摘要:

Following the extension of equivalence transformations to a general class of electrical networks containing active devices such as operational amplifiers, the theory is developed to accommodate the minimisation of the sensitivity of the network response function to component variations. Theorems for passivecomponent sensitivity invariance and for updating routines applicable to the optimisation step are proved. Previous limitations imposed upon the optimisation routine by equality realisability constraints are completely eliminated by a partitioned approach. This leads to a new form of transformation. The partitioned transformation can be implemented in both discrete and continuous forms, and applied to the optimisation of component values and sensitivities in active networks

DOI:10.1049/ij-ecs.1978.0008

出版商:IEE    

年代:1978

数据来源: IET

摘要:

The paper describes a procedure for selecting from a collection of models, for the purpose of m.o.s.f.e.t. circuit simulation, a m.o.s.f.e.t. device model that provides the best trade-off between accuracy and computational efficiency. The selection method employs the concept of the accuracy-efficiency product, and is suited to a situation in which only a few models will be used to represent all the devices in the network. Another selection method is also proposed, which employs a ‘model performance function’ and is appropriate for situations in which each device in a network can be represented by a different model. The results of applying these two selection methods to a particular m.o.s.f.e.t. model library are presented

DOI:10.1049/ij-ecs.1978.0009

出版商:IEE    

年代:1978

数据来源: IET

摘要:

Gain-control systems are used to improve the performance of communication links that are subject to variation of received signal power, and in a variety of techniques designed to increase the signal/noise ratio. The system described here is intended to operate at audio frequencies with the minimum of distortion, and the gain is controlled by the amplitude of a high-frequency (50 kHz) carrier superimposed on the audio signal. Two modes of operation have been investigated, and their response when subjected to step and ramp control signals is analysed mathematically. Theoretical results are expressed in graphical form and are compared with measurements obtained from experimental prototype circuits

DOI:10.1049/ij-ecs.1978.0010

出版商:IEE    

年代:1978

数据来源: IET

摘要:

A zero-crossing phasemeter using a new phase detector is described. Because high-speed logic and ultrafast current switches are used, coupled with a new current-subtraction technique which tends to cancel out switch errors, the phasemeter is capable of functioning satisfactorily at frequencies up to 50 MHz. The phase detector, when used in conjunction with a judiciously selected control signal, has noise-rejection properties superior to conventional circuits

DOI:10.1049/ij-ecs.1978.0011

出版商:IEE    

年代:1978

数据来源: IET