The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
This paper compares three different procedures for characterising the Noise Temperature and Conversion Loss of a millimetre wave mixer. To carry out this study a 183 GHz sub-harmonic mixer has been measured using three alternative procedures, i.e. the “Attenuator”, the “Gain” and the “Noise injection” procedures. Furthermore for every measurement procedure three different detection methods have been...
High-TC hot electron bolometers (HEB) are promising THz mixers due to their expected wide bandwidth, large mixing gain and low intrinsic noise. In this paper, we have simulated the DC characteristics, conversion loss and noise of YBaCuO HEBs with a hot spot model usually dedicated to low-TC devices.
We report on our waveguide hot electron bolometer (HEB) mixer development for the heterodyne focal plane array receiver upGREAT, which is the multi-pixel extension to the German Receiver for Astronomy at Terahertz frequencies (GREAT) currently in operation on the Stratospheric Observatory for Infrared Astronomy (SOFIA). We will present results for our new generation of HEB mixers for operation at...
A fundamental 1.9–2.8 THz Schottky diode mixer has been modified to enable high harmonic mixing, thus allowing use of the mixer for phase locking of a quantum cascade laser (QCL) to an stable external microwave source. Phase locking to a reference will transfer the spectral line profile of the reference to the THz source; this will control the phase precisely. Stabilizing a QCL for a single frequency...
To extend the frequency range of existing short-range radar modules for industrial applications, millimeter-wave frequency multipliers based on cost-effective PCB technology are required. This paper describes a zero-bias D-band frequency doubler and Y-band frequency tripler based on pure PTFE material and the commercially available DBES105a diode from United Monolithic Semiconductors (UMS). At an...
This paper reviews different mechanisms of saturation in SIS mixers and presents results of the modeling and experimental verification of the proposed solution to increase the saturation level by de-tuning the SIS mixers, to allow solar observations with ALMA.
We report on a phase locking experiment of a 3.4 THz Quantum Cascade Laser (QCL) by using only room temperature electronics. A super-lattice harmonic mixer was used to produce a bit signal between the QCL signal and the 18th harmonic of a 190 GHz reference generator. The beat signal more than 30 dB above the noise level for 1 MHz RBW was observed. Such a signal to noise ratio was sufficient to provide...
Local oscillator (LO) sideband noise suppression by a balanced superconductor-insulator-superconductor (SIS) mixer was investigated in the 0.9 THz band. An LO signal in the 0.9 THz band was generated by using fixed tuned x9 (x3 by x3) multipliers located in the cryostat 4-K stage. Despite the huge LO noise of about 1000 K of a YIG driven LO, the measured receiver noise temperature for YIG and Gunn...
This article describes a 16QAM modulation based 3Gbps wireless communication demonstration system at 0.34 THz band, which consists of a 0.34 THz wireless communication transceiver front end based on solid-state semiconductor, an IF updown converter, and a digital signal process unit. The transmitted signal carrier of this demonstration system is centered at 0.34 THz, the output power is −20dBm, the...
In this work the results of spectroscopic and performance measurements with a compact heterodyne receiver in the frequency range between 520 and 590 GHz are presented.
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.