A Novel Method for Pulse Integration in Radar-Probing System

2012 ◽  
Vol 529 ◽  
pp. 23-28
Author(s):  
Ya Ming Xi ◽  
Rong Jiu Huang ◽  
Yan Jing Han ◽  
Qing Zhang
Keyword(s):  
Spread Spectrum ◽  
Cross Correlation ◽  
Pulse Sequence ◽  
Side Lobe ◽  
Bipolar Pulse ◽  
System A ◽  
Low Sidelobe ◽  
M Sequence ◽  
Novel Method ◽  
Correlation Properties

In this paper, a novel method for pulse integration in radar-probing system is proposed to yield a low sidelobe response. According to m-sequence widely used in spread spectrum communication system, a bipolar pulse sequence is designed in this paper. At the receiving end, the envelop-detected signal is processed by a corresponding algorithm which dilutes the range sidelobe influence much. Because of the good autocorrelation and cross-correlation properties, waveforms yield a low sidelobe response and major lobe to side lobe ratio can reach 30dB or more, which is easy to satisfy the practical requirements. Simulation results show the good performance of the proposed approach. Furthermore, the approach is compatible to the conventional radars and can also be applied to the upgrade of radar.

Netted Radar System Design with Spread Spectrum Technology

2011 ◽  
Vol 55-57 ◽  
pp. 648-653
Author(s):  
Lian Qing Fu ◽  
Li Sheng Yang ◽  
Tao Wang ◽  
Qing Le Zhang
Keyword(s):  
System Design ◽  
Spread Spectrum ◽  
Cross Correlation ◽  
Mutual Interference ◽  
Radar System ◽  
Power Ratio ◽  
Emission Signal ◽  
Simulation Results ◽  
Correlation Properties

In this paper, a novel netted radar system is designed to reduce the influence of mutual interference between signals. The emission signals of all stations are assigned the orthogonal PN codes. Because of the good autocorrelation and cross-correlation properties, mutual interference becomes weaker and signals from different stations could be separated by the preassigned PN codes. At the same time, the spectrum of the emission signal is spreaded, the peak-to-mean envelope power ratio (PMEPR) and the intercepted probability of the signals descend therefore. Simulation results show the good performance of the proposed approach.

Frequency Hopping Sequences with Given Minimum Gap Based on M-Sequence

2011 ◽  
Vol 225-226 ◽  
pp. 47-50
Author(s):  
Ye Xu ◽  
Hong Yan
Keyword(s):  
Cross Correlation ◽  
Frequency Hopping ◽  
Simulation Experiments ◽  
Auto Correlation ◽  
M Sequence ◽  
Frequency Hopping Sequences ◽  
Correlation Properties

Based on optimal families of FH sequences derived from m-sequence over GF(p), a construction of families of FH sequences with given minimum gap is presented to overcome the shortcoming of dual sub-bands method. The Hamming auto-correlation and cross-correlation properties of the FH sequences are theoretically studied and simulation experiments are performed. Results show that the correlation properties of these FH sequences are acceptable.

Comparative Study on Spreading Codes

2017 ◽  
Vol MCSP2017 (01) ◽  
pp. 14-16
Author(s):  
Omprava Agasti ◽  
Sujatarani Raut ◽  
Shibashis Pradhan
Keyword(s):  
Communication Networks ◽  
Spread Spectrum ◽  
Cross Correlation ◽  
Additive White Gaussian Noise ◽  
Personal Communication ◽  
Spreading Codes ◽  
Personal Communication Networks ◽  
Transmission Data ◽  
Commercial Applications ◽  
Spread Spectrum Systems

In this paper, we studied on spreading code for wireless communication, their performance analysis, applications and its implementation. Spread-spectrum systems have found important commercial applications in CDMA cellular networks and wireless personal communication networks. Implementation is complex, mainly because spreading the baseband (by a factor that can be several orders of magnitude) forces the electronics to act and react accordingly, which, in turn, makes the spreading and dispreading operation necessary. In spread spectrum the transmission signal bandwidth is much higher than the information bandwidth. The signal occupies a bandwidth much larger than what is necessary to send the information in spread spectrum technology. CDMA uses unique spreading codes to spread the baseband data before transmission data. The performance of a CDMA system gets controlled by two types of interference, namely ISI and MAI which are the function of auto and cross correlation values of the spreading codes respectively. The existing codes using Additive White Gaussian Noise channel under multi-user has been compared with the Bit Error Rate(BER) performance.

scholarly journals Decentralized Optimization for a Novel Control Structure of HVAC System

