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The growth of aviation activities at I Gusti Ngurah Rai International Airport, Bali, has led to the rapid development of surrounding areas, potentially obstructing protected airspace. Obstacles on the approach surface of Runway 27 have become a critical concern, particularly for precision approach Category II (CAT II) operations, which require obstacle-free approach areas. This study aims to analyze obstacles within the approach area of Runway 27 and develop effective control strategies. Using a descriptive qualitative approach, data was collected through field observations, interviews, and documentation studies. The analysis follows the Obstacle Limitation Surfaces (OLS) standards according to ICAO and national regulations. The findings reveal obstacles such as mangrove vegetation, antennas, and ship activities in the Benoa Harbor area, which are located within the approach surface and could potentially impact the OLS limits. While these obstacles generally comply with existing regulations, their proximity to the threshold may reduce the safety margin of flight operations and limit CAT II implementation on Runway 27. This study proposes technical, operational, regulatory, and preventive strategies to improve obstacle control, enhancing aviation safety and ensuring the readiness for CAT II operations at the airport.

Penelitian ini bertujuan untuk merancang dan merealisasikan antena mikrostrip patch berbentuk segitiga (triangular) yang bekerja pada frekuensi 1800 MHz, sebagai penguat jaringan internet di kawasan Kebun Raya Balikpapan. Lokasi tersebut diketahui memiliki kualitas sinyal yang kurang baik untuk beberapa provider. Antena yang dirancang menggunakan dua konfigurasi, yaitu MIMO 8x8 dengan teknik pencatuan langsung dan array 8x1, yang kemudian disimulasikan menggunakan CST Studio Suite 2019 dan diuji performansinya menggunakan metode Speedtest. Hasil simulasi menunjukkan bahwa antena 8x8 memiliki nilai VSWR sebesar 1,50, return loss -12,96 dB, dan gain 4,06 dBi dengan pola radiasi omnidirectional. Sementara itu, konfigurasi 8x1 array menunjukkan nilai VSWR 1,24, return loss -19,21 dB, dan gain 6,46 dBi, juga dengan pola radiasi omnidirectional. Hasil pengujian di lapangan dengan tiga kondisi tanpa antena eksternal, antena MIMO dan antena array 8x1 didapatkan hasil bahwa antena array 8x1 memberikan kecepatan unduh tertinggi mencapai 17,227 Mbps, unggah 4,072 Mbps, Jitter 34,9 ms  dan packet loss 14,18 % sedangkan antena MIMO 8x8 memberikan kecepatan unduh tertinggi mencapai 13,77 Mbps, unggah 2,462 Mbps, Jitter 49,9 ms  dan packet loss 18,43%. Kesimpulannya, kedua jenis antena eksternal yakni MIMO 8x8 dan array 8x1 mampu meningkatkan performa jaringan secara signifikan dan dapat menjadi solusi efektif untuk daerah dengan sinyal lemah. Antena ini diharapkan dapat memberikan kontribusi terhadap akses internet yang lebih stabil di area public yang sangat luas.

This study presents a machine learning approach for predicting the dimensions of microstrip antenna slots based on antenna performance parameters such as frequency, gain, directivity, return loss (S11), radiation efficiency, and VSWR. A two-phase methodology was employed. In the first phase, ten regression algorithms were evaluated, and Random Forest was identified as the most effective model based on Mean Absolute Error (MAE) and R-squared (R²) scores. In the second phase, hyperparameter tuning was conducted using Grid Search to further improve the model’s performance. The optimized Random Forest model demonstrated consistent improvements in predictive accuracy, with R² values increasing across all output variables. These results indicate that the combination of regression-based modeling and systematic hyperparameter tuning is effective for capturing complex relationships in antenna design tasks. The proposed approach offers a promising data-driven alternative for geometric prediction in microstrip antenna development, particularly when analytical models are insufficient.

The objective of this project is to develop cost-effective antenna systems. The study utilized AutoCAD 2006 for data analysis and visualization. This article provides a detailed examination of various antenna systems, including cable/wire, log-periodic, array, helical, and aperture antennas. The research also explores several parameters related to antenna systems, such as effective length, antenna gain and directivity, active aperture, bandwidth, polarization, input impedance, power gain, radiation efficiency, radiation pattern, and radiation intensity. The main goal is to identify the challenges in designing cost-effective antenna systems for reliable communication. These challenges include design issues, contract management difficulties, fluctuating material prices, inaccurate estimations, limited wireless communication technology, and financial constraints. The study examines a wavelength range from 16.7 to 120, corresponding to distances from 10,000 km to 120,000 km. The findings show that at a frequency of 600 MHz, a wavelength of 16.7 units covered a distance of 10,000 km. Similarly, at 750 MHz, a wavelength of 53.3 units covered 40,000 km, and at 850 MHz, a wavelength of 94.1 units spanned 80 km. At 1000 MHz, a wavelength of 120 units covered 120,000 km. This study offers valuable insights into the design of cost-effective antenna systems and provides an understanding of the factors that influence their performance in practical communication scenarios.  

