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This paper derives an exact closed-form expression for the phase-envelope joint distribution of the kappa-mu fading environment, a general fading model that includes the Rice and the Nakagami-m models as special cases. The derived joint statistics are obtained so that compatibility with both Rice as well as Nakagami-m cases are kept. Monte Carlo simulations are used to validade the formulations.
In this paper, we analyze the capacity of orthogonal frequency division multiplexing (OFDM) systems with carrier frequency offset (CFO) in frequency-selective Nakagami-m fading channels. Previous work on this topic has not taken into account the frequency selectivity of the channel. In this work, we have explicitly attributed the effect of channel frequency selectivity, i.e. frequency domain correlations,...
In this paper we investigate the performance of the Parity Bit selected Multicarrier Direct Sequence Spread Spectrum (PB-MC-DS-SS) system using Log Likelihood Ratio (LLR). In this system information bits are convolutionally encoded prior to being used in the parity bit selected MC-DS-SS system. Reliability of the detected bits in the receiver is calculated in the form of LLRs and then used as the...
In a three-node wireless relay network, two nodes, BS1 and BS2, exchange information through a relay node, RL. Suppose time division duplex is used, physical network coding (PNC) uses two time slots for the information exchange instead of four time slots needed by the conventional method. In the first time slot, both BS1 and BS2 transmit simultaneously to RL. The relay node, RL does a PNC mapping...
In this paper, we extend the well-known model for Gaussian Cellular Multiple Access Channel originally presented by Wyner and later extended by Somekh et al. with fading. The extension to the model, incorporates the distance dependent path loss (maintaining a close relevance to path loss values in real world cellular systems) experienced by the users distributed in a planar cellular array. The density...
A low-complexity high performance Rayleigh fading simulator, an ARMA(3,3) model, is proposed. This proposed method is a variant of the method of filtering of the white Gaussian noise where the filter design is accomplished in the analog domain and transferred into digital domain. The proposed model is compared with improved Jakespsila model, autoregressive filtering and IDFT techniques, in performance...
In this paper we propose a new scheme for multi-hop forwarding in wireless networks. This new scheme is based on detection and forwarding of the received messages at the physical layer, without further processing at the higher layers. We derive a new expression for the symbol error rate in this proposed multi-hop detect-and-forward network by modeling the transmission line as a Markov Chain. The derived...
The distribution of the eigenvalues of Wishart matrices and Gaussian quadratic forms is of great interest in communication theory, especially in relation to multiple-input multiple-output (MIMO) systems. In this paper we present some new results on the joint distribution of an arbitrary subset of the ordered eigenvalues of Wishart matrices, using the tensor operator T (.), which was first introduced...
For a distributed multiple input single output (DMISO) system a terminal can be connected to all system antennas, but this leads, obviously, to a high processing capacity requirement, which is not practical. Since capacity increases only slightly with the terminal connection to more antennas, it is important to evaluate the number of antennas that a terminal must be connected to. Thus in this paper...
In this paper, a novel time-of-arrival estimation algorithm is proposed for impulse radio-based UWB systems in dense multipath environment. In particular, a dedicated ranging sequence with good cross-correlation property is proposed and a threshold-based search-back unit is introduced, with the purpose of supporting high-precision ranging even at low signal-to-noise ratio. An approximate closed-form...
Precoded spatial multiplexing multiple-input multiple-output (MIMO) systems using limited feedback have been extensively studied to reduce the feedback information based on the notion of delay-free feedback channel. In order to reduce performance degradation of precoded spatial multiplexing MIMO systems due to delay in the feedback channel, in this paper, we take into account the time varying nature...
Mobile-to-mobile (M2M) fading channels in cooperative networks can efficiently be modeled using the multiple scattering concept. In this paper, we propose a new second-order scattering channel model for M2M fading channels in amplify-and-forward relay links under line-of-sight (LOS) conditions, where the received signal comprises only of the single and double scattered components. In the proposed...
Consider the problem of base-station and sub-carrier assignment on the downlink of a two-cell OFDMA system with adaptive modulation. The aim is to maximize a common data rate that can be offered to each user with a guaranteed maximum rate-outage probability. A target bit-error rate is also guaranteed with a maximum outage probability. The channel model takes into account the propagation path-loss...
Recently, we reported a low-complexity likelihood ascent search (LAS) detection algorithm for large MIMO systems with several tens of antennas that can achieve high spectral efficiencies of the order of tens to hundreds of bps/Hz. Through simulations, we showed that this algorithm achieves increasingly near SISO AWGN performance for increasing number of antennas in i.i.d. Rayleigh fading. However,...
This paper considers the problem of power management and throughput maximization for energy neutral operation when using energy harvesting sensors (EHS) to send data over wireless links. It is assumed that the EHS are designed to transmit data at a constant rate (using a fixed modulation and coding scheme) but are power-controlled. A framework under which the system designer can optimize the performance...
This paper considers quantization and exact minimum mean square error (MMSE) estimation of the squared Frobenius norm and the squared spectral norm of a Rayleigh fading multiple-input multiple-output (MIMO) channel with one-sided spatial correlation. The Frobenius and spectral norms are of great importance when describing the achievable capacity of many wireless communication systems; in particularly,...
Different multiple input - multiple output (MIMO) channel models are analyzed with regard to the indoor line-of-sight (LOS) MIMO channel. In the literature this channel is proven to achieve high capacities while being highly correlated. The modeling results from physical as well as analytical models are compared with measured channels, showing that none of the established models is exactly suitable...
The proportional fair scheduling (PFS) problem is studied in the paper. PFS is considered an attractive bandwidth allocation criterion in wireless networks for supporting high resource utilization while maintaining good fairness among network flows. The most challenge of a PFS problem is the lack of an analytic expression. By rigorously mathematical derivation, we obtain a closed-form expression for...
Proportional fair scheduling (PFS) provides good balance between throughput and fairness via multi-user diversity and game-theoretic equilibrium. Very little analytical work exists on understanding the performance of PFS. Most existing prior results are for networks with Rayleigh fading. In this paper, we provide theoretical results for PFS in general fading environments. The results reveal that the...
In this paper, we investigate the effects of RF impairments and imperfect channel state information (CSI) on the performance of M-QAM orthogonal frequency division multiplexing (OFDM) employing maximum ratio combining (MRC) receiver architecture in Rayleigh fading channels. We derive the BER expressions for M-QAM OFDM with the effects of the RF impairments and employing R-branch MRC receiver structure...
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