WiMAX (Worldwide Interoperability for Microwave Access) uses the IEEE 802.16 standards for broadband wireless access over long distances. It supports both point-to-multipoint and mesh topologies with a connection-oriented MAC layer that provides quality of service. The physical layer uses OFDM, OFDMA, or single carrier modulation and the MAC layer supports various services classes for different types of traffic.
This document provides an overview of WiMAX and the IEEE 802.16 standards for broadband wireless access. It describes key aspects of the 802.16 MAC including its reference model, addressing, connection-oriented design, quality of service support, and uplink/downlink frame structures. It also summarizes the MAC convergence and common part sublayers, addressing, management connections, and bandwidth request mechanisms.
This document discusses WiMAX (Worldwide Interoperability for Microwave Access), the IEEE 802.16 wireless broadband standard. It provides an overview of key aspects of WiMAX including the 802.16 reference model, MAC features and services, QoS support, and bandwidth request mechanisms. The MAC supports connection-oriented transmissions, adaptive burst profiles, and flexible QoS with scheduling for various service classes including UGS, rtPS, nrtPS and BE.
WiMAX (IEEE 802.16) is a wireless broadband technology that provides transmission of data using a radio link instead of a cable infrastructure. It uses multiple access schemes such as OFDM and OFDMA to allow transmission to multiple users. The 802.16 standard defines the MAC layer which includes QoS, security, and bandwidth allocation to manage communication between the base station and subscriber stations.
The document discusses the key aspects of the IEEE 802.16 (WiMAX) standard for broadband wireless access. It describes the 802.16 MAC layer, including its reference model, convergence and common part sublayers, quality of service support, and security features. It also outlines the 802.16 PHY layer specifications and frame structures for different duplexing schemes.
IEEE 802.16 is a standard for wireless metropolitan area networks that provides broadband wireless access. It defines the air interface for fixed broadband wireless access systems, including the physical layer and media access control layer. The standard specifies point-to-point and point-to-multipoint topologies for wireless transmission between base stations and subscriber stations. It supports services such as fixed and mobile WiMAX that provide wireless internet access for homes, businesses, and mobile devices.
The document discusses 5G new radio (NR) physical layer resources including numerology, time-domain resources, frequency-domain resources, and space-domain resources. It provides details on key 5G NR concepts such as subcarrier spacing, symbols, slots and frames. Cyclic prefix length is determined based on subcarrier spacing to maintain consistent overhead. Slot formats in 5G NR provide more flexibility with symbol level uplink/downlink switching compared to LTE.
Wireless LAN technologies include WiFi (802.11 standards) and personal wireless networks like Bluetooth. 802.11 defines infrastructure networks with access points connected to wired networks, and ad-hoc networks without infrastructure. Key aspects of 802.11 include CSMA/CA for medium access, frame formats, and physical layer standards for radio (802.11a/b/g/n) and infrared transmission. Wireless networks offer mobility and flexibility compared to wired networks but have lower bandwidth and need to comply with regulations.
3. Introduction Wireless Local Area Networks.pptKp Sharma
Wireless LAN technologies include WiFi (802.11 standards) and personal wireless networks like Bluetooth. 802.11 defines infrastructure networks with access points connected to wired networks, and ad-hoc networks without infrastructure. Key aspects of 802.11 include CSMA/CA medium access, frame formats, and physical layer standards for radio frequencies (802.11a/b/g/n) and infrared (now obsolete). Wireless networks offer mobility and flexibility compared to wired networks but have lower bandwidth and can be affected by interference.
This document provides an overview of WiMAX and the IEEE 802.16 standards for broadband wireless access. It describes key aspects of the 802.16 MAC including its reference model, addressing, connection-oriented design, quality of service support, and uplink/downlink frame structures. It also summarizes the MAC convergence and common part sublayers, addressing, management connections, and bandwidth request mechanisms.
This document discusses WiMAX (Worldwide Interoperability for Microwave Access), the IEEE 802.16 wireless broadband standard. It provides an overview of key aspects of WiMAX including the 802.16 reference model, MAC features and services, QoS support, and bandwidth request mechanisms. The MAC supports connection-oriented transmissions, adaptive burst profiles, and flexible QoS with scheduling for various service classes including UGS, rtPS, nrtPS and BE.
WiMAX (IEEE 802.16) is a wireless broadband technology that provides transmission of data using a radio link instead of a cable infrastructure. It uses multiple access schemes such as OFDM and OFDMA to allow transmission to multiple users. The 802.16 standard defines the MAC layer which includes QoS, security, and bandwidth allocation to manage communication between the base station and subscriber stations.
The document discusses the key aspects of the IEEE 802.16 (WiMAX) standard for broadband wireless access. It describes the 802.16 MAC layer, including its reference model, convergence and common part sublayers, quality of service support, and security features. It also outlines the 802.16 PHY layer specifications and frame structures for different duplexing schemes.
IEEE 802.16 is a standard for wireless metropolitan area networks that provides broadband wireless access. It defines the air interface for fixed broadband wireless access systems, including the physical layer and media access control layer. The standard specifies point-to-point and point-to-multipoint topologies for wireless transmission between base stations and subscriber stations. It supports services such as fixed and mobile WiMAX that provide wireless internet access for homes, businesses, and mobile devices.
The document discusses 5G new radio (NR) physical layer resources including numerology, time-domain resources, frequency-domain resources, and space-domain resources. It provides details on key 5G NR concepts such as subcarrier spacing, symbols, slots and frames. Cyclic prefix length is determined based on subcarrier spacing to maintain consistent overhead. Slot formats in 5G NR provide more flexibility with symbol level uplink/downlink switching compared to LTE.
