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Wireless Communications, IEEE Transactions on

Issue 8 • Date August 2010

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Displaying Results 1 - 25 of 35
  • Table of contents

    Publication Year: 2010 , Page(s): c1
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  • [Staff list]

    Publication Year: 2010 , Page(s): c2
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  • Near-Optimal Joint Antenna Selection for Amplify-and-Forward Relay Networks

    Publication Year: 2010 , Page(s): 2401 - 2407
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (295 KB) |  | HTML iconHTML  

    This paper considers a joint antenna selection method in amplify-and-forward (AF) relay networks where the source, relay and destination terminals are all equipped with multiple antennas. The fact that the system's full diversity can be maintained by antenna selection at each terminal makes it a promising solution to reduce the hardware complexity of multiple-input multiple-output (MIMO) terminals while realizing the diversity benefits of MIMO in relay networks. Since the exhaustive search for antenna subset selection is computationally prohibitive, we devise a low-complexity near-optimal joint antenna selection algorithm based on a constrained cross entropy optimization (CCEO) method to maximize the achievable rate and the convergence is guaranteed. Simulation results reveal both the effectiveness and the efficiency of the proposed algorithm and the significant performance improvement over other benchmark selection techniques. Finally, it is illustrated that the proposed CCEO algorithm can always achieve near-optimal results regardless of the number of selected antennas, outage probabilities and the signal-to-noise ratios (SNRs) at the terminals. View full abstract»

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  • Integration Interval Determination Algorithms for BER Minimization in UWB Transmitted Reference Pulse Cluster Systems

    Publication Year: 2010 , Page(s): 2408 - 2414
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (550 KB) |  | HTML iconHTML  

    A recently proposed transmitted reference pulse cluster (TRPC) structure contains compactly spaced reference and data pulses, and enables a low complexity, robust and practical auto-correlation detector to be used at the receiver. Previous research indicated that the integration interval of the auto-correlation detector is critical to the performance of TRPC. Therefore, in this paper, three practical data-aided algorithms are introduced to determine the integration interval of the TRPC structure: the conventional threshold-crossing concept, the new bit error rate (BER) minimization based approach, and the new hybrid scheme that combines threshold-crossing and the BER minimization concepts. The performances of the three schemes are extensively evaluated by simulation. Results show that, the BER minimization based approach and the hybrid scheme demonstrate around 2 dB performance gain over the threshold-crossing scheme in IEEE 802.15.4a channels. Moreover, the hybrid scheme yields close performance to the BER minimization based scheme with much reduced complexity. View full abstract»

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  • Analysis of a Simple Recruiting Method for Cooperative Routes and Strip Networks

    Publication Year: 2010 , Page(s): 2415 - 2419
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (561 KB) |  | HTML iconHTML  

    The opportunistic large array (OLA) is the basis for a simple cooperative transmission protocol that is suitable for broadcasting in wireless sensor networks and in which every node transmits once per broadcast. OLA with transmission threshold (OLA-T) is an energy-efficient extension of the OLA protocol that limits node participation during broadcasting. Performance of OLA-T has been studied for disc-shaped networks. In this paper, we propose a method to systematically set the transmission threshold and design the OLAs for two-dimensional strip-shaped networks. Theoretical bounds and conditions for achieving sustained OLA propagation and reducing the total energy consumption in the network using OLA-T have been derived in this paper. These results would also apply to arbitrarily shaped networks that have node participation limited to strip-shaped collections. View full abstract»

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  • Joint Channel and Network Coding for Cooperative Diversity in a Shared-Relay Environment

    Publication Year: 2010 , Page(s): 2420 - 2423
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (248 KB) |  | HTML iconHTML  

