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One of the most relevant performance measures in detection problems is the pair of Kullback-Leibler divergences between the densities of the observations under the two hypotheses. In this work, the problem of space-time code design for a multiple-input, multiple-output detection systems is addressed, and the set of achievable divergence pairs is characterized when different constraints are imposed...
Multiple-input-multiple-output (MIMO) radar with collocated antennas transmits orthogonal waveforms to allow the received echoes to be used efficiently for range and Doppler estimation. The orthogonality of the transmitted waveforms should hold for both time shifts and frequency shifts. This paper, for the first time, extends two time-frequency hopping coding methods — the Costas Array Coding (CAC)...
This paper studies linear beamforming based on the generalized singular value decomposition (GSVD) for the two-receiver multiple-input multiple-output (MIMO) Gaussian broadcast channel with confidential messages. The transmitter has two independent messages, each of which is intended for one of the receivers but needs to be kept as secret as possible from the other. Recently, it has been proved that,...
A novel user relaying scheme based on bit concatenation is proposed for a two-user multiple input multiple output(MIMO) broadcast channel (BC). In broadcasting phase, a part of information for a destination user is concatenated to data for a relaying user and transmitted to a relaying user. The destination user receives the part of information via the relaying user in relaying phase in addition to...
Multi-input multi-output (MIMO) systems with orthogonal frequency division multiplexing (OFDM), cooperative communication and three-dimensional (3-D) video coding are state-of-the-art techniques. The combination between cooperative and MIMO systems is crucial to provide high data rates with high quality of 3-D video services. By taking their advantages, this paper presents 3-D video transmission over...
Long Term Evolution (LTE) is emerging as a major candidate for 4G cellular networks to satisfy the increasing demands for mobile broadband services, particularly multimedia delivery. MIMO (Multiple Input Multiple Output) technology combined with OFDMA and more efficient modulation/coding schemes (MCS) are key physical layer technologies in LTE networks. However, in order to fully utilize the benefits...
This paper presents a practical scheme to exploit opportunistic multiuser multiple-input multiple-output (MU-MIMO) diversity in multicarrier systems using orthogonal frequency division multiplexing. The scheme is based on a multi-carrier user selection algorithm to schedule the users that should transmit simultaneously and a fast link adaptation (FLA) technique that, in light of the instantaneous...
Antenna selection technology in MIMO diversity system can achieve almost the same diversity gain as omni-directional antenna without increasing the radio frequency link in system. Several drawbacks exist in commonly used diversity reception method since it only considers the intensity fading of signal rather than content analysis and comparison of signal. In this paper, we study the current wireless...
This paper investigates joint complex diversity coding (CDC) and error control coding (ECC) to increase diversity gains across multiple antennas, OFDM blocks, and OFDM sub-carriers. A general diversity analysis for joint CDC and ECC based space-time-frequency codes (STFCs) is provided. The mapping designs from ECC to CDC are crucial for efficient exploitation of the diversity potential. This paper...
This paper proposes a new space-time coding scheme for non-coherent MIMO systems. In this scheme, called Matrix Coded Modulation (MCM), a joint channel error-correcting code and space-time code is considered. Coherent systems are those for which Channel State Information (CSI) is available at the transmitters and/or at the receivers, and their performance strongly depend on the channel estimation...
The problem of multicasting common data to several users over multiple-input multiple-output (MIMO) Gaussian channels is studied. A closed-loop setup is considered where the channel matrices are known to the transmitter and respective receivers. An incremental-redundancy (rateless) scenario is considered, where the effective rate is measured by the time that each user needs to stay online until it...
Several diversity combining techniques have been proposed for multiple-input multiple-output (MIMO) systems, but only isolated performance comparisons have been reported. In this paper, we aim at comparing three MIMO schemes using selection combining (SC), maximal ratio combining (MRC) and switch-and-stay combining (SSC). It is analytically demonstrated that all the systems achieve full diversity...
this paper proposes a new cascaded scheme for the asynchronous MIMO systems. In the scheme, the LDPC code without girth-4 and STBC code with guard intervals were employed. The cascaded code is capable to reduce the error rate and improve the performance of transmission, by taking advantage of both LDPC and STBC techniques. What's more, this paper adopted the linear dispersion structure to achieve...
An adaptive coding scheme for spectral efficiency improvement in eigen-MIMO is presented. It uses Reed-Solomon (RS) codes with non-adaptive QAM. Non-adaptive modulation is of interest since it reduces the high complexity - in both the electronics and the protocol - required for deploying the more commonly treated adaptive modulation. RS codes have practical advantages in terms of their algorithmic...
This paper addresses a novel Alamouti coding scheme for asynchronous cooperative communication systems over frequency selective fading channels. In the proposed scheme, the Alamouti coded form at the destination node is constructed through a simple combination of symbols at the source node, instead of the time-reversal operation at the relay nodes used in the conventional scheme. Numerical results...
In this paper, we focus on increasing the throughput and diversity of network coded MIMO transmissions in bidirectional multi-pair wireless relay networks. All nodes have multi-antenna capability. Pairs of nodes want to exchange messages via a relay having multi-antenna and encoding/decoding capability. Nodes transmit their messages to the relay in the first (MAC) phase. The relay decodes all the...
Spatial multiplexing is an efficient transmission technique for video streaming in multiple-input multiple-output (MIMO) wireless communication links due to its capability to support the high transmit rate. Nevertheless, the video quality is sensitive to packet losses resulting from channel fading and co-interference between transmit antennas in spatial multiplexing systems. Antenna selection techniques...
Cooperative relay networks with multiple antennas at each node enable achieving both macro diversity and micro diversity in a wireless fading channel. Using beamforming along with space-time (ST) coding at the source and the relay of a cooperative relay network allows achieving both diversity gain and array gain. In this paper we propose novel distributed beamforming techniques for a space-time (ST)...
Construction and application of a neural prosthesis device that enhances existing and replaces lost memory capacity in humans is the focus of research described here in rodents. A unique approach for the analysis and application of neural population firing has been developed to decipher the pattern in which information is successfully encoded by the hippocampus where mnemonic accuracy is critical...
Orthogonal frequency division multiplexing (OFDM) is an attractive technique for wireless communication applications. The principal design problem encountered in wireless communications is how to overcome the distortion of received signals by a time-varying and frequency-selective propagation path due to the phenomenon called fading. Also, a well known problem of OFDM that is the casual occurrence...
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