scholarly journals A New Hardware Design Scheme of Symbol Synchronization for an Underwater Acoustic Receiver

2011 ◽  
Author(s):  
Li Ying ◽  
Benson Bridget ◽  
Kastner Ryan ◽  
Chen Lan
Keyword(s):  
Hardware Design ◽  
Underwater Acoustic ◽  
Symbol Synchronization ◽  
Design Scheme ◽  
Acoustic Receiver

Automatic Measuring Instrument of Dam Horizontal Deformation Based on Laser Scan Concept

2013 ◽  
Vol 442 ◽  
pp. 372-377
Author(s):  
Jian Yin Lu ◽  
Yun Fei Zhou
Keyword(s):  
Hardware Design ◽  
Deformation Monitoring ◽  
Flow Chart ◽  
Measuring Instrument ◽  
Horizontal Deformation ◽  
Automatic Measuring ◽  
Design Scheme ◽  
Automatic Measuring Instrument ◽  
Dam Deformation

In this paper, a design of an automatic measuring instrument of dam horizontal deformation based on laser scan concept is introduced. According to the demand of the dam deformation monitoring, the design chooses STM32F103CBT6 as the hardware control platform, and the laser scan concept is introduced. The measuring principle, main hardware design scheme and software flow chart are introduced in this paper.

Hardware Design of a Pipeline Inspection Robot

2012 ◽  
Vol 151 ◽  
pp. 116-120
Author(s):  
Hui Zhang ◽  
Li Na Zhao ◽  
Xue Feng Dai
Keyword(s):  
Control System ◽  
Communication Systems ◽  
Robot Control ◽  
Hardware Design ◽  
General Design ◽  
Pipeline Inspection ◽  
Inspection Robot ◽  
Design Scheme ◽  
Carrier Mechanism ◽  
Pipeline Robot

Pipeline robot research has a broad prospect of application and value. Based on the study of the pipeline robot domestic and foreign and in the fully understanding of the questions and intrinsic request of the existing pipeline robot control and communication systems, a general design scheme of wheeled pipeline robot is proposed in this paper, and according to this idea, choice and analysis to the robot is made. After that, the moving carrier mechanism, the components selections and circuits of control system for this pipeline robot are designed in detail.

scholarly journals A software and hardware design scheme of intelligent valve positioner

2021 ◽  
Vol 268 ◽  
pp. 01067
Author(s):  
Haiming Xu ◽  
Lanzhu Zhang
Keyword(s):  
Pid Control ◽  
Control Algorithm ◽  
Hardware Design ◽  
Control Process ◽  
Control Valve ◽  
Pneumatic Control ◽  
Design Scheme ◽  
Valve Stem ◽  
Software And Hardware ◽  
Better Than

Valve positioner is the core component of the pneumatic control valve. A new software and hardware design scheme of intelligent valve positioner is presented in this paper. The circuit composition of each part of the intelligent valve positioner is introduced in hardware part. Based on it, a hardware solution to realize HART ‘multi-point’ communication is proposed in this research. In the software design, a novel combined PID control algorithm is proposed to solve the nonlinear problem caused by the friction between the valve stem and the packing during the control process. Simulation results show that the method proposed in this paper is better than traditional PID method and fuzzy PID method. The software and hardware design scheme of the valve positioner proposed in this paper has certain guiding significance for the development of related products.

scholarly journals Chirp-Based FHSS Receiver with Recursive Symbol Synchronization for Underwater Acoustic Communication

Sensors ◽  
2018 ◽  
Vol 18 (12) ◽  
pp. 4498
Author(s):  
Geunhyeok Lee ◽  
Woongjin Park ◽  
Taewoong Kang ◽  
Kiman Kim ◽  
Wanjin Kim
Keyword(s):  
Acoustic Communication ◽  
Spread Spectrum ◽  
Fractional Fourier Transform ◽  
Signal Frequency ◽  
Underwater Acoustic Communication ◽  
Frequency Variation ◽  
Chirp Signal ◽  
Underwater Acoustic ◽  
Symbol Synchronization ◽  
Compression And Expansion

