cognitive radio the technologies required
Báo cáo toán học: " Decision making for cognitive radio equipment: analysis of the first 10 years of exploration" potx
... dimensions On the other hand, the actual design space is included in the virtual design space It results from the reduction of the design space when taking into account the correlation between the different ... within the CR framework, we can define the a priori knowledge as the set of theoretical or practical assumptions provided by the designer to the CR decision making engine These assumptions, if they ... are then processed by the decision making engine The kind of process highly depends on the quality of the metrics (level of uncertainty on the captured numerical value for instance) as well as the...
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Báo cáo hóa học: " Research Article Modeling the Lion Attack in Cognitive Radio Networks" pptx
... (21), is the average inactivity time of the TCP source due to the attack derived in the previous section The average activity time A is the mean time since the end of a frequency handoff until the ... handoffs on the throughput, also the bit error rate (BER) The attacker must sense the medium in order to detect the next channel to be used by the CRN after the handoff Assuming 45% of the TV channels ... improve the attack The fact is that freezing TCP parameters limits the attacker to only degrade the TCP throughput, since there are no transmissions during the handoff time However, if the attacker...
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Báo cáo hóa học: "Decision making for cognitive radio equipment: analysis of the first 10 years of exploration" potx
... dimensions On the other hand, the actual design space is included in the virtual design space It results from the reduction of the design space when taking into account the correlation between the different ... within the CR framework, we can define the a priori knowledge as the set of theoretical or practical assumptions provided by the designer to the CR decision making engine These assumptions, if they ... are then processed by the decision making engine The kind of process highly depends on the quality of the metrics (level of uncertainty on the captured numerical value for instance) as well as the...
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D The technologies
... Appendix D The Technologies Methods The method used for the request message is indicated in the status line of the request The server uses the method to determine the purpose of the request The HTTP ... how the messages are sent between the client and the server Client Request The request is built from three parts: the status line, the header, and optionally the body The client initiates the ... with the HTTP server by sending the request These are the steps in sending the request: Resolve the server name to an IP address Establish a connection to the server address using port 80 Send the...
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Tài liệu COGNITIVE RADIO ARCHITECTURE pptx
... COGNITIVE RADIO ARCHITECTURE The Engineering Foundations of Radio XML JOSEPH MITOLA III A JOHN WILEY & SONS, INC., PUBLICATION COGNITIVE RADIO ARCHITECTURE COGNITIVE RADIO ARCHITECTURE The ... ontology of the ideal cognitive radio, the iCR.) CR is based on “software radio. ” (See J Mitola, Software Radio Architecture, Wiley, Hoboken, NJ, 2000) Between 1998 and 2000, I refi ned cognitive radio ... aware and adaptive radios toward cognitive radio, the AACR revolution AACR technology can also power increasingly autonomous cognitive wireless networks (CWNs) The cognitive radio architecture...
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Báo cáo khoa học: Definition of the residues required for the interaction between glycine-extended gastrin and transferrin in vitro pptx
... of the wild-type value [18] The biochemical basis of the gastrin–transferrin interaction is still unknown Knowledge of the regions of transferrin required for the binding of gastrin, and of the ... ApoTf into the BIAcore channel to determine whether the ferric ions were required for the interaction between gastrins and ApoTf In the presence of EDTA, no interaction between ApoTf and either Gamide ... both the formation and stability of the gastrin–ApoTf complex (A) Injection of the iron chelator ETDA (3 mM) into the BIAcore channel at the same time as ApoTf prevented the association between the...
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Advances in Cognitive Radio Systems pptx
... use the same values for the lumped elements both in the drain an in the gate line Frequency dependent part only accounts for the impedance of the constant k- sections 8 Advances in Cognitive Radio ... for Cognitive Radio Systems 11 balance via the KCL is then established between the two subsets in the form of nonlinear algebraic system of equations involving the unknown coefficients of the ... circulating in the feedback loop, are re-inserted in the input line through the output node The feedback path length determines the operating frequency; as the path length gets smaller, the maximum...
