Antenna Pola Radiasi - Revision history

Unknown user: /* Referensi */

2022-11-23T02:22:42Z

Referensi

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	* https://www.radartutorial.eu/06.antennas/Antenna%20Pattern.en.html		* https://www.radartutorial.eu/06.antennas/Antenna%20Pattern.en.html


			==Pranala Menarik==

			* [[5G]]

Unknown user: /* 3D Antenna Patterns */

2022-11-23T02:22:25Z

3D Antenna Patterns

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	radiant lines adalah tanda sudut elevasi, di sini dalam half-degree-steps. Skala sumbu x dan sumbu y yang tidak sama (banyak-nya feet versus banyak-nya mil laut) menyebabkan jarak non-linier antara tanda sudut elevasi. Ketinggian ditampilkan sebagai pola kisi linier. Kisi kedua (bertitik) berorientasi pada kelengkungan bumi.		radiant lines adalah tanda sudut elevasi, di sini dalam half-degree-steps. Skala sumbu x dan sumbu y yang tidak sama (banyak-nya feet versus banyak-nya mil laut) menyebabkan jarak non-linier antara tanda sudut elevasi. Ketinggian ditampilkan sebagai pola kisi linier. Kisi kedua (bertitik) berorientasi pada kelengkungan bumi.

	==3D Antenna ~~Patterns~~==		==Pola 3D Antenna==

	~~[[File:Feedhorn.png\|center\|300px\|thumb]]~~		Pola antena tiga dimensi feedhorn,

	~~Three-dimensional antenna pattern of a~~ feedhorn,

	~~Figure 4: Three-dimensional antenna pattern of a feed horn~~

	Antenna diagrams in three-dimensional representation are mostly computer-generated images. Mostly they are generated by simulation programs whose values are astonishingly close to a real measured diagram. To generate a real measured diagram means an immense measuring effort since each pixel of the image represents its own measured value.

	Most antenna measurement programs, therefore, choose a compromise for this representation. Only a vertical and a horizontal section through the antenna diagram are available as real measured values. All other pixels are calculated by multiplying the entire measurement curve of the vertical diagram by a single measurement value of the horizontal diagram. The computing power required is enormous. With the exception of a pleasing representation in presentations, the benefit is doubtful, since no new information can be gained from this representation compared to the two individual diagrams (horizontal and vertical antenna diagram). On the contrary: especially in the peripheral zones, a diagram generated with this compromise should deviate considerably from the reality.

	~~Also, 3D diagrams can be represented in Cartesian as well as in polar coordinates.~~


			[[File:Feedhorn.png\|center\|300px\|thumb\|Figure 4: Three-dimensional antenna pattern of a feed horn]]

			Diagram antena dalam representasi tiga dimensi sebagian besar adalah gambar yang dihasilkan komputer. Sebagian besar mereka dihasilkan oleh program simulasi yang nilainya sangat dekat dengan diagram hasil pengukuran yang sebenarnya. Untuk menghasilkan diagram hasil pengukuran yang sebenarnya berarti upaya pengukuran yang sangat luarbiasa karena setiap piksel gambar mewakili nilai terukurnya sendiri.

			Oleh karena itu, sebagian besar program pengukuran antena memilih kompromi untuk representasi ini. Hanya bagian vertikal dan horizontal melalui diagram antena yang tersedia sebagai nilai hasil pengukuran yang sebenarnya. Semua piksel lainnya dihitung dengan mengalikan seluruh kurva pengukuran diagram vertikal dengan satu nilai pengukuran diagram horizontal. Daya komputasi yang dibutuhkan sangat besar. Dengan pengecualian representasi yang untuk menyenangkan dalam presentasi, manfaatnya diragukan, karena tidak ada informasi baru yang dapat diperoleh dari representasi ini dibandingkan dengan dua diagram individu (diagram antena horizontal dan vertikal). Sebaliknya: terutama di zona periferal, diagram yang dihasilkan dengan kompromi ini biasanya akan jauh menyimpang dari kenyataan.

			Juga, diagram 3D dapat direpresentasikan dalam Cartesian serta koordinat polar.

	==Referensi==		==Referensi==

	* https://www.radartutorial.eu/06.antennas/Antenna%20Pattern.en.html		* https://www.radartutorial.eu/06.antennas/Antenna%20Pattern.en.html

Unknown user: /* Vertical Radiation Pattern */

2022-11-23T02:16:07Z

Vertical Radiation Pattern

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	==Vertical Radiation Pattern==		==Vertical Radiation Pattern==

	~~The shape of the vertical pattern is a vertical cross cut of the three-dimensional graph~~. ~~In the shown~~ polar ~~diagram~~ (~~a quarter part of the circle~~) ~~with the antenna site as the origin~~, ~~the~~ x~~-axis is the~~ radar ~~range~~, ~~and the~~ y~~-axis the aims height~~. ~~One of the antenna measurement techniques is the~~ Sun-Strobe-Recording ~~using~~ RASS-S, ~~a measurement tool of~~ Intersoft Electronics. ~~The~~ RASS-S (Radar Analysis Support System for Sites) ~~is a~~ radar ~~manufacturer-independent system for evaluating the different elements of~~ radar ~~by connecting to signals which are already available and this under operational conditions~~.		Bentuk pola vertikal merupakan potongan melintang vertikal dari grafik tiga dimensi. Dalam diagram polar yang ditunjukkan (seperempat bagian lingkaran) dengan situs antena sebagai asal, sumbu x adalah jangkauan radar, dan sumbu y adalah ketinggian tujuan. Salah satu teknik pengukuran antena adalah Sun-Strobe-Recording menggunakan RASS-S, alat ukur dari Intersoft Electronics. RASS-S (Radar Analysis Support System for Sites) adalah sistem independen pabrikan radar untuk mengevaluasi berbagai elemen radar dengan menghubungkan ke sinyal yang sudah tersedia dan ini dalam kondisi operasional.

