| 1. |
- Ekelund, L, et al.
(author)
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Imaging of Four-Corner Fusion (SLAC Arthrodesis) of the Wrist with 64-Slice Computed Tomography.
- 2007
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In: Acta Radiologica. - : SAGE Publications. - 1600-0455 .- 0284-1851. ; 48:1, s. 76-79
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Journal article (peer-reviewed)abstract
- Purpose: To find out whether it is possible to evaluate the healing of wrist arthrodesis, carried out with a metallic spider plate, by means of 64-slice computed tomography (CT). Material and Methods: 18 CT examinations were performed in 12 patients 2 weeks to 37 months following scapholunate advanced collapse (SLAC) arthrodesis fixed with a metallic plate. Ten patients also had plain films of the wrist. Radiation doses were estimated. Results: Plain films were difficult to evaluate due to overprojection of the spider plate. With 64-slice CT, however, it was possible to evaluate the healing process in all patients in spite of metallic artifacts. Radiation doses were low. Conclusion: The healing of SLAC arthrodesis of the wrist is difficult to evaluate with conventional radiography due to the metallic plate. By means of 64-slice CT, however, it was possible to “see under” the plate in all 12 patients.
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| 2. |
- Horberg, Mikael, et al.
(author)
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A 110-170-GHz Non-Galvanic Interface for Integrating Silicon Micromachined Chips With Metallic Waveguide Systems
- 2021
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In: IEEE transactions on microwave theory and techniques. - : Institute of Electrical and Electronics Engineers (IEEE). - 0018-9480 .- 1557-9670. ; 69:8, s. 3667-3674
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Journal article (peer-reviewed)abstract
- We report on the development of a non-galvanic transition from a silicon micromachined to metallic rectangular waveguide for use in integrated waveguide systems at D-band (110-170 GHz). This transition overcomes the limitations of current solutions that require proper ohmic (galvanic) contact between both waveguides, and thus relaxes tolerance requirements in assembly and manufacturing. The transition uses an in-plane design which enables low-loss integration of micromachined waveguide components, as it eliminates the need for waveguide bends and complex multi-layer structures. We describe the RF design, analyze the EM simulation results, and explain the operating principle of the transition. To verify the concept, dedicated silicon micromachined and metallic waveguides are designed and fabricated. Characterization of the assembled samples shows good agreement with simulation. The transition achieves a typical insertion loss of 0.3 dB and return loss above 20 dB over most of the D-band. Measurement of multiple samples and repeated assemblies results in a variation of S21 of less than +/- 0.1 dB over the whole band, demonstrating good robustness and repeatability. By removing the need for galvanic connection, automated tools can then be used during system assembly, which enables industrial scale applications such as wireless communications.
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| 3. |
- Horberg, Mikael, et al.
(author)
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A 143 GHz InP-based radio link characterized in long-term outdoor measurement
- 2018
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In: 2018 ASIA-PACIFIC MICROWAVE CONFERENCE PROCEEDINGS (APMC). - 9784902339451 ; , s. 234-236
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Conference paper (peer-reviewed)abstract
- This paper reports on a 143 GHz radio link, evaluated in long-term outdoor measurements over a 200 m hop-length. The link has been characterized with a variable attenuator in a back-to-back configuration. For the outdoor tests the received power level and signal quality have been monitored for two months under various weather conditions. The radio link shows a highest throughput of 5.3 Gbps using 64 QAM and 1 GHz carrier bandwidth. The corresponding mean squared error of the demodulated signal is-25 dB, and the receiver sensitivity level is-42 dBm with 3 dB penalty compared to the theoretically calculated value for this setup. The long-term outdoor test is run at QPSK and 125 MHz carrier bandwidth.
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| 4. |
- Vassilev, Vessen, 1969, et al.
(author)
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Spectrum Efficient D-band Communication Link for Real-time Multi-gigabit Wireless Transmission
- 2018
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In: IEEE MTT-S International Microwave Symposium Digest. - 0149-645X. - 9781538650677 ; , s. 1523-1526
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Conference paper (peer-reviewed)abstract
- This manuscript presents results of wireless real-time data transmission at 143 GHz. The transmitter/receiver (Tx/Rx) front-end circuitry is integrated on a single monolithic microwave integrated circuits (MMICs), realized in a 250-nm indium phosphide (InP) double heterojunction bipolar transistor (DHBT) technology. The Tx module shows gain of 12 dB at 143 GHz with output power of -2.3 dBm at 1 dB gain compression. The Rx module has a gain of 15 dB with noise figure (NF) of 13 dB at 143 GHz. The minimum NF of 10 dB is measured at 132 GHz. The Tx/Rx front-end modules were integrated in two radio units to demonstrate a real time wireless data transmission. At a distance of 10 m and using 40 dBi gain antennas, the highest data rate achieved was 5.3 Gbit/s using 64 QAM modulation over a 1 GHz channel with spectrum efficiency of 5bit/s/Hz.
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