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Bandung District is one of crop provider for West Java Province. About 31.158,22 ha is used for crop. However, some of them are not maintained well due to lack of vegetation map information. Local authority has tried to map the vegetation in their area by using free license satellite images, and aerial images from Unmanned Aerial Vehicle (UAV). Despite both images being able to provide large plantation area images, both are unable to classify the vegetation type in those images. Telkom University with Bandung Agriculture Regional Office (Dinas Pertanian Kabupaten Bandung) has conducted joint research to develop algorithm based on 50-layer residual neural network (ResNet50) to classify the vegetation type. The input is of this algorithm is primarily aerial images are captured from different type, height, and position of crops. Seven different ResNet50 configurations have been set and simulated to classify the crop images. The result is the configuration with resized images, employing triangular policy of cyclic learning rate with rate 1.10−7 – 1.10−4 comes out as the best setup with more than 95% accuracy and relatively low loss.

Multiple Input Multiple Output (MIMO) is a key technology that plays an important role in achieving the 5G requirement due to its capability to increase channel capacity. However, the increase of channel capacity is influenced by several aspects such as mutual coupling. Many methods are done to decrease the mutual coupling effect such as polarization arrangement of the MIMO antennas. This study on the polarization arrangement of a circular patch MIMO antenna at 3.5 GHz was performed. Four elements of the MIMO antenna are arranged with several polarization configurations both in Co-Polarization and Cross-Polarization. Both simulation and measurement results showed that MIMO with Co-Polarization has a slightly wider bandwidth equal to 295.25 MHz compared to Cross-Polarization with a bandwidth of 274.63 MHz, due to better return loss performed by the former. However, from the mutual coupling perspective, it is observed that MIMO with Cross-Polarization can reduce the mutual coupling from -17.6676dB into -22.462 dB compared to Co-Polarization with the same element distance.

Kapasitas kanal adalah parameter penting sistem komunikasi nirkabel. Suatu sistem komunikasi diharapkan mampu menyediakan kapasitas kanal yang tinggi. Sistem dengan Multipe Input Multiple Output (MIMO) antenna mampu menyediakan kapasitas kanal yang tinggi. Pada penelitian ini, kinerja sistem MIMO diamati dengan penerapan Scalable Orthogonal Frequency Division Multiple Access (SOFDMA). Teknik Adaptive Modulation and Coding (AMC) serta Adaptive MIMO Switching (AMS) juga diterapkan pada sistem ini. Jumlah subcarrier yang digunakan dalam SOFDMA tersebut yaitu 128 dan 2048. Kinerja sistem yang diamati yaitu kapasitas kanal dengan variasi kecepatan pengguna. Variasi pergerakan pengguna meliputi 0 km/jam dan 120 km/jam. Kapasitas kanal sistem dengan kombinasi teknik AMC dan AMS dapat mencapai 419,5115 Mbps saat kecepatan pengguna sebesar 0 km/jam. Saat kecepatan pengguna sebesar 120 km/jam, kapasitas kanal sistem dapat mencapai 23,9820 Mbps