	[[File:Vertical.png\|center\|300px\|thumb]]		[[File:Vertical.png\|center\|300px\|thumb\|Figure 3: Vertical antenna pattern with cosecant squared characteristic]]
	Figure 3: Vertical antenna pattern with cosecant squared characteristic

	~~In the shown Figure~~ 3, ~~the measurement units are nautical miles as range~~, ~~and~~ feet ~~as height~~. ~~Both measurement units are still used in Air- Traffic- Management by historical reasons~~. ~~These units are of secondarily meaning only because the plotted quantity of radiation pattern is defined as a relative level~~. ~~This means the~~ boresight ~~axis has got the value of the~~ (~~theoretical~~) ~~maximum range calculated with the help of the~~ Radar ~~Equation~~. ~~The shape of the~~ plot ~~provides the required information only~~! ~~To get absolute values you need a second~~ plot, ~~measured under the same conditions~~. ~~These two plots you can compare and then you achieve over increasing or decreasing the antennas performance~~.		Dalam Gambar 3 yang ditunjukkan, satuan pengukuran adalah mil laut sebagai jangkauan, dan feet sebagai ketinggian. Kedua satuan pengukuran tersebut masih digunakan dalam Manajemen Lalu Lintas Udara karena alasan historis. Satuan ini memiliki arti sekunder hanya karena jumlah pola radiasi yang diplot didefinisikan sebagai tingkat relatif. Ini berarti sumbu boresight telah mendapatkan nilai jangkauan maksimum (teoritis) yang dihitung dengan bantuan Persamaan Radar. Bentuk plot hanya memberikan informasi yang diperlukan! Untuk mendapatkan nilai absolut, Anda memerlukan plot kedua, yang diukur dalam kondisi yang sama. Kedua plot ini dapat Anda bandingkan dan kemudian Anda mencapai peningkatan atau penurunan kinerja antena.

	~~The~~ radiant lines ~~are marks of elevation angles~~, ~~here in~~ half-degree-steps. ~~The unequal scales of the~~ x~~-axis and the~~ y-~~axis (many~~ feet versus ~~a lot of nautical miles~~) ~~cause the~~ non-~~linear spacing between the elevation angle marks~~. ~~The height is shown as a linear grid pattern~~. ~~A second~~ (~~dotted~~) ~~grid is orientated on the curvature of the earth~~.		radiant lines adalah tanda sudut elevasi, di sini dalam half-degree-steps. Skala sumbu x dan sumbu y yang tidak sama (banyak-nya feet versus banyak-nya mil laut) menyebabkan jarak non-linier antara tanda sudut elevasi. Ketinggian ditampilkan sebagai pola kisi linier. Kisi kedua (bertitik) berorientasi pada kelengkungan bumi.

	==3D Antenna Patterns==		==3D Antenna Patterns==

Unknown user: /* Pola Radiasi Horizontal */

2022-11-16T06:31:48Z

Pola Radiasi Horizontal

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	Diagram antena horizontal adalah tampilan bidang medan elektromagnetik antena, direpresentasikan sebagai bidang dua dimensi dengan antena di tengah.		Diagram antena horizontal adalah tampilan bidang medan elektromagnetik antena, direpresentasikan sebagai bidang dua dimensi dengan antena di tengah.

			Kepentingan representasi ini terletak pada akuisisi sederhana dari directivity antena. Biasanya, nilai -3 dB juga diberikan pada skala sebagai lingkaran putus-putus. Titik persilangan antara main lobe dan lingkaran ini menghasilkan apa yang disebut half power beam width antena. Parameter lain yang mudah dibaca adalah forward/backward ratio, yaitu rasio antara main lobe dan back lobe, serta ukuran dan arah sidelobe.

	The interest in this representation lies in the simple acquisition of the directivity of the antenna. Usually, the value -3 dB is also given on the scale as a dotted circle. The crossing points between the main lobe and this circle result in the so-called half power beam width of the antenna. Other easily readable parameters are the forward/backward ratio, i.e. the ratio between the main lobe and the back lobes, as well as the size and direction of the sidelobes.		Dengan antena radar, rasio antara main dan sidelobe adalah penting. Parameter ini secara langsung mempengaruhi evaluasi ketahanan radar terhadap interferensi.

	~~With~~ radar ~~antennas~~, ~~the ratio between~~ main ~~and sidelobes is important~~. ~~This parameter directly influences the evaluation of the immunity of~~ radar ~~to interference~~.

