| 1. |
- Alexander, Naomi E., et al.
(författare)
-
IMAGINE project : A low cost, high performance, monolithic passive mm-wave imager front-end
- 2012
-
Ingår i: Proceedings of SPIE - The International Society for Optical Engineering. - : SPIE. - 0277-786X .- 1996-756X. - 9780819492852
-
Konferensbidrag (refereegranskat)abstract
- The FP7 Research for SME project IMAGINE - a low cost, high performance monolithic passive mm-wave imager front-end is described in this paper. The main innovation areas for the project are: i) the development of a 94 GHz radiometer chipset and matching circuits suitable for monolithic integration. The chipset consists of a W-band low noise amplifier, fabricated using the commercially available OMMIC D007IH GaAs mHEMT process, and a zero bias resonant interband tunneling diode, fabricated using a patented epi-layer structure that is lattice matched to the same D007IH process; ii) the development of a 94 GHz antenna adapted for low cost manufacturing methods with performance suitable for real-time imaging; iii) the development of a low cost liquid crystal polymer PCB build-up technology with performance suitable for the integration and assembly of a 94 GHz radiometer module; iv) the assembly of technology demonstrator modules. The results achieved in these areas are presented.
|
|
| 2. |
- Dochev, Dimitar Milkov, 1981, et al.
(författare)
-
Superconducting IF biasing circuit for low-noise cryogenic applications
- 2010
-
Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 234:4
-
Konferensbidrag (refereegranskat)abstract
- A planar superconducting circuit designed for use in low-noise cryogenic applications is presented. The circuit is a bias-T combined with a 4–8 GHz impedance matching circuitry, which employs entirely planar design with a novel layout. The proposed and tested circuitry is intended to be used with a SIS mixer and incorporates a double section transformer based on microstrip line technology with a total impedance transformation of 5:1 within the frequency band. One of the transformer sections employs a three-line coupled line, which also serves as a DC block capacitor. The microstrip lines were manufactured using superconducting Nb metallization, which provides a conduction loss-free solution at the operation temperature of 4 K. S-parameter measurements at 4 K temperature were performed and found to be in a good agreement with the simulations. The device measured return loss is better than −10 dB within the frequency band. Furthermore, the circuit was tested as a part of 385 – 500 GHz double sideband heterodyne SIS receiver demonstrating a flat noise temperature response of 80 – 90 K over the entire IF band of 4 – 8 GHz.
|
|
| 3. |
- Eriksson, Klas, 1983, et al.
(författare)
-
Design and Characterization of H-Band (220-325 GHz) Amplifiers in a 250-nm InP DHBT Technology
- 2014
-
Ingår i: IEEE Transactions on Terahertz Science and Technology. - : Institute of Electrical and Electronics Engineers (IEEE). - 2156-342X .- 2156-3446. ; 4:1, s. 56-64
-
Tidskriftsartikel (refereegranskat)abstract
- Design and characterization of InP DHBT amplifiers in common-emitter and common-base topologies are presented. Both one-stage and multistage circuits are demonstrated. For one of the amplifiers, a peak gain of 24 dB at 255 GHz is measured, which is among the highest reported gains for HBT amplifiers above 200 GHz, and more than 10 dB gain at 210-315 GHz. The noise figure of this amplifier is measured on-wafer at 240-295 GHz, and it demonstrates a minimum noise figure of 10.4 dB at 265 GHz, which is the lowest reported noise figure for HBT amplifiers above 200 GHz.
|
|
| 4. |
- Eriksson, Klas, 1983, et al.
(författare)
-
H-band MMIC amplifiers in 250 nm InP DHBT
- 2012
-
Ingår i: 19th International Conference on Microwaves, Radar and Wireless Communications, MIKON 2012, Warsaw, 21-23 May 2012. - 9781457714351 ; 2, s. 744-747
-
Konferensbidrag (refereegranskat)abstract
- In this paper, single-stage and multistage amplifiers of two different topologies, common-base with resistive feedback and common-emitter, operating at up to 290 GHz are presented and demonstrated. The amplifiers use an indium-phosphide (InP) double-heterojunction bipolar transistor (DHBT) process. The multistage common-emitter amplifier demonstrates a gain above 10 dB from 220 to 280 GHz with a peak gain of 15 dB while the multistage common-base amplifier demonstrates a gain of 16 dB at 265 GHz.
|
|
| 5. |
- Karandikar, Yogesh, 1982, et al.
