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Broadband Multimedia Systems and Broadcasting (BMSB), 2011 IEEE International Symposium on

Date 8-10 June 2011

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Displaying Results 1 - 25 of 104
  • Femtocell technology combined to a condominium cabled infrastructure

    Publication Year: 2011 , Page(s): 1 - 5
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (402 KB) |  | HTML iconHTML  

    Fixed-mobile convergence has the potentiality to break down some of the physical barriers that now prevent telecom service providers from reaching all of their potential customers with all types of services. The breakthrough combination of wireline backhaul with wireless technology seems to represent a concrete quantum leap in terms of spectrum utilization, capacity and quality of service as well as it allows costs reduction and service differentiation. In the present paper an innovative approach to access the end user, relying on infrastructural integration of femtocellular technology with existing cabled networks, like MATV/SMATV plants, is proposed. The possible future deployment of new mobile networks, like LTE, in the digital dividend spectrum and in the GSM frequency band resulting from the re-farming process, makes this original broadband wireless access (BWA) approach an interesting solution to improve indoor radio coverage making possible, at the same time, a reduction of costs for both operators and users. View full abstract»

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  • SFN gain in broadcast networks

    Publication Year: 2011 , Page(s): 1 - 6
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (447 KB) |  | HTML iconHTML  

    For broadcast networks, the Single-Frequency Net work (SFN) mode is an alternative to the well-known Multi Frequency Network (MFN) mode, where instead of transmitters operating at different frequencies, all base stations use the same frequency. Besides an expected improvement of the quality of service due to the more homogeneous distribution of received signal strength, some areas will also show a degraded quality caused by the SFN echoes. In this paper, the SFN gain is defined as a parameter describing potential gain or interference. An unambiguous methodology to obtain the actual SFN gain is presented and the variation of the gain is investigated for a DVB-H network as a function of the signal strength difference received from different transmitters. This SFN gain can be used for coverage planning of future broadcast networks. View full abstract»

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  • Efficient adaptive bit-rate control for Scalable Video Coding by using Computational Complexity-Rate-Distortion analysis

    Publication Year: 2011 , Page(s): 1 - 6
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (300 KB) |  | HTML iconHTML  

    We present an adaptive pre-processing (pre-filtering) method and system for the efficient Scalable Video Coding (SVC). Our adaptive SVC prefiltering system enables to decrease motion activity, and in turn, enables to decrease quantization fluctuations within the background region of each layer of a SVC video sequence, which contains two or more layers. In turn, this enables to use smaller quantization parameters, but still to obtain the same compression rate for the optimal usage of encoder and decoder computational resources in order to achieve optimal video presentation quality. Our adaptive prefiltering system is very efficient since it is based on a SVC Computational Complexity-Rate-Distortion (C R-D) analysis, adding a complexity dimension to the conventional rate-distortion (R-D) analysis for the SVC coding. As a result, the SVC visual presentation quality at the decoder side is significantly improved even for the decoders with very limited computational resources, which can be very useful for various mobile devices, such as cellular phones. Also, we perform Region-of-Interest (ROI) SVC pre-processing for enabling providing efficient coding of the desired Region-of-Interest. The performance of the presented systems is demonstrated and compared with the Joint Scalable Video Model 9.19 (JSVM 9.19) reference software. View full abstract»

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  • Low complexity implementation of channel estimation and equalization for TDS-OFDM system

    Publication Year: 2011 , Page(s): 1 - 4
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (158 KB) |  | HTML iconHTML  

    To realize both the single and the dual transmit antenna modes in TDS-OFDM systems based on flexible frequency binary padding, a novel channel estimation and equalization algorithm has been proposed in this paper. A low complexity implementation architecture for this algorithm is also designed. The pipeline structure is used here to meet the real-time processing requirement and to increase the resource efficiency. The resource analysis shows that the proposed scheme significant reduces the implementation complexity while the simulation results from the FPGA test shows it has good bit error ratio (BER) performance. View full abstract»