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cognitive radio technology 2nd ed - b. fette (ap, 2009)
... the cognitive radio can adapt for: the spectrum regulator the network operator ■ the user objectives ■ ■ The first of these, the spectrum regulator, has generally allocated all the spectrum there ... Reflection in a Cognitive Radio Cognitive radios need to be able to tell other CRs what they are observing that may affect the performance of the radio communication channel The receiver can ... of Cognitive Radio Technology radio, allowing the radio to provide network services and to be remotely controlled over the local Ethernet Some radios will also provide for control of external radio...
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Báo cáo sinh học: "Fair, efficient, and power-optimized spectrum sharing scheme for cognitive radio networks" pot
... participates in the sharing decision They exchange the information about the sensed spectrum and then collectively share the spectrum among them according to their requirement Another classification ... schedules the sensed spectrum holes among cognitive radio (CR) users by considering the changes occur in the radio environment as well as the PU’s activity on current in use channels In the proposed ... at the start of each slot The CR monitors the in-use channel for PU activity If the channel is still idle, it will perform the transmission on the same channel otherwise it looks for some other...
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Báo cáo toán học: " Spectrum sensing for cognitive radio exploiting spectrum discontinuities detection" potx
... the changing noise level and the interference level Another challenging issue is that the energy detection approach cannot distinguish the PU from the other SU sharing the same channel CFD is more ... only at the edges of the K bands (4) The corrupting noise is additive white and zero mean The input signal is the amplitude spectrum of the received noisy signal We assume that its mathematical ... simplicity, the comparison is made with reference to it Denoting M the number of samples of the received signal yn and N is the model order of the AD, we show that the AD complexity is N M and the ED...
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Báo cáo toán học: " Optimization of cooperative spectrum sensing with sensing user selection in cognitive radio networks" potx
... number of cooperative SUs rather than selecting all the SUs within the CRN The rest of the article is organized as follows: The system model is introduced in Section The problem formulation based ... article For the AWGN environment, all the SUs have the same channel coefficient hi due to all the SUs having identical path loss Therefore, the instantaneous detection SNRs of all SUs are the same ... represents the received signal at the ith SU h i denotes the channel coefficient from the PU to the ith SU, which is assumed to be constant during the sensing phase [13] si(n) is the signal transmitted...
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Báo cáo hóa học: " Performance analysis of spectrum sharing mechanisms in cognitive radio networks" pptx
... released before the PU’s waiting time is due, then the PU can access the target channel and the PU’s service is only deferred Otherwise, the PU will be blocked Once the SUs sense that there appears ... and inform the secondary system the target channel that it reclaims The SU in the specific channel will vacate the channel immediately after it finishes the ongoing transmission If the channel ... between the primary and the secondary systems [11] A contract between the primary and the secondary systems has to be made in spectrum broker The interactions between the primary and the secondary...
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Báo cáo hóa học: " Multistage Quadrature Sigma-Delta Modulators for Reconfigurable Multi-Band Analog-Digital Interface in Cognitive Radio Devices" pot
... (feeding the input to the loop filters) can be used to tune the STF zeros independent of the NTF The NTF zeros are usually placed on the desired signal band(s) to create the noise-shaping effect At the ... Figure The possible number of these notches is defined by the overall order of the modulator With multistage QΣΔM this is the combined order of all the stages In addition, the frequencies of the ... overall IRR of the complete multistage structure, the transfer functions of the original signals (the input and the errors) and their conjugate In addition to the above IRRs, the performance...
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Báo cáo hóa học: "Location based spectrum sensing evaluation in cognitive radio networks" pptx
... investigating the relationship between the overall average probability of detection and the threshold We also study the impact of the CR network scale on the probability of detection and the outage at the ... if the measured energy is less than a proper threshold Therefore, the spectrum sensing problem may be modeled as a binary hypothesis problem: H0: The PU is absent, H1: The PU is present Furthermore, ... aggregation caused by the SUs The interference suffering by the PU is mainly caused by the SU’s behavior of missed detection of the PU’s signals For facilitating the following discussion, the overall average...
