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101.
This paper proposes a distributed implementation of spatial modulation (SM) using cognitive radios. In distributed spatial modulation (DSM), multiple relays form a virtual antenna array and assist a source to transmit its information to a destination. The source broadcasts its signal, which is independently demodulated by all the relays. Each of the relays then divides the received data in two parts: the first part is used to decide which one of the relays will be active, and the other part decides what data it will transmit to the destination. An analytical expression for symbol error probability is derived for DSM in independent and identically distributed (i.i.d.) Rayleigh fading channels. The analytical results are later compared with Monte Carlo simulations. Further, an instantaneous symbol error rate (SER) based selection combining is proposed to incorporate the direct link between the source and destination with existing DSM. Next, DSM implementation is extended to a cognitive network scenario where the source, relays, and destination are all cognitive radios. A dynamic frequency allocation scheme is proposed to improve the performance of DSM in this scenario. The frequency allocation is modeled through a bipartite graph with end-to-end SER as a weight function. The optimal frequency allocation problem is formulated as minimum weight perfect matching problem and is solved using the Hungarian method. Finally, numerical results are provided to illustrate the efficacy of the proposed scheme. 相似文献
102.
Qasem Ramadan Lay Christophe William Teo Li ShuJun Feng Han Hua 《Analytica chimica acta》2010,673(1):101-3640
Simultaneous sample washing and concentration of two waterborne pathogen samples were demonstrated using a rotational magnetic system under continuous flow conditions. The rotation of periodically arranged small permanent magnets close to a fluidic channel carrying magnetic particle suspension allows the trapping and release of particles along the fluidic channel in a periodic manner. Each trapping and release event resembles one washing cycle.The performance of the magnetic separation system (MSS) was evaluated in order to test its functionality to isolate magnetic-labelled protozoan cells from filtered, concentrated tap water, secondary effluent water, and purified water. Experimental protocols described in US Environmental Protection Agency method 1623 which rely on the use of a magnetic particle concentrator, were applied to test and compare our continuous flow cell separation system to the standard magnetic bead-based isolation instruments. The recovery efficiencies for Giardia cysts using the magnetic tube holder and our magnetic separation system were 90.5% and 90.1%, respectively, from a tap water matrix and about 31% and 18.5%, respectively, from a spiked secondary effluent matrix. The recovery efficiencies for Cryptosporidium cells using the magnetic tube holder and our magnetic separation system were 90% and 83.3%, respectively, from a tap water matrix and about 38% and 36%, respectively, from a spiked secondary effluent matrix. Recoveries from all matrices with the continuous flow system were typically higher in glass tubing conduits than in molded plastic conduits. 相似文献
103.
通信开关电源的五种PWM反馈控制模式研究 总被引:6,自引:0,他引:6
根据实际设计工作经验及有关参考文献,比较详细地依据基本工作原理图说明了电压模式、峰值电流模式、平均电流模式、滞环电流模式、相加模式等PWM反馈控制模式的基本工作原理、发展过程、关键波形、性能特点及应用要点. 相似文献
104.
The power analysis attack on SM4 using the chosen-plaintext method was proposed by Wang et al in 2013 CIS.The fixed data was introduced in the method when attacking the round key.However,the attack process was complex.There were many problems in the process,such as more power traces,more numbers of the chosen-plaintext and acquisition power traces.The correlation between the fixed data and the round key were presented,which could be used to decode the round key.Based on the correlation,the improved chosen-plaintext power analysis attack against SM4 at the round-output was proposed.The proposed method attacked the fixed data by analyzing the power traces of the special plaintext.And the round key was derived based on the correlation.The results show that the proposed attack algorithm is effective.The proposed method not only improves the efficiency of the attack by reducing number of power traces,number of the chosen-plaintext and number of acquisition power traces,but also can be applied to a chosen-plaintext power analysis attack against SM4 at the shift operation. 相似文献
105.
106.
The SO(3) gauge extension of SM, which is proposed to present a successfulexplanation for the observed small masses of neutrino and the nearly tri-bimaximal neutrino mixing, predicted the vector-like SO(3) triplet Majorana neutrinos and SUL(2) double Higgs bosons. In this work we calculate branching ratios of the charged lepton flavor violating decays lIlJV (V=γ,Z) induced by these Majorana neutrinos and Higgs bosons. We find that under the model parameters constrained by experimental bounds on the decays Z→lIlJ, the branching ratio of decays lI→lJγ can be up to 10-10, which may be accessible at the future experiments. 相似文献
107.
介绍了SM协议及GPRS网络测试仪中SM协议监测模块的基本概念和功能。监测功能包括消息解析、核心参数提取、利用关键参数进行呼叫合成及对合成结果进行统计分析处理4个环节。其中消息的解析又包含消息数据详细解析与合成信息数据提取解析2个部分,故需要重点说明SM协议监测模块消息结构,并在此基础上研究SM协议的详细解码和基础解码、CDR合成技术、实时统计分析等。现场测试保证了数据的真实性和相关理论方法的有效可行性。 相似文献
108.
The SO(3) gauge extension of SM, which is proposed to present a successful explanation for the observed small masses of neutrino and the nearly tri-bimaximal neutrino mixing, predicted the vector-like SO(3) triplet Majorana neutrinos and SUL(2) double Higgs bosons. In this work we calculate branching ratios of the charged lepton flavor violating decays lIlJV (V = γ, Z) induced by these Majorana neutrinos and Higgs bosons. We find that under the model parameters constrained by experimental bounds on the decays Z →lIlJ, the branching ratio of decays lI→lJγ can be up to 10^-10, which may be accessible at the future experiments. 相似文献
109.
110.
Anirban Bhowal Rakhesh Singh Kshetrimayum 《International Journal of Communication Systems》2019,32(3)
The system performance of mobile‐to‐mobile (D2D) cooperative communication has been improved by utilizing spatial modulation (SM) in this paper. The proposed system employs decode and forward (DF) relaying technique along with physical layer network coding (PLNC); hence, it has been named as SM‐based decode and forward two‐way relay (DFTWR). It enables full‐duplex communication thereby enhancing the system efficiency. Information bits are exchanged between the two bidirectional nodes. For two bits of information exchange, the antenna index is conveyed by the least significant bit (LSB) of the data symbol while the most significant bit (MSB) carries the message. The system performance has been investigated by analyzing certain performance metrics like lower and upper bounds of outage probability and average data rate for N‐α‐μ cascaded fading channels. The change in the system performance by varying certain parameters like relative geometrical gain, fading coefficients, and number of cascaded components has also been put forth in this paper. 相似文献