This letter presents a WR-3.4-band reflection-type phase shifter (RTPS) in a 250-nm InP double heterojunction bipolar transistor (DHBT) technology. A reflective load with an L-section network is implemented using a diode-connected transistor, a transmission line, and a shunt capacitor. The reference impedance of the reflective load is set to a low impedance of 30 $\Omega $ , thus leading to a low-loss variation over a wide operating bandwidth. To minimize the chip area, a quadrature hybrid for combining reflected signals is implemented using a compact broadside coupled-line coupler. The measurement shows that the RTPS provides a continuous 180° phase shift with an average insertion loss of 9.9–10.9 dB over a frequency range from 275 to 320 GHz. The loss variation is only 1 dB. The root-mean-squared (RMS) amplitude and phase errors maintain below 2.9 dB and 7.3°, respectively. The chip size including all probing pads is as small as $0.37\times0.46$ mm², and the core size is only 0.02 mm². The dc power consumption is zero.

中文翻译：

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紧凑型 275–320-GHz 反射型移相器

这封信介绍了采用 250 纳米 InP 双异质结双极晶体管 (DHBT) 技术的 WR-3.4 波段反射型移相器 (RTPS)。使用连接二极管的晶体管、传输线和并联电容器来实现具有 L 截面网络的反射负载。反射负载的参考阻抗设置为 30 $\欧米茄$，从而导致在宽工作带宽上的低损耗变化。为了最小化芯片面积，使用紧凑型宽边耦合线耦合器实现了用于组合反射信号的正交混合。测量结果表明，RTPS 在 275 至 320 GHz 的频率范围内提供连续 180° 相移，平均插入损耗为 9.9–10.9 dB。损耗变化仅为 1 dB。均方根 (RMS) 幅度和相位误差分别保持在 2.9 dB 和 7.3° 以下。包括所有探测焊盘在内的芯片尺寸小至 $0.37\times0.46$mm ²，磁芯尺寸仅为0.02 mm ²。直流功耗为零。