550:
441:
398:
55:
1555:. Grating lobes are a source of disadvantages in both transmission and reception. In fact, in transmission, they can lead to radiation in unwanted directions, while, in reception, they can be a source of ambiguity since the desired signal entering the mainlobe region could be strongly disturbed by other signals (unwanted interfering signals) entering the regions of the various grating lobes. Therefore, in periodic arrays, the spacing between adjacent radiators must not exceed a specific value to prevent the appearance of grating lobes (in the visible space)
357:
468:
530:
376:
480:
569:
453:
422:
126:) to reduce the power radiated in other directions. Similarly, when used for receiving, the separate radio frequency currents from the individual antennas combine in the receiver with the correct phase relationship to enhance signals received from the desired directions and cancel signals from undesired directions. More sophisticated array antennas may have multiple transmitter or receiver modules, each connected to a separate antenna element or group of elements.
31:
510:
495:
305:) reducing the power radiated in that direction. Similarly, when receiving, the oscillating currents received by the separate antennas from radio waves received from desired directions are in phase and when combined in the receiver reinforce each other, while currents from radio waves received from other directions are out of phase and when combined in the receiver cancel each other.
750:
841:
1833:
the subject matters of matching and efficiency are involved, especially in the case of an antenna array of a mobile device (see chapter 10 of ), since, in this case, the surroundings of the antenna array influence its behavior, and vary over time. Suitable matching metrics and efficiency metrics take into account the worst possible excitations.
1825:
excitation received by each element (during emission) is also well chosen, it is possible to synthesize a single-port array having a radiation pattern that closely approximates a specified pattern. Many methods have been developed for array pattern synthesis. Additional issues to be considered are matching, radiation efficiency and bandwidth.
785:(AESA) – A phased array in which each antenna element has its own transmitter and/or receiver module, controlled by a central computer. This second generation phased array technology can radiate multiple beams at multiple frequencies simultaneously, and is mostly used in sophisticated military radars.
1828:
The design of an electronically steerable antenna array is different, because the phasing of each element can be varied, and possibly also the relative amplitude for each element. Here, the antenna array has multiple ports, so that the subject matters of matching and efficiency are more involved than
1824:
In an antenna array providing a fixed radiation pattern, we may consider that the feed network is a part of the antenna array. Thus, the antenna array has a single port. Narrow beams can be formed, provided the phasing of each element of the array is appropriate. If, in addition, the amplitude of the
882:
or Yagi antenna – this endfire array consists of multiple half-wave dipole elements in a line. It consists of a single driven element with multiple "director" parasitic elements in the direction of radiation, and usually a single "reflector" parasitic element behind it. They are widely used on the
723:– an outdoor wire shortwave transmitting antenna consisting of a planar array of wire dipoles suspended in front of a vertical reflector made of a "curtain" of parallel wires. Used on HF band as long distance transmitting antenna for shortwave broadcasting stations. May be steered as phased array.
1832:
An antenna array used for spatial diversity and/or spatial multiplexing (which are different types of MIMO radio communication) always has multiple ports. It is intended to receive independent excitations during emission, and to deliver more or less independent signals during reception. Here also,
1630:
As seen above, when the spacing is constant between adjacent radiators, the array factor is characterized by the presence of grating lobes. In the literature, it has been amply demonstrated that to destroy the array factor's periodicity, the same array's geometry must also be made aperiodic. It is
276:
A second technique is to use multiple antennas which are fed from the same transmitter or receiver; this is called an array antenna, or antenna array. For a transmitting antenna the electromagnetic wave received at any point is the vector sum of the electromagnetic waves from each of the antenna
1635:
with each other. Several methods have been developed to synthesize arrays in which also the positions represent further degrees of freedom (unknowns). There are both deterministic and probabilistic methodologies. Since the probabilistic theory of aperiodic arrays is a sufficiently systematised
874:, absorbing radio waves from the driven element and reradiating them with a different phase, to modify the radiation pattern of the antenna, increasing the power radiated in the desired direction. Since these have only one driven element they are often called "antennas" instead of "arrays".
549:
421:
918:
Let us consider a linear array whose elements are arranged along the x-axis of an orthogonal
Cartesian reference system. It is assumed that radiators have the same orientation and the same polarization of the electric field. Based on this, the array factor can be written as follows
320:, usually representing residual radiation in unwanted directions. The larger the width of the antenna and the greater the number of component antenna elements, the narrower the main lobe, and the higher the gain which can be achieved, and the smaller the sidelobes will be.
695:– a flat two-dimensional array of antennas. Since an array of omnidirectional antennas radiates two beams 180° apart broadside from both sides of the antenna, it is usually either mounted in front of a flat reflector, or is composed of directive antennas such as
49:
mounted in front of a wire screen reflector. The X-shaped dipoles give it a wide bandwidth to cover both the VHF (174–216 MHz) and UHF (470–700 MHz) TV bands. It has a gain of 5 dB VHF and 12 dB UHF and an 18 dB front-to-back
397:
200:
controlled by a computer. The beam of radio waves can be steered electronically to point instantly in any direction over a wide angle, without moving the antennas. However the term "phased array" is sometimes used to mean an ordinary array antenna.