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  • Equalization digital on-channel repeater with a feedback interference canceller for the ATSC terrestrial DTV system

    Publication Year: 2011 , Page(s): 1 - 4
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (375 KB) |  | HTML iconHTML  

    This paper proposes a novel equalization digital on-channel repeater (EDOCR) with a feedback interference canceller (FIC) for a single frequency network (SFN) of the advanced television systems committee (ATSC) terrestrial digital television (DTV) system. The proposed EDOCR with an FIC not only has high output power by the cancellation of feedback signals caused by insufficient antenna isolation through the FIC, but also shows better quality of output signals than conventional digital on-channel repeaters (DOCRs) by removing multipath signals existing between the main transmitter and DOCR, as well as residual feedback signals through an equalizer. Computer simulation results are provided to demonstrate the superior performance of the proposed EDOCR with an FIC. View full abstract»

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  • Heuristic optimization of DVB-T/H SFN coverage using PSO and SA algorithms

    Publication Year: 2011 , Page(s): 1 - 5
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (856 KB) |  | HTML iconHTML  

    This paper studies two of the available heuristic algorithms to optimize the digital broadcasting network's planning. Particle Swarm Optimization (PSO) and Simulated Annealing (SA) are compared working in different OFDM modes. These algorithms manipulate the information of the network with static delays in order to maximize the covered area as well as possible at minimum cost. Particle Swarm Optimization (PSO) and Simulated Annealing (SA) are compared working in a different OFDM modes and synchronization strategies. Furthermore, they have been used to estimate the coverage and the interference degree of the network planning placed in the Basque Country, in northern Spain. View full abstract»

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  • A selective transport framework for delivery MVC video over MPEG-2 TS

    Publication Year: 2011 , Page(s): 1 - 6
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (152 KB) |  | HTML iconHTML  

    Multiview video has gained significant interest in recent years. Generally speaking, Multiview video has more than one views from slightly different angles of the same scene. The huge amount of video data and the heterogeneous network condition pose great challenge for the transport of multiview video through internet or broadcast networks. In order to support variety of 3D application scenarios, selective transport of multi view video has to be deployed. This paper proposes a priority based selective transport framework of multiview video over MPEG-2 Transport Stream. The proposed framework achieves selective transport by extracting the related view components from MVC video as well as discarding lowest priority view components without obstructing the decoding process at the receiver client when the transport bandwidth is insufficient. To the best of our knowledge, this paper is the first to investigate a priority-based selective transport framework for delivery MVC video over MPEG-2 transport stream. View full abstract»

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  • Field measurements for ISDB-TB in the VHF band

    Publication Year: 2011 , Page(s): 1 - 6
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1975 KB) |  | HTML iconHTML  

    This paper presents field tests and analysis of the results of the fixed and mobile reception of Integrated Services Digital Broadcasting-Terrestrial version B (ISDB-TB) in the VHF band. A comparative analysis of DTV reception behavior in the VHF and UHF bands is presented. View full abstract»

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  • Low decoding complexity STBC design for turbo coded broadcast transmission

    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  

    In this paper, we study the Space Time Block Code (STBC) called Matrix D (MD) that enjoys low-complexity detection for broadcast transmission. Such a transmission uses a powerful channel code like a turbo code. To produce Log-Likelihood Ratio (LLR) for the channel decoder, we propose a soft Maximum Likelihood (ML) detector for MD STBC while keeping the same low-complexity order as the original one. Then, we optimize the MD STBC for low Signal to Noise Ratio (SNR) under the trace criterion. The performance of the concatenation of a turbo code with optimized MD is given. A gain of almost 0.2 dB is obtained between optimized MD and original MD. However, the proposed code loses its full-diversity as its determinant is equal to 0. Then, a tradeoff angle is chosen and a low-complexity detection full-rate full-diversity STBC is designed for turbo coded broadcast transmission which performs well for both low and high SNR. View full abstract»

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  • Photogrammetric satellite service prediction - Correlation of RF measurements and image data

