Highly efficient broadband class‐J power amplifier using modified multisection quarter‐wave lines and short‐circuited stubs

Abstract

This study presents a broadband and high‐efficiency Class‐J power amplifier (PA)‐based on a modified multisection quarter‐wave lines and short‐circuited stubs matching network (MN). It is noted that the modified structure, with good design convenience and great frequency selectivity, especially in the roll‐off region between the highest frequency of the desired band (fH) and second harmonic of the lowest frequency of the band (2fL), is for the first time employed to design PAs with more optimal performance and greater bandwidths (BWs). A step‐by‐step design procedure of the proposed structure is presented. Experimental results show that using a 10‐W Wolfspeed GaN HEMT device, a highly efficient broadband Class‐J PA is realised from 1.4 to 2.4 GHz (fractional BW = 52.6%) with measured drain efficiency of 63.0–68.9% and output power of 39.8–40.3 dBm.

Highly efficient wideband parallel‐circuit class‐E/F 3 power amplifier's design methodology

“…The proposed PA would be a good choice for realising high-efficiency broadband power amplification for broadband communication systems. [9] 2540-2780 9.0 38.4-40.5 60.0-83.9 PC E/F 3 [14] 1400-2400 52.6 39.8-40.3 63.0-68.9 J [15] 1350-2500 60.0 41.0-42.5 68.0-82.0 CCF −1 [16] 550-950 53.0 >40.0 >70.0 CCF [17] 1400-2700 63.0 39.7-41.5 63.0-73.0 E [18] 1240-2420 64.5 37.0-39.9 70-86 X [19] 2200-2800 24.0 41.0-43.0 65.9-79.7 BJF −1 this work 350-730 70.4 36.0-40.9 60.1-80.5 PC E/F 3…”

“…In Table 1, it is summarised that a performance comparison of published efficient broadband PAs using the same device [7-9, [14][15][16][17][18][19] along with the design presented in this paper is shown. In this case, the 'friendliness' of this device will not be a significant factor and every DB PA can be treated equally.…”

“…In terms of efficiency, it is predominantly determined by the power amplifier (PA), which is the critical power consumption component in the mobile communication system [2]. With recent trends, it is becoming urgent to develop design methodology and amplifier's architectures for broadband and high-efficiency PAs [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19].…”

Design of high‐efficiency continuous resistive‐reactive class‐J power amplifier

“…The comparison between this work and some related PAs is shown in Table 1. CGH40010F GaN HEMT is used in the References 9‐14 in Table 1, and drain bias voltage is set to 28 V, reference 15 uses CGH27015F GaN HEMT with 30 V drain voltage. Rogers corporation RT5880 duriod substrate is used in Reference 12, and the rest of them in Table 1 developed on Rogers substrate RO4350B.…”

“…To overcome the limitation of bandwidth, continuous PAs are proposed and proved 6,7 . By introducing factors in the drain voltage expression, continuous PA has a series of fundamental and second harmonic impedance solutions making up the solution space, which increases matching network design flexibility and expands the bandwidth of PA. Several class‐J PAs are proposed in 8‐10 their drain voltages are controlled to the second harmonic and there are no open circuit requirements, compared with the class‐F PA, the design difficulty of the output matching network is reduced. When the bandwidth of the PA exceeds one octave, the frequencies above the octave is both the fundamental and second harmonics, the impedances at these frequencies cannot satisfy both conditions.…”