noise immunity
Recently Published Documents


TOTAL DOCUMENTS

661
(FIVE YEARS 255)

H-INDEX

15
(FIVE YEARS 3)

Author(s):  
Andriy Dudnik ◽  
◽  
Ivan Bakhov ◽  
Oleksandr Makhovych ◽  
Yulia Ryabokin ◽  
...  

The paper discusses models and methods for improving the performance of wireless computer networks built based on the decomposition of the lower levels of the OSI reference model. A method to improve the performance of networks is suggested, which functionally combines the physical and network layers, which improves its efficiency in marginal reception areas almost twice. A model of the block diagram of a device for improving data transmission quality in marginal reception areas or those with insufficient noise immunity is developed based on the so-called communication quality status monitoring, as well as a model of the block diagram of a wireless adaptive capacity reallocation router based on dynamic channels capacity reallocation, which allows adequately reallocating IS resources depending on traffic and user priority. Keywords— Bluetooth, FIFO discipline, IEEE 802.11, OSI/ISO reference model, wireless computer networks.


Author(s):  
Soumyashee Soumyaprakash Panda ◽  
Ravi Hegde

Abstract Free-space diffractive optical networks are a class of trainable optical media that are currently being explored as a novel hardware platform for neural engines. The training phase of such systems is usually performed in a computer and the learned weights are then transferred onto optical hardware ("ex-situ training"). Although this process of weight transfer has many practical advantages, it is often accompanied by performance degrading faults in the fabricated hardware. Being analog systems, these engines are also subject to performance degradation due to noises in the inputs and during optoelectronic conversion. Considering diffractive optical networks (DON) trained for image classification tasks on standard datasets, we numerically study the performance degradation arising out of weight faults and injected noises and methods to ameliorate these effects. Training regimens based on intentional fault and noise injection during the training phase are only found marginally successful at imparting fault tolerance or noise immunity. We propose an alternative training regimen using gradient based regularization terms in the training objective that are found to impart some degree of fault tolerance and noise immunity in comparison to injection based training regimen.


2022 ◽  
Vol 355 ◽  
pp. 03013
Author(s):  
Xianghui Zhang ◽  
Zhanjiang Yu ◽  
Jinkai Xu ◽  
Huadong Yu

According to the characteristics of micro parts microscopic detection image, including the image texture is similar, the edge information is too little and the gray distribution Range is limited, based on the basic principles of algorithm, analyzes the traditional sharpness evaluation function. Aiming at the defect that the traditional sharpness evaluation function cannot have both high sensitivity and noise immunity, an algorithm based on local variance information entropy is proposed. The method uses the local variance to weight the self-information of each gray level, on the one hand, it makes up for the lack of spatial information of information entropy and avoids misjudgement of sharpness; on the other hand, it can increase the weights of clear region pixels when they participate in the calculation of information, while reducing the weights of background and noise region pixels, thereby improve the function sensitivity. The experimental results show that compared with the traditional sharpness evaluation function, the local variance information entropy function not only has high sensitivity, but also has better noise immunity and is suitable for actual auto-focusing systems.


Electronics ◽  
2021 ◽  
Vol 10 (24) ◽  
pp. 3168
Author(s):  
Yao-Hua Xu ◽  
Shuai Yang ◽  
Hang Li ◽  
Ji-Ming Lv ◽  
Na Bai

This paper presents a new signal demodulator for ultra-high frequency (UHF) radio frequency identification (RFID) tag chips. The demodulator is used to demodulate amplitude shift keying (ASK) modulated signals with the advantages of high noise immunity, large input range and low power consumption. The demodulator consists of a charge pump, an envelope detector, and a comparator. In particular, the demodulator provides a hysteresis input signal to the comparator through two envelope detectors, resulting in better noise immunity. The demodulator is based on a standard 0.13 µm CMOS process. The demodulator is suitable for demodulating high frequency signals at 900 MHz with a data rate of 128 Kbps and can operate up to 78 °C. The input signal has a peak of 1.2 V and consumes as little as 113.6 nW. The demodulator also has a noise immunity threshold of approximately 3.729 V.


