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We study the high-SNR capacity of MIMO Rayleigh block-fading channels in the noncoherent setting where neither transmitter nor receiver has a priori channel state information. We show that when the number of receive antennas is sufficiently large and the temporal correlation within each block is “generic” (in the sense used in the interference-alignment literature), the capacity pre-log is given by...
DS-CDMA featuring asynchronous multiple access, robustness to frequency selective fading and multipath combining is chosen as air interface standard in WCDMA. WCDMA works with 5MHz and chip rate of 3.84Mcps. As it supports variable spreading factor to achieve flexible data rate, during high transmission rate uses short spreading code. But users with these smaller spreading codes may experience inter-path...
In the moving turbulent ocean, the irradiance fluctuation may depend on both the position and time. In this paper, we investigate temporal statistics of irradiance in the moving ocean with weak turbulence. We present a closed-form expression for the relationship of temporal correlation, propagation distance, and average velocity for the moving medium. We then evaluate the temporal correlation of irradiance...
Large-scale multi-cell multiuser multiple-input multiple-output (LS-MIMO) systems can greatly increase the spectral efficiency. But the performance of these systems is deteriorated by pilot contamination. In this paper, first, a pilot design criterion is proposed by exploiting the orthogonality of channel vectors of LS-MIMO systems. Second, following this criterion, Chu sequences based pilots are...
Owing to ideal correlation properties of complementary codes (CCs), a complementary coded code division multiple access (CC-CDMA) system outperforms traditional CDMA systems in terms of its interference resistance in both synchronous and asynchronous transmissions. This paper shows that a normal CC-CDMA system loses its interference-free feature over uplink frequency selective fading channels due...
We address the distributed estimation of an unknown scalar parameter in Wireless Sensor Networks (WSNs). Sensor nodes transmit their noisy observations over multiple access channel to a Fusion Center (FC) that reconstructs the source parameter. The received signal is corrupted by noise and channel fading, so that the FC objective is to minimize the Mean-Square Error (MSE) of the estimate. In this...
Antenna correlation is usually viewed as a detrimental effect in a multiple input multiple output (MIMO) system. This paper investigates how this affects the performance of an amplify-and-forward (AF) relay network. We consider multiple antennas at all nodes with a general correlation matrix structure having an arbitrary eigenvalue distribution. We derive exact closed form expression for the ergodic...
In this paper, we investigate the performance of cooperative decode-and-forward (DF) multiple-input multiple-output (MIMO) relaying system with orthogonal space-time block code (OSTBC) transmissions over correlated Nakagami-m fading channels. For maximal ratio combining (MRC) receiver at the destination, we provide the compact closed-form expressions for cumulative distribution function (CDF) and...
Exact error rate analysis for pre-detection equal gain combining over arbitrarily correlated fading branches has proven elusive. Even specialized correlation models result in complex error rate expressions with multiple nested infinite series or integrals. For this reason, asymptotic analysis is a useful tool due to the simplicity of the error rate expressions it produces. However, one major shortcoming...
In this paper, we analyse the performance of a single-relay cooperative diversity system, which is an effective technique to combat the effects of small scale fading, in a more realistic scenario by assuming a correlation among source-to-relay (SR), relay-to-destination (RD), and source-to-destination (SD) links. A generalised closed form end-to-end symbol error probability (SEP) expression for M-ary...
We present a general upper bounding framework for the average bit error probability (ABEP) of generalized spatial modulation (G-SM) over correlated Rayleigh and Rician channels. Our approach is applicable to any multiple-input multiple-output (MIMO) configuration and linear modulation alphabet. The framework also incorporates possibly correlated Gaussian channel estimates. The ABEP with perfect channel...
Coordinated multi-point transmission (CoMP) is a promising strategy to provide high spectral efficiency for cellular systems. To facilitate multicell precoding, downlink channel is estimated via uplink training in time division duplexing systems by exploiting channel reciprocity. Virtual subcarriers in practical orthogonal frequency division multiplexing (OFDM) systems degrade the channel estimation...
We consider a confidential communication through log-normal fading channel in which a single antenna transmitter communicates with a legitimate receiver in the presence of an eavesdropper. Employing maximal ratio combining (MRC) and equal gain combining (EGC) reception schemes at the legitimate receiver and eavesdropper, we find the closed-form expressions for the secrecy parameters, namely, the probability...
Previous works on space-time-frequency (STF) codes have focused on frequency-selective but independent fading channels for MIMO-OFDM systems. However, insufficient antenna space, mobile scenarios, and multipath in practice cause correlation in the spatial, temporal, and frequency domains. This paper studies the effect of STF coding on the performance of MIMO-OFDM systems with general spatial, temporal,...
We present a general framework for the analysis of the effects of channel estimation errors on the average bit error probability (ABEP) of spatial modulation over correlated Rayleigh and Rician channels. The proposed approach is useful in obtaining the upper bound on the ABEP exactly for M-ary PSK constellations and with a very close approximation for M-ary QAM constellations. The framework is applicable...
Bit Error Rate (BER) is a key parameter used to evaluate the performance of radio communication systems. In this paper, a realistic BER of radio MRC diversity systems is predicted based on the Multi-Resolution Frequency Domain ParFlow (MR-FDPF) model. The prediction takes into account the correlations among diversity branches and makes no assumptions of the correlation model. The predicted realistic...
The accuracy of wireless network packet simulation critically depends on the quality of the wireless channel models. These models directly affect the fundamental network characteristics, such as link quality, transmission range, and capture effect, as well as their dynamic variation in time and space. Path loss is the stationary component of the channel model affected by the shadowing in the environment...
Indoor localization is one key element in current and future mobile applications and services. Based on the estimate of ranges between the mobile user and anchors, like base stations or access points, and between mobile users in the cooperative context, geolocation algorithms must be robust in crowded and multipath-rich indoor environments. Channel models play a fundamental role in the validation...
In the view of the appropriateness of the K fading channels for characterizing the wireless communication links, this paper inspects the outage probability and corresponding capacity of such a composite channel model. Differing from the traditional outage definition, we consider the time correlation to describe the real outage occurrences in the mobile network deployments. For more, the fade duration...
In wireless orthogonal frequency division multiplexing (OFDM) systems in order to reduce channel impairments, and increase system performance channel estimation must be implemented. This paper investigates; the impact on channel estimation mean squared error (MSE) performance of pilot density and placement for the channels that have different time variant transfer function. The time and frequency...
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