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"Antenna can be one of the largest components in a wireless device; therefore antenna miniaturization can reduce the overall size of wireless devices. One method used to reduce the element size of an antenna is by using metamaterial structures. This paper discusses a Left-Handed Metamaterial (LHM) structure stacked on a two-element microstrip antennas array for miniaturization and gain enhancement at a frequency of 2.35 GHz. To observe the impact of the LHM structure on the antenna, first this paper discuss the design of a conventional rectangular shape microstrip antenna without a LHM structure, then a design of the LHM structure which shows both negative permittivity and negative permeability. This LHM structure is then implemented on a conventional single element microstrip antenna and on a two-element microstrip antennas array. Results and discussion of implementation of the LHM structure on the conventional microstrip antenna is provided in this paper.

The results show that good agreement between simulated and measured results has been achieved. The simulation results show that the antenna works at a frequency of 2.29?2.42 GHz with a bandwidth of 128 MHz (5.4%) and a gain of 8.2 dBi, while the measurements show that the antenna works at a frequency of 2.26?2.41 GHz with a bandwidth of 146 MHz (6.21%) and a gain of 8.97 dBi. In addition, by comparing the substrate dimension for the two element array antennas, with and without the LHM structure, shows a 39% reduction is achieved."

"Antenna can be one of the largest components in a wireless device; therefore antenna miniaturization can reduce the overall size of wireless devices. One method used to reduce the element size of an antenna is by using meta material structures. This paper discusses a Left-Handed Meta material (LHM) structure stacked on a two-element microstrip antennas array for miniaturization and gain enhancement at a frequency of 2.35 GHz. To observe the impact of the LHM structure on the antenna, first this paper discuss the design of a conventional rectangular shape microstrip antenna without a LHM structure, then a design of the LHM structure which shows both negative permittivity and negative permeability. This LHM structure is then implemented on a conventional single element microstrip antenna and on a two-element microstrip antennas array. Results and discussion of implementation of the LHM structure on the conventional microstrip antenna is provided in this paper. The results show that good agreement between simulated and measured results has been achieved. The simulation results show that the antenna works at a frequency of 2.29–2.42 GHz with a bandwidth of 128 MHz (5.4%) and a gain of 8.2 dBi, while the measurements show that the antenna works at a frequency of 2.26–2.41 GHz with a bandwidth of 146 MHz (6.21%) and a gain of 8.97 dBi. In addition, by comparing the substrate dimension for the two element array antennas, with and without the LHM structure, shows a 39% reduction is achieved."

"Desain Left-Handed Metamaterial (LHM) yang dirancang untuk frekuensi 2,8-3,1 GHz dengan bandwidth 300 MHz untuk aplikasi radar. Struktur LHM ditempatkan dibagian atas antena mikrostrip dengan diberi jarak atau gap sehingga dapat menekan side lobe level. Hasil simulasi menunjukkan bahwa side lobe level antena single elemen dengan penambahan struktur LHM mengalami penekanan side lobe level dari -9,23 dB menjadi -21,11 dB pada phi=0. Dan side lobe level antena array 4 elemen dengan penambahan struktur LHM mengalami penekanan dari -8,93 dB menjadi -15,86 dB pada phi = 0. Hasil pengukuran untuk antena single elemen dengan penambahan struktur LHM menunjukkan bahwa antena bekerja pada frekuensi 2,74 – 3,07 GHz dengan bandwidth 330 MHz, return loss -14 dB dan side lobe level -16,7 dB pada phi = 0. Sedangkan untuk antena array 4 elemen dengan penambahan struktur LHM menunjukkan bahwa antena bekerja pada frekuensi 2,74 – 3,06 GHz dengan bandwidth 320 MHz, return loss -14 dB, dan side lobe level -10,75 dB pada phi = 0.

