This document proposes a methodology for incorporating uplink delay constraints into LTE cell planning for smart grid applications. It presents the following:
1) A semi-analytical approach is proposed to evaluate uplink transmission delays considering buffering delays before scheduling, packet transmission/retransmission delays over the air interface, and constraints from smart grid standards.
2) Analytical models are used to estimate buffering delays before scheduling based on queue length and service rate. Packet transmission delays are estimated considering packet segmentation, link adaptation, resource block allocation and retransmissions.
3) A cell planning algorithm is described that incorporates these delay metrics to validate compliance with smart grid delay constraints and determine the maximum cell range based on
Clustering based Time Slot Assignment Protocol for Improving Performance in U...journal ijrtem
Recently, numerous approaches have been proposed for designing medium access control (MAC)
in underwater acoustic networks (UANs). Some of those works tried to adapt MAC protocols proposed for
terrestrial networks. However, unique environmental characteristics of UANs make the MAC protocols hard to be
used in the UANs and degrade network performance. In order to improve network performance, COD-TS MAC
protocol was proposed. COD-TS focuses on both single hop and multi-hop mode and utilizes CDMA for
exchanging schedule information between cluster heads. COD-TS has shortcomings such as collisions, additional
energy consumption by exchanging schedule information and near-far effect of CDMA. To overcome above
shortcomings, we propose a clustering-based time slot assignment protocol. In the proposed protocol, nodes are
clustered, and each cluster head performs two-hop neighbor cluster discovery operation. And then, a cluster head
obtains its own relative position information. Finally, the cluster head assigns its own time slot for data
transmission based on the information. Simulation results show that the proposed protocol has always better
performance compared to the COD-TS.
A preamble-based approach for Providing QOS support in Wireless Sensor Networkdiala wedyan
The document discusses various MAC protocols for wireless sensor networks, including TDMA, Low Power Listening, XMAC, and BMAC protocols. It then describes a proposed Back off Preamble-based MAC protocol that uses different preamble lengths to prioritize medium access. The protocol is evaluated through simulation in OPNET Modeler, comparing its performance under different quality of service strategies for handling high and low priority traffic flows. The proposed protocol aims to provide reliable delivery and satisfy quality of service requirements for wireless sensor networks.
The Optimized Link State Routing Protocol (OLSR) is an IP routing protocol optimized for mobile ad hoc networks, which can also be used on other wireless ad hoc networks. OLSR uses hello and topology control (TC) messages to discover and then disseminate link state information throughout the mobile ad hoc network.
Contents which are covered here:
Classification of Ad-Hoc Routing Protocol
Link State Routing
Problems of Link State Routing
Optimized Link State Routing Protocol
1 Hop and 2 Hop Neighbors
Hello Packet
MPR Selection
Topology Table
MPR Information Declaration
*** Animated figure/diagram might not be visible in PDF view. Please consider it. ***
OLSR Model, OLSR Protocol, Optimized Link-State Routing Protocol
1) LEACH is a hierarchical routing protocol for wireless sensor networks that aims to lower energy consumption by forming clusters of nodes and rotating cluster head roles among nodes.
2) The document discusses several enhancements made to the original LEACH protocol to improve network lifetime, throughput, and coverage area, including E-LEACH, EHE-LEACH, and multi-level LEACH.
3) Simulation results show that the enhanced protocols increase network lifetime by 40-49% compared to the original LEACH protocol.
Performance Analysis and Simulation of OLSR Routing Protocol in MANET ijcnac
Mobile ad hoc network is a collection of wireless nodes that are communicate other
nodes (router) without using access point, infrastructure . Mobile ad-hoc network is an
autonomous system that means no need for depaentd other nodes it have own capability
to handle and controlling all funcitionlity, to sending and receiving all information form
one device to other device. MANET has power full feature that controlling itself by
dynamic nature, multihop,low power and configuration of the system. In this paper we
analyzing, simulation and implements the TC messages and HELLO Message by MPR of
OLSR routing performance checked at 200 nodes on Qualnet 5.0.2 simulator. In Qualnet
simulator to simulate and implement the performance of OLSR routing protocols takes
various performance metrics like hello message sent (HMS) , hello message received
(HMR), TC message generated (TCMG), TC message replied (TCMR), TC messages
received on Constant Bit Rate (CBR) using random waypoint model. In this paper check
the performance OLSR routing protocol gives effective performance for lage networks.
Enhancing Downlink Performance in Wireless Networks by Simultaneous Multiple ...ambitlick
This document discusses enhancing the downlink performance of wireless networks through simultaneous multiple packet transmission (MPT). MPT allows an access point to simultaneously transmit two packets to two distinct users, effectively doubling throughput. The paper formalizes scheduling packets for transmission as a maximum matching problem in a graph. It also presents a fast approximation algorithm for finding a matching and analyzes how MPT can increase maximum arrival rates and reduce packet delays.
Engineering Research Publication
Best International Journals, High Impact Journals,
International Journal of Engineering & Technical Research
ISSN : 2321-0869 (O) 2454-4698 (P)
www.erpublication.org
Fault tolerant wireless sensor mac protocol for efficient collision avoidancegraphhoc
In sensor networks communication by broadcast methods involves many hazards, especially collision. Several MAC layer protocols have been proposed to resolve the problem of collision namely ARBP, where the best achieved success rate is 90%. We hereby propose a MAC protocol which achieves a greater success rate (Success rate is defined as the percentage of delivered packets at the source reaching the destination successfully) by reducing the number of collisions, but by trading off the average propagation delay of transmission. Our proposed protocols are also shown to be more energy efficient in terms of energy dissipation per message delivery, compared to the currently existing protocol.
Clustering based Time Slot Assignment Protocol for Improving Performance in U...journal ijrtem
Recently, numerous approaches have been proposed for designing medium access control (MAC)
in underwater acoustic networks (UANs). Some of those works tried to adapt MAC protocols proposed for
terrestrial networks. However, unique environmental characteristics of UANs make the MAC protocols hard to be
used in the UANs and degrade network performance. In order to improve network performance, COD-TS MAC
protocol was proposed. COD-TS focuses on both single hop and multi-hop mode and utilizes CDMA for
exchanging schedule information between cluster heads. COD-TS has shortcomings such as collisions, additional
energy consumption by exchanging schedule information and near-far effect of CDMA. To overcome above
shortcomings, we propose a clustering-based time slot assignment protocol. In the proposed protocol, nodes are
clustered, and each cluster head performs two-hop neighbor cluster discovery operation. And then, a cluster head
obtains its own relative position information. Finally, the cluster head assigns its own time slot for data
transmission based on the information. Simulation results show that the proposed protocol has always better
performance compared to the COD-TS.
