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This paper proposes a novel three-dimensional (3D) two-sphere regular-shaped geometry-based stochastic model (RS-GBSM) with only double-bounced rays for non-isotropic scattering narrowband multiple-input multiple-output (MIMO) mobile-to-mobile (M2M) channels. The proposed 3D model has the ability to investigate the joint impact of both the azimuth angle and elevation angle on channel statistics. Based...
In this paper a multi-input multi-output (MIMO) communication system is considered in which a relay with multiple antennas is used to assist the data transmission from the source to destination. We assume that the relay applies a linear transform matrix on its received signal vector and retransmit the transformed vector to the destination node. We optimize the transform matrix by maximizing the average...
Asymptotic capacity and precoding design are presented in the literature for a special case of wireless correlated multi-hop multi-input multi-output (MIMO) networks, where the channel has only white noise at the destination, no noise at all relay levels, and the number of antennas is very large. This particular channel assumption is not always feasible in compact MIMO design with space limitation...
In this paper, we investigate the differential channel state information (CSI) feedback problem for a general multiple input multiple output(MIMO) system over time-correlated Rayleigh block-fading channels. Specifically, we first derive the analytical minimum differential feedback rate in the presence of channel estimation errors and quantization distortion. With the feedback-channel capacity constraint,...
This paper proposes a geometry-based statistical model for multiple-input multiple-output shallow water wireless channels. From the reference model, the corresponding space-time-frequency correlation function and space-Doppler power spectral density are derived. To verify our results, the derived statistics are compared with the experimentally obtained channel statistics and close agreement is observed.
We investigate non-coherent multi-input multi-output (MIMO) signal processing which requires no channel state information (CSI) at either the transmitter or the receiver. With non-coherent codes on Grassmann manifold, a receiver employing generalized likelihood ratio test (GLRT) algorithm offers the maximum-likelihood performance even without CSI. However, the conventional GLRT suffers from a severe...
TCH (Tomlinson, Cercas and Hughes) sequences have been studied for code-spreading and channel coding, but their true purpose is for synchronization and channel estimation. This is due to their property of being (virtually) orthogonal to all of their sequences obtained via circular shifts, and the use of the FFT (Fast Fourier Transform) for decoding. This property is extremely useful for time-offset...
This paper investigates a Slotted ALOHA protocol for a multi-user wireless system operating under partial Line of Sight (LOS) conditions in which both the base station and mobile users are equipped with multiple element antennas. The investigations focus on how physical layer parameters such as spatial correlation, mutual coupling and Rician factor K affect the system capacity. Probability model for...
Two numerical approaches, the Robust-Generalized Iterative Approach (R-GIA) and the Robust-Transmit Covariance Optimization Approach (R-TCOA), are proposed for jointly designing the minimum mean square error (MMSE) precoders and decoders of uplink multiuser multiple-input-multiple-output (MIMO) systems with arbitrary linear equality power constraints and possibly imperfect channel state information...
Multiple-input multiple-output (MIMO) channel sounding measurements were conducted in a typical indoor line-of-sight (LOS) office room environment in Harbin Institute of Technology Shenzhen Graduate School and the results of spatial correlation under different polarization patterns were analyzed. The measurement campaign at a frequency of 2.45G using 4×4 MIMO structure was carried out in order to...
This paper proposes a three dimensional channel model for the study of distributed MIMO communication systems, where the transmit antennas may be at different directions when viewed from the receiver. Examples of such systems include cooperative satellites and air based base stations. Both line of sight and multipath signal components are considered. A common difficulty of such channel models is that...
We experimentally measure and characterize the channel fluctuations in a terrestrial laser communication link using spatial diversity. We measure the signals arising from the propagation of laser beams in a system that comprises two transmit and two receive apertures under various design settings. We find that the spatial channels are statistically correlated. This spatial correlation increases with...
We design non-codebook-based Multiple-Input Multiple-Output (MIMO) precoding schemes using multiple cell-specific reference signals patterns for the time division duplex (TDD) mode of LTE, where channel reciprocity can be exploited. Previously proposed non-codebook-based precoding schemes typically use UE specific reference signals for demodulation. Cell specific reference signals are however always...
In this paper, we investigate the impact of the transmit spatial correlation on the performance of the spatial multiplexing Multiple-Input Multiple-Output (MIMO) Multi-User (MU) Ultra-WideBand (UWB) system in which a pre-equalizer and a Time Reversal (TR) pre-filter are deployed at the transmitter. The combination of the pre-equalizer and the pre-filter is to mitigate the Multiple-Stream Interference...
In this paper, we present a new method for the design of ergodic sum-of-sinusoids (SOS) simulation models for multiple uncorrelated Rayleigh fading channels. The method, which is intended for a special class of SOS models, known as sum-of-cisoids (SOC) models, can be used to generate an arbitrary number of uncorrelated Rayleigh fading waveforms with specified Doppler power spectral characteristics...
With the advances of multiple input multiple output (MIMO) technology as one of IMT-Advanced features, it has become feasible to adopt the technology into the mobile location scenario. By exploiting the multipath characteristics of the MIMO system, it is possible to estimate the position of mobile stations (MS) by considering the capability of MIMO to mitigate the non line of sight (NLOS) conditions...
This paper considers a channel estimation scheme for a two-hop non-regenerative MIMO relay system. The scheme has two phases. In the first phase, the source node transmits no signal, the relay transmits a training matrix and the destination estimates the relay-to-destination channel matrix. In the second phase, the source transmits a training matrix, the relay amplifies and forwards with a relay transformation...
In this paper, we design a new class of cross-layer opportunistic channel access scheduling framework for multiple-input multiple-output (MIMO) networks through exploitation of channel distribution information (CDI) in a form of full spatial correlation matrix. Due to propagation delay, infrequent channel updates, and time-varying node position, channel knowledge becomes outdated and scheduler based...
We derive a spherical linear interpolation (SLI) with a closed-form phase term. The derived SLI is compared with the geodesic interpolation. Simulation results show that both schemes are efficient and similar when the channels are highly correlated, since their objectives are equivalent in a sense of minimizing the distance between two adjacent codewords.
To reduce the severe performance degradation of the traditional antenna selection schemes in correlated Multiple-Input Multiple-Output (MIMO) channels, this paper proposes a new antenna selection scheme via an improved particle swarm optimization (IMPSO) algorithm. IMPSO algorithm increases the rank of the correlated fading channel matrix. These increments, directly, contribute to the Effective Degree...
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