765:– A planar array in which the beam can be steered electronically to point in any direction over a wide angle in front of the array, without physically moving the antenna. The current from the transmitter is fed to each component antenna through a
137:), that is a narrower beam of radio waves, than could be achieved by a single element. In general, the larger the number of individual antenna elements used, the higher the gain and the narrower the beam. Some antenna arrays (such as military
769:, controlled by a computer. By changing the relative phase of the feed currents, the beam can instantly be pointed in different directions. Widely used in military radars, this technique is rapidly spreading to civilian applications.
711:– a planar array of antennas, often half-wave dipoles fed in phase, in front of a flat reflector such as a metal plate or wire screen. This radiates a single beam of radio waves perpendicular (broadside) to the array. Used as UHF
836:(LPDA) – an endfire array consisting of many dipole driven elements in a line, with gradually increasing length. It acts as a high gain broadband antenna. Used as television reception antennas and for shortwave communication.
1812:
217:
of an antenna, the angular width of the beam of radio waves it emits, is proportional to the wavelength of the radio waves divided by the width of the antenna. Small antennas around one wavelength in size, such as
799:
which compensate for the varying path lengths, allowing the antenna to radiate a plane wave beam. Conformal antennas are often integrated into the curving skin of aircraft and missiles, to reduce aerodynamic
440:
529:
375:
629:– This is an array in which the individual component antennas are all "driven" – connected to the transmitter or receiver. The individual antennas, which are usually identical, often consist of single
1010:
1691:, are independent and identically distributed random variables whose support coincides with the whole array aperture. Consequently, the array factor is a stochastic process, whose mean is as follows
479:
568:
1147:
611:
is a linear array in which the direction of radiation is along the line of the antennas. The antennas must be fed with a phase difference equal to the separation of adjacent antennas.
1689:
1239:
1591:
1293:
818:– a receiving array that estimates the direction of arrival of the radio waves and electronically optimizes the radiation pattern adaptively to receive it, synthesizing a
1313:
1620:
1448:
1167:
1468:
1187:
1106:
1079:
1541:
1515:
1492:
1393:
1373:
1353:
1333:
1259:
1052:
1032:
1428:
467:
356:
1829:
in the single-port case. Moreover, matching and efficiency depend on the excitation, except when the interactions between the antennas can be ignored.
1697:
452:
434:
420–450 MHz radar antenna for ballistic missile detection, Alaska. The two circular arrays are each composed of 2677 crossed dipole antennas.
323:
Arrays in which the antenna elements are fed in phase are broadside arrays; the main lobe is emitted perpendicular to the plane of the elements.
2272:
777:(PESA) – A phased array as described above, in which the antenna elements are fed from a single transmitter or receiver through phase shifters.
1970:
2227:
1917:
562:
of 180 crossed dipoles in Alaska which can transmit a 3.6 MW beam of 3–10 MHz radio waves into the ionosphere for research purposes
509:
494:
773:
1189:
being the zenith angle and azimuth angle, respectively. If the spacing between adjacent elements is constant, then it can be written that
1559:), the spacing between adjacent radiators must not exceed a specific value. For example, as seen previously, the first grating lobes for
346:
such an array can have the resolution of an antenna with a diameter equal to the distance between the antennas. In the technique called
265:
to change the direction of the radio waves, to focus the radio waves from a single low gain antenna into a beam. This type is called an
1842:
781:
749:
1900:
2008:
1873:
619:) which don't belong to either of these categories, in which the direction of radiation is at some other angle to the antenna axis.
347:
604:) of the radio waves is perpendicular to the plane of the antennas. To radiate perpendicularly, the antennas must be fed in phase.
592:
Most array antennas can be divided into two classes based on how the component antennas' axis relates to the radiation direction.
289:, a beam of radio waves traveling in a specific direction. In directions in which the waves from the individual antennas arrive
74:, the antenna radiated a vertical fan-shaped beam which could be swept horizontally across the airspace in front of the antenna.
795:– a two-dimensional phased array which is not flat, but conforms to some curved surface. The individual elements are driven by
2277:
924:
282:
2282:
655:– a broadside array consisting of multiple identical dipole antennas oriented vertically in a line. This is a high gain
153:
54:
2243:
Broydé, F.; Clavelier, E. (January 2022). "The
Radiation and Transducer Efficiencies of a Multiport Antenna Array".
141:
radars) are composed of thousands of individual antennas. Arrays can be used to achieve higher gain, to give path
2287:
1497:
Now, suppose that the excitation coefficients are positive real variables. In this case, always in the domain of
294:
119:
196:; a driven array antenna in which each individual element is connected to the transmitter or receiver through a
707:
668:
404:
302:
123:
35:
1636:
theory, with a strong general methodological basis, let us first concentrate on describing its peculiarities.
