With the development of navigation satellite constellation systems, to improve navigation service and orbit determination performance, the accuracy requirements for maintaining temporal references have increased rapidly. Among the current navigation...
China developed its Digital Television (DTV) standard in 2006, known as Digital Television Terrestrial Multimedia Broadcasting (DTMB), which employs time-domain synchronous orthogonal frequency division multiplexing (TDS-OFDM) as the modulation metho...
In the optical fiber time transfer system, fiber optic time transfer is limited by the pulse signal time delay measurement precision, and cannot benefit from a higher precision of the carrier phase information. Its transfer precision compared to the...
Compared to traditional phase laser ranging technology, phase-shift laser ranging technology based on carrier phase modulation has significant advantages, such as simple modulation and demodulation, as well as simultaneous ranging and velocity measur...
The low-cost single-frequency GNSS receiver is one of the most economical and affordable tools for the onboard real-time navigation of numerous remote sensing small/micro satellites. We concentrate on the algorithm and experiments of onboard real-tim...
Concerning the triple-frequency ambiguity resolution, in principle there are three different realizations. The first one is to fix all the ambiguities of the original frequencies together. However, it is also believed that fixing the combined integer...
Carrier phase measurement is a ranging technique that uses the receiver to determine the phase difference between the received signal and the transmitted signal. Carrier phase ranging has a high resolution; thus, it is an important research direction...
With the booming development of the Internet of things (IoT) industry, the demand of positioning technology in various IoT application scenarios is also greatly increased. To meet the positioning requirements of the IoT application, we propose a dist...
Microwave photonic phase-shifting technology can be used to generate high-frequency, broadband, and tunable phase-coded microwave signals, which are helpful in solving the contradiction between the detection range and the range resolution in radar sy...
A semiconductor ring laser with a long cavity supports propagating localised structures with a chiral charge, named phase solitons. In this paper we study the dependence of the velocity and of the duration of the phase solitons on the characteristic...
This paper presents a means of carrier phase cycle slip detection for an inertial-aided global positioning system (GPS), which is based on consideration of the satellite geometry. An integrated navigation solution incorporating a tightly coupled tim...
We present analyses of Global Navigation Satellite System (GNSS) carrier phase observations in multiple kinematic scenarios for different receiver types. Multi-GNSS observations are recorded on high sensitivity and geodetic-grade receivers operating...
The features of the local mean and fluctuational flow structure, carrier phase turbulence and the propagation of the dispersed phase in the bubbly and droplet-laden isothermal round polydispersed jets were numerically simulated. The dynamics of the p...
This study used a supported liquid membrane system (SLM) using Celgard 2400 polypropylene as the support, di(2-ethylhexyl) phosphoric acid (D2EHPA) as the carrier, and kerosene as the diluent. To obtain the best carrier concentration, D2EHPA concentr...
We propose an alternative waveform scheme built on mutually-orthogonal complementary sets for a distributed multistatic radar. Our analysis and simulation show a reduced frequency band requirement for signal separation between antennas with centraliz...
A microwave photonic frequency-doubling phase shifter with a broad bandwidth and large tuning range is proposed in this paper. Frequency doubling and phase shifting are realized by processing the input microwave signal in the optical domain at a dual...
Various GNSS applications require low-cost, small-scale, lightweight and power-saving GNSS devices and require high precision in terms of low noise for carrier phase and code observations. Applications vary from navigation approaches to positioning i...
A high-accuracy Global Ionosphere Model (GIM) is significant for precise positioning and navigating with the Global Navigation Satellite System (GNSS), as well as space weather applications. To obtain a precise GIM, it is critical to take both the io...
In this paper, we proposed a reflection phase electrically tunable metasurface composed of an Au/Al2O3/ITO/Au grating structure. This antenna array can achieve a broad phase shift continuously and smoothly from 0° to 320° with a 5.85 V applie...
By the use of the tertiary amine A327 and 1 M HCl solution as precursors, the ionic liquid A327H+Cl− was generated and used to investigate its performance in the transport of Au(III) from hydrochloric acid medium. The influence of the stirring...
The susceptibility of global navigation satellite systems (GNSSs) to interference significantly limits the possibility of their use. From the standpoint of possible consequences, the most dangerous interference is the so-called spoofing. Simultaneous...
In half-bridge converter series microgrid (HBCS-MG) systems, output fluctuations caused by varying wind speeds and solar shading induce active power imbalances among generation modules (GMs). This imbalance increases susceptibility to overmodulation...
Modular multilevel converters (MMCs) are attractive for medium- and high-power motor drive applications; however, low-speed motor operation can cause significant submodule (SM) capacitor voltage ripple. In conventional carrier phase-shifted pulse-wid...
BiCuSeO has great application prospects in thermoelectric power generation and thermoelectric catalysis, but it is limited by its lower thermoelectric performance. Herein, BiCuSeO bulk materials were prepared using a solid-phase reaction method and a...
The structure and mechanical properties of the coatings formed by reactive detonation spraying of titanium in a wide range of spraying conditions were studied. The variable deposition parameters were the nature of the carrier gas, the spraying distan...
The GRACE Follow-On satellite mission measures distance variations between its two satellites in order to derive monthly gravity field maps, indicating mass variability on Earth on a scale of a few 100 km originating from hydrology, seismology, clima...