A preamble-based approach for Providing QOS support in Wireless Sensor Networkdiala wedyan
The document discusses various MAC protocols for wireless sensor networks, including TDMA, Low Power Listening, XMAC, and BMAC protocols. It then describes a proposed Back off Preamble-based MAC protocol that uses different preamble lengths to prioritize medium access. The protocol is evaluated through simulation in OPNET Modeler, comparing its performance under different quality of service strategies for handling high and low priority traffic flows. The proposed protocol aims to provide reliable delivery and satisfy quality of service requirements for wireless sensor networks.
The Optimized Link State Routing Protocol (OLSR) is an IP routing protocol optimized for mobile ad hoc networks, which can also be used on other wireless ad hoc networks. OLSR uses hello and topology control (TC) messages to discover and then disseminate link state information throughout the mobile ad hoc network.
Contents which are covered here:
Classification of Ad-Hoc Routing Protocol
Link State Routing
Problems of Link State Routing
Optimized Link State Routing Protocol
1 Hop and 2 Hop Neighbors
Hello Packet
MPR Selection
Topology Table
MPR Information Declaration
*** Animated figure/diagram might not be visible in PDF view. Please consider it. ***
OLSR Model, OLSR Protocol, Optimized Link-State Routing Protocol
1) LEACH is a hierarchical routing protocol for wireless sensor networks that aims to lower energy consumption by forming clusters of nodes and rotating cluster head roles among nodes.
2) The document discusses several enhancements made to the original LEACH protocol to improve network lifetime, throughput, and coverage area, including E-LEACH, EHE-LEACH, and multi-level LEACH.
3) Simulation results show that the enhanced protocols increase network lifetime by 40-49% compared to the original LEACH protocol.
Performance Analysis and Simulation of OLSR Routing Protocol in MANET ijcnac
Mobile ad hoc network is a collection of wireless nodes that are communicate other
nodes (router) without using access point, infrastructure . Mobile ad-hoc network is an
autonomous system that means no need for depaentd other nodes it have own capability
to handle and controlling all funcitionlity, to sending and receiving all information form
one device to other device. MANET has power full feature that controlling itself by
dynamic nature, multihop,low power and configuration of the system. In this paper we
analyzing, simulation and implements the TC messages and HELLO Message by MPR of
OLSR routing performance checked at 200 nodes on Qualnet 5.0.2 simulator. In Qualnet
simulator to simulate and implement the performance of OLSR routing protocols takes
various performance metrics like hello message sent (HMS) , hello message received
(HMR), TC message generated (TCMG), TC message replied (TCMR), TC messages
received on Constant Bit Rate (CBR) using random waypoint model. In this paper check
the performance OLSR routing protocol gives effective performance for lage networks.
Enhancing Downlink Performance in Wireless Networks by Simultaneous Multiple ...ambitlick
This document discusses enhancing the downlink performance of wireless networks through simultaneous multiple packet transmission (MPT). MPT allows an access point to simultaneously transmit two packets to two distinct users, effectively doubling throughput. The paper formalizes scheduling packets for transmission as a maximum matching problem in a graph. It also presents a fast approximation algorithm for finding a matching and analyzes how MPT can increase maximum arrival rates and reduce packet delays.
Engineering Research Publication
Best International Journals, High Impact Journals,
International Journal of Engineering & Technical Research
ISSN : 2321-0869 (O) 2454-4698 (P)
www.erpublication.org
Fault tolerant wireless sensor mac protocol for efficient collision avoidancegraphhoc
In sensor networks communication by broadcast methods involves many hazards, especially collision. Several MAC layer protocols have been proposed to resolve the problem of collision namely ARBP, where the best achieved success rate is 90%. We hereby propose a MAC protocol which achieves a greater success rate (Success rate is defined as the percentage of delivered packets at the source reaching the destination successfully) by reducing the number of collisions, but by trading off the average propagation delay of transmission. Our proposed protocols are also shown to be more energy efficient in terms of energy dissipation per message delivery, compared to the currently existing protocol.
This document summarizes a research paper that proposes a distributed protocol for assigning time slots in a wireless sensor network. The protocol has two phases: 1) Nodes fairly reserve multiple slots in a fixed frame to transmit data, so each node gets a fair share. 2) A centralized greedy algorithm is applied to reduce the frame length while ensuring each node gets at least one slot, making the frame as short as possible. Simulation results showed the protocol improves fairness of slot distribution and reduces frame length compared to an earlier algorithm.
To Get any Project for CSE, IT ECE, EEE Contact Me @ 09666155510, 09849539085 or mail us - ieeefinalsemprojects@gmail.com-Visit Our Website: www.finalyearprojects.org
Many energy-efficient Receiver Initiated Asynchronous Duty-Cycle MAC protocol for wireless sensor
networks (WSNs) have been proposed. Most nodes suffer from significant performance Degradation for burst traffic,
due to randomly waking up to communicate with each other. The proposed protocol is new receiver initiated
asynchronous duty-cycle MAC protocol for burst traffic . By adaptively adjusting beacon time of the receiver and it
schedules the sender listening time based on scheduled period, by this high energy efficiency and low end-to-end packet
delivery latency for burst traffic is achieved. We have evaluated the performance of MAC through detailed ns- 2
simulation. The simulation results show that this protocol reduce end-to-end packet delivery latency and energy
consumption under various data rates in different topologies compared with RI-MAC.
Keywords— Wireless sensor networks, duty-cycle, receiver-initiated, low latency, energy-efficient
With the rise of data-intensive mobile applications, network operators must find ways to increase network capacity to meet demand. MIMO (Multiple-Input Multiple-Output) techniques, which use multiple antennas at the transmission and reception ends, have the potential to significantly boost network throughput through spatial multiplexing. However, optimizing networks for MIMO's full benefits presents challenges, as MIMO works best under rich scattering conditions and requires accurate measurement of multipath environments. Real-world RF measurements tailored for MIMO networks can help operators overcome these challenges and maximize throughput gains from MIMO without additional spectrum or infrastructure.
Available network bandwidth schema to improve performance in tcp protocolsIJCNCJournal
The document describes a new congestion control scheme called New General Window Advertising (NGWA) for TCP. NGWA provides information on available network bandwidth to TCP endpoints. It stores the available bytes in router queues in a variable transmitted in IP headers. Receivers extract this value and use it to set the receive window size, indirectly informing senders of network capacity. Simulations show NGWA achieves stable transmission rates and fairness compared to TCP New Reno and standard TCP. An implementation in the Linux kernel proves NGWA's correct operation.
