TRANSITION FROM ANALOG TO DIGITAL RECORDERS FOR TELEMETRY AT THE WESTERN RANGE

Abstract

The transition of PCM recording from analog to digital recorders was completed at many test ranges more than a decade ago as marked by delivery of data on S-VHS tape, CD-ROM, DVD, ZIP disc, JAZ disc, 8mm tape and DLT tape for low rate data and D-1 cassettes for high rate data. Data then quickly began distribution via the internet and other networks. Analog recorders have remained a necessary legacy for the long transition to convert from analog to digital (PCM) data transmission from the test vehicles. However, the new digital recorder capabilities have removed this requirement to convert the transmissions from the test vehicle. Analog signal and predetection recording on digital recorders has been successfully demonstrated at costs below the existing analog recorders. Application of new techniques in a methodical transition program to the new digital recorders has proven the many benefits of recording wider bandwidths with excellent repeatability. Repeatability issues are primarily in the very low error sources of the processing system because the major analog error sources of the analog tape recorders, analog time code readers, analog demodulators, etc have been greatly reduced. This paper provides test results of recording higher signal rates and bandwidths of the new programs and describes the techniques and implementation through procedures of the Western Range transition from analog to digital recorders. Surprising results show predetection and analog signal recording costs are nearly the same as PCM recording costs due to the price of deliverable media with respect to mission recording requirements.