Wireless LAN technologies include WiFi (802.11 standards) and personal wireless networks like Bluetooth. 802.11 defines infrastructure networks with access points connected to wired networks, and ad-hoc networks without infrastructure. Key aspects of 802.11 include CSMA/CA for medium access, frame formats, and physical layer standards for radio (802.11a/b/g/n) and infrared transmission. Wireless networks offer mobility and flexibility compared to wired networks but have lower bandwidth and need to comply with regulations.
3. Introduction Wireless Local Area Networks.pptKp Sharma
Wireless LAN technologies include WiFi (802.11 standards) and personal wireless networks like Bluetooth. 802.11 defines infrastructure networks with access points connected to wired networks, and ad-hoc networks without infrastructure. Key aspects of 802.11 include CSMA/CA medium access, frame formats, and physical layer standards for radio frequencies (802.11a/b/g/n) and infrared (now obsolete). Wireless networks offer mobility and flexibility compared to wired networks but have lower bandwidth and can be affected by interference.
The document discusses IEEE 802.11 wireless LAN standards. It covers the physical layer specifications of 802.11b using HR/DSSS and 802.11a using OFDM. It also describes the MAC layer functions including CSMA/CA, fragmentation, power management, and quality of service enhancements. Security methods like WEP and 802.1x are summarized. Key concepts discussed are the BSS, ESS network architecture, and differences from Ethernet in medium access.
4G-Fourth Generation Mobile Communication SystemSafaet Hossain
Seminar on "4G-Fourth Generation Mobile Communication System" at UODA Auditorium, November 16,2013.
Technical Presented by: Ahmedul Quadir, Function Tester, Ericcson, Sweeden
Global System for Mobile (GSM) is a 2G digital cellular network standard. It uses Time Division Multiple Access (TDMA) and Frequency Division Duplexing (FDD) on radio carriers divided into 200 kHz channels. Each carrier can carry 8 voice channels using time division. GSM introduced digital voice coding, encryption, authentication and roaming between networks. Its architecture includes the Mobile Station (MS), Base Transceiver Station (BTS), Base Station Controller (BSC) and Mobile Switching Center (MSC) connected via standardized interfaces. GSM also uses frequency hopping and has various logical channels for control and traffic.
The document provides an overview of LTE (Long Term Evolution) Release 8. It discusses key requirements for LTE such as supporting high data rates, low latency, and an all-IP network. It describes the network architecture including components like eNodeB, MME, S-GW, and P-GW. It also covers functionality of these components and the protocol stack consisting of PDCP, RLC, MAC, and RRC layers. Mobility management, QoS, and comparisons to other technologies like HSPA+ and WiMAX are also summarized.
UMTS-WCDMA is a 3G mobile communication standard that uses CDMA technology. It uses wideband CDMA with a chip rate of 3.84 Mcps for its air interface along with orthogonal variable spreading factor codes. The standard defines protocols and procedures for cell search, handover, uplink and downlink physical channels, and support for multirate services through variable spreading factors. Long term targets for UMTS-WCDMA evolution include higher data rates up to 100 Mbps for full mobility and 1 Gbps for low mobility, as well as improved spectral efficiency.
WiMAX is a wireless technology that can provide broadband access over long distances. It uses wireless transmission in the 2-11 GHz range to connect users to a base station up to 50 km away. From the base station, users can access the internet and other public networks at speeds up to 70 Mbps shared among users. WiMAX allows both line-of-sight and non-line-of-sight connections using adaptive burst profiles. It has the potential to provide high-speed wireless internet access to areas not reached by cables and DSL.
The document provides an overview of ZigBee/IEEE 802.15.4 wireless technology. It discusses the need for low-power, low-cost wireless connectivity for applications like home automation, medical devices, and industrial sensors. It describes the ZigBee Alliance's role in developing networking and application standards on top of the IEEE 802.15.4 physical radio specification. Key features of ZigBee networks include low power consumption, large network capacity, low data rates, and flexibility for many applications.
International Journal of Engineering Research and Applications (IJERA) aims to cover the latest outstanding developments in the field of all Engineering Technologies & science.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
- IEEE 802.11n was a proposed amendment to the 802.11 wireless networking standard to improve network throughput and performance. It aimed to achieve speeds up to 540 Mbps.
- There were competing proposals for the standard from different industry groups that eventually merged into a single proposal.
- The standard was finalized in 2006 and added new technologies like MIMO and OFDM to existing 802.11 standards to boost speed and range of wireless networks.
- IEEE 802.11n was a proposed amendment to the 802.11 wireless networking standard to improve network throughput and performance. It aimed to achieve speeds up to 540 Mbps.
- There were competing proposals for the standard from different industry groups that eventually merged into a single proposal.
- The standard was finalized in 2006 and added new technologies like MIMO and OFDM to existing 802.11 standards to boost speed and range.
- IEEE 802.11n was a proposed amendment to the 802.11 wireless networking standard to improve network throughput and performance. It aimed to achieve speeds up to 540 Mbps.
- There were competing proposals for the standard from different industry groups that eventually merged into a single proposal.
- The standard was finalized in 2006 and added new technologies like MIMO and OFDM to existing 802.11 standards to significantly increase wireless network speeds and performance.
This document discusses various topics related to Long Term Evolution (LTE) including call flow, radio link failure, discontinuous reception (DRX), paging, scheduling, random access channel (RACH) procedure, self-organizing networks (SON), and quality of service (QoS). It provides details on the call flow process when a user equipment (UE) is powered on, performs initial cell selection and attachment, and establishes a default bearer. It also describes procedures for radio link failure, DRX, paging, scheduling, RACH, SON functions including self-configuration and optimization, and QoS with default and dedicated bearers.
WSN protocol 802.15.4 together with cc2420 seminars Salah Amean
WSN protocol 802.15.4 together with cc2420 seminars . It is based on the standand of ieee802.15.4 and data sheet of the radio transceiver cc2420.
Note that some slides are borrowed.