Use of NS-2 to Simulate MANET Routing AlgorithmsGiancarlo Romeo
The document summarizes the use of the NS-2 network simulator to simulate mobile ad hoc network (MANET) routing algorithms. It describes creating scenarios of mobile nodes, generating network traffic between nodes, running simulations of different routing protocols, and analyzing the resulting trace files to calculate throughput. Key aspects covered include the NS-2 architecture, scenario and traffic generation procedures, simulation and analysis procedures, and options configured for the simulations.
Quadrant Based DIR in CWin Adaptation Mechanism for Multihop Wireless NetworkIJCI JOURNAL
In Multihop Wireless Networks, traffic forwarding capability of each node varies according to its level of contention. Each node can yield its channel access opportunity to its neighbouring nodes, so that all the nodes can evenly share the channel and have similar forwarding capability. In this manner the wireless channel is utilized effectively, which is achieved using Contention Window Adaptation Mechanism (CWAM). This mechanism achieves a higher end-to-end throughout but consumes the network power to a higher level. So, a newly proposed algorithm Quadrant- Based Directional Routing Protocol (Q-DIR) is implemented as a cross-layer with CWAM, to reduce the total network power consumption through limited flooding and also reduce the routing overheads, which eventually increases overall network throughput. This algorithm limits the broadcast region to a quadrant where the source node and the destination nodes are located. Implementation of the algorithm is done in Linux based NS-2 simulator
Channel tracking uses interpolation to estimate channel conditions for data symbols based on previous pilot symbols transmitted on the same frequency. Frequency hopping instead has the transmitter regularly change frequency between subframes, expecting to gain diversity from different channel conditions on each frequency. The document compares algorithms for channel estimation using channel tracking versus frequency hopping in an LTE uplink receiver. Performance is evaluated through simulation under various channel models.
Multihop Routing In Camera Sensor NetworksChuka Okoye
This poster abstract summarizes an experimental study of multihop routing in camera sensor networks. The experiments tested the Collection Tree Protocol (CTP) using CITRIC camera motes and TelosB motes. The experiments varied payload size and delay between packet transmissions to evaluate data rate, reception rate, and latency over different hop counts. The results show that there is a tradeoff between reception rate and latency. Adding a delay between transmissions can improve both data rate and reception rate compared to best effort transmission. The optimal delay depends on the network density and hop count.
The document summarizes the research scope and contributions of the author's PhD dissertation on medium access control (MAC) protocols for cognitive radio networks (CRNs). It discusses four past research areas: (1) CMAC protocol design with parallel spectrum sensing, (2) CMAC protocol with sequential sensing, (3) CMAC protocol with cooperative sensing, and (4) asynchronous full-duplex CMAC protocol. It also outlines three potential future research directions: (1) multi-channel MAC protocol design for full-duplex CRNs, (2) cross-layer CMAC and routing design for multi-hop CRNs, and (3) joint cognitive protocol and data processing design for smart grid applications.
This is the bottom sublayer of the Data Link Layer. This Chapter is especially relevant for LANs.
4.1 The Channel Allocation Problem
How to allocate a single channel among multiple users.
4.2 Multiple Access Protocols
How to handle contention for the use of a channel.
4.3 IEEE Standards for LANs
How do the protocols of the last sections apply to real systems. Here we talk about the actual standards in use.
4.4 Bridges
Ways of connecting networks together.
4.5 High Speed LANs
Directions in high speed networks.
Simulation & comparison of aodv & dsr protocolPrafull Johri
This document summarizes and compares two reactive routing protocols - AODV and DSR. It discusses how NS2 was extended to simulate wireless networks and the two protocols. AODV uses route discovery to find paths, maintains route tables, and can locally repair broken links. DSR also uses route discovery but source routes are carried in packet headers. While AODV has lower initial packet loss, DSR performance improves over time, so either protocol can be used for longer simulations.
This newsletter summarizes events and programs of the Tustin Police Officers Association. It discusses the "thin blue line" concept of police protecting communities and supporting each other like a family. It then outlines several community events the TPOA has participated in or will participate in, including attending officer funerals, a youth football tournament, a moustache growing contest to fundraise for turkey dinners, and partnering with a running event where proceeds will support the TPOA. It also discusses efforts to include and recognize retired officers and create an outreach center.
Steph has 9 years of experience in marketing and graphic design, including over 2 years as a Marketing Executive at Cheng Hua Engineering Company. She holds a Bachelor's degree in Professional Design from Limkokwing University and is seeking a new role with an expected salary of MYR 4,600-5,200 per month. She is proficient in Bahasa Malaysia, Chinese, and English and prefers to work in Subang Jaya, Selangor.
This document provides information and proposes plans for the village of Bheemadevarapally in Telangana, India as part of the "Know Your District - Plan Your District" initiative. It outlines Mahatma Gandhi's vision for model villages. It then describes the village's resources, demographics, and objectives for village development which include improving basic amenities, education, sanitation, afforestation, and livelihood opportunities. Charts and maps generated through a government application show the village's assets and population breakdown by age, gender, and caste from the 2001 and 2011 censuses. Declines in child population and sex ratio since 2011 are noted as priorities to address.
The document provides an overview of the activities and programs of the Professional Fire Fighters of Wisconsin Charitable Foundation in 2016. It discusses the expansion of programs to include burn survivor support, fire prevention education, and support for firefighters. Key events included the summer camp for burn injured youth, leadership programs for burn survivors, and distribution of a fire safety newspaper supplement to schools. The foundation also welcomed new board members and an executive director to continue growing its mission.
La nulidad en los procesos de selección puede ser declarada por la entidad o por el Tribunal cuando se detecten vicios en el proceso que transgredan la normativa. La entidad puede declarar la nulidad de oficio hasta antes de la suscripción del contrato, mientras que el Tribunal puede hacerlo al revisar los casos. El objetivo de la nulidad es retrotraer el proceso a la etapa donde ocurrió el vicio para corregirlo y ajustarlo a derecho.
Tecnicas tradicionales para el registro,almacenimiento y recuperacion dealfo_cristiano
El proceso documentario consta de varios pasos: la selección de documentos a través de compra, canje o donación, el análisis de los elementos más significativos de cada documento mediante catalogación, clasificación y análisis de contenido, la búsqueda y recuperación rápida de la información, y la difusión de la información registrada a los usuarios.
