Power management for embedded devices in Fifth Generation (5G) networks is mandatory synchronizing the communication between devices. In such cases, need integration power optimization recommended aiding lossless and high-speed communications. To suppress issues hardware-based failures during transmissions, this article proposes a Compressive Transmission Scheme (CTS) through Regulation (PR). The proposed scheme identifies multiple transmission possibilities under low high throughput...

System virtualization, which provides good isolation, is now widely used in server consolidation. Meanwhile, one of the hot topics this field to extend virtualization for embedded systems. However, current popular platforms do not support real-time operating systems such as Linux well because platform ware, will bring low-performance I/O and high scheduling latency. The goal paper optimize Xen be system friendly. We improve two aspects platform. First, we xen scheduler manage latency...

The vector approximate message passing (VAMP) soft frequency-domain equalizer (SFDE) has been proposed for turbo equalization. It consists of an inner (ISE) and slicer (ISS), which iteratively exchange block-wise extrinsic information to improve the equalization performance, analogous outer iteration between a decoder. However, comparison VAMP-SFDE with other types self-iterative SFDEs, including interference cancellation (SI-BSIC) SFDE generalized (GAMP) SFDE, is lacking. Moreover,...

It is crucial to minimize virtualization overhead for virtual machine deployment. The conventional ×86 CPU incapable of classical trap-and-emulate virtualization, leading that paravirtualization was the optimal strategy formerly. Since architectural extensions are introduced support hardware assisted becomes a competitive alternative method. Hardware superior in and memory yet still valuable some aspects as it capable shortening disposal path I/O virtualization. Thus we propose hybrid which...

Nowadays, the vulnerability of cloud environment exposed in security places Virtual Machine Introspection(VMI) at risk: once attackers subvert any layers environment, such as host, virtual machine manager(VMM) or qemu, VMI will be undoubtedly to those too. Nearly all existing techniques implicitly assume that both VMM by which accesses specific VM data and host is running on, are nonmalicious immutable. Unfortunately, this assumption can potentially violated with growing shortage...

Vertical underwater acoustic (UWA) communications play a crucial role in deep-sea applications. A vertical UWA channel generally features moderate multipath but with time-varying Doppler shifts as well loud impulsive noise. To achieve robust single-carrier communication, this paper proposes an enhanced iterative receiver. First, spline interpolation-based timing estimation approach is proposed to compensate for the effects efficiently. Then, residual errors and interference are tackled by...

In this article, two ultrashort baseline (USBL) location methods for underwater broadband signal are proposed. order to improve the positioning accuracy of acoustic positioning, coarse time delay is measured by parabolic interpolation cross correlation results. According delay, ambiguity number phase at peak solved and twice, so as obtain high-precision difference accuracy. This method suitable case without near body multipath. Aiming multipath problem, its influence on resolution analyzed....

Underwater acoustic channels are characterized by a time-varying multipath structure with long delay spread. The is usually very sparse. Direct-adaptation based turbo equalizer low-complexity and effective method to combat the inter-symbol interference caused multipath. This paper studies determinations of tap positions linear equalizers in direct-adaptation multichannel equalizer. A multiple threshold retraining scheme proposed determine sparse position direct-adaptive equalization. length...

In this report, signal processing in underwater acoustic communication system for manned deep submersible “Jiaolong” is introduced. 1. Four methods are integrated to meet different needs: (1) coherent communication, with a variable transmission rate from 5kbps 15kbps, transmit images. (2) Non-coherent 300bps, texts, instructions, and sensor data. (3) Spread spectrum 16bps, instructions. (4) Underwater voice using analogy modulation method human voice. 2. Signal mainly consists of...

多通道判决反馈均衡器(MC-DFE)是水声相干通信克服信道多径效应、消除码间干扰(ISI)的主要手段。为了减少多通道数据处理的复杂性、优化算法、提高算法精度，该文提出了自适应自最优预合并多通道判决反馈均衡算法。该算法将快速自优化LMS分集合并(FOLMSDC)算法、快速自优化LMS(FOLMS)算法和快速自优化LMS相位补偿(FOLMSPC)算法有机地结合在一起，使用统一的误差信号，按照最小化均方误差(MMSE)准则调节各部分的系数，从而实现均衡器性能的全局最优。仿真试验和湖上试验对该算法的性能进行了分析。实验结果表明，该文提出的算法可以进一步减少运算量，提高通信系统的接收性能，算法性能优于已有算法。

The Shipborne acoustic communication system of the submersible Shenhai Yongshi works in vertical, horizontal and slant channels according to relative positions. For ease use, an array combined by a vertical-cone directional transducer horizontal-toroid one is installed on mothership. Improved techniques are proposed combat adverse channel conditions, such as frequency selectivity, non-stationary ship noise, Doppler effects platform's nonlinear movement. coherent modulation, turbo-coded...

