Browsing by Author "Chen, GH"

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A simulation study of a distributed antenna-based CDMA system
(1996)
Chen, GH
;
Yu, CM
;
Huang, CC
;
交大名義發表
;
電信工程研究所
In this paper, a computer simulation study on both coverage and capacity performance of a distributed antenna based CDMA system is presented. Wideband direct sequence spread spectrum signalling with a perfect RAKE receiver is assumed. Computer simulations are used to evaluate the distribution of received signal strength in a single cell architecture, and the distribution of received signal's SIR in a cellular architecture, for both a central antenna based system and a distributed antenna based system. It is found from our simulation that a distributed antenna based system has the potential to provide larger coverage area and higher capacity as compared with a central antenna based system.
Characteristics of polycrystalline silicon thin-film transistors with electrical source/drain extensions induced by a bottom sub-gate
(2002-05-01)
Yu, M
;
Lin, HC
;
Chen, GH
;
Huang, TY
;
Lei, TF
Characteristics of polycrystalline silicon thin-film transistors (TFT) with source/drain extensions induced by a bottom sub-gate were explored, high on/off current ratio up to 10(7) could be achieved for both n- and p-channel devices. Nevertheless, the performance is significantly degraded by a marked increase of off-state leak-age current when the channel length is scaled below 1 mum. Moreover, a hump in the subthreshold current-voltage regime is observed. After careful analysis, it is found that the leakage current is strongly dependent on the field strength and is not a thermally activated process. A leakage path along the bottom interface of the poly-Si channel layer is proposed to explain these results.