	==Vertical Radiation Pattern==		==Vertical Radiation Pattern==

Unknown user: /* Presentasi Format */

2022-11-16T06:28:06Z

Presentasi Format

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	==Presentasi Format==		==Presentasi Format==

	Banyak format tampilan yang digunakan. Sistem koordinat ~~Cartesian~~, serta sistem koordinat polar, adalah umum. Tujuan utamanya adalah untuk menampilkan diagram radiasi yang representatif baik secara horizontal (dalam azimuth) untuk representasi 360° yang lengkap atau secara vertikal (dalam elevasi) sebagian besar hanya untuk 90 atau 180 derajat. Dalam sistem koordinat Cartesian, data antena dapat direpresentasikan dengan lebih baik. Karena data ini juga dapat dicetak sebagai tabel, representasi yang lebih deskriptif sebagai kurva lokus dalam sistem koordinat polar biasanya lebih disukai. Berbeda dengan sistem koordinat Cartesian, ini menunjukkan arah secara langsung.		Banyak format tampilan yang digunakan. Sistem koordinat Kartesian, serta sistem koordinat polar, adalah umum. Tujuan utamanya adalah untuk menampilkan diagram radiasi yang representatif baik secara horizontal (dalam azimuth) untuk representasi 360° yang lengkap atau secara vertikal (dalam elevasi) sebagian besar hanya untuk 90 atau 180 derajat. Dalam sistem koordinat Cartesian, data antena dapat direpresentasikan dengan lebih baik. Karena data ini juga dapat dicetak sebagai tabel, representasi yang lebih deskriptif sebagai kurva lokus dalam sistem koordinat polar biasanya lebih disukai. Berbeda dengan sistem koordinat Cartesian, ini menunjukkan arah secara langsung.

	Untuk penanganan yang mudah, transparansi, dan keserbagunaan maksimum, pola radiasi biasanya dinormalisasi ke tepi luar sistem koordinat. Ini berarti bahwa nilai maksimum yang diukur disejajarkan dengan 0° dan diplot di tepi atas diagram. Nilai terukur lebih lanjut dari diagram radiasi biasanya ditampilkan relatif terhadap nilai maksimum ini dalam dB (desibel).		Untuk penanganan yang mudah, transparansi, dan keserbagunaan maksimum, pola radiasi biasanya dinormalisasi ke tepi luar sistem koordinat. Ini berarti bahwa nilai maksimum yang diukur disejajarkan dengan 0° dan diplot di tepi atas diagram. Nilai terukur lebih lanjut dari diagram radiasi biasanya ditampilkan relatif terhadap nilai maksimum ini dalam dB (desibel).

Unknown user at 06:27, 16 November 2022

2022-11-16T06:27:04Z

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	[[File:Horizontal2.png\|center\|300px\|thumb\|Gambar: Penampang horizontal dari pola radiasi dalam sistem koordinat polar]]		[[File:Horizontal2.png\|center\|300px\|thumb\|Gambar: Penampang horizontal dari pola radiasi dalam sistem koordinat polar]]

	==~~Presentation~~ Format==		==Presentasi Format==

	Banyak format tampilan yang digunakan. Sistem koordinat Cartesian, serta sistem koordinat polar, adalah umum. Tujuan utamanya adalah untuk menampilkan diagram radiasi yang representatif baik secara horizontal (dalam azimuth) untuk representasi 360° yang lengkap atau secara vertikal (dalam elevasi) sebagian besar hanya untuk 90 atau 180 derajat. Dalam sistem koordinat Cartesian, data antena dapat direpresentasikan dengan lebih baik. Karena data ini juga dapat dicetak sebagai tabel, representasi yang lebih deskriptif sebagai kurva lokus dalam sistem koordinat polar biasanya lebih disukai. Berbeda dengan sistem koordinat Cartesian, ini menunjukkan arah secara langsung.		Banyak format tampilan yang digunakan. Sistem koordinat Cartesian, serta sistem koordinat polar, adalah umum. Tujuan utamanya adalah untuk menampilkan diagram radiasi yang representatif baik secara horizontal (dalam azimuth) untuk representasi 360° yang lengkap atau secara vertikal (dalam elevasi) sebagian besar hanya untuk 90 atau 180 derajat. Dalam sistem koordinat Cartesian, data antena dapat direpresentasikan dengan lebih baik. Karena data ini juga dapat dicetak sebagai tabel, representasi yang lebih deskriptif sebagai kurva lokus dalam sistem koordinat polar biasanya lebih disukai. Berbeda dengan sistem koordinat Cartesian, ini menunjukkan arah secara langsung.
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	Untuk penanganan yang mudah, transparansi, dan keserbagunaan maksimum, pola radiasi biasanya dinormalisasi ke tepi luar sistem koordinat. Ini berarti bahwa nilai maksimum yang diukur disejajarkan dengan 0° dan diplot di tepi atas diagram. Nilai terukur lebih lanjut dari diagram radiasi biasanya ditampilkan relatif terhadap nilai maksimum ini dalam dB (desibel).		Untuk penanganan yang mudah, transparansi, dan keserbagunaan maksimum, pola radiasi biasanya dinormalisasi ke tepi luar sistem koordinat. Ini berarti bahwa nilai maksimum yang diukur disejajarkan dengan 0° dan diplot di tepi atas diagram. Nilai terukur lebih lanjut dari diagram radiasi biasanya ditampilkan relatif terhadap nilai maksimum ini dalam dB (desibel).

