A broadband and excellent flatness power amplifier with novel‐designed band‐pass filter based on composite right/left‐handed unit cell

Abstract

In this paper, a broadband and excellent flatness power amplifier (PA) with a novel‐designed band‐pass filter based on composite right/left‐handed (CRLH) unit cell structure is proposed. On studying the structure of CRLH unit cell, a way to enhance PA bandwidth, gain flatness, and power‐added efficiency (PAE) flatness is explored. The novel‐designed CRLH unit cell structure is studied and applied in PA design. The measurements show that the PA has an output power of greater than 40 dBm, a gain flatness of 0.5 dB, and a PAE flatness of 4.4% within 1.7‐3.1 GHz bandwidth.

A concurrent 2.6/3.5GHz dual-band Doherty power amplifier with matching network based on composite right/left-handed unit cell

“…Finally, the π-type microstrip network is added to achieve the optimal impedance matching of the OPBO together with the previous CRLH-TL. According to [31], the CRLH-TL unit cell composed of lumped elements can be converted to the microstrip to improve the performance of the circuit. The final output matching network structure is shown in Fig.…”

Developing a broadband band‐pass filtering power amplifier with enhanced performance

“…Recently, researchers have proposed some solutions to these problems. In Luo et al, 5 the author integrated the composite right/left‐handed unit cell structure into the design of output matching to achieve filtering response, but this only resulted in two transmission zeros and limited filtering performance. In Meng et al, 6 a method for implementing continuous J‐class PAs using bandpass and low‐pass matching networks is introduced; by utilizing λ/4 open stub, the design achieved a passband response, while the output is a traditional low‐pass matching structure.…”

“…In Li et al, 7 Qi and Xiao, 8 Chen et al, 11 the design methods could not realize broadband performance. In Luo et al 5 and Qi and Xiao, 8 the suppression of low‐frequency bands is insufficient, while Feng et al 10 is characterized by complex manufacturing and easy introducing parasitic effects.…”

“…[11][12][13] However, a close observation of these filtering amplifiers reveals some shortcomings or gaps. For example, in Luo et al, 5 Qi and Xiao, 8 Xu et al, 12 the design process involves designing filters and amplifiers separately to the same agreed impedances and then cascading them for optimization, which is essentially still a traditional solution. In Li et al, 7 Qi and Xiao, 8 Chen et al, 11 the design methods could not realize broadband performance.…”