• Korean Journal of Mathematics
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• v.17 no.4
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• pp.399-409
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• 2009

We study the weak convergence of various models to Fractional Brownian motion. First, we consider arima process and ON/OFF source model which allows for long packet trains and long inter-train distances. Finally, we figure out power spectrum density as a Fourier transform of autocorrelation function of arima model and binary signal model.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.15 no.5
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• pp.486-492
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• 2004

In this paper, we newly propose the binary CA-CDMA(constant amplitude CDMA) system using pre-coding method to solve the high PAPR problem caused by multi-user signal transmission in the CDMA system. 4-user CA-CDMA, the basis of proposed binary CA-CDMA system, makes binary output signal for 4 input users. It produces the output of binary(${\pm}$2) amplitude by using a parity signal resulting from the XOR operation of 4 users data. Another sub-channel or more bandwidth is not necessary because it is transmitted together with user data and can be easily recovered in the receiver. The extension of the number of users can be possible by the simple repetition of the basic binary 4-user CA-CDMA. For example, binary 16-user CA-CDMA is made easily by allocating the four 4-user CA-CDMA systems in parallel and leading the four outputs to the fifth 4-user CA-CDMA system as input, because the output signal of each 4-user CA-CDMA is also binary. By the same extension procedure, binary 64 and 256-user CA-CDMA systems can be made with the constant amplitude. As a result, the code rate of this proposed CA-CDMA system is just 1 and binary CA-CDMA does not change the transmission rate with the constant output signal(PAPR = 0 ㏈). Therefore, the power efficiency of the HPA can be maximized without the nonlinear distortion. From the simulation results, it is verified that the conventional CDMA system has multi-level output signal, but the proposed binary CA-CDMA system always produces binary output. And it is also found that the BER of conventional CDMA system is increased by nonlinear HPA, but the BER of proposed binary CA-CDMA system is not changed.

• Transactions of the Society of Information Storage Systems
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• v.1 no.1
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• pp.53-57
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• 2005

In order to measure signal quality of optical disc such as CD or DVD, jitter is used traditionally. The signal attained from a disc by optical pick-up is processed by analog circuits. And then, binary signal can be obtained by using proper silcer. After the signal is changed into binary format, jitter is calculated as a time difference between the binary signal and the reference time. Jitter is used to express the signal quality. In this paper, a new method that is able to offer more precise measurement of the signal quality fur high density optical disc than the jitter is proposed. We named it LPSNR (Level Peak Signal to Noise Ratio). The relationship between bER (bit error rate) and LPSNR is shown in the paper.

• IEIE Transactions on Smart Processing and Computing
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• v.2 no.4
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• pp.197-202
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• 2013

Large gains in speech intelligibility can be obtained using the SNR-based binary mask approach. This approach retains the time-frequency (T-F) units of the mixture signal, where the target signal is stronger than the interference noise (masker) (e.g., SNR > 0 dB), and removes the T-F units, where the interfering noise is dominant. This paper introduces two alternative binary masks based on the distortion constraints to improve the speech intelligibility. The distortion constraints are induced by a gain function for estimating the short-time spectral amplitude. One binary mask is designed to retain the speech underestimated (T-F) units while removing the speech overestimated (T-F)units. The other binary mask is designed to retain the noise overestimated (T-F) units while removing noise underestimated (T-F) units. Listening tests with oracle binary masks were conducted to assess the potential of the two binary masks in improving the intelligibility. The results suggested that the two binary masks based on distortion constraints can provide large gains in intelligibility when applied to noise-corrupted speech.

• Journal of Sensor Science and Technology
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• v.30 no.2
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• pp.82-87
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• 2021

In this paper, we propose a high-speed, low-power complementary metal-oxide semiconductor (CMOS) binary image sensor featuring a gate/body-tied (GBT) p-channel metal-oxide-semiconductor field-effect transistor (PMOSFET)-type photodetector based on a double-tail comparator. The GBT photodetector forms a structure in which the floating gate (n+ polysilicon) and body of the PMOSFET are tied, and amplifies the photocurrent generated by incident light. The double-tail comparator compares the output signal of a pixel against a reference voltage and returns a binary signal, and it exhibits improved power consumption and processing speed compared with those of a conventional two-stage comparator. The proposed sensor has the advantages of a high signal processing speed and low power consumption. The proposed CMOS binary image sensor was designed and fabricated using a standard 0.18 ㎛ CMOS process.

