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179
Unitary SpaceTime Modulation for MultipleAntenna Communications in Rayleigh Flat Fading
 IEEE Trans. Inform. Theory
, 1998
"... Motivated by informationtheoretic considerations, we propose a signalling scheme, unitary spacetime modulation, for multipleantenna communication links. This modulation is ideally suited for Rayleigh fastfading environments, since it does not require the receiver to know or learn the propagation ..."
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Cited by 307 (19 self)
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Motivated by informationtheoretic considerations, we propose a signalling scheme, unitary spacetime modulation, for multipleantenna communication links. This modulation is ideally suited for Rayleigh fastfading environments, since it does not require the receiver to know or learn the propagation coefficients. Unitary spacetime modulation uses constellations of T \cross M spacetime signals {\Phi_l, l= 1,...L},where T represents the coherence interval during which the fading is approximately constant, and M > M . We design some multipleantenna signal constellations and simulate their effectiveness as measured by bit error probability with maximum likelihood decoding. We demonstrate that two antennas have a 6dB diversity gain over one antenna at 15db SNR.
A differential detection scheme for transmit diversity
 IEEE J. Select. Areas Commun
, 2000
"... Abstract—We present a transmission scheme for exploiting diversity given by two transmit antennas when neither the transmitter nor the receiver has access to channel state information. The new detection scheme can use equal energy constellations and encoding is simple. At the receiver, decoding is a ..."
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Cited by 212 (7 self)
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Abstract—We present a transmission scheme for exploiting diversity given by two transmit antennas when neither the transmitter nor the receiver has access to channel state information. The new detection scheme can use equal energy constellations and encoding is simple. At the receiver, decoding is achieved with low decoding complexity. The transmission provides full spatial diversity and requires no channel state side information at the receiver. The scheme can be considered as the extension of differential detection schemes to two transmit antennas. Index Terms—Antenna arrays, differential detection, spacetime codes, transmitter diversity. I.
Efficient Use of Side Information in MultipleAntenna Data Transmission over Fading Channels
, 1998
"... We derive performance limits for two closely related communication scenarios involving a wireless system with multipleelement transmitter antenna arrays: a pointtopoint system with partial side information at the transmitter, and a broadcast system with multiple receivers. In both cases, ideal be ..."
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Cited by 205 (4 self)
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We derive performance limits for two closely related communication scenarios involving a wireless system with multipleelement transmitter antenna arrays: a pointtopoint system with partial side information at the transmitter, and a broadcast system with multiple receivers. In both cases, ideal beamforming is impossible, leading to an inherently lower achievable performance as the quality of the side information degrades or as the number of receivers increases. Expected signaltonoise ratio (SNR) and mutual information are both considered as performance measures. In the pointtopoint case, we determine when the transmission strategy should use some form of beamforming and when it should not. We also show that, when properly chosen, even a small amount of side information can be quite valuable. For the broadcast scenario with an SNR criterion, we find the efficient frontier of operating points and show that even when the number of receivers is larger than the number of antenna array ...
Multihop diversity in wireless relaying channels
 IEEE Trans. on Communications
"... Abstract—This paper presents theoretical characterizations and analysis for the physical layer of multihop wireless communications channels. Four channel models are considered and developed: the decoded relaying multihop channel; the amplified relaying multihop channel; the decoded relaying multihop ..."
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Cited by 148 (24 self)
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Abstract—This paper presents theoretical characterizations and analysis for the physical layer of multihop wireless communications channels. Four channel models are considered and developed: the decoded relaying multihop channel; the amplified relaying multihop channel; the decoded relaying multihop diversity channel; and the amplified relaying multihop diversity channel. Two classifications are discussed: decoded relaying versus amplified relaying, and multihop channels versus multihop diversity channels. The channel models are compared, through analysis and simulations, with the “singlehop ” (direct transmission) reference channel on the basis of signaltonoise ratio, probability of outage, probability of error, and optimal power allocation. Each of the four channel models is shown to outperform the singlehop reference channel under the condition that the set of intermediate relaying terminals is selected intelligently. Multihop diversity channels are shown to outperform multihop channels. Amplified relaying is shown to outperform decoded relaying despite noise propagation. This is attributed to the fact that amplified relaying does not suffer from the error propagation which limits the performance of decoded relaying channels to that of their weakest link. Index Terms—Adhoc networks, cooperative diversity, diversity techniques, mesh networks, multihop channels, multihop diversity, wireless relaying. I.
A Unified Approach to the Performance Analysis of Digital Communication over Generalized Fading Channels
 Proc. IEEE
, 1998
"... this paper, see [14], [21], [25], [34], and [35] ..."