    Publication Year: 2011 , Page(s): 1 - 6
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (3891 KB) |  | HTML iconHTML  

    This paper addresses the image-based characterization of the land mobile satellite channel. In a measurement campaign, the signal power levels of the Satellite Digital Audio Radio Services (SDARS) in the U.S. were recorded. In parallel, a flsheye camera on the roof of the measurement van continuously acquired images of the upper hemisphere. Using time, location and heading information from GPS, the satellite positions are determined in the hemispheric images. Analyzing the regions around the satellites by image processing methods, the degree of visibility of the satellites is extracted which acts as an indicator for the current shadowing conditions. Using this optical method, shadowing parameters for the land mobile satellite channel of arbitrary satellite constellations can be derived. This method can be helpful for cost-efficient, large-scale network planning. View full abstract»

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  • QoS prediction for mobile satellite broadcasting with angle diversity based on measurements

    Publication Year: 2011 , Page(s): 1 - 8
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (750 KB) |  | HTML iconHTML  

    To meet the high quality of service requirements for mobile satellite applications, diversity combining techniques are used to mitigate fading effects in the satellite propagation channel. In this paper the performance of multi-satellite diversity (or angle diversity) in combination with time diversity is presented. The achievable diversity gain depends on the environmental conditions, the satellite elevation and the angular separation of the satellites. To assess the performance of multi-satellite systems, high-power broadcasting signals in the S-band from HEO and GEO satellites of the Sirius XM Radio system were recorded simultaneously along the east coast of the USA. Based on the measured signal power levels, the ESR(5) fulfillment criteria are predicted for various configurations incorporating different margins, time interleaver lengths, and satellite constellations. The results are presented for six different environments: urban, suburban, commercial, forest, intermediate tree shadowed, and highway. View full abstract»

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  • A study of network performance with application to Adaptive HTTP Streaming

    Publication Year: 2011 , Page(s): 1 - 6
    Cited by:  Papers (9)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (894 KB) |  | HTML iconHTML  

    We present a study of the performance of Adaptive HTTP Streaming over different access networks. Adaptive HTTP Streaming is on the verge of becoming the de-facto standard for multimedia streaming over the Internet and standards exist for its implementation. However, important aspects like media bitrate, segment duration and buffer requirements are not specified. We simulated characteristical HTTP streaming sessions over typical networks like DSL, WLAN and UMTS in order to classify the impact of these aspects on the overall performance of a streaming system. The measurements have shown a frequency of late segments between 7.88% for cellular networks and 17.72% for wireless LAN connections with more than 50% of the segments still arriving in less than 50% of the respective segment duration. The influence of different segment durations was not significant. The results prove the high variability of these access technologies and thus the immediate need for adaptivity in an HTTP streaming system. View full abstract»

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  • Multi-rate LDPC codes for DTV transmission by known-bits padding

    Publication Year: 2011 , Page(s): 1 - 6
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1314 KB) |  | HTML iconHTML  

    Modern DTV broadcasting systems, such as DVB and the Chinese DTMB system, usually have multiple code rates for forward error correction to accommodate a variety of channel conditions. In these systems, each code rate corresponds to a special set of code words, which put a limit on rate granularity and thus cannot achieve seamless code rate adaptation. To solve this problem, we propose a known-bits padding scheme to generate multi-code-rate LDPC codes of arbitrary granularity. In our scheme, we take a standardized LDPC code of specific rate as mother code, then pad known-bits according to the targeted code rate and given shortening optimization algorithm. Simulation study shows that our proposed scheme can obtain satisfying performance in terms of code rate flexibility and decoding threshold. View full abstract»

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  • A new transport scheme for hybrid delivery of content over broadcast and broadband

    Publication Year: 2011 , Page(s): 1 - 6
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (428 KB) |  | HTML iconHTML  