    In this paper we propose a cooperative diversity scheme for the communication model of two sources sharing a single relay. The scheme uses algebraic code superposition relaying in the multiple access fading channel to create spatial diversity under the constraint of limited communications resources. We also describe in detail a novel computationally efficient message passing algorithm at the destination's decoder which extracts the substantial spatial diversity contained in the code superposition and signal superposition. The decoder is based on a sliding window structure where certain a posteriori LLRs are retained to form a priori LLRs for the next decoding. We show that despite the simplicity of the proposed scheme, diversity gains are efficiently leveraged by the simple combination of channel coding at the sources and network coding at the relay. View full abstract»

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  • Transmit Beamforming with Power Adaptation in Downlink Multi-User Systems

    Publication Year: 2010 , Page(s): 2424 - 2429
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (249 KB) |  | HTML iconHTML  

    This paper addresses power adaptation in the context of beamforming in the downlink of a cellular system. Specifically, we consider a system consisting of a base station (BS) with multiple antennas and multiple users each with a single antenna, in which the BS selects the user with the best channel for transmission. Compared to the scheme minimizing the bit error rate (BER) using a fixed instantaneous power, the BER performance can be further improved by adapting the instantaneous power according to the channel of the selected user. The optimal power adaptation (OPA) policy is derived, and its BER is compared with the case of a sub-optimal policy called channel inversion (CI). With a novel analytical approach, the BER performances of OPA and CI are quantified and CI is shown to be near-optimal for a multi-user multi-antenna system at moderate to large SNR, unlike the single-user single-antenna case. Finite peak power constraint is also considered for both OPA and CI. View full abstract»

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  • A Low-Complexity Scheme for Frequency Estimation in Uplink OFDMA Systems

    Publication Year: 2010 , Page(s): 2430 - 2437
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (390 KB) |  | HTML iconHTML  

    Frequency estimation in the uplink of an orthogonal frequency-division multiple-access system is a challenging task due to the presence of multiple carrier frequency offsets. Many existing solutions are too complex for practical implementation, while others are restricted to a specific subcarrier assignment strategy. Motivated by the above consideration, in this letter we propose a novel frequency estimator that allows flexible subcarrier assignment while requiring a low computational burden. Our scheme exploits the repetitive structure of the users' training sequences, which are properly designed so as to minimize the multiple-access interference arising in the presence of frequency errors. Computer simulations are used to assess the effectiveness of the proposed method and to make comparisons with competing alternatives. View full abstract»

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  • A Novel Multistage Group Detection Technique and Applications

    Publication Year: 2010 , Page(s): 2438 - 2443
    Cited by:  Papers (3)  |  Patents (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (284 KB) |  | HTML iconHTML  

    In this letter, a multistage group detection (MSGD) approach to nonlinear equalization is proposed. At each stage, symbols are divided into groups, and maximum-likelihood detection (MLD) within the group is performed. The MLD process identifies a number of promising group values. It is constrained to only consider candidate symbol values identified in the previous stage. Groups are formed by combining groups from the previous stage. For example, symbols are detected one at a time, then two at a time, then four at a time, and so on. The last stage is a form of constrained maximum-likelihood sequence detection (MLSD). The overall demodulation process can be viewed as approximate MLSD, and results show that near-MLSD performance is possible with reasonable complexity. While the High Speed Downlink Packet Access (HSDPA) cellular system is used as an example, the approach can be applied other situations, including the Long Term Evolution (LTE) uplink and MIMO. View full abstract»

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  • Distributed Multicell-MISO Precoding Using the Layered Virtual SINR Framework

    Publication Year: 2010 , Page(s): 2444 - 2448
    Cited by:  Papers (30)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (228 KB) |  | HTML iconHTML  

    In this letter, we address the problem of distributed multi-antenna cooperative transmission in a cellular system. Most research in this area has so far assumed that base stations not only have the data dedicated to all the users but also share the full channel state information (CSI). In what follows, we assume that each base station (BS) only has local CSI knowledge. We propose a suboptimal, yet efficient, way in which the multicell MISO precoders may be designed at each BS in a distributed manner, as a superposition of so-called virtual SINR maximizations: a virtual SINR maximizing transmission scheme yields Pareto optimal rates for the MISO Interference Channel (IC); its extension to the multicell MISO channel is shown to provide a distributed precoding scheme achieving a certain fairness optimality for the two link case. We illustrate the performance of our algorithm through Monte Carlo simulations. View full abstract»

