IEEE ANTENNAS AND PROPAGATION GROUP

Volume 9, K i e r 1 G-AP NEWSLCETIXR October, 1966

Send all news items and persona& to editor:

W. H, K m e r Hughes Aircraft Company, M.S. V - l l 7 Culver City, Cd i fo rn ia 9 2 3 2

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EDITOFXAL - Quo VADIS?

The survey just completed brings to mind anather question. What

new fields of antennasand propagation should we welcome and foster?

N e w f i e l d s o r new emphases of old f ie lds have come in to view several times during the last several years and will occur in the

future.

In the pas t , it was f a i r l y c l e a r as t o where the-antenna

ended and where the receiver began. Also it w a s f a i r l y clear as t o

where the antenna ended and the propagating medium began -- beyond

the f a r f i e ld . This has gradually chmged. Re-entry conditons and

burial of antennas (these are live antennas) in the ground mafie it necessary t o consider the pattern. and impedance of the antenna as a function of the plasma and earth which are i n t he nea r f i e ld . High

altitude operation at even low power leve ls cause plasma breakdown

which again interacts with the antenna. Electronically steered

antennas now made the antenna elements, the phase shifters and feed-

ing structure an integrated and interacting structure. A computer,

phase sh i f te r d r iver are a lso par t o f the an tenna system.

Signal processing antennas ( a s 0 c u e d " d a t a p r o c e s s b

antennas") have received a tremendous attention, most of it by antenna

Fople. In these arrays the emphasis. is on the processing behind the

elements with the g o g of improving antenna performance i n one o r more

' characterist ics - usually at the expense of others.* Example of these

' arrays are time-modulated arrays, self-steered arrays, multiplicative

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arrays, correlation errays.

The concepts can be applied t o s a t e l l i t e a r r a y s as well as to ground based arrays. Indications are that very large ground based

arrays - for instance - will not operate properly without the use of

these techniques due t o atmospheric decorrelation.

Some papers considering these techniques and applications are

going to other journals yet these are antenna system papers. Our charter i s f a i r ly exp l i c i t and states:

AKmcLE 11 Field of In te res t

Section 1. The field of interest of the Group ts experhenta l and

theare t ica l advances in electromagnetic theory and in the rad ia t ion ,

propagation, scattering and diffraction of radio waves, and of the

It can be defined as "you can't get something f o r nothin." *These seem to be an equivalent gain-bandwidth product in antennas.

devices, media ard f ields of application pertinent thereto such as antennas, plasmas, and radio astronomy systems.

Section 2. The f i e l d of in te res t of the Group may be enlarged, re-

duced or shifted moderately as the needs o f t h e occasion indicate

with the p-mvision tha t such revisions shall be processed as an admend-

ment t o this constitution.

A consti tutional revision may be made soon. Should it read:

antenna, antenna systems, plasmas and radio astronomy systems? Aren't

"astronomy systems" a special c lass of "antenna systems"?

It seems t o m e that,above all. we should consider the overall

question: Should these antenna systems become the province of

"systems" o r "antennas"?

Your comments are invited!

LETTERS TO 'PHE EDIWR

LETIF3 FROM JOEIN TIIPZE, EDITOR OF G-AP TRAn"jACpT0NS COhXXRKING RESULTS OF IWJSLETTEB SURVEY

"At this rrriting I have completed a year as edi tor of the Trans- actions and a l l s i x 1966 issues are i n press. In addition, the Special Issue on Pa r t i a l Coherence (Januzwy 1967), under the edi tor- ship of F. J. Zucker, AFCm has been submitted.

During this year I have genemJ2.y followed the book on accepting papers. That is, submitted papers required two favorable reviews from knowledgeable experts obtained with recommendations through a system of Associate Editors. This system t a k e s l i t t l e account of t he wishes of the reader o r of the opinion of the Editor.

M n g my tenure I have received complaints from the readership on the type of papers published, both persona3ly and in the Newsletter. I have therefore decided t o p o l l t h e group membership by means of a Newsletter questionnaire (Jme 1966) to determine our readers f ie ld of ac t iv i ty and techuical interest .

F r a y , the response to the quest ionnaire was disappointing with with only about 6.+ (262 replies) of the members responding. How- ever, I am t o l d t h a t this i s not unusual and t h a t t o o b t a i n a 3 0 % response one m u s t have a speciW mailing with a self-addressed stamped envelope and t ha t it must be sent to the business and not the home address. Also, inadvertently the addressee's label was attached t o the back of the questioimaire.

the replies e i ther steamed o f f o r blacked of f the addressee label. Neve-ss, I have no reason to be l i eve t ha t t h i s sample is not representative. A f t e r t he first hundred rep l ies , the t a l l i es qu icMy approached the f i na l asymptote.

The questionnaire was intended t o be anonymous and about % of

The f i r s t two questions were re la t ive ly simple and w e r e with the results: ,

Q-1. "I work principaJly in the following f ields" -

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