scholarly journals Combined Detector with Retraining Data Sequence

2018 ◽  
Vol 15 (1) ◽  
pp. 47-50
Author(s):  
Muhanned AL-Rawi ◽  
Muaayed AL-Rawi

Abstract Two detectors are presented in this paper which are used to handle intersymbol interference introduced by the communication channels. These two detectors are based on combination of nonlinear equalizer and Viterbi detector. The first detector, which was previously developed, is named Combined Detector1(CDR1), while, the second detector, which is the contribution of this paper, is named Combined Detector-2(CDR2). CDR2 is similar to CDR1 but with retraining data sequence. These detectors are tested beside nonlinear equalizer using data transmission at 9.6kb/s over telephone channel. Simulation results show that the performance of CDR2 is better than the performance of CDR1 while the performance of CDR1 is better than the performance of nonlinear equalizer.

2018 ◽  
Vol 15 (2) ◽  
pp. 27-30
Author(s):  
Muhanned AL-Rawi

Abstract This paper presents new modified QAM modem that operates at data rate of 14.4kb/s to be transmitted over 32kb/s Adaptive Differential Pulse Code Modulation (ADPCM). The purpose of this modified QAM modem is to reduce the nonlinear distortion introduced by ADPCM. The performance of ADPCM is studied considering the standard QAM modem and modified QAM modem with different constellations. The simulation results show that the performance of ADPCM with modified QAM modem is better than its performance with standard QAM modem. Also, the performance with circular constellation is better than rectangular one.


2019 ◽  
Vol 888 ◽  
pp. 59-65 ◽  
Author(s):  
Yosuke Iijima ◽  
Yasushi Yuminaka

This paper presents an evaluation of double-rate Tomlinson-Harashima precoding in multi-valued PAM-N data transmission. In order to eliminate an intersymbol interference of interconnections in VLS system, Tomlinson-Harashima precoding (THP) is very useful for limiting the peak and average power of the transmitter. To expand the eye-opening at a receiver in multi-valued data transmission, we proposed a new equalization technique by using double-rate THP. In this paper, to evaluate the performance of the double-rate THP, we show the simulation results of the double-rate THP in various PAM-N data transmission on a micro-strip line.


2018 ◽  
Vol 7 (4.19) ◽  
pp. 1072
Author(s):  
Basanti Ghanti ◽  
Rajendra R Patil

The work presented considers a Physical Layer Network Coded (PNC) communication which is affected by Intersymbol Interference (ISI) due to Rayleigh fading channel. A pre-equalizer filter configured to combat the ISI is considered at the end nodes. The relay uses the Amplify and Forward (AF) strategy. The signal in the Multiple Access (MAC) phase is amplified at the relay and forwarded to the receiving nodes. The signal received by the end nodes in the broadcast (BC) phase is subjected to post-equalization by a receiver filter configured to overcome ISI. The performance of the PNC with only pre-equalizer applied, only post-equalization applied and the combined effect of pre-equalizer and post-equalizer is simulated .Simulation results indicate that the performance of PNC when only pre-equalizer applied , only post-equalization is applied are not much varying but better than the no equalization case. But the combined effect of pre-and post-equalization is much improved.  


Sensors ◽  
2020 ◽  
Vol 20 (16) ◽  
pp. 4419
Author(s):  
Ting Li ◽  
Haiping Shang ◽  
Weibing Wang

A pressure sensor in the range of 0–120 MPa with a square diaphragm was designed and fabricated, which was isolated by the oil-filled package. The nonlinearity of the device without circuit compensation is better than 0.4%, and the accuracy is 0.43%. This sensor model was simulated by ANSYS software. Based on this model, we simulated the output voltage and nonlinearity when piezoresistors locations change. The simulation results showed that as the stress of the longitudinal resistor (RL) was increased compared to the transverse resistor (RT), the nonlinear error of the pressure sensor would first decrease to about 0 and then increase. The theoretical calculation and mathematical fitting were given to this phenomenon. Based on this discovery, a method for optimizing the nonlinearity of high-pressure sensors while ensuring the maximum sensitivity was proposed. In the simulation, the output of the optimized model had a significant improvement over the original model, and the nonlinear error significantly decreased from 0.106% to 0.0000713%.