La selección femenina de voleibol de Perú ha tenido éxito a nivel mundial con un subcampeonato mundial, un subcampeonato olímpico y docena de campeonatos sudamericanos, mientras que la selección masculina aún no ha podido sobresalir. El voleibol llegó a Perú en 1911 de la mano de profesores estadounidenses y se convirtió en uno de los deportes más populares, especialmente después de que Perú comenzara a ganar campeonatos sudamericanos a partir de 1967 b
This document summarizes a research paper that proposes a distributed protocol for assigning time slots in a wireless sensor network. The protocol has two phases: 1) Nodes fairly reserve multiple slots in a fixed frame to transmit data, so each node gets a fair share. 2) A centralized greedy algorithm is applied to reduce the frame length while ensuring each node gets at least one slot, making the frame as short as possible. Simulation results showed the protocol improves fairness of slot distribution and reduces frame length compared to an earlier algorithm.
To Get any Project for CSE, IT ECE, EEE Contact Me @ 09666155510, 09849539085 or mail us - ieeefinalsemprojects@gmail.com-Visit Our Website: www.finalyearprojects.org
Many energy-efficient Receiver Initiated Asynchronous Duty-Cycle MAC protocol for wireless sensor
networks (WSNs) have been proposed. Most nodes suffer from significant performance Degradation for burst traffic,
due to randomly waking up to communicate with each other. The proposed protocol is new receiver initiated
asynchronous duty-cycle MAC protocol for burst traffic . By adaptively adjusting beacon time of the receiver and it
schedules the sender listening time based on scheduled period, by this high energy efficiency and low end-to-end packet
delivery latency for burst traffic is achieved. We have evaluated the performance of MAC through detailed ns- 2
simulation. The simulation results show that this protocol reduce end-to-end packet delivery latency and energy
consumption under various data rates in different topologies compared with RI-MAC.
Keywords— Wireless sensor networks, duty-cycle, receiver-initiated, low latency, energy-efficient
With the rise of data-intensive mobile applications, network operators must find ways to increase network capacity to meet demand. MIMO (Multiple-Input Multiple-Output) techniques, which use multiple antennas at the transmission and reception ends, have the potential to significantly boost network throughput through spatial multiplexing. However, optimizing networks for MIMO's full benefits presents challenges, as MIMO works best under rich scattering conditions and requires accurate measurement of multipath environments. Real-world RF measurements tailored for MIMO networks can help operators overcome these challenges and maximize throughput gains from MIMO without additional spectrum or infrastructure.
Available network bandwidth schema to improve performance in tcp protocolsIJCNCJournal
The document describes a new congestion control scheme called New General Window Advertising (NGWA) for TCP. NGWA provides information on available network bandwidth to TCP endpoints. It stores the available bytes in router queues in a variable transmitted in IP headers. Receivers extract this value and use it to set the receive window size, indirectly informing senders of network capacity. Simulations show NGWA achieves stable transmission rates and fairness compared to TCP New Reno and standard TCP. An implementation in the Linux kernel proves NGWA's correct operation.
Use of NS-2 to Simulate MANET Routing AlgorithmsGiancarlo Romeo
The document summarizes the use of the NS-2 network simulator to simulate mobile ad hoc network (MANET) routing algorithms. It describes creating scenarios of mobile nodes, generating network traffic between nodes, running simulations of different routing protocols, and analyzing the resulting trace files to calculate throughput. Key aspects covered include the NS-2 architecture, scenario and traffic generation procedures, simulation and analysis procedures, and options configured for the simulations.
Quadrant Based DIR in CWin Adaptation Mechanism for Multihop Wireless NetworkIJCI JOURNAL
In Multihop Wireless Networks, traffic forwarding capability of each node varies according to its level of contention. Each node can yield its channel access opportunity to its neighbouring nodes, so that all the nodes can evenly share the channel and have similar forwarding capability. In this manner the wireless channel is utilized effectively, which is achieved using Contention Window Adaptation Mechanism (CWAM). This mechanism achieves a higher end-to-end throughout but consumes the network power to a higher level. So, a newly proposed algorithm Quadrant- Based Directional Routing Protocol (Q-DIR) is implemented as a cross-layer with CWAM, to reduce the total network power consumption through limited flooding and also reduce the routing overheads, which eventually increases overall network throughput. This algorithm limits the broadcast region to a quadrant where the source node and the destination nodes are located. Implementation of the algorithm is done in Linux based NS-2 simulator
Channel tracking uses interpolation to estimate channel conditions for data symbols based on previous pilot symbols transmitted on the same frequency. Frequency hopping instead has the transmitter regularly change frequency between subframes, expecting to gain diversity from different channel conditions on each frequency. The document compares algorithms for channel estimation using channel tracking versus frequency hopping in an LTE uplink receiver. Performance is evaluated through simulation under various channel models.
Multihop Routing In Camera Sensor NetworksChuka Okoye
This poster abstract summarizes an experimental study of multihop routing in camera sensor networks. The experiments tested the Collection Tree Protocol (CTP) using CITRIC camera motes and TelosB motes. The experiments varied payload size and delay between packet transmissions to evaluate data rate, reception rate, and latency over different hop counts. The results show that there is a tradeoff between reception rate and latency. Adding a delay between transmissions can improve both data rate and reception rate compared to best effort transmission. The optimal delay depends on the network density and hop count.
The document summarizes the research scope and contributions of the author's PhD dissertation on medium access control (MAC) protocols for cognitive radio networks (CRNs). It discusses four past research areas: (1) CMAC protocol design with parallel spectrum sensing, (2) CMAC protocol with sequential sensing, (3) CMAC protocol with cooperative sensing, and (4) asynchronous full-duplex CMAC protocol. It also outlines three potential future research directions: (1) multi-channel MAC protocol design for full-duplex CRNs, (2) cross-layer CMAC and routing design for multi-hop CRNs, and (3) joint cognitive protocol and data processing design for smart grid applications.
This is the bottom sublayer of the Data Link Layer. This Chapter is especially relevant for LANs.
4.1 The Channel Allocation Problem
How to allocate a single channel among multiple users.
4.2 Multiple Access Protocols
How to handle contention for the use of a channel.
4.3 IEEE Standards for LANs
How do the protocols of the last sections apply to real systems. Here we talk about the actual standards in use.
4.4 Bridges
Ways of connecting networks together.
4.5 High Speed LANs
Directions in high speed networks.
Simulation & comparison of aodv & dsr protocolPrafull Johri
This document summarizes and compares two reactive routing protocols - AODV and DSR. It discusses how NS2 was extended to simulate wireless networks and the two protocols. AODV uses route discovery to find paths, maintains route tables, and can locally repair broken links. DSR also uses route discovery but source routes are carried in packet headers. While AODV has lower initial packet loss, DSR performance improves over time, so either protocol can be used for longer simulations.
