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作者： Roberto Petroccia Pietro Cassarà Konstantinos Pelekanakis NATO STO Centre for Maritime Research and Experimentation Viale S. Bartolomeo 400 La Spezia Italy CNR ISTI Via Giuseppe Moruzzi 1 Pisa Italy

ISBN: (纸本)9781728114521

We consider an Underwater Acoustic Network (UAN) where each node is equipped with a suite of signals and so there is the flexibility to aim for different bit rates at each transmission slot. A Cross-Entropy (CE) centralized algorithm is explored to optimize the combination of modulation scheme and transmission power level in the presence of unreliable channels. Optimization metrics such as throughput, energy per bit, latency and their combination are considered. The motivation for this research stems from the fact that surveillance networks using battery-powered Autonomous Underwater Vehicles (AUVs) need to be able to promptly deliver critical data while prolonging their lifetime and reducing the footprint of their transmissions. The proposed strategy has been validated by post-processing thousands of acoustic signals recorded during the Littoral Acoustic Communications Experiment 2017 (LACE17) sea trial in the Gulf of La Spezia, Italy. Our analysis shows the trade-off between the bit rate and the transmission power given the selected optimization metrics. The solution computed when combining all the considered metrics makes possible to improve up to three times the throughput performance and up to one order of magnitude the energy consumption with respect to considering single other optimization metrics.

关键词： Underwater acoustic communications Underwater acoustic networks Adaptive modulation and coding Cross-Entropy strategy Software-defined acoustic modem Bit rate underwater acoustic communication modulation coding power transmission energy consumption Metronidazole FIRST ORDER Acoustics Underwater Communication Research Wireless sensor networks audio signals transmission

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Interpulse-frequency-agile and intrapulse-phase-coded waveform optimisation for extend-range correlation sidelobe suppression

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IET RADAR SONAR AND NAVIGATION 2017年第10期11卷 1530-1539页

作者： Mao, Zhineng Wei, Yinsheng Harbin Inst Technol Dept Elect Engn Xidazhi St 92 Harbin Heilongjiang Peoples R China

Conventional stepped-frequency (SF) waveform utilises the frequency step between pulses to span a wide bandwidth. However, the frequency step size is limited by the width of the pulse to prevent the grating lobes, and the first lobe is about -13dB due to the uniformly sampling in frequency. Modulating the pulses [e.g. phase-coded (PC) modulation or linear frequency modulation] can increase the frequency step size and improve the performance of the sidelobes, but the sidelobes of the modulated SF waveform are still not the best. In this study, a PC frequency-hopping (PCFH) waveform to achieve optimal extend-range correlation sidelobes is presented. The presented waveform applies non-linear frequency evolution, optimal frequency order and different polyphase code to each pulse. In comparison to the SF waveform, the PCFH waveform has much higher degrees of freedom for suppressing extend-range correlation sidelobes. The authors propose a design scheme, which sequentially optimises the interpulse frequency, the FH order and the intrapulse-polyphase code to achieve the optimal extended-range correlation sidelobes. Simulation results validate the performance of the optimised waveform and the feasibility of the involved design method.

关键词： phase coding modulation coding frequency modulation correlation methods optimisation frequency hop communication interpulse-frequency-agile waveform optimisation intrapulse-phase-coded waveform optimisation extend-range correlation sidelobe suppression stepped-frequency waveform SF waveform grating lobes phase-coded modulation PC modulation linear frequency modulation PC frequency-hopping PCFH waveform nonlinear frequency evolution optimal frequency order polyphase code

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Silicon-Based Integrated Tunable Fractional Order Photonic Temporal Differentiators

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JOURNAL OF LIGHTWAVE TECHNOLOGY 2017年第12期35卷 2487-2493页

作者： Liu, Weilin Zhang, Weifeng Yao, Jianping Univ Ottawa Sch Elect Engn & Comp Sci Microwave Photon Res Lab Ottawa ON K1N 6N5 Canada

