Proposed Down-conversion Mixer Research Articles

Linearity improvement in a CMOS down-conversion active mixer for WLAN applications

This paper presents an active down-conversion mixer for wireless local area network applications. The proposed down-conversion mixer is designed for 2–3 GHz radio frequency (RF) band and an intermediate frequency of 100 MHz using RF-TSMC CMOS 0.18 μm technology. A new fully differential Darlington cell is introduced in the RF transconductance stage to effectively suppress third-order nonlinearity. In addition, the conversion gain and noise performance of the proposed mixer are improved by using an active load and current bleeding technique. The proposed mixer has been simulated by Cadence Spectre-RF. Post-layout simulation results show the third-order input intercept point can be improved up to 12.5 dBm by optimum biasing of the Darlington cell. The proposed mixer achieves the high conversion gain of 14.5 dB and the low double side-band noise figure of 4.55 dB at the input frequency of 2.4 GHz. The mixer operates at the supply voltage of 1.8 V with power consumption of 17.4 mW.

A W-band CMOS down-conversion mixer using CMOS-inverter-based RF GM stage for conversion gain and linearity enhancement

A W-band (75–110 GHz) down-conversion mixer with CMOS-inverter-based RF transconductance (GM) stage for 94 GHz image radar sensors in 90 nm CMOS is reported. Due to the current bleeding and GM contribution of the upper PMOS transistors of the RF GM stage, a larger load resistance can be adopted and a larger GM can be obtained while keeps the same linearity. This leads to a conversion gain (CG) enhancement. In addition, the second-order term GM (g2) and third-order term GM (g3) of the main NMOS transistors of the RF GM stage can be cancelled by those of the upper PMOS transistors and the auxiliary NMOS transistors of the RF GM stage. This leads to a better linearity. The mixer consumes 8.56 mW and achieves an excellent RF-port input reflection coefficient of − 10 to − 18 dB for frequencies of 88.4–103.4 GHz. In addition, for frequencies of 70–100 GHz, the mixer achieves CG of 13.9–17.5 dB and LO-RF isolation of 40.6–43.5 dB, one of the best CG and LO-RF isolation results ever reported for a down-conversion mixer with operation frequency around 94 GHz. Furthermore, the mixer achieves prominent NF of 16.4 dB and output third-order intercept point of 14.1 dBm at 94 GHz. These results demonstrate that the proposed down-conversion mixer architecture is very promising for 94 GHz image radar sensors.

94 GHz down-conversion mixer with gain enhanced Gilbert cell in 90 nm CMOS

A 94 GHz down-conversion mixer for image radar sensors using standard 90 nm CMOS technology is reported. The down-conversion mixer comprises a double-balanced Gilbert cell with an LC-tank-oscillator-based RF transconductance stage load for conversion gain (CG) enhancement and noise figure (NF) suppression, two miniature planar baluns for converting the single RF and LO input signals to differential signals, and an IF amplifier. The mixer consumes 9.5 mW and achieves excellent RF-port input reflection coefficient (S11) of −27.2 dB at 94 GHz, and S11 smaller than −10 dB for frequencies of 83.6–110 GHz. That is, RF-port −10 dB input matching bandwidth is greater than 26.4 GHz. In addition, for frequencies of 75–100 GHz, the mixer achieves CG of 4.9–7.9 dB (the corresponding 3-dB CG bandwidth is greater than 25 GHz), LO–RF isolation of 38.5–44.7 dB and NF of 15.4–21.2 dB, one of the best CG, LO–RF isolation and NF results ever reported for a down-conversion mixer with operation frequency around 94 GHz. Furthermore, the mixer achieves an excellent input third-order intercept point of 2.6 dBm at 94 GHz. These results demonstrate the proposed down-conversion mixer architecture is promising for 94 GHz image radar sensors.

A 90–96 GHz CMOS down-conversion mixer with high conversion gain and excellent LO–RF isolation

A 90–96 GHz down-conversion mixer for 94 GHz image radar sensors using standard 90 nm CMOS technology is reported. RF negative resistance compensation (NRC) technique, i.e. NMOS LC-oscillator-based RF transconductance (GM) stage load, is used to increase the output impedance and suppress the feedback capacitance Cgd of RF GM stage. Hence, conversion gain (CG), noise figure (NF) and LO-RF isolation of the mixer can be enhanced. The mixer consumes 15 mW and achieves excellent RF-port input reflection coefficient of −10∼−36.4 dB for frequencies of 85∼105 GHz. The corresponding −10 dB input matching bandwidth is 20 GHz. In addition, for frequencies of 90∼96 GHz, the mixer achieves CG of 6.3∼9 dB (the corresponding 3-dB CG bandwidth is greater than 6 GHz) and LO-RF isolation of 40∼45.1 dB, one of the best CG and LO-RF isolation results ever reported for a down-conversion mixer with operation frequency around 94 GHz. Furthermore, the mixer achieves an excellent input third-order intercept point (IIP3) of 1 dBm at 94 GHz. These results demonstrate the proposed down-conversion mixer architecture is very promising for 94 GHz image radar sensors.