This newsletter summarizes events and programs of the Tustin Police Officers Association. It discusses the "thin blue line" concept of police protecting communities and supporting each other like a family. It then outlines several community events the TPOA has participated in or will participate in, including attending officer funerals, a youth football tournament, a moustache growing contest to fundraise for turkey dinners, and partnering with a running event where proceeds will support the TPOA. It also discusses efforts to include and recognize retired officers and create an outreach center.
Steph has 9 years of experience in marketing and graphic design, including over 2 years as a Marketing Executive at Cheng Hua Engineering Company. She holds a Bachelor's degree in Professional Design from Limkokwing University and is seeking a new role with an expected salary of MYR 4,600-5,200 per month. She is proficient in Bahasa Malaysia, Chinese, and English and prefers to work in Subang Jaya, Selangor.
This document provides information and proposes plans for the village of Bheemadevarapally in Telangana, India as part of the "Know Your District - Plan Your District" initiative. It outlines Mahatma Gandhi's vision for model villages. It then describes the village's resources, demographics, and objectives for village development which include improving basic amenities, education, sanitation, afforestation, and livelihood opportunities. Charts and maps generated through a government application show the village's assets and population breakdown by age, gender, and caste from the 2001 and 2011 censuses. Declines in child population and sex ratio since 2011 are noted as priorities to address.
The document provides an overview of the activities and programs of the Professional Fire Fighters of Wisconsin Charitable Foundation in 2016. It discusses the expansion of programs to include burn survivor support, fire prevention education, and support for firefighters. Key events included the summer camp for burn injured youth, leadership programs for burn survivors, and distribution of a fire safety newspaper supplement to schools. The foundation also welcomed new board members and an executive director to continue growing its mission.
La nulidad en los procesos de selección puede ser declarada por la entidad o por el Tribunal cuando se detecten vicios en el proceso que transgredan la normativa. La entidad puede declarar la nulidad de oficio hasta antes de la suscripción del contrato, mientras que el Tribunal puede hacerlo al revisar los casos. El objetivo de la nulidad es retrotraer el proceso a la etapa donde ocurrió el vicio para corregirlo y ajustarlo a derecho.
Tecnicas tradicionales para el registro,almacenimiento y recuperacion dealfo_cristiano
El proceso documentario consta de varios pasos: la selección de documentos a través de compra, canje o donación, el análisis de los elementos más significativos de cada documento mediante catalogación, clasificación y análisis de contenido, la búsqueda y recuperación rápida de la información, y la difusión de la información registrada a los usuarios.
La selección femenina de voleibol de Perú ha tenido éxito a nivel mundial con un subcampeonato mundial, un subcampeonato olímpico y docena de campeonatos sudamericanos, mientras que la selección masculina aún no ha podido sobresalir. El voleibol llegó a Perú en 1911 de la mano de profesores estadounidenses y se convirtió en uno de los deportes más populares, especialmente después de que Perú comenzara a ganar campeonatos sudamericanos a partir de 1967 b
Este documento presenta la Red de Parques Nacionales de España, que protege espacios de interés ecológico. Describe 14 parques nacionales, incluyendo sus características de flora, fauna y geología únicas, y valores ecológicos. También proporciona información sobre la superficie total protegida por cada parque, que en conjunto suman más de 1,5 millones de hectáreas de territorio terrestre y marino bajo especial protección.
El documento describe las características y usos de las presentaciones digitales. Explica que se usan cada vez más en entornos profesionales y que deben diseñarse de forma atractiva para mantener la atención del público. También menciona algunos programas comunes para crear presentaciones como PowerPoint, Impress, Keynote y Google Docs.
Firas M.K. Aburajab AlTamemi is a Jordanian male who has over 15 years of experience in regional management roles. He has expertise in areas like operations management, sales and marketing, and performance management. He is skilled in time management, motivation, and communication. Currently he works as a regional manager for Arabtec Construction Machinery in KSA, where he is responsible for branches in central and eastern regions. Previously he held management and sales positions in Jordan, KSA, and Iraq. He has a bachelor's degree in mechanical engineering technology.
the biological indicators studies of zooplanktonIJEAB
The study of biological indicators for zooplanktonis important factors in environmental studies to show the extent of the surrounding organisms, distribution and deployment environment affected. Zooplankton samples were collected from three stations on the Tigris River in the city of Baghdad using zooplankton net, specimens preserved and laboratory-diagnosed using internationally recognized classifications. Results show through the presence of relatively high abundance of zooplankton in the three stations and not affected by the city in addition to the species abundance is the other index gave few differences between stations, a lack of environmental pressures on these organisms in the station directory. Also, Shannon-Weiner diversity Indexpointer gave no significant differences between the study stations.
Este documento proporciona información sobre la historia y reglas de la gimnasia rítmica. Explica que la gimnasia rítmica combina elementos de ballet, gimnasia y danza utilizando aparatos como la cuerda, el aro, la pelota, las mazas y la cinta. También describe el sistema de puntuación, los elementos que se evalúan y las posibles penalizaciones.
The document discusses different types of waste including solid, liquid, organic, recyclable, and hazardous waste. It also discusses proper waste management techniques like reducing, reusing, and recycling waste as well as different methods for waste disposal including incineration, landfilling, compaction, pyrolysis, and composting. Improper waste management can cause environmental problems like water, soil, air pollution and adverse health effects.
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Iaetsd a novel scheduling algorithms for mimo based wireless networksIaetsd Iaetsd
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Clustering based Time Slot Assignment Protocol for Improving Performance in U...IJRTEMJOURNAL
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The document proposes a new multicast routing protocol for mobile ad hoc networks (MANETs) that provides bandwidth guarantees while reducing total bandwidth consumption. It constructs multiple multicast trees to fully utilize residual bandwidth across paths. Randomized network coding is used so redundant packets are avoided and destinations receive innovative coded packets from different routes. The protocol estimates available bandwidth on routes using a variable bit rate to improve accuracy. Simulation results show the protocol reduces delay and retransmission rates compared to existing protocols, improving bandwidth usage in MANETs.
