DOI:10.1049/ree.1976.0061

出版商:IERE    

年代:1976

数据来源: IET

摘要:

A review is presented of submillimetre wave generators and detectors, propagation properties of materials and the atmosphere, wave guiding structures and components, and present and potential applications for the waveband. Existing practice and active research areas are described and discussed.

DOI:10.1049/ree.1976.0062

出版商:IERE    

年代:1976

数据来源: IET

摘要:

Recent advances in the technology of medium and large scale integrated circuits (m.s.i. and l.s.i.) have made possible economical hardware implementations for real-time digital filtering. A flexible design approach for such implementations is presented. The processing mode can be varied to give any hybrid structure between the purely serial and parallel realizations. This leads to a design approach which can be adjusted to suit hardware availability. The resulting structures are modular and are in line with current trends in m.s.i. and l.s.i. technology in that they lend themselves readily to implementations using semiconductor read-only or random access memories.

DOI:10.1049/ree.1976.0063

出版商:IERE    

年代:1976

数据来源: IET

摘要:

A new generalized model for atmospheric radio noise is briefly described and justified by comparison with observed probability distributions. A special case of this generalized model is then compared to the observed noise statistics at the very low frequency end of the spectrum. This model is then applied to the detection of known signals in in the presence of noise to determine the optimal receiver structure. The performance of the detector, specified by the upper bound on the probability of error, is assessed and is seen to depend on the signal shape, the time-bandwidth product, and signal-to-noise ratio. The optimal signal to minimize the probability of error is then determined.

DOI:10.1049/ree.1976.0064

出版商:IERE    

年代:1976

数据来源: IET

摘要:

The charge-coupled device is essentially a sampled-data, analogue shift register which permits many signal processing functions to be implemented in analogue form. This paper reviews the development of these devices for communication, radar and sonar applications, and summarizes the advantages of the charge-coupled concept over digital techniques

DOI:10.1049/ree.1976.0065

出版商:IERE    

年代:1976

数据来源: IET

摘要:

The recurrent-continuant method of synthesizing a ladder network due to Holbrook is limited to the lossless quadrupoles terminated in resistance at only one end. The technique has been modified to cover the general class of lossless quadrupoles terminated in resistances at both the ends. The proposed synthesis procedure starts with a given realizable polynomial which is separated into two realizable component polynomials, one of the same order and the other of one order less under the condition that the continuants corresponding to the component polynomials are such that one becomes the first minor of the other. By applying simple mathematical manipulations, the final continuant is formed out of these continuants. The element values of the final continuant are evaluated by solving certain sets of equations. The sensitivity of the transfer function of the network with respect to the terminal resistance, the non-realizability of the characteristic polynomial for a given terminal resistance ratio, and the multiple sets of values of the circuit elements for a given characteristic have also been investigated.In the case of activeRClow-pass ladder networks Nesbitt has presented a technique for transforming the recurrent determinant into the continuant determinant provided the elements of the main diagonal of the latter are specified. His method however does not provide a solution for activeRCladder networks which are terminated in a resistance at the output end. In this paper a modified transformation technique, applicable to resistively-terminated activeRCladder networks, is proposed.

DOI:10.1049/ree.1976.0066

出版商:IERE    

年代:1976

数据来源: IET