並列共振型入力2倍波処理回路を用いたX帯高効率GaN高出力増幅器

摘要

A novel harmonic-terminating network is proposed for high-power amplifier. It consists of an inter-digital capacitor and a transmission line, which are connected in parallel and constitute a pseudo-distributed parallel-resonant network. This network contributes to increase efficiency of the power amplifier, with more compact circuit size and a wider operating frequency, compared to a conventional network utilizing a quarter-wavelength open-circuited stub. Furthermore, an X-band GaN high-power amplifier has been developed with aforementioned harmonic-terminating network at its input. In its measurements, output power of 42 - 44 [dBm] and power-added efficiency (PAE) of 50 - 51 % have been obtained in 10 % bandwidth. We believe that this performance is mostly the top in the state-of-the-art on X-band GaN high-power amplifiers with more than 10 % operating bandwidth.%増幅器の効率向上のために用いられる高調波処理回路として，インターデジタルキャパシタと伝送線路の並列接続からなる並列共振型の準分布定数回路を提案し，同回路をFETの入力側2倍波処理回路として用いたx帯高効率GaN高出力増幅器の試作結果について述べる．提案する高調波処理回路は，従来の1／4波長スタブを用いる高調波処理回路に比べて回路寸法が小型となり，また増幅器の広帯域化を図れるという利点を有している．また試作したX帯GaN高出力増幅器において，比帯域幅10％にわたり出力電力42-44[dBm]，電力付加効率50-51％の特性を得た．