A new design idea of MIMO beamforming antenna array for compact and thin handheld devices is investigated, where the beamforming function is used for transmitting and the MIMO function for receiving. The new design idea is illustrated by an antenna array consisting of eight printed planar inverted-F elements operating at GSM1900 (1880-1920 MHz) and LTE2300 (2300-2400 MHz). The 8-element antenna array is printed on an FR4 substrate of dimensions 136 mm × 68.8 mm × 1 mm. By using the radiation pattern diversity, good isolations, envelope correlation coefficients and mean effective gains are achieved for MIMO receiving. To realize the beamforming function when the antenna is used for transmitting, an optimal feeding mechanism is introduced by the method of maximum power transmission efficiency, which is then implemented by a continuously adjustable feeding circuit board. With the optimized feeding mechanism, the gain of the antenna array in the desired direction can be significantly enhanced. The effects of the human body on the performance of antenna array are also examined, and the results indicate that the proposed design still exhibits good MIMO and beamforming performances in a practical scenario.
"Design of MIMO Beamforming Antenna Array for Mobile Handsets," Progress In Electromagnetics Research C,
Vol. 94, 13-28, 2019. doi:10.2528/PIERC19030807
1. Dahlman, E., S. Parkvall, and J. Skold, 4G: LTE/LTE-advanced for Mobile Broadband, Academic Press, 2013.
2. Shajaiah, H., A. Abdel-Hadi, and C. Clancy, "Spectrum sharing between public safety and commercial users in 4G-LTE," Int. Conf. Computing Networking Commun. (ICNC), 674-679, Honolulu, HI, USA, Feb. 2014.
3. Rappaport, T. S., et al., "Millimeter wave mobile communications for 5G cellular: It will work!," IEEE Access, Vol. 1, 335-349, May 2013. doi:10.1109/ACCESS.2013.2260813
4. Dehos, C., et al., "Millimeter-wave access and backhauling: The solution to the exponential data tra±c increase in 5G mobile communications systems?," IEEE Commun. Mag., Vol. 52, No. 9, 88-95, 2014. doi:10.1109/MCOM.2014.6894457
5. Silvia, S., H. Tabassum, and E. Hossain, "Multi-tier Drone architecture for 5G/B5G cellular networks: Challenges, trends, and prospects," IEEE Commun. Mag., Vol. 56, No. 3, 96-103, Mar. 2018. doi:10.1109/MCOM.2018.1700666
6. Wi, H., B. Kim, W. Jung, and B. Lee, "Multiband handset antenna analysis including LTE band MIMO service," Progress In Electromagnetics Research, Vol. 138, 661-673, 2013. doi:10.2528/PIER13022408
7. Ilvonen, J., R. Valkonen, J. Holopainen, and V. Viikari, "Multiband frequency reconfigurable 4G handset antenna with MIMO capability," Progress In Electromagnetics Research, Vol. 148, 233-243, 2014. doi:10.2528/PIER14062703
8. Hong, W., K. H. Baek, and S. Ko, "Millimeter-wave 5G antennas for smartphones: Overview and experimental demonstration," IEEE Trans. Antennas Propag., Vol. 65, No. 12, 6250-6261, Aug. 2017. doi:10.1109/TAP.2017.2740963
9. Ban, Y. L., et al., "Small-size printed coupled-fed antenna for eight-band LTE/GSM/UMTS wireless wide area network operation in an internal mobile handset," IET Microw. Antennas Propag., Vol. 7, No. 6, 399-407, Jun. 2013. doi:10.1049/iet-map.2012.0390
10. Ahmed, F., Y. Feng, and R. Li, "Dual wide-band four-unit MIMO antenna system for 4G/LTE and WLAN mobile phone applications," 2013 Loughborough Antennas Propag. Conf. (LAPC), 202-207, Loughborough, UK, Nov. 2013.
11. Khan, R., A. Abdullah Al-Hadi, and P. J. Soh, "Efifciency of millimeter wave mobile terminal antennas with the inlfuence of users," Progress In Electromagnetics Research, Vol. 161, 113-123, 2018. doi:10.2528/PIER18012409
12. Li, M. Y., et al., "Eight-port orthogonally dual-polarized antenna array for 5G smartphone applications," IEEE Trans. Antennas Propag., Vol. 64, No. 9, 3820-3830, Sep. 2016. doi:10.1109/TAP.2016.2583501
13. Chen, Z. L., et al., "A study of MIMO antenna system for high order MIMO device," Int. J. Antennas Propag., 2016. doi:10.1109/TAP.2016.2583501
14. Hussain, R., A. T. Alreshaid, S. K. Podilchak, and M. S. Sharawi, "Compact 4G MIMO antenna integrated with a 5G array for current and future mobile handsets," IET Microw. Antennas Propag., Vol. 11, No. 2, 27-1279, Jan. 2017. doi:10.1049/iet-map.2016.0738
15. Zhang, W. J., Z. B.Weng, and L.Wang, "Design of a dual-band MIMO antenna for 5G smartphone application," 2018 Int. Workshop Antenna Technol. (iWAT), Nanjing, China, Jun. 2018.
16. Li, Y., Y. Luo, and G. L. Yang, "12-port 5G massive MIMO antenna array in sub-6 GHz mobile handset for LTE bands 42/43/46 applications," IEEE Access, Vol. 6, 344-354, Oct. 2018.
