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Патент USA US2126295

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Aug“. 9,1938;
2,126,295
w. H. WARREN
ANTENNA SYSTEM
Filed Feb. 21, 1935
2 Sheets-Sheet 1
FIG. /
TL
'
‘
V
“
‘
7/7/1211
ANTENNAS
OTHER ‘
‘FIG. 3
Y‘ ‘
2
‘RT
RT
TL
72/.
A
TL’ ,EZLI AZ/Mnw/m
r
‘
~
INVENTOR '
WH. WARREN
- ATTOB/VEV
I
2,126,295
‘W. H. WARREN
ANTENNA SYSTEM‘
Filed Feb. 21, 1935
2 Sheets-She‘et 2
FIG. 4
COUPLING DEV/CE
lNl/EN TOR
'W._ H. WARREN
ATTORNEY
Patented Aug. 9,‘ v1938
2,126,295
UNITED STATES PATENT ()FFICE
2,126,295
ANTENNA SYSTEM
William H. Warren, New York, N. Y., assignor to
Western Electric Company, Incorporated, New
York, N. Y., a corporation of New York
Application February 21, 1935,’ Serial No. I7,501
In France April 25, 1934
15 Claims. (01. 250-11)
The present invention relates to improvements
in antenna systems, and more particularly in sys
tems comprising a plurality of directional anten
nas or antenna arrays.
Heretofore, in long distance broadcasting of
news and in certain transcontinental transmis
sions, it has been necessary to provide several di
rectional systems directed in different directions,
these systems being supplied simultaneously with
10 energy modulated in the same manner at least for
high frequency. Also each directional system has
been ordinarily associated with a separate radio
transmitter.
One object of this invention is to transmit or
receive energy in several predetermined directions
utilizing a single aerial system.
Another object of the present invention is to
.transmit, efficiently, energy in several directions
with a minimum amount of apparatus.
Still another object of this invention is to radi
ate a maximum amount of the energy supplied
‘by a transmitter to a radiating system.
According to this invention a plurality of direc
tional arrays, preferably aperiodic, is provided,
each of the arrays serving to establish directive
2
communications in different directions and said
arrays being fed by a common high frequency
feeding system on which one or several frequency
bands may be transmitted. The several direc
30 tional arrays are associated either in series or in
parallel or in combined grouping, with the trans
mission system, the arrangement being prefer
ably such that a predetermined quantity of energy
is radiated by each antenna network.
The invention will be better understood by re
35
ferring to- the attached drawings on which like
reference characters denote elements of similar
function, and on which:
Fig. 1 represents a directional antenna of the
well-known “diamond” or “rhombic” type which
.is disclosed in the application of E. Bruce, Serial
No. 513,063, filed February 3, 1931;
Fig. 2 shows a series or tandem arrangement of
two such rhombic antennas;
Fig. 3 shows a parallel arrangement of two
rhombic antennas;
Fig. 4 shows a coupling arrangement which is
suitable for transmitting two large bands of fre
quencies and for associating a rhombic antenna
50 with a radio transmitter;
'
Fig. 5 shows the combination of a rhombic an
tenna and another antenna arranged to obtain a
polarized radiation;
Fig. 6 shows an arrangement comprising a
1.5.5 rhombic antenna and an inverted V of the type
disclosed in Patent 1,899,410, E. Bruce, February
28, 1933;
Fig. '7 represents a tandem ‘arrangement of V
antennas.
It is well-known that one of the properties of
the rhombic antenna is its faculty of functioning
efficiently for a considerable band of frequencies.
This property, however, cannot be entirely utilized
when the antenna is rendered unidirectional by
means of a re?ector because a re?ector which 10
would be suitably placed for a "given frequency
would not be suitably positioned for another fre
quency. In order to preserve the multi-frequency
characteristic of the rhombic antenna and at the
same time effect unilateral operation, the antenna 15
‘is ‘designed to have the same characteristic im
pedance as the feeding system and an absorbing
line is connected to the distant end of the an
tenna, the characteristic impedance of the ab
sorbing line being approximately equal to that of
the antenna, whereby re?ection of non-radiated
energy is eliminated.
In such an arrangement
about half the total energy supplied to the feeding
system and antenna is lost in the absorbing trans
mission line.
In accordance with this invention the energy
feeding the absorbing line and otherwise lost is
utilized to energize a second preferably directive
antenna, this antenna being directed either in the
same direction as the ?rst antenna or in a diner
30
lent direction. Alternately, this energy otherwise
lost may before or after passage through a suit
able recti?er system be employed for metering the‘
power radiated.
