ofdma

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QoS Provisioning and Radio Resource Allocation in OFDMA Based WiMAX Systems

Broadband Wireless Access based on the IEEE 802.16 suite of standards is quickly gaining importance as the basis for 4G technology, with the capability of providing high data rate QoS provisioned services for static as well as highly mobile users. Amongst the different PHY layers in the specification, Orthogonal Frequency...

Tags: QoS, Rensselaer Polytechnic Institute, Radio, Allocation, OFDMA, WiMAX, Wireless And Mobility

White papers 2009-01-01

WiMAX Downlink OFDMA Burst Placement for Optimized Receiver Duty-Cycling

Mobile wireless broadband access networks are now becoming a reality, thanks to the emerging IEEE 802.16e standard. This kind of network offers different challenges when compared to the fixed ones, as power consumption becomes a major concern. In this standard, a strict organization of the downlink bursts is not guaranteed...

Tags: WiMAX, IEEE, Burst, OFDMA, Wireless And Mobility

White papers 2008-10-16

Adaptive TUF Packet Scheduling Scheme for OFDMA-Based WiMAX Systems

WiMAX is a well-known broadband wireless access technology to support for different users in multimedia transmission. Its physical layer can be employed with Orthogonal Frequency-Division Multiple Access OFDMA technology. IEEE 802.16e has evolved five scheduling types of Quality of Service QoS for uplink transmission, but has not yet clearly defined...

Tags: QoS, Broadband Wireless, OFDMA, Asia University, WiMAX, Broadband Internet, Wireless And Mobility, Telecommunications, Wi-Fi

White papers 2008-09-20

Deploying Mobile WiMAX Networks

WiMAX, the Worldwide Interoperability for Microwave Access, is described by the WiMAX Forum as "A standards-based technology enabling the delivery of last mile wireless broadband access as an alternative to cable and DSL". WiMAX is designed to provide wireless service with higher data rate, longer range, more efficient use of...

Tags: Mobile, OFDMA, Berkeley Varitronics Systems, BVS YellowFin WiMAX Analyzer, WiMAX, Wi-Fi, Wireless And Mobility

White papers 2008-06-13

Multi-User Frequency Domain Scheduling for WiMAX OFDMA

This paper introduces the performance analysis of 802.16e OFDMA system in UL mode with respect to multi-user scheduling algorithms in frequency domain. Different scheduling algorithms - from the simplest round robin to the optimal iterative scheduling, along with practical maximum element and two-step algorithms are analyzed and compared. It is...

Tags: Algorithm, WiMAX, Domain, OFDMA, Imperial College London, Frequency Domain, Engineering

White papers 2007-08-29

WiMAX and IMT-2000

The inclusion of mobile WiMAX under the IMT-2000 umbrella will offer significant benefits to the mobile community by assuring the global delivery of Wireless Broadband Internet services at the lowest cost. Mobile WiMAX is based upon Orthogonal Frequency Division Multiple Access OFDMA, an access technology standardized in the IEEE 802.16e-2005...

Tags: Mobile, OFDMA, OFDMA Technology, WiMAX, Wi-Fi, Advertising & Promotion, Wireless And Mobility, Marketing

White papers 2007-01-22

Joint Congestion Control and OFDMA Scheduling for Hybrid Wireline-Wireless Networks

This paper considers joint congestion control and multiuser scheduling in a hybrid wireline and wireless network, where the air interface of wireless links is based on Orthogonal Frequency Division Multiplexing OFDM. For static channels, the paper formulates this cross-layer design as a Network Utility Maximization NUM problem with both wireline...

Tags: Congestion Control, Wireless Link, University Of Minnesota, OFDMA, OFDM, Wi-Fi, Wireless

White papers 2006-12-13

Optimal Scheduling for OFDMA Systems

This paper considers a scheduling and resource allocation problem for the downlink of an OFDMA-based wireless network, where the channel estimation error is modeled by a self-noise term in the decoding process. During each time-slot this involves selecting a subset of users for transmission, determining the assignment of available subcarriers...

Tags: Algorithm, Princeton University, OFDMA, Engineering

White papers 2006-11-24

Will Aussie patents turn Wi-Fi into a house of cards?

Will Aussie patents turn Wi-Fi into a house of cards?WiMax uses OFDMAWiMax also uses Orthogonal Frequency Division Multiple Access technologyhttp://www.intel.com/netcomms/technologies/wimax/OFDMA and OFDMMobile WiMax (802.16-2005)'s OFDMA has a fair amount in common with OFDM, in terms of subdividing frequencies ranges into subchannels, each of which can carry independent data stream. With...

Tags: government, Wi-Fi, OFDMA, OFDM

Discussion threads 2006-11-21

Delay Analysis and Comparison of OFDM-TDMA and OFDMA Under IEEE 802.16 QoS Framework

The delay analysis and comparison of OFDM-TDMA and OFDMA using a flow control scheme under the QoS framework of IEEE 802.16 are conducted in the work discussed in this paper. The paper investigates the maximum packet delay performance by deriving delay bounds for several multiaccess modes with different subcarrier/time-slot assignment...