1241:, and the array is said to be periodic. The array is periodic both spatially (physically) and in the variable
1111:
350:(VLBI) dishes on separate continents have been linked, creating "array antennas" thousands of miles in size.
656:
651:
363:
231:
157:
115:
1622:. So, in this case, there are no problems since, in this way, the grating lobes are outside the interval .
156:
from specific directions, to steer the radio beam electronically to point in different directions, and for
810:
1643:
1108:(in meters) are the complex excitation coefficient and the position of the n-th radiator, respectively,
736:
175:
consists of a single driven element connected to the feedline, and other elements which are not, called
878:
862:– This is an endfire array which consist of multiple antenna elements in a line of which only one, the
849:
180:
2181:
2134:
2084:
2037:
1890:
1192:
853:
832:
520:
342:
are linked together into an antenna array, to achieve higher resolution. Using the technique called
327:
285:
the spherical waves from the individual antennas combine (superpose) in front of the array to create
219:
892:
888:
660:
246:
235:
59:
1562:
1264:
907:
in a line, with one driven loop and the others parasitic. Functions similarly to the Yagi antenna.
845:
727:
712:
664:
516:
343:
210:
39:
739:
with copper foil on the reverse side functioning as a reflector. The elements are fed through
687:
mounted collinearly on a mast. High gain omnidirectional radiation pattern with wide bandwidth.
2223:
2197:
2150:
2100:
2053:
2004:
1896:
1869:
1298:
867:
791:
684:
644:
500:
339:
309:
270:
250:
239:
176:
30:
1863:
1596:
1433:
1152:
683:
array – specialized vertical antenna used for television broadcasting consisting of multiple
2248:
2189:
2142:
2092:
2045:
1315:
being the wavelength, then the magnitude of the array factor has a period, in the domain of
636:
536:
388:
223:
142:
1453:
1172:
1084:
1057:
700:
675:
575:
540:
458:
335:
331:
87:
1520:
2185:
2138:
2088:
2041:
822:
in that direction. Like a phased array it consists of multiple identical elements with
1947:
1500:
1477:
1378:
1358:
1338:
1318:
1244:
1037:
1017:
884:
863:
631:
579:
381:
168:
99:
46:
43:
1398:
2266:
823:
804:
796:
766:
732:
719:
485:
367:
301:, with the peak of one wave coinciding with the valley of another, the waves cancel (
297:) to enhance the power radiated. In directions in which the individual waves arrive
278:
197:
111:
895:
bands as television antennas, shortwave communication antennas, and in radar arrays.
242:), which radiates radio waves in a narrow beam, two general techniques can be used:
904:
899:
757:
696:
640:
616:
559:
431:
412:
298:
262:
254:
227:
188:
150:
138:
130:
71:
622:
Array antennas can also be categorized by how the element antennas are arranged:
17:
1375:
is an auxiliary variable. In fact, from a physical point of view, the values of
866:, is connected to the transmitter or receiver, while the other elements, called
214:
134:
103:
2169:
2122:
2072:
2025:
488:
shortwave transmitting antenna, Austria. Wire dipoles suspended between towers
446:
Some of the crossed-dipole elements in the PAVE PAWS phased array antenna, left
114:
relationship. The radio waves radiated by each individual antenna combine and
1807:{\displaystyle E\left=\textstyle \int \limits _{-L/2}^{L/2}f(x)\,e^{jkxu}\,dx}
1631:
possible to act on the positions of the radiators so that these positions are
743:
made of copper foil. Used as UHF and satellite television receiving antennas.
286:
258:
91:
2201:
2193:
2154:
2146:
2104:
2096:
2057:
2049:
871:
840:
819:
740:
601:
428:
313:
2252:
415:
consists of 32 half-wave dipole antennas in front of a reflecting screen.
317:
290:
107:
2026:"The peak sidelobe of the phased array having randomly located elements"
2123:"A mathematical theory of antenna arrays with randomly spaced elements"
600:
is a one or two dimensional array in which the direction of radiation (
408:
122:) to enhance the power radiated in desired directions, and cancelling (
67:
1517:, the array factor magnitude has a main lobe with maximum value at
1494:
changes, the extent of the visible space also changes accordingly.
543:
made of a Y-shaped array of 27 dish antennas in
Socorro, New Mexico
312:
of such an antenna consists of a strong beam in one direction, the
277:
elements. If the currents are fed to the antennas with the proper
839:
748:
555:
63:
53:
29:
1395:
that are of interest for radiative purposes fall in the interval
146:
90:
which work together as a single antenna, to transmit or receive
391:. Collinear dipole arrays, radiating a flat, fan-shaped beam.
848:, an endfire parasitic array consisting of a combination of a
316:, plus a series of weaker beams at different angles called
2218:
Sibille, Alain; Oestges, Claude; Zanella, Alberto (2011).