A New View of Performance Analysis Techniques in Correlated Rayleigh Fading
, 1999
"... This paper provides a new formulation for the pairwise error probability for any coherently demodulated system in Rayleigh fading. The novelty of the result is that the resulting error rate expression is a polynomial function of the eigenvalues of a "signal" matrix. This view also enable ..."
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Cited by 28 (13 self)
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This paper provides a new formulation for the pairwise error probability for any coherently demodulated system in Rayleigh fading. The novelty of the result is that the resulting error rate expression is a polynomial function of the eigenvalues of a "signal" matrix. This view also enables a simple new asymptotically tight bound on the pairwise error probability. Examples of single and multiple transmit antenna systems are considered. Keywords Diversity, Rayleigh Fading, Performance Analysis, Spacetime Coding I. Introduction Performance analysis of digital communications systems in fading channels has been an area of longtime interest. Results were first obtained in [1]. An elegant unified technique was presented in [2], [3] for signals experiencing complex Gaussian fading and advanced textbooks have significant sections discussing related results [4]. Improvements and generalizations continued to be derived through the current time (e.g., [5]). An extensive bibliography of imp...
Performance enhancement through joint detection of cochannel signals using diversity arrays
 IEEE Trans. Commun
, 1998
"... ..."
Analysis of hybrid selection/maximalratio diversity combiners with Gaussian errors
 IEEE Trans. Wireless Commun
, 2002
"... Abstract—The paper examines the impact of Gaussian distributed weighting errors (in the channel gain estimates used for coherent combination) on both the output statistics of a hybrid selection/maximalratio (SC/MRC) receiver and the degradation of the average symbolerror rate (ASER) performance a ..."
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Cited by 23 (0 self)
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Abstract—The paper examines the impact of Gaussian distributed weighting errors (in the channel gain estimates used for coherent combination) on both the output statistics of a hybrid selection/maximalratio (SC/MRC) receiver and the degradation of the average symbolerror rate (ASER) performance as compared with the ideal case. New expressions are derived for the probability density function, cumulative distribution function and moment generating function (MGF) of the coherent hybrid SC/MRC combiner output signaltonoise ratio (SNR). The MGF is then used to derive exact, closedform, ASER expressions for binary and Mary modulations in conjunction a nonideal hybrid SC/MRC receiver in a Rayleigh fading environment. Results for both selection combining (SC) and maximalratio combining (MRC) are obtained as limiting cases. Additionally, the effect of the weighting errors on both the outage rate of error probability and the average combined SNR is investigated. These analytical results provide insights into the tradeoff between diversity gain and combination losses, in concert with increasing orders of diversity branches in an energysharing communication system. Index Terms—Binary and Mary signaling, coherent combiner with weighting errors, diversity methods, hybrid diversity receivers. I.
Performance Analysis of Compact Antenna Arrays with MRC in Correlated Nakagami Fading Channels
 IEEE TRANS. VEH. TECHNOL
, 2001
"... This paper presents the average error probability performance of a compact space diversity receiver for the reception of binary coherent and noncoherent modulation signals through a correlated Nakagami fading channel. Analytical expressions of the average bit error rate (BER) are derived as a functi ..."
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Cited by 23 (5 self)
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This paper presents the average error probability performance of a compact space diversity receiver for the reception of binary coherent and noncoherent modulation signals through a correlated Nakagami fading channel. Analytical expressions of the average bit error rate (BER) are derived as a function of the covariance matrix of the multipath component signals at the antenna elements. Closedform expressions for the spatial crosscorrelation are obtained under a Gaussian angular power profile assumption, taking account of the mutual coupling between antenna elements. The effects of antenna array configuration (geometry and electromagnetic coupling) and the operating environment (fading, angular spread, mean angleofarrival) on the BER performance are illustrated.
Impact of diversity reception on fading channels with coded modulation. Part III: Cochannel interference
, 1997
"... In previous work we have studied the impact of diversity on coded digital communication systems operating over fading channels. In particular, we have shown that diversity may be thought of as a way of making the channel more similar to a Gaussian one. The present paper extends this analysis to fadi ..."
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Cited by 22 (2 self)
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In previous work we have studied the impact of diversity on coded digital communication systems operating over fading channels. In particular, we have shown that diversity may be thought of as a way of making the channel more similar to a Gaussian one. The present paper extends this analysis to fading channels affected by cochannel interference (CCI). Several receiver models are examined, namely, with ideal coherent detection and perfect channelstate information (CSI), and with differential and pilottone detection. We study the effect of diversity on the irreducible error floor caused by CCI and fading, and the asymptotic behavior of the channel as the diversity order increases. Our results show that, when perfect CSI is available, diversity is able to turn asymptotically the channel into a CCIfree additive white Gaussian noise (AWGN) channel with the same signaltonoise ratio (SNR). On the other hand, for differential and pilottone detection, diversity achieves significant gains ...