Proceedings of the IRE

The information capacity of various communications systems is considered. Quantum effects are taken fully into account. The entropy of an electromagnetic wave having the quantum statistical properties of white noise in a single transmission mode is found, and from it the information efficiency of various possible systems may be derived. The receiving systems considered include amplifiers, heterody... View full abstract»

Action potentials recorded across membranes may have a maximum rate of rise of up to 103 v/sec and the impedance of the electrode plus the generator is of the order of 10 MΩ. Therefore, to reduce distortion of the recorded signal, it is necessary to diminish the effective capacitance of the input circuit to about 1 μμf. It is also requisite to reduce the currents which pass... View full abstract»

The need for a wide-band preamplifier to measure bioelectric potentials from a source with high internal resistance and shunt capacitance has stimulated the development of instruments which should be generally useful. Consideration is given to the simultaneous attainment of such factors as low grid current, linearity, low drift, and improved dynamic response by compensation for input capacitance. ... View full abstract»

Criteria for bandwidth limits for neutralized input capacity amplifiers are developed. The behavior of different neutralization schemes is analyzed in terms of the root locus of the system gain function. This technique permits quantitative design and evaluation of the different circuits that have been used. It makes it possible to judge the effectiveness of new approaches to the problem. It is sho... View full abstract»

The response of an elliptically polarized antenna to a quasi-monochromatic, partially polarized radio wave is treated from the standpoint of coherence theory. A general formula is derived for the available power at the terminals of a receiving antenna in terms of appropriately chosen coherency matrices for the antenna and the incident wave. It is shown that the result is formally identical with th... View full abstract»

This paper analyzes telephone communication as applied to a satellite repeater system. Particular emphasis is placed on a method of coherent reception which is important to our emerging communication satellite systems. This reception technique is not new to the field of space communications and telemetry; however, it is new to the field of common carrier telephony. As a consequence, for the class ... View full abstract»

A linear passive unilateral element, which has a high forward/backward transmission ratio at all frequencies, is realized by combining two resistances and an electromechanical gyrator according to Gamo's theory. The gyrator consists of three mechanically coupled ceramic elements, two of which may be piezomagnetic and the third piezoelectric, or two of which may be piezoelectric and the third piezo... View full abstract»

The issues of IRE Transactions listed herein have recently been published, and are now available from the Institute of Radio Engineers, Inc. The contents of each issue and, where available, abstracts of technical papers are given. View full abstract»

Compiled by the Radio Research Organization of the Department of Scientific and Industrial Research, London, England, and Published by Arrangement with that Department and Electronic Technology, Dorset House, Stamford St., London S.E. 1, England. The Index to the Abstracts and References published in the PROC. IRE from February, 1961 through January, 1962 is published by the PROC. IRE, June, 1962,... View full abstract»