A novel met hod t o p artially compensate sigma2delta shap ed noise is p rop osed. By injecting t he comp en2 sation cur rent int o t he p assive loop f ilte r during t he delay time of t he p hase f requency detect or ( PFD) , a maximum reduction of t he p hase noise by about 16dB can be achieved. Comp a red t o ot he r compensation met hods , t he tech2 nique p rop osed he re is relatively simple and easy t o implement . Key building blocks f or realizing t he noise cancel2 lation , including t he delay va riable PFD and comp ensation cur rent source , a re sp ecially designed. Bot h t he behavior level and circuit level simulation results a re p resented.
标签: sigma2delta compensate injecting artially
上传时间: 2013-12-18
上传用户:qlpqlq
Abstract: A laser module designer can use a fixed resistor, mechanical pot, digital pot, or a digital-to-analogconverter (DAC) to control the laser driver's modulation and bias currents. The advantages of a programmablemethod (POT or DAC) are that the manufacturing process can be automated and digital control can be applied(e.g., to compensate for temperature). Using POTs can be a more simple approach than a DAC. There can be aslight cost advantage to using a POT, but this is usually not significant relative to other pieces of the design.Using a DAC can offer advantages, including improved linearity (translating to ease of software implementationand ability to hit the required accuracy), increased board density, a wider range of resolutions, a betteroptimization range, ease of use with a negative voltage laser driver, and unit-to-unit consistency
上传时间: 2013-11-13
上传用户:ca05991270
Power conversion by virtue of its basic role produces harmonics due to theslicing of either voltages or currents. To a large extent the pollution in theutility supply and the deterioration of the power quality has been generatedor created by non-linear converters. It is therefore ironic that power convertersshould now be used to clean up the pollution that they helped to create inthe first place.In a utility system, it is desirable to prevent harmonic currents (which resultin EMI and resonance problems) and limit reactive power flows (whichresult in transmission losses).Traditionally, shunt passive filters, comprised of tuned LC elements andcapacitor banks, were used to filter the harmonics and to compensate forreactive current due to non-linear loads. However, in practical applicationsthese methods have many disadvantages.
上传时间: 2013-11-05
上传用户:AISINI005
特点(FEATURES) 精确度0.1%满刻度(Accuracy 0.1%F.S.) 多种输入输出选择(Wide selection of input/output range) 三线式接线自动补偿线路阻抗效应(3 wire configuration automatically compensate line resistance effects) 宽范围交直流两用电源设计(Wide input range for auxiliary power) 尺寸小,稳定性高(Dimension small & High stability)
上传时间: 2013-10-17
上传用户:Huge_Brother
In this paper we describe a control methodology for catching a fast moving object with a robot manipulator, where visual information is employed to track the trajectory of the target. Sensing, planning and control are performed in real-time to cope with possible unpredictable trajectory changes of the moving target, and prediction techniques are adopted to compensate the time delays introduced by visual processing and by the robot controller. A simple but reliable model of the robot controller has been taken into account in the control architecture for improving the performance of the system. Experimental results have shown that the robot system is capable of tracking and catching an object moving on a plane at velocities of up to 700 mm/s and accelerations of up to 1500 mm/s2.
标签: methodology describe catching control
上传时间: 2014-01-12
上传用户:qq521
This approach addresses two difficulties simultaneously: 1) the range limitation of mobile robot sensors and 2) the difficulty of detecting buildings in monocular aerial images. With the suggested method building outlines can be detected faster than the mobile robot can explore the area by itself, giving the robot an ability to “see” around corners. At the same time, the approach can compensate for the absence of elevation data in segmentation of aerial images. Our experiments demonstrate that ground-level semantic information (wall estimates) allows to focus the segmentation of the aerial image to find buildings and produce a ground-level semantic map that covers a larger area than can be built using the onboard sensors.
标签: simultaneously difficulties limitation addresses
上传时间: 2014-06-11
上传用户:waitingfy
In engineering, compensation is planning for side effects or other unintended issues in a design. The design of an invention can itself also be to compensate for some other existing issue or exception. One example is in a voltage-controlled crystal oscillator (VCXO), which is normally affected not only by voltage, but to a lesser extent by temperature. A temperature-compensated version (a TCVCXO) is designed so that heat buildup within the enclosure of a transmitter or other such device will not alter the piezoelectric effect, thereby causing frequency drift. Another example is motion compensation on digital cameras and video cameras, which keep a picture steady and not blurry.
标签: compensation engineering unintended planning
上传时间: 2013-12-11
上传用户:z754970244
Abstract—Stable direct and indirect decentralized adaptive radial basis neural network controllers are presented for a class of interconnected nonlinear systems. The feedback and adaptation mechanisms for each subsystem depend only upon local measurements to provide asymptotic tracking of a reference trajectory. Due to the functional approximation capabilities of radial basis neural networks, the dynamics for each subsystem are not required to be linear in a set of unknown coeffi cients as is typically required in decentralized adaptive schemes. In addition, each subsystem is able to adaptively compensate for disturbances and interconnections with unknown bounds.
标签: decentralized controllers Abstract adaptive
上传时间: 2017-08-17
上传用户:gdgzhym