A novel reconfigurable microstrip antenna with radiation pattern selectivity and polarization diversity is presented in this letter. four-way power divider made by three Wilkinson dividers interconnected switches (currently copper strips for proof of concept) designed to feed antenna. By controlling the states switches, characteristics can be changed into two modes. When four rectangular radiating patches are excited sources equal amplitude phase, a metamaterial conical beam linear (LP)...

(Aim) Abnormal breast can be diagnosed using the digital mammography. Traditional manual interpretation method cannot yield high accuracy. (Method) In this study, we proposed a novel computer-aided diagnosis system for detecting abnormal breasts in mammogram images. First, segmented region-o f-interest. Next, weighted-type fractional Fourier transform (WFRFT) was employed to obtain unified time-frequency spectrum. Third, principal component analysis (PCA) introduced and used reduce spectrum...

Aim: To detect pathological brain conditions early is a core procedure for patients so as to have enough time treatment. Traditional manual detection either cumbersome, or expensive, time-consuming. We aim offer system that can automatically identify images in this paper. Method: propose novel image feature, viz., Fractional Fourier Entropy (FRFE), which based on the combination of Transform (FRFT) and Shannon entropy. Afterwards, Welch’s t-test (WTT) Mahalanobis distance (MD) were harnessed...

Low Earth orbit (LEO) satellite is one of the most promising infrastructures for realizing next-generation global wireless networks with enhanced data rates. Applying massive multiple-input multiple-output (mMIMO) to LEO communication systems a novel idea enhance capacity and realize high-speed interconnection. However, obtaining effective instantaneous channel state information (iCSI) challenging due time-varying propagation environment long transmission delay. In this letter, deep learning...

Wavelet transform is widely used in feature extraction of magnetic resonance imaging. However, the traditional discrete wavelet (DWT) suffers from translation variant property, which may extract significantly different features two images same subject with only slight movement. In order to solve this problem, paper utilizes stationary (SWT) instead DWT. Experiments on a normal brain MRI demonstrate that coefficients via SWT are superior those DWT, terms invariant property. addition, we...

Cyclic redundancy check (CRC) assisted list successive cancellation decoding (SCLD) makes polar codes competitive with the state-of-art codes. In this letter, we try to find optimal CRC for further improve its performance. We first analyze undetected error probability of CRC-aided SCLD as well characteristics Hamming weight distribution Based on these characteristics, a multilevel SCLD-based searching strategy moderate size is proposed compute minimum (MHWD) different CRC-concatenated Using...

In this communication, a planar beam scanning substrate integrated waveguide (SIW) slot leaky-wave antenna (LWA) is proposed for enhancing range and gain flatness using modified composite right/left-handed transmission line (CRLH TL) structure. The curved phase-shifting characteristics of the CRLH TLs positioned between radiation slots are adopted to increase antenna. Compared with conventional SIW LWAs, offers less variation due its better balance left-handed right-handed bands sensitivity...

Microstrip patch antenna with multi-frequency and dual-mode is presented in this communication. The introduction of metamaterial substrate made modified mushroom-type electromagnetic band-gap (EBG) structure enables the multi- functions. composite right/left-handed transmission line (CRLH TL) theory multi-conductor (MTL) are introduced to analyze design kind antenna. Three modes including one monopolar radiation pattern <i xmlns:mml="http://www.w3.org/1998/Math/MathML"...

Non-orthogonal multiple access (NOMA) has the potential to provide higher throughput than conventional orthogonal (OMA), which been considered as a key technology for 5G. NOMA in satellite communication system can anytime, anywhere with improved spectral efficiency and capacity because of its ubiquitous coverage. However, characteristics channels are different from that terrestrial network, i.e., huge time delay Doppler shift. In this paper, existing works, mainly focus on performance static...

Satellite-enabled army Internet of Things (SaIoT) has drawn increasing attention due to the wide-coverage and large-capacity transmission. However, smart jamming based on artificial intelligence technologies seriously degraded SaIoT performance. Thus, this article investigates distributed dynamic anti-jamming scheme for decrease energy consumption in environment. First, a hierarchical Stackelberg game (HASG), which consists leader subgame jammers follower devices, is proposed formulate...

In this letter, we consider non-orthogonal multiple access (NOMA) applying into massive input output (mMIMO) low earth orbit (LEO) satellite communication system (SCS) to improve spectral efficiency. Specifically, investigate sum rate maximization problem with transmit power, quality of service (QoS) constraints, imperfect successive interference cancelation (SIC) and channel state information (CSI) considered. We decouple the original two parts: precoding vectors design power optimization....

