This work provides an in-depth study on a linear antenna array that consists of 32 elements of CRLH unit cells, and the main radiating beam can be controlled by changing the capacitance of the varicap diode that was designed and simulated with Advanced Design System (ADS 2014) software. ADS software was selected because of its flexibility in accommodating complex design equations. Results show that the main beam can be steered up to 50 degrees from the direction of maximum radiation by changing the capacitances. The main beam gain of the antenna array at boresight of 12 dB has been achieved with an impedance bandwidth of 3 GHz at 10 dB gain threshold. The antenna array performance was analysed in the mmWave frequency range at centre frequency of 28 GHz making it suitable for the upcoming 5G applications. The mmWave path losses were handled by increasing the gain of the antenna array and steering the main lobe over 50 degrees to balance the gain coverage trade-off. The direction of the main beam is controlled by changing the varicap capacitance accordingly.
2. Dehos, C., J. L. Gonzalez, A. De Domenico, D. Ktenas, and L. Dussopt, "Millimeter-wave access and backhauling: The solution to the exponential data traffic increase in 5G mobile communications systems?," IEEE Communications Magazine, 88-94, September 2014.
3. Jeong, C., J. Park, and H. Yu, "Random access in millimeter-wave beamforming cellular networks: Issues and approaches," IEEE Communications Magazine, 180-185, January 2015.
4. Elkhouly, M., C.-S. Choi, S. Glisic, C. Scheytt, and F. Ellinger, "Millimeter-wave beamforming circuits in SIGe BICMOS," 2010 IEEE Bipolar/BiCMOS Circuits and Technology Meeting (BCTM), 129-132, Austin-Texas, USA, October 4–6, 2010.
5. Hur, S., T. Kim, D. J. Love, J. V. Krogmeier, T. A. Thomas, and A. Ghosh, "Millimeter wave beamforming for wireless backhaul and access in small cell networks," IEEE Transactions on Communications, Vol. 61, No. 10, 4391-4403, October 2013.
6. Qiao, J., X. Shen, J. W. Mark, Q. Shen, Y. He, and L. Lei, "Enabling device-to-device communications in millimeter-wave 5G celluar networks," IEEE Communications Magazine, 209-214, January 2015.
7. Abdulla, M. A., "A dual mode CRLH TL metamaterial antenna," Antennas & Propagation Society International Symposium, 793-794, IEEE, June 2014.
8. Song, J., S. G. Larew, D. J. Love, T. A. Thomas, and A. Ghosh, "Millimeter wave beamforming for multiuser dual-polarized MIMO systems," 2013 IEEE Global Conference on Signal and Information Processing, 719-722, December 3–5, 2013.
9. Kim, J. and A. F. Molisch, "Fast millimeter-wave beam training with receiver beamforming," Journal of Communications and Networks, Vol. 16, No. 5, 512-522, October 2014.
10. Ross, R. F. G. and M. J. Howes, "Simple formulas for microstrip lines," Article Electronics Letters, Vol. 12, No. 16, 410, August 1976.
11. Wu, P.-C., L. Chen, and Y.-L. Luo, "Miniaturized wideband filtering antenna by employing CRLH-TL and simplified feeding structure," Electronics Letters, Vol. 51, No. 7, 548-550, April 2015.
12. Djerafi, T., B. Youzkatli-el-Khatib, K. Wu, and S.-O. Tatu, "Substrate integrated waveguide antenna subarray for broadband circularly polarised radiation," IET Microw. Antennas Propag., Vol. 8, No. 14, 1179-1185, 2014.
13. Jung, E.-Y., J. W. Lee, T. K. Lee, and W.-K. Lee, "SIW-based array antennas with sequential feeding for X-band satellite communication," IEEE Trans. Antennas Propag., Vol. 60, No. 8, 3632-3639, 2012.
14. Li, Y., Z. N. Chen, X. Qing, Z. Zhang, J. Xu, and Z. Feng, "Axial ratio bandwidth enhancement of 60-GHz substrate integrated waveguide-fed circularly polarized LTCC antenna array," IEEE Trans. Antennas Propag., Vol. 60, No. 10, 4619-4626, 2012.