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Sung-joon Park – One of the best experts on this subject based on the ideXlab platform.
ICC – Jointly optimized quadrature Amplitude Modulation2016 IEEE International Conference on Communications (ICC), 2016Co-Authors: Sung-joon ParkAbstract:
Quadrature Amplitude Modulation has been widely used for high-speed data transmission in modern digital communication systems. In this work, a generalized quadrature Amplitude Modulation which relaxes the constraint of square lattice is suggested to improve the joint performance of Modulation and coding. Bitwise log-likelihood ratios and input signal-to-noise ratios for decoder are analyzed and the strategy minimizing the probability of decoding error is investigated. The analytical argument is consolidated by conducting simulations with a turbo code. According to results, the proposed scheme presents a power gain which depends on Es/N0 and a Modulation order.
performance analysis of triangular quadrature Amplitude Modulation in awgn channelIEEE Communications Letters, 2012Co-Authors: Sung-joon ParkAbstract:
Recently, the triangular quadrature Amplitude Modulation (TQAM) whose signal points are regularly distributed at the vertexes of contiguous equilateral triangles was proposed. In this paper, we derive the general formula calculating the average energy per symbol of the TQAM and find out that the asymptotic power gain of the TQAM over the well-known square quadrature Amplitude Modulation (SQAM) is 0.5799 dB. We also analyze the symbol error rate (SER) and the bit error rate (BER) of the TQAM and compare them with the error performances obtained through computer simulation. Analytical and simulation results coincide at a wide range of signal to noise power ratio (SNR). The power gain increases gradually and approaches the asymptotic value as Modulation order increases and target error rate decreases.
triangular quadrature Amplitude ModulationIEEE Communications Letters, 2007Co-Authors: Sung-joon ParkAbstract:
The square quadrature Amplitude Modulation (QAM) has been widely used for decades. Though it is not optimum in the sense of power efficiency, simple detection makes it in use for numerous digital communication systems deploying high-order Modulation. In this paper, we propose new signal sets which make an effective use of limited power resource. We also suggest simple detection methods for the proposed signal sets to be meaningful from a point of view of implementation. The newly proposed constellations can provide advantages of 0.46 dB and 0.55 dB in signal-to-noise ratio over the square QAM in 16-ary and 64-ary signal sets while keeping low complexity for detection
Lu Trong Khiem Nguyen – One of the best experts on this subject based on the ideXlab platform.
Amplitude Modulation of water waves governed by Boussinesq’s equationNonlinear Dynamics, 2015Co-Authors: Lu Trong Khiem NguyenAbstract:
This paper derives the equations of Amplitude Modulation of shallow water waves from the scalar Boussinesq’s (BSQ) equation by using the variational-asymptotic method. Two asymptotic solutions describing the Amplitude Modulation of trains of solitons and of positons are obtained. The comparison with the exact solutions of BSQ equation shows quite excellent agreement.
Amplitude Modulation of waves governed by Korteweg-de, 2014Co-Authors: Khanh Chau, Lu Trong Khiem Nguyen, Lehrstuhl Für MechanikAbstract:
Using the variational-asymptotic method we develop the theory of Amplitude Modulation of waves governed by Korteweg–de Vries (KdV) equation. Two asymptotic solutions describing the Amplitude Modulation of trains of solitons and of positons are obtained. The comparison with the exact solutions of KdV equation shows quite excellent agreement.
Amplitude Modulation of waves governed by Korteweg–de Vries equationInternational Journal of Engineering Science, 2014Co-Authors: Lu Trong Khiem NguyenAbstract:
Abstract Using the variational-asymptotic method we develop the theory of Amplitude Modulation of waves governed by Korteweg–de Vries (KdV) equation. Two asymptotic solutions describing the Amplitude Modulation of trains of solitons and of positons are obtained. The comparison with the exact solutions of KdV equation shows quite excellent agreement.
Gary J Rose – One of the best experts on this subject based on the ideXlab platform.
interval integration underlies Amplitude Modulation band suppression selectivity in the anuran midbrainJournal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 2003Co-Authors: Christofer J Edwards, Gary J RoseAbstract:
We examined the mechanisms that underlie ‘band-suppression’ Amplitude Modulation selectivity in the auditory midbrain of anurans. Band-suppression neurons respond well to low (5–10 Hz) and high (>70 Hz) rates of sinusoidal Amplitude Modulation, but poorly, if at all, to intermediate rates. The effectiveness of slow rates of sinusoidal Amplitude Modulation is due to the long duration of individual ‘pulses’; short-duration pulses (<10 ms) failed to elicit spikes when presented at 5–10 pulses s−1. Each unit responded only after a threshold number of pulses (median=3, range=2–5) were delivered at an optimal rate. The salient stimulus feature was the number of consecutive interpulse intervals that were within a cell-specific tolerance. This interval-integrating process could be reset by a single long interval, even if preceded by a suprathreshold number of intervals. These findings indicate that band-suppression units are a subset of interval-integrating neurons. Band-suppression neurons differed from band-pass interval-integrating cells in having lower interval-number thresholds and broader interval tolerance. We suggest that these properties increase the probability of a postsynaptic spike, given a particular temporal pattern of afferent action potentials in response to long-duration pulses, i.e., predispose them to respond to slow rates of Amplitude Modulation. Modeling evidence is provided that supports this conclusion.