Two integrated fractional-order photonic temporal differentiators based on two Mach-Zehnder interferometer (MZI) structures implemented on a silicon-on-insulator (SOI) platform are designed, fabricated, and experimentally evaluated. The first photonic temporal differentiator employs a multimode interference (MMI) coupler as one of the two 3-dB couplers of the MZI. By changing the polarization state of the input optical signal, the coupling coefficient of the MMI is changed, which leads to the change of the phase shift in the destructive interference wavelength, and a photonic temporal differentiator with a tunable fractional order is implemented. The second photonic temporal differentiator is designed to have two cascaded MZIs, a balanced MZI, and an unbalanced MZI. A phase modulator (PM) is incorporated in one of the two arms of each of the MZIs. The balanced MZI with a PM forms an active tunable coupler, which is used to actively tune the fractional order of the temporal differentiator. The PMin the unbalanced MZI is used to tune the operating wavelength. The two photonic temporal differentiators are designed and fabricated in a CMOS compatible SOI platform, and their performance is evaluated experimentally. The experimental results show that both temporal differentiators can have a tunable fractional order from 0 to 1. In addition, the use of the active temporal differentiator to perform high-speed coding with a data rate of 16 Gb/s is experimentally evaluated.

关键词： modulation coding optical differentiator silicon-on-insulator silicon photonics

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Analog Network-Coded modulation With Maximum Euclidean Distance: Mapping Criterion and Constellation Design

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IEEE ACCESS 2017年 5卷 18271-18286页

作者： Yu, Zhijiang Chen, Wei Guo, Xin Chen, Xiang Sun, Chen Tsinghua Univ Dept Elect Engn Beijing 100084 Peoples R China Tsinghua Univ Tsinghua Natl Lab Informat Sci & Technol Beijing 100084 Peoples R China Sony China Ltd Sony China Res Lab Beijing 100028 Peoples R China

Physical-layer network coding holds the great potential of improving the power efficiency and the spectral efficiency for the two-stage transmission scheme. The first stage is the multiple access stage, where two source nodes (SN1 and SN2) simultaneously transmit to the relay node (RN). The second stage is the Broadcast stage, where the RN broadcasts to the two destination nodes (DN1 and DN2), after a denoising-and-mapping operation. In this paper, we investigate the joint network-coded modulation design of the two stages. A universal modulation framework is built, referred to as analog network-coded modulation strategy, which is more general than the former modulation design mechanism. More explicitly, we propose a joint design criterion to guarantee the forwarding reliability at the RN. The criterion ensures that the neighboring constellation points superposed at the RN are mapped to an identical constellation point for broadcasting if their Euclidean distance (ED) is less than a given threshold. This yields a non-convex polynomial optimization problem by minimizing the average transmission power and constraining the ED among the constellation points. By solving the problem, we propose two joint modulation design algorithms, termed as the Enhanced Semidefinite Relaxation Algorithm and the Fast-Relaxation Algorithm, respectively. The two algorithms can achieve the tradeoff between the communication performance and the computation resources. As for the Fast-Relaxation Algorithm, the theoretical performance boundary is derived in detail. Simulation results demonstrate the effectiveness of both the proposed algorithms by comparing symbol error rate performance with the existing modulation design methods.

关键词： Two-way relaying network coding modulation coding physical layer constellation design optimization methods relaxation methods semidefinite programming Gaussian randomization

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Coded transceive spatial modulation with block Markov superposition transmission

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ELECTRONICS LETTERS 2017年第10期53卷 657-658页

作者： Wang, Leijun Ma, Xiao Sun Yat Sen Univ Sch Elect & Informat Technol Guangzhou 510006 Guangdong Peoples R China Sun Yat Sen Univ Sch Data & Comp Sci Guangzhou 510006 Guangdong Peoples R China Sun Yat Sen Univ Guangdong Key Lab Informat Secur Technol Guangzhou 510006 Guangdong Peoples R China

