DESAIN PROTOKOL MEDIA ACCESS CONTROL (MAC) UNTUK SISTEM KOMUNIKASI KOOPERATIF PADA JARINGAN AKUSTIK BAWAH AIR

Implementasi jaringan sensor nirkabel pada bawah air bisa dilakukan dengan menggunakan sistem komunikasi akustik. Sistem komunikasi akustik adalah sistem komunikasi yang gelombang pembawanya berupa gelombang suara. Sistem komunikasi akustik mempunyai tantangan yang unik bila dibandingkan dengan sistem komunikasi radio atau optik di udara, diantaranya adalah kecepatan perambatan gelombang suara yang lambat yang mengakibatkan durasi propagasi menjadi tinggi dan sempitnya lebar pita yang tersedia. Disamping itu, bila sistem komunikasi akustik bawah air dikehendaki untuk jaringan sensor nirkabel yang pada umumnya terdiri atas banyak node, maka diperlukan pengaturan penggunaan kanal yang biasanya disebut sebagai protokol Media Access Control (MAC). MAC yang sudah ada untuk jaringan komunikasi nirkabel di udara tidak bisa langsung digunakan di jaringan bawah air karena tingginya delay propagasi gelombang akustik. Perlu desain unik agar bisa sesuai dengan karakteristik propagasi gelombang akustik di air. Oleh karena itu, untuk mengatasi tantangan jaringan akustik bawah air, diusulkan protokol Cooperative MAC for Underwater (CoopMAC-U). Dari hasil simulasi menunjukkan bahwa CoopMAC-U memberikan throughput yang lebih bagus dibandingkan dua protokol yang lain, yaitu ALOHA dan MACA-U (Multiple Access Collision Avoidance for Underwater)

Further simulation testing in CoopMAC-U for underwater acoustic sensor networks

In order for underwater wireless sensor networks to communicate more efficiently, MAC protocols are needed to control the use of acoustic channels. With the high propagation delay and the limited bandwidth available on the acoustic channel, a specially designed MAC protocol is needed for UWASN (Underwater Acoustic Sensor Networks). In this research, the adaptation of Cooperative MAC for underwater (CoopMAC-U) will be further studied to test the protocol performance. In the previous research, CoopMAC-U was simulated yet the fairness of the transmission was not simulated and tested. In this research, CoopMAC-U will be studied further and improved. The simulation result shows that the Improved CoopMAC-U protocol produces better-normalized throughput than the initial version of CoopMAC-U. The protocol is also proven that it is backward compatible between conventional mode and cooperative mode. For offered load greater than 0.2, both the initial version of CoopMAC-U and the Improved CoopMAC-U result in stagnant normalized throughputs but the improved ones double the value of the initial version

Antarmuka Mikrokontroller IoT (ESP32) Dengan USB Host max3421e

Electronic equipment made using old technology or electronic equipment in the entry-level category has not been supported by networking equipment, so for the data communication process, the microcontroller requires interfacing facilities that are in accordance with the electronic equipment used, such as a USB port. With the microcontroller that supports IoT, it allows electronic equipment to communicate over the network. An IoT microcontroller such as the ESP32 is equipped with a WiFi feature but is not equipped with a USB controller feature, while the USB Host max3421e supports the communication process using SPI, so that those two microcontrollers can be used to form an interface using the SPI bus. This interface can be applied to electronic equipment with old technology and entry level electronic equipment for wireless communication. For the needs of making an interface between the ESP32 and max3421e, a software was developed by analyzing the SPI features of the ESP32 and the USB protocol according to the USB device state diagram. The results obtained are the handshake process between systems developed with USB devices in the Low-Speed ​​and Full-Speed ​​categories such as printers, flashdisk, bluetooth mouse and external hard disk, and the device descriptor data of each device tested can be read properly