• Title/Summary/Keyword: ASK Modulation

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Acoustic Wireless Communication from Smart Phone to Hearing Aid (스마트폰에서 보청기로의 음향 무선 통신)

  • Jarng, Soon Suck
    • The Journal of the Acoustical Society of Korea
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    • v.34 no.2
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    • pp.91-97
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    • 2015
  • In this paper, wireless communication from a smart phone to a hearing aid using audible frequency band sound was considered. 1kHz single channel carrier frequency was applied for amplitude shift keying (ASK) binary data modulation, and the result of the transmission and reception was tested. The overall system process was precisely explained and experimentally evaluated. The result will be applied for realizing a digital hearing aid with remote control feature by a smart phone.

Implementation of Binary Search Algorithm for RFID system and A Study of Performance with RFID system (RFID용 이진 검색 알고리즘의 구현 및 시스템 성능에 관한 연구)

  • Cho, Kyung-Chul;Son, Sung-Chan;Kim, Young-Cheol
    • 한국정보통신설비학회:학술대회논문집
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    • 2005.08a
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    • pp.285-289
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    • 2005
  • In recent years, RFID is widely used in industrial applications including factory, material flow, logistics and defense areas. In this paper, we developed a RFID baseband system with ASK modulation and convolutional channel code. A commercial ASK RF module is used its frequency range in $350{\sim}351$MHz and power is 10mW and the convolution code is constraint length k=3 and rate R=1/2 The performance is measured implemented the binary search algorithm as anti-collision method and we show the wave shapes whit collision occurrence.

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Design of the Train Identification Module Using a RFID System in 27.095MHz Bandwidth (27.095MHz 대역의 무선인식 시스템을 이용한 열차인식 모듈의 설계)

  • Yoon Shang-Moon;Baek Sun-Ki;Park Myeon-Gyu;Lee Kye-Seo
    • Proceedings of the KSR Conference
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    • 2003.05a
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    • pp.487-492
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    • 2003
  • This paper designs a Korea train identification module using a RFID system. Frequency bandwidth transmits and receives messages using the 27.095Mhz and 4.234Mhz in the ISM bandwidth. The mode of the modulation uses a transmission ASK and a receiving FSK. And it uses a reader and transponder using an active transponder. We use the loop antenna which the antenna has the directional.

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Performances of Digital Amplitude-Frequency Modulation System (디지틀 진폭-주파수 변조 시스템의 특성)

  • 홍현성;남호법;조성준
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.9 no.4
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    • pp.157-162
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    • 1984
  • The data transmission in radio channel is mainly influenced by interfere and random noise. The increasing man-made impulsive noise environment has the necessity to consider impulsive noise than conventional white gaussian noise in digital communications. In this paper, we have investigated the error rate performance of hybrid modulation system. AFSK, which is composed of ASK and FSK in the environment of electromaganetic interference (EMI), especially impulsive noise.

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Involvement of miR-Let7A in inflammatory response and cell survival/apoptosis regulated by resveratrol in THP-1 macrophage

  • Song, Juhyun;Jun, Mira;Ahn, Mok-Ryeon;Kim, Oh Yoen
    • Nutrition Research and Practice
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    • v.10 no.4
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    • pp.377-384
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    • 2016
  • BACKGROUND/OBJECTIVES: Resveratrol, a natural polyphenol, has multiple functions in cellular responses including apoptosis, survival, and differentiation. It also participates in the regulation of inflammatory response and oxidative stress. MicroRNA-Let-7A (miR-Let7A), known as a tumor suppressor miRNA, was recently reported to play a crucial role in both inflammation and apoptosis. Therefore, we examined involvement of miR-Let7A in the modulation of inflammation and cell survival/apoptosis regulated by resveratrol. MATERIALS/METHODS: mRNA expression of pro-/anti-inflammatory cytokines and sirtuin 1 (SIRT1), and protein expression of apoptosis signal-regulating kinase 1 (ASK1), p-ASK1, and caspase-3 and cleaved caspase-3 were measured, and cell viability and Hoechst/PI staining for apoptosis were observed in Lipopolysaccharide (LPS)-stimulated human THP-1 macrophages with the treatment of resveratrol and/or miR-Let7A overexpression. RESULTS: Pre-treatment with resveratrol ($25-200{\mu}M$) resulted in significant recovery of the reduced cell viabilities under LPS-induced inflammatory condition and in markedly increased expression of miR-Let7A in non-stimulated or LPS-stimulated cells. Increased mRNA levels of tumor necrosis $factor-{\alpha}$ and interleukin (IL)-6 induced by LPS were significantly attenuated, and decreased levels of IL-10 and brain-derived neurotrophic factor were significantly restored by resveratrol and miR-Let7A overexpression, respectively, or in combination. Decreased expression of IL-4 mRNA by LPS stimulation was also significantly increased by miR-Let7A overexpression co-treated with resveratrol. In addition, decreased SIRT1 mRNA levels, and increased p-ASK1 levels and PI-positive cells by LPS stimulation were significantly restored by resveratrol and miR-Let7A overexpression, respectively, or in combination. CONCLUSIONS: miR-Let7A may be involved in the inflammatory response and cell survival/apoptosis modulated by resveratrol in human THP-1 macrophages.

