Shih Han Hung

High-Isolation Millimeter-Wave Subharmonic Monolithic Mixer With Modified Quasi-Circulator

This study presents a 21-40-GHz broadband subharmonic gate-pumped mixer using the standard 0.18-μ m CMOS process. A modified quasi-circulator is monolithically integrated with an nMOS field-effect transistor to perform down-converter mixing while enhancing all port isolations through a broadband operation. The proposed configuration has a chip size of less than 0.9 mm2. The measured results demonstrate a low conversion loss from 8.3 to 14.2 dB, a local oscillation (LO)-to-RF isolation greater than 50 dB, and a high 2LO-to-RF isolation of 48 dB to 65 dB over the 21-40-GHz RF bandwidth at a 10.5-dBm LO power level.

A Miniature Millimeter-Wave Monolithic Star Mixer with Simple if Extraction Circuit

A novel millimeter-wave monolithic double balanced mixer with a simple IF extraction circuit is demonstrated through a 0.25 μm GaAs PHEMT process. This mixer consists of 180-degree hybrid and dual Marchand baluns to achieve the new diode arrangement with phase relationships. Compared with the conventional double balanced mixers, it provides not only flexible layout design, but also the convenience of IF extraction. Measured results with a conversion loss of 10.3 ∼ 14.7 dB, a LO-to-IF and RF-to-IF isolation better than 24.2 dB from 29 to 40 GHz, and a chip dimension as small as 0.8 × 1.75 mm2 can be achieved.

An Ultra-Broadband Subharmonic Mixer With Distributed Amplifier Using 90-nm CMOS Technology

This paper presents a Ka- to F-band ultra-broadband subharmonic mixer (SHM) using the standard 90-nm CMOS process. The proposed SHM employs a distributed amplifier and antiparallel diode pair configuration to realize wide operation bandwidth from 33 to 103 GHz, low conversion loss from 0.52 to 3.35 dB, good local oscillation (LO)-to-RF isolation greater than 27.7 dB, and high 2LO-to-RF isolation better than 60 dB with a miniature chip dimension of 0.49 mm2 at a 10-dBm LO power level. Using the distributed amplifier technique, the proposed SHM offers significant advantages, such as broad operation bandwidth, good flatness, high port-to-port isolation, and good conversion loss.

An Ultra Wideband Quasi-Circulator With Distributed Amplifiers Using 90 nm CMOS Technology

An ultra wideband (UWB) quasi-circulator implemented with distributed amplifiers using the 90 nm complementary metal-oxide-semiconductor (CMOS) technology is presented. The proposed quasi-circulator is composed of two distributed amplifiers and two Lange couplers to attain UWB performance at 14 to 67 GHz. Good insertion gain of 4.3 dB to -3.5 dB, low noise figure of 7.1 to 12.6 dB, and good isolation characteristic of |S31| better than 20 dB can be obtained. Using the distributed amplifier technique, the proposed quasi-circulator offers significant advantages of broad operation bandwidth, high isolation, low noise figure, and good insertion gain.

Broadband sub-harmonic mixer with a compact band pass filter

This paper presents a 28 GHz to 72 GHz isolation enhanced down-conversion broadband sub-harmonic mixer using the 0.15 μm GaAs pHEMT process with chip dimensions of 1.8 × 0.76 mm2. The configuration of the sub-harmonic mixer consists of one intermediate frequency (IF) amplifier, one compact band pass filter, and one Lange coupler utilizing an anti-parallel diode pair (APDP). To reduce line length and achieve broad operation bandwidth, the proposed grounded capacitor in the band pass filter can also enhance the local oscillation (LO)-radio frequency (RF) isolation of the sub-harmonic mixer. Both high conversion gain and isolation can be achieved between LO and RF-IF in the IF amplifier. The measured results indicate that the conversion gain of the mixer is 5.02 dB to 11.5 dB from RF frequency of 28 GHz to 72 GHz at the LO power of 9 dBm; the isolation of RF-IF, LO-IF, LO-RF, and 2LO-RF is 21 dB to 51.52 dB, 22.13 dB to 30.97 dB, 10.64 dB to 27.9 dB, and 48.9 dB to 72.35 dB, respectively.

