Development and Fabrication of a Compact Integrated RF-Head for Inmarsat-M Ground Terminal

This paper describes the design, performance and fabrication of a compact and low cost RF-Head for Inmarsat-M applications. The RF-Head is part of a portable satellite communication terminal called "Caryphone". "Caryphone" supplies phone and fax services to the customer. The "Caryphone" terminal has been approved by Inmarsat on Augrust 1995. Up to date around 300 terminals have been manufactured. The RF-Head includes a receiving and transmitting channels, receiving and transmitting synthesizers, RF-Controller, Modem and a DC supply unit. The RF-Head size is 30×20X2.5 cm and weighs less than 1 Kg. The transmitting channel may be operated in high power mode or in low power mode to transmit 10W or 4W respectively. The output power level and the RF-Head vent is automatically controlled by the RF controller The noise figure of the receiving channel is better than 2.2 dB including 1dB diplexer losses The total gain of the receiving channel is 76dB. Surface Mount Technology is employed to fabricate the RF-Head.