• Journal of Sensor Science and Technology
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• v.29 no.2
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• pp.82-88
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• 2020

In this paper, we propose a complementary metal-oxide semiconductor (CMOS) binary image sensor with a gate/body-tied (GBT) p-channel metal-oxide-semiconductor field-effect transistor (PMOSFET)-type photodetector using a double-tail comparator for high-speed and low-power operations. The GBT photodetector is based on a PMOSFET tied with a floating gate (n+ polysilicon) and a body that amplifies the photocurrent generated by incident light. A double-tail comparator compares an input signal with a reference voltage and returns the output signal as either 0 or 1. The signal processing speed and power consumption of a double-tail comparator are superior over those of conventional comparator. Further, the use of a double-sampling circuit reduces the standard deviation of the output voltages. Therefore, the proposed CMOS binary image sensor using a double-tail comparator might have advantages, such as low power consumption and high signal processing speed. The proposed CMOS binary image sensor is designed and simulated using the standard 0.18 ㎛ CMOS process.

• Journal of the Korean Institute of Telematics and Electronics
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• v.23 no.5
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• pp.591-596
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• 1986

A binary continuous phase frequency shift keying (CPFSK), whose phase is a continuous function of time and instantaneous frequency is constant, is a bandwidth efficient constant envelope signalling scheme. A transmitting signal is formed by combined coding of a convolutional encoder and a binary CPFSK modulator. The signal is transmitted throuth additive white Gaussian noise(AWGN) channel. If the received signal is detected by a coherent maximum likelihood(ML) receiver, error probability can be expressed approximately in terms of minimum Euclidean distance. We propose rate 2/4 codes for the improvement of error performance without increating the data rate per bandwidth and the receiver complexity. Its minimum Euclidean distances are compared with those of rate \ulcornercodes as a function of modulation index and observation interval.

• 전기의세계
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• v.19 no.6
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• pp.1-7
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• 1970

In this paper, to determine process dynamic characteristics, the correlation method for measuring the impulse response of process using a pseudo-random binary signal as the test signal instead of white noise was studied. The error caused by using the signal of Mesquence signal generator which was built up by the authors was analysed. Experments were performed on the 1st and 2nd order lag systems and the results were in good coincidence with theoretical values. It is expected that applying these results, it may be possible to develop a continuous measuring method adaptable to modern control systems.

• ETRI Journal
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• v.36 no.5
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• pp.772-782
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• 2014

Two-microphone binary mask speech enhancement (2mBMSE) has been of particular interest in recent literature and has shown promising results. Current 2mBMSE systems rely on spatial cues of speech and noise sources. Although these cues are helpful for directional noise sources, they lose their efficiency in diffuse noise fields. We propose a new system that is effective in both directional and diffuse noise conditions. The system exploits two features. The first determines whether a given time-frequency (T-F) unit of the input spectrum is dominated by a diffuse or directional source. A diffuse signal is certainly a noise signal, but a directional signal could correspond to a noise or speech source. The second feature discriminates between T-F units dominated by speech or directional noise signals. Speech enhancement is performed using a binary mask, calculated based on the proposed features. In both directional and diffuse noise fields, the proposed system segregates speech T-F units with hit rates above 85%. It outperforms previous solutions in terms of signal-to-noise ratio and perceptual evaluation of speech quality improvement, especially in diffuse noise conditions.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38A no.6
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• pp.512-519
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• 2013

In this paper, we propose a novel unambiguous correlation function for composite binary offset carrier (CBOC) signal tracking. First, we observe that a sub-carrier of CBOC signal is seen as a sum of four partial sub-carriers, and generate four partial-correlations composing the CBOC autocorrelation. Then, we obtain an unambiguous correlation function with a sharp main-peak by re-combining the partial correlations. From numerical results, we confirm that the proposed unambiguous correlation function offers a better tracking performance than the conventional correlation functions in terms of the tracking error standard deviation and multipath error envelope.