(författare)
-
A compact 340 GHz 2x4 patch array with integrated subharmonic gilber core mixer as a building block for multi-pixel imaging frontends
- 2014
-
Ingår i: Technical Digest - IEEE Compound Semiconductor Integrated Circuit Symposium, CSIC. - 1550-8781. - 9781479936229
-
Konferensbidrag (refereegranskat)abstract
- For linear multi-pixel imaging systems, a linear stack of pixels comprising of an antenna and a heterodyne receiver are needed. Such pixels can be realized using MMIC processes. The main constraint for such multi-pixel system is a compact array of pixels giving high coupling to quasi-optics used for focusing. This paper addresses this trade-off and presents a novel solution based on beam synthesis of two consecutive subarrays. One such sub-array along with heterodyne receiver is described as half-pixel in this paper and it is realized using 2x4 patch array and Gilbert core sub-harmonic mixer using a 250nm DHBT process. The patch array has ohmic loss better than 8 dB and mixer conversion loss is 6-8 dB over 320-350 GHz RF band. The chip size is 1mm x 2mm and therefore for 7 simultaneous beams a MMIC of 8 half-pixels is foreseen.
|
|
| 6. |
- Karandikar, Yogesh, 1982, et al.
(författare)
-
Compact integration of sub-harmonic resistive mixer with differential double slot antenna in G-band using 50nm InP-HEMT MMIC process
- 2012
-
Ingår i: 2012 IEEE Compound Semiconductor Integrated Circuit Symposium, CSICS 2012, La Jolla, CA, 14 - 17 October 2012. - 1550-8781. - 9781467309295
-
Konferensbidrag (refereegranskat)abstract
- Sub-Harmonic resistive HEMT based mixers in Gband have been designed and integrated with Double Slot Antenna in Differential Configuration for the first time. This novel topology shows compact integration of active devices between antenna ports while achieving 25 GHz bandwidth around 200 GHz. The dual-gate 50nm x 15um InP HEMT used in the design achieves the conversion loss of 15 dB with +3 dBm LO power drive. Furthermore, a similar topology when used as a Harmonic mixer using a single gate device offers 16.5 dB conversion loss for +4 dBm LO power. For compact integration, via hole matching on slot antenna is also presented.
|
|
| 7. |
|
|
| 8. |
- Lai, Szhau, 1985, et al.
(författare)
-
A varactor model including valanche noise source for VCOs phase noise simulation
- 2011
-
Ingår i: 41th European Microwave Conference , Manchester, UK, Oct 10-13, 2011. - 9781612842356 ; , s. 591-594
-
Konferensbidrag (refereegranskat)abstract
- Abstract — This work studies an important area of oscillatoroperation – VCO biased at varactor breakdown. In this operation, the oscillator’s phase noise is primarily determined by avalanche noise generated in the varactor, i.e., the phase noise can be modulated by the incremental shot noise generated at varactor breakdown. A simple experimental diode model was optimized for modeling varactor-breakdown current and an empirical shot noise model based on Hine’s theory presents good agreement with noise power measurements of varactors.The developed varactor noise-model has successfully been used to simulate the phase noise of a single-ended Colpitts InGaP HBT VCO over and beyond the varactor’s breakdown voltage. The VCO presents a phase noise below -100dBc/Hz for varactor voltages lower than breakdown voltage. Beyond the breakdown the phase noise gradually increases to -60 dBc/Hz@100kHz with a centre frequency deviating less than 0.6% from a 7.38GHz carrier.
|
|
| 9. |
- Rahiminejad, Sofia, 1987, et al.
(författare)
-
Design of micromachined ridge gap waveguides for millimeter-wave applications
- 2011
-
Ingår i: Procedia Eng.. - : Elsevier BV. ; 25, s. 519-522
-
Konferensbidrag (refereegranskat)abstract
- The ridge gap waveguide is a new transmission line for millimeter-wave applications. Traditionally, rectangular waveguides are used for those applications due to their low loss. However their fabrication requires precision machining, very good electrical contact and alignment between two joining mechanical parts. Ridge gap waveguides can obtain similar performance without requiring conductive sidewalls and this provides more freedom during the fabrication and assembly process as the structure is no longer sensitive to small gaps between the side walls and the upper lid. The ridge gap waveguide has already been validated for 10-20 GHz using conventional fabrication methods. The ridge gap waveguide prototypes presented in this paper are designed to work in the frequency region between 210 and 340 GHz, and fabricated using MEMS technology. MEMS technology provides fabrication precision of the structures and thus opens the path for high-frequency components.
|
|
| 10. |
|
|