	==~~Usual Scales~~==		==Skala yang biasa digunakan==

	~~The scale in the~~ diagram ~~can be varied~~. ~~Three types of~~ plotting ~~scales are in common usage; linear~~, ~~linear logarithmic and modified logarithmic~~. ~~The linear scale emphasizes the main radiation beam and usually suppresses all sidelobes~~, ~~as they are often in the order of less than one-hundredth of the~~ main ~~lobes~~. ~~However~~, ~~the linear logarithmic scale represents the sidelobes well and is preferred when the~~ level ~~of all sidelobes is important~~. ~~However~~, ~~it leaves the impression that the antenna is bad because the~~ main lobe ~~is relatively small~~. ~~The modified logarithmic scale (figure 4) emphasizes the shape of the~~ major beam ~~while compressing very low-level~~ (<30 dB) ~~sidelobes towards the~~ center ~~of the~~ pattern. ~~The main~~ lobe ~~is thus twice as large as the strongest~~ side lobe, ~~which is advantageous for~~ visual ~~presentations~~. ~~However~~, ~~this form of presentation is rarely used in technology because exact~~ data ~~would be difficult to read from it~~.		Skala dalam diagram dapat bervariasi. Tiga jenis skala plotting digunakan secara umum, yaitu,
			* linier,
			* logaritma linier,
			* logaritma termodifikasi.
			Skala linier menekankan pancaran radiasi utama dan biasanya menekan semua sidelobe, karena seringkali berada di urutan kurang dari seperseratus main lobe. Namun, skala logaritmik linier mewakili sidelobe dengan baik dan lebih disukai ketika level semua sidelobe penting. Namun, kesan antena buruk karena main lobe relatif kecil. Skala logaritmik yang dimodifikasi, seperti tampak pada gambar, menekankan bentuk major beam sambil mengompresi sidelobe tingkat sangat rendah (<30 dB) menuju center dari pattern. Main lobe dengan demikian dua kali lebih besar dari side lobe terkuat, yang menguntungkan untuk presentasi visual. Namun, bentuk presentasi ini jarang digunakan dalam teknologi karena data yang tepat akan sulit dibaca darinya.

	==Horizontal ~~Radiation Pattern~~==		==Pola Radiasi Horizontal==

			Diagram antena horizontal adalah tampilan bidang medan elektromagnetik antena, direpresentasikan sebagai bidang dua dimensi dengan antena di tengah.

	~~A horizontal antenna diagram is a plan view of the electromagnetic field of an antenna, represented as a two-dimensional plane with the antenna in the center.~~

	The interest in this representation lies in the simple acquisition of the directivity of the antenna. Usually, the value -3 dB is also given on the scale as a dotted circle. The crossing points between the main lobe and this circle result in the so-called half power beam width of the antenna. Other easily readable parameters are the forward/backward ratio, i.e. the ratio between the main lobe and the back lobes, as well as the size and direction of the sidelobes.		The interest in this representation lies in the simple acquisition of the directivity of the antenna. Usually, the value -3 dB is also given on the scale as a dotted circle. The crossing points between the main lobe and this circle result in the so-called half power beam width of the antenna. Other easily readable parameters are the forward/backward ratio, i.e. the ratio between the main lobe and the back lobes, as well as the size and direction of the sidelobes.

Unknown user at 06:17, 16 November 2022

2022-11-16T06:17:32Z

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	==Presentation Format==		==Presentation Format==

	~~Many display formats are used~~. Cartesian ~~coordinate systems~~, ~~as well as~~ polar ~~coordinate systems~~, ~~are common~~. ~~The main goal is to display a radiation~~ diagram ~~that is representative either horizontally~~ (in azimuth) ~~for a complete~~ 360° ~~representation or vertically~~ (~~in elevation~~) ~~mostly only for~~ 90 or 180 ~~degrees~~. ~~In the~~ Cartesian ~~coordinate system~~, ~~the~~ data ~~of an antenna can be represented better~~. ~~Since these~~ data ~~can also be printed out as a table~~, ~~the more descriptive representation as a locus curve in a~~ polar ~~coordinate system is usually preferred~~. ~~In contrast to the~~ Cartesian ~~coordinate system~~, ~~this indicates the direction directly~~.		Banyak format tampilan yang digunakan. Sistem koordinat Cartesian, serta sistem koordinat polar, adalah umum. Tujuan utamanya adalah untuk menampilkan diagram radiasi yang representatif baik secara horizontal (dalam azimuth) untuk representasi 360° yang lengkap atau secara vertikal (dalam elevasi) sebagian besar hanya untuk 90 atau 180 derajat. Dalam sistem koordinat Cartesian, data antena dapat direpresentasikan dengan lebih baik. Karena data ini juga dapat dicetak sebagai tabel, representasi yang lebih deskriptif sebagai kurva lokus dalam sistem koordinat polar biasanya lebih disukai. Berbeda dengan sistem koordinat Cartesian, ini menunjukkan arah secara langsung.

	~~For easy handling~~, ~~transparency and maximum versatility~~, ~~radiation patterns are usually normalized to the outer edge of the coordinate system~~. ~~This means that the measured maximum value is aligned to~~ 0° ~~and plotted on the upper edge of the~~ diagram. ~~Further measured values of the radiation~~ diagram ~~are usually displayed relative to this maximum value in~~ dB (~~decibels~~).		Untuk penanganan yang mudah, transparansi, dan keserbagunaan maksimum, pola radiasi biasanya dinormalisasi ke tepi luar sistem koordinat. Ini berarti bahwa nilai maksimum yang diukur disejajarkan dengan 0° dan diplot di tepi atas diagram. Nilai terukur lebih lanjut dari diagram radiasi biasanya ditampilkan relatif terhadap nilai maksimum ini dalam dB (desibel).

