Estimation of Transmitted Power Density from Temperature Experiment for EMF Exposure Assessment at 60 GHz

Author(s):  
Kun Li ◽  
Kengo Kawabata ◽  
Kensuke Sasaki ◽  
Ryosuke Suga ◽  
Soichi Watanabe ◽  
...  
1992 ◽  
Vol 281 ◽  
Author(s):  
Pin Ho ◽  
M. Y. Kao ◽  
P. C. Chao ◽  
K. H. G. Duh ◽  
P. M. Smith ◽  
...  

ABSTRACTHigh electron mobility transistors (HEMTs) based on the InAlAs/InGaAs heterostructure have been grown on InP by molecular beam epitaxy. At room temperature, typical sheet charge densities of 2.1–3.0×1012 cm−2 and Hall electron mobilities over 10000 cm2 /V-s are obtained. An electron mobility as high as 13000 cm2 /V-s is achieved with a pseudomorphic Iny Ga1−y As channel and a y value of 0.70.HEMTs with a T- or Γ-shaped gate and with gate lengths ranging from 0.1–0.25 urn have been fabricated. A record low noise figure of 0.7 dB with an associated gain of 8.6 dB at 62 GHz has been achieved with 0.1 μm Γ-gate devices, while T-gate devices exhibit a minimum noise figure of 1.2 dB with 7.2 dB associated gain at 94 GHz. Separately, a record fmax value of 455 GHz was determined by extrapolating at -6 dB/octave from the measured gain of 13.6 dB at 95 GHz.Power HEMTs using a double heterojunction structure exhibit a record peak power-added efficiency (P.A.E.) of 49% with 8.6 dB power gain and 0.30 W/mm power density measured at 60 GHz. When biased and tuned for maximum output power, our best 60 GHz output power density to date is 0.52 W/mm with 33% P.A.E. and 5.9 dB power gain using a single heterojunction HEMT scheme with pseudomorphic channel. A similar device also yields peak P.A.E. of 26% with 0.20 W/mm power density and 4.9 dB gain at 94 GHz. These results represent the highest P.A.E.S and power gains ever reported for any transistor at these frequencies.


2018 ◽  
Vol 41 (4) ◽  
pp. 985-991 ◽  
Author(s):  
Chhavi Raj Bhatt ◽  
Mary Redmayne ◽  
Michael J. Abramson ◽  
Malcolm R. Sim ◽  
Christopher Brzozek ◽  
...  

2014 ◽  
Vol 13 ◽  
pp. 1693-1696 ◽  
Author(s):  
Artem V. Boriskin ◽  
Maxim Zhadobov ◽  
Yves Le Drean ◽  
Ronan Sauleau

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Giulia Sacco ◽  
Stefano Pisa ◽  
Maxim Zhadobov

AbstractWith the development of 5th generation (5G) mobile networks people of different ages will be exposed in the upper part of the microwave spectrum. From the perspective of non-ionizing radiation dosimetry, an accurate analysis of age-dependent electromagnetic power deposition and resulting heating is required. In this study, we evaluate the effect of age on exposure at 26 GHz and 60 GHz. A near-surface tissue model illuminated by a plane wave is used to asses the exposure considering both frequency-independent and frequency-dependent limits. The age-related variation of the skin thickness and tissue electromagnetic properties has been considered. Moreover, the blood flow decrease rate has been taken into account to assess the age-dependent heating. Our results demonstrate that the overall variations of the power density, specific absorption rate (SAR) and heating in the near-surface tissues are limited to about 10–15%. These variations are mainly due to the tissue permittivity and blood flow change with age. In contrast to the transmitted power density that increases with age, the peak SAR decreases at both frequencies. The peak steady-state heating increases from 5 to 70 years old by roughly 11% at 26 GHz and 13% at 60 GHz.


2018 ◽  
Vol 39 (8) ◽  
pp. 617-630 ◽  
Author(s):  
Esra Neufeld ◽  
Eduardo Carrasco ◽  
Manuel Murbach ◽  
Quirino Balzano ◽  
Andreas Christ ◽  
...  

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