The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
In this paper, we address the problem of user scheduling in downlink coordinated multi-point transmission (CoMP) systems, where multiple users are selected and then served with zero forcing beamformer simultaneously by several cooperative base stations (BSs). To reduce the enormous overhead led by obtaining full channel state information at the transmitter, a low-feedback user scheduling method called...
The purpose of this paper is to reduce the complexity of scheduling scheme for OFDMA/SDMA system with multimedia traffic. To achieve this purpose, we propose a low-complexity beamforming-based scheduling (LCBS) scheme to solve the multi-dimensional (space, time, and frequency) radio resource allocation problem in OFDMA/SDMA systems. By utilizing a semi-orthogonal user selection (SUS) algorithm, the...
With the advent of new applications, one of the primary applications supported in downlink cellular systems is streaming video. QoS for streaming video entails data transmission to the mobile stations with limited latency and limited jitter. This requirement on latency and jitter can be mapped to the number of yet-to-be-played packets in a mobile station's buffer, to always be above a certain minimum...
Previous work has proposed the Dynamic Switch Buffer Management (DSBM) scheme, a promising approach for improving the scalability of switch ingress memories. In this paper, we extend these results by adding increased backlog awareness into the latter. In particular, we propose using a novel combination of two backlog-aware algorithms: BA-DSBM to map incoming packets to the switch's ingress buffers...
An important issue of supporting multi-user video streaming over wireless networks is how to optimize the systematic scheduling by intelligently utilizing the available network resources while, at the same time, to meet each video's QoS (quality of service) requirement. In this work, we study the problem of video scheduling over multi-channel multi-radio multi-hop networks with the goals of minimizing...
IEEE 802.22 wireless regional area network (WRAN) is an emerging cognitive radio-based system. One of the major challenges for WRANs is how to efficiently schedule both channel sensing and data transmission for multiple adjacent WRAN cells. This challenge is known as coexistence problem. In this paper, we propose four schemes that aim at reducing the coexistence-problem effect. These schemes are based...
In wireless networks, mutual interference prevents wireless devices from correctly receiving packages from others and becomes one of the challenges in the design of protocols for wireless networks. Spatial-reuse time division multiple access (STDMA) has been used to cope with this problem. In this scheme, links are assigned to several time slots and in each slot all the links can transmit simultaneously...
We consider a slotted input-queued switch with a crossbar-like switching fabric. In each time-slot, a centralized scheduler determines a switching fabric configuration to transfer packets. We consider the energy consumption needed to configure the switching fabric and we assume that the energy depends on the number of modifications in the switching configuration in two consecutive time-slots. We address...
The communication between a multiple-antenna transmitter and multiple receivers (users) with either a single or multiple-antenna each can be significantly enhanced by providing the channel state information at the transmitter (CSIT) of the users, as this allows for scheduling, beamforming and multiuser multiplexing gains. The traditional view on how to enable CSIT has been as follows so far: In time-division...
This paper proposes a spatial time-division multiple access (STDMA) throughput enhancement scheme for a multiGbps millimeter-wave (mmWave) wireless personal area network (WPAN) system. The system design includes in the medium access control (MAC) layer, an interference-monitoring mechanism and a heuristic TDMA time-slot scheduling engine, and in the physical (PHY) layer, a Reed-Solomon (RS) coded...
Traditional crossbar switches use centralized scheduling algorithms with high time complexity. In contrast, buffered crossbar switches are capable of distributed scheduling due to crosspoint buffers, which decouple the dependency between inputs and outputs. However, crosspoint buffers are expensive on-chip memories. To reduce the hardware cost of buffered crossbar switches and make them scalable,...
Wireless Mesh Networks (WMNs) is a promising key technology for next generation wireless backhauling that is expected to support various types of applications with different quality-of-service (QoS) demands. Advanced antenna techniques, novel scheduling algorithms and routing schemes have attracted increased research interests aiming to optimize the performance of WMNs and satisfy their vast and diverse...
Data aggregation is a primitive communication task in wireless sensor networks (WSNs). In this paper, we study designing data aggregation schedules under the Protocol Interference Model for answering queries. Given a network consisting of a set of nodes V distributed in a two-dimensional plane, we address different kinds of queries in this paper. First and foremost, we consider a single one-off query...
We consider the problem of minimum-length scheduling of point-to-point links in a spatial TDMA (STDMA) based wireless network with Rayleigh fading of both desired and interference signals. The problem formulation integrates the activation of multiple sets of links in the network, while taking into account their explicit statistical variations. We assume uniform (fixed) transmission power at all nodes...
The majority of vehicle-to-vehicle (V2V) protocols presented in the literature utilize a combination of controlled access techniques (e.g., TDMA, FDMA, CDMA) to provide prioritized access to the communication medium. While these protocols split the capacity of the communication link to support a maximum number of users with different priority levels, our work utilizes a combination of CDMA and TDMA...
This paper deals with two fundamental joint routing and scheduling problems in multi-hop wireless mesh networks (WMNs) employing time division multiple access (TDMA). The problems pertain to incremental update of schedules as some of the existing flows terminate and new flow demands are received. In the first problem, referred to as single flow scheduling (SFS) problem, we are given a set of ongoing...
In this paper, we consider joint end-to-end congestion control and multiuser scheduling in multi-hop wireless networks, where orthogonal frequency-division multiple access (OFDMA) is the air interface. Compared to its single-channel counterpart, this problem is significantly more challenging because subchannel assignment and power allocation for all nodes and network traffic need to be jointly optimized...
We consider a set of multicast sources, each multicasting a finite amount of data to its corresponding destinations. The objective is to minimize the time to deliver all traffic, i.e., to obtain schedules of minimum length. We consider time-varying wireless networks with imperfect side information at the sources. We model the minimum-length scheduling problem through partially observable stochastic...
Cognitive radio technology is widely accepted as an efficient approach to solve the problem that the wireless spectrum has been getting scarcer and scarcer due to the rapid growth in the ubiquitous wireless applications. Several cognitive medium access control (MAC) protocols have been proposed for the secondary users (non-licensed users) to take advantage of the vacant channels whenever they are...
Available network information is an important factor in determining network performance. In this paper, we study the basic limits on the amount of network information that should be transmitted in the network to achieve a given level of network performance. From the perspective of information theory, network information is an information source, and the lower bound on network information is the minimum...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.