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101.
周芸 《舰船电子对抗》2011,34(6):106-109
提出了将VxWorks操作系统及其图形用户接口工具Zinc引入到雷达显控终端软件设计中的必要性,通过实例介绍了Zinc的界面设计流程,给出了某雷达显控终端软件的设计架构,着重分析了Zinc在终端软件设计中几个关键的实现技术,具有很强的实用性。  相似文献   
102.
A sampled-grating distributed Bragg reflector laser module having an integrated multiwavelength locker has been developed and evaluated. The uniquely designed wavelength locker made of thermally controlled etalon has provided uniform wavelength monitoring and very stable wavelength locking in the 188-ITU grid channels (37 nm) with 25-GHz spacing. Over the case temperature from -5/spl deg/C to 65/spl deg/C, the laser wavelength was locked within /spl plusmn/0.5 GHz, and the total power consumption of the module was less than 4 W.  相似文献   
103.
为了克服基于身份的数字签名所固有的问题,同时解决签名在一些特殊环境中产生的效率问题,利用双线性对的技术,结合自认证签名和聚合签名的概念,提出了一个自认证聚合签名方案,该方案合并了自认证签名和聚合签名的优势。最后在随机预言模型下给出了方案的安全性证明。  相似文献   
104.
The Enhanced Distributed Channel Access (EDCA) has been proposed as the mandatory channel access method in IEEE 802.11e to provide Quality-of-Service enhancement. Transmission Opportunity (TXOP) is adopted in the EDCA as one of the service differentiation mechanisms. With the TXOP mechanism, nodes in each Access Category (AC) are allowed to transmit multiple packets for different time intervals after gaining the channel access. Throughput differentiation can then be realized among ACs. The effect of the TXOP mechanism on the performance differentiation was widely studied in previous work. Despite these efforts, it remains largely unknown how the TXOP mechanism affects the optimal network performance. This paper is devoted to study how to achieve the maximum network throughput with the service differentiation requirement via the TXOP mechanism in a saturated IEEE 802.11e EDCA network. In particular, the expressions of both the node throughput and the network throughput are derived as functions of system parameters including the TXOP value in each AC. The node-throughput ratio is determined by TXOP values, which validates that the TXOP mechanism is effective in providing throughput differentiation. The explicit expression of the maximum throughput is further derived, and is found to be determined by the TXOP mechanism and the service differentiation requirement of each AC. To achieve the maximum throughput, the initial backoff window size of each AC should be adaptively chosen according to the TXOP values, the targeted node-throughput ratios as well as the number of nodes in each AC.  相似文献   
105.
Motivated by the center weighted Hadamard matrix, we propose an improved algorithm for the fast fractional jacket transform (FRJT) based on eigendecomposition of the fractional jacket matrix (FRJM). Employing a matrix diagonalization transformation that decomposes a matrix of large size into products of the matrices composed of eigenvectors and eigenvalues, an FRJM of large size can be fast factored into products of several sparse matrices in a recursive fashion. To generate an FRJM of large size, an algorithm for the factorable FRJM can be conveniently designated with a reduced computational complexity in terms of additions and multiplications. Since the proposed FRJM itself concerns interpretation as a suitable rotation in the time-frequency domain, it is applicable for optics and signal processing.  相似文献   
106.
A new type of abnormal drain current (ADC) effect in fully depleted (FD) silicon-on-insulator (SOI) MOSFETs is reported. It is found that the drain current becomes abnormally large for specific front- and back-gate voltages. The drain current exhibits a transient effect due to the floating body behavior and no longer follows the conventional interface coupling theory for these specific front- and back-gate bias conditions. It is shown that the ADC can be generated by the combination of gate-induced drain leakage, transient effects, and parasitic bipolar transistor action in FD SOI MOSFETs.  相似文献   
107.
空间用紫外探测及AlGaN探测器的研究进展   总被引:1,自引:3,他引:1  
文中介绍了与空间应用有关的紫外探测。首先,介绍了美、欧等西方国家在空间天文以及行星、卫星探测等方面多年来的紫外应用情况,包括卫星探测器上搭载的紫外有效载荷;然后,评述了目前在空间使用的紫外探测器状况,以及在未来的空间应用中极具发展潜力的AlGaN紫外探测器;最后,对AlGaN紫外焦平面探测器国内外近年来的研究进展进行了阐述。  相似文献   
108.
A Highly Parallel Joint VLSI Architecture for Transforms in H.264/AVC   总被引:1,自引:0,他引:1  
In H.264/AVC, the concept of adapting the transform size to the block size of motion-compensated prediction residue has proven to be an important coding tool. This paper presents highly parallel joint circuit architecture for 8 × 8 and 4 × 4 adaptive block-size transforms in H.264/AVC. By decomposing the 8 × 8 transform to basic 4 × 4 transforms, a unified architecture is designed for both 8 × 8 and 4 × 4 transform and the transform data-path can be efficiently reused for six kinds of transforms. i.e., 8 × 8 forward, 8 × 8 inverse, 4 × 4 forward, 4 × 4 inverse, forward-Hadamard, inverse-Hadamard transforms. Linear shift mapping is applied on the memory buffer to support parallel access both in row and column directions which eliminates the need for a transpose circuit. For reusable and configurable transform data-path, a multiple-stage pipeline is designed to reduce the critical path length and increase throughput. The design is implemented under UMC 0.18 um technology at 200 MHz with 13.651 K logic gates, which can support 1,920 × 1,088 30 fps H.264/AVC HDTV decoder.
Yu LiEmail:
  相似文献   
109.
Flexible organic thin-film transistors (OTFT) were fabricated on 304 and 430 stainless steel (SS) substrate with aluminum oxide as a gate insulator and pentacene as an organic semiconductor. Chemical mechanical polishing (CMP) process was used to study the effect of the SS roughens on the dielectric properties of the gate insulator and OTFT characteristics. The surface roughness was decreased from 33.8 nm for 304 SS and 19.5 nm for 430 SS down to ~2.5 nm. The leakage current of the metal–insulator–metal (MIM) structure (Au/Al2O3/SS) was reduced with polishing. Mobility and on/off ratio of pentacene TFT with bare SS showed a wide range of values between 0.005 and 0.36 cm2/Vs and between 103 and 105 depending on the location in the substrate. Pentacene TFTs on polished SS showed an improved performance with a mobility of 0.24–0.42 cm2/Vs regardless of the location in the substrate and on/off ratio of ~105. With self assembled monolayer formation of octadecyltrichlorosilane (OTS) on insulator surface, mobility and on/off ratio of pentacene TFT on polished SS was improved up to 0.85cm2/Vs and ~106. IV characteristics of pentacene TFT with OTS treated Al2O3/304 SS was also obtained in the bent state with a bending diameter (D) of 24, 45 or 70 mm and it was confirmed that the device performed well both in the linear regime and the saturation regime.  相似文献   
110.
In this paper, we propose and analyze the integration of source and jammer for a decode-and-forward two-way scheme under physical layer security where the source nodes not only transmit data signals, but also transmit jamming signals to degrade the quality of eavesdropping links, and a selected relay forwards the combined data signals using an XOR operation. In this proposed protocol, the best relay is chosen by the maximum end-to-end achievable secrecy rate, and the secrecy system performance is evaluated by the exact and asymptotic secrecy outage probability over flat and block Rayleigh fading channels. The Monte-Carlo results are presented to verify the theoretical analysis.  相似文献   
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