Fourth-harmonic Mixer Research Articles

Design of a 2.5 THz Schottky-Diode Fourth-Harmonic Mixer

Design of a 2.5 THz Schottky-Diode Fourth-Harmonic Mixer

A 77-GHz Low-Conversion-Loss Fourth-Harmonic Mixer on SISL Platform

This letter presents a 77-GHz low-conversion-loss (CL) fourth-harmonic mixer based on the substrate-integrated suspended line (SISL) platform. Based on the traditional stub-type harmonic mixing structure, we add several additional transmission lines, which will participate in the impedance matching of the diode together with stubs to reduce the CL. A 3-D electromagnetic (EM) diode model is established for accurate simulation at millimeter-wave frequency. The presented SISL mixer was fabricated by the low-cost printed circuit board (PCB) process and was self-packaged in FR4 substrates. When the local oscillator (LO) frequency is 19.45 GHz and the radio frequency (RF) is 78 GHz, the minimum CL is 12.2 dB under an LO input power of 12 dBm. This mixer is suitable for 77-GHz automotive anti-collision radar systems.

A Millimeter-Wave 4th-Harmonic Schottky Diode Mixer with Integrated Local Oscillator

In this paper the design and experimental validation of a fourth-harmonic mixer based on Schottky diodes working around 300 GHz is presented. The main novelty of this work consists in the integration of an MMIC-based local oscillator, working around 75 GHz, and a mixer in the same metallic block housing. A prototype has been characterized using the Y-Factor method and yields a best measured conversion loss and an equivalent noise temperature of 14 dB and 9600 K, respectively. This performance is comparable to the state-of-the-art for this type of mixer.

High-<italic>T<sub>c</sub> </italic> Superconducting Fourth-Harmonic Mixer Using a Dual-Band Terahertz On-Chip Antenna of High Coupling Efficiency

This paper presents a dual-band on-chip antenna-coupled high- Tc superconducting (HTS) Josephson-junction subterahertz (THz) fourth-harmonic mixer. The antenna utilizes a couple of different structured twin slots to enable the resonant radiations at two frequencies, and integrates a well-designed coplanar waveguide network for achieving good radiation coupling and signal isolation characteristics. The electromagnetic simulations show that coupling efficiencies as high as −4 and −3.5 dB are achieved for the 160- and 640-GHz operating frequency bands, respectively. Based on this dual-band antenna, a 640-GHz HTS fourth-harmonic mixer is developed and characterized in a range of operating temperatures. The mixer exhibits a measured conversion gain of around −18 dB at 20 K and −22 dB at 40 K, respectively. The achieved intermediate frequency bandwidth is larger than 23 GHz. These are the best results reported for HTS harmonic mixers at comparable sub-THz frequency bands to date.

Wideband Fourth-Harmonic Mixer Operated at 325–500 GHz

This letter presents an approach to design the fourth-harmonic mixer based on a pair of antiparallel Schottky diodes. To implement the proposed fourth-harmonic mixer, a two-level local oscillator (LO) low-pass filter is used to suppress the second, third, and fourth harmonics of the LO frequency, further to improve the isolation between RF and LO ports. Also, two shorted grounds are adopted to ensure the wideband performance of the proposed mixer. Furthermore, a wideband fourth-harmonic operating at 325–500 GHz is fabricated and measured. The results show that it has very low conversion loss from 15 to 22 dB in the whole operational band.

Tunable fourth LO‐harmonic mixer using CRLH‐TL and varactor diode

AbstractA novel fourth order harmonic mixer using composite right/left handed transmission lines and varactor diode is presented.The structure provides more flexible phase for suppressing spurious signals and improving conversion loss. Compared with conventional harmonic mixer, the measured results show that 10.4 dB conversion loss and 80 dB suppression of unwanted harmonics are achieved when local oscillator signal power is 7 dBm at 5 GHz. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:543–545, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26575

A CMOS 1.6 GHz Dual-Loop PLL With Fourth-Harmonic Mixing

A 1.5-1.6 GHz dual-loop phase-locked loop in 0.18-μm CMOS locks in 40 μs and draws only 26 mA from 1.8 V. The proposed techniques include a fourth-harmonic mixer that relaxes the secondary PLL requirements, and an auxiliary charge pump that speeds acquisition without affecting steady-state operation. The integrated RMS phase error is 1.1° and the phase noise spectral density is -116.8 dBc/Hz at an offset frequency of 600 kHz. The largest in-band and reference spurs are -83 dBc and -105 dBc at frequency offsets of 500.5 kHz and 37.9 MHz, respectively.

Research on Fourth Harmonic Mixer at W Band in the Imaging System

This paper presents a novel fourth harmonic mixer with new structure. The traditional 3-ports fourth harmonic mixer and the novel fourth harmonic mixer are designed by ADS, HFSS and CST simulator. The mixers have been fabricated and tested. The size of the traditional 3-ports fourth harmonic mixer is 12×15 ㎜, and the best conversion loss is 18.7 ㏈ according to the measurement. Since the traditional 3-port mixer size is too large to be ranked, we design a novel fourth harmonic mixer for imaging system. The width of the mixing module in the novel fourth harmonic mixer is only 3.65 ㎜, and this size is fully capable to meet the mixer unit space which is not greater than 5 ㎜. The simulation result shows that the mixer has good performance, and the experiment result shows that the best conversion loss of the novel fourth harmonic mixer is 16.3 ㏈ at RF signal of 91.3 ㎓.

Ka Band Broadband Fourth Harmonic Image Rejection Mixer

This paper presents the design and implementation of Ka band broadband hybrid integrated image rejection mixer with a fourth harmonic mixer as unit mixer. Detailed design and analysis have been carried out. The mixer was fabricated by hybrid microwave integrated circuit (HMIC) process based on the thin film ceramic substrate which can reduce the cost compared to monolithic microwave integrated circuit (MMIC). The measured results showed conversion loss less than 11.2 dB and image rejection ratio (IRR) more than 20 dB in 4 GHz RF bandwidth. It can also play the role of up-converter from the test data.