A new multiple-input multiple-output system, referred to as transceive spatial modulation (TRSM), which integrates transmit spatial modulation (SM) and receive SM. In the TRSM system, information bits are carried by the conventional amplitude-phase modulation as well as by the indices of both the transmit and the receive antennas. To improve the bit-error-rate performance, block Markov superposition transmission (BMST) is applied to the TRSM, resulting in BMST-TRSM, where BMST is a recently proposed coding scheme and can be easily designed according to the spectral efficiency requirement. To reduce the computational complexity, a layered (suboptimal) soft detection algorithm is presented, which delivers a list of candidate spatial points (antenna combinations) first. Numerical results show that the proposed TRSM system performs well over the Rayleigh fading channels.

关键词： amplitude modulation antenna arrays block codes communication complexity error statistics Markov processes MIMO communication modulation coding phase modulation radio transceivers Rayleigh channels receiving antennas transmitting antennas

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modulation Classification Based on Extensible Neural Networks

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MATHEMATICAL PROBLEMS IN ENGINEERING 2017年第1期2017卷 1-10页

作者： Yang, Guan Qing Shenyang Aerospace Univ Coll Elect & Informat Engn Shenyang 110136 Liaoning Peoples R China

A deep learning architecture based on Extensible Neural Networks is proposed for modulation classification in multipath fading channel. Expanded Neural Networks (ENN) are established based on energy natural logarithm model. The model is set up using hidden layers. modulation classification based on ENN is implemented through the amplitude, phase, and frequency hidden network, respectively. In order to improve Probability of Correct classification (PCC), one or more communication signal features are extracted using hidden networks. Through theoretical proof, ENN learning network is demonstrated to be effective in improving PCC using amplitude, phase, and the frequency weight sub network, respectively. Compared with the traditional algorithms, the simulation results show that the proposed ENN has higher PCC than traditional algorithm for modulation classification within the same training sequence and Signal to Noise Ratio (SNR).

关键词： modulation coding NEURAL networks (Computer science) LOGARITHMS SIGNAL-to-noise ratio RADIO transmitter fading

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Symbol error rate of QO-STBC based decode-and-forward cooperative communication system over generalised η-μ and κ-μ fading channels

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IET COMMUNICATIONS 2017年第9期11卷 1379-1386页

作者： Surendar, Maruthu Rajput, Sourabh Singh Muthuchidambaranathan, P. Natl Inst Technol Dept Elect & Commun Engn Tiruchirappalli 620015 Tamil Nadu India

In this study, the authors derive the closed form expressions for symbol error rate (SER) of a quasi-orthogonal space-time block code (QO-STBC) based multi-relay cooperative communication system using M-ary phase-shift keying (M-PSK) modulation over generalised kappa-mu fading channel. For the same system over eta-mu fading channel, due to the unobtainability of the closed form SER expressions, the analysis is restricted to binary-PSK and the bit error rate (BER) has been derived. The authors employ decode-and-forward protocol at the relays and maximal ratio combiner at the destination. For the ease of analysis, the authors consider a three relay cooperative network and the SER has been derived which could be extended to any number of relays or QO-STBCs. First, the expressions of SER were expressed in terms of moment generating function (MGF) and finally, the available closed form expression for MGF of eta-mu and kappa-mu channel distributions are used to obtain the final expression of theoretical BER/SER. The validity of the obtained BER/SER expressions for a three relay cooperative system are verified through Monte-Carlo simulations by varying the channel parameters of eta-mu and kappa-mu fading channels.

