Dual-band impedance transformation networks for integrated power amplifiers

Abstract

This paper shows that the two most common impedance transformation networks for power amplifiers (PAs) can be designed to achieve optimum transformation at two frequencies. Hence, a larger bandwidth for the required impedance transformation ratio is achieved. A design procedure is proposed, which takes imperfections like losses into account. Furthermore, an analysis method is presented to estimate the maximum uncompressed output power of a PA with respect to frequency. Based on these results, a fully integrated PA with a dual-band impedance transformation network is designed and its functionality is proven by large signal measurement results. The amplifier covers the frequency band from 450 MHz to 1.2 GHz (3 dB bandwidth of the output power and efficiency), corresponding to a relative bandwidth of more than 100%. It delivers 23.7 dBm output power in the 1 dB compression point, having a power-added efficiency of 33%.

A millimeter-wave fundamental and subharmonic hybrid CMOS mixer for dual-band applications

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Millimeter-wave dual-mode and dual-band switchable Gilbert up-conversion mixer in 65-nm CMOS process

“…Traditional design strategies have adopted separate single-band radio-frequency (RF) front-ends in parallel for multi-band and multi-standard operations, which increase the power consumption and chip size. To alleviate this problem, the RF building blocks which can be shared among multiple frequency bands are highly required [1–3].…”

2.4‐GHz CMOS linear power amplifier for IEEE 802.11N WLAN applications

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