A Full 360$^{\circ}$ Vector-Sum Phase Shifter With Very Low RMS Phase Error Over a Wide Bandwidth

Abstract

An innovative vector-sum phase shifter with a full 360 variable phase-shift range in 0.18-m CMOS technology is proposed and experimentally demonstrated in this paper. It employs an I/Q network with high I/Q accuracy over a wide bandwidth to generate two quadrature basis vector differential signals. The fabricated chip operates in the 2.3-4.8 GHz range. The root-mean-square gain error and phase error are less than 1.1 dB and 1.4 over the measured frequency span, respectively. The total current consumption is 10.6 mA (phase shifter core: 2.6 mA) from a 1.8 V supply voltage and overall chip size is 0.87 0.75 mm . To the best of the authors' knowledge, this circuit is the first demonstration of microwave CMOS phase shifter with very low phase error over a wide bandwidth employing the vector sum method for all monolithic microwave integrated circuit phase shifters with 360 phase-control range to date.Index Terms-Active phase-shifter, CMOS analog integrated circuit, differential amplifier, I/Q network, phased array.

X-Band 6-Bit Phase Shifter with Low RMS Phase and Amplitude Errors in 0.13-㎛ CMOS Technology

“…The vector-modulator and switched-filter topologies in Fig. 1(b) and (c) are widely used in silicon-based phase shifters [5][6][7][8]. The active vector-summing phase shifter has a compact size and high accuracy with digital calibration circuits.…”

“…However, this type of phase shifter operates only in one direction. In addition, it has non-zero DC power consumption and lower linearity than the phase shifters using the switches due to the analog amplifiers [5].…”

A 6-bit phase shifter with low RMS phase error and flat gain across 1.9–2.6GHz

“…The active phase shifter should keep low RMS phase error, a large RMS phase error will limit the application [3] [4] [5] [6] .…”

A 0.5–6 GHz 360° vector-sum phase shifter in 0.13-µm CMOS

“…The vector-sum phase shifter can provide continuous phase control for a 3600 phase range [1]- [3]. Conventional approaches use an input balun and a 900 coupler for the full-3600 phase shifting, since four quadrature signals (Iin+' Iin+ and Qin+, Qin-) are required to be added with appropriate I1Q amplitudes and polarities [1]- [3].…”