Data Processing and Information Transmission for Space

This paper reviews and predicts the roles that data processing and information transmission have played, and will play, in space. The trend toward digital transmission is shown to be a result of increasing requirements for precision, reliability, high information rates, and long paths. Thus, data processing and transmission techniques appear to be converging rapidly, both because of the advantages of digital communication systems and because of the predicted weight and volume reductions for computer equipment. Many improvements in transmission efficiency will result from this merging of techniques, notably in the areas of data compaction and computer-controlled adaptive communications. The problem of maintaining a satisfactory SNR in spite of the signal loss from space attenuation is reviewed. General trends in the techniques designed to improve this ratio are reported and several promising developments are emphasized. Among these are the use of signals with large bandwidth-time products, maser amplifiers, and a novel telemetry system which provides high antenna gain with a greatly reduced orientation problem and eliminates spacecraft transmitting equipment by transferring it to earth.