As lithium niobate shows good biocompatibility plus pyroelectric and photovoltaic effects, it is of interest for lab-on-a-chip biomedical applications. In this context, its most important function would be controlling microdroplets via light-induced changes in material properties. Most investigations, however, have involved...

Unmanned aerial vehicles (UAVs) are used in different scenarios. The need for intelligent and accurate recognition of targets using UAV-based radars is increasingly urgent. As unique information targets, micro-Doppler characteristics have become an important basis target recognition. For three typical ground including pedestrians, wheeled vehicles, tracked the modulation UAV vibration on echo signals analyzed first this article. Second, singular value decomposition (SVD) adopted to suppress...

Commonly used robot map models include occupancy grid maps, topological and semantic maps. Among these, an is mainly represented as a quadrilateral grid. This paper proposes information for intelligent robots by exploiting the advantages of spatial In terms geometric structure, regular hexagonal instead attribute single obstacle replaced terrain characteristics, element attributes, edge attributes. Thus, model transformed into new data structure describing environment, it can be effectively...

The rapid development of flight control technology has made unmanned aerial vehicles (UAVs) widely used in high-precision strikes on the battlefield. premise this is to achieve accurate target recognition using UAV-based radars. Aiming at three typical ground targets, including pedestrians, wheeled vehicles, and tracked micro-Doppler modulation caused by random vibration UAV analyzed article for first time. To improve accuracy under low signal-to-noise ratios (SNRs), Doppler signals are...

In recent years, blind deconvolution has been widely used in machinery condition monitoring and proved to be an effective method for impact detection. Considering that the ultra-wideband measuring system adopts Gaussian impulses as transmitting signal, improved algorithm explained this paper extracts UWB impulse series from mixture of real noise, jamming signals. Then, ability entropy characterize is investigated improve deficiency traditional methods which depend on kurtosis. Last but not...

The presence of blanket jamming, a typical form airborne synthetic aperture radar (SAR) causes incoherent signals with strong power to enter the SAR receiver, which significantly reduces signal-to-noise ratio (SNR) images and dramatically influences imaging effect SAR. In this manuscript, an anti-blanket interference algorithm based on fractional order Fourier transform (FRFT) second blind identification (SOBI) is proposed. Firstly, geometrical model for under condition developed. Then,...

Ultra-wideband (UWB) radio technique, due to its potential applications and great detection ability, is vulnerable electromagnetic interference that cannot be ignored. With the improvement maturity of digital frequency memory (DRFM) technology, a new type active deception jamming, which has similar features in time or domain with transmitted signals, poses greater risk UWB detectors compared conventional suppressive jamming. Therefore, antijamming become critical study, how recognize jamming...

Impulse radio ultrawideband (IR-UWB) radar has the advantages of low cost, high resolution, and independence light weather conditions. Its potential in human activity recognition (HAR) for IoT device sensing draws interest. One challenge this domain is effectively representing spatial static temporal dynamic information echo sequences. Transformers, used extensively NLP CV, have powerful sequence long-range dependency modeling capabilities. However, field HAR, application research...

Temperature field simulation for self-healing power capacitor makes sense to the optimization and improvement of capacitor's rated voltage capacity. On basis reasonable simplifications assumptions structure, a 3-D temperature numerical model is formulated in Fluent 15.0. The ambient set 55 °C, applied ac 400 V. distributions shell core are obtained. results reveal that 2 °C-3 °C higher than shell. highest locates on large side surface, surface small surface. To validate above simulation,...

Ultrawideband (UWB) impulse radio system has received extensive attention due to their high resolution and poor interception possibility. But the specific electromagnetic threat posed by its complex work environment cannot be ignored. In all kinds of active jamming signals, smart noise (SNJ) plays an important role in modern radar electronic warfare, most traditional antijamming methods have less suppression effect. this article, mechanism SNJ on UWB ranging sensor is discussed first. On...

In this work, a novel kind of interesting spectral change, multiple switches, is revealed for the first time. During analysis evolution scattered spectrum newly proposed electromagnetic random source circular frame upon semisoft boundary medium in far zone, it shown that, with appropriate system parameters, would present unique double-peak configuration, which well-known switch. When further increase scattering angle, to our great surprise, switches may repeat several times, effect we define...

In this study, an ultra-thin CPW-fed ultra-wideband flexible MIMO antenna for Internet of Things (IoT) applications is proposed. The etched on a liquid crystal polymer (LCP) substrate. Two elements the presented are placed parallelly without isolator. measured S11 less than −6 dB from 4.7 to 45 GHz, covering China's 5G and millimeter-wave bands. S21 −20 in most bands except 8.5–11.7 minimum |S21| 15.7 at 10.5 GHz. addition, simulation measurement results indicate antennas have good radiation...

To address the problems of cumbersome processes, large data, and error accumulation in calculation conventional GNSS precipitable water volume (PWV), multi-factor PWV conversion models were established using multiple linear regression fitting method. This paper analyzed correlation between zenith tropospheric delay (ZTD), surface temperature (T), atmospheric pressure (P) based on data from 38 stations China region 2017 to 2018. The research results showed that mean deviation one-factor model...

Variable-weight optical orthogonal code (OOC) was introduced by G-C Yang for multimedia CDMA systems with multiple quality of service (QoS) requirement. In this paper, a construction optimal (v, {3, 4}, 1, {s/(s+1), 1/(s+1)})-OOCs is given. For s = 2, it proved that each prime v ≡ 1 (mod 24), there exists {2/3, 1/3})-OOC. A recursive cyclic difference family also presented. By using these constructions, number new infinite classes Q)-OOCs Q {1/2, 1/2} and 1/3} are constructed.

As an important feature of target identification and detection, micro-doppler has been widely used in various fields land, sea air, become a research hotspot. This paper analyses the model ships by combining complex fretting form ship motion from which deduces characteristics expressions ships. Then, after time-frequency analysis, oscillation frequency parameters curve are extracted hough transformation(HT) under low signal-to-noise ratio (SNR) . It is consistent with ship's rocking...

The influences of on-resistances and parasitic elements on the static current sharing N-paralleled discrete silicon carbide (SiC) MOSFETs are analyzed in this paper. First all, limitation self-balancing effect caused by positive temperature dependent on-resistance is quantitatively analyzed. From a statistical analysis, distribution according to spread presented, which helps screen proper devices based requirement. Furthermore, general circuit model proposed analyze inevitable with given...

Electromagnetic threats the carrier-free ultrawideband (UWB) sensors face cannot be ignored. However, it is difficult to tackle various jamming signals well by using one type of suppression algorithm with development technology. To solve this issue, an anti-jamming model based on equivalent sampling and coupled chaotic oscillator proposed in letter. First, echo data collected sampling, which can destroy features time domain. Therefore, does not require extra attention initial form during...

A compact coplanar waveguide-fed triple-band multiple input output (MIMO) antenna is designed based on flexible substrate named liquid crystal polymer in this work. The proposed comprises two elements placed side by side. By adding a double Y-shaped branch between elements, good isolation achieved successfully, which better than 21 dB. According to the measured results, it can operate bandwidth covering 2.263–2.925, 3.063–4.5 and 4.588–7.25 GHz, meeting radio spectrum, including 5G, WLAN...

Variable-weight optical orthogonal code (OOC) was introduced by G-C Yang for multimedia CDMA systems with multiple quality of service (QoS) requirement. In this paper, it is proved that each prime v ¿ 1 (mod 24), there exists a (v, {3, 4}, 1, {2/3, 1/3})-OOC.