2021 ◽  
Vol 13 (4) ◽  
pp. 168781402110112
Author(s):  
Yan Lou ◽  
Kewei Chen ◽  
Xiangwei Zhou ◽  
Yanfeng Feng

A novel Injection-rolling Nozzle (IRN) in an imprint system with continuous injection direct rolling (CIDR) for ultra-thin microstructure polymer guide light plates was developed to achieve uniform flow velocity and temperature at the width direction of the cavity exit. A novel IRN cavity was designed. There are eight of feature parameters of cavity were optimized by orthogonal experiments and numerical simulation. Results show that the flow velocity at the width direction of the IRN outlet can reach uniformity, which is far better than that of traditional cavity. The smallest flow velocity difference and temperature difference was 0.6 mm/s and 0.24 K, respectively. The superior performance of the IRN was verified through a CIDR experiment. Several 0.35-mm thick, 340-mm wide, and 10-m long microstructural Polymethyl Methacrylate (PMMA) guide light plates were manufactured. The average filling rates of the microgrooves with the aspect ratio 1:3 reached above 93%. The average light transmittance is 88%.


2011 ◽  
Vol 497 ◽  
pp. 296-305
Author(s):  
Yasushi Yuminaka ◽  
Kyohei Kawano

In this paper, we present a bandwidth-efficient partial-response signaling scheme for capacitivelycoupled chip-to-chip data transmission to increase data rate. Partial-response coding is knownas a technique that allows high-speed transmission while using a limited frequency bandwidth, by allowingcontrolled intersymbol interference (ISI). Analysis and circuit simulation results are presentedto show the impact of duobinary (1+D) and dicode (1-D) partial-response signaling for capacitivelycoupled interface.


2003 ◽  
Vol 56 (2) ◽  
pp. 323-335 ◽  
Author(s):  
Paul D. Groves

Transfer alignment is the process of initialising and calibrating a weapon INS using data from the host aircraft's navigation system. To determine which transfer alignment technique performs best, different design options have been assessed, supported by simulation work. The dependence of transfer alignment performance on environmental factors, such as manoeuvres, alignment duration, lever arm and inertial sensor quality has also been studied. ‘Rapid’ alignment, using attitude as well as velocity measurements was found to perform better than ‘conventional’ techniques using only velocity. Innovative developments include the estimation of additional acceleration and gyro states and estimation of force dependent relative orientation, which has enabled robust alignment using wing rock manoeuvres, which do not require the pilot to change trajectory. Transfer alignment has been verified in real-time by flight trials on a Tornado aircraft. In addition, techniques have been developed to prevent transients in the aircraft integrated navigation solution following GPS re-acquisition after an outage of several minutes from disrupting the transfer alignment process.


2011 ◽  
Vol 474-476 ◽  
pp. 828-833
Author(s):  
Wen Jun Xu ◽  
Li Juan Sun ◽  
Jian Guo ◽  
Ru Chuan Wang

In order to reduce the average path length of the wireless sensor networks (WSNs) and save the energy, in this paper, the concept of the small world is introduced into the routing designs of WSNs. So a new small world routing protocol (SWRP) is proposed. By adding a few short cut links, which are confined to a fraction of the network diameter, we construct a small world network. Then the protocol finds paths through recurrent propagations of weak and strong links. The simulation results indicate that SWRP reduces the energy consumption effectively and the average delay of the data transmission, which leads to prolong the lifetime of both the nodes and the network.


2012 ◽  
Vol 501 ◽  
pp. 151-155
Author(s):  
Yong Liu ◽  
Ge Zhang ◽  
Hua Yan ◽  
Yu Mei Ding ◽  
Wei Min Yang

In this article, three kinds of belt named B, C and D type are invented, then their main performance are compared with the other two kinds of belt structures introduced in previous papers. Simulation results showed that B and D-type belts are better than the other three. Comparatively the latter needs less material, its molding process is easier, and the tire body is lighter than B type tire, so in general it can be considered that D-type belt is the best among the five kinds of belt structures.


2013 ◽  
Vol 330 ◽  
pp. 957-960
Author(s):  
Qiao Ling Du ◽  
Zhi Rui Wang ◽  
Yu Pei ◽  
Yi Ding Wang

This paper investigates the performance analysis of OQPSK in HF band for wireless sensor networks. An analytical model for getting symbol error rate (SER) is given in presence of Bi-Kappa noise in HF band. And the SER of OQPSK is given in AWGN and Rayleigh fading channel. Simulation results HF noise as Bi-Kappa noise should be investigated in HF band for WSN.


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