The low-rank property of the channel covariances can be adopted to reduce overhead training in massive MIMO systems. In this paper, with help virtual representation, we apply such both time-division duplex and frequency-division systems, where time-varying scenarios are considered. First, formulate dynamic as one sparse signal model. Then, an expectation maximization-based Bayesian learning framework is developed learn model parameters channel. Specifically, Kalman filter (KF)...

As a revolutionary wireless transmission strategy, interference alignment (IA) can improve the capacity of cell-edge users. However, acquisition global channel state information for IA leads to unacceptable overhead in massive MIMO systems. To tackle this problem, paper, we propose an and soft-space-reuse (IA-SSR)-based cooperative scheme under two-stage precoding framework. Specifically, cell-center users are separately treated fully exploit spatial degrees freedoms. Then, optimal power...

As the typical delay tolerant networks, satellite networks possess intermittent connections, large-scale time delays and time-varying topologies. Obviously, such features seriously affect delivery of mission data with certain requirements on traffic or latency. To decrease time, existing relay-based contact graph routing (CGR) method selects earliest reachable path to forward data. However, this cannot guarantee transmission a large amount wastes rare opportunities. Therefore, in paper, we...

In this paper, we propose an architecture of software-defined information-centric network virtualization with device-to-device (D2D) communications, which facilitates dynamic virtual resource allocation and content caching via a networking (SDN) controller global view the system. our proposed framework, substrate physical resources can be virtualized shared among multiple mobile operators (MVNOs). Meanwhile, by means integrating D2D communications into wireless networks, is enabled not only...

In this letter, we propose a transceiver resource allocation scheme based on the time-expanded graph (TEG) for satellite networks. Due to time-varying topology of networks, design efficient requires multiple nodes make joint decision across time. To overcome problem, distribution resources is first depicted by TEG. Then, add some virtual and edges in TEG represent resources, obtain modified TEG, which can transform nodes' into link constraints. Finally, will be implemented through solving...

The calculation method, fitting function and spectrum of power spectral density (PSD) track irregularity were proposed in the paper. To improve accuracy PSD irregularity, a linear interpolation method wavelet analysis are given used to eliminate outliers trends irregularities. paper describes window function, length estimation calculate PSD. For comparison densities (PSDs) calculated with different functions, lengths methods. Combing above mentioned results data from high speed comprehensive...

Vehicular ad hoc network (VANET) is able to facilitate data exchange among vehicles and provides diverse services. Intuitively, end-to-end backlog delay bounds are considered significant metrics evaluate the quality of service in VANETs. In order analyze how multi-hop transmission impacts performance, we model process into a virtualized single min-plus convolution form. To obtain bound, consider stochastic traffic characteristics highly dynamic channel environment under static priority,...

The surface stockpiling of phosphogypsum not only occupies a large amount land, but also seriously harms the surrounding ecological environment. preparation into filling materials for mine can maintain stability rock, reduce subsidence, enhance recovery resources, it completely solve problem stockpiling. Under certain activation conditions, hemihydrate has strong cementing property. It is an important way to cost by using instead cement as material. Through laboratory experiments, based on...

Earth observation systems play important roles in many critical applications. The rapid increase of the number satellites and their sensing capability, however, makes it challenging to send massive amount observed data back Earth. One promising direction enhance earth throughput is use inter-satellite communication. Towards this, we identify two key design factors: 1) capability support on-demand scheduling communication; 2) co-optimize transmission missions. For both, rigorous study needed...

Subjective cognitive decline (SCD) and mild impairment (MCI) carry the risk of progression to dementia, accurate screening methods for these conditions are urgently needed. Studies have suggested potential ability functional near-infrared spectroscopy (fNIRS) identify MCI SCD. The present fNIRS study aimed develop an early method SCD based on activated prefrontal connectivity (FC) during performance scales subject-wise cross-validation via machine learning. Activated FC data measured by were...

To study the influence law of subgrade differential settlement on longitudinal ballastless track (LBT) irregularity considering interlayer contact stiffness randomness, this article adopts LHS to transfer randomness (ICSR) basis previously general representation model deformation and behavior evolution induced by foundation based Castillate's second law. A mapping relationship between LBT ICSR is derived solved. The results relationship, finite element measured data are compared, then...

Powder-fueled ramjets show great potential due to their unique advantages. How further improve ramjet performance through methods such as fuel improvement is also an important focus. In this paper, a 14 km, Ma 3.0, ground test of powder-fueled using boron–aluminum composite powder (B–Al fuel) was conducted. The feasibility and combustion B–Al were verified. Under the condition air–fuel ratio 19.39, achieved independent self-sustaining for 10 s, characteristic exhaust velocity efficiency...

Information-centric wireless network virtualization enables the sharing of not only infrastructure but also content among different service providers, enabling gain in-network caching as well. In this paper, we propose a novel framework with information-centric and device-to-device (D2D) communications, which in air mobile device Moreover, is virtualized can be shared by users from virtual providers. framework, formulate resource allocation strategies joint optimization problem, considering...

SIN is constructed to support real-time data acquisition, massive transmission and processing, systematized information services. Different from static networks, both the network topologies available resources are dynamic in SIN. However, existing networking technologies treat as segmented ignore relationship among different subnetworks, which results low resource utilization poor QoS. This article exploits time-varying graph theory characterize allocate of We first introduce overall...

The application of non-orthogonal multiple access (NOMA) in millimeter wave (mmWave) massive multiple-input multiple-output (MIMO) systems can enhance spectral efficiency. In this paper, we propose an angle-domain NOMA scheme over the multi-cell mmWave MIMO networks. This is optimized through both user scheduling and precoders/decoders design to maximize system sum rate, where precoders are decomposed into outer inner ones. We construct with help users' spatial angle information, i.e., beam...

In this work, we investigate resource allocation strategy for real time communication (RTC) over satellite networks with virtual network functions. Enhanced by inter-satellite links (ISLs), in-orbit computing and virtualization technologies, large-scale promise global coverage at low-latency high-bandwidth RTC applications diversified However, realizing specific function requirements using intermittent ISLs, requires efficient routing methods fast response times. We identify that such a...