1547:, several secondary lobes lower than the mainlobe, called
234:
which radiate radio waves over a wide angle. To create a
2245:
Excem
Research Papers in Electronics and Electromagnetics
1005:{\displaystyle F(u)=\sum _{n=1}^{N}I_{n}\,e^{jk\,x_{n}u}}
1918:"What is MIMO? Multiple Input Multiple Output Tutorial"
1729:
1474:. As shown further, if the definition of the variable
1700:
1646:
1599:
1565:
1523:
1503:
1480:
1456:
1436:
1401:
1381:
1361:
1341:
1321:
1301:
1267:
1247:
1195:
1175:
1155:
1114:
1087:
1060:
1040:
1020:
927:
1806:
1683:
1614:
1585:
1535:
1509:
1486:
1462:
1442:
1422:
1387:
1367:
1347:
1327:
1307:
1287:
1253:
1233:
1181:
1161:
1141:
1100:
1073:
1046:
1026:
1004:
110:that feed the power to the elements in a specific
171:all connected to the receiver or transmitter. A
149:) which increases communication reliability, to
2170:"Statistically designed density-tapered arrays"
870:, are not. The parasitic elements function as
1977:. Radio-electronics.com (Adrio Communications)
2174:IEEE Transactions on Antennas and Propagation
2127:IEEE Transactions on Antennas and Propagation
2030:IEEE Transactions on Antennas and Propagation
1924:. Radio-electronics.com (Adrio Communications
639:, but may also be composite antennas such as
163:The term antenna array most commonly means a
8:
2077:IRE Transactions on Antennas and Propagation
1941:
1939:
1661:
1647:
826:in the feed lines, controlled by a computer.
27:Set of multiple antennas which work together
753:Animation showing how a phased array works.
2213:
2211:
2168:Skolnik, M.; Sherman, J.; Ogg, F. (1964).
1430:, which is associated with the values of
473:Crossed-dipole FM radio broadcast antenna
1796:
1781:
1776:
1754:
1750:
1741:
1734:
1699:
1675:
1664:
1654:
1645:
1598:
1575:
1564:
1522:
1502:
1479:
1455:
1435:
1400:
1380:
1360:
1340:
1320:
1300:
1277:
1266:
1246:
1219:
1200:
1194:
1174:
1154:
1113:
1092:
1086:
1065:
1059:
1039:
1019:
991:
986:
979:
974:
968:
958:
947:
926:
1889:Graf, Rudolf F., ed. (1999). "Antenna".
1862:Carr, Joseph; Hippisley, George (2012).
1470:. In this case, the interval is called
1142:{\displaystyle u=\sin \theta \cos \phi }
703:antennas, to give a unidirectional beam.
66:, the Nebo-M. It consists of 175 folded
1854:
352:
273:is an example of this type of antenna.
1640:Suppose that the radiators positions,
578:used as a satellite tracking antenna,
503:array used for satellite communication
7:
2116:
2114:
1994:
1992:
774:Passive Electronically Scanned Array
179:. It is usually another name for a
129:An antenna array can achieve higher
98:) are usually connected to a single
2220:MIMO: From Theory to Implementation
2073:"Theory of unequally-spaced arrays"
1843:Total active reflection coefficient
1684:{\displaystyle \{x_{n}\}_{n=1}^{N}}
1034:is the number of antenna elements,
782:Active Electronically Scanned Array
461:VHF television broadcasting antenna
94:. The individual antennas (called
2001:Antennas and Radiowave Propagation
1865:Practical Antenna Handbook, 5th Ed
663:band as broadcasting antennas for
42:. This example consists of eight
34:A common type of array antenna, a
25:
348:Very Long Baseline Interferometry
167:consisting of multiple identical
86:) is a set of multiple connected
1892:Modern Dictionary of Electronics
567:
548:
528:
508:
493:
478:
466:
451:
439:
420:
396:
374:
355:
249:by large metal surfaces such as
58:Large planar array antenna of a
1355:. It is worth emphasising that
1234:{\displaystyle x_{n+1}-x_{n}=d}
615:There are also arrays (such as
326:The largest array antennas are
226:, don't have much directivity (
1773:
1767:
1718:
1712:
1417:
1402:
937:
931:
667:and base station antennas for
1:
2273:Radio frequency antenna types
1551:and mainlobe replicas called
1586:{\displaystyle d=\lambda /2}
1288:{\displaystyle d=\lambda /2}
903:– This consists of multiple
763:electronically scanned array
194:electronically scanned array
281:, due to the phenomenon of
62:Russian mobile air defense
2304:
1999:Collin, Robert E. (1985).
1946:Bevelacqua, Peter (2016).