    This paper presents a new media transport scheme that flexibly combines media components on broadcast channels and broadband networks so that end users can conveniently consume favorite content without being aware of its delivery channels. By taking advantage of the different delivery characteristics of broadcast channels and broadband networks, hybrid delivery offers an effective means of stably providing customized content to each user. In hybrid delivery systems, generic components for a wide range of users are delivered on broadcast channels, and additional components customized to users' interests or locations are delivered on broadband networks. Our proposed scheme enables each user to flexibly combine those components. We have implemented the proposed scheme in a prototype hybrid delivery system. The experimental results demonstrate that the scheme achieves hybrid delivery of content on broadcast channels and broadband networks. View full abstract»

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  • Real-time subtitle synchronization in live television programs

    Publication Year: 2011 , Page(s): 1 - 6
    Cited by:  Patents (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (314 KB) |  | HTML iconHTML  

    The number of live programs in broadcast and IPTV Digital Television is increasing as the offer of pre-recorded multimedia in Internet television and video on-demand grows. For many people, subtitles are the only way to access the audio of television programs and in live subtitling environments the audio transcription process will deliver the corresponding subtitles several seconds after the speech fragment has been received. The disturbing effect of the resulting lack of synchronism is still a challenging issue in the accessibility to live-multimedia. This paper presents the application of an Automatic Speech Recognition and synchronizing system, tailored for three different live television environments (i.e. news programs, sports, magazine). Individual subtitle delays are measured and used to synchronize video/audio and subtitles before delivering the TV program in a dedicated IPTV channel. View full abstract»

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  • Radio channel models laboratory comparative study for the L-band DAB/DMB system

    Publication Year: 2011 , Page(s): 1 - 8
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (487 KB) |  | HTML iconHTML  

    This paper presents the performance results of multipath fading characterizations performed in the laboratory with a single and dual-antenna DAB/DMB software receiver, using a sophisticated hardware channel simulator (Propsim FE). Different radio channel models corresponding to various scenarios and environments (urban, suburban, indoor, outdoor, SFN) have been tested and compared. For a single antenna scenario, it is shown that for the same environments, the COST207 and 3GPP channel models offer almost a similar performance. Moreover, it is found that in the case of indoor channel reception (WLAN profiles) and for a carrier to noise ratio (C/N) of 15-20 dB, the receiver maintains an acceptable level of pcBER for proper audio decoding. This observation also applies to the recently proposed DVB-H multipath channel profiles, except for the motorway rural channel (MR) at 100 km/h where the receiver fails to operate correctly at this mobile speed. In dual-antenna scenarios, the maximal ratio combining (MRC) diversity technique provides a clear improvement to the performance of the dual-antenna based DAB/DMB receiver for all multipath channel profiles tested. Finally, it is shown that DAB/DMB transmission with a simple delay diversity scheme can be effective to mitigate multipath flat fading degradation. View full abstract»

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  • Enhanced prioritization for video streaming over wireless home networks with IEEE 802.11e

    Publication Year: 2011 , Page(s): 1 - 6
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (296 KB) |  | HTML iconHTML  

    Cyclic intra refresh is able to mitigate temporal error propagation. This paper exploits the unequal error sensitivity introduced within individual video frames when using a cyclic intra refresh line of macroblocks. Slice-level priority is proposed based on the relative position of a slice with respect to the intra refresh line. Two in-frame prioritization schemes are investigated: a region-based priority assignment and a packet-based priority assignment. The region-based scheme assigns packet priorities in the order of bitstream arrival to the packetizer, whereas the packet-based scheme assigns priorities within regions and does not follow bitstream arrival order to the packetizer. The proposed schemes do not add any bitrate or computational overheads and no decoder modification is required. Simulation results for streaming high-definition video over a quality-of-service enabled home wireless network show that the packet-based scheme can achieve quality gains up to 3 dB over sending video without applying priorities. View full abstract»

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  • Reduced reference image quality assessment using Principal Component Analysis

    Publication Year: 2011 , Page(s): 1 - 6
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (574 KB) |  | HTML iconHTML  

