SiGe BiCMOS high‐gain and wideband differential intermediate frequency amplifier for W‐band passive imaging single‐chip receivers

Abstract

This study presents the results of a high-gain and wideband differential intermediate frequency (IF) amplifier circuit design for a W-band passive imaging single-chip (down-conversion) receiver front-end. The cascaded two-stage IF amplifier was fabricated in a 0.13 μm SiGe BiCMOS process technology with 300 GHz/500 GHz f T /f max . In total six on-chip inductors are used in the input, output and inter-stage matching networks which enable relatively broadband RF properties together with a compact circuit size for the IF amplifier (the die area is 0.27 mm 2 incl. RF and DC pads). The broadband SiGe amplifier has a measured gain of 10-19.5 dB at 2-37 GHz (|s 11 | and |s 22 | ≤ −10 dB at 7-40 GHz and 8-35 GHz, respectively), noise figure of 6.3-8.0 dB at 2-26 GHz and output third order intercept points of 7-17 dBm at 1-40 GHz (the DC power consumption is 122 mW). To the authors' best knowledge, this work reports a first-time realisation of a differential IF amplifier made in a 0.13 μm SiGe BiCMOS technology that achieves such wideband impedance matching together with a high gain and reasonably low noise properties over a wide instantaneous bandwidth (|s 21 | = 15-19.5 dB at 3-26 GHz).

5–35 GHz broadband if amplifier section in 0.13 μm SiGe technology for W‐band heterodyne receiver RFICs

“…Finally, the active and passive parts were combined in Cadence incl. the EM simulated s ‐parameter files of the on‐chip inductors . The circuit layout of the IF detector was done in Cadence and simulations in ADS.…”

“…Feedback resistors are used in each stage to ensure unconditional stability of the amplifier ( R f1 = 240 Ω, R f2 = 550 Ω). The DC biasing voltages V b1 , V b2 , V c1 , and V c2 are applied via the resistors R b1 , R b2 , R c1 , and R c2 . Two pairs of transistors Q 1 , Q 2 and Q 3 , Q 4 ( n = 4) are used in the detector for temperature compensation [see Fig.…”

“…The main benefit of using a heterodyne architecture instead of a direct‐detection receiver is that a higher receiver gain and sensitivity can be obtained more easily if a high‐gain IF amplifier is used after the mixer, and hence, the LNA/detector gain/sensitivity requirements can be relaxed. To fulfil the receiver component requirements of a targeted W‐band passive imaging system, the IF amplifier should have a gain of 15–20 dB (NF of 5–10 dB) and the detector NEP should be maximum 10 pW/Hz 1/2 over a receiver bandwidth of 25 GHz, respectively . Relatively few results have been presented with respect to silicon‐based wideband IF amplifier and power detector circuits for system‐on‐chip (SoC) W‐band radiometers .…”

Design of a high‐gain silicon BJT and an E‐pHEMT hybrid matrix amplifier with an optimum filter‐matching technique

“…Differential amplifiers offer wide bandwidth and high gain. Three configurations were proposed with 10-11.5, 10-19.5, and 10-18.7 dB gains across 2-39, 2-37, and 2-36 GHz band, respectively, with 26, 122, and 70 mW of P dc , respectively [16].…”