This correspondence develops a physical-layer security scheme for cognitive-satellite terrestrial network, where the satellite and base station (BS) share spectrum resource, multiple eavesdroppers attempt to intercept private signal from BS mobile user. Different commonly used passive reconfigurable intelligent surface (RIS), active RIS, whose reflecting elements can control both amplitude phase of incident signal, is deployed cooperatively enhance secure transmission user, suppress...

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...

In this letter, we investigate the optimization in a simultaneously transmitting and reflecting reconfigurable intelligent surface-enabled network with coupled coefficient model, where transmit beamforming (BF) coefficients (TRCs) are jointly designed. Our goal is to maximize weighted sum rate for multiple users, subject discrete constraint. To solve nonconcave objective, develop an alternating method, BF can be obtained closed form by bisection TRCs solved elementwise approach. Simulation...

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...

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,...

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...

The resource allocation strategy is a critical problem in the low earth orbit (LEO) satellite communication network (SCN) due to limited resources and high movement. In this letter, we first introduce rental service into LEO-SCN improve utilization by renting out unused resources. Secondly, investigate prediction-based matching scheme for rentable LEO-SCN. Specifically, long-short-term memory (LSTM) based prediction framework developed predict traffic value of local tasks, which affected...

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...

In this survey paper, we first provide insights on the evolution of radio access networks (RANs) through investigating existing paradigms and future trends towards 6G. We then present fully-decoupled RAN (FD-RAN), which aligns with by integrating introducing new features such as physical decoupling uplink downlink base stations. also discuss key technologies enabled different architectures for further performance improvement some open issues. hope that can stimulate more in-depth research...

Frequency estimation of a single complex exponential waveform is an important problem in many fields. In this letter, new frequency estimator for sine observed under the additive white Gaussian noise (AWGN) proposed. The proposed obtained by solving nonlinear functions. has analytical expression based on interpolation method with three DFT samples. Numerical results demonstrate that performance lower SNR threshold to closely reach Cramer-Rao bound (CRB) low region and its also outperforms...

In this paper, a parallel concatenated structure is proposed to improve the performance of polar codes in finite length which multiblocks systematic (SPC) and recursive convolutional (RSC) are combined. We first design weighted iterative decoding algorithm for such that better bit error rate can be obtained. Then, deliberated interleaver optimized new scheme. Thereafter, we introduce strategy estimate minimum distance concatenation codeword, where an asymptotic convergence behavior analysis...

Faster-than-Nyquist (FTN) signaling is regarded as a potential modulation format of 5G communication system for its high spectral efficiency. To further improve the efficiency, researchers have extended FTN to frequency dimension. However, two-dimensional called multicarrier (MFTN) induces intersymbol interference and intercarrier (ICI), which challenges receiver. Even subcarriers are orthogonal, MFTN still ICI. In this paper, we propose new transceiver with an mapper linear minimum mean...

Pseudo-satellite technology has excellent compatibility with the BDS satellite navigation system in terms of signal systems. It can serve as a stable and reliable positioning source signal-blocking environments. User terminals achieve continuous high-precision both indoors outdoors without any modification to module. As result, pseudo-satellite indoor gradually emerged research hotspot field. However, due complex variable radio propagation environment, is interfered by noise, multipath,...

To address the challenge of optimizing layout pseudolite anchor points in complex indoor environments with significant occlusions, this paper proposes a multi-objective particle swarm optimization algorithm (MG-MOPSO). The leverages minimum geometric dilution precision (GDOP) configuration to optimize deployment, aiming meet high-precision requirements positioning systems. Experimental results show that compared standard MOPSO, MG-MOPSO improves convergence speed two objective functions by...

In low earth orbit (LEO) satellite networks, because the speed of LEO is much faster than that mobile node, a unable to provide services for user continuously. order ensure user's communication will not be interrupted, satellites service users one by one. this paper, based on weighted bipartite graph in we proposed an access and handover strategy links between users. The quality can regarded as weight edge graph, which multi-objective optimization problem. Since problem can't make all...

This letter proposes a satellite handover strategy for the huge low earth orbit (LEO) constellation. As increasing of constellation scale and number user terminals (UTs), becomes more complicated. Thus, we formulate network-flows model handover, UTs can access satellites according to flow matrix. In proposed model, weighted edges are determined by requests quality services. The multiple matching between be calculating minimum cost maximum network-flows. Besides, propose modified based on...

In this paper, two minimum mean-squared error (MMSE) turbo equalization and detection schemes for spectral efficient multicarrier faster-than-Nyquist (MFTN) signaling system are presented. First, the two-dimensional (2-D) soft input output (SISO) MMSE intended magnetic recording channels, i.e., 2-D intersymbol interference (ISI), is extended to of MFTN signals. Although exhibits an attractive bit-error-rate (BER) performance under certain time-frequency spacing packing between adjacent...

Since the signals of global navigation satellite system (GNSS) are blocked by buildings, accurate positioning cannot be achieved in an indoor environment. Pseudolite can simulate similar outdoor and used as a stable reliable signal source environments. Therefore, it has been proposed good substitute become research hotspot field positioning. There still some problems pseudolite field, such as: Integer ambiguity carrier phase, initial position determination, low coverage. To avoid limitation...

Multicarrier faster-than-Nyquist (MFTN) is a spectral efficient transmission scheme for future communication systems. However, as one of the most important drawbacks multicarrier systems, peak-to-average power ratio (PAPR) MFTN signals still not clear yet. In this paper, we investigate PAPR nonlinear satellite First all, distribution under various practical situations evaluated, and show that closely related to number subcarriers, shaping pulse, time–frequency packing factors. Moreover,...

Multicarrier faster-than-Nyquist (MFTN) signaling is a spectral efficient transmission scheme for future communication systems. Similar as general multicarrier signals, the high peak-to-average power ratio (PAPR) also one of main drawbacks MFTN signals. Unfortunately, PAPR problem in system has rarely been considered literatures. In this paper, we investigate reduction First, derive an inverse fast Fourier transform (IFFT)-based implementation transmitter. Based on which, novel partial...