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Date 3-4 May 2011

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Displaying Results 1 - 25 of 55
  • Congestion awareness in tactical wireless networks: Discerning congestion-induced losses from wireless link effects

    Publication Year: 2011 , Page(s): 1 - 6
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (263 KB) |  | HTML iconHTML  

    Efficient congestion detection represents an unsolved challenge for tactical networks. This paper presents an edge-based packet probing technique to detect congestion that incurs modest control overhead. The approach presented, herein, is “Differential Performance Packet Probing” (DP3) and leverages the differential treatment of packets at the queues of routers and radios. By measuring loss rates across different types of probe packets, DP3 can detect congestion events and, furthermore, distinguish packet losses due to path congestion events from losses due to link outage events. Extensive results are reported for lab experiments of the DP3 concept in an emulated wireless network environment and in a wired Cisco environment. Detailed statistical analysis of the tradeoff between reliability and agility of the DP3 congestion indicator is also described. View full abstract»

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  • Skip-ahead routing in wireless networks

    Publication Year: 2011 , Page(s): 1 - 5
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (110 KB) |  | HTML iconHTML  

    Exploiting the broadcast nature of wireless channels, transmitted packets “skip ahead” to receiving nodes farther downstream along an existing, established mesh routing path. Packets are thereby able to more quickly advance through a mesh network towards their destination. This occurs on a packet-by-packet basis and is advantageous even if the underlying path (at that moment) has been optimized. Analysis demonstrates improvements of 25% and greater (as a function of key network parameters), which translates into lower end-to-end latency and possibly higher network throughput. View full abstract»

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  • Designing energy-efficient optical line terminal for TDM passive optical networks

    Publication Year: 2011 , Page(s): 1 - 5
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (355 KB) |  | HTML iconHTML  

    This paper proposes a novel scheme which can efficiently reduce the energy consumption of Optical Line Terminals (OLTs) in Time Division Multiplexing (TDM) Passive Optical Networks (PONs) such as EPON and GPON. Currently, OLTs consume a significant amount of energy in PON, which is one of the major FTTx technologies. To be environmental friendly, it is desirable to reduce energy consumption of OLT as much as possible; such requirement becomes even more urgent as OLT keeps increasing its provisioning data rate, and higher data rate provisioning usually implies larger energy consumption. In this paper, we propose a novel energy-efficient OLT structure which guarantees services of end users with the smallest number of power-on OLT line cards. More specifically, we adapt the number of power-on OLT line cards to the real-time incoming traffic. Also, in order to avoid service disruption resulted by powering off OLT line cards, proper optical switches are equipped in OLT to dynamically configure the communications between OLT line cards and ONUs. View full abstract»

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  • Non-blocking memory-memory-memory Clos-network packet switch

    Publication Year: 2011 , Page(s): 1 - 5
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (178 KB) |  | HTML iconHTML  

    Buffered Clos-network switch, also referred as memory-memory-memory (MMM) Clos-network switch, is an alternative to single-stage switches to implement large-scale packet switches. In this paper, we unveil the head-of-line blocking problem of MMM Clos-network switches with switch modules implemented by buffered crossbars, which causes performance degradation. We propose a three-stage buffered Clos-network switch with per-output flow queues in the switch modules at the first two stages to avoid head-of-line blocking. The proposed switch, called the MMeM switch, achieves higher performance than an MMM buffered Clos-network packet switch. We show the performance improvement of the proposed MMeM switch under different traffic patterns. View full abstract»

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  • A study in photonic switched networks considering link failure and ingress buffering

    Publication Year: 2011 , Page(s): 1 - 5
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (267 KB) |  | HTML iconHTML  

    In this paper we study the behavior of traffic in Metropolitan Access Optical Networks with technologies of optical packet/burst switching (OPS/OBS), using computer modeling and simulations. We analyze network performance and the impact of link failure when electronic buffering at ingress (client input) to optical network is implemented. Mesh and ring topologies are chosen and parameters packet loss fraction and average number of hops are adopted for performance metrics. The use of minimum electronic buffering at ingress is demonstrated to improve access to the optical layer, and necessary to keep the packet loss fraction low and throughput high with low latency. We also show that optical buffering is not necessary for adequate network performance. View full abstract»

