A novel dual-band balanced power amplifier (DBPA) using a pair of branch-line couplers with four arbitrary terminated resistances is designed in this paper. The DBPA operating at 2.02 GHz and 2.6 GHz consists of two identical single-stage class-AB PAs connected in parallel and two branch-line couplers for power division and combination. Due to the usage of branch-line couplers with four arbitrary terminated resistances, the load/source-pull impedance obtained by ADS (Advanced Design System) can be matched to an arbitrary real impedance which decreases the complexity of dual-band matching network of the DBPA. To demonstrate the proposed design, a prototype based on CREE's GaN HEMT CGH40010F is fabricated and measured. The simulated results exhibit 67.9% and 73.6% power-added efficiency (PAE) values with output power of 44.1 and 43.4 dBm at 2.02 GHz and 2.6 GHz, respectively.
2. Gao, L., X. Zhang, S. Chen, and Q. Xue, "Compact power amplifier with band-pass response and high efficiency," IEEE Microwave and Wireless Components Letters, Vol. 24, No. 10, 707-709, Oct. 2014.
3. Kizilbey, O. and O. Palamutcuogullari, "Design of 3.3-3.7 GHz GaN HEMT balanced class E power amplifier," Proceedings of the 7th International Conference Onelectrical and Electronics Engineering, Dec. 2011.
4. Dettmann, I., L. Wu, and M. Berroth, "Comparison of a single-ended class AB, a balance and a doherty power amplifier," Proceedings of Asia-Pacific Microwave Conference, Dec. 2005.
5. Eisele, K., R. Engelbrecht, and K. Kurokawa, "Balanced transistor amplifiers for precise wideband microwave applications," Proceedings of Solid State Circuits Conference, Feb. 1965.
6. Hou, Z. and L. Chiu, "A dual-band balanced amplifier using three-layer technology," Microwaveand Optical Technology Letters, Vol. 56, No. 7, 1680-1683, Jul. 2014.
7. Cripps, S. C., RF Power Amplifier Wireless Communication, 380-387, Artech House, 1999.
8. Wu, L., U. Basaran, I. Dettmann, M. Berroth, T. Bitzer, and A. Pascht, "A broadband high efficiency class-AB LDMOS balanced power amplifier," Proceeding of European Microwave Conference, Oct. 2005.
9. Wu, Y., S. Zheng, S. Leung, Y. Liu, and Q. Xue, "An analytical design method for a novel dual-band unequal coupler with four arbitrary terminated resistances," IEEE Transactionon Industrial Electronics, Vol. 61, No. 10, 5509-5516, Oct. 2014.
10. Liu, X., Y. Liu, S. Li, F. Wu, and Y. Wu, "A three-section dual-band transformer for frequency-dependent complex load impedance," IEEE Microwaveand Wireless Components Letters, Vol. 19, No. 10, 611-613, Oct. 2009.
11. Monzon, C., "A small dual-frequency transformerin two sections," IEEE Transaction. Microwave Theory and Techniques, Vol. 51, No. 4, 1157-1161, Apr. 2003.
12. Wu, Y., Y. Liu, S. Li, C. Yu, and X. Liu, "A generalized dual-frequency transformer for two arbitrary complex frequency-dependent impedances," IEEE Microwave and Wireless Components Letters, Vol. 19, No. 12, 792-794, Dec. 2009.