Voice Over U M T S Evolution From W C D M A, H S P A To L T EPengpeng Song
The document outlines the evolution of voice over UMTS networks from WCDMA to LTE. It discusses AMR voice codec characteristics and implementations of voice over UMTS networks in R99, HSPA+, and LTE standards. Key aspects covered include voice over IMS, circuit switched fallback, header compression, scheduling, and performance metrics like capacity and latency.
- IEEE 802.11p defines enhancements to 802.11 (WiFi) to support Intelligent Transportation Systems (ITS) by vehicle-to-vehicle and vehicle-to-infrastructure wireless communication. It uses dedicated 5.9GHz spectrum and improved robustness for high-speed mobile environments.
- The WAVE standards, including IEEE 1609.1-4 and SAE J2735, build upon 802.11p to provide networking services and standardized message formats for ITS applications. Key aspects include dedicated control and service channels for safety/control vs. other data, and synchronization of channel switching.
- The standards define protocols and formats for wireless access, security, networking
This document summarizes the physical layer design of LTE Release 8 and enhancements for LTE-Advanced. It describes the downlink and uplink multiple access schemes, reference signals, control signaling, data transmission procedures, UE categories, and support for frequency division duplex and time division duplex operation. The document provides an overview of the 3GPP release timeline and the specifications that define the LTE physical layer.
The document provides an overview of LTE and its evolution from previous cellular standards. It discusses the targets of LTE including high data rates up to 100 Mbps, low latency, high spectral efficiency, and flexibility in spectrum and bandwidth. It also describes the EPS architecture with E-UTRAN, EPC, and the air interface structure of LTE including OFDMA in the downlink and SC-FDMA in the uplink. Key layers like the PHY, MAC, and RLC layers are also summarized.
This document provides an overview of wireless local area networks (WLANs) and various IEEE 802.11 standards. It describes the characteristics and design goals of WLANs. It also compares infrastructure vs. ad-hoc network architectures and examines the physical layer, MAC layer, and management functions of 802.11. Specific standards like 802.11a, 802.11b, and future developments are outlined. The document provides details on aspects like channel selection, data rates, transmission ranges, and security considerations for different 802.11 technologies.
The document discusses key aspects of the IEEE 802.16 WiMAX standard. It describes WiMAX as providing broadband wireless access over long distances with high speeds. It outlines the MAC layer standards, including sublayers for convergence and management. It details the MAC frame structure, addressing, and scheduling priorities for different traffic types. Finally, it discusses advantages like mobility support, disadvantages like power consumption, and future applications of WiMAX technology.
This document describes the system equations for OTFS modulation and demodulation. At the transmitter, the signal is transformed from the delay-Doppler domain to the time-frequency domain using the inverse symplectic finite Fourier transform (ISFFT). It is then transmitted over the time-varying channel. At the receiver, the received signal is transformed back to the delay-Doppler domain using the symplectic finite Fourier transform (SFFT) after being transformed to the time-frequency domain via the Wigner transform. Maximum likelihood detection is then performed in the delay-Doppler domain for demodulation.
The document discusses IEEE 802.11 wireless LAN standards. It covers the physical layer specifications of 802.11b using HR/DSSS and 802.11a using OFDM. It also describes the MAC layer functions including CSMA/CA, fragmentation, power management, and quality of service enhancements. Security methods like WEP and 802.1x are summarized. Key concepts discussed are the BSS, ESS network architecture, and differences from Ethernet in medium access.
4G-Fourth Generation Mobile Communication SystemSafaet Hossain
Seminar on "4G-Fourth Generation Mobile Communication System" at UODA Auditorium, November 16,2013.
Technical Presented by: Ahmedul Quadir, Function Tester, Ericcson, Sweeden
Global System for Mobile (GSM) is a 2G digital cellular network standard. It uses Time Division Multiple Access (TDMA) and Frequency Division Duplexing (FDD) on radio carriers divided into 200 kHz channels. Each carrier can carry 8 voice channels using time division. GSM introduced digital voice coding, encryption, authentication and roaming between networks. Its architecture includes the Mobile Station (MS), Base Transceiver Station (BTS), Base Station Controller (BSC) and Mobile Switching Center (MSC) connected via standardized interfaces. GSM also uses frequency hopping and has various logical channels for control and traffic.
The document provides an overview of LTE (Long Term Evolution) Release 8. It discusses key requirements for LTE such as supporting high data rates, low latency, and an all-IP network. It describes the network architecture including components like eNodeB, MME, S-GW, and P-GW. It also covers functionality of these components and the protocol stack consisting of PDCP, RLC, MAC, and RRC layers. Mobility management, QoS, and comparisons to other technologies like HSPA+ and WiMAX are also summarized.
UMTS-WCDMA is a 3G mobile communication standard that uses CDMA technology. It uses wideband CDMA with a chip rate of 3.84 Mcps for its air interface along with orthogonal variable spreading factor codes. The standard defines protocols and procedures for cell search, handover, uplink and downlink physical channels, and support for multirate services through variable spreading factors. Long term targets for UMTS-WCDMA evolution include higher data rates up to 100 Mbps for full mobility and 1 Gbps for low mobility, as well as improved spectral efficiency.
WiMAX is a wireless technology that can provide broadband access over long distances. It uses wireless transmission in the 2-11 GHz range to connect users to a base station up to 50 km away. From the base station, users can access the internet and other public networks at speeds up to 70 Mbps shared among users. WiMAX allows both line-of-sight and non-line-of-sight connections using adaptive burst profiles. It has the potential to provide high-speed wireless internet access to areas not reached by cables and DSL.
The document provides an overview of ZigBee/IEEE 802.15.4 wireless technology. It discusses the need for low-power, low-cost wireless connectivity for applications like home automation, medical devices, and industrial sensors. It describes the ZigBee Alliance's role in developing networking and application standards on top of the IEEE 802.15.4 physical radio specification. Key features of ZigBee networks include low power consumption, large network capacity, low data rates, and flexibility for many applications.