	==Usual Scales==		==Usual Scales==

Unknown user at 06:14, 16 November 2022

2022-11-16T06:14:44Z

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	~~The radiation pattern or antenna pattern is the graphical representation of the~~		Pola radiasi atau pola antena adalah representasi grafis dari sifat radiasi antena sebagai fungsi ruang. Artinya, pola antena menggambarkan bagaimana antena memancarkan energi elektromagnetik ke udara (atau bagaimana antena menerima energi). Penting untuk menyatakan bahwa antena memancarkan energi ke segala arah, setidaknya sampai batas tertentu, sehingga pola antena sebenarnya adalah tiga dimensi. Namun, umum untuk menggambarkan pola 3D ini dengan dua pola planar, yang disebut pola bidang utama. Pola bidang utama ini dapat diperoleh dengan membuat dua irisan melalui pola 3D melalui nilai maksimum pola atau dengan pengukuran langsung. Pola bidang utama inilah yang biasanya disebut sebagai pola antena.
	~~radiation properties of the antenna as a function of space~~. ~~That is~~, ~~the antenna’s pattern describes how the antenna radiates energy out into space~~ (~~or how it receives energy~~). ~~It is important to state that an antenna radiates energy in all directions~~, ~~at least to some extent~~, ~~so the antenna pattern is actually three-dimensional~~. ~~It is common~~, ~~however, to describe this~~ 3D ~~pattern with two~~ planar ~~patterns~~, ~~called the principal plane patterns~~. ~~These principal plane patterns can be obtained by making two slices through the~~ 3D ~~pattern through the maximum value of the pattern or by direct measurement~~. ~~It is these principal plane patterns that are commonly referred to as the antenna patterns~~.

			Pola radiasi antena adalah salah satu sifat dasarnya karena menunjukkan cara antena mendistribusikan energinya di udara. Ini umumnya terdiri dari sejumlah lobe (gelembung) dan jika diukur jauh dari antena itu tidak bergantung pada jarak. Ini adalah fungsi dari sudut dan dapat dinyatakan sebagai pola medan atau kekuatan. Biasanya dapat sepenuhnya ditentukan dari pola dalam dua bidang, tegak lurus satu sama lain, masing-masing bidang E dan H. Terkait dengan pola radiasi antena, terdapat beberapa parameter penting seperti daya pancar, efisiensi radiasi, directivity, gain, dan polarisasi antena.

			Pola radiasi antena adalah representasi grafis dari elemen karakteristik radiasi antena. Pola antena biasanya merupakan representasi grafis dari karakteristik arah antena. Ini mewakili intensitas relatif dari radiasi energi atau jumlah kekuatan medan listrik atau magnet sebagai fungsi dari arah ke antena. Diagram antena diukur atau dihasilkan oleh program simulasi di komputer, misalnya, untuk menampilkan secara grafis keterarahan antena radar dan dengan demikian memperkirakan kinerjanya.
	~~The radiation pattern of an antenna is one of its basic properties since it shows the way the antenna distributes its energy in space~~. ~~It generally consists of a number of lobes and if it is measured far away from the antenna it is independent of distance~~. ~~It is a function of angles and can be expressed as field or power pattern~~. ~~It usually can be completely specified from the patterns in two planes~~, ~~perpendicular to each other~~, the E and H planes, respectively. Related to the radiation pattern of an antenna, a number of important parameters exist, such as radiated power, radiation efficiency, directivity, gain, and antenna polarization.


	Antenna radiation patterns are graphical representations of elements of the radiation characteristics of an antenna. The antenna pattern is usually a graphical representation of the antenna's directional characteristic. It represents the relative intensity of the energy radiation or the amount of the electric or magnetic field strength as a function of the direction to the antenna. Antenna diagrams are measured or generated by simulation programs on the computer, for example, to graphically display the directivity of a radar ~~antenna and thus estimate its performance~~.

	[[File:Horizontal1.png\|center\|300px\|thumb]]		[[File:Horizontal1.png\|center\|300px\|thumb]]

	~~In contrast to an~~ omni-directional ~~antenna~~, ~~which radiates uniformly in all directions of a plane~~, a directional ~~antenna prefers one direction and therefore achieves a longer range in this one direction with lower transmission power~~. ~~The antenna radiation pattern graphically illustrates the preference determined by measurement~~. ~~Due to the reciprocity~~, ~~which guarantees the same transmission and reception characteristics of the antenna~~, ~~the~~ diagram ~~shows both the directionally distributed transmission power as field strength and the sensitivity of an antenna during the reception~~.		Berbeda dengan antena omni-directional, yang memancar secara seragam ke segala arah bidang, antena directional lebih memilih satu arah dan karena itu mencapai jangkauan yang lebih jauh dalam satu arah ini dengan daya transmisi yang lebih rendah. Pola radiasi antena secara grafis menggambarkan preferensi yang ditentukan oleh pengukuran. Karena resiprositas, yang menjamin karakteristik transmisi dan penerimaan antena yang sama, diagram menunjukkan daya transmisi yang didistribusikan secara terarah sebagai kekuatan medan dan sensitivitas antena selama penerimaan.

	[[File:Horizontal2.png\|center\|300px\|thumb]]		[[File:Horizontal2.png\|center\|300px\|thumb\|Gambar: Penampang horizontal dari pola radiasi dalam sistem koordinat polar]]

	~~Figure 2: Horizontal cross-section of the radiation pattern in a polar coordinate system~~		==Presentation Format==

	~~Presentation Formats~~
	Many display formats are used. Cartesian coordinate systems, as well as polar coordinate systems, are common. The main goal is to display a radiation diagram that is representative either horizontally (in azimuth) for a complete 360° representation or vertically (in elevation) mostly only for 90 or 180 degrees. In the Cartesian coordinate system, the data of an antenna can be represented better. Since these data can also be printed out as a table, the more descriptive representation as a locus curve in a polar coordinate system is usually preferred. In contrast to the Cartesian coordinate system, this indicates the direction directly.		Many display formats are used. Cartesian coordinate systems, as well as polar coordinate systems, are common. The main goal is to display a radiation diagram that is representative either horizontally (in azimuth) for a complete 360° representation or vertically (in elevation) mostly only for 90 or 180 degrees. In the Cartesian coordinate system, the data of an antenna can be represented better. Since these data can also be printed out as a table, the more descriptive representation as a locus curve in a polar coordinate system is usually preferred. In contrast to the Cartesian coordinate system, this indicates the direction directly.