2016 ◽  
Vol 2016 ◽  
pp. 1-13 ◽  
Author(s):  
Shiqiang Wang ◽  
Jianchun Xing ◽  
Ziyan Jiang ◽  
Juelong Li
Keyword(s):  
Control System ◽  
Decentralized Control ◽  
Control Structure ◽  
Optimization Method ◽  
Labor Cost ◽  
Smart Device ◽  
Hvac System ◽  
Decentralized Optimization ◽  
System A ◽  
Novel Method

A decentralized control structure is introduced into the heating, ventilation, and air conditioning (HVAC) system to solve the high maintenance and labor cost problem in actual engineering. Based on this new control system, a decentralized optimization method is presented for sensor fault repair and optimal group control of HVAC equipment. Convergence property of the novel method is theoretically analyzed considering both convex and nonconvex systems with constraints. In this decentralized control system, traditional device is fitted with a control chip such that it becomes a smart device. The smart device can communicate and operate collaboratively with the other devices to accomplish some designated tasks. The effectiveness of the presented method is verified by simulations and hardware tests.

DETERMINING ROBUST PARAMETERS IN STABILIZING SET OF BACKSTEPPING BASED NONLINEAR CONTROLLER FOR SHIP COURSE KEEPING

2021 ◽  
Vol 158 (A3) ◽  
Author(s):  
X K Zhang ◽  
G Q Zhang
Keyword(s):  
Closed Loop ◽  
Simulation Experiment ◽  
Empirical Knowledge ◽  
Backstepping Method ◽  
Nonlinear Controller ◽  
Closed Loop System ◽  
Robust Performance ◽  
System A ◽  
Uniformly Asymptotic Stability ◽  
Novel Method

In order to solve the problem that backstepping method cannot effectively guarantee the robust performance of the closed-loop system, a novel method of determining parameter is developed in this note. Based on the ship manoeuvring empirical knowledge and the closed-loop shaping theory, the derived parameters belong to a reduced robust group in the original stabilizing set. The uniformly asymptotic stability is achieved theoretically. The training vessel “Yulong” and the tanker “Daqing232” are selected as the plants in the simulation experiment. And the simulation results are presented to demonstrate the effectiveness of the proposed algorithm.

scholarly journals New Orthogonal Small Set Kasami Code Sequence

2015 ◽  
Vol 14 (1) ◽  
Author(s):  
I Nyoman Pramaita ◽  
I G.A.G.K. Diafari ◽  
DNKP Negara ◽  
Agus Dharma
Keyword(s):  
Correlation Function ◽  
Cross Correlation ◽  
Code Sequence ◽  
Cross Correlation Function ◽  
Auto Correlation ◽  
M Sequence ◽  
Auto Correlation Function ◽  
Small Set

In this paper, the authors propose the design of a new orthogonal small set Kasami code sequence generated using combination of non-orthogonal m-sequence and small set Kasami code sequence. The authors demonstrate that the proposed code sequence has comparable auto-correlation function (ACF), cross- correlation function (CCF), peak cross-correlation values with that of the existing orthogonal small set Kasami code sequence. Though the proposed code sequence has less code sequence sets than that of the existing orthogonal small set Kasami code sequence, the proposed code sequence possesses one more numbers of members in each code sequence set. The members of the same code set of the proposed code sequence are orthogonal to each other.

Flow Control by Pulso Width Modulation

1972 ◽  
Vol 5 (4) ◽  
pp. 142-146
Author(s):  
M S Beck ◽  
N E Gough ◽  
J N Smithies
Keyword(s):  
Cross Correlation ◽  
Pulse Width Modulation ◽  
Correlation Method ◽  
Temperature Fluctuations ◽  
Flow Rates ◽  
Start Up ◽  
On Line ◽  
Measured Flow ◽  
Novel Method ◽  
Modulation Control

A novel method of controlling the flow rates of fluids has been devised which is particularly suitable for highly erosive fluids and slurries. The width of pulses in a pulse train actuating an on-off valve is modulated according to the error between the desired and measured flow rates and thus the ratio of the total times the valve spends in its ‘on’ and ‘off’ states is varied. The method has been tested with an on-line computer which was used to measure the flow rate of water by a cross-correlation method to determine the transit time of temperature fluctuations between two thermocouples in the pipe, and to implement the pulse width modulation control. Satisfactory results have been obtained for start-up, set-point changes and load disturbances for flow rates in the turbulent region (Re > 3 600). Future development includes the use of a fluidic diverter as the on-off device.

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