669:land mobile two-way radios
293:, the waves add together (
120:interfering constructively
1971:"Smart Antennas Tutorial"
833:Log-periodic dipole array
295:constructive interference
124:interfering destructively
2194:10.1109/TAP.1964.1138239
2147:10.1109/TAP.1964.1138220
2097:10.1109/TAP.1962.1137952
2050:10.1109/TAP.1972.1140162
1975:Antennas and propagation
1922:Antennas and propagation
1820:Design of antenna arrays
1308:{\displaystyle \lambda }
303:destructive interference
245:One technique is to use
232:omnidirectional antennas
1615:{\displaystyle u=\pm 2}
1443:{\displaystyle \theta }
1162:{\displaystyle \theta }
685:crossed-dipole antennas
657:omnidirectional antenna
158:radio direction finding
2278:Microwave transmission
2253:10.5281/zenodo.5816837
2024:Steinberg, B. (1972).
1895:. Newnes. p. 29.
1808:
1763:
1685:
1616:
1587:
1537:
1511:
1488:
1464:
1444:
1424:
1389:
1369:
1349:
1329:
1309:
1289:
1255:
1235:
1183:
1163:
1143:
1102:
1075:
1048:
1028:
1006:
963:
857:
811:reconfigurable antenna
754:
413:World War II
220:quarter-wave monopoles
75:
51:
2071:Ishimaru, A. (1962).
1809:
1730:
1686:
1617:
1588:
1538:
1512:
1489:
1465:
1463:{\displaystyle \phi }
1445:
1425:
1390:
1370:
1350:
1330:
1310:
1290:
1256:
1236:
1184:
1182:{\displaystyle \phi }
1164:
1144:
1103:
1101:{\displaystyle x_{n}}
1076:
1074:{\displaystyle I_{n}}
1049:
1029:
1007:
943:
843:
752:
737:printed circuit board
330:used in the field of
328:radio interferometers
57:
33:
2283:Microwave technology
1950:. Antenna-theory.com
1698:
1644:
1597:
1563:
1557:in the visible space
1521:
1501:
1478:
1454:
1434:
1399:
1379:
1359:
1339:
1319:
1299:
1265:
1245:
1193:
1173:
1153:
1112:
1085:
1058:
1038:
1018:
925:
715:and radar antennas.
659:, often used in the
338:consisting of large
334:, in which multiple
251:parabolic reflectors
70:antennas. An early
2186:1964ITAP...12..408S
2139:1964ITAP...12..257L
2089:1962ITAP...10..691I
2042:1972ITAP...20..129S
1969:Poole, Ian (2016).
1916:Poole, Ian (2016).
1680:
1536:{\displaystyle u=0}
1054:is the wavenumber,
713:television antennas
665:television stations
236:directional antenna
118:, adding together (
1804:
1803:
1681:
1660:
1612:
1583:
1533:
1507:
1484:
1460:
1440:
1420:
1385:
1365:
1345:
1325:
1305:
1285:
1261:. For example, if
1251:
1231:
1179:
1159:
1139:
1098:
1071:
1044:
1024:
1002:
868:parasitic elements
858:
846:television antenna
755:
728:Microstrip antenna
645:turnstile antennas
411:radar used during
344:aperture synthesis
340:parabolic antennas
211:Rayleigh criterion
177:parasitic elements
76:
52:
40:television antenna
2229:978-0-12-382194-2
1633:not commensurable
1510:{\displaystyle u}
1487:{\displaystyle u}
1388:{\displaystyle u}
1368:{\displaystyle u}
1348:{\displaystyle 2}
1328:{\displaystyle u}
1254:{\displaystyle u}
1047:{\displaystyle k}
1027:{\displaystyle N}
637:half-wave dipoles
501:Turnstile antenna
310:radiation pattern
240:high gain antenna
224:half-wave dipoles
192:usually means an
18:Directional array
16:(Redirected from
2295:
2288:Antennas (radio)
2257:
2256:
2240:
2234:
2233:
2215:
2206:
2205:
2165:
2159:
2158:
2118:
2109:
2108:
2068:
2062:
2061:
2021:
2015:
2014:
1996:
1987:
1986:
1984:
1982:
1966:
1960:
1959:
1957:
1955:
1948:"Array Antennas"
1943:
1934:
1933:
1931:
1929:
1913:
1907:
1906:
1886:
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1879:
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1813:
1811:
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1725:
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1687:
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1679:
1674:
1659:
1658:
1626:Aperiodic Arrays
1621:
1619:
1618:
1613:
1592:
1590:
1589:
1584:
1579:
1542:
1540:
1539:
1534:
1516:
1514:
1513:
1508:
1493:
1491:
1490:
1485:
1469:
1467:
1466:
1461:
1449:
1447:
1446:
1441:
1429:
1427:
1426:
1423:{\displaystyle }
1421:
1394:
1392:
1391:
1386:
1374:
1372:
1371:
1366:
1354:
1352:
1351:
1346:
1334:
1332:
1331:
1326:
1314:
1312:
1311:
1306:
1294:
1292:
1291:
1286:
1281:
1260:
1258:
1257:
1252:
1240:
1238:
1237:
1232:
1224:
1223:
1211:
1210:
1188:
1186:
1185:
1180:
1168:
1166:
1165:
1160:
1148:
1146:
1145:
1140:
1107:
1105:
1104:
1099:
1097:
1096:
1080:
1078:
1077:
1072:
1070:
1069:
1053:
1051:
1050:
1045:
1033:
1031:
1030:
1025:
1011:
1009:
1008:
1003:
1001:
1000:
996:
995:
973:
972:
962:
957:
879:Yagi–Uda antenna
735:fabricated on a
708:Reflective array
576:helical antennas
571:
552:
537:Very Large Array
532:
517:microstrip array
512:
497:
482:
470:
455:
443:
424:
405:reflective array
400:
389:cell phone tower
378:
359:
336:radio telescopes
267:aperture antenna
181:Yagi–Uda antenna
36:reflective array
21:
2303:
2302:
2298:
2297:
2296:
2294:
2293:
2292:
2263:
2262:
2261:
2260:
2242:
2241:
2237:
2230:
2217:
2216:
2209:
2167:
2166:
2162:
2121:Lo, Y. (1964).