Referring to the drawings the system of the 35
prior art illustrated by Fig. 1 comprises a radi
ating transmitter RT feeding a rhombic antenna
A by means of a transmission line TL of any
suitable type, such as a coaxial line or a line com
prising parallel wires. An absorbing transmission
line 'I‘La, is connected to the distant end of the
‘antenna A. Assuming that the loss in the trans
mission line TL is negligible, 50% of the energy
supplied by the radio transmitter RT is radiated
by the antenna A while the remaining 50% is
dissipated in the absorbing transmission line TLa,
the loss in the terminating line TLa being ap
proximately 3 decibels.
Instead of dissipating -
50% of the energy in the absorbing transmission
line, this energy or a part thereof is, in accordance 50
with this invention, employed to feed a second
antenna, as illustrated by Fig. 2.
In Fig. 2, RT designates a radio transmitter, TL
a transmission line of any suitable type and A a
rhombic antenna whose far end is connected by 55
2
2,126,295
transmission line TL’ to a second antenna A’, at
the distant end of which isplaced an absorbing
transmission line 'I'La. A coupling device CD
such as illustrated by Fig. 4 is included in the line
TL. Arrows l and 2 indicate respectively the
desired direction of operation for antennas A
and A’. In an actual case, the absorbing trans
mission line ‘11a was formed of two galvanized
iron wires 480 meters long and having diameters
centimeters between centers. To secure the same
attenuation with shorter lines the wires may be
formed of certain suitable alloys. 7
_
In the system of Fig. 2, if the losses in the
transmission lines TL are ignored, 50% of the
power supplied by the radio transmitter RT is
radiated by the transmitter A, 25% of the power
is radiated by the transmitter A’, assuming that
the losses in the transmission line TL’- are-negli
gible and 25% of the energy is dissipated in the
absorbing transmission line 'I'La. It will thus
clearly be seen that‘ a portion of the’energy
otherwise dissipated maybe advantageously’ em
ployed to drive another antenna, this'antenna
being'preferably provided with means for pre
reflection' losses.
'
'
'
V
Fig. 3 illustrates'two rhombic antennas A and
A’ connected in parallel. A radio transmitter
RT feeds a transmission line TL of any suitable
type, this line being terminated by’ branch lines
TL’ and TL" which feed the antennas A and A’
in parallel. Antennas Aand A’ terminate, re
spectively, in absorbing transmission’ lines 'I‘La
and TLa’.
gain of the second antenna will be, in view of
the energy received by the system, 3 decibels less
than that achieved by the ?rst antenna, the gain C21
being about 12 decibels over the dipole. Each
successive antenna will approximately lose 3 dec
ibels in e?iciency with respect to the preceding
antenna. In the case of four antennas con
They were spaced at.20v _ nected in tandem, the last antenna will still give
10 of 2 to 3 millimeters.
venting
sides four wave-lengths long, a gain of 15 dec
ibels over an ordinary dipole is realized. The
.
V‘
The distribution of " energy in the system of
Fig. 3 is as follows: 25% of the energy supplied
by radio transmitter RT is radiated by each of
antennas A and A’, and 25% is absorbed by each
of the lines 'I'La'and TLaL’I Comparing the tan
40 dem arrangement of Fig. 2 to the parallel ar
rangement of Fig; 3 it will be seen that in the
case of a tandem. connection only a'small loss is
sustained since there is only one dissipating line.
Other advantages’ of ‘the tandem array over the
45 parallel array are that a simple transmission sys
tem is employed and'the impedance in which
the radio transmitter RT discharges is approxi
mately the same whatever the number of an
tennas fed. It should be noted that in the case
50 of the parallel system, ‘special precautions must
be taken to properly terminate line TL for e?i
cient operation over a band of frequencies.
To
insure this the two auxiliary transmission lines
TL’ and TL" may be extended to the radio
transmitter RT 'and connected in parallel at
the output terminalsnof the power amplifying
unit.
'
The tandem array. of Fig. 2 permits the aperi
odic' characteristicfaswell as the unidirectional
60 property, of each antenna to be retained so that
one antenna may be directed in a certain direc
tion while another is directed in a different direc
tion. Also a de?nite’ quantity of energy may be
successively‘ brought to the various antennas con
nected in tandem, a small part of this energy
supplied ?nally arriving at the absorbing circuit
whose function is to render the system electri
cally long and to prevent re?ection losses. By
aligning groups of these antennas at various
points increased directional propagation may be
realized in diiferent directions,
'
Expressed on a transmission basis, the‘?rst
v‘antenna. is equivalent’in ef?ciency to a single iso
lated rhombic antenna of the same dimension
and, in the case of a rhornbic antenna having
about 6 decibels more than a dipole.
