IEEE Final Year Projects 2011-2012 :: Elysium Technologies Pvt LtdIEEE projects, final year projects, students project, be project, engineering projects, academic project, project center in madurai, trichy, chennai, kollam, coimbatore
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Elysium Technologies Private Limited ISO 9001:2008 A leading Research and Development Division Madurai | Chennai | Trichy | Coimbatore | Kollam| Singapore Website: elysiumtechnologies.com, elysiumtechnologies.info Email: [email protected]IEEE Final Year Project List 2011-2012 Madurai Elysium Technologies Private Limited 230, Church Road, Annanagar, Madurai , Tamilnadu – 625 020. Contact : 91452 4390702, 4392702, 4394702. eMail: [email protected]Trichy Elysium Technologies Private Limited 3 rd Floor,SI Towers, 15 ,Melapudur , Trichy, Tamilnadu – 620 001. Contact : 91431 - 4002234. eMail: [email protected]Kollam Elysium Technologies Private Limited Surya Complex,Vendor junction, kollam,Kerala – 691 010. Contact : 91474 2723622. eMail: [email protected]A b s t r a c t COMMUNICATION 2011 - 2012 01 Future Simplification of Procedure for Decoding Nonsystematic Reed-Solomon Codes Using the Berlekamp-Massey Algorithm It is well-known that the Euclidean algorithm can be used o find the systematic errata-locator polynomial and the errata- evaluator polynomial simultaneously in Berlekamp’s key equation that is needed to decode a Reed-Solomon (RS) codes. In this paper, a simplified decoding algorithm to correct both errors and erasures is used in conjunction with the Euclidean algorithm for efficiently decoding nonsystematic RS codes. In fact, this decoding algorithm is an appropriate modification to the algorithm developed by Shiozaki and Gao. Based on the ideas presented above, a fast algorithm described from Blahut’s classic book is derivated and proved in this paper to correct erasures as well as errors by replacing the Euclidean algorithm 1
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Elysium Technologies Private Limited ISO 9001:2008 A leading Research and Development Division Madurai | Chennai | Trichy | Coimbatore | Kollam| Singapore Website: elysiumtechnologies.com, elysiumtechnologies.info Email: [email protected]
01 Future Simplification of Procedure for Decoding Nonsystematic Reed-Solomon Codes Using the Berlekamp-Massey Algorithm
It is well-known that the Euclidean algorithm can be used o find the systematic errata-locator polynomial and the errata-
evaluator polynomial simultaneously in Berlekamp’s key equation that is needed to decode a Reed-Solomon (RS) codes. In
this paper, a simplified decoding algorithm to correct both errors and erasures is used in conjunction with the Euclidean
algorithm for efficiently decoding nonsystematic RS codes. In fact, this decoding algorithm is an appropriate modification to
the algorithm developed by Shiozaki and Gao. Based on the ideas presented above, a fast algorithm described from Blahut’s
classic book is derivated and proved in this paper to correct erasures as well as errors by replacing the Euclidean algorithm
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by the Berlekamp-Massey (BM) algorithm. These facts lead to significantly reduce the decoding complexity of the proposed
RS decoder.
02 Analysis and Design of Cooperative BICM-OFDM Systems
In this paper, we propose a novel cooperative diversity scheme for wireless systems employing the combination of bit–
interleaved coded modulation (BICM) and orthogonal frequency division multiplexing (OFDM). The proposed scheme utilizes
an amplify–and–forward protocol where relays are assigned to multiple groups. Relays in the same group transmit
concurrently over disjoint sets of sub–carriers and relays in different groups transmit in different time slots. We derive
closed– form expressions for the asymptotic worst–case pairwise error probability and the diversity gain of the proposed
cooperative BICM–OFDM scheme. Based on the derived analytical results we develop design guidelines for sub–carrier
allocation, relay grouping, and relay selection. Simulation results corroborate the derived analytical results and confirm the
effectiveness of the developed optimization framework.
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Motivated by the recent concept of Space-Time Shift Keying (STSK), we propose a novel cooperative STSK family, which is
capable of achieving a flexible rate-diversity tradeoff, in the context of cooperative space-time transmissions. More
specifically, we first propose a Coherent cooperative STSK (CSTSK) scheme, where each Relay Node (RN) activates
Decode and- Forward (DF) transmissions, depending on the success or failure of Cyclic Redundancy Checking (CRC). We
invoke a bitto- STSK mapping rule, where according to the input bits, one of the ���� pre-assigned dispersion vectors is
activated to implicitly convey log2 ���� bits, which are transmitted in combination with the classic log2 ℒℒℒℒ-bit modulated
symbol.