A Comparison of the Error Rate Performances of Various Digitally Modulated Signals in the Environment of Tone/Multiple Interferer (톤간섭 및 다중간섭하에서 제반 디지탈 변조신호의 오율특성 비교)

  • 공병옥;조성준
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.15 no.10
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    • pp.797-810
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    • 1990
  • The error rate equations of digitally modulated signals transmitted through the Gaussian noise and tone multiple interference channel have been derived. Using the derived equations of error probabilities in the environments of Gaussian noise tone interferer and Gaussian noise multiple interferer, the error rate performances of various digitally modulated signals have been evaluated, and compared in graphs as a function of average carrier to tone interferer power ratio(CIR), average carrier to multiple interferer power ratio(CIT) and the average carrer-to-Gaussian noise powr ratio(CIR). In this paper, the modulation schemes such as amplitude shift keying (ASK), phase shift keying(PSK), frequency shift keying(FSK), minimum shift keying(MSK), quadrature amplitud modulation(QAM) and amplitude phase shift keying(APK) have been selected for the study of performance comparison. The results of comparison show us that, in low bits/sec/Hz, PSK is superior to the other schemes, but in high bits/sec/Hz, mixed multi ary type is better than single multi ary type. And in strong noise evironment, the multiple interferer has much influence than tone interferer, however, in low noise environment. the mojor error factor is tone interferer. But tone interference effect nearly disappears over specified CIR level about 20[dB]. And the modulation schemes using amplitude are heavily influenced by multiple interference.

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A Study on the Reliability Improvement of RFID System (REID 시스템의 신뢰성 향상에 관한 연구)

  • Ham, Jung-Ki;Lee, Cheong-Jin;Kwon, Oh-Heung
    • Journal of Digital Contents Society
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    • v.7 no.3
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    • pp.169-174
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    • 2006
  • In recent years, RFID is widely used in industrial applications including factory, material flow, logistics and defense areas. In this paper, The convolutional encoding and viterbi decoding is also implemented to improve the system performance. in an FPGA chip. The used convolution code is constraint length K=3 and rate R=1/2. The length of command frame and response frame is total of 48bits consisting of SOF 8 bits, command 16 bits, CRC 16 bit, and EOF 8 bits. And also the frame error rates are measured under the channel of line-of-sight and non line-of-sight, respectively. The performances are analyzed with FSK modulation only and FSK modulation added with convolutional encoding. These two measured results are compared with that of a RFID system with ASK modulation.

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Design of Multipath Adaptive BISMO-Algorithm in the Underwater Communication (수중 통신시 다중경로 적응 BISMO (Bi-Switch Modulation)알고리즘 설계)

  • Im, Byung-Ook;Shim, Tae-Bo
    • The Journal of the Acoustical Society of Korea
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    • v.27 no.7
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    • pp.342-349
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    • 2008
  • Multipath makes clear message transfer difficult in the underwater communication. To solve this problem, we propose a new method producing proper MFSP (Modulation Frequency Shift Period) which could be obtained by calculating time delay caused by different path from a transmitter to a receiver. At the transmitter end, messages were divided according to the size of the MFSP and transmitted accordingly alternating Frequency. At the receiver end, the received messages were demodulated in order to recover the original message by the adaptive BISMO algorithm which is constructed at the algorithm design stage. Adaptive MFSP and estimated BER (Bit Error Rate) were calculated through simulation test.

Performance of Vehicle Detection Using Alamouti for ITS (ITS를 위한 Alamouti 기법을 이용한 차량 검출 성능 분석)

  • Kim, Seung-Jong;Park, In-Hwan;Kim, Jin-Young
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.10 no.3
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    • pp.79-84
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    • 2011
  • In this paper, we analyzed performance of vehicle detection for ITS (Intelligent Transport System) applications. We simulated the vehicle detection at Hi-Pass System is based on DSRC (Dedicated Short Range Communication). DSRC is a wireless network using ITS, including GPS (Global Positioning System) satellites in conjunction with the national transportation system. The system performance is evaluated in terms of bit error probability. In the simulation, the vehicle speed is set at 60 km/h and carrier frequency is 5.8 GHz. Wireless channel is modeled as the Rician fading channel. In the transmitter, the ASK (amplitude shift keying) modulation scheme is applied. From simulation results, we confirmed that performance of applied Alamouti scheme is better than other systems.

Development of Electronic Identification Unit Using RF (RF를 이용한 전자 개체 인식 장치 개발)

  • 조성인;류관희;안광재;김유용;유윤관
    • Journal of Biosystems Engineering
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    • v.27 no.5
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    • pp.459-466
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    • 2002
  • In Korea, a need of automatic dairy farm management system has been increased to lower production cost and to strengthen international competition. However, the present management system was mostly relied on foreign technologies and caused some problems in post management and after-sales services. Therefore, though there is a problem of price and quality at present, domestic technologies of the management system should be developed for the long run. This study was conducted to develop an electronic identification unit for an automatic dairy farm management system. The developed system was consisted of a tag, a reader, a switching circuit, and a personal computer. The tag attachable to each individual cow was developed to transmit individual radio frequency(RF) code into the air with modulation of ASK(amplitude shift keying). And the switching circuit was added to avoid confusion on reception and transmittance. The reader attached to a feeding device was developed to transmit activating signal periodically and to identify code of the individual tag when the tag was approached to the device. The reader was consisted of an active filter, a detecter, a comparator and a microcontroller. The test result was feasible enough to apply it for the automatic farm management system and the identified maximum distance was about 37cm.