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)...

In this paper, we investigate the outage probability (OP) performance of amplify-and-forward (AF) cognitive hybrid satellite-terrestrial overlay networks (CHSTONs) with non-orthogonal multiple access (NOMA) scheme, in which half-duplexing terrestrial secondary cooperate a primary satellite network for dynamic spectrum access. order to improve fairness paradigm, NOMA-based power allocation profile is determined by instantaneous channel conditions. Considering generalized shadowed-Rician...

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"...

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, we investigate the secrecy performance of multiuser dual-hop relay networks where a base station (BS) communicates with multiple legitimate users through assistance trustful regenerative in presence eavesdroppers. particular, maximal ratio transmission scheme is exploited at BS and threshold-based scheduling employed over users, while concerning imperfect decoding relay. To evaluate considered system, two practical situations are addressed based on availability eavesdropper's...

In this paper, we consider a multiuser downlink wiretap network consisting of one base station (BS) equipped with AA antennas, NB single-antenna legitimate users, and NE eavesdroppers over Nakagami-m fading channels. particular, introduce joint secure transmission scheme that adopts transmit antenna selection at the BS explores threshold-based diversity scheduling users to achieve good secrecy performance while maintaining low implementation complexity. More specifically, in an effort...

In this paper, the performance of non-orthogonal multiple access (NOMA) based cooperative spectrum sharing in hybrid satellite-terrestrial networks (HSTNs) is investigated, where primary satellite network recruits secondary terrestrial as a relay. To improve fairness and utilization under (i.e. overlay paradigm cognitive radio), NOMA power allocation profile determined by instantaneous channel conditioning at second temporal phase. The closed-form outage probability approximated ergodic...

In this paper, we study the multiple-user non-orthogonal multiple access (NOMA) scheme in hybrid satellite-terrestrial relay networks (HSTRN). The proposed system model takes into account both decode-and-forward (DF) and amplify-and-forward (AF) protocols at imperfection of channel state information (CSI) all nodes. We analyze outage performance investigate power allocation problem to ensure fairness among users. Specially, derive closed-form expressions asymptotic high...

Due to the emergence of non-terrestrial platforms with extensive coverage, flexible deployment, and reconfigurable characteristics, hybrid satellite-aerial-terrestrial networks (HSATNs) can accommodate a great variety wireless access services in different applications. To effectively reduce transmission latency facilitate frequent update files improved spectrum efficiency, we investigate performance cache-enabled HSATN, where user retrieves required content from aerial node (AN) or satellite...

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, 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...

In this letter, we investigate the Vickrey auction-based secondary relay selection in cognitive hybrid satellite-terrestrial overlay networks (CHSTONs) with non-orthogonal multiple access (NOMA). We analyze a cooperative spectrum sharing scheme for multi-potential scenario, which auction is introduced to achieve an efficient by one shot within distributed computation. Both decode-and-forward (DF) and amplify-and-forward (AF) protocols are considered retransmit primary user's message,...

A novel low-cost compact patch antenna with capability of beam steering is presented in this letter. The complementary split-ring resonators (CSRR)-loaded ground structure enables the property wide-scale range and can greatly reduce cost a phased-array system to meet requirement wireless communications. Parameter extraction for CSRR investigated analyze effect loading metamaterial on radiation pattern antenna. It shown that refractive index part affects direction. Both single double...

One novel dual‐band dual‐mode dual‐polarisation microstrip antenna with broad bandwidth is designed and analysed in this study. In the lower frequency band, operates dipole mode linearly polarised omnidirectional radiation pattern, whereas upper works patch circularly directional patterns. The of broadened by adding curved parasitical patches around centre radiating which fed capacitive probe. Parameter analysis made to further explore working principle one prototype realised for...

Satellite-based Internet of Things (IoT) is recognized as a cost-effective approach for global access. In this article, we aim at improving the spectrum efficiency satellite systems to serve huge number IoT devices. To end, present cognitive satellite-terrestrial framework, where multibeam system with full frequency reuse shares terrestrial networks based on underlay paradigm. Considering DVB-S2X recommendations, geometric configurations, and channel characteristics, investigate robust...

Constructing an infrastructure for spectrum sensing and sharing on the cloud is a promising technology. In this paper, we propose analysis framework based data gathered by distributed sensors to construct radio environment map (REM). To best of our knowledge, first attempt leverage power Bayesian Markov chain Monte Carlo (MCMC) in REM. Specifically, three-stage hierarchical model (BHM) established imitate generation process under spatially correlated shadow fading. Parameters BHM are...

In this paper, a new method for blind recognition of BCH code from an intercepted sequence noise affected codewords is proposed. The proposed recovers the parameters by finding roots it's generator polynomial. Firstly, Galois Field Fourier Transform (GFFT) operation carried out each estimated length. Then, find positions common zero spectral components all sequences' GFFT. If such exist, corresponding length and underlying polynomial are found. Furthermore, theoretical analysis given in...

In this article, we investigate robust secure beamforming and power splitting for multiuser secondary terrestrial networks with simultaneous wireless information transfer, which coexist primary satellite in the same millimeter-wave bands. particular, a base station is equipped uniform planar array, user (SU) employs power-splitting-type receiver. Under an angle-based channel state (CSI) error model, formulate optimization problem aim to maximize minimal worst-case achievable secrecy rate...

Wireless content delivery (CD) and non-orthogonal multiple access (NOMA) have been confirmed to be promising effective approaches gain substantial performance improvement for hybrid satellite-terrestrial (HST) networks. To improve the spectrum efficiency reduce delay of retrieving satellite user, we investigate HST-CD network with NOMA scheme, where proactively pushes/broadcasts popular contents cache-enabled relay, then user is able directly retrieve required from relay less transmission...

In this article, we introduce a potential game-based approach to implement collaborative user scheduling and power allocation in the uplink multibeam satellite-based Internet of things (S-IoT) networks. First all, framework S-IoT system is proposed, where full frequency reuse co-channel interference among different spot beams are considered. To provide broadband service effectively, formulate an initial optimization problem maximizing sum transmission capacity then transform it into...

A single-feed circular polarized (CP) rectangular microstrip antenna (MPA) is proposed. Capacitive disk coupling feed used in the design. By connecting a resistor load to another capacitive at opposite position, CP radiation over wide frequency range realized. Experimental results show that fabricated has an impedance bandwidth (S <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">11</sub> return loss) of 78.7% and 3-dB axial ratio (AR) 27.5%. The...

The phase-shifting characteristic of a novel composite right/left handed transmission line (CRLH TL) for two frequency points is analyzed in this paper. Samples (90 - , 0 ) and (180 TLs (f1; f2) are deigned the total length CRLH has decreased by more than 77% compared to conventional microstrip lines. Then four way power divider made three Wilkinson dividers interconnected with designed feed an antenna difierent operating modes at bands. Four radiating patches arranging symmetrically loop...

In this paper, we investigate the auction-based secondary relay selection on overlay spectrum sharing in hybrid satellite-terrestrial sensor networks (HSTSNs), where both decode-and-forward (DF) and amplify-and-forward (AF) protocols are analyzed based time division multiple access (TDMA). As primary rational, honest but with incomplete network information, they prefer to obtain maximum possibility payoffs by cooperation between networks, competition among networks. Hence, Vickery auction is...