2120:
2119:
2112:
2070:
2069:
2065:
2023:
2022:
2018:
2011:
2003:. McGraw-Hill.
1998:
1997:
1990:
1980:
1978:
1968:
1967:
1963:
1953:
1951:
1945:
1944:
1937:
1927:
1925:
1915:
1914:
1910:
1905:. uah1PkxWeKYC.
1903:
1888:
1887:
1883:
1876:
1868:. McGraw-Hill.
1861:
1860:
1856:
1851:
1839:
1822:
1816:
1777:
1708:
1704:
1696:
1695:
1694:
1650:
1642:
1641:
1639:
1628:
1595:
1594:
1561:
1560:
1519:
1518:
1499:
1498:
1476:
1475:
1452:
1451:
1432:
1431:
1397:
1396:
1377:
1376:
1357:
1356:
1337:
1336:
1317:
1316:
1297:
1296:
1263:
1262:
1243:
1242:
1215:
1196:
1191:
1190:
1171:
1170:
1151:
1150:
1110:
1109:
1088:
1083:
1082:
1061:
1056:
1055:
1036:
1035:
1016:
1015:
987:
975:
964:
923:
922:
916:
914:Periodic Arrays
860:Parasitic array
792:Conformal array
652:Collinear array
598:broadside array
590:
583:
572:
563:
553:
544:
541:radio telescope
533:
524:
513:
504:
498:
489:
483:
474:
471:
462:
456:
447:
444:
435:
425:
416:
401:
392:
382:Sector antennas
379:
370:
364:collinear array
360:
332:radio astronomy
207:
173:parasitic array
169:driven elements
47:driven elements
28:
23:
22:
15:
12:
11:
5:
2301:
2299:
2291:
2290:
2285:
2280:
2275:
2265:
2264:
2259:
2258:
2235:
2228:
2207:
2180:(4): 408–417.
2160:
2133:(3): 257–268.
2110:
2083:(6): 691–702.
2063:
2036:(2): 129–136.
2016:
2009:
1988:
1961:
1935:
1908:
1902:978-0750698665
1901:
1881:
1874:
1853:
1852:
1850:
1847:
1846:
1845:
1838:
1835:
1821:
1818:
1802:
1799:
1793:
1790:
1787:
1784:
1780:
1775:
1772:
1769:
1766:
1761:
1757:
1753:
1748:
1744:
1740:
1737:
1733:
1728:
1724:
1720:
1717:
1714:
1711:
1707:
1703:
1678:
1673:
1670:
1667:
1663:
1657:
1653:
1649:
1627:
1624:
1611:
1608:
1605:
1602:
1582:
1578:
1574:
1571:
1568:
1532:
1529:
1526:
1506:
1483:
1459:
1439:
1419:
1416:
1413:
1410:
1407:
1404:
1384:
1364:
1344:
1324:
1304:
1284:
1280:
1276:
1273:
1270:
1250:
1230:
1227:
1222:
1218:
1214:
1209:
1206:
1203:
1199:
1178:
1158:
1138:
1135:
1132:
1129:
1126:
1123:
1120:
1117:
1095:
1091:
1068:
1064:
1043:
1023:
999:
994:
990:
985:
982:
978:
971:
967:
961:
956:
953:
950:
946:
942:
939:
936:
933:
930:
915:
912:
911:
910:
909:
908:
896:
864:driven element
837:
829:
828:
827:
824:phase shifters
816:adaptive array
801:
797:phase shifters
788:
787:
786:
778:
746:
745:
744:
733:patch antennas
731:– an array of
724:
704:
690:
689:
688:
676:Superturnstile
632:driven element
613:
612:
605:
589:
586:
585:
584:
580:Pleumeur-Bodou
574:Array of four
573:
566:
564:
554:
547:
545:
534:
527:
525:
514:
507:
505:
499:
492:
490:
484:
477:
475:
472:
465:
463:
457:
450:
448:
445:
438:
436:
426:
419:
417:
407:antenna of an
402:
395:
393:
380:
373:
371:
368:folded dipoles
361:
354:
271:parabolic dish
261:by dielectric
206:
203:
26:
24:
14:
13:
10:
9:
6:
4:
3:
2:
2300:
2289:
2286:
2284:
2281:
