• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.3C
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• pp.295-301
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• 2010

In this paper, we propose a new mouthpiece model for the electronic wind instrument using a propeller and linear analysis for fast tracking wind velocity blown. This method is a modification of the velocity anemometer for fast tracking wind velocity by the propeller's angular velocity (speed of revolution). In the case of velocity anemometer, wind velocity is calculated using the property that wind velocity is in proportion to the propeller's angular velocity. However, wind velocity and angular velocity of the propeller are not in one-one correspondence because wind velocity takes some transitional time for the expected wind velocity to be calculated from angular velocity. To resolve this problem, we propose a method for finding the impulse response of the system which can be considered as a linear system, and for estimating the wind velocity by deconvolving the propeller's angular velocity with the impulse response. To experiment and to prove the validity of the proposed system, we designed a mouthpiece model which consists of a motor, a propeller and an encoder. The result of estimated wind velocity in this method showed that this system is about eightfold faster than the method by the conventional velocity anemometer.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.6A
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• pp.537-543
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• 2007

In this paper, we propose a new stopping criterion for the turbo processing (Turbo-BLAST) of MIMO-OFDM system. To reduce the high computational complexity of turbo-BLAST, it is desirable to lessen the outer-loop iteration number. In a system such as IEEE 802.16e Mobile WiMax, no CRC bits are available except the last encoding packet of a transmitted burst, so early stopping criteria without the help of CRC bits are needed. The proposed criterion counts the sign differences between received parity bits and the re-encoded parity bits from received information bits. With the tail-biting code which is accepted for IEEE 802.16e, a method that the re-encoder operates at half complexity is also proposed. Computer simulations show that the proposed stopping criterion approaches the performance of GENIE aided criterion with less average number of iterations than the other early stopping criteria.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.2
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• pp.383-393
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• 2010

DVC (Distributed Video Coding) allows us to explore the video statistics at the decoder side, resulting in a less complex encoder and more complex decoder. In this approach, it is important to generate a good prediction to the current Wyner-Ziv frame, called side information, which plays a crucial role in the overall performance of a DVC system. Conventional MCFI (motion compensated frame interpolation) techniques, which explore temporal correlations between neighbor frames of the current frame, preform the block-based or object-based motion estimation, but, they do not include the basis frame for the Wyner-Ziv frame. This paper proposes an efficient way to get better side information, by finding the average frame between neighbor frames and by comparing adaptively the candidate blocks. Through computer simulations, it is shown that the proposed method can improve the performance up to 0.4dB and provide better subjective and objective visual qualities in Wyner-Ziv CODEC.

• The Transactions of the Korean Institute of Power Electronics
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• v.10 no.2
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• pp.109-116
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• 2005

The high performance drives of the slotless Permanent Magnet Brushless DC(PM BLDC) motor can be achieved by the current control, where the currents flow according to the rotor position and the current phase is suitably controlled according to the operational condition. Rotor position information can be provided by Hall-IC or sensorless algorithm. So, the Hall-ICs are set up in this motor to detect the main flux from the rotor. Instead of using three Hall-ICs and encoder, this paper uses only two Hall-ICs for the permanent magnet rotor position and the speed feedback signals, and uses a micro-controller of 16-bit type (80C196KC). Also because of low resolution obtained by using Hall-IC even low-cost and simple structure, to improve the wide range of speed response characteristic more exactly, we propose the rotor position signal synthesizer using PLL circuit based on two Hall-ICs.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.11C
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• pp.1541-1550
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• 2004

In this paper, we propose an advanced hardware architecture for fast multi-resolution motion estimation of the video coding standard MPEG-1,2 and MPEG-4 AVC. We describe the algorithm and derive hardware architecture emphasizing the importance of area for low cost and fast operation by using the shared memory, the special ram architecture, the motion vector for 4 pixel x 4 pixel, the spiral search and so on. The proposed architecture has been verified by ARM-interfaced emulation board using Excalibur Altera FPGA and also by ASIC synthesis using Samsung 0.18 m CMOS cell library. The ASIC synthesis result shows that the proposed hardware can operate at 140 MHz, processing more than 1,100 QCIF video frames or 70 4CIF video frames per second. The hardware is going to be used as a core module when implementing a complete MPEG-4 AVC video encoder ASIC for real-time multimedia application.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.2
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• pp.163-171
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• 2016