International Journal of Engineering Research and Applications (IJERA) aims to cover the latest outstanding developments in the field of all Engineering Technologies & science.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
- IEEE 802.11n was a proposed amendment to the 802.11 wireless networking standard to improve network throughput and performance. It aimed to achieve speeds up to 540 Mbps.
- There were competing proposals for the standard from different industry groups that eventually merged into a single proposal.
- The standard was finalized in 2006 and added new technologies like MIMO and OFDM to existing 802.11 standards to boost speed and range of wireless networks.
- IEEE 802.11n was a proposed amendment to the 802.11 wireless networking standard to improve network throughput and performance. It aimed to achieve speeds up to 540 Mbps.
- There were competing proposals for the standard from different industry groups that eventually merged into a single proposal.
- The standard was finalized in 2006 and added new technologies like MIMO and OFDM to existing 802.11 standards to boost speed and range.
- IEEE 802.11n was a proposed amendment to the 802.11 wireless networking standard to improve network throughput and performance. It aimed to achieve speeds up to 540 Mbps.
- There were competing proposals for the standard from different industry groups that eventually merged into a single proposal.
- The standard was finalized in 2006 and added new technologies like MIMO and OFDM to existing 802.11 standards to significantly increase wireless network speeds and performance.
This document discusses various topics related to Long Term Evolution (LTE) including call flow, radio link failure, discontinuous reception (DRX), paging, scheduling, random access channel (RACH) procedure, self-organizing networks (SON), and quality of service (QoS). It provides details on the call flow process when a user equipment (UE) is powered on, performs initial cell selection and attachment, and establishes a default bearer. It also describes procedures for radio link failure, DRX, paging, scheduling, RACH, SON functions including self-configuration and optimization, and QoS with default and dedicated bearers.
WSN protocol 802.15.4 together with cc2420 seminars Salah Amean
WSN protocol 802.15.4 together with cc2420 seminars . It is based on the standand of ieee802.15.4 and data sheet of the radio transceiver cc2420.
Note that some slides are borrowed.
Voice Over U M T S Evolution From W C D M A, H S P A To L T EPengpeng Song
The document outlines the evolution of voice over UMTS networks from WCDMA to LTE. It discusses AMR voice codec characteristics and implementations of voice over UMTS networks in R99, HSPA+, and LTE standards. Key aspects covered include voice over IMS, circuit switched fallback, header compression, scheduling, and performance metrics like capacity and latency.
- IEEE 802.11p defines enhancements to 802.11 (WiFi) to support Intelligent Transportation Systems (ITS) by vehicle-to-vehicle and vehicle-to-infrastructure wireless communication. It uses dedicated 5.9GHz spectrum and improved robustness for high-speed mobile environments.
- The WAVE standards, including IEEE 1609.1-4 and SAE J2735, build upon 802.11p to provide networking services and standardized message formats for ITS applications. Key aspects include dedicated control and service channels for safety/control vs. other data, and synchronization of channel switching.
- The standards define protocols and formats for wireless access, security, networking
This document summarizes the physical layer design of LTE Release 8 and enhancements for LTE-Advanced. It describes the downlink and uplink multiple access schemes, reference signals, control signaling, data transmission procedures, UE categories, and support for frequency division duplex and time division duplex operation. The document provides an overview of the 3GPP release timeline and the specifications that define the LTE physical layer.
The document provides an overview of LTE and its evolution from previous cellular standards. It discusses the targets of LTE including high data rates up to 100 Mbps, low latency, high spectral efficiency, and flexibility in spectrum and bandwidth. It also describes the EPS architecture with E-UTRAN, EPC, and the air interface structure of LTE including OFDMA in the downlink and SC-FDMA in the uplink. Key layers like the PHY, MAC, and RLC layers are also summarized.
This document provides an overview of wireless local area networks (WLANs) and various IEEE 802.11 standards. It describes the characteristics and design goals of WLANs. It also compares infrastructure vs. ad-hoc network architectures and examines the physical layer, MAC layer, and management functions of 802.11. Specific standards like 802.11a, 802.11b, and future developments are outlined. The document provides details on aspects like channel selection, data rates, transmission ranges, and security considerations for different 802.11 technologies.
The document discusses key aspects of the IEEE 802.16 WiMAX standard. It describes WiMAX as providing broadband wireless access over long distances with high speeds. It outlines the MAC layer standards, including sublayers for convergence and management. It details the MAC frame structure, addressing, and scheduling priorities for different traffic types. Finally, it discusses advantages like mobility support, disadvantages like power consumption, and future applications of WiMAX technology.
This document describes the system equations for OTFS modulation and demodulation. At the transmitter, the signal is transformed from the delay-Doppler domain to the time-frequency domain using the inverse symplectic finite Fourier transform (ISFFT). It is then transmitted over the time-varying channel. At the receiver, the received signal is transformed back to the delay-Doppler domain using the symplectic finite Fourier transform (SFFT) after being transformed to the time-frequency domain via the Wigner transform. Maximum likelihood detection is then performed in the delay-Doppler domain for demodulation.
5G networking concepts are introduced, providing an overview of the evolution of mobile network generations from 1G to 5G. Key aspects covered include deployment timelines, increasing bandwidth capabilities, changing technologies and network architectures, and transitions to packet-switched core networks and all-IP infrastructures. 5G is described as providing over 1Gbps bandwidth and combining 4G technologies with wireless local area network/wide area network/personal area network capabilities using an all-packet network with dynamic access to information and variable devices, including artificial intelligence functions.
This document provides an overview of LTE architecture. It discusses key LTE parameters such as frequency range, mobility, coverage, and latency. It describes LTE data rates, duplexing and accessing techniques, modulation and coding schemes, and MIMO. It also outlines the main components of LTE architecture including the user equipment, E-UTRAN, EPC, and their functions. Finally, it lists some advantages of LTE such as high throughput and low latency, and one disadvantage which is the need for additional antennas.