Osc mac duty cycle with multi helpers ct mode wi-lem technology in wireless s...ijwmn
Recently, Wireless Sensor Networks (WSNs) grow to be one of the dominant technology trends; new needs
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module and manages the medium sharing. In this work we use OSC-MAC tackles combining with the
performance of cooperative transmission (CT) in multi-hop WSN and the Wi-Lem technology
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congestion window which provides higher throughput and shorter delay than the traditional TCP. Various Backoff algorithms that are used to adjust Contention Window are simulatedusing NS2 along with modified TCP and their performance are analyzed to depict the influence of Contention Window in TCP performance considering the metrics such as throughput, delay, packet loss and end-to-end delay
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This document proposes an improvement to the Multi-slot Coded ALOHA (MuSCA) random multiple access scheme for satellite communications. The improvement involves applying variable code rates and irregular user degree distributions, where the code rate and degree for each user are selected according to a probability distribution. This allows the system to achieve higher throughput compared to the original MuSCA scheme and other related schemes like Contention Resolution Diversity Slotted ALOHA (CRDSA). The document describes how the system would work, including encoding data into codewords that are split into multiple bursts and transmitted on random slots, and decoding the received signal using successive interference cancellation. It analyzes the potential throughput gain from optimizing the irregular degree distribution.
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4..[26 36]signal strength based congestion control in manetAlexander Decker
This document discusses several algorithms and approaches for improving TCP performance in mobile ad hoc networks (MANETs) using signal strength measurements:
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4. Gray zone prediction and
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1) A semi-analytical approach is proposed to evaluate uplink transmission delays considering buffering delays before scheduling, packet transmission/retransmission delays over the air interface, and constraints from smart grid standards.
2) Analytical models are used to estimate buffering delays before scheduling based on queue length and service rate. Packet transmission delays are estimated considering packet segmentation, link adaptation, resource block allocation and retransmissions.
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1. LTE Uplink Delay Constraints for Smart Grid
Applications
Spiros Louvros, member IEEE, Michalis Paraskevas, Vassilis Triantafyllou, Agamemnon Baltagiannis
Abstract—LTE cell planning requires special constraints in
case of smart grid applications. Cell planners decide about the
cell coverage mostly based on worst radio conditions (cell edge)
acceptable level of minimum throughput, but not on delay
constraints which are of extreme importance for smart grid
solutions. In this paper a semi-analytical approach for uplink
cell planning with delay constraints for smart grid applications
is proposed, using theoretical outputs from analytical
mathematical models combined with real measurements from
drive test.
Keywords-LTE; smart grid; uplink delay
I. INTRODUCTION
Long Term Evolution [LTE] is the evolution of High
Speed Packet Access [HSPA] cellular networks towards 4G
[1]. Lately, on international literature, there are research
papers and technical reports for LTE applications over smart
grid networks [2-4]. However effective EUTRAN radio
delay and latency constraints are never considered so far on
international literature regarding cell planning algorithms;
nevertheless it is extremely important to include delay
constraints into cell planning analysis since LTE 3GPP
standards and smart grid IEC 61850-5 standards [5] define
strict restrictions on radio delays. In this paper we propose a
methodology of correcting initial cell coverage planning
using delay constraints, based on a semi-analytically
evaluated relation among packet transmission delays, cell
edge path losses, MAC retransmissions and real drive test
measurements. MAC scheduler provides uplink decisions
mainly based on γRB measurements per resource block (RB),
required Quality of Service received from core network
(Quality Class Identifier – QCI) [6] and cell load conditions
including interference and availability on RB together with
fast scheduling [7]. Rest of the paper is organized in the
following way: in section II we present service buffering
delay estimation before MAC scheduler functionality. In
section III packet transmission/retransmission delays over air
interface are considered. In section IV the proposed cell
planning algorithm with emphasis on smart grid delay
constraints is analyzed in concrete steps, where all
calculations are detailed and analytically explained. Finally
on section V conclusions are summarized.
II. BUFFERING BEFORE SCHEDULING DELAY ESTIMATION
A generalized queue system is considered, with one
single server (MAC scheduler), m channels (RB resources)
in parallel, finite queue length, Poisson λ packets per second
(although lately has been found that other distributions fit the
packet arrival, Poisson is still a very good approximation)
and service time μ0. Moreover transit time effects are
neglected on this analysis. In order to have queue system in
equilibrium we do suppose that per 1 ms TTI always m > λ.
Define πn the probability of existing n packets in queue at a
given time τ and pn the probability that zero packets exist in
the queue as long as n packets exist in the server at given
time τ, overall probability analytical solution πn will be [8]:
1 2
1
0 1 2 11 1 1 1
mn
n zm
n m
m z z z z z z
z
z z z z e
To analytically calculate πn it is needed to expand the
right part of (1) into the Laurent series around z = 0, where
πn for n = 0, 1, 2,…,n will be the coefficients of zn
after the
expansion is performed. Consider the case of m = 1 (MAC
scheduler considers each packet as a unique SDU service
input) the numerator is degenerated into a simple polynomial
of order one with one single real root
1 1
0 0 1
0 1 0 1 0
0
0 1, 0
n
n m
n n n
z z
z z z z
The polynomial expansion coefficients, after expanding
the polynomial into Laurent series around z = 0 and
substituting λ/μ = ρ as the utilization factor, are becoming:
1
0
2 2
1 1
1
1 1 1
1 1 ....
n
n z
n
z
z z
ze
e z
e e z
From expansion the general term is calculated as:
1
1
1
1 1
!
1 1
1 !
n k
n
n k k
n
k
n k
n
n k k
k
k n
k
e
n k
k
e
n k
Finally average expected delay is calculated as:
2. Fig. 1. Mean expected buffering delay (ms)
1
1 1
1
1 1
1 1
!
1 1
1 !
n
n
n k
n
n k k
n k
n k
n
n k
n k
k n
k
W n
k
n e
n k
k
n e
n k
In Fig. 1 the average expected delay is plotted
against offered load ρ = λ/μ considered the arrival rate of
packets λ at the buffer and the service rate of μ packets going
from buffer inside the scheduler system.
III. SCHEDULING TRANSMISSION DELAY ESTIMATION
IP packets will be segmented into many RLC/MAC
Signaling Data Units (SDUs) to be mapped into OFDM RB
and transmitted over air interface. Between user equipment
(UE) and eNodeb each MAC packet is supposed to be
transmitted completely over the air interface before starting
transmission of next MAC packet in a time transmission
interval duration of Ts = 1ms due to Hybrid ARQ (HARQ)
MAC functionality . Moreover multiple consecutive resource
blocks nRB might be selected from MAC scheduler for uplink
transmission, minimizing the transmission latency and
improving the UE throughput. Our analysis will be based on
transmissions of IP packets over RLC/MAC blocks based on
channel conditions [9]. Suppose that an IP packet of average
length MI be fragmented in such a way that the resulting
MAC packets of variable length (due to link adaptation
modulation & coding decisions) Mmac contain a fixed
number of Mover header bits per packet [10]. In such a model
MI packet will be segmented into MI / Mmac total number of
RLC/MAC packets with MI MI / MmacMover total number
of transmitted bits. Considering non-ideal radio channel
conditions, in such a scenario, the transmission time needed
to completely transmit the IP packet will be increased due to
eventual retransmissions and non-scheduling periods of time.
