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581.
掩模版图设计是实现集成电路制造的重要环节。版图设计常用的工具是Cadence公司的Virtuoso Layout Editor。本文介绍的Turbo Toolbox,可内嵌于Virtuoso Layout Editor中,集总版图工具,简化命令序列,实现更复杂,更具设计化的操作,大大提高版图工作效率。 相似文献
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Emerging evidence indicates that orthogonal time–frequency space (OTFS) modulation is a potential candidate modulation scheme for high mobility wireless communications. However, OTFS may experience significant inter-symbol interference (ISI) and inter-Doppler interference (IDI) in the receiver. In this paper, we propose a soft decision feedback turbo equalization for OTFS transmission over delay-Doppler channels to jointly combat both interferences. A novel block decision feedback equalization (BDFE) algorithm is constructed using the band feature of the channels in the delay-Doppler domain. The feedforward and feedback filters are designed by the delay-time channels coefficients. According to the designed filter, an equivalent system model is employed to allow turbo equalization. The posterior probability is established using the soft prior information and feedback filter, and then fed back to the channel decoder as external information. Both theoretical analysis and simulation results demonstrate the effectiveness of the proposed scheme in improving the bit error rate (BER) performance and combat various interference. Numerical simulations are finally provided to justify the validity of the proposed scheme in improving the bit error rate (BER) performance and combating various interference. 相似文献
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He Chun Hu Jianhao 《电子科学学刊(英文版)》2008,25(2):145-149
A novel memory efficient path metric update is proposed for Maximum A Posteriori (MAP) decoder of turbo codes to reduce the memory requirement of state metric information calculation. For MAP decoder, the same memory can be shared by the forward and backward metrics with this metric update scheme. The forward and backward metrics update can be performed at the same time. And all of the extrinsic information can be calculated at the end of metric update. Therefore, the latency and area in the implementation will be reduced with the proposed metric update method. 相似文献
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Xiaolin Yu Dr. Alexey A. Ryadun Dmitry I. Pavlov Dr. Tatiana Y. Guselnikova Dr. Andrei S. Potapov Vladimir P. Fedin 《Angewandte Chemie (International ed. in English)》2023,62(35):e202306680
Solvothermal reaction of 5,5′-(pyridine-2,6-diylbis(oxy))diisophthalic acid (H4L) with europium(III) or terbium(III) nitrates in acetonitrile-water (1 : 1) at 120 °C gave rise to isostructural 2D coordination polymers, [Ln(HL)(H2O)3]∞ ( NIIC-1-Eu and NIIC-1-Tb ), the layers of which are composed by eight-coordinated lanthanide(III) ions interconnected by triply deprotonated ligands HL3−. The layers are packed in the crystal without any specific intermolecular interactions between them, allowing the facile preparation of stable water suspensions, in which NIIC-1-Tb exhibited top-performing sensing properties through luminescence quenching effect with exceptionally low detection limits towards Fe3+ (LOD 8.62 nM), ofloxacin (OFX) antibiotic (LOD 3.91 nM) and cotton phytotoxicant gossypol (LOD 2.27 nM). In addition to low detection limit and high selectivity, NIIC-1-Tb features fast sensing response (within 60–90 seconds), making it superior to other MOF-based sensors for metal cations and organic toxicants. The photoluminescence quantum yield of NIIC-1-Tb was 93 %, one of the highest among lanthanide MOFs. Mixed-metal coordination polymers NIIC-1-EuxTb1−x demonstrated efficient photoluminescence, the color of which could be modulated by the excitation wavelength and time delay for emission monitoring (within 1 millisecond). Furthermore, an original 2D QR-coding scheme was designed for anti-counterfeiting labeling of goods based on unique and tunable emission spectra of NIIC-1-Ln coordination polymers. 相似文献
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