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  • Impact of MAI on the performance of WDM/OCDM OBS networks using 2D wavelength-hopping and time spreading optical codes

    Publication Year: 2011 , Page(s): 1 - 5
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (292 KB) |  | HTML iconHTML  

    The performance of an WDM/OCDM switch architecture is investigated under impairment of Multiple Access Interference (MAI). Analytical models are employed to evaluate the switch resources, such as the number of optical codes carried on each wavelength. In addition, the performance of Sparse Partial Optical Code Conversion (SPOCC) architecture is investigated using a hybrid technology, in Optical Burst Switching (OBS) networks, which employ wavelength and optical code division multiplexing. The simulation results indicate that both the increase of the number of optical codes per wavelength and the utilization SPOCC architecture, leads to considerable decrease of the Burst Blocking Probability (BBP). In addition, such hybrid approach also improves the utilization of network resources. View full abstract»

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  • Game theory based bio-inspired techniques for self-positioning autonomous MANET nodes

    Publication Year: 2011 , Page(s): 1 - 5
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (157 KB) |  | HTML iconHTML  

    In this paper, we introduce a new node spreading bio-inspired game (NSBG) combining bio-inspired algorithms and traditional game theory to maximize the area covered by autonomous mobile ad hoc network nodes and to achieve a uniform node distribution while keeping the network connected. NSBG is a distributed and scalable game where each node's selfish actions lead the entire network toward a uniform and stable node distribution without a centralized controller. In NSBG, each mobile node autonomously makes movement decisions based on localized data while the movement probabilities of possible next locations are assigned by a force-based genetic algorithm (FGA). Because FGA takes only into account the current position of the neighboring nodes, our NSBG, combining FGA with traditional and evolutionary game theory, can find even better locations by setting up spatial games among neighbors. NSBG is a good candidate for the node spreading class of applications used in both military and commercial applications. We present a formal analysis of our NSBG to prove that an evolutionary stable state is its convergence point. Simulation experiments demonstrate that NSBG performs well with respect to network area coverage, uniform distribution of mobile nodes, and convergence speed. View full abstract»

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  • Ant Colony Optimization approach to interference minimizing code assignment in cognitive CDMA networks

    Publication Year: 2011 , Page(s): 1 - 5
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (151 KB) |  | HTML iconHTML  

    In this paper we focus on the problem of code assignment to cognitive users in a synchronous underlay network using Code Division Multiple Access (CDMA) scheme. No knowledge of the spreading codes used by the primary CDMA network is available to the cooperative secondary users a priori, other than the spreading factor. An evolutionary algorithm of relatively low complexity order is proposed based on Ant Colony Optimization (ACO) for assigning spreading codes to secondary users such that the mutual interference between existing secondary and primary users is minimized. This is accomplished at the secondary fusion center by minimizing the mean square cross-correlation between the candidate codes and the matrix which includes all independently received signals by the cooperative secondary users. Simulation results show that performance of the ACO-based method can converge to the optimal interference minimizing code assignment method while the complexity order is significantly reduced. View full abstract»

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  • Power efficient coded 16-OQAM schemes over nonlinear transmitters

    Publication Year: 2011 , Page(s): 1 - 6
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (180 KB) |  | HTML iconHTML  

    High power and spectral efficiencies are crucial on modern wireless communications. M-QAM (Quadrature Amplitude Modulation) modulations have been adopted on HSDPA (High Speed Downlink Packet Access) and satellite links, due his higher spectral efficiency. However, due to large envelope fluctuations levels, nonlinear operations such as an high power amplification are undesirable since can they lead to performance degradation and spectral widening. Nonlinearly coded M-OQAM (Offset Quadrature Amplitude Modulation) modulations can be viewed as a particular case of nonlinear OQPSK signals (Offset Quadrature Phase Shift Keying) when the pulse modulation is designed to take advantage from the nonlinear format. In this paper we present nonlinearly encoded 16-OQAM schemes, based on two nonlinear OQPSK signals, designed to allow higher amplification efficiencies due its robustness against nonlinear distortions. The proposed approach assures an higher robustness against nonlinear effects, namely spectral regrowth and performance degradation. The consequences are improved performances over several drive operations of nonlinear amplifiers and a better compromise between bandwidth and power efficiencies. As we can see further the posted simulation results support our assumptions. View full abstract»