Attenua
tors and other devices used in high frequency
transmission circuits may be employed in the
system for adjusting the amount of energy radi
ated by each antenna as desired. Thus, in the
case of directional antennas directed in diverse
directions the quantity of energy radiated by
each antenna may be regulated in accordance
with the distance to be covered by the various
transmissions.
Fig‘. ‘ajsho'wsf a coupling device permitting a
rhombic antenna to be associated with a coaxial
or concentric transmission'line TL. The antenna
is connected to the line conductors Li and L2
which may be shunted by a preferably adjustable
tuningcondenser C... The line conductors L1 and
L are connected through coupling condensers C
to two impedance reducing transformers T1 and
T2 connected in parallel. These transformers
20
25/
are'constructed so as to have a unity coe?icient 30
of coupling between the primary and secondary
windings. For this purpose the secondary wind
ings may each be formed by a certain number of
spirals arranged in parallel, these spirals taking
up about the same space as the primary winding. '
The primary windings P1 and P2 are connected to
the transmission line TL through coupling con
densers C1 and C2. In Fig. 4 a terminal of each
primary winding is connected to ground since
one of the conductorsof the transmission line TL
is'connected to ground. "
'
The transformers T1 and T2 transmit different
frequency bands. In' a particular installation
transformer T1 was designed to transmit fre
quencies included between 4,500 kilocycles per
second and‘ 12,000 'kilocycles per second, and
transformer T2 to transmit the frequency band
extending from 12,000 kilocycles per second to
approximately 21,000 kilocycles per second. The
attenuation was substantially constant for fre
quencies between 9,000 and 14,000 kilocycles per
second. It may be added that in constructing
the antenna care‘ must be taken to avoid any
irregularity, which would destroy the uniform
character of the characteristic impedance. For
example, the insulators should be small and the
wires should be of uniform dimensions and un
associated with conducting members such as the
metal ?xtures.
'
' The invention may be employed in various 60
arrays and systems as, for example, the systems
illustrated by Figs. 5, 6 and 7. Referring particu
larly to Fig. 5, the transmission line TL" feeds
through transformer T a transmission line TL
which terminates in a transmitting antenna A’
of any type. This arrangement insures the use
of energy which would otherwise be lost and
which can be radiated by a directional or non
directional antenna. The phases of the currents
of A and A’ may be adjusted to obtain elliptically 70
polarized waves.
7
In Fig. 6 the antenna A’ is a directive V an
tenna array comprising a plurality of V antenna
elements V1, V2, V3, V4, connected to the auxiliary
transmission line TL”. The V antennas V1, V2, 75
3
2,126,295
V3, Vi are terminated, respectively, at their far
ends by suitable resistances R1, R2, R3 and R4,,
which render the V antennas unilateral. These
resistances may be directly connected to earth or,
if the earth is not well de?ned, to the middle
of, rhombic antennas connected in tandem, the
?rst of which is connected to said transmitter
and the last of which is terminated in its charac
teristic impedance.
4. In a radio system, a transmitter, a plurality
point of horizontal half wave-length counters of rhombic antennas arranged in tandem, the
poises. Obviously, the absorption resistances ?rst antenna being connected to said transmitter
terminating the V antennas may be replaced by
radiating elements. The direction of maximum
10 propagation in a horizontal plane of the rhombic
antenna and of the V antenna array coincide,
as indicated by arrows 3 and 4.
,
and the last being terminated in its characteristic
impedance, said last antenna and the intermedi
ateantennas each having an impedance equal to
the characteristic impedance of the preceding
antenna.
5. In a radio system, a transmitter, a plurality
Fig. 7 illustrates a tandem arrangement of two
V antenna arrays. In the system of this ?gure of similar ‘rhombic antennas connected in
tandem, the ?rst of which is connected to said 15
15 the radio transmitter RT feeds a transmission
line TL to which are connected at points spaced transmitter and the last of which is terminated
a half wave-length V antennas V1, V2, V3 and Vi in its characteristic impedance, at least two of
the antennas being oriented for propagation in
constituting an array. The far ends of these V
antennas are connected to another transmission different horizontal directions.
6. In a radio system, a transmitter, a rhombic 20
20 line TL’ at points spaced a half wave-length.
antenna
connected thereto, each side element of
Transmission line TL’, which may be of any
length, supplies an array similar to that which said antenna being a half wave-length longer
than the projection of said element on the path
has just been described and comprising V an
tennas V1’, V2’, V3’ and V4’. The far ends of of maximum wave propagation, substantially, a
second antenna having an impedance equal to 25
25 these V antennas are terminated in absorbing
the characteristic impedance of said ?rst an
resistances connected to ground or to counter
tenna, said second antenna being connected to
poises such as those illustrated by Fig. 6. Be
tween the two groups of antennas A and A’, Fig. said ?rst antenna.
