scholarly journals Analysis of the Multiplexing Method of New System Navigation Signals of GPS III First Star L1 Frequency in China’s Regional

Sensors ◽  
2019 ◽  
Vol 19 (24) ◽  
pp. 5360
Author(s):  
Hongjun Ye ◽  
Xiaojun Jing ◽  
Liang Liu ◽  
Shuo Hao ◽  
Baoguo Yu
Keyword(s):  
Signal Transmission ◽  
Phase Relationship ◽  
Monitoring And Evaluation ◽  
Signal Acquisition ◽  
Power Ratio ◽  
Signal Modulation ◽  
Modulation Mode ◽  
Gps Satellites ◽  
Nonlinear Amplifiers ◽  
New System

Compared with the previous GPS satellites, the first GPS III satellite adds a new civil signal L1C to the signal components of the L1 frequency in addition to the improvement of positioning accuracy, anti-interference ability, and service life. The selection and combination of signal modulation and multiplexing methods will affect the power ratio and phase relationship in the process of signal transmission. In the distribution of constellation of different modulation modes, the signal amplitudes of different signal constellation points will be affected by the nonlinear amplifiers of satellites. The analysis can assess its impact on navigation performance. The iGMAS monitoring and evaluation center of the 54th Research Institute of China Electronics Technology Group Corporation uses the low-distortion data acquisition and processing platform and refined signal software receiving processing algorithm of the iGMAS monitoring and evaluation center to complete the signal acquisition of the first satellite of GPS III over China, and processes accordingly for its signal modulation mode. Compared with the previous generation GPS of old system signals, it is found that the GPS signal of the new system not only adds the L1C frequency, but also the constant envelope multiplexing mode of the L1 frequency signal, and the power ratio of the internal signal components are also adjusted.

scholarly journals Analysis of Quasi-Zenith Satellite System Signal Acquisition and Multiplexing Characteristics in China Area

Sensors ◽  
2020 ◽  
Vol 20 (6) ◽  
pp. 1547
Author(s):  
Hongjun Ye ◽  
Xiaojun Jing ◽  
Liang Liu ◽  
Maolei Wang ◽  
Shuo Hao ◽  
...  
Keyword(s):  
Data Processing ◽  
High Precision ◽  
Signal Transmission ◽  
Monitoring And Evaluation ◽  
Satellite System ◽  
Assessment System ◽  
Single Frequency ◽  
Modulation Method ◽  
Signal Acquisition ◽  
Observation Data

On the basis of realizing regional navigation, the Quasi-Zenith Satellite System (QZSS) has advanced navigation function, which leads to the broadcasting of more signals in a single frequency of QZSS signals. Current signal transmission technology cannot solve this problem, so it is necessary to design a signal multiplexing method. The current QZSS satellite interface document does not disclose the multiplexing modulation method of the signal transmission, which has a certain impact on the acquisition of high-precision observation data and further data processing. The iGMAS (International GNSS Monitoring & Assessment System) Monitoring and Evaluation Center of the 54th Research Institute of China Electronics Technology Group Corporation has used the low-distortion data acquisition and processing platform and refined signal software receiving processing algorithm of the iGMAS to complete the signal acquisition and analysis of QZSS satellites. Analysis of the multiplexing and modulation method and signal characteristics for the QZSS has been carried out, which can provide a reference for the design and data processing of high-precision receivers.

Design and Implementation of OFDM Baseband Transmission System Based on CORDIC Algorithm and Pipeline FFT

2012 ◽  
Vol 190-191 ◽  
pp. 962-967
Author(s):  
Jun Yang ◽  
Hong Wei Ding ◽  
Ga Zhao ◽  
Ping Ping Shu
Keyword(s):  
High Speed ◽  
Transmission Rate ◽  
Adaptive Modulation ◽  
Signal Transmission ◽  
Transmission System ◽  
Cordic Algorithm ◽  
Clock Frequency ◽  
Modulation Mode ◽  
Baseband Signal ◽  
High Flexibility

This paper designed an OFDM baseband signal transmission system, which adopted CORDIC algorithm, pipeline organization and high-speed floating-point butterfly unit to complete the customized FFT Processor, and the modulation of the signal was realized by enhancing modulation mode (64-QAM) in the adaptive modulation mode. Meanwhile, due to FPGA technology is reconfigurable and parallel, the signal has a higher transmission rate. The system used FPGA resources reasonably and integrated highly, simplifying the complexity of the system; eventually it was adapted to the EP2C35F672C6 chip of Altera, and can be normally operated in the clock frequency of 100 MHz; At the same time, this system the system has high flexibility and generality, simple structure, and good clutter suppression, so it has a certain application prospects.

scholarly journals PAPR Reduction of OFDM Signals by Novel Global Harmony Search in PTS Scheme

