• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.27 no.4
• /
• pp.133-140
• /
• 2004

This study deals with human reaction speed according to human physical conditions (body size) such as head width, thickness, breast width, arm extent, and age. Especially, the results of this study are compared between young and old generation. According to this study, the thickness and extent factor do not have any correlation with human reaction speed, but width factors(head width, breast width, etc) have some correlation with human reaction speed. The result of this study can be used to find fitter person for a special job such as emergency condition job, sports man (because you can find a person having a good talent for it without test). Also, the purpose of this study is to find CNT (Channel Noise Time). The word of CNT is to explain the relation between Channel Noise and working speed. (Channel Noise is a kind of noise happening between the human information transmission channel.)

• Science of Emotion and Sensibility
• /
• v.6 no.2
• /
• pp.9-16
• /
• 2003

This study deals with human reaction speed according to human Physical conditions (head width, breast width, arm extent etc). According to this study, the thickness and extent factor do not affect to human reaction speed, but width factor (head width, breast width). The result of this study can be used to find fitter person for a special job such as emergency condition job, sports man (because you can find a person having a good talent for it before the test). Also, the result of this study can be applied to make CNT (Channel Noise Time) clear The word of CNT is to explain the relation between Channel Noise and Time. (Channel Noise is a kind of noise in the human information transmission channel.).

• ETRI Journal
• /
• v.33 no.2
• /
• pp.176-183
• /
• 2011

This paper presents a new analytical approach and experimental verification for the improvement of noise performance in phased-array receivers. For analysis purposes, a multi-channel array system is converted into an equivalent single-channel system, such that the two presents the identical signal and noise powers at the output, respectively. We define an effective gain, noise figure, and signal-to-noise ratio in the equivalent system. Through the proposed approach, the noise performance of the array receiver is analyzed in a general and straightforward manner and then compared to that of each individual array channel. In addition, the phase noise of the array system is analyzed in a rigorous manner, showing its effective reduction by a factor of the array size. The predicted improvement of the noise performance is experimentally confirmed with a CMOS integrated phased-array receiver.

• Journal of the Semiconductor & Display Technology
• /
• v.12 no.2
• /
• pp.51-56
• /
• 2013

Even if transmissions through normal channel between ubiquitous devices and terminal readers are encrypted, any extra sources of information retrieved from encrypting module can be exploited to figure out the key parameters, so called side channel attack. Since side channel attacks are based on statistical methods, making side channel signal weak or complex is the proper solution to prevent the attack. Among many countermeasures, shielding the electromagnetic signal and adding noise to the EM signal were examined by applying different thicknesses of thin films of ferroelectric (BTO) and conductors (copper and gold). As a test vehicle, chip antenna was utilized to see the change in radiation characteristics: return loss and gain. As a result, the ferroelectric BTO showed no recognizable effect on both shielding and adding noise. Cu thin film showed increasing shielding effect with thickness. Nanometer Au exhibited possibility in adding noise by widening of bandwidth and red shifting of resonating frequencies.

• International Journal of Internet, Broadcasting and Communication
• /
• v.12 no.2
• /
• pp.37-44
• /
• 2020

The fifth generation (5G) mobile communication has been commercialized and the 5G applications, such as the artificial intelligence (AI) and the internet of things (IoT), are deployed all over the world. The 5G new radio (NR) wireless networks are characterized by 100 times more traffic, 1000 times higher system capacity, and 1 ms latency. One of the promising 5G technologies is non-orthogonal multiple access (NOMA). In order for the NOMA performance to be improved, sometimes the additive signal-dependent Gaussian noise (ASDGN) channel model is required. However, the channel capacity calculation of such channels is so difficult, that only lower and upper bounds on the capacity of ASDGN channels have been presented. Such difficulties are due to the specific constraints on the dependency. Herein, we provide the capacity of ASDGN channels, by removing the constraints except the dependency. Then we obtain the ASDGN channel capacity, not lower and upper bounds, so that the clear impact of ASDGN can be clarified, compared to additive white Gaussian noise (AWGN). It is shown that the ASDGN channel capacity is greater than the AWGN channel capacity, for the high signal-to-noise ratio (SNR). We also apply the analytical results to the NOMA scheme to verify the superiority of ASDGN channels.