The document provides an overview of the Open Systems Interconnection (OSI) model, which is a seven-layer structure that specifies requirements for communication between two computers. It describes each of the seven layers from the physical layer, which deals with physically moving data, to the session layer, which manages dialog between networked devices. The document also compares the OSI model to the TCP/IP model and explains how data is encapsulated as it moves between layers.
An electrical communication system consists of a transmitter that converts a signal into a form suitable for transmission through a channel, the channel being the physical medium used to send the signal, and a receiver that recovers the message from the received signal. Key elements of the system include modulation at the transmitter, noise and interference in the channel, and demodulation at the receiver. Wired communications rely on cables and wiring to transmit audio and visual data in a stable, high-speed manner.
Impartiality as per ISO /IEC 17025:2017 StandardMuhammadJazib15
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Build the Next Generation of Apps with the Einstein 1 Platform.
Rejoignez Philippe Ozil pour une session de workshops qui vous guidera à travers les détails de la plateforme Einstein 1, l'importance des données pour la création d'applications d'intelligence artificielle et les différents outils et technologies que Salesforce propose pour vous apporter tous les bénéfices de l'IA.
Prediction of Electrical Energy Efficiency Using Information on Consumer's Ac...PriyankaKilaniya
Energy efficiency has been important since the latter part of the last century. The main object of this survey is to determine the energy efficiency knowledge among consumers. Two separate districts in Bangladesh are selected to conduct the survey on households and showrooms about the energy and seller also. The survey uses the data to find some regression equations from which it is easy to predict energy efficiency knowledge. The data is analyzed and calculated based on five important criteria. The initial target was to find some factors that help predict a person's energy efficiency knowledge. From the survey, it is found that the energy efficiency awareness among the people of our country is very low. Relationships between household energy use behaviors are estimated using a unique dataset of about 40 households and 20 showrooms in Bangladesh's Chapainawabganj and Bagerhat districts. Knowledge of energy consumption and energy efficiency technology options is found to be associated with household use of energy conservation practices. Household characteristics also influence household energy use behavior. Younger household cohorts are more likely to adopt energy-efficient technologies and energy conservation practices and place primary importance on energy saving for environmental reasons. Education also influences attitudes toward energy conservation in Bangladesh. Low-education households indicate they primarily save electricity for the environment while high-education households indicate they are motivated by environmental concerns.
A high-Speed Communication System is based on the Design of a Bi-NoC Router, ...DharmaBanothu
The Network on Chip (NoC) has emerged as an effective
solution for intercommunication infrastructure within System on
Chip (SoC) designs, overcoming the limitations of traditional
methods that face significant bottlenecks. However, the complexity
of NoC design presents numerous challenges related to
performance metrics such as scalability, latency, power
consumption, and signal integrity. This project addresses the
issues within the router's memory unit and proposes an enhanced
memory structure. To achieve efficient data transfer, FIFO buffers
are implemented in distributed RAM and virtual channels for
FPGA-based NoC. The project introduces advanced FIFO-based
memory units within the NoC router, assessing their performance
in a Bi-directional NoC (Bi-NoC) configuration. The primary
objective is to reduce the router's workload while enhancing the
FIFO internal structure. To further improve data transfer speed,
a Bi-NoC with a self-configurable intercommunication channel is
suggested. Simulation and synthesis results demonstrate
guaranteed throughput, predictable latency, and equitable
network access, showing significant improvement over previous
designs
Applications of artificial Intelligence in Mechanical Engineering.pdfAtif Razi
Historically, mechanical engineering has relied heavily on human expertise and empirical methods to solve complex problems. With the introduction of computer-aided design (CAD) and finite element analysis (FEA), the field took its first steps towards digitization. These tools allowed engineers to simulate and analyze mechanical systems with greater accuracy and efficiency. However, the sheer volume of data generated by modern engineering systems and the increasing complexity of these systems have necessitated more advanced analytical tools, paving the way for AI.
AI offers the capability to process vast amounts of data, identify patterns, and make predictions with a level of speed and accuracy unattainable by traditional methods. This has profound implications for mechanical engineering, enabling more efficient design processes, predictive maintenance strategies, and optimized manufacturing operations. AI-driven tools can learn from historical data, adapt to new information, and continuously improve their performance, making them invaluable in tackling the multifaceted challenges of modern mechanical engineering.
Accident detection system project report.pdfKamal Acharya
The Rapid growth of technology and infrastructure has made our lives easier. The
advent of technology has also increased the traffic hazards and the road accidents take place
frequently which causes huge loss of life and property because of the poor emergency facilities.
Many lives could have been saved if emergency service could get accident information and
reach in time. Our project will provide an optimum solution to this draw back. A piezo electric
sensor can be used as a crash or rollover detector of the vehicle during and after a crash. With
signals from a piezo electric sensor, a severe accident can be recognized. According to this
project when a vehicle meets with an accident immediately piezo electric sensor will detect the
signal or if a car rolls over. Then with the help of GSM module and GPS module, the location
will be sent to the emergency contact. Then after conforming the location necessary action will
be taken. If the person meets with a small accident or if there is no serious threat to anyone’s
life, then the alert message can be terminated by the driver by a switch provided in order to
avoid wasting the valuable time of the medical rescue team.
Sri Guru Hargobind Ji - Bandi Chor Guru.pdfBalvir Singh
Sri Guru Hargobind Ji (19 June 1595 - 3 March 1644) is revered as the Sixth Nanak.
• On 25 May 1606 Guru Arjan nominated his son Sri Hargobind Ji as his successor. Shortly
afterwards, Guru Arjan was arrested, tortured and killed by order of the Mogul Emperor
Jahangir.
• Guru Hargobind's succession ceremony took place on 24 June 1606. He was barely
eleven years old when he became 6th Guru.