In this paper, we propose a covert underwater acoustic communication method that is robust to fading using a chirp signal combined with a frequency-hopping spread spectrum scheme. A fractional Fourier transform, which estimates the slope of the signal frequency variation, is applied to the receiver to enable a robust and reliable symbol estimation with respect to the frequency and irregular phase variations. In addition, since the recursive symbol synchronization can be implemented using a chirp signal, compression and expansion effects due to the Doppler shift can be mitigated. Simulation and lake trials were performed to verify the performance of the proposed method. The simulation was performed by two different methods.

Study on the Application of PLC in Coal Sorting System

2014 ◽  
Vol 686 ◽  
pp. 164-168
Author(s):  
Jin E Huang
Keyword(s):  
Production Cost ◽  
Hardware Design ◽  
Coal Production ◽  
The Core ◽  
Design Scheme ◽  
Automatic Sorting ◽  
Core Technology ◽  
System Requirements ◽  
Sorting System ◽  
Control Principle

In order to reduce the coal production cost and labor, PLC is designed as the core technology of coal sorting, and a lot of sensor to distinguish colors and properties of coal join in this system. The sorting effect is very good. PLC coal sorting system has stable, safe, simple, reliable and other advantages, can improve the efficiency of coal production, and has brought the huge profit space for the enterprise. This paper first analyzes the PLC sorting system requirements and functions, and then discusses the control principle of PLC automatic sorting, the total design scheme of automatic sorting and related hardware design analysis, researches and hopes to help PLC coal sorting technology.

scholarly journals Optimized Doppler Estimation and Symbol Synchronization for Mobile M-ary Spread Spectrum Underwater Acoustic Communication

2021 ◽  
Vol 9 (9) ◽  
pp. 1001
Author(s):  
Guang Yang ◽  
Feng Zhou ◽  
Gang Qiao ◽  
Yunjiang Zhao ◽  
Yufei Liu ◽  
...  
Keyword(s):  
Frequency Domain ◽  
Spread Spectrum ◽  
Communication Systems ◽  
Underwater Acoustic Communication ◽  
Horizontal Distance ◽  
Step Size ◽  
Search Range ◽  
Underwater Acoustic ◽  
Symbol Synchronization ◽  
Doppler Factor

In mobile underwater acoustic (UWA) communications, the Doppler effect causes severe signal distortion, which leads to carrier frequency shift and compresses/broadens the signal length. This situation has a more severe impact on communication performance in the case of low signal-to-noise ratio and variable-speed movement. This paper proposes a non-data-aided Doppler estimation method for M-ary spread spectrum UWA communication systems in mobile scenarios. The receiver uses the spread spectrum codes dedicated to transmitting signals with different frequency offsets as local reference signals. Correlation operations are performed symbol by symbol with the received signal. The decoding and Doppler estimation of the present symbol are achieved by searching the correlation maximum in the code domain and frequency domain. The length of the current symbol is corrected for the next symbol synchronization using the estimated Doppler coefficient. To optimize the process of Doppler estimation and symbol synchronization, a heuristic search method is used. By adjusting the Doppler factor search step size, setting the threshold value, and using the Doppler factor estimation of the previous symbol, the search range can be significantly reduced and the computational complexity decreased. The Fisher-Yates shuffle algorithm is used to traverse the search range to ensure reliability of the results. Simulation results show that enlarging the frequency-domain search step size in some degree does not affect the decoding accuracy. On 15 May 2021, a shallow-water mobile UWA spread spectrum communication experiment was conducted in Weihai, China. The horizontal distance between the transmitter and the receiver is 3.7–4.0 km, and the communication rate is 41.96 bits per second. The transmitting ship moves at a speed of 0–3 m/s, and the bit error rate (BER) is lower than 1e−3, which is better than that of the sliding correlation despreading method with average Doppler compensation.

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