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  • Formal convergence analysis for bio-inspired topology control in MANETs

    Publication Year: 2011 , Page(s): 1 - 5
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (397 KB) |  | HTML iconHTML  

    We present a convergence analysis of a genetic algorithm based topological control mechanism for the decision making process of evolutionary and autonomous systems that adaptively reconfigures spatial configuration in mobile ad hoc networks (MANETs). Mobile nodes adjust their speed and direction using information collected from the local neighborhood environment in unknown geography. We extend the stochastic model of the genetic operators (i.e., selection, crossover and mutation) called the dynamical system model that represents the behavior of a single node's decision mechanism in the network viewed as a stochastic variable. We introduce an ergodic homogeneous Markov chain to analyze the convergent nature of multiple mobile nodes running our algorithm, called the Force-based Genetic Algorithm (FGA). Here, a state represents an instantaneous spatial configuration of nodes in a MANET. It is shown that the Markov chain model of our FGA is ergodic and its convergence is shown using Dobrushin's contraction coefficients. It is observed that scenarios where nodes have small communication ranges compared to their movement range converge quicker than larger ones due the limited information they have of their neighborhood, making movement decisions simpler, thus conserving energy. View full abstract»

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  • Generalised link-layer adaptation with costly power under higher-layer criteria

    Publication Year: 2011 , Page(s): 1 - 5
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (121 KB) |  | HTML iconHTML  

    It has long been recognised that a wireless communication system can be more efficient if link-layer parameters such as modulation order, symbol rate and packet size, are (adaptively) optimised. A common optimising criterion is to maximise spectral efficiency (bits per second per Hertz (bps/Hertz)) subject to a very low bit-error constraint. But a packet-oriented criterion for link adaptation seems more appropriate for practical communication networks fitted with strong error detection and a selective packet re-transmission mechanism. In recent work, we performed link optimisation for maximal bits per second or bits per Joule for data (delay-tolerant) traffic. In the present work, we extend our previous analysis to consider the case of costly power. The cost can be interpreted in the common economic sense, or can be a signal to encourage efficient resource use in a decentralised matter; furthermore, it may simply be a “Lagrange multiplier” in a centralised optimisation. When the symbol rate is flexible, the result under pricing is similar to the costless scenario: a set of possible link configurations can be ranked by the slope of a tangent line from the origin to the graph of a scaled version of the PSRF: the steeper the tangent the better the configuration. However, if the “effective price” - the power price divided by the noise-normalised channel gain - is sufficiently high, it is optimal for the terminal not to operate. If the symbol rate is fixed, the optimal configuration depends on the effective price. View full abstract»

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  • System design and network architecture for a millimeter-wave mobile broadband (MMB) system

    Publication Year: 2011 , Page(s): 1 - 6
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (330 KB) |  | HTML iconHTML  

    Evolution beyond 4G (LTE and mobile WiMAX) is crucial in keeping up with the exponential growth of mobile data traffic. In this paper, we describe a millimeter-wave mobile broadband (MMB) system that utilizes frequencies in the 3-300 GHz spectrum as a candidate for next generation mobile communication. A few key concepts in MMB network architecture such as the MMB inter-BS backhaul link, MMB base station grid, and hybrid MMB + 4G system are described. We demonstrate the feasibility of using millimeter waves to provide Giga bps data rate at a distance up to 1 km for mobility up to 350 kmph. We also discuss a few aspects of MMB air interface design such as beamforming, multiple access, and adaptive modulation and coding. View full abstract»

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  • High efficiency digital polar transmitter for cellular handsets

