Pre-operational tests of high-speed /56 kbps/ transmission over MARISAT

Results are presented for tests conducted to determine the performance characteristics of the US MARISAT shore stations, which provide ship-to-shore data transmission at 56 kbps. It is found that three distinct categories of error mechanisms are present in the system: random errors, longer bursts from loop slips, and still longer bursts associated with losses of signal. These results indicate that throughput, not bit error rate, be used to define system performance. It is concluded that by paying proper attention to all system elements, very high throughput can be maintained under a wide variety of operating conditions.