	For easy handling, transparency and maximum versatility, radiation patterns are usually normalized to the outer edge of the coordinate system. This means that the measured maximum value is aligned to 0° and plotted on the upper edge of the diagram. Further measured values of the radiation diagram are usually displayed relative to this maximum value in dB (decibels).		For easy handling, transparency and maximum versatility, radiation patterns are usually normalized to the outer edge of the coordinate system. This means that the measured maximum value is aligned to 0° and plotted on the upper edge of the diagram. Further measured values of the radiation diagram are usually displayed relative to this maximum value in dB (decibels).

	Usual Scales		==Usual Scales==

	The scale in the diagram can be varied. Three types of plotting scales are in common usage; linear, linear logarithmic and modified logarithmic. The linear scale emphasizes the main radiation beam and usually suppresses all sidelobes, as they are often in the order of less than one-hundredth of the main lobes. However, the linear logarithmic scale represents the sidelobes well and is preferred when the level of all sidelobes is important. However, it leaves the impression that the antenna is bad because the main lobe is relatively small. The modified logarithmic scale (figure 4) emphasizes the shape of the major beam while compressing very low-level (<30 dB) sidelobes towards the center of the pattern. The main lobe is thus twice as large as the strongest side lobe, which is advantageous for visual presentations. However, this form of presentation is rarely used in technology because exact data would be difficult to read from it.		The scale in the diagram can be varied. Three types of plotting scales are in common usage; linear, linear logarithmic and modified logarithmic. The linear scale emphasizes the main radiation beam and usually suppresses all sidelobes, as they are often in the order of less than one-hundredth of the main lobes. However, the linear logarithmic scale represents the sidelobes well and is preferred when the level of all sidelobes is important. However, it leaves the impression that the antenna is bad because the main lobe is relatively small. The modified logarithmic scale (figure 4) emphasizes the shape of the major beam while compressing very low-level (<30 dB) sidelobes towards the center of the pattern. The main lobe is thus twice as large as the strongest side lobe, which is advantageous for visual presentations. However, this form of presentation is rarely used in technology because exact data would be difficult to read from it.

	Horizontal Radiation Pattern		==Horizontal Radiation Pattern==

	A horizontal antenna diagram is a plan view of the electromagnetic field of an antenna, represented as a two-dimensional plane with the antenna in the center.		A horizontal antenna diagram is a plan view of the electromagnetic field of an antenna, represented as a two-dimensional plane with the antenna in the center.

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	With radar antennas, the ratio between main and sidelobes is important. This parameter directly influences the evaluation of the immunity of radar to interference.		With radar antennas, the ratio between main and sidelobes is important. This parameter directly influences the evaluation of the immunity of radar to interference.

	Vertical Radiation Pattern		==Vertical Radiation Pattern==

	The shape of the vertical pattern is a vertical cross cut of the three-dimensional graph. In the shown polar diagram (a quarter part of the circle) with the antenna site as the origin, the x-axis is the radar range, and the y-axis the aims height. One of the antenna measurement techniques is the Sun-Strobe-Recording using RASS-S, a measurement tool of Intersoft Electronics. The RASS-S (Radar Analysis Support System for Sites) is a radar manufacturer-independent system for evaluating the different elements of radar by connecting to signals which are already available and this under operational conditions.		The shape of the vertical pattern is a vertical cross cut of the three-dimensional graph. In the shown polar diagram (a quarter part of the circle) with the antenna site as the origin, the x-axis is the radar range, and the y-axis the aims height. One of the antenna measurement techniques is the Sun-Strobe-Recording using RASS-S, a measurement tool of Intersoft Electronics. The RASS-S (Radar Analysis Support System for Sites) is a radar manufacturer-independent system for evaluating the different elements of radar by connecting to signals which are already available and this under operational conditions.

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	The radiant lines are marks of elevation angles, here in half-degree-steps. The unequal scales of the x-axis and the y-axis (many feet versus a lot of nautical miles) cause the non-linear spacing between the elevation angle marks. The height is shown as a linear grid pattern. A second (dotted) grid is orientated on the curvature of the earth.		The radiant lines are marks of elevation angles, here in half-degree-steps. The unequal scales of the x-axis and the y-axis (many feet versus a lot of nautical miles) cause the non-linear spacing between the elevation angle marks. The height is shown as a linear grid pattern. A second (dotted) grid is orientated on the curvature of the earth.