    Publication Year: 2011 , Page(s): 1 - 5
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (98 KB) |  | HTML iconHTML  

    In this paper, the architecture of a digital polar transmitter system for cellular multi-mode handset is presented with hardware implementation emphasis on 2/2.5G systems (GSM/EDGE). The most prominent feature of this architecture is it's ability to employ a highly nonlinear PA, this highly efficient. This is accomplished via our novel real-time nonlinear closed-loop predictive calibration for correcting the PA's nonlinearity. In addition, our architecture makes it possible to eliminate or minimize the need for extensive factory calibration since our predictive realtime auto-calibration scheme does not require much prior knowledge of the system characteristics. View full abstract»

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  • A 19–26 GHz balanced amplifier in 130 nm CMOS technology

    Publication Year: 2011 , Page(s): 1 - 5
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (330 KB) |  | HTML iconHTML  

    The design of a fully integrated balanced amplifier implemented in a 130 nm CMOS technology is described in this paper. This balanced amplifier achieves a gain of 30 dB from 19 GHz to 26 GHz. To reduce the signal loss and the physical dimensions of the 90° coupler utilized in this balanced amplifier, a meandered broadside coupler with shield is designed. This on-chip 90° coupler occupies a compact area of 300 um × 120 um. An effective technique based on tuning the width of the transistors to achieve wideband operation is also proposed in this paper. The proposed balanced amplifier design achieves an IIP3 of -6.0 dBm and an input 1-dB gain compression point of -16.5 dBm. The OIP3 and the output 1-dB gain compression point are 24.0 dBm and 10.7 dBm, respectively. View full abstract»

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  • Bit error rate analysis of digital communications signal demodulation using wavelet denoising

    Publication Year: 2011 , Page(s): 1 - 6
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (403 KB) |  | HTML iconHTML  

    Communications receiver performance obtained in conjunction with de-noising of digitally modulated communications signals using wavelet signal processing is described in this paper. The study includes both simulation results and the analytical characterization of the bit error rate (BER) performance obtained for BPSK and QPSK modulation schemes. The digital communications system consists of an MPSK modulator, an additive White Gaussian noise channel, and a receiver that employs a wavelet de-noising operation followed by a matched filter detector. Overall system performance for each modulation type considered is described by means of BER curves over a range of Eb/N0 values. It has been found that the significant improvement in BER compared to systems wherein the matched filter detector is not preceded by a wavelet de-noising operation is due to the effective increase in pre-detection signal-to-noise ratio (SNR). Statistical analysis of the de-noised modulated signals is presented. The corresponding analytical evaluation of BER for receivers using wavelet de-noising is derived. View full abstract»

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  • An automatic volume control for preserving intelligibility

    Publication Year: 2011 , Page(s): 1 - 5
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (260 KB) |  | HTML iconHTML  

    A new method has been developed to adjust volume automatically on all audio devices equipped with at least one microphone, including mobile phones, personal media players, headsets, and car radios, that might be used in noisy environments, such as crowds, cars, and outdoors. The method uses a patented set of algorithms, implemented on the chips in such devices, to preserve constant intelligibility of speech in noisy environments, rather than constant signal-to-noise ratio. The algorithms analyze the noise background in real time and compensate only for fluctuating noise in the frequency domain and the time domain that interferes with intelligibility of speech. Advantages of this method of controlling volume include: Controlling volume without sacrificing clarity; adjusting only for persistent speech-interference noise; smoothing volume fluctuations; and eliminating static-like bursts caused by noise spikes. Practical human-factors approaches to implementing these algorithms in mobile phones are discussed. View full abstract»

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  • Advanced diagnostic system with ventilation on demand for underground mines

    Publication Year: 2011 , Page(s): 1 - 6
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (288 KB) |  | HTML iconHTML  

