multiple access techniques in computer networks ppt

... 1Wireless NetworksLecture Multiple Access Techniques Dr Ghalib A Shah Trang 3Last Lecture ReviewTrang 4Multiple Access Techniques Frequency Division Multiple Access Trang 5 FDMA was the initial multiple-access ... 15Random Acces s  ► more efficient way of managing medium acces s   for communicating s hort burs ty mes s ages • in contrast to fixed-access schemes, each user gains access to medium only when needed -has ... allotted time slots for a channel allowing sharing of a single channel  Each of the user takes turn in transmitting and receiving data in a Trang 8How it works? User presses Push-to-Talk (PTT)

Ngày tải lên: 05/07/2022, 13:06

... sort of combining al-gorithm In this study two different combining procedures are considered, namely, selective combining (SC) and maxi-mal ratio combining (MRC) 4.1 Selective combining Figure ... TTI value selective combining and increasing the number of received radio links provides reduction in the transmitted power in-dependently of the combining technique InFigure 8, for the reference ... channel P Spreading and scrambling Spreading and scrambling Pilot channel Enhancement information stream Channel coding (turbo code) Rate matching Physical channel segmentation Interleaver Interleaver

Ngày tải lên: 22/06/2014, 22:20

... power spent in the sensing state In fact, in our protocol, the time during which sensors are in a sens-ing state is high, so if in this state they spend the same en-ergy as in the receiving state ... ROUTING PROTOCOL—LEACH B+ We propose a new routing strategy which combines LEACH B [18] with a simple single-path routing protocol, which in-cludes the direct transmission to the final sink, ... point out that the random changing of the CHs can mitigate the hidden terminal problem In fact, in every round in LEACH B+ v1, or every two rounds in LEACH B+ v2, the clusters change according

Ngày tải lên: 23/06/2014, 00:20

... in such way that each signal can be received without interference from another CCU Wireless Access Tech Lab Wireless Access Tech Lab Introduction (2) CCU Wireless Access Tech Lab Wireless Access ... communication CCU Wireless Access Tech Lab Wireless Access Tech Lab Introduction (4) CCU Wireless Access Tech Lab Wireless Access Tech Lab Frequency Division Multiple Access (FDMA) (1) Each transmitter ...  Provides two distinct bands of frequencies for every user  Time Division Duplex (TDD)  Multiple users share a signal channel by taking turns in time domain  Each duplexing channel has both

Ngày tải lên: 11/07/2014, 21:20

... Trang 1IN CONSTRAINT NETWORKSZHANG YUANLIN NATIONAL UNIVERSITY OF SINGAPORE 2003 Trang 2IN CONSTRAINT NETWORKSZHANG YUANLIN

(BEng, EAST CHINA INSTITUTE OF TECHNOLOGY ( ... theconstraint processing in picture processing [Mon74] He found that certain binaryconstraint networks can be solved (or otherwise approximated) by introducing aclosure operation on constraints Mackworth ... Traditionally is studied in binary constraint networks In the last decade, alot of effort in CSP community has focused on non-binary networks as the CSPtechniques have been finding more and more applications

Ngày tải lên: 17/09/2015, 17:19

... Minimum Queueing DelayGPS Generalized Processor Sharing IETF Internet Engineering Task Force IntServ Integrated Services JoBS Joint Buffer Management and Scheduling LIRA Location Independent Resource ... relevantstate information in the packet header so that core routers do not need to maintain per-flow state information 172.3 The main components of the packet forwarding engine in the ProportionalDifferentiation ... backlogged service classes traversing a single link TheGMQD is a model that minimizes the total queueing delay of all backlogged serviceclasses traversing a single link Depending on traffic load conditions,

Ngày tải lên: 17/09/2015, 17:20

... Data Mining Data mining is the process of automatically discovering useful information in largedata repositories The three most popular data mining techniques are predictive mod-eling, clustering ... infrastructures These are able to produce globally meaningful information com-A Appice et al., Data Mining Techniques in Sensor Networks, 1 SpringerBriefs in Computer Science, DOI: 10.1007/978-1-4471-5454-9_1, ... change our lifestyle With the advances in their data miningability, these networks will play increasingly important roles in smart cities, bybeing integrated into smart houses, offices, and roads

Ngày tải lên: 23/10/2019, 16:13

... Data Mining Data mining is the process of automatically discovering useful information in largedata repositories The three most popular data mining techniques are predictive mod-eling, clustering ... infrastructures These are able to produce globally meaningful information com-A Appice et al., Data Mining Techniques in Sensor Networks, 1 SpringerBriefs in Computer Science, DOI: 10.1007/978-1-4471-5454-9_1, ... change our lifestyle With the advances in their data miningability, these networks will play increasingly important roles in smart cities, bybeing integrated into smart houses, offices, and roads

Ngày tải lên: 05/11/2019, 14:05

... from data A particulartask in machine learning can be defined by two sets: training and test sets corresponding to twostages At the first stage or training time, the training set is given to the ... improvingtraining and testing speed with nine times and 213 times faster than R-CNN at the trainingand testing stage, respectively The authors point out three significant drawbacks regarding itsmultiple ... learning, and do literature review for few-shot learning; ¥ Propose a learning techinque for training deep models (in computer vision) with popuplar datasets on the Internet; ¥ Apply few-learning