2279:
2276:
2274:
2271:
2270:
2268:
2254:
2250:
2246:
2239:
2236:
2231:
2225:
2221:
2214:
2212:
2208:
2203:
2199:
2195:
2191:
2187:
2183:
2179:
2175:
2171:
2164:
2161:
2156:
2152:
2148:
2144:
2140:
2136:
2132:
2128:
2124:
2117:
2115:
2111:
2106:
2102:
2098:
2094:
2090:
2086:
2082:
2078:
2074:
2067:
2064:
2059:
2055:
2051:
2047:
2043:
2039:
2035:
2031:
2027:
2020:
2017:
2012:
2010:0-07-011808-6
2006:
2002:
1995:
1993:
1989:
1976:
1972:
1965:
1962:
1949:
1942:
1940:
1936:
1923:
1919:
1912:
1909:
1904:
1898:
1894:
1893:
1885:
1882:
1877:
1875:9780071639590
1871:
1867:
1866:
1858:
1855:
1848:
1844:
1841:
1840:
1836:
1834:
1830:
1826:
1819:
1817:
1814:
1800:
1797:
1791:
1788:
1785:
1782:
1778:
1770:
1764:
1759:
1755:
1751:
1746:
1742:
1738:
1735:
1731:
1726:
1722:
1715:
1709:
1705:
1701:
1692:
1676:
1671:
1668:
1665:
1655:
1651:
1637:
1634:
1625:
1623:
1609:
1606:
1603:
1600:
1580:
1576:
1572:
1569:
1566:
1558:
1554:
1553:grating-lobes
1550:
1546:
1530:
1527:
1524:
1504:
1495:
1481:
1473:
1472:visible space
1457:
1437:
1414:
1411:
1408:
1405:
1382:
1362:
1342:
1322:
1302:
1282:
1278:
1274:
1271:
1268:
1248:
1228:
1225:
1220:
1216:
1212:
1207:
1204:
1201:
1197:
1176:
1156:
1136:
1133:
1130:
1127:
1124:
1121:
1118:
1115:
1093:
1089:
1066:
1062:
1041:
1021:
1012:
997:
992:
988:
983:
980:
976:
969:
965:
959:
954:
951:
948:
944:
940:
934:
928:
920:
913:
906:
905:loop antennas
902:
901:
897:
894:
890:
886:
881:
880:
876:
875:
873:
869:
865:
861:
855:
851:
847:
842:
838:
835:
834:
830:
825:
821:
817:
813:
812:
807:
806:
805:Smart antenna
802:
798:
794:
793:
789:
784:
783:
779:
776:
775:
771:
770:
768:
767:phase shifter
764:
760:
759:
751:
747:
742:
738:
734:
730:
729:
725:
722:
721:
720:Curtain array
717:
716:
714:
710:
709:
705:
702:
698:
694:
691:
686:
682:
678:
677:
673:
672:
670:
666:
662:
658:
654:
653:
649:
648:
646:
642:
641:Yagi antennas
638:
634:
633:
628:
625:
624:
623:
620:
618:
617:phased arrays
610:
609:endfire array
606:
603:
599:
595:
594:
593:
587:
581:
577:
570:
565:
561:
557:
551:
546:
542:
538:
531:
526:
522:
518:
511:
506:
502:
496:
491:
487:
486:Curtain array
481:
476:
469:
464:
460:
454:
449:
442:
437:
433:
430:
427:US Air Force
423:
418:
414:
410:
406:
403:108 MHz
399:
394:
390:
386:
383:
377:
372:
369:
365:
358:
353:
351:
349:
345:
341:
337:
333:
329:
324:
321:
319:
315:
311:
306:
304:
300:
296:
292:
288:
284:
280:
274:
272:
268:
264:
260:
256:
252:
248:
243:
241:
237:
233:
229:
225:
221:
216:
212:
204:
202:
199:
198:phase shifter
195:
191:
190:
184:
182:
178:
174:
170:
166:
161:
159:
155:
152:
148:
145:(also called
144:
140:
136:
132:
127:
125:
121:
117:
113:
109:
105:
101:
97:
93:
89:
85:
84:array antenna
81:
80:antenna array
73:
69:
65:
61:
56:
48:
45:
41:
37:
32:
19:
2244:
2238:
2222:. Elsevier.