As an important part of satellite communication network, LEO constellation network is one the hot research directions. Since nonuniform distribution terrestrial services may cause inter-satellite link congestion, improving load balancing performance has become key issues that need to be solved for routing algorithms in network. Therefore, by expanding range available paths and combining congestion avoidance mechanism, a algorithm based on extended states proposed. Simulation results show...

Low-Earth orbit (LEO) satellites are recognized as one of the most promising infrastructures for realizing global Internet Things (IoT) services. With explosive growth user terminals (UTs) and data traffic, integration massive multiple-input multiple-output (mMIMO) techniques LEO satellite communication systems has been regarded a novel idea to enhance system capacity realize seamless high-speed interconnection. However, obtaining effective downlink channel state information (CSI)...

We investigate a computing task scheduling problem in space–air–ground integrated network (SAGIN) for Internet of Remote Things (IoRT). In the considered scenario, unmanned aerial vehicles (UAVs) collect tasks from IoRT devices and make offloading decisions, which can be computed at UAVs or offloaded to low Earth orbital (LEO) satellite. The optimization objective is design strategies each UAV that maximum number satisfies delay constraint reduces energy consumption UAVs. formulate this as...

As an emerging technology, mobile edge computing (MEC) network paradigm provides great potential for services, which has been widely applied in friendly city environment. However, there are still many challenges to deploy MEC technology harsh tactical communication environment due poor conditions, limited computational resources, and hostile malicious interference. Thus, this article investigates the resource pricing task offloading strategy ad-hoc network, consists of multiple nodes, ground...

A novel broadband high gain periodic endfire antenna is presented. Broad bandwidth realized by using a parallel strip line (PSL) feed and bowtie dipole elements while enhancement achieved loading split-ring resonator (SRR) structure in the direction. The measurements show that SRR-loaded presents of about 6.2~9.9 dB whole working band (5.1~8.2 GHz), which 1.3~4.2 more than unloaded one. This can be used wireless communication systems for its advantages broad gain.

A broadband high-gain periodic endfire antenna is presented in this letter. The gain enhancement achieved by loading with an I-shaped resonator (ISR) structure the direction. Parameter extraction for I-shape unit-cell investigated to analyze its effect on value of antenna. Finally, both ISR-loaded and unloaded one are fabricated verify predictions. measurements show that presents about 6.5-9.5 dB whole working band (about 5.1-8.3 GHz), which 1.5-3.5 more than one. advantages broad bandwidth...

In this paper, a concatenated coding scheme based on polar codes and LDPC is proposed for the additive white Gaussian noise (AWGN) wiretap channel. We first analyze bit error rate (BER) performance of through density evolution (DE). Then, security gap that our can achieve investigated. Finally, to adapt dynamic environments, we present transmission using compatible Polar-LDPC codes. Numerical results suggest more effective flexible than other existing secure schemes.

In this article, we investigate max completion time optimization for Internet of Things (IoT) in LEO satellite-terrestrial integrated networks (STINs), which IoT devices use non-orthogonal multiple access (NOMA) scheme to transmit data central earth stations (CESs), and orthogonal (OMA) is used transmission from CESs satellite. We decouple problem into two subproblems: 1) terrestrial 2) among satellite beams. Different the existing works about NOMA networks, propose a cooperative scheme,...

In this paper, we investigate non-orthogonal multiple access (NOMA) based average age of information (AoI) in LEO satellite-terrestrial integrated networks. Two-user NOMA scheme is used terrestrial networks and several satellites provide orthogonal for the rest users to update status packets. Firstly, closed-form expressions AoI satellite channels are derived with block error rate. Then, minimization problem decomposed into two parts: 1) 2) among satellites. first part, a base...

A novel dual-band microstrip antenna with omnidirectional circularly polarized (CP) and unidirectional CP characteristic for each band is proposed in this communication. Function of dual-mode realized based on loading metamaterial structure. Since the fields fundamental modes are most concentrated fringe radiating patch, modifying geometry patch has little effect radiation patterns two ( <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">n</i> = 0, +...

In this paper, a modified belief propagation (BP) polar decoder is proposed. Unlike the orignal BP decoders, check node added to each of proposed decoder. decoding, propagated messages nodes are by multiplying from nodes, so as enhance reliability these messages. Numerical results show that achieves better performance than original only at cost some additional multiplications, which indicates its effectiveness.

In this paper, planar beam scanning substrate integrated waveguide (SIW) slot leaky-wave antennas (LWAs) are proposed for gain enhancement using a metallic phase correction grating cover. Unlike conventional Fabry-Pérot (FP) cavity antennas, the antenna is fed by SIW LWA instead of feeding antenna. The angle range enlarged meandering entire structure and enhanced cover acting as 1-D lens. Two kinds gratings with different metal strip parameters designed analyzed. operating at center...