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Design of the Left-Handed Metamaterial (LHM) structure which operates at the frequency 2.8-3.1 GHz with a bandwidth of 300MHz for radar applications. LHM structure is placed at the top of the microstrip antenna with a given distance or gap so the LHM structure can suppress the side lobe levels. The results of the simulation shows that the side lobe level of a single antenna element with LHM structure can suppress side lobe level from -9.23 dB to -21.11 dB at phi = 0. In addition, the side lobe level of antenna array 4 elements with LHM structure is suppressed from -8.93 dB to -15,86 dB at phi = 0. The measurement results for single antenna element with LHM structure shows that the antenna works at a frequency of 2.74 – 3.07 GHz with a bandwidth of 330 MHz, -14 dB return loss and the side lobe level of -16.7 dB at phi = 0. In addition, antenna array 4 element with LHM structure shows that the antenna works at a frequency of 2.74 – 3.06 GHz with a bandwidth of 320 MHz, -14 dB return loss, and the side lobe level of -10.75 dB at phi = 0.

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"Saat ini, antena mikrostrip telah mendapatkan perhatian yang sangat besar dalam desain antena untuk sistem komunikasi nirkabel. Hal ini dikarenakan bentuknya yang kompak, kecil, ringan, serta mudah diintegrasikan dengan devais yang lain. Oleh karena itu, dalam skripsi ini dirancang antena mikrostrip dengan penambahan struktur Left-Handed Metamaterial (LHM) untuk tujuan miniaturisasi dan peningkatan gain. Frekuensi kerja antena dalam perancangan ini adalah 2,35 GHz dengan bandwidth 100 MHz. Finite Integration Technique (FIT) digunakan untuk melakukan analisis numeris terhadap desain antena. Hasil simulasi menunjukkan bahwa antena single elemen bekerja pada frekuensi 2,30 - 2,39 GHz dengan bandwidth 90 MHz (3,8 %), return loss -27,44 dB pada frekuensi tengah, dan gain 4,51 dBi. Sedangkan untuk antena array dua elemen bekerja pada frekuensi 2,29 - 2,42 GHz dengan bandwidth 128 MHz (5,4 %), return loss -28,98 dB pada frekuensi tengah, dan gain 8,2 dBi. Kemudian, dilakukan validasi antena dengan pengukuran di ruang anechoic chamber. Hasil pengukuran untuk single elemen menunjukkan bahwa antena bekerja pada frekuensi 2,26 - 2,38 GHz dengan bandwidth 114 MHz (4,89 %), return loss - 21,53 dB pada frekuensi tengah, dan gain 4,62 dBi. Sedangkan untuk antena array dua elemen, antena bekerja pada frekuensi 2,26 - 2,41 GHz dengan bandwidth 146 MHz (6,21 %), return loss -25,92 dB, dan gain 8,97 dBi. Dengan menggunakan struktur LHM, dimensi antena dapat dikurangi hingga 51 % untuk single elemen dan 39 % untuk array dua elemen. Bahkan untuk antena array dua elemen, gain antena dapat ditingkatkan hingga 8,97 dBi.

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Currently, the study of microstrip antenna has been great interest in most of antenna design for wireless communication due to its characteristics, such as light weight, compact, small, and easy to be integrated with other devices. This research will investigate a microstrip antenna which is constructed of Left-Handed Metamaterial (LHM) structure aiming at miniaturization and gain enhancement as well. In this research, a single element and a two element array antennas are proposed in order to have the resonant frequency at 2.35 GHz with the bandwidth 100 MHz. The antennas are numerically analyzed by using the Finite Integration Technique (FIT).

The simulation results show that the antenna works at 2.30 - 2.39 GHz with the bandwidth 90 MHz (3.8 %), return loss -27.44 dB at the center frequency and the gain 4.51 dBi for a single element. As for two element array antenna, the frequency operation is 2.29 - 2.42 GHz with the bandwidth 128 MHz (5.4 %), return loss -28.98 dB at the center frequency and the gain 8.2 dBi. The antennas are validated by the measurement that is conducted in an anechoic chamber.