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Hojjat Salehinejad ◽  
Siamak Talebi
Keyword(s):  
Smart Grids ◽  
Orthogonal Frequency Division Multiplexing ◽  
Signal Transmission ◽  
Harmony Search ◽  
Average Power ◽  
Wind Farms ◽  
Papr Reduction ◽  
Power Ratio ◽  
Frequency Division ◽  
Ofdm Signals

The orthogonal frequency division multiplexing (OFDM) modulation technique is one of the key strategies for multiuser signal transmission especially in smart grids and wind farms. This paper introduces an approach for peak-to-average power ratio (PAPR) reduction of such signals based on novel global harmony search (NGHS) and partial transmit sequence (PTS) schemes. In PTS technique, the data block to be transmitted is partitioned into disjoint subblocks, which are combined using phase factors to minimize PAPR. The PTS requires an exhaustive search over all combinations of allowed phase factors. Therefore, with respect to the fast implementation and simplicity of NGHS technique, we could achieve significant reduction of PAPR.

Intelligent Health Monitoring System for a Railway Cable-Stayed Bridge

2010 ◽  
Vol 148-149 ◽  
pp. 1390-1393
Author(s):  
De Shan Shan ◽  
Peng Yan ◽  
Zhen Hua Wang
Keyword(s):  
Information Processing ◽  
Monitoring System ◽  
Health Monitoring ◽  
Signal Transmission ◽  
Structural Safety ◽  
Signal Acquisition ◽  
Processing Technologies ◽  
Health Monitoring System ◽  
Cable Stayed Bridge ◽  
Long Span

Intelligent health monitoring system of the long-span railway cable-stayed bridge requires the comprehensive knowledge of instrumentation, analytical and information processing technologies with the knowledge and experiences in design, construction, operation and maintenance of railway cable-stayed bridge for long-term monitoring the performance throughout its lifecycle. It is necessary to perform sensor-based structural monitoring for identifying the bridge conditions in order to assure the structural safety and to evaluate the operational performance. The considerations for deploying a proper monitoring system are appropriate sensor instrumentation, robust signal acquisition, reliable signal processing, and intelligent signal and information processing. The experience on developing an autonomous monitoring system in the one certain railway cable-stayed bridge newly constructed is introduced in this paper. Sensor and hardware instrumentation, signal transmission, signal acquisition and analysis are schematically described mainly. Experience through this work will be worthwhile lessons for other similar efforts.

An Improved QPSK Signal's Algorithm Design and Simulation of its Modulation and Demodulation

2014 ◽  
Vol 912-914 ◽  
pp. 1146-1149
Author(s):  
Fan Zhou ◽  
Xin Xin Geng ◽  
Xiao Yu Zhang
Keyword(s):  
High Frequency ◽  
Satellite Communication ◽  
Algorithm Design ◽  
High Frequency Band ◽  
Signal Modulation ◽  
Software Simulation ◽  
Modulation And Demodulation ◽  
Modulation Mode ◽  
Depth Analysis ◽  
Simulation Testing

QPSK, a modulation mode with a high frequency band utilization ratio and a strong anti-noise immunity,is widely used in the field of military and satellite communication. This article based on the analysis of the traditional QPSK signal modulation and demodulation mechanism, proposes an improved QPSK signal modulation and demodulation algorithm, and have a further in-depth analysis of the feasibility of this algorithm. Finally, by MATLAB software simulation testing, simulation results shows that the algorithm can accurately generate a QPSK signal and complete a rapidly demodulation of a QPSK signal.

scholarly journals Error-correcting Coding Usage for Data Transmission Through Power Lines

2018 ◽  
Vol 9 (3) ◽  
pp. 1423
Author(s):  
Aleksey Ishchenko ◽  
Vladimir Shevelev ◽  
Alexander Naronov ◽  
Alexander Tcherepanov ◽  
Boris Shulgin
Keyword(s):  
High Voltage ◽  
Data Transmission ◽  
Signal Transmission ◽  
Power Lines ◽  
Bch Code ◽  
Hamming Code ◽  
Signal Modulation ◽  
Reed Solomon Code ◽  
Modulation Methods ◽  
Communication Lines

<span lang="EN-US">A concept of data transmission within downhole telemetry systems in oilfield industry through power lines is presented. Based on this concept, MATLAB/Simulink models simulating communication lines in downhole telemetry systems are built, which can be used as prototypes for development of real systems. The most appropriate signal modulation methods for data transmission in downhole telemetry systems are suggested and discussed. The influence of high-voltage interference on signal transmission through power line from downhole unit to ground based unit is simulated. Usage of error-correcting coding methods for data transmission such as Hamming code, Reed-Solomon code, BCH code is suggested, and its efficiency is demonstrated.</span>

scholarly journals GPS-Based Indoor/Outdoor Detection Scheme Using Machine Learning Techniques

2020 ◽  
Vol 10 (2) ◽  
pp. 500
Author(s):  
Van Bui ◽  
Nam Tuan Le ◽  
Thanh Luan Vu ◽  
Van Hoa Nguyen ◽  
Yeong Min Jang
Keyword(s):  
Machine Learning ◽  
Signal Transmission ◽  
Outdoor Environment ◽  
Machine Learning Techniques ◽  
Interference Control ◽  
Detection Scheme ◽  
Machine Learning Classification ◽  
Gps Satellites ◽  
Wireless Signal ◽  
Indoor And Outdoor Environments