In order to detect the exact position of high-speed train, it is necessary to obtain location information from the transponder tag installed along the track. In this paper, we proposed parallel descrambling scheme for high-speed railway transponder system, which aims for reducing the processing time required to decode telegram. Since a telegram is stored in a tag after information bits are scrambled by an encoder, decoding procedure includes descrambling of received telegram to recover the original information bits. By analyzing the structure of the descrambling shift register circuit, we proposed a parallel descrambling scheme for fast decoding of telegram. By comparing the required number of clocks, it is shown that the proposed scheme significantly outperforms the original one.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.1
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• pp.51-57
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• 2016

This paper describes the physical layer modem structure of Giga KOREA 5G system which is being developed by ETRI as a 5G telecommunications prototype. The objective of Giga KOREA 5G system is supporting maximum 100 Gbps data rate for each cell with wide-bandwidth baseband station and mobile station prototypes in mmWave (10~40 GHz) environment. To achieve this objective, its physical layer is composed of high performance baseband station as well as mobile station and their OFDM TDD modems. The important features of Giga KOREA 5G physical layer are carrier aggregation, multiple receiving beam searching in mobile station, high data rate channel encoder and decoder and high speed modulation and demodulation functions.

• Journal of Information Processing Systems
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• v.16 no.1
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• pp.6-29
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• 2020

Biometrics identification using multiple modalities has attracted the attention of many researchers as it produces more robust and trustworthy results than single modality biometrics. In this paper, we present a novel multimodal recognition system that trains a deep learning network to automatically learn features after extracting multiple biometric modalities from a single data source, i.e., facial video clips. Utilizing different modalities, i.e., left ear, left profile face, frontal face, right profile face, and right ear, present in the facial video clips, we train supervised denoising auto-encoders to automatically extract robust and non-redundant features. The automatically learned features are then used to train modality specific sparse classifiers to perform the multimodal recognition. Moreover, the proposed technique has proven robust when some of the above modalities were missing during the testing. The proposed system has three main components that are responsible for detection, which consists of modality specific detectors to automatically detect images of different modalities present in facial video clips; feature selection, which uses supervised denoising sparse auto-encoders network to capture discriminative representations that are robust to the illumination and pose variations; and classification, which consists of a set of modality specific sparse representation classifiers for unimodal recognition, followed by score level fusion of the recognition results of the available modalities. Experiments conducted on the constrained facial video dataset (WVU) and the unconstrained facial video dataset (HONDA/UCSD), resulted in a 99.17% and 97.14% Rank-1 recognition rates, respectively. The multimodal recognition accuracy demonstrates the superiority and robustness of the proposed approach irrespective of the illumination, non-planar movement, and pose variations present in the video clips even in the situation of missing modalities.

• The KIPS Transactions:PartB
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• v.12B no.7 s.103
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• pp.745-754
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• 2005

This paper proposes an information hiding algorithm using channel coding technique which can be used to detect transmission errors and to protect copyright for MPEG-2 video The watermark signal is generated by applying copyright information of video data to a convolutional encoder, and the signal is embedded into macro blocks in every frame while encoding to MPEG-2 video stream In the decoder, the embedded signal is detected from macro blocks in every frame, and the detected signal is used to localize transmission errors in the video stream. The detected signal can also be used to claim ownership of the video data by decoding it to the copyright Information. In this stage, errors in the detected watermark signal can be corrected by channel decoder. The 3 video sequences which consist of 300 frames each are applied to the proposed MPEG-2 codec. Experimental results show that the proposed method can detect transmission errors in the video stream while decoding and it can also reconstruct copyright information more correctly than the conventional method.

• Journal of Broadcast Engineering
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• v.9 no.4 s.25
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• pp.371-383
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• 2004

In this paper we consider technological requirements to broadcast digital television signals using single frequency networks (SFN) in the Advanced Television Systems Committee (ATSC) transmission systems and propose equalization digital on-channel repeater (EDOCR) that overcomes the limitations of conventional digital on-channel repeaters (DOCRs). Since there are no forward error correction (FEC) decoder and encoder, the EDOCR does not have an ambiguity problem. In addition, since an adaptive equalizer in the EDOCR removes multi-path signals, additive white Gaussian noise (A WGN), and feedback signal due to low antenna isolation, the EDOCR may have good output signal quality with high power.