			==3D Antenna Patterns==

	[[File:Feedhorn.png\|center\|300px\|thumb]]		[[File:Feedhorn.png\|center\|300px\|thumb]]
	~~3D Antenna Patterns~~
	Three-dimensional antenna pattern of a feedhorn,		Three-dimensional antenna pattern of a feedhorn,
	~~(click to enlarge: 800·600px = 49 kByte)~~
	Figure 4: Three-dimensional antenna pattern of a feed horn		Figure 4: Three-dimensional antenna pattern of a feed horn

Unknown user at 07:11, 2 November 2022

2022-11-02T07:11:48Z

← Older revision		Revision as of 07:11, 2 November 2022
Line 8:		Line 8:

	Antenna radiation patterns are graphical representations of elements of the radiation characteristics of an antenna. The antenna pattern is usually a graphical representation of the antenna's directional characteristic. It represents the relative intensity of the energy radiation or the amount of the electric or magnetic field strength as a function of the direction to the antenna. Antenna diagrams are measured or generated by simulation programs on the computer, for example, to graphically display the directivity of a radar antenna and thus estimate its performance.		Antenna radiation patterns are graphical representations of elements of the radiation characteristics of an antenna. The antenna pattern is usually a graphical representation of the antenna's directional characteristic. It represents the relative intensity of the energy radiation or the amount of the electric or magnetic field strength as a function of the direction to the antenna. Antenna diagrams are measured or generated by simulation programs on the computer, for example, to graphically display the directivity of a radar antenna and thus estimate its performance.

			[[File:Horizontal1.png\|center\|300px\|thumb]]

	In contrast to an omni-directional antenna, which radiates uniformly in all directions of a plane, a directional antenna prefers one direction and therefore achieves a longer range in this one direction with lower transmission power. The antenna radiation pattern graphically illustrates the preference determined by measurement. Due to the reciprocity, which guarantees the same transmission and reception characteristics of the antenna, the diagram shows both the directionally distributed transmission power as field strength and the sensitivity of an antenna during the reception.		In contrast to an omni-directional antenna, which radiates uniformly in all directions of a plane, a directional antenna prefers one direction and therefore achieves a longer range in this one direction with lower transmission power. The antenna radiation pattern graphically illustrates the preference determined by measurement. Due to the reciprocity, which guarantees the same transmission and reception characteristics of the antenna, the diagram shows both the directionally distributed transmission power as field strength and the sensitivity of an antenna during the reception.

			[[File:Horizontal2.png\|center\|300px\|thumb]]

	~~back lobes~~
	~~sidelobes~~
	~~main lobe~~
	Figure 2: Horizontal cross-section of the radiation pattern in a polar coordinate system		Figure 2: Horizontal cross-section of the radiation pattern in a polar coordinate system

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	The shape of the vertical pattern is a vertical cross cut of the three-dimensional graph. In the shown polar diagram (a quarter part of the circle) with the antenna site as the origin, the x-axis is the radar range, and the y-axis the aims height. One of the antenna measurement techniques is the Sun-Strobe-Recording using RASS-S, a measurement tool of Intersoft Electronics. The RASS-S (Radar Analysis Support System for Sites) is a radar manufacturer-independent system for evaluating the different elements of radar by connecting to signals which are already available and this under operational conditions.		The shape of the vertical pattern is a vertical cross cut of the three-dimensional graph. In the shown polar diagram (a quarter part of the circle) with the antenna site as the origin, the x-axis is the radar range, and the y-axis the aims height. One of the antenna measurement techniques is the Sun-Strobe-Recording using RASS-S, a measurement tool of Intersoft Electronics. The RASS-S (Radar Analysis Support System for Sites) is a radar manufacturer-independent system for evaluating the different elements of radar by connecting to signals which are already available and this under operational conditions.

			[[File:Vertical.png\|center\|300px\|thumb]]
	Figure 3: Vertical antenna pattern with cosecant squared characteristic		Figure 3: Vertical antenna pattern with cosecant squared characteristic

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	The radiant lines are marks of elevation angles, here in half-degree-steps. The unequal scales of the x-axis and the y-axis (many feet versus a lot of nautical miles) cause the non-linear spacing between the elevation angle marks. The height is shown as a linear grid pattern. A second (dotted) grid is orientated on the curvature of the earth.		The radiant lines are marks of elevation angles, here in half-degree-steps. The unequal scales of the x-axis and the y-axis (many feet versus a lot of nautical miles) cause the non-linear spacing between the elevation angle marks. The height is shown as a linear grid pattern. A second (dotted) grid is orientated on the curvature of the earth.

			[[File:Feedhorn.png\|center\|300px\|thumb]]
	3D Antenna Patterns		3D Antenna Patterns
	Three-dimensional antenna pattern of a feedhorn,		Three-dimensional antenna pattern of a feedhorn,

Unknown user at 07:02, 2 November 2022

2022-11-02T07:02:47Z

← Older revision		Revision as of 07:02, 2 November 2022
Line 5:		Line 5:

	The radiation pattern of an antenna is one of its basic properties since it shows the way the antenna distributes its energy in space. It generally consists of a number of lobes and if it is measured far away from the antenna it is independent of distance. It is a function of angles and can be expressed as field or power pattern. It usually can be completely specified from the patterns in two planes, perpendicular to each other, the E and H planes, respectively. Related to the radiation pattern of an antenna, a number of important parameters exist, such as radiated power, radiation efficiency, directivity, gain, and antenna polarization.		The radiation pattern of an antenna is one of its basic properties since it shows the way the antenna distributes its energy in space. It generally consists of a number of lobes and if it is measured far away from the antenna it is independent of distance. It is a function of angles and can be expressed as field or power pattern. It usually can be completely specified from the patterns in two planes, perpendicular to each other, the E and H planes, respectively. Related to the radiation pattern of an antenna, a number of important parameters exist, such as radiated power, radiation efficiency, directivity, gain, and antenna polarization.


			Antenna radiation patterns are graphical representations of elements of the radiation characteristics of an antenna. The antenna pattern is usually a graphical representation of the antenna's directional characteristic. It represents the relative intensity of the energy radiation or the amount of the electric or magnetic field strength as a function of the direction to the antenna. Antenna diagrams are measured or generated by simulation programs on the computer, for example, to graphically display the directivity of a radar antenna and thus estimate its performance.