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Báo cáo hóa học: " Power allocation, bit loading and sub-carrier bandwidth sizing for OFDM-based cognitive radio" pot
... that there are K SU transceivers, and the PU is in the radio range of all of them (Figure 3) The assumptions on the propagation channel are the same as in the single user case (Sect III) The multi-user ... interference from the PU on the ith SU subcarrier J i depends on the power spectral density (PSD) of the PU and the channel gain between the PU Tx and SU Rx The interference from the SU on the jth PU ... [10] On the other hand, the users are allocated sub-carriers based on the channel-tonoise ratio (CNR), and the Lagrangian formulation is used to maximize the sum capacity of the SUs under the PU...
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báo cáo hóa học: " ZAP: a distributed channel assignment algorithm for cognitive radio networks" pot
... of the prolonged absence of these stimuli By identifying the received stimulus, state causes the execution flow to deviate to any of the other states and, therefore, is called the Scheduler The ... assume that the channel list is sorted from the worst to the best channel, so that the best channel has the highest index As the next step, the channel ch is assigned to link in the list AssignedList ... of the factors limiting the performance of the network is the interference– i.e., two nodes cannot perform successful communication if they are using the same channel at the same time and if they...
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Báo cáo hóa học: " Selective sensing and transmission for multi-channel cognitive radio networks" doc
... channel, the probability of collision (interference) will increase; otherwise, SU’s channel utilization will decrease Therefore, the rapidly the channel’s ON/OFF state varies, the frequently the channel ... model According to the definition of SS-SA strategy, SU senses the only channel at the beginning of each slot and then access the whole slot if and only if the sensing result is OFF The optimal slot ... channel and the channel utilization will degrade Furthermore, in theory, the maximal sensing period for PS-SA strategy is i Tc Ts = = 46.4 (ms) Therefore, the simulation N Figure The channel...
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Báo cáo hóa học: " Research Article Channel Sensing without Quiet Period for Cognitive Radio Systems: A Pilot Cancellation Approach" ppt
... rm,l (5) Then, the resulting test statistic is compared to the threshold value, If Δ > , the CR user decides that the PU exists Otherwise, the CR user regards the spectrum band as empty There can ... called the “false alarm” and the “missdetection.” The false even though the PU is not alarm is issued when Δ > activated; the missdetection is the case that Δ < when the PU exists actually These ... that the PU with stronger signal can be more easily detected by the CR user Figure also shows that the simulated and the theoretical results well match with each other This indicates that the theoretical...
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Báo cáo hóa học: " Review Article Comparison among Cognitive Radio Architectures for Spectrum Sensing" pdf
... reduced to simply collect the decision of the CR terminals On the contrary, if the CR terminals perform only the sampling of the signals, all the other functions are delegated to the data fusion center: ... decision In such case, the CR terminals perform all the steps of the processing chain, from the sampling to the classification phase, and they transmit to the fusion center only the classification results ... through the control channel, the distribution of the processing capabilities between the data fusion center and the other terminals, and the number of terminals have to be considered in the analysis...
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Tìm thêm: xác định các mục tiêu của chương trình xác định các nguyên tắc biên soạn khảo sát các chuẩn giảng dạy tiếng nhật từ góc độ lí thuyết và thực tiễn khảo sát chương trình đào tạo của các đơn vị đào tạo tại nhật bản khảo sát chương trình đào tạo gắn với các giáo trình cụ thể xác định thời lượng học về mặt lí thuyết và thực tế điều tra đối với đối tượng giảng viên và đối tượng quản lí điều tra với đối tượng sinh viên học tiếng nhật không chuyên ngữ1 khảo sát các chương trình đào tạo theo những bộ giáo trình tiêu biểu nội dung cụ thể cho từng kĩ năng ở từng cấp độ xác định mức độ đáp ứng về văn hoá và chuyên môn trong ct phát huy những thành tựu công nghệ mới nhất được áp dụng vào công tác dạy và học ngoại ngữ mở máy động cơ lồng sóc các đặc tính của động cơ điện không đồng bộ đặc tuyến tốc độ rôto n fi p2 đặc tuyến dòng điện stato i1 fi p2 động cơ điện không đồng bộ một pha sự cần thiết phải đầu tư xây dựng nhà máy chỉ tiêu chất lượng theo chất lượng phẩm chất sản phẩm khô từ gạo của bộ y tế năm 2008 chỉ tiêu chất lượng 9 tr 25