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ANTENTOP- 02- 2003, # 003

Jagadis Chandra Bose

 

 

 

At this issue I want to present stuff about Jagadis Chandra Bose, an Indian inventor. "J.C. Bose was at least 60 years ahead of his time", as Sir Neville Mott, Nobel Laureate, remarked in 1977. Let's remembered that great man!

 

 

1997 IEEE.  Reprinted, with permission, from:

 

IEEE Transactions on Microwave Theory and Techniques, December 1997, Vol. 45, No. 12, pp.2267-2273.

 

 

D.T. Emerson

National Radio Astronomy Observatory(1)

 

949 N. Cherry Avenue

Tucson, Arizona 85721

E-mail: demerson@nrao.edu

 

Based on material presented at the IEEE-MTT-S International Microwave Symposium in Denver, CO, June 8-13, 1997; this appeared in the 1997 IEEE MTT-S International Microwave Symposium Digest, Volume 2, ISSN 0149-645X, pp.553-556. The full article was published in the IEEE Transactions on Microwave Theory and Techniques, December 1997, Vol. 45, No. 12, pp.2267-2273. This WWW version has some additional photographs, and color images. Copyright held by the author and the IEEE.

 

(1)The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.

 

ABSTRACT

 

Just one hundred years ago, J.C. Bose described to the Royal Institution in London his research carried out in Calcutta at millimeter wavelengths. He used waveguides, horn antennas, dielectric lenses, various polarizers and even semiconductors at frequencies as high as 60 GHz; much of his original equipment is still in existence, now at the Bose Institute in Calcutta. Some concepts from his original 1897 papers have been incorporated into a new 1.3-mm multi-beam receiver now in use on the NRAO 12 Meter Telescope.

 

INTRODUCTION

 

James Clerk Maxwell's equations predicting the existence of electromagnetic radiation propagating at the speed of light were made public in 1865; in 1888 Hertz had demonstrated generation of electromagnetic waves, and that their properties were similar to those of light [1]. Before the start of the twentieth century, many of the concepts now familiar in microwaves had been developed [2,3]: the list includes the cylindrical parabolic reflector, dielectric lens, microwave absorbers, the cavity radiator, the radiating iris and the pyramidal electromagnetic horn. Round, square and

 

rectangular waveguides were used, with experimental development anticipating by several years Rayleigh's 1896 theoretical solution [4] for waveguide modes. Many microwave components in use were quasi-optical - a term first introduced by Oliver Lodge [5]. Righi in 1897 published a treatise on microwave optics [6].

Hertz had used a wavelength of 66 cm; other post-Hertzian pre-1900 experimenters used wavelengths well into the short cm-wave region, with Bose in Calcutta [7,8] and Lebedew in Moscow [9] independently performing experiments at wavelengths as short as 5 and 6 mm.

 

THE RESEARCHES OF J.C. BOSE

Jagadis Chandra Bose [10,11,12] was born in India in 1858. He received his education first in India, until in 1880 he went to England to study medicine at the University of London. Within a year he moved to Cambridge to take up a scholarship to study Natural Science at Christ's College Cambridge. One of his lecturers at Cambridge was Professor Rayleigh, who clearly had a profound influence on his later work. In 1884 Bose was awarded a B.A. from Cambridge, but also a B.Sc. from London University. Bose then returned to India, taking up a post initially as officiating professor of physics at the Presidency College in

 

 

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