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Bevan, R.

Publications and source records attributed to Bevan, R..

Sequence-of-events-driven automation of the deep space network

In February 1995, sequence-of-events (SOE)-driven automation technology was demonstrated for a Voyager telemetry downlink track at DSS 13. This demonstration entailed automated generation of an operations procedure (in the form of a temporal dependency network) from project SOE information using artificial intelligence planning technology and automated execution of the temporal dependency network using the link monitor and control operator assistant system. This article describes the overall approach to SOE-driven automation that was demonstrated, identifies gaps in SOE definitions and project profiles that hamper automation, and provides detailed measurements of the knowledge engineering effort required for automation.

Hill, R., Jr.↗

Sequence-of-Events-Driven Automation of the Deep Space Network

In February 1995, sequence-of-events (SOE)-driven automation technology was demonstrated for a Voyager telemetry downlink track at DSS 13. This demonstration entailed automated generation of an operations procedure (in the form of a temporal dependency network) from project SOE information using artificial intelligence planning technology and automated execution of the temporal dependency network using the link monitor and control operator assistant system. This article describes the overall approach to SOE-driven automation that was demonstrated, identifies gaps in SOE definitions and project profiles that hamper automation, and provides detailed measurements of the knowledge engineering effort required for automation.

Hill, R., Jr.↗

The Advanced Receiver II telemetry test results at Goldstone

The telemetry performance of the Advanced Receiver II (ARX-II) in tracking and demodulating signals from various deep space missions is described. The tests were performed at Goldstone, and the spacecrafts tracked were Pioneer 10, Pioneer 11, Voyager 2, Magellan, and the International Cometary Explorer (ICE). These missions present a broad range of operating conditions to test the ARX-II in terms of signal-to-noise ratio (SNR) and the symbol rate of the received signal.

Sadr, R.↗

The advanced receiver 2: Telemetry test results in CTA 21

Telemetry tests with the Advanced Receiver II (ARX II) in Compatibility Test Area 21 are described. The ARX II was operated in parallel with a Block-III Receiver/baseband processor assembly combination (BLK-III/BPA) and a Block III Receiver/subcarrier demodulation assembly/symbol synchronization assembly combination (BLK-III/SDA/SSA). The telemetry simulator assembly provided the test signal for all three configurations, and the symbol signal to noise ratio as well as the symbol error rates were measured and compared. Furthermore, bit error rates were also measured by the system performance test computer for all three systems. Results indicate that the ARX-II telemetry performance is comparable and sometimes superior to the BLK-III/BPA and BLK-III/SDA/SSA combinations.

Hinedi, S.↗

Digital Doppler extraction demonstration with the advanced receiver

A digital Doppler extraction demonstration with the Advanced Receiver 2 (ARX 2) tracking Pioneer 10 and Voyager 2 is described. The measured results are compared with those of the Block 4 receiver that was operating in parallel with the ARX 2. It is shown that the ARX 2 outperforms the Block 4 receiver in terms of Allan variance of the Doppler residuals, the amount of which depends on the scenario of interest.

Hinedi, S.↗