Using GNSS observable from some stations in the Asia-Pacific area, the carrier-to-noise ratio (CNR) and multipath combinations of BeiDou Navigation Satellite System (BDS), as well as their variations with time and/or elevation were investigated and c...
A low Earth orbiter (LEO)-based navigation signal augmentation system is considered as a complementary of current global navigation satellite systems (GNSS), which can accelerate precise positioning convergence, strengthen the signal power, and impro...
Using a two-carriers model and the Hikami-Larkin-Nagaoka (HLN) theory, we investigate the influence of large area patterning on magnetotransport properties in bismuth thin films with a thickness of 50 nm. The patterned systems have been produced by m...
This paper designs a cascading vector tracking loop based on the Unscented Kalman Filter (UKF) for high dynamic environment. Constant improvement in dynamic performance is an enormous challenge to the traditional receiver. Due to the doppler effect,...
Tracking error estimation is of great importance in global navigation satellite system (GNSS) receivers. Any inaccurate estimation for tracking error will decrease the signal tracking ability of signal tracking loops and the accuracies of position fi...
Primary angular vibration calibration devices based on laser interferometers play a crucial role in evaluating the dynamic performance of inertial sensing devices. Here, we propose a sinusoidal phase-modulated angle interferometer (SPMAI) to realize...
Recent studies indicate that the stereo-ATI carrier-envelope phase meter (CEPM) is an effective method to determine the carrier-envelope phase (CEP) of each and every single few-cycle laser pulse. In this method, a two-dimensional parametric asymmetr...
Due to the influence of indoor space environments, the carrier phase information obtained by the BeiDou pseudo-satellite often has the issue of cycle slips, which makes the user unable to carry out high-precision positioning. Aiming at the problem of...
In this manuscript, we report on a 1 × 4 optical beam forming network (OBFN) chip using optical phase shifters (OPSs) based on thermo-optically controlled optical ring resonators (ORRs) for 1D beam steering at 0.3 THz. The 1 × 4 OBFN chip...
Electric variable speed drives (VSD) have been replacing mechanic and hydraulic systems in many sectors of industry and transportation because of their better performance and reduced cost. However, the electric systems still face the issue of being c...
This paper proposes a cooperative localization method based on time-division processing of interferometric measurements, in which the receiver updates the signals from multiple UAVs in separate time slots, thereby reducing spectrum usage and baseband...
Fast and reliable ambiguity resolution (AR) has been a continuing challenge for real-time precise positioning based on dual-frequency Global Navigation Satellite Systems (GNSS) carrier phase observation. New GNSS systems (i.e., GPS modernization, BDS...
A common-mode voltage (CMV) suppression strategy, namely double zero-sequence injection common-mode voltage (DZICMV), is proposed in this paper for an asymmetrical six-phase induction motor fed by two-level dual three-phase voltage source inverters (...
This paper presents a wide-range and low phase noise mm-Wave Voltage Controlled Oscillator (VCO) based on the transconductance linearization technique. The proposed technique eliminates the deep triode region of the active part of the VCO, and lowers...
In recent years, low-Earth-orbit (LEO) constellations have been proposed for Positioning, Navigation and Timing (PNT) applications. Moreover, a couple of test satellites have already been launched and many more are scheduled in the near future. LEO c...
The removal of chromium(VI) from an acidic (HCl) medium through non-dispersive extraction with strip dispersion (NDXSD) was investigated using a microporous PVDF membrane support in a permeation cell. The ionic liquid Cyphos IL102 (phosphonium salt)...
Modular multilevel converter (MMC)-based HVDC systems have become one promising way to integrate a large amount of renewable energy. However, the high-frequency harmonics problem could seriously affect the safety and stable operation level of MMC-HVD...
The GRACE follow-on satellites carry the very first interspacecraft Laser Ranging Interferometer (LRI). After more than four years in orbit, the LRI outperforms the sensitivity of the conventional Microwave Instrument (MWI). However, in the current d...
The critical phenomena of double percolation on polybutadiene (PB)/polyethylene glycol (PEG) blends loaded with poly-3-hexylthiophene (P3HT) nanofibers is investigated. P3HT nanofibers are selectively localized in the PB phase of the PB/PEG blend, as...
The switching frequency of high-power inverters, such as those used in rail transit traction systems, is low, due to switching loss and heat dissipation limitations. This can result in considerable output voltage harmonics. This paper proposes an opt...
In view of reducing the number of inverter legs that provide dual-phase, three-level output voltages (as may be needed in an uninterruptible power supply), and that also provide a wide range of output frequencies (as needed in an advanced motor drive...
This paper proposed a 5.42~6.28 GHz type-II phase locked loop (PLL) for the sake of both loop filter switching capability and extensive programmability. An on-chip loop filter is used in conjunction with off-chip one to form a switching filter pair f...
A frequency stabilization scheme for a wideband-tunable optoelectronic oscillator (OEO) based on fundamental and subharmonic RF injection locking is proposed, achieving a tuning range of 2–22 GHz with low phase noise. The injection-locked perfo...
Photo-excited charge carriers play a vital role in photocatalysts and photovoltaics, and their dynamic processes must be understood to improve their efficiencies by controlling them. The photo-excited charge carriers in photocatalytic materials are u...
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