No abstract

No abstract

Electrostatic comb drive micro-mirror has limitation of high operation voltage, which has limited its practice use. Recent developments in decreasing operation voltage are promising for mobile micro-mirror. Especially, the operation voltage is decreased substantially by removing the air friction of comb-drive micro-mirror at a high resonant frequency when the mirror is operated at low pressure. Removing simultaneously the air friction and anchor loss, electrostatic comb-drive micro-mirror operating at a few voltages at a high resonant frequency becomes possible. This paper presents our recent developments as well as emerging techniques introduced in literature for decreasing the operation voltage of electrostatic comb drive micro-mirror. Methods for decreasing the operation voltage at large rotation angle and high scan frequency for application in the laser scanning display are focused to discuss in this paper.

<span>High-speed Terahertz communication systems has recently employed orthogonal frequency division multiplexing approach as it provides high spectral efficiency and avoids inter-symbol interference caused by dispersive channels. Such high-speed systems require extremely high-sampling <br /> time-interleaved analog-to-digital converters at the receiver. However, timing mismatch of time-interleaved analog-to-digital converters significantly causes system performance degradation. In this paper, to avoid such performance degradation induced by timing mismatch, we theoretically determine maximum tolerable mismatch levels for orthogonal frequency division multiplexing communication systems. To obtain these levels, we first propose an analytical method to derive the bit error rate formula for quadrature and pulse amplitude modulations in Rayleigh fading channels, assuming binary reflected gray code (BRGC) mapping. Further, from the derived bit error rate (BER) expressions, we reveal a threshold of timing mismatch level for which error floors produced by the mismatch will be smaller than a given BER. Simulation results demonstrate that if we preserve mismatch level smaller than 25% of this obtained threshold, the BER performance degradation is smaller than 0.5 dB as compared to the case without timing mismatch.</span>