A 1.8 GHz wideband high power amplifier with flat gain response by exploiting microstrip high‐pass‐filter

Abstract

A 1.8 GHz broadband high power amplifier (PA) with 144% fractional bandwidth is presented in this article. The proposed PA achieves a power added efficiency of 40%–56% for the entire band. To ensure flat gain response, a novel idea of integrating a microstrip high pass filter (HPF) in the input matching network is proposed. The incorporation of HPF reduces the unusual high gain at low frequency and thus results in a flat gain of 14.4 ±1 dB for the entire band. The matching circuits are realized on Taconic RF35 with dielectric constant of 3.5 and thickness of 0.76 mm. The high fractional bandwidth of the proposed PA makes it suitable to be used for the recent and future wireless communication systems.

Broadband power amplifier using hairpin bandpass filter matching network

“…In [3], a microstrip BPF with more than 20% fractional bandwidth (FBW) is employed as the PA OMN with good frequency selectivity. In [4], a high‐pass filter is used in the input matching network to provide flat gain and extended bandwidth over the entire band. A PA based on a hairpin filter matching network is already analysed in our previous work [5].…”

“…can cause sufficient degradation in the overall structure. For this reason, several co-designs of PAs and BPFs have been proposed to compensate for such losses [1][2][3][4][5]. Likewise, in [1,2], a co-design of high-selectivity cavity resonators are employed in Class-F PA.…”

Design of L-S band broadband power amplifier using microstip lines

“…However, this scheme is good for VSWR performance and gain flatness up to about a two octave bandwidth [21][22]. On the other hand, the traveling-wave and distributed amplifiers have flat gain and wide frequency range, but the main drawbacks for these techniques reside in the moderate small signal gain, high dc power consumption, high noise figure and the large chip size owing to the high number of components used to achieve the same performance as a single stage PA [24][25][26].…”