Design a GaN HEMT-Based Broadband High-Efficiency Rectifier Using a Wideband Phase Shift Structure
Zhiwei Zhang, Chao Gu, Zhiqun Cheng, Xuefei Xuan
Abstract
This letter presents a broadband high-efficiency rectifier based on a GaN transistor. A wideband phase shift structure consisting of parallel coupled lines and T-shaped networks is utilized to realize a constant phase shift over a wide frequency band. Besides, the continuous class- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{F}^{-1}$ </tex-math></inline-formula> operation mode theory is employed to obtain high efficiency across a wide frequency band. The combination of the phase shift network and the continuous class- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{F}^{-1}$ </tex-math></inline-formula> operation mode leads to a wideband high-efficiency RF-dc rectifier operation. Moreover, shunt transmission lines in T-shaped networks are replaced by existing bias lines, which significantly reduce the size of the circuit. For validation, a broadband high-efficiency RF-dc rectifier operating in 2.0–3.0 GHz is designed and fabricated using a CGH40010F GaN high electron mobility transistor (HEMT). Measurements illustrate that the implemented rectifier can realize an efficiency of over 70% across the entire operating band when an input power of 40 dBm is applied and the dc load is <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$65~\Omega $ </tex-math></inline-formula> . Also, the size of the resultant circuit is only <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$2.0\times1.8$ </tex-math></inline-formula> cm.