摘要:

AbstractAn active RC low‐pass filter using two high‐gain amplifiers with bridge feedback is described which serves as terminating unit of a PCM system channel. Some conditions derived from telecommunication applications and effecting the choice of the filter structure are discussed in detail, and the principles guaranteeing imaginary zeros under the condition of absolute stability of the filter sections are explained. The measurement results confirm that, using the method described, the fairly severe requirements, particularly the high pass‐band constancy demanded for units of telecommunication equipments, can be met at an economical

ISSN:0098-9886    

DOI:10.1002/cta.4490010402

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1973

数据来源: WILEY

摘要:

AbstractFor wave digital filters, basic theorems which, although being more general, have a similarity to the difference form of Tellegen's theorem for classical networks, are derived, and the properties of reciprocity and inter‐reciprocity are defined. To each wave digital filter, there corresponds an entire family of transposed wave digital filters; each of these is inter‐reciprocal with the original one.Two types of transposition, called intrinsic and elementary transposition, are of particular importance. For these, the number of multipliers is the same after transposition as before, which is of interest for obtaining equivalent realizations. Intrinsic and elementary transposition are related to transposition (in the classical sense) and duality in the reference filter from which the wave digital filter is deri

ISSN:0098-9886    

DOI:10.1002/cta.4490010403

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1973

数据来源: WILEY

摘要:

AbstractThe paper begins with an investigation of the scattering properties of commensurate TEM transmission line networks, and emphasis is placed upon the distinction between normal networks and general (including non‐normal) networks.It is then shown that the state space concept of linear discrete systems is applicable to these networks. This provides a general and powerful systemtheoretical method for determining the network behaviour in the time and frequency domains. The waves on the transmission line elements are chosen as state variables; and for the important technical case of normal networks it is shown that each transmission line element contributes one state variable only. The entries in the state space matrices are formed by the scattering parameters of the connections and endings of the line elements; and the general method of obtaining these matrices is explained by detailed examples.An automatic network analysis program based on the state space approach needs only matrix multiplications. The program works primarily in the time domain, and the frequency behaviour is then computed by Fast Fourier Transform. The advantages of the program are demonstrated by a typical example.Finally an application to digital filters imitating TEM transmission line networks is presente

ISSN:0098-9886    

DOI:10.1002/cta.4490010404

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1973

数据来源: WILEY

摘要:

AbstractThe conventional method of designing stepped impedance transmission line networks from gain functions requires the use of a factorization process to obtain a passive input impedance, and then the application of Richards Theorem to determine the element values. A new technique is presented based upon the determination of the Fourier coefficients of the return loss function from which the element values may be obtained immediately for the minimum phase reflection coefficient without any factorization process or synthesis procedure. It is believed that this new technique may be extended directly to the design of mixed lumped‐distributed transmission line networks whereas the conventional approach may no

ISSN:0098-9886    

DOI:10.1002/cta.4490010405

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1973

数据来源: WILEY

摘要:

AbstractA state space analysis is given of the networks containing periodically operated switches, by using a new approach based on the concept of time constant multiplication rather than on the conventional concept of resistance multiplication.The transfer function of two‐port networks containing P.O.S. is derived from a state model that does not require a detailed topological analysis of the network.The number and the location of the switches is discussed with particular reference to the problem of their minimization.Experimental results are given by illustrating an application of variable filters to the realization of a spaceborne spectrum analyze

ISSN:0098-9886    

DOI:10.1002/cta.4490010406

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1973

数据来源: WILEY

摘要:

AbstractThe incorporation of a lossy stabilizing element into a microwave oscillator circuit is described. Such an element facilitates the application of dc bias to the circuit, and makes it unlikely that oscillations occur at undesired frequencies. There follows a description of configurations that have been used for solid‐state oscillators at frequencies from 8 GHz to over 110 GHz. These circuits have two outstanding features which facilitate characterization both of the circuits themselves and of diodes mounted therei

ISSN:0098-9886    

DOI:10.1002/cta.4490010407

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1973

数据来源: WILEY

摘要:

AbstractThe approximation problem in synthesis of RC distributed networks is discussed. The synthesis methods based on transcendental frequency transformations are considered. A method of graphical approximation of a required network function magnitude is proposed. The modified frequency is introduced to ensure asymptotic behaviour of the logarithmic plots and the relevant design‐charts are presented. They enable us to find out the locations of zeros of normalized factors from the prescribed values of the magnitude and frequency. A method of two‐step analytical approximation is also included. The proposed methods are very useful for the preliminary approximation that saves time for further numerical procedures by a computer. The methods presented are illustrated by an exam

ISSN:0098-9886    

DOI:10.1002/cta.4490010408

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1973

数据来源: WILEY

摘要:

AbstractLadder network functions are obtained using signal flow graph and flow graph techniques. A procedure is developed, using a flow graph analysis, for enumerating by inspection and without duplication the trees of the graph of a ladder network.

ISSN:0098-9886    

DOI:10.1002/cta.4490010409

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1973

数据来源: WILEY

ISSN:0098-9886    

DOI:10.1002/cta.4490010401

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1973

数据来源: WILEY