7. A radio system, a transmitter, a rhombic an
'7, impedance networks may be provided, such as
tenna connected thereto, each side element of 30
?lters, for causing the antenna A’ to radiate dif
ferent frequencies from those of the antenna A. said antenna being a half wave-length longer
The major directive lobes of the antennas A and than the projection of said element on the path
of maximum wave propagation, substantially, a
A’ may be similarly or differently directed.
second antenna connected thereto and oriented
It may be desirable to radiate different quanti
to radiate waves polarized differently from the
ties
of
energy
in
speci?ed
directions,
utilizing
35
arrays connected in tandem or parallel. In the waves radiated by said rhombic antenna.
8. In a radio system, a rhombic antenna con
tandem arrangement the desired division between
the power radiated in the several directions may nected to a V antenna, said V antenna constitut
ing a means for rendering the rhombic antenna
be easily controlled within certain limits by prop
40
erly orienting the different arrays since, as already unilateral.
pointed out, the successive arrays radiate gradu
ally diminishing amounts of energy. In the par
allel arrangement, the energy is divided according
to the law of shunted circuits and equal amounts
of energy may be radiated in the speci?ed direc
tions. It is clear that, in accordance with this
invention, a single radiating system may be used
for multi-channel and multi-directional opera
tion, whereby for example, communication may
be realized between a single transmitter and a
certain number of receiving stations, any one of
which may be adapted to receive one or more of
the frequencies transmitted by the central radio
transmitting station.
Although the invention has been described in
connection with certain speci?c embodiments, it
is to be understood that it is not to be limited
to such embodiments. Obviously, different tan
dem or parallel arrangements, or combinations of
such arrangements, arranged either for transmit
ting or receiving, may be satisfactorily employed
without exceeding the scope of the invention.
What is claimed is:
1. In a radio system, a transmitter, a plurality
of directive antennas, said transmitter being con
nected directly to one antenna and only through
said antenna to the remaining antenna or anten
nas, and said antennas being oriented for e?ective
operation in different directions.
2. In a radio system, a transmitter, a plurality
of unilateral antennas connected in tandem and
to said transmitter, said antennas being oriented
for propagating energy in different horizontal
directions.
75
3. In a radio system, a transmitter, a plurality
9. In a radio system, a transmitter, an antenna
array connected thereto and comprising a uni
directional antenna oriented for maximum radia
tion in a given direction, a second array con
nected to said ?rst array and comprising unidi 45
rectional antennas oriented for maximum radia
tion in a single given direction, the frequencies of
operation for said arrays being different.
10. In a radio system, a transmitter, a plurality
of antenna arrays each comprising V antennas,
each element of said V antennas being approxi
mately a half wave-length longer than the pro~
jection of said element on the path of maximum
propagation, said ?rst antenna array being con
nected to said transmitter and. second array be 55
ing connected to said ?rst array.
11. In a radio system, a transmitter, a plural
ity of antenna arrays each comprising V anten~
nas, each element of said V antennas being ap
proximately a half wave-length longer than the
projection of said element on the path of maxi
mum propagation, said arrays being connected.
in tandem and each positioned for operation in a
desired direction, and said transmitter being con
nected to the V antennas constituting one of the
end arrays.
12. In a radio system, a ?rst antenna system,
a second antenna system, a translation device
connected through the ?rst system to the second
system, said second system constituting means 70
for rendering the ?rst system uni-directional.
13. In a radio system, a ?rst antenna compris
ing a pair of V-shaped elements having their
directions of maximum radiant action super
imposed, a second antenna, a translation device 75
2,126,295
connected through the ?rst antenna to the sec
ond antenna, said second antenna having an in
put impedance equal to the characteristic imped
ance of the ?rst antenna.
;
14. In a radio system, a ?rst antenna arranged
for operation over one frequency band, a second
antenna system arranged for operation over
another frequency band, a translation device con
nected through the ?rst system to the second
10 system, said second system having an input im
pedance suitable for rendering the ?rst system
unidirectional, an impedance connected to the
second system for rendering said system uni
directional, and coupling means included between
15 said device and said antennas, said coupling
means comprising a transformer for passing one
and a transformer for passing the other of said
bands with the same attenuation.
15. In a radio system, a plurality of directive
antenna systems each oriented for operation in
a desired direction and each comprising a pair of
V-shaped antenna elements, each element com
prising two conductors, a translation device, said
device being connected between and in series
with the V-shaped elements of each antenna 1O
system, the conductors of each system having
their directions of maximum radiant action su
perimposed and aligned with the desired direction
of action for the system.
WILLIAM H. WARREN. 15
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