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04 Combinatorial Characterization of Interference Coupling in Wireless Systems
We provide a combinatorial characterization of interference coupling in wireless systems, with the intent of obtaining a
better insight into interference coordination and management. We introduce two bipartite graphs, namely the power graph
and interference graph. We utilize these graphs and global dependency matrix containing only binary (0 and 1) entries to
capture the effects of interference coupling in communication systems. We show that the irreducibility of the global
dependency matrix ���� is related to the connectivity of the power graph and the irreducibility of the matrix ������������ is related to
the connectivity of the interference graph. We prove that for strictly positive and strictly log-convex interference functions,
the irreducibility of the matrices ���� and ������������ are necessary and sufficient conditions for the considered utility sets to be
strictly convex.
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05 Comment on “An Exact Performance Analysis of MRC/OSTBC over Generalized Fading Channels
In this comment, it is shown that the semi-numerical algorithm for computation of the ergodic channel capacity, which
has been suggested in the paper cited by the headline above, can be replaced by a closed-form solution – either based on
generalized hypergeometric functions or, in a more concise and elegant approach, on Meijer’s G-function.
06 Cooperation via Trellis Pruning
In this paper introduces a new approach to cooperative communications. Consider two partner nodes that cooperate to
convey their data to a common destination, each transmitting not only its own “local” data but also acting as a relay for
its partner, thereby effecting spatial diversity. In the proposed scheme, each partner multiplexes local data with relayed
data and convolutionally encodes the resulting bitstream prior to transmission; the other partner then uses its knowledge
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of the relayed data to prune edges from the code trellis, thereby decoding at a lower (and more robust) rate. The
destination observes two copies of each source’s data – one transmitted as local information, the other transmitted as
relayed information – and employs iterative decoding to recover the same.
07 Cramér-Rao Lower Bounds of DOA Estimates from Square QAM-Modulated Signals
In this paper, we derive for the first time analytical expressions for the inphase/quadrature (I/Q) non-data-aided (NDA)
Cramér-Rao lower bounds (I/Q NDA CRLBs) of the direction of arrival (DOA) estimates from square quadrature amplitude
(QAM)-modulated signals corrupted by additive white circular complex Gaussian noise (AWCCGN) with any antenna
configuration. Yet the main contribution embodied by this paper consists in deriving for the first time analytical
expressions for the NDA Fisher information matrix (FIM) and then for the stochastic CRLB of the NDA DOA estimates in
the case of square QAMmodulated signals. It will be shown that in the presence of any unknown phase offset (i.e., non-
coherent estimation), the ultimate achievable performance on the NDA DOA estimates holds almost the same
irrespectively of the modulation order. However, the NDA CRLBs obtained in the absence of the phase offset (i.e.,
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coherent estimation) vary, in the high SNR region, from one modulation order to another.
08 Decision-Feedback Differential Detection in Impulse-Radio Ultra-Wideband Systems
In this paper we present decision-feedback differential detection (DF-DD) schemes for autocorrelation-based detection in
impulse-radio ultra-wideband (IR-UWB) systems, a signaling scheme regarded as a promising candidate in particular for
low-complexity wireless sensor networks. To this end, we first discuss ideal noncoherent sequence estimation and
approximations thereof based on block-wise multiple-symbol differential detection (MSDD) and the Viterbi algorithm (VA)
from the perspective of tree-search/trellis decoding. Exploiting relations well-known from tree-search decoding, we are
able to derive the novel decision-feedback differential detection (DF-DD) schemes. A comprehensive comparison with
respect to performance and complexity of the presented schemes in a typical IR-UWB scenario reveals—along with novel
insights in techniques for complexity reduction of the sphere decoder applied for MSDD— that sorted DF-DD achieves
close-to-optimum performance at very low, and in particular constant receiver complexity.
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09 Design and Analysis of Timing Synchronization in Block Transmission UWB Systems
In this paper, timing synchronization in high-rate ultra-wideband (UWB) block transmission systems is investigated. A new
joint timing and channel estimation scheme is proposed for orthogonal frequency division multiplexing (OFDM) and single
carrier block transmission with frequency domain equalization (SC-FDE) UWB systems. The scheme is based on a newly
designed preamble for both coarse timing and the subsequent channel estimation. Despite of the presence of coarse timing
error, the estimated channel impulse response (CIR) is simply the cyclic shifted version of the real CIR, thanks to the unique
structure of the preamble. The coarse timing error (CTE) is then determined from the CIR estimation and used to fine tune
the timing position and the frequency domain equalization coefficients. The proposed scheme saves preamble overhead by
performing joint synchronization and channel estimation, and outperforms existing timing acquisition methods in the
literature in dense multipath UWB channels.
