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This paper presents a spectrally efficient distributed coded cooperation based on Opportunistic Relaying for multi-relay. The proposed scheme chooses the best relay to participate in the cooperation depending on the instantaneous channel information. We adopt distributed Rate-compatible punctured convolutional code. The relay operates on DF mode. After the single relay has been chosen, the best relay...
In this paper, we present a new results on soft MIMO detection for turbo codes. Proper utilization of soft decision information is one of the important factors affecting the performance of turbo codes. If a spatial multiplexing scheme with multiple antennas is used with turbo codes, the output of the detection process should be soft decision information. In this paper, we present various aspects on...
The problem of transmitting a common message over a multiple-input multiple-output (MIMO) Gaussian broadcast channel with multiple receivers is well understood in terms of capacity. Nevertheless, existing optimal (capacity-achieving) schemes for this scenario require joint decoding of the multiple streams transmitted, entailing high computational complexity. In this paper, a low-complexity scheme...
A multiple-input multiple-output two-way relay channel consisting of two communication nodes and a full-duplex relay node is considered, assuming that no direct link exists between the two communication nodes. We propose an achievable scheme using lattice codes combined with generalized singular value decomposition-based precoding for the first phase and vertically encoded structural bining for the...
We consider the problem of communicating over a multiple-input multiple-output (MIMO) real valued channel for which no mathematical model is specified, and achievable rates are given as a function of the channel input and output sequences known a-posteriori. This paper extends previous results regarding individual channels by presenting a rate function for the MIMO individual channel, and showing...
We investigate the effects of imperfect channel knowledge and feedback in incremental-redundancy automatic-repeat request (INR-ARQ) coding systems over multiple-input multiple-output (MIMO) block-fading channels. We propose an ARQ decoder based on nearest neighbour decoding and evaluate the corresponding achievable rates. We then derive the optimal code diversity assuming that the feedback channel...
This paper gives the system model and the STBC encoding and decoding schemes in MIMO-OFDM system according to STBC coding theories. It focuses on researching and simulating the MIMO-OFDM system's performances, which had added STBC. We had analyzed and simulated BER performance of the system with different number of transceiver antennas. At the same time, BER performance of the system with different...
In this paper, we show how to design super-orthogonal space-time trellis codes (SOSTTCs) using the differential binary phase-shift keying (PSK) modulation for noncoherent communication systems, for which the knowledge of the channel state information (CSI) at the receiver is not necessary. Moreover, a new decoding algorithm with reduced decoding complexity is proposed. In all simulations, a geometric...
A multiple-input multiple-output (MIMO) single-carrier frequency domain equalization (SC-FDE) testbed which can emulate a practical broadband system is described. A scheme combining space-time transmit diversity with SC-FDE was implemented and evaluated on the testbed. After the hardware configuration, software algorithms incorporating the space-time block coding and decoding, synchronization, channel...
In this paper, we propose a maximum likelihood (ML)-like performance reduced computational complexity sorted orthotope sphere decoding (OSD), and zero forced (ZF) sorted OSD algorithms for the spatial multiplexing (SM) in a multiple-input multiple-output (MIMO) system. In comparison with the original OSD our technique reduces the number of partial Euclidean distance (PED) computations by up to 28%,...
Sphere decoding (SD) is an efficient algorithm which has been proposed in Multiple-input Multiple-output(MIMO) digital communications. Sphere decoding can avoids to search for the element like maximum-likelihood (ML) decoder thus reduces the decoding order of complexity effectively. However, SD also has high complexity in some situations. The complexity of the algorithm are controlled by radius and...
In this paper, we express the power consumption for the wireless receiver employing multiple antenna technique as a closed form function of the number of antennas, time duration, power dissipation for carrier sensing and data decoding, and the probability of successful carrier sensing. Based on the analytical model, we show that when MAC level power save mode is combined with PHY level power save...
A MIMO chip for 3GPP-LTE standard and beyond is described. The chip implements sphere decoding algorithm with 16-core architecture. The chip is flexible to support multiple configurations: antenna arrays from 2×2 to 8×8, modulations from BPSK to 64QAM, FFT sizes from 128 to 2048 and hard/soft outputs. The chip dissipates 5.8mW for the 3GPP-LTE standard in 3.35mm2 area in 65nm CMOS.
Coordinated multi-point processing at multiple base stations can improve coverage and throughput for future cellular systems. In this paper, we study the coordinated reception at multiple MIMO base stations by proposing cooperative multi-cell automatic repeat request (ARQ) protocols via wired backhaul links. In particular, we consider three protocols where the cooperative base stations employ different...
The QR Decomposition (QRD) of communication channel matrices is a fundamental prerequisite to several detection schemes in Multiple-Input Multiple-Output (MIMO) communication systems. Herein, the main feature of the QRD is to transform the non-causal system into a causal system, where consequently efficient detection algorithms based on the Successive Interference Cancellation (SIC) or Sphere Decoder...
To resolve today's spectrum scarcity problem, cognitive radio network is widely expected to usher in the next wave in wireless communications. This paper has developed a high-speed sphere decoder for multiple-inputs multiple-outputs (MIMO) transceivers used in cognitive radio networks. First, a novel sphere decoding algorithm is proposed which increases the decoding speed by 30% without any noticeable...
In Multi-user, Multiple-Input, Multiple-Output (MU-MIMO) wireless cellular where Quality of Service (QoS) is interference-limited, a variety of power control, precoding and decoding non-linear problems exist. Even though the sum capacity of centralized schemes (either at transmission or reception) has already been computed, the search for efficient practical schemes which can achieve this capacity...
In this paper, we consider a robust approximate lattice alignment design for K-pairs quasi-static MIMO interference channels. The traditional interference alignment on the signal space is infeasible for K > 3 and perfect channel state information (CSI) is required for all the alignment schemes in the literature, which is impractical in practice. Furthermore, the structured lattice, widely used...
The K × 2 multiple input multiple output (MIMO) X-channel with constant channel coefficients available at all transmitters and receivers is considered. A new alignment scheme, named layered interference alignment, is proposed in which both vector and real interference alignment techniques are exploited together with joint processing at receiver sides. Data streams, having fractional multiplexing gains,...
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