• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.7
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• pp.2354-2370
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• 2015

The advantages of employing SCTP-based Concurrent Multipath Transfer (CMT) have been demonstrated to be very useful for data delivery over multi-homed wireless networks. However, there is still significant ongoing work addressing some remaining limitations and challenges. The most important concern when applying CMT to data delivery is related to handling packet reordering and buffer blocking. Another concern on this topic is that current sender-based CMT solutions seldom consider balancing the overhead and sharing the load between the sender and receiver. This paper proposes a novel Receiver-driven Cooperation-based Concurrent Multipath Transfer solution (CMT-Rev) with the following aims: (i) to balance overhead and share load between the sender and receiver, by moving some functions including congestion and flow control from the sender onto receiver; (ii) to mitigate the data reordering and buffer blocking problems, by using an adaptive receiver-cooperative path aggregation model, (iii) to adaptively transmit packets over multiple paths according to their receiver-inspired sending rate values, by employing a new receiver-aware data distribution scheduler. Simulation results show that CMT-Rev outperforms the existing CMT solutions in terms of data delivery performance.

• ETRI Journal
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• v.31 no.4
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• pp.472-474
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• 2009

In this letter, an ordered successive interference cancellation (OSIC) scheme is applied for multiple-input multiple-output (MIMO) detection in ultra-wideband (UWB) communication systems. The error rate expression of an OSIC receiver on a log-normal multipath fading channel is theoretically derived in a closed form solution. Its bit error rate performance is analytically compared with that of a zero forcing receiver in the UWB MIMO detection scheme followed by RAKE combining.

• Proceedings of the KIEE Conference
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• 1998.11b
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• pp.445-447
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• 1998

This paper shows simulation results for stability and performance of two INS/GPS integration systems. First, the code tracking error of GPS receiver is analyzed by spectrum analysis and simulated for the tight and loose INS/GPS integrations. Next, stability of the integrated systems are simulated using root locus method. As loop filter in the GPS receiver, passive filter and active filter are used and compared.

• Proceedings of the IEEK Conference
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• 2002.06a
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• pp.33-36
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• 2002

A new smart antenna scheme based on spatial FFT is proposed. By combining the output of spatial FFT, the proposed structure shows similar performance gain compared to ordinary smart antenna systems. Moreover. the proposed scheme could be easily integrated to general receiver without beam focusing module. The analysis and simulation results show that the performances of proposed scheme are comparable to ordinary smart antenna systems

• Journal of the Korean Institute of Telematics and Electronics S
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• v.35S no.5
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• pp.11-16
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• 1998

DS/CDMA systems for the high speed communication require high code rats. In discrete time CDMA receivers, the performance degradation, caused by the phase difference between transmission code and reference code, increase the sampling frquency of the receiver. This increment of the sampling frequency makes hard to implement high speed CDMA systems. This paper analyzes the SIR(signal to interference Ratio) performance of the discrete time DS/CDMA system, based on the code phase difference. The results of this paper may be useful to study a low-sampling CDMA receiver.

• Journal of Communications and Networks
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• v.10 no.1
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• pp.63-70
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• 2008

Narrow-band interference (NBI) from the coexisting narrow-band services affects the performance of ultra wideband (UWB) systems considerably due to the high power of these narrow-band signals with respect to the UWB signals. Specifically, IEEE 802.11a systems which operate around 5 GHz and overlap the band of UWB signals may interfere with UWB systems significantly. In this paper, we suggest a novel NBI suppression technique based on singular value decomposition (SVD) algorithm in time hopping UWB (TH-UWB) systems. SVD is used to approximate the interference which then is subtracted from the received signals. The algorithm precision and closed-form bit error rate (BER) expression are derived in the wireless multipath channel. Comparing with the conventional suppression methods such as a notch filter and a RAKE receiver, the proposed method is simple and robust and especially suitable for UWB systems.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.1638-1642
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• 2003

In this paper, we have analyzed the power spectra and evaluate the performance of DTMF receiver by using the quick Fourier transform(QFT) algorithm. The economical signals detection of dual-tone multifrequency(DTMF) receiver is an important factor when developing cost-effective telecommunication equipment. In experimental results, it shows that reducing memory waste and can process the real-time.

• Proceedings of the KIEE Conference
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• 2005.10b
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• pp.487-489
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• 2005

This paper proposes a symbol timing recovery method that is simple in structure and can provide high speed symbol synchronization. Transmitter and receiver are not synchronized in communication systems using digital modulation. Receiver should search the timing variation of transmitter continuously. The proposed timing recovery method searches sample position by comparing previous sample value with next sample value. This method can be applied to digital and optical transceivers with high data rate.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.63-63
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• 2000

This paper is about the method to improve the IDGPS system using receiver which is not aligned to GPS time. Transmitted data between server and user is constructed in PDDM of IS-801 rule. Pseudorange is overflowed in case of using receiver unaligned GPS time. And satellite position is miscalculated because earth rotating effect is not corrected. To solve this problem, when Pseudorange measurement is over the maximum range, the Pseudorange measurement is reset. And after the rough user position and transmit time is calculated, the precise Pseudorange measurement is calculated.

• Journal of the Optical Society of Korea
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• v.18 no.2
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• pp.124-128
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• 2014

We derive joint probability density functions (JPDFs) for two adjacent data from direct-detection optical receivers in dense wavelength-division multiplexing systems. We show that the decision using two data per bit can increase the receiver sensitivity compared with the conventional decision. Our JPDFs can be used for software-defined optical receivers enhancing the receiver sensitivities for intensity-modulated channels.