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10 Error-Rate Performance Analysis of Incremental Decode-and-Forward Opportunistic Relaying
In this paper, we investigate an incremental opportunistic relaying scheme where the selected relay chooses to cooperate
only if the source-destination channel is of an unacceptable quality. In our study, we consider regenerative relaying in which
the decision to cooperate is based on a signalto- noise ratio (SNR) threshold and takes into account the effect of the
possible erroneously detected and transmitted data at the best relay. We derive a closed-form expression for the end-to-end
biterror rate (BER) of binary phase-shift keying (BPSK) modulation based on the exact probability density function (PDF) of
each hop. Furthermore, we evaluate the asymptotic error performance and the diversity order is deduced. We show that
performance simulation results coincide with our analytical results.
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11 Filter and Nested Lattice Code Design for MIMO Fading Channels with Side-Information
Linear-assignment Gel’fand-Pinsker coding (LAGPC) is a coding technique for channels with interference known only at the
transmitter, where the known interference is treated as side-information (SI). As a special case of the LA-GPC, dirty paper
coding has been shown to be able to achieve the optimal interference-free rate for SI channels with perfect channel state
information at the transmitter (CSIT). In the cases where only the channel distribution information at the transmitter (CDIT)
is available, LA-GPC also has good (sometimes optimal) performance in a variety of fast and slow fading SI channels. In
this letter, we design filters in the nested lattice based coding to make it achieve the same rate performance as the LA-GPC
in multiple-input multiple-output (MIMO) channels. Compared with the random Gaussian codebooks used in previous
works, our resultant coding schemes have algebraic structures and can be implemented in practical systems. Simulations
in slowfading channels are provided, and near interference-free error performance is obtained. The proposed coding
schemes can serve as the fundamental building blocks to achieve the promised rate performance of MIMO Gaussian
broadcast channels with CDIT or perfect CSIT.
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Abstract—Gaussian frequency shift keying (GFSK) is a promising digital modulation scheme. The design of simple and
high-performance receivers for GFSK systems is a challenging task. In this letter, we develop an optimized differential
GFSK demodulator and investigate the phase wrapping issue in its implementation. Simulation results show bit-error-rate
(BER) performance improvement in comparison with conventional differential demodulators in both AWGN and flat fading
channels. We also compare our proposed demodulator with other existing alternatives in terms of BER performance.
13 Source Per-Tone Transmit Antenna Selection with Phase Precoding for OFDM
If antenna selection in OFDM is done on a pertone basis, the frequency domain can be exploited to achieve very good
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performance. However this means that the channel after antenna selection will have discontinuities in the frequency
domain. In this paper we present a novel phase precoding that ensures that the channel after antenna selection is smooth
enough in the frequency domain for advanced channel estimation. We analyse its performance and show that it is robust to
channel estimation and reciprocity errors.
14 Post-Scheduling SINR Mismatch Analysis for Multiuser Orthogonal Random Beamforming Systems
In this letter, we analyze the post-scheduling SINR mismatch of a multiuser orthogonal random beamforming (ORBF)
system. The mismatch probability is derived for Gaussian broadcast channels with ���� transmit antennas and ���� single-
antenna users. Numerical results are shown to be identical to theoretical results. The probability analysis enables us to
calculate the minimum number of users to satisfy a target mismatch probability. Another way to use the mismatch
probability is to control CQI mismatch handling mechanisms.
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15 Power Allocation in Spectrum Sharing Cognitive Radio Networks with Quantized Channel Information
We consider a wideband spectrum sharing system where a secondary user can access a number of orthogonal frequency
bands each licensed to a distinct primary user. We address the problem of optimum secondary transmit power allocation for
its ergodic capacity maximization subject to an average sum (across the bands) transmit power constraint and individual
average interference constraints on the primary users. The major contribution of our work lies in considering quantized
channel state information (CSI)(for the vector channel space consisting of all secondary-to-secondary and secondary-
toprimary channels) at the secondary transmitter as opposed to the prevalent assumption of full CSI in most existing work. It
is assumed that a central entity called a cognitive radio network manager has access to the full CSI information from the
secondary and primary receivers and designs (offline) an optimal power codebook based on the statistical information
(channel distributions) of the channels and feeds back the index of the codebook to the secondary transmitter for every
channel realization in real-time, via a delay-free noiseless limited feedback channel. A modified Generalized Lloyds-type
algorithm (GLA) is designed for deriving the optimal power codebook, which is proved to be globally convergent and
empirically consistent. An approximate quantized power allocation (AQPA) algorithm is presented, that performs very close
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to its GLA based counterpart for large number of feedback bits and is significantly faster.