    After a series of recent world wide mine tragedies, ranging from collapsing mines in China and Colombia to trapped miners in Chile, the importance of robust and reliable underground communication networks has become evident once again. A reliable underground communication network in mines will not only facilitate the day to day operations but will also help save many lives. However, designing reliable and robust underground network has always been a challenge due to the special nature of mines. These extreme and harsh mine conditions require special communication systems like leaky feeders, Through The Earth (TTE), and wireless mesh networks. While TTE is used in case of disaster recovery and locating trapped miners and wireless mesh is used for sensing the mine conditions, the leaky feeder system can be considered the most popular communication system used for daily operations. It carries voice, video, and data; however, the leaky feeder system is not reliable and problems are hard to diagnose. This paper describes a novel advanced diagnostic system with a ventilation on demand capability that enhances leaky feeders; this system will not only allow monitoring of all underground nodes connected to the leaky feeder. It will also allow remote programming from the control room above ground and monitoring the losses in the leaky feeder in the sense that the infrastructure will be able to monitor itself. Ventilation on demand is another advantage of this system as it will operate the underground mine ventilation fans depending on data collected from sensors attached to the leaky feeder. This will provide huge power savings since ventilation fans are responsible for about 60% of power consumption in mines. The system is described here along with simulation results proving its performance. View full abstract»

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  • Survey on an efficient, low-complex tuple search based sphere detector

    Publication Year: 2011 , Page(s): 1 - 6
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (213 KB) |  | HTML iconHTML  

    Nowadays, high detection complexity is known to be one of the major challenges in MIMO communications based on spatial multiplexing. Tuple search (TS) sphere detection was recently introduced, demonstrating to represent a promising approach in this context. It provides significant complexity reduction in comparison to conventional algorithms, providing in addition close to full max-log-APP BER performance. Due to the increasing multiplicity of communication standards as well as variety of mobile applications demanded by users, tackling the lack of flexibility of common receiver realizations has become an additional key challenge in MIMO detection. Aim of this work is to demonstrate that the benefit provided by the tuple search strategy is still present in a wide range of possible transmission schemes. For this purpose, a novel efficiency indicator is introduced, based on which an exhaustive analysis is performed. The existing tuple search detector has been adapted to deal with different constellation orders and transmit/receive antenna configurations. In addition, the applied MMSE strategy has been modified to support undetermined systems. The obtained results show the superiority of the proposed sphere detector under different transmission conditions, thus demonstrating its efficiency and flexibility. View full abstract»

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  • MSOM based automatic modulation recognition and demodulation

    Publication Year: 2011 , Page(s): 1 - 5
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (116 KB) |  | HTML iconHTML  

    Automatic modulation recognition (AMR) and demodulation are two essential components in cognitive radio receivers. This paper proposes a novel method based on MSOM neural networks to automatically recognize the modulation type and demodulate the radio signal at the same time. This efficient method is directly applied to the normalized radio signal samples and has relatively low computation complexity. A dynamic AMR method is also introduced, which further can reduce the computation without obvious loss in recognition. In this paper, four modulation types, i.e. BPSK, MSK, 2FSK and QPSK, are investigated. Our simulation results show that, compared with the traditional cyclic feature-based methods, the proposed MSOM classifier has better performance while requiring less number of signal samples, and it can also perform demodulation at good accuracy. View full abstract»

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  • Ensuring voters and candidates' confidentiality in E-voting systems

    Publication Year: 2011 , Page(s): 1 - 6
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (112 KB) |  | HTML iconHTML  

    A new method based on cryptography to ensure voters and candidates' confidentiality in the Internet E-Voting, referred to as the Name and vOte separaTed E-voting (NOTE) system, is proposed. In NOTE, an impartial party, the Election Commission (EC) will be responsible for part of the vote counting duties besides collecting and verifying the voter ID. The votes and the candidates' names are separated into two parts during the counting process. EC will hold the candidates' names secret before the tally comes up; the Vote Counting Committee (VCC) only counts the votes and is not involved in unveiling the vote tally by virtue of the anonymity of the candidates. Only EC can disclose the final tally after VCC has counted all votes without knowing who the votes are for during the vote counting procedure. This scheme will effectively ensure voters and candidates' confidentiality, and thus improving election security and fairness. View full abstract»

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  • Ubiquity and integration in m-Health: Implications for brand management