The results show that the antenna works at frequency 2.26 - 2.38 GHz with the bandwidth 114 MHz (4.89 %), return loss -21.53 dB at the center frequency and the gain 4.62 dBi for single element. In addition, as for two element array antenna, it works at 2.26 - 2.41 GHz with the bandwidth 146 MHz (6.21 %), return loss -25.92 dB and the gain 8.97 dBi. Therefore, by using a LHM structure, the antenna dimension can be effectively reduced up to 51% and 39 % for single element and two array element, respectively. Moreover, the gain of two element array can be increased up to 8.97 dBi."

"bilangan prima dalam perkembangan ilmu komputer dan teori bilangan sangat perlu untuk menghasilkan suatu tingkat efektifitas dan efisiensi penggunaan perangkat keras. tools yang yang dapat digunakan untuk membangkitkan pola-pola urutan bilangan prima yang teratur. struktur bit-array merupakan metoda pengelompokan variabel-variabel yang berisi kumpulan data dengan tiap elemen data yang bertipe sama serta dapat digunakan dalam penyimpanan urutan dalam bilangan yang dihasilkan."

"In 2016, the mandatory use of biodiesel as a substitute fuel by up to 20%,as introduced by the Indonesian Ministry of Energy and Mineral Resources,forced vehicle manufacturers to invent suitable engines that would acceptbiodiesel. The use of biodiesel in such a large proportion is highly risky,particularly due to the formation of deposits in the combustion chamberengines. The previous method of fuel droplets are placed on a hot plateapproach produces deposits are slightly different from those generated by areal engine, therefore to obtain realistic deposits it is necessary to modifythis method so temperatures as hot as those in a real engine. In this study,the potential deposit formation of biodiesel fuel was examined by conductingthe deposition process and the evaporation of fuel on a stainless-steel plate(SS), which was placed in a closed space. Deposit characterization was carried outon a hot plate using Scanning Electron Microscopy (SEM). The test results showeddifferences in the structures of the deposits produced by biodiesel and dieselfuel; fine structures were seen in the former, while those of the latter wererougher and more porous. Deposit results that are similar to what is seen in areal engine will be very helpful for knowing the patterns, structures, and mechanismof the formation of deposits in such an environment."

"Beberapa tahun terakhir, studi mengenai antena mikrostrip memiliki ketertarikan yang besar pada rancang bangun antena untuk peralatan komunikasi nirkabel karena karakateristiknya yang menjanjikan, seperti ringan, kecil, dan mudah untuk diintegrasikan dengan peralatan lain. Skripsi ini akan menginvestigasi antenna mikrostrip segitiga yang dikombinasikan dengan struktur metamaterial guna mendapatkan karakteristik gain yang tinggi. Pada studi ini, sebuah elemen tunggal dan dua elemen susun yang ditumpuk dengan struktur metamaterial digunakan untuk menghasilkan frekuensi tengah pada 2,35 GHz dengan bandwidth yang mencukupi untuk aplikasi Long Term Evolution (LTE). Antena ini dianalisis secara numeric dengan Finite Integration Technique (FIT) pada simulasinya. Hasil simulasi menunjukkan bahwa antena bekerja pada frekuensi 2,29-2,39 GHz dengan bandwidth 96 MHz, return loss -25,06 dB pada frekuensi tengah, dan gain 3,2 dBi untuk single elemen. Pada dua elemen susun antena bekerja pada 2,31-2,38 GHz dengan bandwidth 64 MHz, return loss -14,57 dB pada frekuensi tengah, dan gain 5,4 dBi. Guna mendapatkan kinerja tinggi pada antena, dua elemen susun ditumpuk dengan struktur metamaterial. Hasil simulasi menunjukkan antena bekerja pada 2,29-2,39 GHz dengan bandwidth 101 MHz, return loss -22,39 dB pada frekuensi tengah, dan gain 9,1 dBi. Setelah simulasi terlaksana, antena-antena tersebut difabrikasi dan divalidasi dengan pengukuran yang dilakukan di Anechoic Chamber. Hasil pengukuran menunjukkan, dua elemen susun bekerja pada 2,31-2,37 GHz dengan bandwidth 60 MHz, return loss -18,93 dB pada frekuensi tengah, dan gain 5,02 dBi. Sebagai tambahan, struktur metamaterial dipasang di atas antena susun, antena bisa bekerja pada 2,24-2,35 GHz dengan bandwidth 111 MHz, return loss –11,98 dB pada frekuensi tengah, dan gain 8,9 dBi. Maka, penggunaan struktur metamaterial yang ditumpuk diatas antena, gain bisa ditingkatkan menjadi 8,9 dBi atau terjadi peningkatan 3,8 dBi.