16 Relay Selection from a Battery Energy Efficiency Perspective
The battery nonlinearity has never been considered for energy analysis in relay networks. In this letter, we adopt the realistic
nonlinear battery model, apply the battery energy consumption results in [1] to general relay networks, investigate the
optimum and suboptimum energy allocation solutions for relaying transmission, and establish the relay selection criterion
from the battery energy efficiency perspective. Our analyses and comparisons show that relaying does not always increase
the system energy efficiency. We further establish closed-form conditions that can be easily checked to determine whether
the relay transmission is preferable to the direct transmission. Numerical examples are also presented to verify these
results.
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17 Stability and Distributed Power Control in MANETs with Per Hop Retransmissions
In the current work the effects of hop-by-hop packet loss and retransmissions via ARQ protocols are investigated within a
Mobile Ad-hoc NET-work (MANET). A success probability function is related to each link, which can be controlled by power
and rate allocation. The expression for the network’s stability region is initially derived where the success function plays a
critical role. The investigation considers functions with specific properties which are shown to be satisfied for various
expressions of the success probability related to different modulation and coding schemes as well as outage events. A
Network Utility Maximization problem (NUM) with stability constraints is further formulated which decomposes into the input
rate control and the scheduling problem. Under certain assumptions the latter is relaxed to a simpler form. This allows
application of supermodular game theory and the algorithmic approach in [1] is adapted to include the family of success
functions of interest. It is shown finally that interference measurements per node drastically reduce the amount of
information exchange required for solving the scheduling problem.
.
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18 Turbo Coded Noncoherent Space-Time Modulation Using Information-Bearing Pilots and Spatial Multiplexing
In this paper, we present a turbo coded spacetime modulation scheme for noncoherent block fading channels, where neither
the transmitter nor the receiver knows the channel state information. The turbo coded bits are divided into two parts which are
respectively transmitted through informationbearing pilots and spatial multiplexing (SM). Since this approach effectively
increases the cardinality of the set of possible transmit (space-time) signal matrices, a large rate gain can be obtained without
increasing the modulation order, as shown through achievable-rate analysis. At the receiver, an iterative detectiondecoding
algorithm is performed cooperatively among the turbo decoder, the coherent demapper for the SM, and the noncoherent
demapper for the information-bearing pilots through the help of the proposed signal matrix detector, which enables these two
demappers to utilize the channel information inherent in all the received symbols within the same fading block. Compared to
the previous work in the literature, the proposed scheme can provide advantages in both error performance and complexity.
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19 ZF Detectors over Correlated ���� Fading MIMO Channels
This paper provides a systematic characterization of Zero-Forcing (ZF) detectors over multiple-input multiple-output (MIMO)
channels that experience both small and large-scale fading. In particular, we consider the generic ���� distribution
(Rayleigh/gamma distribution) to model the composite fading fluctuations and also assume the general case of semi-
correlated small-scale fading. In the following, novel exact analytical expressions for the achievable sum rate are derived,
followed by asymptotic expressions in the high and low Signal-to-Noise ratio (SNR) regimes. In these limiting cases, two
common and insightful affine expansions are studied followed by new, closedform upper and lower bounds on the sum rate
that remain tight for all SNRs. In the second part of the paper, we present exact tractable expressions along with first-order
expansions for the symbol error rate (SER) and outage probability; we also quantify the performance of ZF detectors in
terms of diversity order and array (or coding) gain. The implications of the model parameters on the ZF detector performance
are investigated via Monte-Carlo simulations which also validate the theoretical analysis
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20 High-SNR Performance of MIMO Multi-Channel Beamforming in Double-Scattering Channels
This paper investigates the symbol error rate (SER) performance of the multiple-input multiple-output (MIMO) multi-channel
beamforming (MB) in the general doublescattering channel. We derive an asymptotic expansion on the marginal eigenvalue
distribution of the MIMO channel matrix, and apply the result to get an approximate expression on the average SER at high
signal-to-noise ratio (SNR). Two parameters pertaining to the SER, i.e., the diversity gain and the array gain, are analyzed.
Our results show that it suffices for the doublescattering channel to have only limited scatterers, if the same diversity gain
as the Rayleigh channel is desired; however, once the number of scatterers is below a certain level, the array gain in the
double-scattering channel will vary with the SNR logarithmically.