It is important to remember that scheduler link adaptation
(LA) function will decide about non-scheduling periods and
MAC packet sizes based on Quality Class Identifier (QCI)
priorities and γ uplink measurements. The expected average
whole IP packet transmission time would be:
s
I mac
Mac
AP RB
overI
s s
T
M M
W m n
M M
T T
n n n
where nTs is the number of transmitted bits per RB
depending on Link Adaptation Modulation Scheme. nRB is
the average allocated number of 180 kHz RB blocks per Ts
transmission interval. nAP is the spatial multiplexing rank and
finally n and m are two integers indicating the average
number of Ts units of time one MAC packet is not scheduled
by scheduler and the average number of retransmissions one
packet should undergo due to channel conditions
respectively.
IV. CELL PLANNING ALGORITHM
In order to include the delay smart grid constraints into
the nominal cell planning procedure, design steps should be
considered introducing metrics to conclude average delay.
Substituting all these metrics into (6) the average scheduler
delay is estimated. Adding also the expected average
buffering delay the planners have an estimation of the
maximum expected radio delay for a service at cell edge.
Based on IEC 61850-5 [5] standards for Advanced Meter
Infrastructures smart grid applications planners could check
whether they are compliant with RDelay restriction, where
RDelay is the expected cell range due to delay constraints,
(Fig. 2). Following the analysis on nominal cell planning
with strict throughput constraints RThroughput [13] LTE cell
coverage range prediction for outdoor Urban coverage of
95% was roughly estimated to be d = 125 m. We should
follow explicitly the proposed steps for d = 125 m cell range
to validate our analysis on delay constraints. Cell Planning
analysis follows:
A. Path loss evaluation
Cell planners, during nominal cell planning, should
evaluate a cell range RThroughput that fulfills certain throughput
constraints. Following this assumption we could calculate
expected worst scenario pathloss Ltarget. Our analysis should
be based on certain defined pathloss models for LTE in
international literature. A well defined formula for 2.5 GHz
LTE microcell outdoor to outdoor coverage is [9]:
10
10
39 20log [ ] , 10 45
[ ]
39 67log [ ] , 45
d m m d m
L dB
d m d m
3. Fig. 2. IEC 61850-5 standards
Fig. 3. Absolute Inter-cell Interference
At worst radio conditions (cell edge user at d = 125 m)
[8] pathloss is calculated to be (7) -101.5 dB.
B. Noise floor per RB
Noise NRB per resource block is considered to be the
background wideband noise mostly created by Thermal
Noise Power Density in dB/Hz, calculated from Boltzmann’s
constant kB = 1.38 x 10-23
J/0
K and the absolute temperature
in Kelvin T = 290 0
K to be -174 dB/Hz and for 180 kHz
resource block bandwidth it is calculated as -111.44 dB, [13].
C. Uplink Interference per RB
Interference is considered to be inter-cell interference
from a neighbour cell UE transmitting on the same resource
block on same TTI. It could be calculated either from
mathematical assumptions [15], or simulation results or real
network measurements. From our perspective we do
consider that it is more accurate to have an average
estimation of inter cell interference per resource block at a
given path loss from real drive test measurements. During
drive test for 20 MHz band cell configurations, different
uplink received power levels Pr per RB have been reported
and the appropriate plots of Absolute Interference per RB vs.
cell edge Path Loss Ltarget have been created, Fig. 3. The
analytical mathematical functions after curve fitting are
expressed from up to bottom as:
2 3
2 3
2 3
2 3
480.631 9.850 0.08 0.0002
292.047 4.683 0.0372 0.000087
[ ]
264.84 3.832 0.03 0.000073
142.8 0.2315 0.002 0.00002
p p p
p p p
p p p
p p p
L L L
L L L
I dBm
L L L
L L L
At worst cell conditions we do suppose maximum UE
uplink power of PUE = 31.76 dBm = 1.5 W, an assumption
that is validated from most LTE handsets on market.
Considering typical cell bandwidth configuration of 20 MHz,
meaning 100 available number of physical resource blocks,
the available power per resource block is 1.5 W / 100 =
0,015 W = 11.76 dBm . Hence the expected received uplink
power per RB on the eNodeB antenna, considering a typical
Kathrein directional antenna gain of 18 dBi, will be Pr [dBm]
= PUE + GR – Ltarget = 11.76 dBm + 18 dBi – 101.5 = - 71.74
dBm. From (8) and figure 3 for Pr =< -100 dBm estimated
interference is considered to be IRB = -119.6 dBm.
D. Uplink γ estimation at cell edge
An adequate cell planning restriction is to select specific
SINR target γ0,target higher than expected eNB receiver
sensitivity. The eNB receiver sensitivity, SeNodeB, is defined
as the minimum uplink received power on base station
required to correctly decode uplink RB with 10-10
bit error
rate [13]:
0, arg[ ] eNodeB
eNodeB TPDF figure BW t etS dB N N RB
where TPDFN is the thermal noise power density,
calculated analytically from Statistical Physics Boltzmann’s
constant kB = 1.38 x 10-23
J/0
K and absolute temperature in
Kelvin T = 290 0
K , to be - 174 dB/Hz.
eNodeB
figureN is the
eNodeB noise figure which defines a degradation of SNR
due to RF components in an RF signal chain (2 dB for
uplink) [13,14] and RBBW is the resource block bandwidth of
180kHz .Substituting into (9) we get SeNodeB = -119.44 +
γ0,target dB. Considering a pre-selected link budget at cell edge
from (7), then a specific required SINR target could be
calculated as [13] and [15]:
,
arg ,
0, arg arg
[ ]
144.45
UE RB
t et T s eNodeB LNF BL
t et t et LNF BL
L dB P S M L
L M L
where MLNF is the log-normal fading margin, given by
Jakes formula, for 95% coverage calculated to be 6 dB for
Dense outdoor, 8.4 dB for Urban indoor or 10 dB for Dense
Urban Indoor [8]. LBL is body loss which could be considered
either as 2 dB for handset palm-top or 0 dB for lap-top [8].