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  • MIMO Broadcast Channels with Spatial Heterogeneity

    Publication Year: 2010 , Page(s): 2449 - 2454
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (328 KB) |  | HTML iconHTML  

    We develop a realistic model for multiple-input multiple-output (MIMO) broadcast channels, where each randomly located user's average SNR depends on its distance from the transmitter. With perfect channel state information at the transmitter (CSIT), the average sum capacity is proven to scale for many users like αM/2 log K instead of M log log K, where α, M, and K denote the path loss exponent, the number of transmit antennas, and the number of users in a cell. With only partial CSIT, the sum capacity at high SNR eventually saturates due to interference, and the saturation value scales for large B like MB/M-1, where B denotes the quantization resolution for channel feedback. View full abstract»

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  • A Reduced-Complexity PTS-Based PAPR Reduction Scheme for OFDM Systems

    Publication Year: 2010 , Page(s): 2455 - 2460
    Cited by:  Papers (10)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (267 KB) |  | HTML iconHTML  

    In this paper, a reduced-complexity partial transmit sequences (PTS) scheme is proposed to resolve the intrinsic high peak-to-average power ratio (PAPR) problem of orthogonal frequency division multiplexing (OFDM) systems. In the proposed PTS scheme, a cost function Qn is generated by summing the power of the time-domain samples at time n in each subblock. Only those samples with Qn greater than or equal to a preset threshold are used for peak power calculation during the process of selecting a candidate signal with the lowest PAPR for transmission. As compared to the conventional PTS scheme, the proposed one achieves almost the same PAPR reduction performance with much lower computational complexity. View full abstract»

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  • Performance of Optimum Combining in a Poisson Field of Interferers and Rayleigh Fading Channels

    Publication Year: 2010 , Page(s): 2461 - 2467
    Cited by:  Papers (19)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (367 KB) |  | HTML iconHTML  

    This paper studies the performance of antenna array processing in distributed multiple access networks without power control. The positions of nodes are determined by a Poisson point process. Desired and interfering signals are subject to both path-loss (with an exponent greater than 2) and to independent Rayleigh fading. Using these assumptions, we derive the exact closed form expression for the cumulative distribution function of the output signal-to-interference-plus-noise ratio when optimum combining is applied. This results in a pertinent measure of the network performance in terms of the outage probability, which in turn provides insights into the network capacity gain that could be achieved with antenna array processing. We present and discuss examples of applications, as well as some numerical results. View full abstract»

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  • An Optimized Iterative (Turbo) Receiver for OFDM Systems with Type-I Hybrid ARQ: Clipping and CFO Cases

    Publication Year: 2010 , Page(s): 2468 - 2477
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (575 KB) |  | HTML iconHTML  

    An optimized iterative (Turbo) receiver for Orthogonal Frequency Division Multiplexing (OFDM) transmission is proposed for improved performance when used with type-I hybrid Automatic Repeat Request (ARQ) protocols. The proposed receiver is a Maximum Aposteriori Expectation-Maximization (MAP-EM) Turbo processor that exploits information from all available transmissions of a packet, including failed and new ones. Two distinct practical problems associated with OFDM are considered: (i) Clipping due to non-linearities in the transmit amplifier, and (ii) Carrier frequency offset (CFO). In the optimized scheme, failed transmissions are combined with the new ones to form an iterative receiver that jointly estimates the channel, compensates for the distortion (clipping, or CFO) and decodes the message. The modulation employed is M-ary Phase Shift Keying (MPSK). The system uses an embedded pilot structure for initial channel estimation of the channel, which is assumed doubly-selective. It is shown that gains on the order of 3 dB are achieved in the packet rejection probability with the proposed system. The performance of the optimized system is close to that of the ideal system, i.e. one that performs packet combining with perfect channel knowledge, no clipping, and no CFO. View full abstract»