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21 Hybrid ARQ Protocol for Multi-Antenna Multicasting Using a Common Feedback Channel
Wireless multicasting (also called common information broadcasting) is a technique where a common information message
is transmitted to multiple users. This is typically accomplished by having the basestation broadcast out a signal
representing this message. In this paper, we consider a multicasting scheme where the basestation transmits the
multicasting signal without any a-priori knowledge of the users’ channel state information. In this set-up, a hybrid automatic
repeat request (ARQ) control is employed to improve the reliability of multicasting communication. In most hybrid ARQ set-
ups, each user is usually allocated a dedicated feedback channel to tell the basestation if the previously transmitted signal
was correctly decoded. However, dedicated feedback channels waste significant uplink resources, especially when the
number of users is large. To mitigate this problem, we consider a negative acknowledgement (NACK) based hybrid ARQ
control where the failed users are allowed to transmit the NACK signal (which is assumed to be the same for all users)
through a common channel while the other users remain silent. We consider the effect of feedback error and multicasting
signal decoding error on our hybrid ARQ system performance as the number of users grows large. Specifically, it is shown
that the throughput performance of the proposed hybrid ARQ scheme using repetition retransmission is not severely
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degraded relative to the throughput performance of the noiseless feedback case. In addition, we show that the performance
improvement obtained by replacing repetition encoding with incremental redundancy becomes insignificant for the large
number of users asymptote. On the other hand, it is shown that the improvement provided by incremental redundancy is
significant when some of the users are allowed to fail to decode the message.
22 Intermodulation Distortion in Multicarrier Satellite Systems: Analysis and Turbo Volterra Equalization
The urgent objective of transmitting high data rates over satellite, coupled with the challenge to maximize satellite mass
efficiency, has necessitated that multiple carriers share the same transponder high-power amplifier (HPA). This paper
presents analytical framework that characterizes the resulting intermodulation distortion (IMD) by utilizing Volterra series
representation to account for the memory within the carrier itself and those associated with other carriers. Also provided is
analytical evaluation of nonlinear IMD which involves computing statistical averages of higher-order products of Volterra
series containing complex-valued symbols from multiple carriers. Using this theoretical characterization, novel algorithms
are developed to overcome IMD in highly distortion-limited environments by employing the powerful Turbo equalization
method with linear minimum mean-squared error criterion. Further, the solution is adaptive so compensation does not
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require prior knowledge of the HPA characteristics and can be rapidly responsive to variations in the environment. Through
extensive simulations, it is shown that the proposed multicarrier analysis and Turbo Volterra techniques can be used to
substantially remove IMD resulting from operating the nonlinear transponder HPA, shared by multiple carriers, near
saturation. By applying more iterations of joint equalization and decoding, the solution can approach the ideal performance
when feeding back correct decisions.
23 On Cubic Metric Reduction in OFDM Systems by Tone Reservation
One of the major drawbacks of multicarrier modulation is the large envelope fluctuations which either requires an inefficient
use of high power amplifiers (HPAs) or decreases the system performance. Peak-to-average power ratio (PAPR) is the best
known measure of the envelope fluctuations and is widely employed to design multicarrier systems. However, recently,
another metric known as cubic metric (CM), is being considered in several multicarrier systems since it can predict HPA
power de-rating more accurately. In this paper tone reservation (TR) technique, originally used for PAPR-reduction, is
reformulated to reduce CM. We first simplify CM to define the objective function, denoted as objective CM (OCM). Then we
demonstrate that OCM is convex and formulate TR for CM-reduction as an unconstrained convex optimization problem. The
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solution to this problem is found by means of an iterative algorithm which approaches the optimal solution with few steps. In
this paper a low-complexity suboptimal algorithm capable of approaching the optimum with sufficient accuracy is also
proposed. Simulation results show that for similar computational complexity, the performance of CMreduction is superior to
that of PAPR-reduction both in terms of bit error rate and out-of-band leakage.
24 On Outage Probability and Diversity-Multiplexing Tradeoff in MIMO Relay Channels
Fading MIMO relay channels are studied analytically, when the source and destination are equipped with multiple antennas
and the relays have a single one. Compact closed-form expressions are obtained for the outage probability under i.i.d. and
correlated Rayleigh-fading links. Low-outage approximations are derived, which reveal a number of insights, including the
impact of correlation, of the number of antennas, of relay noise and of relaying protocol. The effect of correlation is shown to
be negligible, unless the channel becomes almost fully correlated. The SNR loss of relay fading channels compared to the
AWGN channel is quantified. The SNR-asymptotic diversity-multiplexing tradeoff (DMT) is obtained for a broad class of
fading distributions, including, as special cases, Rayleigh, Rice, Nakagami, Weibull, which may be non-identical, spatially
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