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Ultra-wideband (UWB) is a communications technology that operates on frequencies between 3.1 and 10.6 GHz and has a wide bandwidth. This paper aims to look at the radiation characteristics of the structure using the Theory Characteristic Mode on a rectangular antenna with bevel modifications at the end of the patch. It can be seen from the active mode at the appropriate frequency to validate the antenna performance results. It was found that the proposed antenna has four operational modes in the antenna design before modification and seven active modes in the antenna design after modification. The antenna is made of FR-4 material with a thickness of 1.575 mm and a dielectric constant of 4.3. The bandwidth in the error measurement is around 7 GHz and a frequency range of 3.18 - 10.915 GHz with an S11 value of less than -10 and a VSWR value of less than 2. Ultra-wideband (UWB) adalah teknologi komunikasi yang beroperasi pada frekuensi antara 3,1 dan 10,6 GHz dan memiliki bandwidth yang sangat lebar. Makalah ini bertujuan untuk melihat karakteristik struktur radiasi menggunakan Theory Characteristic Mode pada antena rectangular dengan modifikasi bevel diujung patch. Untuk validasi hasil performansi antena dapat dilihat dari mode aktif pada frekuensi yang sesuai. Ditemukan bahwa antena yang diusulkan memiliki 4 mode aktif pada desain antena sebelum modifikasi dan 7 mode aktif pada desain antena sesudah modifikasi.. Antena terbuat dari bahan FR-4 dengan ketebalan 1,575 mm dan konstanta dielektrik 4,3. Bandwidth yang dicapai pada pengukuran adalah disekitar 7 GHz dan rentang frekuensi 3,18 - 10,915 GHz dengan nilai S11 kurang dari -10 dan nilai VSWR kurang dari 2.

This paper presents a Microstrip Antenna Analysis for the ISM Band with a circular patch design with a radius of 17 mm at a frequency of 2,400 – 2.484 GHz. The fabricated array antenna has a very compact width and length of 9.5 x 7.5 cm each. Therefore, an increase in bandwidth on the monopole antenna can be applied to the array arrangement. So to get the best antenna design, two optimizations of antenna size changes are carried out during the simulation: optimization of patch radius and slot length. The radius variation is used to shift the frequency range and slot length for impedance matching, as seen from the S11 value of less than -10 dB. From each change, the best results are taken. Experiments get the best antenna simulation results and are then fabricated. From the measurement results on the fabricated antenna, the lowest S11 value is -19.602 dB, and the gain is 3.52 dBi. The slot technique's optimization process has successfully shifted the frequency to approximately 100 MHz and increased the bandwidth by about 5% or 40 MHz.

Untuk meningkatkan kualitas tangan bionik yang digunakan oleh beberapa penyandang disabilitas, diperlukan inovasi baru. Dengan menerapkan IoT dalam pengembangan tangan bionik dapat memudahkan pasien untuk mendapatkan informasi, seperti monitoring kapasitas baterai, umur tangan bionik dan kesehatan tangan bionik. Sehingga diperlukan adanya komponen yang mampu mengirimkan informasi tersebut. Dalam makalah ini, kami menyelidiki antena Meander Planar Inverted F Antenna (PIFA) pada frekuensi 915 – 925 MHz yang kompatibel dengan teknologi Sigfox atau LoRa IoT. Antena dirancang memiliki karakteristik miniatur sehingga tidak mengganggu komponen lain saat ditanamkan di tangan bionik dan melengkung sehingga dapat mengikuti bentuk lengkung tangan bionik. Teknik miniatur yang digunakan adalah teknik meander dan teknik konformal digunakan untuk memberikan efek lengkung pada antena. Perancangan dilakukan dengan sangat sistematis dengan mengefektifkan langkah-langkah menggunakan metode Design of Experiment. Terbukti hanya membutuhkan 6 langkah untuk mendapatkan hasil yang sesuai dengan spesifikasi. Hasil simulasi menunjukkan nilai S11 sebesar -21 dB, frekuensi resonansi 924,9 MHz, bandwidth 13,5 MHz, gain -23,34 dBi dan pola radiasi omnidirectional.