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  • End-to-End Average BER in Multihop Wireless Networks over Fading Channels

    Publication Year: 2010 , Page(s): 2478 - 2487
    Cited by:  Papers (18)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (653 KB) |  | HTML iconHTML  

    This paper addresses the problem of finding an analytical expression for the end-to-end Average Bit Error Rate (ABER) in multihop Decode-and-Forward(DAF) routes within the context of wireless networks. We provide an analytical recursive expression for the most generic case of any number of hops and any single-hop ABER for every hop in the route. Then, we solve the recursive relationship in two scenarios to obtain simple expressions for the end-to-end ABER, namely: (a) The simplest case, where all the relay channels have identical statistical behaviour; (b) The most general case, where every relay channel has a different statistical behaviour. Along with the theoretical proofs, we test our results against simulations. We then use the previous results to obtain closed analytical expressions for the end-to-end ABER considering DAF relays over Nakagami-m fading channels and with various modulation schemes. We compare these results with the corresponding expressions for Amplify-and-Forward (AAF) and, after corroborating the theoretical results with simulations, we conclude that DAF strategy is more advantageous than the AAF over Nakagami-m fading channels as both the number of relays and m-index increase. View full abstract»

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  • Malicious User Detection in a Cognitive Radio Cooperative Sensing System

    Publication Year: 2010 , Page(s): 2488 - 2497
    Cited by:  Papers (30)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (398 KB) |  | HTML iconHTML  

    Reliable detection of primary users (PUs) is an important task for cognitive radio (CR) systems. Cooperation among a few spectrum sensors has been shown to offer significant gain in the performance of the CR spectrum-sensing system by countering the shadow-fading effects. We consider a parallel fusion network in which the sensors send their sensing information to an access point which makes the final decision regarding presence or absence of the PU signal. It has been shown in the literature that the presence of malicious users sending false sensing data can severely degrade the performance of such a cooperative sensing system. In this paper, we investigate schemes to identify the malicious users based on outlier detection techniques for a cooperative sensing system employing energy detection at the sensors. We take into consideration constraints imposed by the CR scenario such as the lack of information about the primary signal propagation environment and the small size of the sensing data samples. Considering partial information of the PU activity, we propose a novel method to identify the malicious users. We further propose malicious user detection schemes that take into consideration the spatial information of the CR sensors. The performance of the proposed schemes are studied using simulations. View full abstract»

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  • Low Complexity Pre-Equalization Algorithms for Zero-Padded Block Transmission

    Publication Year: 2010 , Page(s): 2498 - 2504
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (419 KB) |  | HTML iconHTML  

    The zero-padded block transmission with linear time-domain pre-equalizer is studied in this paper. A matched filter is exploited to guarantee the stability of the zero-forcing (ZF) and minimum mean square error (MMSE) pre-equalization. Then, in order to compute the pre-equalizers efficiently, an asymptotic decomposition is developed for the positive-definite Hermitian banded Toeplitz matrix. Compared to the direct matrix inverse methods or the Levinson-Durbin algorithm, the computational complexity of the proposed algorithm is significantly decreased and there is no bit error rate degradation when data block length is large. View full abstract»

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  • The Relay Selection and Transmission Trade-off in Cooperative Communication Systems

    Publication Year: 2010 , Page(s): 2505 - 2515
    Cited by:  Papers (17)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (517 KB) |  | HTML iconHTML  

    A common and practical paradigm in cooperative communication systems is the use of a dynamically selected "best" relay to decode and forward information from a source to a destination. Such systems use two phases - a relay selection phase, in which the system uses transmission time and energy to select the best relay, and a data transmission phase, in which it uses the spatial diversity benefits of selection to transmit data. In this paper, we derive closed-form expressions for the overall throughput and energy consumption, and study the time and energy trade-off between the selection and data transmission phases. To this end, we analyze a baseline non-adaptive system and several adaptive systems that adapt the selection phase, relay transmission power, or transmission time. Our results show that while selection yields significant benefits, the selection phase's time and energy overhead can be significant. In fact, at the optimal point, the selection can be far from perfect, and depends on the number of relays and the mode of adaptation. The results also provide guidelines about the optimal system operating point for different modes of adaptation. The analysis also sheds new insights on the fast splitting-based algorithm considered in this paper for relay selection. View full abstract»

