Development of earth stations: Portable earth station. Data collection system

Abstract

It is planned to verify the on-orbit antenna patterns in the framework of the electrical characteristics verification test for the Engineering Test Satellite 8 (ETS-8) on-board antenna by using electric power data measured at portable terminals located at multiple points. The data collection system measures the receiving signal power at each portable terminal and delivers them to the host terminal. The system is designed to minimize operation at the portable terminals and to have all terminals controlled by the host terminal. It is composed of portable terminals with wireless communications, like the Personal Handyphone System terminal or cellular phone terminals (five terminals are planned), and a host terminal located at the Kashima Space Research Center of the Communications Research Laboratory. Commands and data are transferred via the Internet using an Internet Service Provider. Data measurement is performed at each portable terminal based on the commands generated at the host terminal. The frequency and power of the received signals with GPS times are measured at a maximum rate of about four samples per second. Real-time data collection for the host terminal from each portable terminal and visualization of the data enables the operator of the host terminal to immediately verity the data. Additionally, the host terminal can monitor the state of the equipment of the portable terminals: this is called the 'health-check' function. It can also set the state of the equipment in the portable terminal.