Target γ0,target is considered extremely important since it will
4. Fig. 4. BER measurments, TU3 model
affect the decision upon selection of the number of resource
elements on uplink scheduling and MAC link adaptation
software module. Expected uplink γtarget at cell edge distance
(10) is estimated to be γtarget = 34.95 dB
E. Average number of uplink RB
Based on the target γ0,target on cell edge, the number of
allocated resource blocks nRB is calculated considering
uniform power distribution of nominal UE power PUE over
all transmitted resource blocks. This is an assumption which
is validated for most LTE handsets on the market [11].
Following basic link budget reasoning:
arg,
0, arg
0, arg
int
UE
received
t et RBUE RB
t et
RB RB
UE
RB
path RB RB t et
P
L nP
noise erference N I
P
ceiling n
L N I
The average number of uplink allocated RBs is estimated
to be ceiling[nRB] = 19, where ceiling[x] is the function
selecting the maximum integer number x from an analytical
calculation.
F. Transmitted bits per RB
Number of transmitted bits per RB nTs could be easily
calculated considering the worst case of cell edge UEs. In
such a case MAC scheduler [10], [14] will allocate QPSK
modulation (2 bits per symbol) with TX diversity, thus nAP =
1 in (6). One sub-frame contains 14 X 12 = 168 resource
elements (RE) and two OFMD symbols (24 RE) of the
subframe are allocated for sounding reference signals.
Available user plane bits per RB in (6) is considered to be
nTs = (168-24) x 2 = 288 bits/ ms.
G. MAC scheduling subframe intervals
During drive test on cell edge for 20 MHz bandwidth, an
FTP file of 3Mbyte = 24 Mbits was downloaded from an
intranet Teledrom AB server. Considering UE to be ideally
scheduled every subframe by MAC scheduler without
retransmissions, then according to the estimated number of
transmitted bits per RB on cell edge, nTs = 288 bits/ ms, the
expected max rate for cell edge user should be RB
n 288
kbps. Then minimum downloading time should be
24Mbits/( RB
n 288 kbps). From drive test the reported
average total downloading session service time, considering
non ideal conditions with initial transmissions,
retransmissions and non-scheduled periods, was estimated to
be 4.425 s. This means that the non-ideal contribution on
latency of retransmissions m and non-scheduled time periods
n is (m + n)Ts = (4.425 – 24Mbits/( RB
n 288 kbps)) s =
(4.425 – 24Mbits/(19 • 288 kbps)) s = 0,039 s.
H. Average number of HARQ MAC retransmissions m
The average number of retransmissions m is a function of
the physical packet error rate. Let p be the packet non
successful probability (error probability). Non successful
probability is related to the MAC packet length Mmac and the
bit error probability pb as [9]:
1 (1 ) macM
bp p
During nominal cell planning, γtarget and consequently bit
error probability pb have very low values, hence the average
number of retransmissions is approximated as [9]:
1
1 1 , 1
1
macM
b mac b bm p M p p
p
=
From (13) it is obvious that retransmissions depend
explicitly on the bit error probability pb and on the average
size of the MAC packet Mmac. To calculate pb most
researchers rely on simulations. In our paper instead we did
initiated drive test measurements in an urban environment
which is highly dispersive using a test e-NB of Teledrom AB
with a rooftop car antenna to remove car penetration losses.
Real data have been collected using TEMS investigation
Data Collection software and statistical counters have been
reported using Operation & Maintenance GUI Ericsson
tools. An LTE UE category 4 with typical characteristics of
max uplink bit rate = 50 Mbps, uplink higher supported
modulation 16 QAM with spatial multiplexing 22 or QPSK
with TX diversity has been used [11]. In Fig.4 BER vs.
blocking probability has been plotted. Test drive was
compliant with the Typical Urban channel model (TU3
model, 3Km/h) requirements [12]. Throughout the drive test
the average Eb/N0 has been reported to be equal to 30 dB,
indicating thus a relative good quality. From Fig. 4
Eb/N0 30dB corresponds to an approximate pb of 0.06.
5. Ericsson statistical counter pmUeThpVolUl in units of
[kbits] measures uplink MAC SDU volume and finally
Ericsson counter pmUeThpTimeUl in units [ms] provides
the period of MAC volume measurements in ms. From
TEMS investigation, during drive test, MAC reported
measurements have been calculated to be pmUeThpVolUl =
345282 kbits and pmUeThpTimeUl = 900000 ms = 900 sec
= 15 min. Hence pmUeThpVolUl/ pmUeThpTimeUl =
383.6 bits/1ms which provides average Mmac = 384 bits per
TTI interval of Ts = 1 ms. Substituting into (13) pb = 0,06
and Mmac = 384 bits results into average m = 24. Following
previous analysis (m + n)Ts = 0,039 s (24 + n) = 39 n
= 15.
I. Average MI and Mover estimation
Average MI and Mmac bits on (6) could be estimated from
drive test, following network statistics on Operation &
Maintenance SubSystem OSS for Ericsson test eNB on
Teledrom AB test equipment. Ericsson counter
PmPdcpVolUlDrb in units [kbits] measures total uplink
volume (PDCP Signaling Data Units SDU) in an established
Data Radio Bearer per measurement period, providing a
good estimate of MI. RLC/MAC overhead on LTE is
considered to be Mover = 20 bytes [15]. Following drive test
reported statistics PmPdcpVolUlDrb = 545627 kbits per
measurement period of 15 minutes = 900000 ms.
Consequently MI = PmPdcpVolUlDrb/900000ms= 607
bits/ms. Consequently MI / Mmac = 2. Overall delay in the
uplink transmission will be the contribution of MAC layer
delays (6) and PDCP buffer input delays (5). Substituting
previous analysis into (6) the final MAC delay will be:
42.22
607 2 160
39
288
s
I mac
Mac
AP RB
overI
s s
T
M M
W m n
ms ms ms
M M
T T
n n n
bits bits
Adding also (5) the worst case of a loaded handset service
of ρ = 0.8 then average buffer delay will be W = 6 ms,
contributing to total average delay of 42.22 ms + 6 ms =
48.22 ms. Following Fig. 2 it is obvious that, for all types of
smart grid signaling messages, outdoor LTE cell coverage
range of d = 125 m [8] fulfills delay constraints.
V. CONCLUSIONS
In general case planners should always reconsider the
cell range to minimize delay. To minimize delay, Wmac
should be minimized and from (14) it is obvious that the
highest contribution to MAC delay is produced by MAC
scheduler delay which is a function of Signal to Noise and
Interference ratio γ.
ACKNOWLEDGMENT
Authors would like to express their gratitude to P.
Kostopoulos, C.E.O. of Teledrom AB, Sweden, for its
prompt support on setting up LTE eNB for the Drive Test.
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