A Novel Post-Linearization Technique for Fully Integrated 5.5 GHz High-Linearity LNA

A novel post-linearization technique for fully integrated 5.5 GHz high-linearity LNA, implemented through a 0.18 mum RF CMOS technology, is demonstrated. The post-linearization technique adopts a folded cascode diode with a resistor and a capacitor in parallel as a third-order intermodulation distortion (IMD3) sinker. The LNA with the post-linearization technique has a +8.33 dBm IIP3, a power gain of 10.02 dB, and a noise figure of 3.05 dB, while consuming 6 mA from a supply voltage of 1.8 V. Comparison with the characteristics of the LNA without using post-linearization technique, the IIP3 is improved 6.21 dB, and the IMD3 can be reduced 12.77 dB. Moreover, the performances of noise figure and power consumption rise 0.09 dB and 0.08 mW, and the power gain lowers 0.3 dB after using the technique only. This technique indeed improves the linearity performance without obvious effects.

Analysis of three-conductor coupled-line 180° hybrid for single-balanced subharmonic mixer design in 0.15-μ m pHEMT technology

A novel 180 ^° hybrid with two λ/4 sections of three-conductor coupled-line structure inhered different operating frequencies with overlapped characteristic and perfect isolation between the Σ-port and Δ-port is employed to implement a Ka- to M-band single-balanced subharmonic mixer (SHM) in a 0.15- μm GaAs pHEMT process with a compact die size of less than 0.82 × 0.83 mm². The thorough analysis based on the scattering matrix of the 180 ^° hybrid is also presented. Incorporating the inherent features of the 180 ^° hybrid with an antiparallel diode pair configuration, the proposed SHM achieved a wide operating bandwidth from 37 to 85 GHz with low conversion loss from 9 to 14 dB, enhanced local oscillation (LO)-to-RF isolation and 2LO-to-RF isolation under 10-dBm LO power level. This proposed architecture is really attractive to SHM design in modern millimeter-wave territory.

Compact double-balanced star mixers with novel dual 180° hybrids

Compact double-balanced monolithic star mixers using 0.25 μm GaAs pHEMT process are presented. These star mixers adopt two novel types of the dual 180° hybrid structure, thereby reducing the chip size and eliminating complex layout. With multi-coupled lines technology, the proposed dual 180° hybrids are produced and applied to star mixers successfully. Furthermore, the proposed hybrids simplifies the star mixers IF extraction circuit to reduce the chip size and enhance the IF bandwidth. The results demonstrate wide operation bandwidth, low conversion loss and good port-to-port isolations with a size dimension of less than 0.81 mm2, could thus be obtained.

Ultra-Wideband Quasi-Circulator Implemented by Cascading Distributed Balun With Phase Cancelation Technique

This paper presents the implementation of a broadband quasi-circulator through a cascading distributed balun using a 90-nm CMOS process. The isolation, |S31|, of the proposed three-port quasi-circulator can be acquired through the phase cancelation technique, by connecting an additional distributed amplifier in parallel between ports 1 and 3. The thorough analysis based on an eight-port chain matrix and scattering matrix is presented for refining the circuit parameters in the initial design. Measured results show that the proposed quasi-circulator attains a broad operation bandwidth ranging from 10 to 67 GHz. Moreover, the quasi-circulator also has good insertion gain of 0.5 to 4.8 dB, as well as isolation |S31|, which is better than 23 dB. Consequently, the proposed quasicirculator delivers wide bandwidth performance, good port-toport isolations, good insertion gain, and high linearity based on the cascading distributed balun with phase cancelation technique.

A CMOS doubly balanced monolithic ring mixer with an advanced IF extraction

A CMOS doubly balanced monolithic microwave ring mixer fabricated through 0.18 μm TSMC CMOS process is presented. The main design objective is to satisfy broadband operations with a compact and advanced IF extraction and to shrink the chip area. A miniature Marchand-like spiral balun with a low-pass filter is used to extract IF signals and maintain balun performance simultaneously. This design can mitigate layout complexity and promote port-to-port isolations. The CMOS ring DBM exhibits an operating bandwidth of 7-23 GHz at an LO power of 11 dBm with the smallest chip area of 0.76 × 0.51 mm2. Moreover, the LO/RF-to-IF isolations levels are both higher than 31 dB. This outcome is primarily caused by the utilization of an offset overlayed stacked spiral balun.