关键词： fading channels decode and forward communication cooperative communication error statistics phase shift keying relay networks (telecommunication) diversity reception Monte Carlo methods space-time block codes channel coding modulation coding QO-STBC-based decode-and-forward cooperative communication system quasi-orthogonal space-time block code multirelay cooperative communication system M-ary phase-shift keying modulation M-PSK modulation symbol error rate SER BER generalised - fading channel distribution generalised - fading channel distribution bit error rate maximal ratio combiner decode-and-forward protocol relay cooperative network moment generating function MGF Monte-Carlo simulation

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9/12 2-D modulation Code for Bit-Patterned Media Recording

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IEEE TRANSACTIONS ON MAGNETICS 2017年第3期53卷 ar-ar页

作者： Chi Dinh Nguyen Lee, Jaejin Soongsil Univ Sch Elect Engn Seoul 06987 South Korea

This paper presents a 9/12 2-D modulation code to overcome 2-D interference effects in bit-patterned media recording (BPMR) systems. Next-generation storage systems that are challenged by the superparamagnetic effect require new technologies to be developed, and for magnetic recording, BPMR technology is regarded to be one of the most promising candidates to extend area density beyond 1 Tb/in(2). BPMR systems not only help to reduce transition noise and non-linear bit shift, but they also simplify the tracking operation. Nevertheless, some challenges arise for BPMR systems from a signal processing point of view. One of the primary challenges in the systems is the 2-D interference due to the effects of both the along- and across-track intersymbol interference. Moreover, the effect of media noise and the physical limits of the electromechanical components also negatively impact the system performance. The proposed modulation code converts 9 b sequences of user data into 2-D output codewords in 6-by-2 arrays to avoid fatal interference as much as possible, and a reasonable Hamming distance is also ensured for the codeword set. The proposed code achieves gains of about 2 and 1 dB over a system without encoding and a system with 6/8 modulation coding at the same code rate, respectively. Moreover, the performance of the 9/12 2-D modulation codes according to the different array sizes is also investigated.

关键词： Bit-patterned media recording (BPMR) intersymbol interference (ISI) intertrack interference (ITI) modulation coding

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On the Achievable Rate of Bistatic Modulated Rescatter Systems

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IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY 2017年第10期66卷 9609-9613页

作者： Duan, Ruifeng Jantti, Riku Yigitler, Huseyin Ruttik, Kalle Aalto Univ Dept Commun & Networking Espoo 02150 Finland

In ambient rescatter communications, devices convey information by modulating and rescattering the radio frequency signals impinging on their antennas. In this correspondence, we consider a system consisting of a legacy modulated continuous carrier multiple-input-multiple-output link and a multiantenna modulated rescatter (MRS) node, where the MRS node modulates and rescatters the signal generated by the legacy transmitter. The receiver seeks to decode both the original message and the information added by the MRS. We show that the achievable sum rate of this system exceeds that which the legacy system could achieve alone. We further consider the impact of channel estimation errors under the least squares channel estimation and study the achievable rate of the legacy and MRS systems, where a linear minimum mean square error receiver with successive interference cancellation is utilized for joint decoding.

关键词： Backscatter bistatic channel rescatter keyhole channel MIMO modulation coding polyphase coding

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Constrained Turbo Product and Block-Convolutional Codes in Wireless Applications

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IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY 2017年第5期66卷 4491-4495页

作者： Hu, Yuan Fonseka, John P. Bo, Yu Dowling, Eric M. Torlak, Murat Univ Texas Dallas Dept Elect Engn Richardson TX 75080 USA Trellis Phase Commun LP Plano TX 75670 USA

Constrained interleavers are used in constrained turbo product codes (CTPCs) and constrained turbo block-convolutional (CTBC) codes. The constrained interleaver delivers an interleaver gain close to uniform interleaving while also increasing the minimum Hamming distance. In this study, new and improved single row(SR) versions of the previous codes, called SR-CTPCs and SR-CTBC codes, are introduced that have higher interleaver gain, better performance, and much more flexible frame sizes as needed in wireless applications. Compared with the WiMax and the long-term evolution standards, it is demonstrated that SR-CTPC and SR-CTBC codes perform better than those currently used in the wireless standards.

关键词： Concatenated coding modulation coding

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