    With the tendency of converging services delivered on wired and wireless networks, the consumer expectancy includes live video streaming. In this context, the objective image and video quality assessment becomes an essential but a challenging requirement. With the rapid evolution of the wireless video applications, the continuation of the Quality of Service (QoS) is a key paradigm for the roll-out of these services, which demands for an efficient quality evaluator for the dynamic monitoring and parameter setting of the digital video system. In this paper, we propose a Reduced-Reference (RR) image quality assessment metric based on the Principal Component Analysis (PCA). In our metric, the transformed data set is obtained which represents the original data solely in terms of the eigenvectors we choose, giving us the most efficient expression of the data. The mean gradient values are calculated from the transformed data using edge detection methods based on the Sobel-operator. We define a Quality Index that measures the difference between our metric's values computed on the transmitted and received images, respectively. The experimental results show that our RR-PCA proposed metric correlates well with the subjective quality scores. View full abstract»

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  • A computationally efficient simulation chain for OFDM-based wireless systems

    Publication Year: 2011 , Page(s): 1 - 6
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (447 KB) |  | HTML iconHTML  

    We present a method for modeling OFDM transmission over time- and frequency-selective fading channels using finite-state hidden Markov models. The proposed approach has improved fading autocorrelation accuracy compared to previous related models. Also, we present a way of producing log likelihood ratio values as output of the finite-state model for any signal constellation. As a case study, we configure the proposed model according to the second generation terrestrial digital video broadcast system operating over a typical urban mobile channel. View full abstract»

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  • Performance evaluation of DQOAS algorithm in case of applications generating VoIP and video streaming when a new QoS prioritization scheme for LTE is used

    Publication Year: 2011 , Page(s): 1 - 6
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (497 KB) |  | HTML iconHTML  

    In a wireless environment, the radio resources fairly shared among the connected devices are used to deliver the required content. Next Generation Networks like WiMAX and LTE are using advanced mechanisms to differentiate users and data streams in order to increase the number of simultaneously connected users while maintaining high spectrum utilization. In the particular case of applications generating a traffic mix, using the general LTE mechanisms for stream differentiation and data prioritization can reduce the total number of satisfied users because the user quality of experience is not considered as a key parameter in the resource scheduling algorithm. Dynamic Quality Oriented Adaptation Scheme (DQOAS) considers QoE to be one of the important factors in the delivery process and manages to increase the number of per-application satisfied users. This paper evaluates the performances of DQOAS algorithm in conjunction with a new QoS parameters mapping scheme in case of applications generating VoIP, video streaming and web browsing traffic. The performances are assessed in terms of total number of satisfied users, link efficiency and BLER and are compared with the original QoS mechanism when different schedulers are used. The results are showing that DQOAS algorithm performs very well in case of an application is also generating VoIP traffic, increasing the number of satisfied users. View full abstract»

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  • Inter-intra frame segmentation using colour and motion for region of interest coding of video

    Publication Year: 2011 , Page(s): 1 - 4
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (655 KB) |  | HTML iconHTML  

    In this paper, we present a segmentation method that is based on combined colour with temporal features like motion vectors. In the past segmentation methods for region of interest (ROI) coding has only based segmentation on one feature such as motion, colour and luminance etc. The segmentation system that we proposed is based on two features there by combining the strengths of each separate segmentation technique e.g. fidelity and consistency of region combined with moving regions. First of all we segment image (pixels level) inside frame based on colour and then in the second step we segments the images (block level) in a set of frames based on motion. This is initial work of our project where we want to compress video by removing perceptual redundancy based on human visual perceptual capabilities. Human perceive images in term of objects which can never be captured as a whole image or its global features. In order to identify the Region of Interest (ROI) from the frames (and sequence of frames), this efficient segmentation is very important. As a first step, for colour based image segmentation we use an efficient method where speed is our primary concern because we have to process multi frames per second and for motion based image segmentation we use block based motion estimation combined with a motion threshold. Quality of the motion segmentation will be considered in the second step where we use morphological operators to remove interior and exterior noise. Since segmentation is based on blocks, where we have quite less number of pixels than in the image, so speed in not such a big issue. For the third step we explore how to combine the motion and colour segmented images. Our first algorithm is based on combining the edges of the colour segmented image with the edges of the block based motion estimated image. We are working on other algorithms to try and obtain more concise and consistent results. This paper describes our first approach. View full abstract»

