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We propose a simple yet effective wireless network coding (NC) and decoding technique. It utilizes spatial diversity through cooperation between nodes which carry out distributed encoding operations dictated by generator matrices of linear block codes. For this purpose, we make use of greedy codes over the binary field and show that desired diversity orders can be flexibly assigned to nodes in a multiple...
In this paper we deal with the problem of minimizing the complexity of an IR-UWB system by the introduction of Time-Reversal, under a power constraint and fixing a reachable performance in terms of BER. An approximate trade-off in the choice of the number of taps at the transmitter and the number of fingers at the receiver is proposed.
The robustness of the time reversal (TR) scheme in a non stationary channel environment has been previously studied for ultra-wide band (UWB) channels. However, its robustness with different bandwidth specially for bandwidths significantly lower than ultra-wide bandwidths has not been established. In this paper, the performance of a TR communication system has been studied for large number of bandwidths...
Intra-vehicular wireless sensor networks is a promising new research area that can provide part cost, assembly, maintenance savings and fuel efficiency through the elimination of the wires, and enable new sensor technologies to be integrated into vehicles, which would otherwise be impossible using wired means, such as Intelligent Tire. The most suitable technology that can meet high reliability, strict...
In sub-band ultra-wideband (SUWB) systems, the use of spreading codes in conjunction with sub-banding enables energy efficient reduced sampling rate receiver designs. In this work, the orthogonal frequency division multiplexing (OFDM) technique is proposed for SUWB systems as a means to mitigate the multipath fading effects of the channel. The OFDM demodulation performed at the sub-sampled rate with...
We study the outage performance of an amplify-and-forward (AF) cooperation with full duplex relaying (FDR). When there exists a non-negligible direct link or residual self interference (RSI), full duplex relaying turns the effective channel into a frequency selective channel. Assuming minimum mean squared error decision feedback equalization (MMSE-DFE) at the destination, we derive tight closed-form...
In this paper, we investigate different HARQ strategies with unreliable feedback channel. In classical approaches, retransmitted packets are different versions of the same user data. In order to improve HARQ performance, we propose to construct redundancy packets by jointly encoding several data packets. This strategy is referred to as HARQ Multiple Packet Incremental Redundancy (MP-IR). It can eliminate...
This paper presents two new techniques employing bandwidth-efficient modulation to enable two partners to cooperatively convey their data to a common destination. Both approaches integrate relaying and channel coding, exploiting the fact that each partner knows the data relayed by the other partner to enhance the partner-to-partner link. The first approach is based on bit-interleaved coded modulation...
In this paper, we develop a novel joint transmit and receive design for multiuser MIMO (MU-MIMO) systems. The proposed scheme exploits the channel temporal correlation and incorporates the matched filter (MF) combining vector into the beamforming design. Considering the beamforming is optimized with the outdated channel state information (CSI) feedback, we design the beamformer by maximizing the conditional...
Bit and power loading schemes for a single-user multiple-input multiple-output channel using a minimum mean-square error receiver are proposed. Such schemes are derived without the benefit of instantaneous channel state information (CSI) at the transmitter, on the basis of only statistical CSI. They exploit the relationships between the average bit error probability at the receiver and the power allocation...
In this paper, three novel efficient power control algorithms are proposed for V-BLAST system with both total power constraint (TPC) and per-antenna power constraints (PAPC). Through analysis of the Karush-Kuhn-Tucker (KKT) conditions of the optimization problem, we find out that the antennas with the optimal power control can be divided into two sets. The optimal allocated power (OAP) of each antenna...
A new space-time block code (STBC) is presented for distributed 4 × 2 multiple-input multiple-output (MIMO) systems. A 2 × 2 full-rate full-diversity (FR-FD) low complexity space-time code, presented by Sezginer and Sari, is employed for two distributed links. Alamouti STBC is applied over the two links to obtain a double layer space-time block code (DLSTBC) providing full diversity in a distributed...
We propose a packet delayed lattice reduction aided MIMO detection for 802.1 1n system. Lattice reduction algorithms are iterative in nature that results in long latency. In high throughput systems like 802.11n, reduction of latency via parallelization causes high hardware complexity. Without parallelization, the receiver needs to buffer the incoming data until the lattice reduction finishes. Depending...
In this paper, we propose an orthogonal space-time block coding (STBC) for continuous phase modulation (CPM) over frequency-selective channels. The new method maintains the constant envelope and the phase continuity of the CPM waveforms by inserting three blocks of data-dependent symbols in addition to a cyclic prefix (CP). At the transmitter, the data blocks are precoded and transmitted in two antennas...
We consider rate splitting and interference cancelation in Device-to-Device (D2D) communications underlaying a cellular network. We assume that a transmitted message is split into a private and a public part, as in Han-Kobayashi scheme. The private part is decodable only by the intended receiver, whereas the public part is in addition decodable by an interference victim. The receivers run a best-effort...
In this paper, we investigate the performance of relay selection in an underlay cognitive radio system in the presence of primary user (PU) interference. In particular, we consider a secondary multi-relay network operating in the amplify-and-forward (AF) mode and only the “best” relay which satisfies an index of merit is selected. The proposed selection strategy takes into consideration the effect...
In order to maximize the spectral efficiency, the current wireless systems tend to allocate the same frequency resources to different users, which causes the so-called Co-Channel Interference (CCI) on the signal received by the mobile user. If not handled appropriately, CCI may seriously degrade the communication performance. Therefore, for more reliable performance, robust transceiver techniques...
We investigate simplified, yet mismatched, receivers for SC-FDMA MIMO transmission currently employed in the 3GPP LTE-Advanced uplink. The receivers are based on frequency domain equalization and time domain detection. Rates achievable by those mismatched receivers with arbitrary input alphabets are derived in terms of generalized mutual information. The results allow to compare the impact of certain...
In the next generation cellular systems, such as LTE-A (Release 10 and beyond), relay node (RN) deployment has been adopted due to its potentials in enlarging coverage and increasing system throughput, even with primitive relaying functionalities. For example, in LTE-A Release 10 only Type-I (non-transparent) RNs are considered wherein no cooperative transmission to the Donor evolved-NodeBs (DeNBs)...
Deliberate clipping is a simple solution to high Peak-to-Average Power Ratio problem of OFDM signal. In Amplify-and-Forward OFDM relay networks, due to the limited resource, deliberate clipping is also suggested. However, clipping is a nonlinear process and may cause significant performance degradation. Based on Bussgang Linearization Theory, we provide a linear system model for Amplify-and-Forward...
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