    Publication Year: 2011 , Page(s): 1 - 6
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (162 KB) |  | HTML iconHTML  

    The purpose of this paper is to discuss the widespread changes impacting consumers and business in the e-Landscape, with a focus upon the idea that market pull is resulting in demand for m-Health, which encompasses mobile health related devices and applications that enable consumers to manage healthcare anywhere, anytime and with security. The e-Landscape model is reviewed and implementation issues are broached by exploring the notions of the value proposition and value chain networks. The value proposition is regarded as a central organizing principle around which a business can be configured. This enables managers to align changing customer needs, resources, internal relationships and external partnerships, to deliver the brand promise to the marketplace. View full abstract»

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  • UE centric coordinated beamforming in multi-cell MU-MIMO systems

    Publication Year: 2011 , Page(s): 1 - 6
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (148 KB) |  | HTML iconHTML  

    User Equipment (UE) centric coordinated beamforming (CBF) is an enabling technology in multi-cell MU-MIMO systems. It is of great importance to know the suggested cooperating set size for CBF and the corresponding performance. In this paper, a novel joint space-time-frequency proportionally fair scheduler for CBF is proposed to provide a tradeoff between the average system performance and UE fairness. The impact of the cooperating set size on system performance is predicted through the analysis of a simplified system, and then confirmed through numerical results of the whole system using the proposed scheduler. View full abstract»

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  • Efficient decoding methods in MIMO systems

    Publication Year: 2011 , Page(s): 1 - 6
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (134 KB) |  | HTML iconHTML  

    A typical MIMO system utilizes multiple antennas to transmit simultaneously several independent data streams to the receiver end. As a result of this inter-stream interference is said to occur since the reception of each stream at the receiver will be disturbed not only by noise but from the interference of other streams as well. In order to successfully detect and decode the received signal, joint detection and decoding can be employed to separate and recover the transmitted data in the best possible manner. This approach has huge complexity which grows exponentially as the number of antennas increases, thus prohibiting its implementation in a real time system. For real time implementation computationally effective methods are sought after but which often does not necessarily yield the best performance thus incurring a performance-complexity trade-off. The current research in this area has led to the development of both linear and non-linear techniques most of which are computationally intensive and complex. This paper discusses low complexity methods which are suitable for real time applications. View full abstract»

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  • Single edge based belief propagation algorithms for MIMO detection

    Publication Year: 2011 , Page(s): 1 - 5
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (162 KB) |  | HTML iconHTML  

    In this paper, two low-complexity belief propagation (BP) based detectors are proposed for multiple-input multiple-out (MIMO) system. The factor graph is leveraged to represent the MIMO channels, and based on which our algorithms are developed. Unlike the existing complicated standard BP detectors that consider all the edges when updating the messages, our algorithms only focus on single edge, which largely reduce computational complexity. In particular, we propose a novel Gaussian approximation with feedback information (GF) mechanism to enable the proposed single edge BP detector. In order to further improve the detection performance, we also propose to integrate the linear MIMO detector into the initial GF based single edge BP detector, where the pseudo priori (PP) information obtained from linear detector is judiciously exploited. Convergence and complexity analyses, along with the numerical simulations, verify that the proposed single edge BP detectors outperform the existing BP detectors in performance while with low complexity. View full abstract»

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  • Dynamic system performance of SISO, MISO and MIMO Alamouti schemes

    Publication Year: 2011 , Page(s): 1 - 5
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (199 KB) |  | HTML iconHTML  

    In this paper, the performance of a SISO system, a 2 × 1 MISO Alamouti transmission system and a 2 × N MIMO Alamouti transmission with maximum ratio combining (MRC) receiver system is studied in terms of mean flow throughput per user. A dynamic study (dynamic number of active users) is derived considering the downlink Rayleigh channel in a multi-cellular system. Two assumptions are considered: admission control based on a maximum number of users or no admission control. The studied cell is divided into concentric rings. Analytical expressions of the mean flow throughput of a user in each ring are proposed. A comparison between the performance of the different systems is presented and discussed. View full abstract»

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