2219:
2177:
2173:
2163:
2130:
2126:
2080:
2076:
2066:
2033:
2029:
2019:
2000:
1981:February 23,
1979:. Retrieved
1974:
1964:
1954:February 23,
1952:. Retrieved
1928:February 23,
1926:. Retrieved
1921:
1911:
1891:
1884:
1864:
1857:
1831:
1827:
1823:
1815:
1693:
1638:
1632:
1629:
1556:
1552:
1548:
1544:
1496:
1471:
1013:
921:
917:
900:Quad antenna
898:
877:
859:
854:log periodic
831:
815:
809:
803:
790:
780:
772:
762:
758:Phased array
756:
726:
718:
706:
693:Planar array
692:
680:
674:
650:
630:
627:Driven array
626:
621:
614:
608:
597:
591:
560:phased array
521:satellite TV
519:antenna for
432:phased array
385:(white bars)
384:
325:
322:
307:
299:out of phase
283:interference
275:
266:
244:
230:); they are
208:
193:
189:phased array
187:
185:
172:
165:driven array
164:
162:
154:interference
139:phased array
128:
95:
83:
79:
77:
72:phased array
1335:, equal to
635:s, such as
287:plane waves
215:directivity
135:directivity
104:transmitter
92:radio waves
2267:Categories
1849:References
872:resonators
844:A rooftop
741:striplines
523:reception.
259:refraction
247:reflection
2202:0096-1973
2155:0096-1973
2105:0096-1973
2058:0096-1973
1736:−
1732:∫
1607:±
1593:occur in
1573:λ
1549:sidelobes
1543:, called
1458:ϕ
1438:θ
1406:−
1303:λ
1275:λ
1213:−
1177:ϕ
1157:θ
1137:ϕ
1134:
1128:θ
1125:
945:∑
820:main lobe
602:main lobe
429:PAVE PAWS
318:sidelobes
314:main lobe
209:From the
205:Principle
143:diversity
116:superpose
108:feedlines
1837:See also
1545:mainlobe
582:, France
291:in phase
100:receiver
96:elements
88:antennas
2182:Bibcode
2135:Bibcode
2085:Bibcode
2038:Bibcode
1295:, with
1149:, with
856:antenna
701:helical
681:Batwing
459:Batwing
409:SCR-270
160:(RDF).
2226:
2200:
2153:
2103:
2056:
2007:
1899:
1872:
1014:where
891:, and
263:lenses
213:, the
151:cancel
68:dipole
50:ratio.
44:dipole
2247:(4).
800:drag.
588:Types
556:HAARP
515:Flat
279:phase
269:. A
257:, or
255:horns
112:phase
64:radar
2224:ISBN
2198:ISSN
2151:ISSN
2101:ISSN
2054:ISSN
2005:ISBN
1983:2017
1956:2017
1930:2017
1897:ISBN
1870:ISBN
1450:and
1169:and
1081:and
852:and
850:Yagi
697:Yagi
558:, a
539:, a
535:The
362:VHF
308:The
228:gain
222:and
147:MIMO
131:gain
82:(or
38:UHF
2249:doi
2190:doi
2143:doi
2093:doi
2046:doi
1131:cos
1122:sin
893:UHF
889:VHF
814:or
761:or
699:or
679:or
661:VHF
643:or
607:An
387:on
366:of
253:or
106:by
102:or
78:An
60:VHF
2269::
2210:^
2196:.
2188:.
2178:12
2176:.
2172:.
2149:.
2141:.
2131:12
2129:.
2125:.
2113:^
2099:.
2091:.
2081:10
2079:.
2075:.
2052:.
2044:.
2034:20
2032:.
2028:.
1991:^
1973:.
1938:^
1920:.
887:,
885:HF
808:,
671:.
647:.
596:A
186:A
183:.
2255:.
2251::
2232:.
2204:.
2192::
2184::
2157:.
2145::
2137::
2107:.
2095::
2087::
2060:.
2048::
2040::
2013:.
1985:.
1958:.
1932:.
1878:.
1801:x
1798:d
1792:u
1789:x
1786:k
1783:j
1779:e
1774:)
1771:x
1768:(
1765:f
1760:2
1756:/
1752:L
1747:2
1743:/
1739:L
1727:=
1723:]
1719:)
1716:u
1713:(
1710:F
1706:[
1702:E
1677:N
1672:1
1669:=
1666:n
1662:}
1656:n
1652:x
1648:{
1610:2
1604:=
1601:u
1581:2
1577:/
1570:=
1567:d
1531:0
1528:=
1525:u
1505:u
1482:u
1418:]
1415:1
1412:,
1409:1
1403:[
1383:u
1363:u
1343:2
1323:u
1283:2
1279:/
1272:=
1269:d
1249:u
1229:d
1226:=
1221:n
1217:x
1208:1
1205:+
1202:n
1198:x
1119:=
1116:u
1094:n
1090:x
1067:n
1063:I
1042:k
1022:N
998:u
993:n
989:x
984:k
981:j
977:e
970:n
966:I
960:N
955:1
952:=
949:n
941:=
938:)
935:u
932:(
929:F
238:(
133:(
20:)
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
