An <i>X</i>-Band 6-bit Active Vector-Modulated Phase Shifter With 0.29° rms Phase Error Using Linearization Control Technique

Abstract

This letter presents a 6-bit active vector-modulated phase shifter (VMPS) with a linearization control technique, which is implemented in a 0.13- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu \text{m}$ </tex-math></inline-formula> silicon-on-insulator (SOI) process. The improved balun structure and capacitance compensation polyphase filter (C-PPF) are used to achieve broadband matching and reduce orthogonal network loss while preserving orthogonal balance. A nonlinear digital-to-analog converter (DAC) cancels out the nonlinearity of a vector modulator (VM) and achieves linear control of the amplitude and phase. The VM core consists of variable gain amplifiers (VGAs) based on Gilbert cell architecture. The measured phase shifter shows minimal rms phase error of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${ &lt; }0.29^{\circ }$ </tex-math></inline-formula> and rms gain error of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${ &lt; }0.24$ </tex-math></inline-formula> dB, and the insertion loss is 0.8–3.1 dB, respectively in <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$X$ </tex-math></inline-formula> -band. The total power consumption is 90 mW with a 2.5 V supply voltage and occupies a core area of 0.92 mm2 excluding pads.