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  • Optimizing point-to-multipoint transmissions in High Speed Packet Access networks

    Publication Year: 2011 , Page(s): 1 - 5
    Cited by:  Papers (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (167 KB) |  | HTML iconHTML  

    In this paper an innovative Radio Resource Management (RRM) algorithm is proposed with the purpose of increasing High Speed Packet Access (HSPA) performances, in terms of system capacity and service quality, when the Multimedia Broadcast Multicast Services (MBMS) is supplied. The proposed RRM algorithm exploits channel quality indications to set up point-to-multipoint connections to subgroups of multicast users and to select the proper modulation and coding schemes on the downlink. The number of subgroups is determined through an optimization technique that also takes into account the user satisfaction. An exhaustive simulation campaign is conducted to compare the proposed algorithm with the most promising approaches in the literature. Comparisons aim to assess the capability of the proposed RRM algorithm to efficiently manage group oriented services by providing an increment in terms of user satisfaction. View full abstract»

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  • Indoor direction finding of terrestrial TV signals based on total recording

    Publication Year: 2011 , Page(s): 1 - 6
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1097 KB) |  | HTML iconHTML  

    We have shown that high-accuracy DOA estimation can be obtained by the use of a total recording technique which simultaneously records the output signals from the elements of a virtual array antenna and a reference antenna, representing the target signals and a high-quality reference signal, and performing a correlation analysis of these signals. The method proposed in this paper enables two-branch recording of the target signals and the reference signal. By adopting two-dimensional virtual array measurement, we obtained an angular spectrum in full range of 0°-360°. Outdoor measurements were first performed to investigate the validity of the proposed measurement method. The results confirmed its effectiveness in determining DOAs very accurately. We then investigated the system performance in an indoor environment, which is the ultimate objective of this study. The angular spectrum obtained showed five arriving waves, and allowed determination of the angular profile and the wave propagation structure. In conclusion, we have had a very accurate measurement tool for indoor propagation. View full abstract»

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  • Design of a new Queue management mechanism to optimize the use of shared resources in real-time interactive multimedia services

    Publication Year: 2011 , Page(s): 1 - 6
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (629 KB) |  | HTML iconHTML  

    Present paper describes the design of a new Queue Management Mechanism that allows the optimization in the use of shared network resources by different flows with high QoS constraints. The new real-time multimedia interactive services require network devices whose behavior complies with high time constraints. Hence, the proposed queue management mechanism is focused on providing a reduced delay and a controlled variation of the delay. This work describes a new conceptual model of queue management mechanism based on the innovative fundamentals of Network Coding. The proposed solution provides a considerable delay and delay variation (jitter) improvement. The concept has been implemented in a discrete event simulator, so that we can compare the behavior of the new mechanism based on Network Coding faced with classical queue management techniques based on store-and-forward. Afterwards, we describe the methodology used in order to obtain the formulation that characterizes the QoS response of the system. Based on a detailed design of experiments, the influence of the different factors that condition the system response is studied, so that the proposed improvements can be analyzed and potential future research fields can be glimpsed. View full abstract»

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  • A simplified MMSE detection for iterative receivers in multiple antenna systems

    Publication Year: 2011 , Page(s): 1 - 5
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (273 KB) |  | HTML iconHTML  

    Simplified minimum mean square error (MMSE) detection technique combined with soft interference cancellation (SoIC) is proposed for the iterative receivers in multiple antenna systems. To avoid repeated matrix inversions required to obtain the MMSE filter coefficients during the iteration between the soft detector and decoder, simplified matrix inversion techniques are applied to calculate the filter coefficient matrix. Simulation results show that the proposed MMSE detections with SoIC indicate a comparable or slightly degraded detection performance while achieving a significantly reduced complexity as compared to the conventional MMSE detection with SoIC. View full abstract»

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