A dual‐band balanced amplifier using three‐layer technology

Abstract

In this work, we demonstrate a low power and low NF W-band LNA using standard 90-nm CMOS technology. The LNA comprises three CS stages. The LNA consumes 21.1 mW, achieving group delay variation smaller than 66.5 ps for frequencies 70-90 GHz, and high and flat S 21 of 13.1 6 1.5 dB for frequencies 72-84 GHz. In addition, the LNA achieves minimum NF of 6.2 dB at 78 GHz and NF of 6.8 6 0.6 dB for frequencies 75-82 GHz, one of the best NF results ever reported for a W-band CMOS or SiGe BiCMOS LNA. The impressive results from this work signify the high potential of the proposed LNA architecture in W-band transceiver applications.ABSTRACT: A multilayer technology is applied to design a dual-band branch-line coupler for the dual-band balanced amplifier. The proposed coupler is designed based on a three-layer printed circuit board. The dual-band operation is achieved by four additional shunt stubs at the middle layer, while the upper layer is the core and active circuits layer and the bottom is ground layer. The proposed coupler with equal power division is designed at two frequencies of 1.1 and 1.9 GHz. Besides, a balanced amplifier is also designed which achieves gain of 11.6 and 10.1 dB at 1.1 and 1.9 GHz, respectively.

A Novel Dual-Band Balanced Power Amplifier Using Branch-Line Couplers With Four Arbitrary Terminated Resistances

“…Balanced power amplifier is a popular topology of the amplifiers, which consists of two identical single-stage power amplifiers, input power splitter and output power combiner [4][5][6]. The benefits of balanced amplifier configuration were first recognized in [7], and the advantages of the balanced power amplifier can be summarized as follows: (1) Any mismatch reflections from the amplifiers pass back through the couplers and appear in anti-phase and therefore cancel at the RF input (or output) port [7].…”