• Title/Summary/Keyword: Modulation Detection

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Design of decoder for Pulse-Position Modulation with Trellis-Coded Modulation on Non-Directed Indoor Infrared Channel (간접 실내 적외선 채널에서 Pulse-Position Modulation with Trellis-Coded Modulation을 위한 복호기 설계)

  • Jeong, S.;Rho, S.
    • Proceedings of the KIEE Conference
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    • 1998.07g
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    • pp.2467-2469
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    • 1998
  • We examine the performance of high-speed non-directed infrared links using pulse-position modulation (PPM) with trellis-coded modulation (TCM) to mitigate the effects of multipath-induced intersymbol interference(ISI) on such links. Using the measured characteristics of multipath indoor infrared channels, we calculate BER curves and ISI power penalties for maximum-likelihood sequence detection of 8-PPM links using rate-2/3 trellis codes operation at 10 and 30Mb/s. Our results indicate that the suggested decoder of PPM with TCM is a very promising decoder on high-speed non-directed infrared channels.

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MIMO Detection Algorithms in Binary PAM DS UWB Communication (이진 PAM DS UWB 통신에서 MIMO 검출 기법)

  • Kang, Yun-jeong;Kim, Gil-nam;Kim, Sang-choon
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2009.05a
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    • pp.447-450
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    • 2009
  • In this paper, binary pulse-antipodal modulation (2PAM) direct-sequence (DS) ultra-wideband (UWB) system is applied to multiple input multiple output (MIMO) system using vertical bell lab layered space-time (V-BLAST) structure to achieve high-data-rate communications over indoor wireless channels. The relationship between antenna dimension and BER performance of 2PAM DS UWB MIMO system is discussed. In the receiver of UWB-MIMO system, various MIMO detection algorithms such as zero-forcing (ZF), ZF-ordered successive interference cancellation (OSIC), minimum-mean-square-error (MMSE), MMSE-OSIC and maximum likelihood (ML) are comparatively studied.

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450 Gbps Low-cost Intensity Modulation with Direct Detection (IM/DD) Wave Length Division Multiplexing (WDM-PON) for 5G Fronthaul

  • Kawan Faiq Ahmed;Asaad Mubdir Jassim Al-Hindawi
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.17 no.12
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    • pp.3310-3329
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    • 2023
  • This work designs an eighteen-channel bidirectional Intensity Modulation with Direct Detection (IM/DD) Wavelength Division Multiplexing-Passive Optical Network (WDM-PON) system. The proposed system meets the requirement of the ITU-T 5G fronthaul link suggested design in G-series Recommendations-Supplement 66. The newly designed system, with a 25Gb/s/λ data rate (450Gbps as a system capacity), has been tested and simulated using OptiSystem V.19 software. The system has been evaluated by the BER with respect to variable the optical span and CW laser power. Based on the ITU-T recommendations, the simulation results demonstrate that this system might be used as an F1 and as an Fx 5G fronthaul link for functional split choices starting from options 1 to 7a. These options are required under 25Gbps/λ for each upstream and downstream link direction. Furthermore, the proposed system utilized a bidirectional single-mode optical fiber within short optical spans of up to 10 km. The proposed system is characterized by a low-cost, simple, DSP-free and amplifier-free system with a reasonable system capacity.

Highly-sensitive Magnetic Sensor using the Amplitude-Modulation (진폭변조를 이용한 고감도 자기센서)

  • 이상훈;남태철
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1995.05a
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    • pp.90-95
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    • 1995
  • This paper describes the highly-sensitive Si magnetic sensor using the amplitude modulation in order to real ice the integrated magnetic sensor which to sensor a weak magnetic field. Generally, the most important two parameters in Hall IC which degrade the ability of magnetic detection are the variation of offset according to the variation of temperature and the noise of amplifiers. In this paper, we use a Hall element and compensator to reduce the offset and the nouse of amplifiers by Using amplititude modulation method.

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All-fiber heterodyne interferometer with phase modulation (Mach-Zehnder 광섬유 간섭계를 이용한 Heterodyne 검파 방법)

  • Jeong, Kyu-Cheol;Song, Jung-Tae;Lee, Kyung-Shik
    • Proceedings of the KIEE Conference
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    • 1998.11c
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    • pp.996-998
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    • 1998
  • We have proposed and demonstrated a novel method of heterodyne detection using all-fiber Mach-Zehnder interferometer. The method is characterized by the phase modulation with a sawtooth waveform instead of a frequency modulation in true heterodyne. The experimental results will be compared with the expected results.

