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The paper deals with the estimation method of a carrier and time of arrival by chirp-like phase-coded sequence. The developed estimation method of the carrier and time of arrival is suitable for primary synchronization upon signal detection in phase and frequency modulation modems. This method is of less computational complexity relative to the realization of matched filter assembly. To implement...
This paper proposes seamless frequency synchronization scheme for fast mode switching of parallel grid-connected inverters operated by droop control in stand-alone mode to grid-connected mode. The proposed scheme analyzes the phase difference between the grid and the inverter for fast frequency synchronization and predicts the synchronization time for frequency increase and decrease. By selecting...
For a grid-connected Voltage-Source Converter (VSC), dynamics of the grid synchronization plays an important role in affecting the converter performances and stability. Due to its significance, this paper gives a comparative analysis about some basic grid synchronization schemes, through viewpoint of dynamic performances, which appeared as the impacts of voltage perturbation on the estimated angle...
Frequency and voltage regulation are required to support the grid under different scenarios. In order to handle these scenarios, classical control strategies demand complex systems to fulfill these requirements. However, synchronous controllers are trending strategies to contribute with frequency and voltage regulation functionalities without the requirement of external elements. Among these strategies,...
In this paper, we propose a new method to compensate Doppler frequency shift for OFDM-based underwater acoustic communication systems. In order to save bandwidth, we do not use additional signal header (preamble) in each OFDM frame as proposed in many conventional approaches. Instead, the central sub-carrier is reserved for pilot transmission. This subcarrier is so-called as the carrier frequency...
To minimize functional morbidity associated with brain surgery, new preventive approaches (also referred to as "prehabilitation") by using motor-imagery-based computer interfaces (MI-BCIs) can be utilized. To achieve successful MI-BCI performance for prehabilitation purposes, the characteristics of an electrocorticographic (ECoG) signal that is associated with overt motor function ("real...
Mobile ad-hoc networks (MANET) are of particular importance in military communications. With the trend towards higher throughput requirements and spectrum congestion, researchers have looked at using multi-antenna techniques to enable concurrent transmissions within a one-hop MANET. However, the acquisition overhead has been shown to be a problem when dealing with concurrent transmission in MANET...
Since the photovoltaic power generation, wind power and other distributed power supply are volatile and random, they will affect the stability of the grid frequency. In order to improve the voltage and frequency in micro-grid, the virtual synchronous generator control strategy is proposed for inverter control, which can emulate the behavior of synchronous generator, decrease rate of change of frequency...
A method to synchronize a group of microcontrollers with different clock frequencies of their own generator is proposed. The algorithm of each microcontroller operation in the group and the block diagram of the group consisting of N microcontrollers are presented. Timing diagrams of signals of synchronous operation and clock pulses of the microcontrollers group are given. The result of the work, at...
Synchronization has become a main concern in communication and control systems during the last years. Although there are several standard mechanisms to accomplish timing requirements, development and improvement of high synchronization technologies is required to obtain better performance and quality of service. In this context, the enhanced version of IEEE 1588v2 synchronization protocol, known as...
This, paper proposes a method to eliminate the dc component in the measured three-phase grid voltage as the input signals of phase-locked loop (PLL). The dc component in the input signals of PLL causes a low-frequency oscillation of grid frequency. The dc component elimination can be achieved by replacing the integrator in the second-order generalized integrator (SOGI) with a differentiator, named...
In order to ensure the data synchronization between different channels of the same pulse (the first synchronization) and the data synchronization between different pulses of the same channel (the second synchronization) in the pulse acquisition, two design constraints were proposed to ensure the two synchronization. The design constraint of the first synchronized was proposed by hardware structure...
In this paper, we propose a fast predictive resynchronization scheme that allows nodes to rejoin a 802.15.4e TSCH network with which they were previously synchronized. The idea of the scheme comes from the investigation of the internal and external root causes of the clock drift between two nodes--we have identified the causes and proposed a means for its estimation. Based on the prediction of the...
This paper aims to analyze the synchronization phenomena in the system consisting of n identical metronomes on a hanging plate by using the describing function (DF) method, which deals with the driving torque as a discontinuous function of the angle and angular velocity of each metronome. Different from a previous study on the synchronization of the system with the first harmonic of the angle of each...
There are main parameters of synchronization signals stability and methods for their monitoring in packet networks in the article. The principles of monitoring synchronization signals in the LTE network are presented.
For secondary frequency control of power systems with lossless networks, we proposed a method named Power-Imbalance Allocation Control (PIAC) to restore the nominal frequency after a disturbance. PIAC has shown a good transient performance where under a constant power imbalance, the overshoot problem and unnecessary oscillations of frequencies are eliminated. In this paper, we evaluate the performance...
The technique of differential equation solution of device synchronization boundaries of elementary signals (DSBES) at steady state was proposed, which can be used to study DSBES of discrete type. The main important is the determination of the upper estimate of the time of entering DSBES into relationship.
In distributed transmit beamforming, two, or more, spatially separated communications nodes act as elements of an antenna array to beamform common data to a destination node. Spatially separated cooperating nodes synchronize their carrier frequencies and control their transmission phases so that at the destination node the received signals combine constructively. An important example is cooperative...
This paper introduces a novel method for synchronizing two energized AC grids through a fast synchronization machine, which integrates a battery energy storage system (BESS) with a grid-imposed frequency voltage source power converter. The grid-imposed power converter is used to automatically provide the desired amount of power to the synchronous generators, and the BESS is connected to the DC side...
A 450kHz 30kbps all-digital BPSK demodulator is implemented in 65nm CMOS. Correlation and carrier recovery algorithms are designed to be PVT-aware through digital correction. The target BER of 10−6 is achieved through 16 symbol per bit redundancy with 8× oversampling. An 8-bit tunable oscillator is utilized with corresponding frequency and phase locking techniques to maintain packet synchronization...
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