Tele-X - The first step in a satellite communications system for the Nordic countries

The development and design of Tele-X, an experimental TV and telecommunications satellite to be launched in 1986 by Sweden, Norway, and Finland, are discussed. The history of the cooperative R&D venture is traced from the beginning of Nordsat studies in 1974 through the 1977 WARC frequency and orbit allocations and the initiation of the Viking research-satellite program and the Tele-X program in the late 1970s. The Tele-X spacecraft and its payload are modified versions of the TV-Sat/TDF-1 satellite design being completed by France and the FRG. Primary services to be provided include TV (using two 230-W TWTA transponders in the 18/12-GHz bands) and data/video communication (using one wide-band and one narrow-band transponder in the 14/12-GHz bands and serving a fully switched digital network at 64 kbit/sec and 2 Mbit/sec). Experimental transmissions at 8, 34, and 140 Mbit/sec will also be undertaken. Block diagrams, drawings, tables of performance data, and a coverage map are included.