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802.11 Wireless Local Area Network (WLAN) technology is now common in power sensitive devices like smart phones and personal digital assistants (PDAs). In this article, we present an accurate power consumption model based on the Bianchi model [13] and the power measurement in PHY layer [9] to predict the power consumption of 802.11n and Multiple-Inputs-Multiple-Outputs (MIMO) mode of 802.11n. In this...
Interference coordination methods for Evolved-Multimedia Broadcast/Multicast Service (E-MBMS) in Long Term Evolution Advanced (LTE-A) are presented. In this paper, OFDM/OFDMA signals based on LTE parameters are combined with MIMO, Turbo codes and signal space diversity methods. Different interference coordination techniques, such as, MIMO coordination, Fixed Relay stations and adaptive frequency reuse...
We consider a two-user Gaussian multiple-input multiple-output (MIMO) broadcast channel with a common multiple-antenna relay, and a shared digital (noiseless) link between the relay and the two destinations. For this channel, this paper introduces an asymptotically sum-capacity-achieving quantize-and-forward (QF) relay strategy. Our technique to design an asymptotically optimal relay quantizer is...
Combining coding, modulation, transmit and receive diversity, and validly increases the anti-noise performance in fading channels, OSTBC (orthogonal space-time block codes) is a new channel coding technology accompanying with the extensive application of wireless communication. Based on typical channel model of the OSTBC in MIMO (multiple-in, multiple-out) wireless communication channels, a general...
In this paper, we study the strategy of Demodulation-and-Forward(DmF) based on joint network and channel coding and extend it to multi-user access relay channel . In DmF model, there are two users accessing the relay. Users encode original signals using LDPC codes. In the relay, we conduct demodulation instead of decoding and implement network coding that is the Demodulation-and-Forward(DmF) method...
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...
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...
We address the problem of a multi-user relay network, where multiple single-antenna node pairs want to exchange information by using a multiple antenna relay node. Due to the half-duplex constraint of the relay, the exchange of information takes place in two steps. In the first step, the nodes transmit their data to the relay, while in the second step, the relay is broadcasting the data by using linear...
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 study the degraded multi-receiver wiretap channel with public and confidential messages. In this channel, there is a transmitter that wishes to communicate with two legitimate users in the presence of an external eavesdropper. The legitimate users and the eavesdropper satisfy a certain degradation order. In this paper, we study this channel model for the scenario where the transmitter sends a pair...
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...
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...
In this paper, we proposed a system that combines AMC and MIMO schemes. While conventional AMC system changes only the coding rate and modulation, the proposed AdaptiveMCM system also selects the MIMO scheme (diversity, multiplexing) according to channel condition. Furthermore, by applying pre-coding and antenna subset-selection we not only produce optimal performance but also increase the data rate...
In this paper, we extend the non-vanishing determinant (NVD) criterion to the selective fading channel case. A new family of split NVD parallel codes, that satisfies this design criterion, is proposed to achieve the optimal diversity multiplexing tradeoff (DMT) derived by Coronel and Bölcskei, IEEE ISIT, 2007. This result is of significant interest not only in its own right, but also because it settles...
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...
Precoding is an efficient approach to obtain high channel capacities and high quality in multiple-input-multiple-output systems and draws much attention in recent researches. In the codebook-based precoding systems, the tradeoff between performance and feedback overhead should be considered. In this paper, a novel version of the Linde-Buzo-Gray (LBG) algorithm is first utilized in the codebook design...
This paper deals with the network spectral efficiency/capacity analysis of multiple-input multiple-output (MIMO) ad hoc network with k simultaneous communicating transceiver pairs in two scenarios; quantized beamforming for achieving finite rate feedback and imperfect channel state information at the transmitter (CSIT). In the quantized beamforming, each receiver chooses the best beamforming vector...
In this paper, we investigate a cross-layer framework in multiuser diversity system. Rate compatible Low-density Parity-check codes (LDPC) and space-time block codes (STBC) are employed. Under the assumption that the channel state information (CSI) is known at the receiver and the adaptive control signaling can be perfectly fed back to the transmitter, we first derive the expressions for the throughput...
This paper analyses ambiguity suppression caused by multiple-input multiple-output (MIMO) SAR azimuth nonuniform samplings. Two methods are analyzed: azimuth spectrum reconstruction algorithm and minimum mean square error (MMSE) imaging algorithm. The azimuth spectrum reconstruction algorithm can reconstruct the scene fine resolution, while the nonideal orthogonality of multi-channel encoding waveforms...
MIMO applications that involve handheld devices such as cell phones pocket PCs or PDAs require antennas to be closely spaced, which result in mutual coupling among antennas and high spatial correlation for signals. In this paper, we investigate the use of dirty paper coding (DPC), an information theoretic analysis in order to compensate for the performance degradation due to correlation and coupling...
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