• As ordered by Guru Arjan Dev Ji, he put on two swords, one indicated his spiritual
authority (PIRI) and the other, his temporal authority (MIRI). He thus for the first time
initiated military tradition in the Sikh faith to resist religious persecution, protect
people’s freedom and independence to practice religion by choice. He transformed
Sikhs to be Saints and Soldier.
• He had a long tenure as Guru, lasting 37 years, 9 months and 3 days
2. What is WiMAX?
Worldwide Interoperability for
Microwave Access (WiMAX) is the
common name associated to the IEEE
802.16a/REVd/e standards.
These standards are issued by the IEEE
802.16 subgroup that originally covered
the Wireless Local Loop technologies
with radio spectrum from 10 to 66 GHz.
3. IEEE 802.16 -- Introduction
IEEE 802.16 (2001)
Air Interface for Fixed Broadband Wireless Access System MAC and
PHY Specifications for 10 – 66 GHZ (LoS)
One PHY: Single Carrier
Connection-oriented, TDM/TDMA MAC, QoS, Privacy
IEEE 802.16a (January 2003)
Amendment to 802.16, MAC Modifications and Additional PHY
Specifications for 2 – 11 GHz (NLoS)
Three PHYs: OFDM, OFDMA, Single Carrier
Additional MAC functions: OFDM and OFDMA PHY support, Mesh
topology support, ARQ
IEEE 802.16d (July 2004)
Combines both IEEE 802.16 and 802.16a
Some modifications to the MAC and PHY
IEEE 802.16e (2005?)
Amendment to 802.16-2004
MAC Modifications for limited mobility
4. IEEE 802.16 -- Introduction
Coverage range up to 50km and speeds up to
70Mbps(shared among users).
5. IEEE 802.16 -- Introduction
Source: WiMAX, making ubiquitous high-speed data services a reality, White Paper, Alcatel.
6. IEEE 802.16 MAC -- Highlights
WirelessMAN: Point-to-Multipoint and optional mesh
topology
Connection-oriented
Multiple Access: DL TDM & TDMA, UL TDMA;UL OFDMA
& TDMA, DL OFDMA & TDMA (Optional)
PHY considerations that affect the MAC
Duplex: TDD, FDD, FDX FDD BS and SS, HDX FDD SS
Adaptive burst profiles (Modulation and FEC) on both DL
and UL
Protocol-independent core (ATM, IP, Ethernet)
Flexible QoS offering (CBR, rt-VBR, nrt-VBR, BE)
Strong security support
9. Adaptive Burst Profiles
Burst profile: Modulation and FEC
On DL, multiple SSs can associate the
same DL burst
On UL, SS transmits in an given time slot
with a specific burst
Dynamically assigned according to link
conditions
Burst by burst
Trade-off capacity vs. robustness in real time
10. Duplex Scheme Support
The duplex scheme is Usually specified by
regulatory bodies, e.g., FCC
Time-Division Duplex (TDD)
Downlink & Uplink time share the same RF channel
Dynamic asymmetry
does not transmit & receive simultaneously (low
cost)
Frequency-Division Duplex (FDD)
Downlink & Uplink on separate RF channels
Full Duplexing (FDX): can Tx and Rx
simultaneously;
Half-duplexing (HDX) SSs supported (low cost)
11. IEEE 802.16 MAC
– OFDM PHY TDD Frame Structure
DL Subframe
Frame n-1
pre.
Time
Adaptive
Frame n Frame n+1
UL subframe
FCH
DL
burst 1
DL
burst n
UL
MAP
Broadcast Conrol msgs
... UL burst 1 UL burst m
DL
MAP
DCD
opt.
UCD
opt.
...
DL
burst 2
UL TDMA
DL TDM
pre. pre.
12. IEEE 802.16 MAC
– OFDM PHY FDD Frame Structure
DL Subframe
Frame n-1
pre.
Time
Broadcast
Control Msgs
Frame n Frame n+1
UL subframe
FCH
DL
burst 1
DL
burst k
...
DL TDMA
UL burst 1 UL burst m
DL
burst 2
DL
burst n
DL
burst k+1
...
DL TDM
...
UL TDMA
DL
MAP
UL
MAP
DCD
opt.
UCD
opt.
pre.
pre.
UL MAP for next
MAC frame UL
bursts
pre. pre.
13. FDD MAPs Time Relevance
frame
Broadcast
Full Duplex Capable User
Half Duplex T
erminal #1
Half Duplex T
erminal #2
UPLINK
DOWNLINK
DL
MAP
UL
MAP
DL
MAP
UL
MAP
14. IEEE 802.16 MAC addressing and
Identifiers
SS has 48-bit IEEE MAC address
BS has 48-bit base station ID
Not a MAC address
24-bit operator indicator
16-bit connection ID (CID)
32-bit service flow ID (SFID)
16-bit security association ID
(SAID)
15. IEEE 802.16 MAC
– Convergence Sub-Layer (CS)
ATM Convergence Sub-Layer:
Support for VP/VC switched connections
Support for end-to-end signaling of
dynamically created connections
ATM header suppression
Full QoS support
Packet Convergence Sub-Layer:
Initial support for Ethernet, VLAN, IPv4, and
IPv6
Payload header suppression
Full QoS support
16. IEEE 802.16 MAC -- CS
– Packet Convergence Sub-Layer
Functions:
Classification: mapping the higher layer PDUs
(Protocol Data Units) into appropriate MAC
connections
Payload header suppression (optional)
MAC SDU (Service Data Unit), i.e, CS PDU,
formatting
Packet PDU
(e.g., IP packet, Ethernet Packet)
PHSI
MAC SDU = CS PDU
Payload Header Suppression Index
Optional, Depending on upper layer
protocol
17. IEEE 802.16 MAC -- CPS
– MAC PDU Format
CRC
(optional)
MAC PDU payload (optional)
Generic MAC
Header
(6 bytes)
LEN
msb
(3)
H
T
CID msb (8)
LEN lsb (8)
Generic MAC Header Format
(Header Type (HT) = 0)
BW Req. Header Format
(Header Type (HT) =1)
msb lsb
E
C
Type (6 bits)
rs
v
C
I
EKS
(2)
rs
v
HCS (8)
CID lsb (8)
BW Req.