			In contrast to an omni-directional antenna, which radiates uniformly in all directions of a plane, a directional antenna prefers one direction and therefore achieves a longer range in this one direction with lower transmission power. The antenna radiation pattern graphically illustrates the preference determined by measurement. Due to the reciprocity, which guarantees the same transmission and reception characteristics of the antenna, the diagram shows both the directionally distributed transmission power as field strength and the sensitivity of an antenna during the reception.


			back lobes
			sidelobes
			main lobe
			Figure 2: Horizontal cross-section of the radiation pattern in a polar coordinate system

			Presentation Formats
			Many display formats are used. Cartesian coordinate systems, as well as polar coordinate systems, are common. The main goal is to display a radiation diagram that is representative either horizontally (in azimuth) for a complete 360° representation or vertically (in elevation) mostly only for 90 or 180 degrees. In the Cartesian coordinate system, the data of an antenna can be represented better. Since these data can also be printed out as a table, the more descriptive representation as a locus curve in a polar coordinate system is usually preferred. In contrast to the Cartesian coordinate system, this indicates the direction directly.

			For easy handling, transparency and maximum versatility, radiation patterns are usually normalized to the outer edge of the coordinate system. This means that the measured maximum value is aligned to 0° and plotted on the upper edge of the diagram. Further measured values of the radiation diagram are usually displayed relative to this maximum value in dB (decibels).

			Usual Scales
			The scale in the diagram can be varied. Three types of plotting scales are in common usage; linear, linear logarithmic and modified logarithmic. The linear scale emphasizes the main radiation beam and usually suppresses all sidelobes, as they are often in the order of less than one-hundredth of the main lobes. However, the linear logarithmic scale represents the sidelobes well and is preferred when the level of all sidelobes is important. However, it leaves the impression that the antenna is bad because the main lobe is relatively small. The modified logarithmic scale (figure 4) emphasizes the shape of the major beam while compressing very low-level (<30 dB) sidelobes towards the center of the pattern. The main lobe is thus twice as large as the strongest side lobe, which is advantageous for visual presentations. However, this form of presentation is rarely used in technology because exact data would be difficult to read from it.

			Horizontal Radiation Pattern
			A horizontal antenna diagram is a plan view of the electromagnetic field of an antenna, represented as a two-dimensional plane with the antenna in the center.

			The interest in this representation lies in the simple acquisition of the directivity of the antenna. Usually, the value -3 dB is also given on the scale as a dotted circle. The crossing points between the main lobe and this circle result in the so-called half power beam width of the antenna. Other easily readable parameters are the forward/backward ratio, i.e. the ratio between the main lobe and the back lobes, as well as the size and direction of the sidelobes.

			With radar antennas, the ratio between main and sidelobes is important. This parameter directly influences the evaluation of the immunity of radar to interference.

			Vertical Radiation Pattern
			The shape of the vertical pattern is a vertical cross cut of the three-dimensional graph. In the shown polar diagram (a quarter part of the circle) with the antenna site as the origin, the x-axis is the radar range, and the y-axis the aims height. One of the antenna measurement techniques is the Sun-Strobe-Recording using RASS-S, a measurement tool of Intersoft Electronics. The RASS-S (Radar Analysis Support System for Sites) is a radar manufacturer-independent system for evaluating the different elements of radar by connecting to signals which are already available and this under operational conditions.


			Figure 3: Vertical antenna pattern with cosecant squared characteristic

			In the shown Figure 3, the measurement units are nautical miles as range, and feet as height. Both measurement units are still used in Air- Traffic- Management by historical reasons. These units are of secondarily meaning only because the plotted quantity of radiation pattern is defined as a relative level. This means the boresight axis has got the value of the (theoretical) maximum range calculated with the help of the Radar Equation. The shape of the plot provides the required information only! To get absolute values you need a second plot, measured under the same conditions. These two plots you can compare and then you achieve over increasing or decreasing the antennas performance.

			The radiant lines are marks of elevation angles, here in half-degree-steps. The unequal scales of the x-axis and the y-axis (many feet versus a lot of nautical miles) cause the non-linear spacing between the elevation angle marks. The height is shown as a linear grid pattern. A second (dotted) grid is orientated on the curvature of the earth.

			3D Antenna Patterns
			Three-dimensional antenna pattern of a feedhorn,
			(click to enlarge: 800·600px = 49 kByte)
			Figure 4: Three-dimensional antenna pattern of a feed horn

			Antenna diagrams in three-dimensional representation are mostly computer-generated images. Mostly they are generated by simulation programs whose values are astonishingly close to a real measured diagram. To generate a real measured diagram means an immense measuring effort since each pixel of the image represents its own measured value.

			Most antenna measurement programs, therefore, choose a compromise for this representation. Only a vertical and a horizontal section through the antenna diagram are available as real measured values. All other pixels are calculated by multiplying the entire measurement curve of the vertical diagram by a single measurement value of the horizontal diagram. The computing power required is enormous. With the exception of a pleasing representation in presentations, the benefit is doubtful, since no new information can be gained from this representation compared to the two individual diagrams (horizontal and vertical antenna diagram). On the contrary: especially in the peripheral zones, a diagram generated with this compromise should deviate considerably from the reality.

			Also, 3D diagrams can be represented in Cartesian as well as in polar coordinates.






			==Referensi==

			* https://www.radartutorial.eu/06.antennas/Antenna%20Pattern.en.html