17. Dinger, R. J., "A planar version of a 4.0 GHz reactively steered adaptive array," IEEE Trans. Antennas Propag., Vol. 34, No. 3, 427-431, Mar. 1986. doi:10.1109/TAP.1986.1143826
18. Tsoulos, G. V., "Smart antennas for mobile communication systems: Benefits and challenges," Electron. Commun. Engineering J., Vol. 11, No. 2, 84-94, 1999. doi:10.1049/ecej:19990204
19. Dietrich, C. B., et al., "Smart antennas in wireless communications: Base-station diversity and handset beamforming," IEEE Antennas Propag. Mag., Vol. 42, No. 5, 142-151, 2000. doi:10.1109/74.883513
20. Tong, H. P. and G. Wen, "Optimal design of smart antenna systemsfor handheld devices," IET Microw. Antennas Propag., Vol. 10, No. 6, 617-623, Jun. 2016. doi:10.1049/iet-map.2015.0339
21. Liang, G., W. Gong, H. Liu, and J. Yu, "Development of 61-channel digital beamforming (DBF) transmitter array for mobile satellite communication," Progress In Electromagnetics Research, Vol. 97, 177-195, 2009. doi:10.2528/PIER09082303
22. Wan, W., G. Wen, and S. Gao, "Optimum design of low-cost dual-mode beam-steerable arrays for customer-premises equipment applications," IEEE Access, Vol. 6, 16092-16098, Mar. 2018. doi:10.1109/ACCESS.2018.2813299
23. Yu, B., K. Yang, and G. L. Yang, "A novel 28 GHz beam steering array for 5G mobile device with metallic casing application," IEEE Trans. Antennas Propag., Vol. 66, No. 1, 462-466, Jan. 2018. doi:10.1109/TAP.2017.2772084
24. Yang, B. Q., et al., "Digital beamforming-based massive MIMO transceiver for 5G millimeter-wave communications," IEEE Trans. Microw. Theory Techn., Vol. 66, No. 7, 3403-3418, May 2018. doi:10.1109/TMTT.2018.2829702
25. Liu, X., et al., "Beam-oriented digital predistortion for 5G massive MIMO hybrid beamforming transmitters," IEEE Trans. Microw. Theory Techn., Vol. 66, No. 7, 3419-3432, May 2018. doi:10.1109/TMTT.2018.2830772
26. Jo, O., et al., "Exploitation of dual-polarization diversity for 5G millimeter-wave MIMO beamforming systems," IEEE Trans. Antennas Propag., Vol. 65, No. 12, 6646-6655, Dec. 2017. doi:10.1109/TAP.2017.2761979
27. Wen, G., Foundations of Applied Electrodynamics, 273-275, Wiley, New York, NY, USA, 2010.
28. Wen, G., Foundations for Radio Frequency Engineering, 410-420, World Scientific, 2015. doi:10.1142/9040
30. Blanch, S., J. Romeu, and I. Corbella, "Exact representation of antenna system diversity performance from input parameter description," Electron. Lett., Vol. 39, No. 9, 705-707, May 2003. doi:10.1049/el:20030495
31. Mikki, S. M. and Y. M. M. Antar, "On cross correlation in antenna arrays with applications to spatial diversity and MIMO systems," IEEE Trans. Antennas Propag., Vol. 63, No. 4, 1798-1810, Apr. 2015. doi:10.1109/TAP.2015.2398113
32. Sharawi, M. S., A. T. Hassan, and M. U. Khan, "Correlation co-efficient calculations for MIMO antenna systems: A comparative study," Int. J. Microw. Wireless Technol., 1-14, 2017.
33. Taga, T., "Analysis for mean effective gain for mobile in land mobile radio environments," IEEE Trans. Vehicular Technol., Vol. 39, No. 2, 117-131, May 1990. doi:10.1109/25.54228
34. Karaboikis, M. P., et al., "Integrating compact printed antennas onto small diversity/MIMO terminals," IEEE Trans. Antennas Propag., Vol. 56, No. 7, 2067-2078, 2008. doi:10.1109/TAP.2008.924677
35. Ko, S. C. and R. D. Murch, "Compact integrated diversity antenna for wireless communications," IEEE Trans. Antennas Propag., Vol. 47, No. 6, 954-960, Jun. 2001. doi:10.1109/8.931154
36. Shan, L. and G. Wen, "Optimal design of focused antenna arrays," IEEE Trans. Antennas Propag., Vol. 62, No. 11, 5565-5571, Nov. 2014. doi:10.1109/TAP.2014.2357421
37. Cai, X., G. Wen, and H. C. Sun, "A printed dipole array with high gain and endfire radiation," IEEE Antennas Wireless Propag. Lett., Vol. 16, 1512-1515, 2017. doi:10.1109/LAWP.2016.2647319
38. Cai, X. and G. Wen, "An optimization method for the synthesis of flat-top radiation patterns in the near-field and far-field regions," IEEE Trans. Antennas Propag., No. 2, Feb. 2019.
39. Gu, X. Z. and G. Wen, "Design of a near-field RFID antenna array in metal cabinet environment," IEEE Antennas Wireless Propag. Lett., Vol. 18, 79-83, 2019. doi:10.1109/LAWP.2018.2880965