msb (8)
H
T
CID msb (8)
BWS Req. lsb (8)
E
C
Type (6 bits)
HCS (8)
CID lsb (8)
18. IEEE 802.16 MAC -- CPS
-- Three Types of MAC PDUs
Data MAC PDUs
HT = 0
Payloads are MAC SDUs/segments, i.e., data
from upper layer (CS PDUs)
Transmitted on data connections
Management MAC PDUs
HT =0
Payloads are MAC management messages or
IP packets encapsulated in MAC CS PDUs
Transmitted on management connections
BW Req. MAC PDUs
HT =1; and no payload, i.e., just a Header
19. IEEE 802.16 MAC -- CPS
– Data Packet Encapsulations
P
H
SI
MAC PDU
Ethernet Packet
Ethernet Packet
Packet PDU
(e.g., Ethernet)
CS PDU
(i.e., MAC SDU)
HT
FEC block 1
CRC
MAC PDU Payload
OFDM
symbol
1
PHY Burst
(e.g., TDMA burst)
Preamble
OFDM
symbol
2
OFDM
symbol
n
......
FEC
FEC Block 2 FEC block m
......
FEC Block 3
20. IEEE 802.16 MAC – CPS
-- MAC Management Connections
Each SS has 3 management connections in each
direction:
Basic Connection:
short and time-urgent MAC management messages
MAC mgmt messages as MAC PDU payloads
Primary Management connection:
longer and more delay tolerant MAC mgmt
messages
MAC mgmt messages as MAC PDU payloads
Secondary Management Connection:
Standard based mgmt messages, e.g., DHCP,
SNMP, …etc
IP packets based CS PDU as MAC PDU payload
21. IEEE 802.16 MAC – CPS
– MAC Management Messages
MAC mgmt message format:
MAC mgmt msg payload
mgmt
msg
HD
8 bits
• MAC mgmt msg can be sent on: Basic connections; Primary
mgmt connection; Broadcast connection; and initial ranging
connections
• 41 MAC mgmt msgs specified in 802.16
• The TLV (type/length/value) encoding scheme is used in MAC
mgmt msg, e.g., in UCD msg for UL burst profiles,
(type=1, length=1, value=1) QPSK modulation
(type=1, length=1, value=2) 16QAM modulation
(type=1, length=1, value=3) 64QAM modulation
22. IEEE 802.16 MAC – CPS
– MAC PDU Transmission
MAC PDUs are transmitted in PHY Bursts
The PHY burst can contain multiple FEC
blocks
MAC PDUs may span FEC block
boundaries
Concatenation
Packing
Segmentation
Sub-headers
23. IEEE 802.16 MAC – CPS
– MAC PDU Concatenation
MAC PDU 2
HT
FEC block 1
CRC
MAC PDU Payload
OFDM
symbol
1
PHY Burst
(e.g., TDMA burst)
Preamble
OFDM
symbol
2
OFDM
symbol
n
......
FEC
FEC Block 2 FEC block m
......
FEC Block 3
MAC PDU 1
HT CRC
MAC PDU Payload ......
MAC PDU k
HT CRC
MAC PDU
Payload
Multiple MAC PDUs are concatenated into the same PHY burst
24. IEEE 802.16 MAC – CPS
– MAC PDU Fragmentation
FEC block
1
OFDM
symbol
1
PHY Burst
Pre.
MAC SDU
OFDM
symbol
n1
......
FEC FEC Block
m1
......
MAC SDU
seg-1
HT CRC
MAC PDU Payload
HT CRC
MAC PDU
Payload
A MAC SDU can be fragmented into multiple segments, each
segment is encapsulated into one MAC PDU
FEC block
1
OFDM
symbol
1
PHY Burst
Pre.
OFDM
symbol
n2
......
FEC Block
m2
......
HT CRC
MAC PDU
Payload
MAC SDU
seg-2
MAC SDU
seg-3
F
S
H
F
S
H
Fragmentation
Sub-Header
(8 bits)
F
S
H
25. IEEE 802.16 MAC – CPS
– MAC PDU Packing
MAC
SDU 1
Fixed size MSDUs, e.g., ATM
Cells, on the same connection
HT CRC
MAC PDU Payload
HT CRC
Packing with fixed size MAC SDUs (no packing sub-header is needed)
......
PSH
MAC
SDU 2
MAC
SDU k
Packing with variable size MAC SDUs (Packing Sub-Heade is neeeded)
PSH ...... PSH
MAC SDU or
seg. 1 MAC SDU or seg 2
MAC SDU or
seg n
Variable size
MSDUs or MSDU
segments, e.g.,
IP packets, on
the same
connection
Packing
Sub-Heder
(16 bits)
26. IEEE 802.16 MAC – CPS
QoS
Three components of 802.16 QoS
Service flow QoS scheduling
Dynamic service establishment
Two-phase activation model (admit first, then activate)
Service Flow
A unidirectional MAC-layer transport service characterized
by a set of QoS parameters, e.g., latency, jitter, and
throughput assurances
Identified by a 32-bit SFID (Service Flow ID)
Three types of service flows
Provisioned: controlled by network management system
Admitted: the required resources reserved by BS, but not
active
Active: the required resources committed by the BS
27. IEEE 802.16 MAC – CPS
– Uplink Service Classes
UGS: Unsolicited Grant Services
rtPS: Real-time Polling Services
nrtPS: Non-real-time Polling
Services
BE: Best Effort
28. IEEE 802.16 MAC – CPS
– Uplink Services: UGS
UGS: Unsolicited Grant Services
For CBR or CBR-like services,
e.g., T1/E1.