Author(s):  
G. V. Kulikov ◽  
Trung Tien Do ◽  
E. V. Samokhina

Objectives. The widespread use of radio data transmission systems using signals with multiposition phase shift keying (MPSK) is due to their high noise immunity and the simplicity of constructing the transmitting and receiving parts of the equipment. The conducted studies have shown that the presence of non-fluctuation interference, in particular, harmonic interference, in the radio channel significantly reduces the noise immunity of receiving discrete information. The energy loss in this case, depending on the interference intensity, can range from fractions of dB to 10 db or more. Therefore, interference suppression is an important task for such radio systems. The aim of the work is to synthesize and analyze an algorithm for optimal nonlinear filtering of MPSK signals against a background of harmonic interference with a random initial phase.Methods. The provisions of the theory of optimal nonlinear signal filtering and methods of statistical radio engineering are used.Results. The synthesis and analysis of the algorithm of optimal nonlinear filtering of MPSK signals against the background of harmonic interference with a random initial phase are carried out. The synthesized receiver contains a discrete symbol evaluation unit, two phase-locked frequency circuits of reference generators that form evaluation copies of the signal and interference, and cross-links between them. Analytical expressions are obtained that allow calculating the dependences of the bit error probability on the signal-to-noise ratio and the interference intensity µ. It is established that uncompensated fluctuations of the initial phase of the useful signal have a greater effect on the receiver noise immunity than similar fluctuations of the phase of harmonic interference, especially with low positional signals.Conclusions. Comparison of the obtained results with the results obtained in the case when there are no harmonic interference compensation circuits shows that the use of the obtained phase filtering algorithms allows for almost complete suppression of harmonic interference. Thus, if µ = 0.5 and the probability of error is 10−2, the energy gain at M = 2 is about 2.5 dB, at M = 4 – about 6 dB, at M = 8 and M = 16 – at least 10 dB.


2021 ◽  
pp. 277-290
Author(s):  
B. R. Kangozhin ◽  
O. A. Baimuratov ◽  
M. S. Zharmagambetova ◽  
S. S. Dautov ◽  
D. B. Kangozhin

2021 ◽  
Vol 3 (2) ◽  
pp. 45-50
Author(s):  
I. G. Tsmots ◽  
◽  
O. Ya. Riznyk ◽  
B. I. Balych ◽  
Ch. Z. Lvovskij ◽  
...  

Noise immunity is one of the essential characteristics of modern wireless data reception/transmission systems. In wireless systems such as Wi-Fi, HiperLan, or Bluetooth, the signal is propagated by electromagnetic oscillations in the environment. However, unlike wiring systems, these oscillations are unprotected from external influences. Noise immunity is one of the essential characteristics of modern wireless data reception/transmission systems. Moreover, if several wireless systems work close enough to each other, there is a possibility of overlapping waves, which will damage the information signal. It is determined that for the tasks of control of unmanned aerial vehicles and mobile robotic complexes increasing the noise immunity of data transmission channels is an urgent problem. It has been investigated that Barker-like code sequences based on ideal ring bundles provide an increase in the power of the obtained sequences by optimizing the parameters of the ideal ring bundles used. It is determined that the increase of noise immunity during data reception and transmission is achieved by choosing the optimal ratios of the parameters of the ideal ring bundle. It is shown that the advantages of Barker-like code sequences such as the optimal ratio between the length of the sequence and its correcting ability, the ability to change the length of the sequence depending on the level of interference are widely used in modern wireless communication and telecommunications systems. The method of synthesis of Barker-like code sequences with the use of ideal ring bundles has been improved, which, by taking into account the ratios of the parameters of ideal ring bundles, provides the choice of the minimum bit code sequence that takes into account the level of interference. A simulation model of synthesis of Barker-like code sequences, noise generation, and error correction has been developed on the basis of the improved method of synthesis of Barker-like code sequences. The developed simulation model is used to study the processes of coding, decoding, detection, and correction of errors in the obtained Barker-like code sequences. It has been investigated that the use of synthesized Barker-like code sequences based on ideal ring bundles provides data recovery of damaged no more than 25 % of the bits of each codeword, and detects up to 50 % of damaged bits in each codeword. Keywords: Barker-like code sequence; ideal ring bundle; noise-tolerant coding; simulation model.


2021 ◽  
Author(s):  
Anatoliy I. Falko ◽  
Maxim S. Shushnov ◽  
Tatiana V. Shushnova ◽  
Anna S. Belezekova
Keyword(s):  

Sign in / Sign up

Export Citation Format

Share Document