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  • Adaptive Modulation for MIMO Systems with Channel Prediction Errors

    Publication Year: 2010 , Page(s): 2516 - 2527
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (711 KB) |  | HTML iconHTML  

    The performance of multiple-input multiple-output (MIMO) systems using spatial multiplexing is analyzed under channel prediction errors. We derive exact closed-form expressions for the conditional and average bit error rate (BER) for both fixed and adaptive modulation. We apply our analysis to design a rate adaptation policy that optimally adapts antenna use between beamforming and spatial multiplexing. Our results indicate that the prediction error degrades BER in MIMO systems with spatial multiplexing much more than in MIMO systems with beamforming due to the self-interference that arises from channel coupling. In particular, if interference between eigenchannels is high, spatial multiplexing should not utilize the weakest eigenchannels. In our policy, beamforming is used when prediction error is high to avoid interference, whereas multiplexing is used when it is low to achieve the maximum multiplexing gain. We show that this policy improves performance over prior adaptive policies that have been proposed in the literature. View full abstract»

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  • Multiuser Cooperative Multiplexing with Interference Suppression in Wireless Relay Networks

    Publication Year: 2010 , Page(s): 2528 - 2538
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (613 KB) |  | HTML iconHTML  

    In this paper, we consider multiuser cooperative multiplexing schemes in cellular networks with fixed relays and address the problem of inter-user interference. We propose two schemes to mitigate the effect of the interference: an interference cancellation scheme and a cooperative precoding scheme. The interference cancellation scheme utilizes the broadcast nature of the signal transmitted to the fixed relay, and is based on a decode-and-forward relaying protocol. We provide a capacity bound for the proposed scheme, and also propose a power reduction scheme for the fixed relay. For the cooperative precoding scheme, we employ a cooperative linear filter at the transmitter to eliminate interference. Simulation results show that both proposed schemes enhance the achievable throughput significantly. View full abstract»

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  • Pilot-Aided Multicarrier Channel Estimation via MMSE Linear Phase-Shifted Polynomial Interpolation

    Publication Year: 2010 , Page(s): 2539 - 2549
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (382 KB) |  | HTML iconHTML  

    Current wireless multicarrier systems commonly adopt pilot-aided channel estimation, for which a simplest and least restrictive technique is polynomial interpolation in the frequency domain. For channels with large delay spreads, however, the performance of low-order polynomial interpolation suffers from modeling error. The problem may be remedied by adding a linear phase shift to the interpolator, or equivalently, a "window shift" in the time domain. We derive a method to estimate the optimal window shift, in the minimum mean-square error (MMSE) sense, for polynomial-interpolative channel estimation of arbitrary order. As a practical application, we show how to apply the resultant technique to Mobile WiMAX downlink channel estimation. In addition, we propose a method to automatically select the interpolation order based on some estimated MSE. View full abstract»

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  • Combination of MRC and Distributed Space-Time Coding in Networks with Multiple-Antenna Relays

    Publication Year: 2010 , Page(s): 2550 - 2559
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (414 KB) |  | HTML iconHTML  

    Distributed space-time coding (DSTC) is a cooperative scheme for wireless relay networks that achieves full diversity without channel information at the relays. In this paper, the use of maximum-ratio combining (MRC) at multiple-antenna relays in combination with DSTC is proposed. Simulation and theoretical analysis show that the new scheme outperforms the original DSTC. In some network scenarios, it can even improve the scaling of the error rate with the transmit power. Furthermore, the proposed scheme requires a shorter training interval than DSTC. View full abstract»

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  • How Much Coherent Interval Should be Dedicated to Non-Redundant Diagonal Precoding for Blind Channel Estimation in Single-Carrier Block Transmission?