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In recent years, the study of microstrip antennas have been great interest in most of antenna design for wireless communication devices due to it's promising characteristics such as light weight, compact, small, and easy to be integrated with other devices. This thesis will investigate a triangular microstrip antenna which is combined with metamaterial structure in order to obtain high gain characteristic. In this study, a single element and two-element array antenna with stacked metamaterial structure are proposed in order to generate the center frequency at 2.35 GHz with sufficient bandwidth for Long Term Evolution (LTE) application. The antenna is numerically analyzed by using the Finite Integration Technique (FIT) during simulation.

The simulation results show that the antenna works at 2.29-2.39 GHz with the bandwidth 96 MHz, return loss -25.06 at the center frequency, and the gain 3.2 dBi for single element. As for two-element array works at 2.312.38 GHz with the bandwidth 64 MHz, return loss -14.57 dB at the center frequency, and the gain 5.4 dBi. In order to obtain high performance of the antenna, the two-element array is stacked by a metamaterial structure. The simulation results show the antenna works at 2.292.39 GHz with bandwidth 101 MHz, return loss -22.39 dB at the center frequency, and the gain 9.1 dBi.

Having conducted the simulation, the antennas have been fabricated and validated by the measurement, which is performed in an Anechoic Chamber. The measurement results show that two-element array works at 2.312.37 GHz with the bandwith 60 MHz, return loss -18.93 dB at the center frequency, and the gain 5.02 dBi. In addition, when the metamaterial structure is installed on the top of the array, it works at 2.242.35 GHz with the bandwidth 111 MHz, return loss - 11.98 dB at the center frequency, and the gain 8.9 dBi. Therefore, by using a a metamaterial structure that is stacked on the top of the antenna, the gain can be increased up to 8.9 dBi or about 3.8 dB improvement."

"ABSTRACTPencitraan Terahertz THz yang merupakan diagnosis spektroskopik gelombang THz dikembangkan untuk mengatasi kekurangan-kekurangan teknik pencitraan yang ada. Salah satu teknik pencitraan THz adalah THz near field imaging. Namun, teknik ini memiliki kekurangan yaitu hanya mampu mencitrakan jaringan payudara dengan ketebalan 20 m. Untuk itu, antena susun mikrostrip rectangular patch dengan inset line dan rectangular slot 0.312 THz dirancang agar mampu mencitrakan jaringan payudara yang lebih tebal. Antena dengan 1x2 elemen ini bekerja pada frekuensi 0.312 THz, bandwidth 22.68 GHz, pola radiasi directional, gain 5.6 dB, beamwidth horizontal 86.5, beamwidth vertikal 47.1, dan polarisasi linier. Antena ini dapat mencitrakan jaringan payudara dengan tebal sebesar 2 mm dan jarak antara antena transmitter dan antena receiver sebesar 4.5 mm. Simulasi pencitraan THz dilakukan menggunakan perangkat lunak CST Microwave Studio. Objek yang akan dicitrakan adalah jaringan payudara yang dimodelkan dalam bentuk balok. Model jaringan payudara ini terdiri dari tiga tipe jaringan: fat, fibrous, dan tumor. Simulasi pencitraan THz dilakukan dengan menggunakan metode translasi dan pada dua kondisi: variasi frekuensi serta variasi jarak pada daerah near field dan far field. Pada simulasi pencitraan THz variasi frekuensi, hasil citra pada frekuensi 0.312 THz adalah hasil citra yang paling ideal secara kuantitatif dan kualitatif dibandingkan dengan hasil citra pada frekuensi 0.302 THz dan 0.322 THz. Pada simulasi pencitraan THz variasi jarak pada daerah near field, hasil citra pada jarak antena dan phantom 2.25 mm adalah hasil citra yang paling ideal secara kuantitatif dan kualitatif dibandingkan dengan hasil citra pada jarak antena dan phantom 1.25 mm dan 1.75 mm. Pada simulasi pencitraan THz variasi jarak pada daerah far field, hasil citra pada jarak antena dan phantom 3.50 mm adalah hasil citra yang paling ideal secara kuantitatif dan kualitatif dibandingkan dengan hasil citra pada jarak antena dan phantom 3.00 mm dan 4.00 mm.

