Cell outage compensation(COC) is a self-healing function of the self-organizing networks(SONs) concept for mobile wireless networks. In order to compensate the outage cell autonomously, this paper drives a solution fo...Cell outage compensation(COC) is a self-healing function of the self-organizing networks(SONs) concept for mobile wireless networks. In order to compensate the outage cell autonomously, this paper drives a solution for COC. This method is based on coordinated multiple points(Co MP) transmission and tilt adjusting. Firstly, the paper takes the coordinated pattern and tilt as the optimization objects. Then, it defines the rational objectives and the evaluation function of the situation and analysis the optimization model. Finally, based on the effective genetic algorithm(GA), the compensation mechanism is proposed. Simulation results show that this solution is better than the elder solutions in terms of coverage, interference, and throughput.展开更多
In the spaceborne/airborne forward-looking bistatic syn- thetic aperture radar （SA-FBSAR）, due to the system platforms＇ remarkable velocity difference and the forward-looking mode, the range cell migration （RCM） ...In the spaceborne/airborne forward-looking bistatic syn- thetic aperture radar （SA-FBSAR）, due to the system platforms＇ remarkable velocity difference and the forward-looking mode, the range cell migration （RCM） not only depends on the target＇s two- dimensional location, but also varies with the range location non- linearly. And the nonlinearity is not just the slight deviation from the linear part, but exhibits evident nonlinear departure in the RCM trajectory. If the RCM is not properly corrected, nonlinear image distortions would occur. Based on the RCM model, a modified two-step RCM compensation （RCMC） method for SA-FBSAR is proposed. In this method, firstly the azimuth-dependent RCM is compensated by the scaling Fourier transform and the phase multi- plication. And then the range-dependent RCM is removed through interpolation. The effectiveness of the proposed RCMC method is verified by the simulation results of both point scatterers and area targets.展开更多
This paper presents a controllable resistor, which is formed by a MOS-resistor working in the deep triangle region and an auxiliary circuit. The auxiliary circuit can generate the gate-source voltage which is proporti...This paper presents a controllable resistor, which is formed by a MOS-resistor working in the deep triangle region and an auxiliary circuit. The auxiliary circuit can generate the gate-source voltage which is proportional to the output current of an low dropout regulator for the MOS-resistor. Thus, the equivalent output resistance of the MOS-resistor is inversely proportional to the output current, which is a suitable feature for pole-zero tracking frequency compensation methods. By switching the type of the MOS-resistor and current direction through the auxiliary circuit, the controllable resistor can be suitable for different applications. Three pole-zero tracking frequency compensation methods based on a single Miller capacitor with hulling resistor, unit-gain compensation cell and pseudo-ESR （equivalent serial resistor of load capacitor） power stage have been realized by this controllable resistor. Their advantages and limitations are discussed and verified by simulation results.展开更多
基金supported by National Natural Science Foundation of China(61271187)the Hi-Tech Research and Development Program of China(2014AA01A701) and BUPT2014RC1104
文摘Cell outage compensation(COC) is a self-healing function of the self-organizing networks(SONs) concept for mobile wireless networks. In order to compensate the outage cell autonomously, this paper drives a solution for COC. This method is based on coordinated multiple points(Co MP) transmission and tilt adjusting. Firstly, the paper takes the coordinated pattern and tilt as the optimization objects. Then, it defines the rational objectives and the evaluation function of the situation and analysis the optimization model. Finally, based on the effective genetic algorithm(GA), the compensation mechanism is proposed. Simulation results show that this solution is better than the elder solutions in terms of coverage, interference, and throughput.
基金supported by the National Natural Science Foundation of China (61102143)the Fundamentl Research Funds for the Central Universities (ZYGX2011x003)
文摘In the spaceborne/airborne forward-looking bistatic syn- thetic aperture radar （SA-FBSAR）, due to the system platforms＇ remarkable velocity difference and the forward-looking mode, the range cell migration （RCM） not only depends on the target＇s two- dimensional location, but also varies with the range location non- linearly. And the nonlinearity is not just the slight deviation from the linear part, but exhibits evident nonlinear departure in the RCM trajectory. If the RCM is not properly corrected, nonlinear image distortions would occur. Based on the RCM model, a modified two-step RCM compensation （RCMC） method for SA-FBSAR is proposed. In this method, firstly the azimuth-dependent RCM is compensated by the scaling Fourier transform and the phase multi- plication. And then the range-dependent RCM is removed through interpolation. The effectiveness of the proposed RCMC method is verified by the simulation results of both point scatterers and area targets.
基金Project supported by the Key Science and Technology Project of Zhejiang Province,China (No.2007C21021)
文摘This paper presents a controllable resistor, which is formed by a MOS-resistor working in the deep triangle region and an auxiliary circuit. The auxiliary circuit can generate the gate-source voltage which is proportional to the output current of an low dropout regulator for the MOS-resistor. Thus, the equivalent output resistance of the MOS-resistor is inversely proportional to the output current, which is a suitable feature for pole-zero tracking frequency compensation methods. By switching the type of the MOS-resistor and current direction through the auxiliary circuit, the controllable resistor can be suitable for different applications. Three pole-zero tracking frequency compensation methods based on a single Miller capacitor with hulling resistor, unit-gain compensation cell and pseudo-ESR （equivalent serial resistor of load capacitor） power stage have been realized by this controllable resistor. Their advantages and limitations are discussed and verified by simulation results.