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Analysis of Joint Multiband Sensing-Time M-QAM Signal Detection in Cognitive Radios

  • Tariq, Sana;Ghafoor, Abdul;Farooq, Salma Zainab
    • ETRI Journal
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    • v.34 no.6
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    • pp.892-899
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    • 2012
  • We analyze a wideband spectrum in a cognitive radio (CR) network by employing the optimal adaptive multiband sensing-time joint detection framework. This framework detects a wideband M-ary quadrature amplitude modulation (M-QAM) primary signal over multiple nonoverlapping narrowband Gaussian channels, using the energy detection technique so as to maximize the throughput in CR networks while limiting interference with the primary network. The signal detection problem is formulated as an optimization problem to maximize the aggregate achievable secondary throughput capacity by jointly optimizing the sensing duration and individual detection thresholds under the overall interference imposed on the primary network. It is shown that the detection problems can be solved as convex optimization problems if certain practical constraints are applied. Simulation results show that the framework under consideration achieves much better performance for M-QAM than for binary phase-shift keying or any real modulation scheme.

Error analysis for time-in-flight laser range finder with multiple toe amplitude modulation

  • Matsumoto-Moriyama, Masao;Mima, Kazuhiko;Ishimatsu, Takakazu
    • 제어로봇시스템학회:학술대회논문집
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    • 1993.10b
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    • pp.554-557
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    • 1993
  • The error analysis for the Time-in-Flight Laser Range Finder with Multiple Tone Amplitude Modulation relevant to the phase detection error is made. The distance can be estimated to solve the formulate which express the relationship between the absolute distance from the range finder to the object and the wavenumbers and the phases of the modulated waves by the optimization technique. The main cause of the estimation error can be considered as the phase detection error induced from the amplitude modulator and the phase detector. To clarify the phase detection error and the optimal amplitude frequency set, the numerical analysis are made.

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Quasi-Orthogonal STBC with Iterative Decoding in Bit Interleaved Coded Modulation

  • Sung, Chang-Kyung;Kim, Ji-Hoon;Lee, In-Kyu
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.33 no.4A
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    • pp.426-433
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    • 2008
  • In this paper, we present a method to improve the performance of the four transmit antenna quasi-orthogonal space-time block code (STBC) in the coded system. For the four transmit antenna case, the quasi-orthogonal STBC consists of two symbol groups which are orthogonal to each other, but intra group symbols are not. In uncoded system with the matched filter detection, constellation rotation can improve the performance. However, in coded systems, its gain is absorbed by the coding gain especially for lower rate code. We propose an iterative decoding method to improve the performance of quasi-orthogonal codes in coded systems. With conventional quasi-orthogonal STBC detection, the joint ML detection can be improved by iterative processing between the demapper and the decoder. Simulation results shows that the performance improvement is about 2dB at 1% frame error rate.

A Two-Point Modulation Spread-Spectrum Clock Generator With FIR-Embedded Binary Phase Detection and 1-Bit High-Order ΔΣ Modulation

  • Xu, Ni;Shen, Yiyu;Lv, Sitao;Liu, Han;Rhee, Woogeun;Wang, Zhihua
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.16 no.4
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    • pp.425-435
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    • 2016
  • This paper describes a spread-spectrum clock generation method by utilizing a ${\Delta}{\Sigma}$ digital PLL (DPLL) which is solely based on binary phase detection and does not require a linear time-to-digital converter (TDC) or other linear digital-to-time converter (DTC) circuitry. A 1-bit high-order ${\Delta}{\Sigma}$ modulator and a hybrid finite-impulse response (FIR) filter are employed to mitigate the phase-folding problem caused by the nonlinearity of the bang-bang phase detector (BBPD). The ${\Delta}{\Sigma}$ DPLL employs a two-point modulation technique to further enhance linearity at the turning point of a triangular modulation profile. We also show that the two-point modulation is useful for the BBPLL to improve the spread-spectrum performance by suppressing the frequency deviation at the input of the BBPD, thus reducing the peak phase deviation. Based on the proposed architecture, a 3.2 GHz spread-spectrum clock generator (SSCG) is implemented in 65 nm CMOS. Experimental results show that the proposed SSCG achieves peak power reductions of 18.5 dB and 11 dB with 10 kHz and 100 kHz resolution bandwidths respectively, consuming 6.34 mW from a 1 V supply.

Characteristics of Compensation for Distorted Optical Pulse with Initial Frequency Chirp in 3 X 40 Gbps WDM Systems Adopted Mid-Span Spectral Inversion

  • Lee, Seong-Real;Lee, Yun-Hyun
    • Journal of electromagnetic engineering and science
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    • v.3 no.2
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    • pp.79-85
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    • 2003
  • In this paper, we investigated the degree of compensation for distorted optical pulse of wavelength division multiplexed(WDM) channel with initial frequency chirp generated in optical transmitter. The WDM channel signal distortion is due to chromatic dispersion, self phase modulation(SPM) and cross phase modulation(XPM) in fiber. The considered system is 3 ${\times}$ 40 Gbps intensity modulation direct detection(IM/DD) WDM transmission systems, which adopted mid-span spectral inversion(MSSI) as compensation method. We confirmed that the effect of initial frequency chirp on compensation for signal distortion due to a SPM is gradually decreased as a dispersion coefficient of fiber becomes gradually small. But, in the aspect of a compensation for signal distortion due to both SPM and XPM, the effect of initial frequency chirp on compensation is gradually decreased as a dispersion coefficient of fiber becomes gradually large.