Tags: University Of Southern California, Performance, Allocation, IEEE 802.16, Scheme, Analysis, OFDMA, WiMAX, Performance Management, Wireless, Human Resources, Workforce Management

White papers 2006-07-22

Comparison and Cost Analysis of Smart and Opportunistic MIMO OFDM Schemes

This paper attempts to compare the system downlink performance of a smart antenna scheme for OFDMA that utilizes channel covariance information with an opportunistic multi-antenna scheme for OFDMA that uses fast limited feedback of the instantaneous channel condition. The schemes are evaluated by means of simulations in a low load...

Tags: Scheme, Analysis, OFDMA, Antenna Method, Performance Management, Human Resources, Workforce Management

White papers 2006-02-10

Performance Analysis of a Reuse Partitioning Technique for OFDM Based Evolved UTRA

The current 3GPP working assumption on the Evolved Universal Terrestrial Radio Access (E-UTRA) physical layer is that it will be based on Single Carrier Frequency Division Multiple Access (SC-FDMA) for the uplink and Orthogonal Frequency Division Multiple Access OFDMA for the downlink. According to the concept specification, inter-cell interference mitigation...

Tags: Technique, Performance, OFDMA, OFDM, Productivity

White papers 2006-02-01

Resource Allocation in OFDMA Wireless Networks With Time-Varying Arrivals

This paper considers the issue of optimal subcarrier allocation in OFDMA wireless networks when the arrivals and channels are stochastic and time-varying. The objective is to minimize the long-term average packet delay over multiple time epochs. This paper shows by example that water-filling-based subcarrier allocation policy which maximizes throughput at...

Tags: Allocation, OFDMA

White papers 2005-11-14

MC-CDMA Versus OFDMA in Cellular Environments

In this paper, two candidates for a next generation (4G) downlink system in a multi-cell environment are studied in respect to their error performance. The paper investigates on the one hand, an Orthogonal Frequency Division Multiplexing OFDM based Multiple Access scheme OFDMA, and on the other hand, a Multi-Carrier Code...

Tags: Environment, OFDMA, German Aerospace Center

White papers 2005-04-14

Innovations in Wireless Broadband Technologies

This paper presents innovations related to the use of OFDM/OFDMA in IEEE 802.16 as well as ETSI HiperMAN standards. The paper addresses the last innovations in standards, related to channel estimation in high delay-spread environments, carrier allocation for optimal cell range extension and better frequency reuse when using OFDMA, SNR...

Tags: Innovation, Alvarion Ltd., Broadband, OFDMA, Wireless Broadband, Leadership, OFDM, Strategy, Wireless, Management

White papers 2004-12-08

Rate Stable Resource Allocation in OFDM Systems: From Water-Filling to Queue-Balancing

This paper considers the issue of optimal subcarrier allocation in OFDMA. The authors show, via a counter example, that water-filling based subcarrier allocation policies, contrary to conventional wisdom, fail to provide rate-stability for an otherwise stabilizable OFDMA system. Water-filling is too myopic when considering longtime average performance, e.g. delay, queue...

Tags: Allocation, OFDMA, OFDM

White papers 2004-12-05

A Fresh Look at Optimal Subcarrier Allocation in OFDMA Systems

This paper considers the issue of optimal subcarrier allocation in OFDMA. This paper shows, via a counter example, that water-filling based subcarrier allocation policies, contrary to conventional wisdom, fail to provide rate-stability for an otherwise stabilizable OFDMA system. Water-filling is too myopic when considering long-time average performance, e.g. delay, queue...

Tags: Allocation, OFDMA

White papers 2004-09-09

Capacity Analysis on Downlink MIMO OFDMA Systems

Motivated by the increasing popularity of OFDMA and MIMO, this paper studies the capacity of MIMO enabled OFDMA system under a generic multiuser multicarrier framework. This paper shows that in terms of total system capacity, OFDMA is the optimal downlink scheme for independent decoding receivers. To achieve the capacity bound...

Tags: Allocation, Analysis, OFDMA

White papers 2004-08-24

Scalable OFDMA Physical Layer in IEEE 802.16 WirelessMAN

The concept of scalability was introduced to the IEEE 802.16 WirelessMAN Orthogonal Frequency Division Multiplexing Access OFDMA mode by the 802.16 Task Group e TGe. A scalable physical layer enables standard-based solutions to deliver optimum performance in channel bandwidths ranging from 1.25 MHz to 20 MHz with fixed subcarrier spacing...

Tags: IEEE 802.16, OFDMA, WiMAX, Wireless

White papers 2004-08-20

IEEE 802.16 Medium Access Control and Service Provisioning

This paper describes the IEEE 802.16 Orthogonal Frequency Division Multiplexing OFDM and the 802.16 Orthogonal Frequency Division Multiple Access OFDMA, Medium Access Control MAC protocols, both of which are key elements of the Worldwide Interoperability for Microwave Access Forum WiMAX deployments. The paper also discusses the types of provisioning and...

Tags: IEEE 802.16, Service Provisioning, OFDMA, WiMAX, Wireless And Mobility, Wi-Fi

White papers 2004-08-20