Ngày tải lên: 12/05/2022, 11:15

... from data A particulartask in machine learning can be defined by two sets: training and test sets corresponding to twostages At the first stage or training time, the training set is given to the ... improvingtraining and testing speed with nine times and 213 times faster than R-CNN at the trainingand testing stage, respectively The authors point out three significant drawbacks regarding itsmultiple ... learning, and do literature review for few-shot learning; • Propose a learning techinque for training deep models (in computer vision) with popuplar datasets on the Internet; • Apply few-learning

Ngày tải lên: 31/07/2024, 10:21

... Scheduling in Broadband Wireless Access Networks Rong Yu,1Yan Zhang,2and Shengli Xie1 1 School of Electronic and Information Engineering, South China University of Technology, Guangzhou 510641, China ... that the total cost is minimized Draining problem is indeed a simplified version of the original scheduling problem By assuming that there is no new packet arrival, draining problem is much more ... level, play key roles for resource sharing and QoS provisioning in BWA networks Different from traditional wired scheduling problems, packet scheduling in BWA networks will encounter two major difficulties:

Ngày tải lên: 21/06/2014, 23:20

... Layer Security in Non‑Orthogonal Multiple Access Networks Dinh‑Thuan Do 1,2  · Minh‑Sang Van Nguyen 3 © Springer Science+Business Media, LLC, part of Springer Nature 2019 Abstract In this study, ... Regarding MA schemes including orthogonal multiple access (OMA) and non-orthogonal multiple access (NOMA), these considered main categories are deployed to primarily pro-vide multiple access ... to imperfect jamming signal cancellation. It worth noting that channel gain in S–R link in case that existence of jamming signal is different with case that main channel of S–R link reserved for

Ngày tải lên: 22/11/2022, 14:09

... following actions: ! Complete Module 2, “Installing and Maintaining ISA Server,” in Course 2159A, Deploying and Managing Microsoft Internet Security and ! Complete Module 2, “Installing and Maintaining ... Module 5: Configuring Access for Remote Clients and Networks ! Complete Module 2, “Installing and Maintaining ISA Server,” in Course 2159A, Deploying and Managing Microsoft Internet Security ... Maintaining ISA Server,” in Course 2159A, Deploying and Managing Microsoft Internet Security and ! Complete Module 3, “Enabling Secure Internet Access,” in Course 2159A, Deploying and Managing

Ngày tải lên: 10/12/2013, 16:16

... Trang 1Understanding Delay in Packet Voice Networks Introduction When designing networks that transport voice over packet, frame, or cell infrastructures, it is important to ... backhauling, microwave links, and other factors found in carrier networks create many exceptions The other significant component of delay is from queuing within the wide-area network In a private ... only minimum buffering delay) In practice, over a number of network switch hops, it may not be necessary to assume the worst case The calculations in the following examples increase the initial

Ngày tải lên: 11/12/2013, 14:16

... Jagersfontein where it’s quite rife, Springfontein ja, I think it’s Springfontein number one And the reason for that is that in Springfontein you have, it’s on the N1, the Springfontein, you have ... was in Springfontein that most of commercial sex took place.And the reason for that (high rates of HIV infections in Springfontein) is that in Springfontein you have, it’s on the N1, the Springfontein, ... beginning to change.I think the communities are beginning to change I think it is beginning to change from that stigmatisation to sensitive and caring, ja I’m saying this because you’ll find

Ngày tải lên: 19/02/2014, 00:20

... central coordinating role in facilitating information sharing, with other actors remaining on the periphery However, that analysis also shows the important role other actors play in relaying information ... actors within the network, indicating that its reach beyond primary points of contact is relatively low Other influential actors, as indicated by high information sending and receiving means and ... discussion paper Trang 71 INTRODUCTION A paradigm shift occurred globally in agricultural research systems in the early 1990s consisting of changes in research financing and institutional arrangements

Ngày tải lên: 21/02/2014, 01:20

... extrinsic staining will be defined here as staining that can be easily removed by a normal prophylactic cleaning (Dayan et al 1983) Intrinsic staining is defined here as endogenous staining ... Rotstein Combining bleaching techniques 173 Bleaching and the microabrasion technique 193 Integrating bleaching with restorative dentistry 205 Combining bleaching with direct composite resin ... explain stains on teeth that start off as extrinsic stain and become intrinsic stain, such as nicotine staining; however, it is worth setting out in what follows as an explanation of extrinsic

Ngày tải lên: 06/03/2014, 11:20

... and efficient wireless access in challenging interference scenarios, for example, multiple networks deployed in the same geographical area and sharing a common band. In 1976, an ALOHA channel ... “Polarization Division Multiple Access With Polarization Modulation for LOS Wireless Communications” by Bin Cao, Qin-Yu Zhang, and Lin Jin discusses a potential multiple access and modulation ... algorithm increases only linearly with the number of users. In this algorithm, the different CFOs from different users destroy the orthogonality among training sequences and introduce multiple access...

Ngày tải lên: 21/06/2014, 17:20

... privacy-enhancing technologies. Information networks serve as the context in which privacy is investigated. Within information networks, the concepts of information ecosystems and con- tamination are introduced. ... different online registers or databases con- taining personal information may be combined by powerful search engines in order to get an apprehension about groups of individuals. In effect, this informa- tion ... and several startups joined in creat- ing Internet products and services. By the beginning of 2000, the Internet was supporting a great number of popular applications, including typical killer appli- cations...

Ngày tải lên: 16/01/2014, 16:33