This paper presents the analyzed Monopole Antenna for Ultrawideband with a rectangular patch design using bevel technique at a frequency of 3.1 – 10.6 GHz. The fabricated antennas with dual bevel angles have a very compact width and length of 40 mm x 33 mm respectively and a groundplane width of 13 mm. To get bandwidth improvement on monopole antennas can be applied to the bevel angle on the patch. So, to get the best antenna design, 3 optimizations of antenna size changes were carried out during the simulation, that is optimization of patch length, patch width and bevel angle. Variation of patch length and width is used to change the frequency range and variation of bevel angle to increase bandwidth. From each change, the best result is taken. The experiment obtained the best simulation result of antenna and then fabricate it. From the measurement results on the fabricated antenna, the lowest S11 value is -24.6 dB, gain 2.6 dBi at a frequency of 5 GHz and radiation pattern is omnidirectional. The optimization process using the bevel technique has been proven to be successful in shifting the frequency range by around 600 MHz and increasing the bandwidth by about 4% or 30 MHz.

This study aims to assist farmers in monitoring soil nutrients, especially phosphorus. To measure the phosphorus content of paddy soil, the TCS3200 converter, as an intelligent sensor, was applied. The geographical information system (GIS) was also involved in this research to map the phosphorus content. In addition, the Naïve Bayes method was applied to classify lowland soil phosphorus status. The result of this study indicated that the Naïve Bayes algorithm could classify lowland soil phosphorus status with a probability of 0.34 for moderate phosphorus conditions and 0.66 for high phosphorus conditions. The sample testing results showed that the error rate was 3% and the success rate was 97%. Testing with a phosphorus-measuring instrument can be carried out by mapping the soil phosphorus status with the ArcGIS software, whereby seven points of medium-phosphorus-status paddy soil and 13 locations of high-phosphorus-status soil samples were determined. This research thus successfully mapped the soil phosphorus.

This paper presents a PIFA (Planar Inverted F Antenna) analysis with a meander design mounted on bionic hand using conformal technique at a frequency of 2.4 GHz. In the process of obtaining the best design of antenna, the DOE (Design of Experiment) method was used. The DOE method allows the designer to obtain the significant factors on the design parameters that affect the response value. The response values are S 11 , resonant frequency and bandwidth. By using DOE method, it only required 3 tuning processes to obtain the best antenna design with the addition of bionic hand material. The experiment obtained the best simulation result of antenna with the addition of bionic hand that resonates at a frequency of 2.441 GHz with value of S 11 of -21.1 dB, a bandwidth of 43.2 MHz and a gain of -6.4 dBi.

Characteristic mode analysis (CMA) allows systematic antenna design. This method provides resonant frequency and current distribution modes of antenna structure. This feature can be utilized also to analyze the cause of problem of an antenna and to suggest solution to the problem. This paper utilizes CMA to circular microstrip antenna. The problem of mismatched-impedance can be identified. Insertion of slots to the circular patch has successfully separates the two lowest mode resulting in bandwidth enhancement. Measurement shows that the slotted circular microstrip antenna is matched at 2,375–2,540 MHz and has directional radiation pattern with front-to-back ratio of 15 dB.

Wi-Fi (Wireless Fidelity ) merupakan sebuah teknologi yang memanfaatkan peralatan elektronik untuk bertukar data secara nirkabel. Dalam sistem komunikasi wireless bagian terpenting untuk mengoptimalkan kinerjanya adalah antena. Mikrostrip adalah salah satu jenis antena yang praktis mempunyai ukuran dan dimensi yang sederhana dan mudah difabrikasi. Pada penelitian ini dibahas bagaimana desain dan analisa antena mikrostrip dengan bentuk patch sirkular dengan spesifikasi frekuensi kerja 2,400 – 2,484 GHz menggunakan substrat FR-4 dengan ketebalan 1,6 mm dan = 4,3. Teknik pencatuan yang digunakan adalah dengan teknik microstrip line feed . Perancangan dan simulasi antena mikrostrip dilakukan menggunakan software CST Studio Suite 2016. Antena yag dirancang juga dianalisa menggunakan Characteristic Mode Analysis (CMA). Hasil yang ditampilkan berupa grafik mode-mode arus pada modal significance. Dihasilkan sebanyak dua mode yang berhimpit untuk desain patch A pada frekuensi 3081 MHz dan terjadi perubahan untuk desain patch B, dimana kedua mode berpisah dan bergeser, mode 1 bergeser ke frekuensi 2406 MHz sedangkan mode 2 bergeser ke frekuensi 1889 MHz. Dari antena mikrostrip yang telah difabrikasi dilakukan pengukuran beberapa nilai parameter yaitu, S 11 sebesar -21,13 dB, VSWR 1:1,19, rentang frekuensi 2,37 – 2,54 GHz, pola radiasi directional dan gain sebesar 2,15 dBi.