Design and implementation of a 94 GHz CMOS down-conversion mixer with integrated miniature planar baluns for image radar sensors

A 94 GHz down-conversion mixer for image radar sensors using standard 90 nm CMOS technology is reported. The down-conversion mixer comprises a double-balanced Gilbert cell with peaking inductors between RF transconductance stage and LO switching transistors for conversion gain (CG) enhancement and noise figure suppression, a miniature planar balun for converting the single RF input signals to differential signals, another miniature planar balun for converting the single LO input signals to differential signals, and an IF amplifier. The mixer consumes 22.5 mW and achieves excellent RF-port input reflection coefficient of ź10 to ź35.9 dB for frequencies of 87.6---104.4 GHz, and LO-port input reflection coefficient of ź10 to ź31.9 dB for frequencies of 88.2---110 GHz. In addition, the mixer achieves CG of 4.9---7.9 dB for frequencies of 81.8---105.8 GHz (the corresponding 3-dB CG bandwidth is 24 GHz) and LO---RF isolation of 37.7---47.5 dB for frequencies of 80---110 GHz, one of the best CG and LO---RF isolation results ever reported for a down-conversion mixer with operation frequency around 94 GHz. Furthermore, the mixer achieves an excellent input third-order intercept point of ź3 dBm at 94 GHz. These results demonstrate the proposed down-conversion mixer architecture is promising for 94 GHz image radar sensors.

A +12-dBm OIP3 60-GHz RF Downconversion Mixer With an Output-Matching, Noise- and Distortion-Canceling Active Balun for 5G Applications

A CMOS millimeter-wave (mmWave) downconversion mixer with a local-oscillator (LO) buffer is proposed for wireless Gb/s data-transfer enabling systems, such as 5G systems. To obtain high linearity at low supply voltages, the proposed mmWave downconversion mixer adopts an on-chip transformer-based topology. In order to achieve differential to single-ended conversion and IF output matching, while maintaining a high linearity performance, the proposed mmWave downconversion mixer incorporates an active balun with common-source and common-drain configurations employing common-mode noise and third-order intermodulation distortion cancellations. The proposed downconversion mixer with active balun and LO buffer was implemented using a 65-nm CMOS process and it draws 18 mA from a 1 V supply voltage. It demonstrates a gain greater than 5.6 dB, noise figure less than 10.9 dB, and third-order output intercept point more than 12.4 dBm, in the band from 57 to 66 GHz.

Ultra low power wide-band mixer circuit based on subthreshold operation for MB-OFDM UWB

This paper presents an extremely low power down-conversion mixer based on subthreshold operation for MB-OFDM UWB receiver, for the first band of operation 3.1–3.628GHz. The proposed down-conversion mixer uses a double balanced Gilbert cell to provide the required performance in the conversion gain (CG) and the isolation among ports. It includes an input matching network (IMN) to enhance the input matching of the mixer. The proposed mixer is designed such that all transistors work in subthreshold regime under a supply voltage of 0.5V, thus resulting in extremely low power consumption. We implemented the proposed mixer using a 0.18μm CMOS process. Simulation experiments show that the conversion gain of the mixer is 2.17–3.25dB over the frequency range of 3.1–3.628GHz when IF port is terminated with 50Ω. The noise figure of the mixer is 5.12–5.93dB, while the LO-IF isolation is lower than −111dB. The 1-dB compression point is −16.68dBm, third-order input intercept point IIP3 is −5.7dBm. The experiments show that the proposed design consumes only 6.6uW at 0.5V, which is extremely low power compared with existing work.

A D-Band Gain-Boosted Current Bleeding Down-Conversion Mixer in 65 nm CMOS for Chip-to-Chip Communication

A D-band gain-boosted current-bleeding down-conversion mixer is presented in this letter using 65 nm CMOS technology. The proposed downconversion mixer uses a gain-boosted current-bleeding technique to improve the conversion gain for low power chip to chip communication with a low local oscillator (LO) power. Broadband Marchand baluns were used to transform a single-ended signal to a differential signal at the RF and LO port for measurement. According to experimental results, the proposed mixer had a measured conversion gain of -12 ± 1 dB at a frequency range from 113 to 127 GHz with an ultra-low LO power of -9 dBm using a gain-boosted current bleeding technique. The LO-to-RF isolation was better than -30 dB. This core chip occupies 350 × 320 μm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> . The power consumption is 6 mW from a 1 V supply voltage.

A 60-GHz CMOS Down-Conversion Mixer with Current-Reused RF Single-to-Differential Converter and Integrated Marchand Balun

A 60-GHz double-balanced mixer for direct down-conversion using standard 90-nm CMOS technology is reported. The down-conversion mixer comprises a double-balanced Gilbert cell with a current-reused RF single-to-differential converter for conversion gain (CG) enhancement, a Marchand balun for converting the single LO input signal to differential signal, and a baseband amplifier. The mixer consumes 17 mW and achieves low noise figure of 12.8 dB at 60 GHz. In addition, the mixer achieves excellent LO-RF isolation of 64.7 dB, LO-IF isolation of 51.5 dB, and RF-IF isolation of 59.5 dB at RF of 60 GHz and LO of 59.9 GHz. At IF of 0.1 GHz, the mixer achieves maximum CG of 15.46 dB at RF of 62 GHz, and CG of 14.7 dB at RF of 60 GHz, one of the best CG results ever reported for a 60-GHz CMOS down-conversion mixer. The corresponding 3-dB bandwidth of RF is 5.4 GHz (58.7–64.1 GHz). These results demonstrate the proposed down-conversion mixer architecture is very promising for 60-GHz direct-conversion transceiver applications. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1937–1946, 2013

A low-noise mixer with an image-reject notch filter for 2.4 GHz applications

This paper presents a low noise first down-conversion mixer with a notch filter for the heterodyne receiver. The notch filter connected to the output node of the mixer driver stage plays a role of image rejection at an image frequency, thereby suppressing the sideband image noise and improving the mixer noise performance. Targeted for 2.4 GHz industrial–scientific–medical band applications, a simple source-degenerated down-conversion single balanced mixer with the filter is implemented. The measurement results of the proposed down-conversion mixer shows about 3.0 dB improvement of single-side band noise figure, about 2.9 dB power conversion gain improvement, and 25 dB image suppression compared to those without the filter dissipating 4 mA from a 2.5 V supply voltage.