    Publication Year: 2010 , Page(s): 2560 - 2574
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (557 KB) |  | HTML iconHTML  

    Transmit precoding is a key technique for facilitating blind channel estimation at the receiver but the impact due to precoding on the channel capacity is scarcely addressed in the literature. In this paper we consider the single-carrier block transmission with cyclic prefix, in which a recently proposed diagonal-precoding assisted blind channel estimation scheme via covariance matching is adopted to acquire the channel information. It is shown that, when perfect channel knowledge is available at the receiver, the optimal noise resistant precoder proposed in the literature incurs the worst-case capacity penalty. When the coherent interval is finite, channel mismatch occurs due to finite-sample covariance matrix estimation. Thus, we aim to determine how much of the coherent interval should be dedicated to precoding in order to trade channel estimation accuracy for the maximal capacity. Toward this end, we leverage the matrix perturbation theory to derive a closed-form capacity measure which explicitly takes account of the channel uncertainty in the considered blind estimation setup. Such a capacity metric is seen to be a complicated function of the precoding interval. To facilitate analysis, an approximate formula for the derived capacity measure is further given. This allows us to find a closed-form estimate of the capacity-maximizing precoding time fraction, and can also provide insights into the optimal tradeoff between channel estimation accuracy and achievable capacity. Numerical simulations are used for evidencing the proposed analytic study. View full abstract»

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  • Dynamic Spectrum Access Using a Network Coded Cognitive Control Channel

    Publication Year: 2010 , Page(s): 2575 - 2587
    Cited by:  Papers (10)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (751 KB) |  | HTML iconHTML  

    In this paper we propose a Dynamic Spectrum Access scheme which allows the users to opportunistically and efficiently access the channels available for communications. It addresses the following important aspects of opportunistic spectrum access: 1) implementation of the control channel, 2) multi-channel medium access control, 3) primary user detection, and 4) secondary reuse of spectrum unused by primary users. The main features of the scheme are that it is completely distributed, it does not need dedicated spectrum resources for control purposes, but rather leverages on a virtual control channel which is implemented using Network Coding techniques, and it exploits a cooperative detection strategy to identify unused spectrum. Due to these aspects, our proposal represents a significant improvement with respect to existing Dynamic Spectrum Access solutions. We carry out an evaluation study of the proposed solution to assess its performance with respect to different system and scenario parameters; the obtained results show that the proposed solution is feasible, capable of providing satisfactory performance, and suitable for implementation in real systems. View full abstract»

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  • On the Cyclostationarity of OFDM and Single Carrier Linearly Digitally Modulated Signals in Time Dispersive Channels: Theoretical Developments and Application

    Publication Year: 2010 , Page(s): 2588 - 2599
    Cited by:  Papers (19)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2738 KB) |  | HTML iconHTML  

    Previous studies on the cyclostationarity aspect of orthogonal frequency division multiplexing (OFDM) and single carrier linearly digitally modulated (SCLD) signals assumed simplified signal and channel models or considered only second-order cyclostationarity. This paper presents new results concerning the cyclostationarity of these signals under more general conditions, including time dispersive channels, additive Gaussian noise, and carrier phase, frequency, and timing offsets. Analytical closed-form expressions are derived for time- and frequency-domain parameters of the cyclostationarity of OFDM and SCLD signals. In addition, a condition to eliminate aliasing in the cycle and spectral frequency domains is derived. Based on these results, an algorithm is developed for recognizing OFDM versus SCLD signals. This algorithm obviates the need for commonly required signal preprocessing tasks, such as signal and noise power estimation and the recovery of symbol timing and carrier information. View full abstract»

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The IEEE Transactions on Wireless Communications publishes high-quality manuscripts on advances in the state-of-the-art of wireless communications.

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Editor-in-Chief
Jeff Andrews
Cullen Trust for Higher Education Endowed Professor of Engineering