• Proceedings of the IEEK Conference
• /
• 2001.06a
• /
• pp.37-40
• /
• 2001

Subject of this paper is analysis of channel noise and impedance characteristics for high speed power line communication to concerned noise of transmission line and impedance in the frequency range up to 30MHz. Parameters of transmission line was inducted from experimentally power line channel measurement. Moreover, Analysis of compared based on measurement of channel characters with simulation test for appear characters.

• Journal of Korea Society of Industrial Information Systems
• /
• v.2 no.2
• /
• pp.219-228
• /
• 1997

The Fano metric is the maximum likelihood decoding choice for convlutional code for binary symmetric channel. The Fano metric assumes that it has previous knowledge of channel error probability. However, the bit errors in real channel occur in bursts and the channel error probability can not be known exactly. Thus, the Fano metric is not the maximum likelihood choice for bursty-noise channel. In this paper universal metri which dose not require the previous knowlege of the channel transition probability is used for sequential decoding. It is shown that the complexity of the universal is much less than that of the Fano metric bursty-noise channel, since it is estimated on a branch by branch basis.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.18 no.8
• /
• pp.1136-1145
• /
• 1993

The channel capacities of various lading channels are calculated and compared with that of Gaussian noise channel to find out the decrements of channel capacity according to each fading environment. As a result, it is confirmed that the channel capacities in Rician and m-distribution fading channels approach to that of Gaussian noise channel as direct-to-indirect power ratio in Rician fading channel and fading index m in m-distribution fading channel increases respectively. And the difference between two channel capacities of Gaussian noise channel and each fading channel which is dependent on carrier-to-noise power ratio (CNR) is found. Also the improvement of channel capacity of Rayleigh fading channel by introducing two-branch diversities is obtained. For diversity reception, predetection maximal-ratio and postdetection selective combining techniques are adopted. The results show that the improvement of channel capacity by predetection maximal-ratio combining diversity is superior to the postdetection selective combining diversitiy regardless of correlation coefficient between two diversity branches in Raylelgh fading channel. The best improvement is achieved when two branches are noncorrelative in both two diversify techniques and as correlation coefficient of two diversity branches is smaller, the improvement of channel capacity is greater.

• Proceedings of the KIPE Conference
• /
• 2006.06a
• /
• pp.456-458
• /
• 2006

Power line communication: PLC which easy to install at anywhere near outlet for electric machine. PLC uses transmission line for voltage of which is 60 Hz. Signals don't affect to electric machine in PLC because they are very small voltage. One of the important thing is the processes of adding signal to power line and extracting the signal from power line, the other is to choose the strong modulation method which sends signals long distance without loosing in PLC channel. but PLC channel have very high and variable noise and attenuation and then it is very hard to transmit optimally between the transmitter and the receiver. After all, impedance and noise problems of PLC channel must be overcame. Noises of 2 kinds which are AWGN abd impulse noise and attenuation are orated. To overcome the noise. Recently, Multi-carrier Modulation: MCM methods like as OFDM and DMT which are divide the channel into many sub-channel have been studied. those are powerful communication methods in PLC. In this paper, PLC channels made up of 3 numbers of noise and attenuation are simulated for getting BER by Matlab simulink.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.12 no.8
• /
• pp.3589-3605
• /
• 2018

In this paper, we investigate an individual channel estimation problem for multiple-input multiple-output (MIMO) two-way amplify-and-forward (AF) relay networks. To avoid self-interference during the estimation of the individual MIMO channels, a novel blind interference cancellation (BIC) approach is proposed based on an orthogonal preceding framework, where a pair of orthogonal precoding matrices is utilized at the source nodes. By designing an optimal decoding scheme, we propose to decompose the bidirectional transmission into a pair of unidirectional transmissions. Unlike most existing approaches, we make the practical assumption that the nonreciprocal MIMO channel and the mutual interference of multiple antennas are both taken into consideration. Under the precoding framework, we employ an orthogonal superimposed training strategy to obtain the individual MIMO channels. However, the AF strategy causes the noise at the terminal to be the sum of the local noise and the relay-propagated noise. To remove the relay-propagated noise during the estimation of the second-hop channel, a partial noise-nulling method is designed. We also derive a closed-form expression for the total mean square error (MSE) of the MIMO channel from which we compute the optimal power allocation. The simulation results demonstrate that the analytical and simulated curves match fully.