Recent advances in mobile communication require that indoor/outdoor environment information be available for both individual applications and wireless signal transmission in order to improve interference control and serve upper-layer applications. In this paper, we present a scheme to identify the indoor/outdoor environment using GPS signals combined with machine learning classification techniques. Compared to traditional schemes, which are based on received signal strength indicator (RSSI), the proposed scheme promises a robust approach with high accuracy, smooth operation when moving between indoor and outdoor environments, as well as easy implementation and training. The proposed scheme combined information from a certain number of GPS satellites, using the GPS sensor on mobile devices. Then, data are collected, preprocessed, and classified as indoor or outdoor environment using a machine learning model that is optimized for the best performance. The GPS input data were collected in the Kookmin University area and included 850 training samples and 170 test samples. The overall accuracy reached 97%.

scholarly journals Internal field study of 21700 battery based on long-life embedded wireless temperature sensor

2021 ◽  
Author(s):  
Le Yang ◽  
Na Li ◽  
Likun Hu ◽  
Shaoqi Wang ◽  
Lin Wang ◽  
...  
Keyword(s):  
Integrated Circuit ◽  
Signal Transmission ◽  
Lithium Ion ◽  
Internal Field ◽  
Temperature Sensors ◽  
Temperature Sensing ◽  
Signal Modulation ◽  
Internal Measurement ◽  
Accurate Temperature

AbstractThe safety of lithium-ion batteries is an essential concern where instant and accurate temperature sensing is critical. It is generally desired to put sensors inside batteries for instant sensing. However, the transmission of internal measurement outside batteries without interfering their normal state is a non-trivial task due to the harsh electrochemical environment, the particular packaging structures and the intrinsic electromagnetic shielding problems of batteries. In this work, a novel in-situ temperature sensing framework is proposed by incorporating temperature sensors with a novel signal transmission solution. The signal transmission solution uses a self-designed integrated-circuit which modulates the internal measurements outside battery via its positive pole without package breaking. Extensive experimental results validate the noninterference properties of the proposed framework. Our proposed in-situ temperature measurement by the self-designed signal modulation solution has a promising potential for in-situ battery health monitoring and thus promoting the development of smart batteries. Graphic abstract

scholarly journals User Experience of 7 Mobile Electroencephalography Devices: Comparative Study (Preprint)

2019 ◽  
Author(s):  
Thea Radüntz ◽  
Beate Meffert
Keyword(s):  
User Experience ◽  
Health Informatics ◽  
Technological Development ◽  
Brain Activity ◽  
Signal Transmission ◽  
Signal Acquisition ◽  
Emotional Design ◽  
Visual Appearance ◽  
Wireless Signal ◽  
Significant Change

BACKGROUND Registration of brain activity has become increasingly popular and offers a way to identify the mental state of the user, prevent inappropriate workload, and control other devices by means of brain-computer interfaces. However, electroencephalography (EEG) is often related to user acceptance issues regarding the measuring technique. Meanwhile, emerging mobile EEG technology offers the possibility of gel-free signal acquisition and wireless signal transmission. Nonetheless, user experience research about the new devices is lacking. OBJECTIVE This study aimed to evaluate user experience aspects of emerging mobile EEG devices and, in particular, to investigate wearing comfort and issues related to emotional design. METHODS We considered 7 mobile EEG devices and compared them for their wearing comfort, type of electrodes, visual appearance, and subjects’ preference for daily use. A total of 24 subjects participated in our study and tested every device independently of the others. The devices were selected in a randomized order and worn on consecutive day sessions of 60-min duration. At the end of each session, subjects rated the devices by means of questionnaires. RESULTS Results indicated a highly significant change in maximal possible wearing duration among the EEG devices (χ26=40.2, n=24; P<.001). Regarding the visual perception of devices’ headset design, results indicated a significant change in the subjects’ ratings (χ26=78.7, n=24; P<.001). Results of the subjects’ ratings regarding the practicability of the devices indicated highly significant differences among the EEG devices (χ26=83.2, n=24; P<.001). Ranking order and posthoc tests offered more insight and indicated that pin electrodes had the lowest wearing comfort, in particular, when coupled with a rigid, heavy headset. Finally, multiple linear regression for each device separately revealed that users were not willing to accept less comfort for a more attractive headset design. CONCLUSIONS The study offers a differentiated look at emerging mobile and gel-free EEG technology and the relation between user experience aspects and device preference. Our research could be seen as a precondition for the development of usable applications with wearables and contributes to consumer health informatics and health-enabling technologies. Furthermore, our results provided guidance for the technological development direction of new EEG devices related to the aspects of emotional design.

Sign in / Sign up

Export Citation Format

Share Document