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ABSTRACTTHz imaging, which is a THz wave spectroscopic diagnosis, was developed to address the shortcomings of existing imaging techniques. One of the THz imaging techniques is THz near field imaging. However, this technique has a shortcoming that is only able to image breast tissue with thickness of 20 m. Therefore, rectangular patch microstrip array antenna with inset line and rectangular slot 0.312 THz is designed to be able to image thicker breast tissue. The antenna with 1x2 elements work at a frequency of 0.312 THz, bandwidth of 22.68 GHz, directional radiation pattern, 5.6 dB gain, horizontal beamwidth of 86.5 degree, vertical beamwidth of 47.1 degree, and linear polarization. This antenna can image the breast tissue with thickness of 2 mm and the distance between the transmitter antenna and receiver antenna of 4.5 mm. THz imaging simulation is conducted by using CST Microwave Studio. The object to be imaged is breast tissue which is modeled in the form of a block. This breast tissue model consists of three tissue types fat, fibrous, and tumor. This imaging simulation is conducted by using the method of translation and on two conditions variation of frequencies and variation of distances in the near field and far field region. On the THz imaging simulation of variations of frequencies, the image result at the frequency of 0.312 THz is the most ideal image result quantitatively and qualitatively compared to the image results at the frequency of 0.302 THz and 0.322 THz. On the THz imaging simulation of variation of distances in the near field region, the image result at the distance between the antenna and phantom of 2.25 mm are the most ideal image results quantitatively and qualitatively compared to the image results at the distance between the antenna and phantom of 1.25 mm and 1.75 mm. On the THz imaging simulation of variation of distances in the far field region, the image result at the distance between the antenna and phantom of 3.50 mm are the most ideal image result quantitatively and qualitatively compared to the image results at the distance between the antenna and phantom of 3.00 mm and 4.00 mm."

