We have developed a low-noise 850 GHz superconductor–insulator–superconductor quasiparticle mixer with NbTiN thin-film microstrip tuning circuits and hybrid Nb/AlN/NbTiN tunnel junctions. The mixer uses a quasioptical configuration with a planar twin-slot antenna feeding a two-junction tuning circuit. At 798 GHz, we measured an uncorrected double-sideband receiver noise temperature of TRX5260 K...

The paper presents analysis and design of a -band subharmonic mixer (SHM) with high conversion gain. The SHM consists of a local oscillator (LO) frequency doubler, RF pre-amplifier, and single-ended mixer. The SHM has been fabricated in a high-speed InP double heterojunction bipolar transistor (DHBT) technology using coplanar waveguide structures. To the best of our knowledge, this is the first...

We characterize a heterodyne receiver based on a surface-plasmon waveguide quantum cascade laser (QCL) emitting at 2.84 THz as a local oscillator, and an NbN hot electron bolometer as a mixer. We find that the envelope of the far-field pattern of the QCL is diffraction-limited and superimposed onto interference fringes, which are similar to those found in narrow double-metal waveguide QCLs. Com...

We present a new device concept for a mixer element for THz frequencies. This uses a superconducting transition-edge microbridge biased at the center of its superconducting transition near 4.2 K. It is fed from an antenna or waveguide structure. Power from a local oscillator and a rf signal produce a temperature and resulting resistance variation at the difference frequency. The new aspect is t...

In this paper, a mixer topology selection for a multi-standard high image-reject front-end is presented. The receiver is intended to work for Digital Enhanced Cordless Telephone (DECT) systems (at 1.9 GHz and 2.4 GHz) and for Bluetooth (at 2.4 GHz). It will be implemented in 0 18 μm CMOS technology. A double-quadrature low-IF architecture is employed because it can provide a high image rejectio...

This paper describes a 2.4 GHz passive switch mixer and a 5/2.5 GHz voltage-controlled negative Gm oscillator (VCO) with an inversion-mode MOS varactor. Both circuits are implemented using a 1P8M 0.13 μm process. The switch mixer has an input referred 1 dB compression point of −3.89 dBm and a conversion gain of −0.96 dB when the local oscillator power is +2.5 dBm. The VCO consumes only 1.75 mW,...

Microfluidic designs are advantageous and are extensively used in number of fields related to biomedical and biochemical engineering. The objective of this paper is to perform numerical simulations to optimize the design of microfluidic mixers in order to achieve optimum mixing. In the present study, fluid mixing in different type of micro channels has been investigated. Numerical simulations a...