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Cooperative relay has been an interesting research area for the past years as it promotes higher data rates and robust to wireless environment. IEEE Work Group initiated the use of relay stations in the IEEE 802.16e standard and it is called IEEE 802.16j. This paper proposed a multi-hop cooperative relay system with space-time codes (STC), with the integration of relay selection. In changing environment,...
The use of low-density parity-check (LDPC) codes over the multi-input multi-output (MIMO) channels has shown the performance to be achieved to the capacity limit. For the 2 × 2 MIMO system, the Golden codes were recently developed as the optimal space-time codes with a full rate and a full diversity gain. In this paper, we give the detailed system design for the concatenated coding scheme, which consists...
In highly spatially correlated channels the diversity gain achieved by space-frequency (SF) coding is significantly low. Nevertheless, when full or partial channel state information is available at the transmitter, improved performance can be obtained by combining transmit beamforming with SF coding. In this paper we propose two novel transmit beamforming techniques based on the minimum pair-wise...
Uplink collaborative multiple-input-multiple-output (MIMO) processing among multiple base stations (BSs), also known as uplink multi-BS MIMO, is an effective way to solve the inter-cell interference in cellular systems. However, the significantly increased overhead on the backhaul network due to inter-BS information exchange has seriously restricted its application in practical systems with limited...
Mobile broadcasting MIMO systems differ in several essential ways from conventional MIMO applications, especially when they are operating in single-frequency networks. There are certain channel features, like the imbalance of received average powers, which should be taken into account in system design. In this paper, space-time coding that allows reduced complexity maximum likelihood decoding of the...
The rate balancing problem is considered in the multiple-input single-output (MIMO) broadcast channel with linear transceivers. After introducing relative per-stream rate targets as auxiliary variables, the optimization is performed by a gradient projection algorithm. In addition, the transmit and receive filters are updated and the mean square error matrices are diagonalized in each iteration. Although...
Recent works on multi-user transmission techniques have shown that the linear growth of capacity in single user MIMO system can be translated to the multi-user MIMO scenario as well. In this paper, we propose a method pursuing performance gain of vector perturbation in multi-user downlink channels. Instead of exploiting the maximum available mobile users for communication, we employ small part of...
We consider a multiuser multiple-input multiple output (MIMO) Gaussian broadcast channel (BC). Assuming a sum-power constraint over all transmit antennas, the sum capacity of such a system can be achieved with dirty paper coding (DPC) which has been found as a very promising strategy. Rather than the usual sum-power constraint, in this paper we focus on the downlink of a cooperative multicellular...
In Multi-user MIMO (MU-MIMO), the Base Station (BS) schedules multiple users simultaneously on the same resources. Closed loop MU-MIMO uses explicit feedback from each of these users for scheduling and allocation of resources. In this scheme, an estimate of the SINR experienced is fed back by each user and is known as the CQI (Channel Quality Information). This CQI is used by the BS for link adaptation...
In this paper, we study various cooperative relaying transmission schemes of multiple amplify-and-forward (AF) relays system for various geometric environments in view of capacity. We consider joint encoding (JE) with channel matched filtering (CMF) and selective transmission (ST) as coordinated AF relay transmission schemes. Through relay channel model considering link SNRs, we find suitable cooperative...
Multi-user MIMO has been recently proposed as a required technology for next generation 802.11 WLAN systems. This new system which will be called 802.11ac, will provide at least 1Gbps of multi-station throughput and at least 500Mbps of single station throughput. While linear precoding can be readily used to achieve this with little complexity, we explore the possibility of employing the non-linear...
In this paper, we propose a HDTV transmission over IEEE802.3ac 4 × 5 MIMO WLAN System. The proposed system employs the next generation wireless LAN system based on IEEE802.3ac specification. It reaches more than 33 meter propagation distance by using 80 MHz of bandwidth on the 5 GHz band. In this system, video data is compressed by JPEG 2000 with error resilience tools. These tools improve error performance...
Fast Maximum Likelihood Decodable Space-Time Block Codes (STBCs) have recently gained a lot of interest for use in wireless communication systems. Several strategies have been introduced in the literature to build such codes, among them we mention the conditional detection strategy, where the code matrix can be expressed as the sum of two Orthogonal STBCs by means of a unitary matrix. Thus, the decoder...
In this paper, the performance limit of lattice sequential decoder for coded M× N MIMO channel is analysed. We determine the rates achievable by lattice coding and sequential decoding applied to such channel. The diversity-multiplexing trade- off under lattice sequential decoding is derived as a function of its parameter---the bias term. Such parameter is critical for controlling the amount of computations...
STBC-MIMO network coding with adaptive spatial modulation for the asymmetric channel and traffic is proposed in this paper. The proposed scheme can select the suitable modulation level every wireless link. In this paper, the throughput performance on the asymmetric channel of the proposed scheme are evaluated by computer simulation. As a result, it is shown that proposed the scheme is effective to...
Random Network Coding (RNC) has emerged as an important technology in wireless communication. The present paper proposes a novel cooperative Virtual-MIMO (V-MIMO) structure by applying RNC to the cooperative transmission. Then the diversity gain of the RNC-based cooperative strategy is analyzed and compared with the conventional cooperative strategies. Higher diversity gain or multiplexing gain can...
Spatial Modulation (SM) is a recently proposed joint coding and modulation scheme for Multiple-Input-Multiple-Output (MIMO) wireless systems, which is receiving a growing interest. SM offers a low-complexity alternative to the design of MIMO wireless systems, which avoids multiple Radio Frequency (RF) chains at the transmitter and high-complexity interference cancellation algorithms at the receiver,...
We obtain the degrees of freedom region of the Gaussian multiple-input multiple-output (MIMO) broadcast channel with common and private messages. We first show that a parallel Gaussian broadcast channel with unmatched sub-channels can be constructed from any given Gaussian MIMO broadcast channel by using the generalized singular value decomposition (GSVD) and a relaxation on the power constraint for...
In the IEEE 802.16d Orthogonal Frequency Division Multiplexing (OFDM) physical layer protocol, which provides the Space-Time Coding (STC) scheme to improve system performance, it is possible to get a better performance in resisting multipath fading and increasing bandwidth efficiency. However, in projects, using Multiple-Input Multiple-Output (MIMO) multiple-antenna technology is usually inconvenient...
A cooperative virtual-MIMO system that implements bit-interleaved coded modulation (BICM) transmission and compress-and-forward (CF) cooperation is presented in this paper. The key tasks of the relay include constructing a good codebook, and forwarding a compressed version of the received signals to the destination. Codebook designs of the Voronoi vector quantization (VQ) and the tree-structure vector...
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