methods in wide-band and near-field configurations: Application to millimeter-wave near-range imaging," Progress In Electromagnetics Research B, Vol. 79, 45-64, 2017.
doi:10.2528/PIERB17082402
4. Shavit, R., T. Wells, and A. Cohen, "Forward-scattering analysis in a focused-beam system," IEEE Trans. Antennas Propag., Vol. 46, No. 4, 563-569, Apr. 1998.
doi:10.1109/8.664122
5. Karimkashi, S. and A. Kishk, "Focusing properties of Fresnel zone plate lens antennas in the near-field region," IEEE Trans. Antennas Propag., Vol. 59, No. 5, 1481-1487, May 2011.
doi:10.1109/TAP.2011.2123069
6. Wu, Y., Y. Cheng, and Z. Huang, "Ka-band near-field-focused 2-D steering antenna array with a focused rotman lens," IEEE Trans. Antennas Propag., Vol. 66, No. 10, 5204-5213, Oct. 2018.
doi:10.1109/TAP.2018.2856113
7. Hao, H., S. Zheng, Y. Tang, and X. Ran, "Design of electromagnetic wave multi-type focusing based on 1-bit metasurface," Progress In Electromagnetics Research M, Vol. 105, 79-88, 2021.
doi:10.2528/PIERM21080505
8. Yu, S., N. Kou, Z. Ding, and Z. Zhang, "Design of dual-polarized reflectarray for near-field shaped focusing," IEEE Antennas Wirel. Propag. Lett., Vol. 20, No. 5, 803-807, May 2021.
doi:10.1109/LAWP.2021.3063848
9. Karimkashi, S. and A. Kishk, "Focused microstrip array antenna using a Dolph-Chebyshev near-field design," IEEE Trans. Antennas Propag., Vol. 57, No. 12, 3813-3820, Dec. 2009.
doi:10.1109/TAP.2009.2033435
10. Li, P., S. Qu, S. Yang, Y. Liu, and Q. Xue, "Microstrip array antenna with 2-D steerable focus in near-field region," IEEE Trans. Antennas Propag., Vol. 65, No. 9, 4607-4617, Sept. 2017.
doi:10.1109/TAP.2017.2726579
11. Siragusa, R., P. Lemaitre-Auger, and S. Tedjini, "Tunable near-field focused circular phase-array antenna for 5.8-GHz RFID applications," IEEE Antennas Wirel. Propag. Lett., Vol. 10, 33-36, 2011.
doi:10.1109/LAWP.2011.2108632
12. Tofigh, F., J. Nourinia, M. Azarmanesh, and K. Khazaei, "Near-field focused array microstrip planar antenna for medical applications," IEEE Antennas Wirel. Propag. Lett., Vol. 13, 951-954, 2014.
doi:10.1109/LAWP.2014.2322111
13. Wu, Y., Y. Cheng, S. Yao, and Y. Fan, "Millimeter-wave near-field-focused full 2-D frequency scanning antenna array with height-modulated-ridge waveguide," IEEE Trans. Antennas Propag., Vol. 69, No. 5, 2595-2604, May 2021.
doi:10.1109/TAP.2020.3044080
14. Li, Y., S. Yu, N. Kou, Z. Ding, and Z. Zhang, "Cylindrical conformal array antenna for near field focusing," Int. J. RF Microw. Comput.-Aided Eng., Vol. 32, No. 6, e23135, 2022.
doi:10.1002/mmce.23135
Submit