The BS scheduler offers fixed size
UL BW grants on a real-time
periodic basis.
The SS does not need to send any
explicit UL BW req.
29. IEEE 802.16 MAC – CPS
– Uplink Services: rtPS
rtPS: Real-time Polling Services
For rt-VBR-like services, e.g., MPEG
video.
The BS scheduler offers real-time,
periodic, UL BW request opportunities.
The SS uses the offered UL BW req.
opportunity to specify the desired UL
BW grant.
The SS cannot use contention-based
BW req.
30. IEEE 802.16 MAC – CPS
– Uplink Services: nrtPS
nrtPS: non-real-time polling
services
For nrt-VBR-like services, such as,
bandwidth-intensive file transfer.
The BS scheduler shall provide timely
(on a order of a second or less) UL BW
request opportunities.
The SS can use contention-based BW
req. opportunities to send BW req.
31. IEEE 802.16 MAC – CPS
– Uplink Services: BE
BE: Best Effort
For best-effort traffic, e.g., HTTP,
SMTP.
The SS uses the contention-based
BW request opportunities.
32. IEEE 802.16 MAC – CPS
– Bandwidth Grant
BW grants are per Subscriber Station:
Allows real-time reaction to QoS need, i.e., SS may re-
distribute bandwidth among its connections, maintaining
QoS and service-level agreements
Lower overhead, i.e., less UL-MAP entries compare to grant
per connection
Off- loading base station’s work
Requires intelligent subscriber station to redistribute the
allocated BW among connections
33. IEEE 802.16 MAC – CPS
– BW Request/Grant Mechanisms
Implicit requests (UGS): No actual requests
BW request messages, i.e., BW req. header
Sends in either a contention-based BW req. slot or a
regular UL allocation for the SS;he special B
Requests up to 32 KB with a single message Request
Incremental or aggregate, as indicated by MAC header–
Piggybacked request (for non-UGS services only)
Presented in Grant Management (GM) sub-header in a
data MAC PDU of the same UL connection
is always incremental
Up to 32 KB per request for the CID
Poll-Me bit
Presented in the GM sub-header on a UGS connection
request a bandwidth req. opportunity for non-UGS services
34. IEEE 802.16 MAC – CPS
-- Contention UL Access
Two types of Contention based UL slots
Initial Ranging
Used for new SS to join the system
Requires a long preamble
BW Request
Used for sending BW req
Short preamble
Collision Detection and Resolution
Detection: SS does not get the expected response
in a given time
Resolution: a truncated binary exponential backoff
window
35. IEEE 802.16 MAC – CPS
UL Sub-Frame Structure
Source: http://www.cygnuscom.com/pdf/WP_PN_Article.pdf
36. IEEE 802.16 MAC – CPS
– Ranging
Ranging is a process of acquiring the
correct timing offset, and PHY
parameters, such as, Tx power level,
frequency offset, etc. so that the SS can
communicate with the BS correctly.
BS performs measurements and
feedback.
SS performs necessary adjustments.
Two types of Ranging:
Initial ranging: for a new SS to join the system
Periodic ranging (also called maintenance
ranging): dynamically maintain a good RF link.
37. IEEE 802.16 MAC – CPS
– Automatic Repeat reQuest (ARQ)
A Layer-2 sliding-window based flow control
mechanism.
Per connection basis.
Only effective to non-real-time applications.
Uses a 11-bit sequence number field.
Uses CRC-32 checksum of MAC PDU to check
data errors.
Maintain the same fragmentation structure for
Retransmission.
Optional.
38. IEEE 802.16 MAC
– Privacy Sub-layer (PS)
Two Major Functions:
Secures over-the-air transmissions
Protects from theft of service
Two component protocols:
Data encryption protocol
A client/server model based Key
management protocol (Privacy Key
Management, or PKM)
39. IEEE 802.16 MAC – PS
-- Security Associations
A set of privacy information, e.g.,
encryption keys, used encryption
algorithm
Three types of Security Associations (SAs)
Primary SA: established during initial registration
Static SA: provisioned within the BS
Dynamic SA: dynamically created on the fly
Identified by a 16-bit SAID
Connections are mapped to SAs
40. IEEE 802.16 MAC – PS
-- Multi-level Keys and Their Usage
Public Key
Contained in X.509 digital certificate
Issued by SS manufacturers
Used to encrypt AK
Authorization Key (AK)
Provided by BS to SS at authorization
Used to derive KEK
Key Encryption Key (KEK)
Derived from AK
Used to encrypt TEK
Traffic Encryption Key (TEK)
Provided by BS to SS at key exchange
Used to encrypt traffic data payload
41. IEEE 802.16 MAC – PS
-- Data Encryption
Use DES (Data Encryption Standard) in
CBC (Cipher Block Chaining) mode with
IV (Initialization Vector).
CBC IV is calculated from
IV parameter in TEK keying info; and
PHY synchronization field in DL-MAP.
Only MAC PDU payload (including sub-
headers) is encrypted.
MAC PDU headers are unencrypted.
Management messages are
unencrypted.
42. References
IEEE802.16-2004
Alcatel White Paper: WiMAX, making
ubiquitous high-speed data services a
reality
Intel White Paper: Understanding WiMAX
and 3G for Portable/Mobile Broadband
Wireless
WiMAX Forum: www.wimaxforum.com
http://en.wikipedia.org/wiki/WiMax
43. IEEE 802.16 MAC – commonly used
terms
BS – Base Station
SS – Subscriber Station, (i.e., CPE)
DL – Downlink, i.e. from BS to SS
UL – Uplink, i.e. from SS to BS
FDD – Frequency Division Duplex
TDD – Time Division Duplex
TDMA – Time Division Multiple Access
TDM – Time Division Multiplexing
OFDM – Orthogonal Frequency Division
Multiplexing
OFDMA - Orthogonal Frequency Division Multiple
Access
QoS – Quality of Service