In underwater acoustic communication networks, most of the energy used by modem is consumed in waiting for data reception. We designed an on-duty circuit to reduce power consumption when network idle. The uses a separate low-voltage supply. To control circuit, status divided into three operating modes: sleep mode, monitor mode and working mode. When idle, turns or which reduces consumption. By calculation experimental verification, it verified that four D-size lithium batteries can support 3...

In the cableless seafloor observation networks (SONs), links among network nodes rely on underwater acoustic communication (UAC). Due to energy constraint and high-reliability requirement of SONs, noncoherent UAC has been a preferred choice, even though scheme generally suffers from low spectral efficiency. this paper, we propose high-spectral-efficiency transmission which is implemented as an orthogonal frequency-division multiplexing (OFDM) system adopting on-off keying (OOK) modulation....

Once compromising the hypervisor, remote or local adversaries can easily access other customers' sensitive data in memory and context of guest virtual machines (VMs). VM isolation is an efficient mechanism for protecting VMs from unauthorized access. However, previous systems either modify hardware architecture introduce a software module without being protected, most them focus on x86 architecture.

Concatenated code based on nonbinary LDPC and Hadamard is used for noncoherent underwater acoustic communication system. 32-ary (620, 320) regular irregular constructed by quasi-cyclic extension method Progressive edge-growth (PEG) algorithm, respectively. Under non-Gaussian noise model, Gaussian mixture model (GMM) to fit the noise, parameters in GMM estimated Expectation Maximization (EM) probability density of further estimated. In Rayleigh fading channel, posterior probabilities...

In recent years, whether autonomous monitoring of ocean environment, deep seabed resources surveying, underwater sensor networks, or military detection etc, there are widespread needs acoustic networks (UANs). This paper provides a brief overview the characteristics and advances UANs, main research contents key technologies UANs analyzed, including physical layer technologies, media access control (MAC) protocols routing protocols. Underwater communication (UWAC) in is basis for its covers...

A source number estimation using eigenspace is presented. It projects estimated covariance matrix of array signal into eigen subspace and noise respectively. Using the orthogonality between subspace, it easy to differentiate contribution by criterion value, which magnitude projection. Like direction arrival (DOA) estimate algorithm, uses eigenvalue decomposition with MtimesM order (M elements). Hence much computational burden can be saved. To reduce more burden, realized in real-valued...

Numerous operating systems have been designed to manage and control system resources with large complicated features, so they need high security protection. However, previous applications can not provide adequate protection due the untrusted execution environment. Furthermore, these strategies cannot support a universal cross-platform requirements. This paper presents VASP, hypervisor based monitor which allows trusted environment various malicious behaviors in system. is achieved by taking...

A probabilistic constellation shaping (PCS)-aided single-carrier transceiver is proposed to improve spectral efficiency for underwater acoustic (UWA) communications. At the transmitter, information bits are input into a distribution matcher followed by systematic binary encoder, which yields sequence of sign with uniform and amplitude non-uniform distribution. Based on these two sequences, PCS then realized mapping coded onto quadrature modulation constellation. receiver, an improved...

Underwater wireless sensor networks (UWSNs) are significantly different from terrestrial in the following aspects: low bandwidth, high latency, variable topology, limited battery, processing power and so on. These new features pose many challenges to design of self-organizing routing protocol for UWSNs. This paper focuses on application Ad Hoc On-demand Distance Vector (AODV) In order solve problems packet collision excessive energy consumption associated with flooding-based discovery method...

The underwater acoustic communication system (UACS) is an important part of AUV. We developed for a AUV: IASS-1, which based on both MFSK and MPSK. Generally AUV sends large amount data to the host vessel, MPSK modulation adopted. receiver vessel adopts space diversity (SD), decision feedback equalizer (DFE), fast self-optimized LMS phase estimator (FOLMSPE) techniques jointly. (FOLMS) algorithm implemented in DFE. A short vertical hydrophone array suspended or towed signal reception....