Results 271 to 280 of about 220,278 (302)

Imbalance in Phased Arrays of Dipoles Induced by Scanning

2019 IEEE Texas Symposium on Wireless and Microwave Circuits and Systems (WMCS), 2019
Dipoles driven by baluns can become unbalanced by external influences. Such dipole elements in a phased array can become unbalanced due to the phase shift factor u 0 used to scan the array. This scanning-induced imbalance is distinct from imbalance at the edge of the array induced by truncation.
James S. McLean, Heinrich Foltz
openaire   +1 more source

Joint compensation of IQ imbalance and phase noise

The 57th IEEE Semiannual Vehicular Technology Conference, 2003. VTC 2003-Spring., 2004
Today a lot of effort is spent on developing inexpensive OFDM receivers. Especially, zero-IF receivers are very appealing, because they avoid costly IF filters. However, zero-IF front-ends introduce more front-end distortion such as IQ imbalance and phase noise. Unfortunately, OFDM is very sensitive to these receiver non-idealities.
J. Tubbax, B. Come, L. Van der Perre, S. Donnay, M. Engles, C. Desset   +5 more
openaire   +1 more source

Efficient compensation of I/Q phase imbalance for digital receivers

IEEE International Conference on Communications, 2005. ICC 2005. 2005, 2005
In I/Q receivers characterized by direct conversion or low-IF operations, phase imbalance between the I and Q branches stands for a substantial issue which may degrade significantly the overall link performance. An alternative solution to high cost analog components with small tolerances which make the I/Q imbalance effect negligible is to estimate and
GIUGNO L, LOTTICI, VINCENZO, LUISE, MARCO   +2 more
openaire   +1 more source

Gain/phase imbalance and DC offset compensation in quadrature modulators

2002 IEEE International Symposium on Circuits and Systems. Proceedings (Cat. No.02CH37353), 2003
This paper describes a technique to estimate gain and phase imbalances and DC offsets in a quadrature modulator and to pre-compensate the in-phase and quadrature signals, so that image suppression is maximized and LO leakage is minimized at the modulator output.
Xinping Huang, Mario Caron
openaire   +1 more source

Networked detection of voltage imbalances for three-phase power systems

2015 IEEE 24th International Symposium on Industrial Electronics (ISIE), 2015
The problem of imbalance detection in a three-phase power network using a phasor measurement unit (PMU) is considered. In this paper, a general model for the positive sequences is presented based on time-domain PMU measurement at off-nominal frequencies.
Tirza Routtenberg, Lang Tong 0001
openaire   +1 more source

IQ imbalance and phase noise mitigation for wireless OFDM systems

2008 IEEE International Symposium on Circuits and Systems (ISCAS), 2008
OFDM systems suffer severe performance degradation in the presence of IQ imbalance and phase noise. This paper provides a new IQ imbalance estimation scheme that works under phase noise effect and multi-path channel with large delay spread. Furthermore, the proposed method can suppress the interference from neighboring subcarriers caused by phase noise.
Chung-Jin Tsai, Chun-Hao Liao, Tzi-Dar Chiueh   +2 more
openaire   +1 more source

Force imbalance in lattice Boltzmann equation for two-phase flows

Physical Review E, 2011
The capability of modeling and simulating complex interfacial dynamics of multiphase flows has been recognized as one of the main advantages of the lattice Boltzmann equation (LBE). A basic feature of two-phase LBE models, i.e., the force balance condition at the discrete lattice level of LBE, is investigated in this work.
Zhaoli, Guo, Chuguang, Zheng, Baochang, Shi   +2 more
openaire   +2 more sources

Subsynchronous resonance countermeasure using phase imbalance

IEEE Transactions on Power Systems, 1993
Since the discovery in 1970 that subsynchronous resonance (SSR) was the main cause of the shaft failures at the Mohave plant in Southern Nevada, extensive research and development efforts have been devoted to the development of effective SSR mitigation measures.
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Reducing three-phase power imbalance with electric springs

2014 IEEE 5th International Symposium on Power Electronics for Distributed Generation Systems (PEDG), 2014
Electric springs have been used previously in stabilizing mains voltage fluctuations in power grid fed by intermittent renewable energy sources. This paper describes a new three-phase electric spring circuit and its new operation in reducing power imbalance in the three-phase power system of a building.
Hui, RSY, Yan, S, Tan, SC, Lee, CK
openaire   +2 more sources

Three-phase imbalance prediction: A hazard-based method

2016 IEEE International Conference on Power and Renewable Energy (ICPRE), 2016
Three-phase power systems are widely used in high-power applications and they are designed to operate in a near-balanced fashion at a nominal frequency for optimal performance. Although a slight voltage imbalance is tolerant in real-life scenarios, a significant three-phase imbalance has detrimental effects for power delivery and even damages many key ...
null Jiye Wang, null Nan Zeng, null Hanyong Hao   +2 more
openaire   +1 more source