Radio is a mass media that is still used by many people as a means of communication, such as listening to songs, informing news and others. One of the radio stations that still exists and is developing to this day is Radio Republik Indonesia, which is overseen by the government, which can now be accessed via available radio and websites so that it makes it easier for listeners to listen to and watch the news and can be accessed anywhere. The author conducted research at Radio Republik Indonesia in the Central Jakarta section using qualitative research methods where the author went directly to the field or observed and interviewed as well as assisting with literature studies. The aim of conducting this research was to find out how the broadcasting system and radio supporting equipment at Radio Republik Indonesia Jakarta . So the results obtained are in the form of a radio broadcasting system at Radio Republik Indonesia using two broadcasting systems, namely audio and visual as well as supporting equipment used in the form of Microphones, Mixers, OB – Van, MCR, Transmitter, STL and Antenna.

This research aims to identify the values of mutual cooperation character found in the Adit and Sopo Jarwo animation as one of the media to be used in strengthening the national identity of elementary school students. The method used in this research is qualitative with content analysis method, and data collection techniques include literature study, documentation, and data analysis. Based on the results of the research conducted, it was found that in the Adit and Sopo Jarwo animated film, there are 7 values of mutual cooperation character, which are helping each other, appreciating teamwork, solidarity, commitment to collective decisions, empathy, anti-violence, and a voluntary attitude. These values of mutual cooperation character appear in 11 episodes of the Adit and Sopo Jarwo animation, namely in the episodes of the father's lost wallet, the father's wallet is still lost, Jarwo's theft, Adit wins, the confusing umbrella motorcycle taxi, Adit's flu, Jarwo's sadness, getting caught up in the antenna service, kite competition making everyone fly, Jarwo's surprise, Adel's whereabouts, patrol duties like courage tests, and visiting siblings making everyone feel honored. Furthermore, the Adit and Sopo Jarwo animation can be used as a learning tool in strengthening the national identity because this animation contains scenes that are in line with the development of mutual cooperation character as a way to strengthen the national identity.

Orbital perturbation is a phenomenon in which the orbit of a satellite changes due to one or more external influences such as an anomaly in the Earth's gravitational distribution, gravitational disturbances from the moon, meteor impacts or other objects, or solar radiation pressure. These maneuvers use small rockets (thrusters) that are on the satellite body and the direction is set according to the correction direction. Ignition of these small rockets will consume fuel brought by satellites from Earth as a provision. Communications satellites have demonstrated their capabilities since the last three decades. that the communication satellite mission in the 60s was an alternative point-to-point transmission between continents, due to its ability to see approximately one third of the earth's surface from the geostationary orbit altitude just above the equator.

Antenna mikrostrip planar pita lebar dengan teknik defected ground structure (DGS) telah disajikan. Ukuran antenna yang dirancang adalah 56 mm x 47 mm x 1,6 mm. Antenna dengan teknik DGS ini memiliki parameter return loss sebesar -24,8 dB dan -19,1 dB yang beroperasi masing-masing pada frekeunsi kerja 5,57 GHz dan 3,51 GHz. Antena ini menyediakan persentase bandwidth 52%, mulai dari 3,4 GHz hingga 5,9 GHz dengan penguatan konstan. Antenna ini digunakan untuk aplikasi ultra wideband (UWB) dan komunikasi nirkabel modern seperti wifi, WLAN dan Wimax.

The innovation of the robot cars today is moving very fast. The robot car is capable of being driven without using manual remote controls. One form of technological development in robot car control is by using hand gestures. The microcontrolle placed in the palm of the hand will read the direction of movement of our hands, then the instructions are transmitted to the robot car.  The transmission system used in the microcontrolled circuit in the palm of the hand and the receiver circuit inside the robot car must be properly attached. This is influenced by the quality of programming language levels and the arduino mini pro and MPU-6050 circuits. Hand gesture directional readings are able to be easily readable and directly transmitted by the NRF24L01 module via radio waves. The response power of the robot car in receiving hand-move instructions can be received as far as 45 m. In addition to using a good arduino mini pro, the addition of antenna modules will also increase the quality and distance of the connection is getting farther..