"Semakin berkembangnya aplikasi penggunaan data AIS (Automatic Identification System) baik untuk pelacakan kapal, pemantauan lalu lintas laut, maupun untuk pengawasan maritime; membuat AIS mulai diaplikasikan pada satelit untuk mendapatkan coverage area yang lebih besar sehingga bisa melengkapi data AIS terestrial. Indonesia melalui Lembaga Penerbangan dan Antariksa Nasional (LAPAN), sudah mempunyai dua buah satelit mikro yang membawa misi AIS yaitu LAPANA2/ ORARI dan LAPAN-A3/IPB. Dan dalam rencana pembangunan satelitnya, LAPAN juga akan membuat satelit mikro lainnya yang juga membawa AIS sehingga pada akhirnya bisa mendapatkan data kapal di seluruh wilayah Indonesia secara near realtime. AIS menggunakan frekuensi VHF (161.975 MHz untuk AIS Class A dan 162.025 MHz untuk AIS Class B), sehingga dimensi antena yang digunakan besar. Hal ini akan menjadi permasalahan ketika satelit yang digunakan berplatform mikro, sehingga diperlukan miniaturisasi terhadap antena penerima AIS pada satelit. Permasalahan lain yang terjadi pada AIS berbasis satelit adalah adanya data collitions pada daerah yang mempunyai traffik padat. Pada tesis ini diusulkan sebuah antena yang dirancang sebagai antena penerima AIS untuk satelit mikro pada frekuensi 161.975 MHZ (AIS Class A) – 162.025 MHz (AIS Class B) yang memiliki dimensi cukup kecil dengan gain yang cukup tinggi. Teknik miniaturisasi yang digunakan adalah dengan mengunakan antena mikrostrip tipe meander dengan menambahkan bentuk metamaterial untuk meningkatkan performasinya. Hasil simulasi menunjukkan antena VHF berukuran 133.00 x 88.00 x 1.52 mm3 dengan gain 1.663dB. Antena yang dirancang memiliki polarisasi linier dan pola radiasi omnidirectional dengan beamwidth pada H-plane 88.5°. Hasil pengukuran menunjukkan frekuensi operasi pada 156.98-163.18 MHz dengan gain 0.18 dB. Dengan demikian antena ini dapat digunakan untuk menerima seluruh data AIS kelas A, data AIS kelas B dengan gain -9dB, serta VDES (VHF Data Exchange System). Miniaturisasi dengan teknik meander-line dan struktur metamaterial ini berhasil mereduksi dimensi sebesar 42%. Antena fabrikasi mempunyai pola radiasi omnidirectional dengan beamwidth pada E-plane 338.6° dan H-plane 88.26° sehingga ketika antena VHF ini diletakkan pada satelit, proyeksi antena pada permukaan bumi berkurang 50% dari sebelumnya sehingga dapat digunakan untuk mengurangi data coalition pada satelit.

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The development of AIS (Automatic Identification System) data usage applications, for tracking vessels, monitoring sea traffic, and for maritime surveillance; encourage AIS begin to be applied in satellites to get a larger coverage area so that it can complement terrestrial AIS data. Indonesia, through National Institute of Aeronautics and Space (LAPAN), already has two micro satellites that carry the AIS mission, namely LAPAN-A2/LAPAN-ORARI and LAPAN-A3/LAPAN-IPB. And in its satellite development plan, LAPAN will also create other micro satellites that also carry AIS so that in the end they can get near real-time ship data throughout Indonesia. AIS uses VHF frequencies (161,975 MHz for AIS Class A and 162,025 MHz for AIS Class B), so the dimensions of the antenna used are large. This will be a problem when the satellite is used on a micro platform, so it is necessary to miniaturize the AIS receiver antenna on the satellite. Another problem that occurs in satellite-based AIS is the presence of coaillition data in areas that have dense traffic. In this thesis, we propose an antenna designed as an AIS receiver antenna for micro satellites at a frequency of 161,975 MHz (AIS Class A) - 162,025 MHz (AIS Class B) which has a fairly small dimension with a high enough gain. The miniaturization technique used is to use a meander-type microstrip antenna by adding a metamaterial shape to improve its performance. The simulation results show that the VHF antenna measures 133.00 x 88.00 x 1.52 mm3 with a gain 1.663dB. The antenna is designed to have linear polarization, and an omnidirectional radiation pattern with a beamwidth on the H plane of 88.5 °. The measurement results show the operating frequency at 156.98-163.18 MHz with gain 0.18 dB. Therefore this antenna can be used to receive all AIS class A data, class B AIS data with a gain of -9dB, and VDES (VHF Data Exchange System). Miniaturization using the meander-line technique and the metamaterial structure was successful in reducing dimensions by 42%. Fabricated antenna also has an omnidirectional radiation pattern with a beamwidth in the E-plane 338.6° and the H-plane 88.26°. And when this VHF antenna is placed on a satellite, the antenna projection on the earth's surface is reduced by 50% from the previous one so that it can be used to reduce coalition data on the satellite."