REG NASA-LLIS-2157-2010 Lessons Learned Network Radio Frequency (RF) Compatibility Testing.pdf

1、Lessons Learned Entry: 2157Lessons Learned Entry: 2157Lesson Info:a71 Lesson Number: 2157a71 Submitting Organization: MSFCa71 Submitted by: Barbara Cobba71 POC Name: Barbara Cobba71 POC Email: barbara.cobbnasa.gova71 POC Phone: 256-961-7060Subject: Network/Radio Frequency (RF) Compatibility Testing

2、Abstract: When conducting any type of compatibility testing, no matter how repetitive, it is important to always follow written procedures and best engineering practices even though those procedures have been run many times before. Not paying attention to detail and losing track of the hardware conf

3、iguration can lead to confusion and a complete failure of the test.Description of Driving Event: The Network/Radio Frequency (RF) Compatibility Test was run to prove that the NASA ground network would work with the Hinode (Solar-B) satellite. At the time of the test, it was thought that the best way

4、 to prove the NASA ground stations would be able to communicate with the Japanese-built satellite was to use the GSFC testing equipment designed specifically for this scenario. Typically, the test racks are packed, sent to wherever the satellite is being built, and tested there. In this case, testin

5、g took place in Japan. This resulted in a number of problems: a71 During the test preparation timeframe, it was difficult to obtain information on the status of the test. a71 The shipment of the testing racks and power converters was coordinated very late, leading to confusion and frustration. a71 T

6、he power converters may have played an important part in subsequent anomalies during the testing and should have been more thoroughly researched. a71 The testing racks were antiquated, leading to difficult situations during the testing. a71 Changes were made to the test requirements without a discus

7、sion being held with the entire Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Lessons Learned Entry: 2157group; and consequently, they did not reflect the correct Solar-B requirements. a71 A Test Procedure Review was conducted the night before the

8、test, and only after the MSFC Project Office insisted. a71 The test procedures should have been placed under configuration control and followed during the testing. a71 At the test site, the time given for configuration and verification of the test hardware was inadequate; and the racks were taken ap

9、art and re-integrated using photographs. a71 Because there were no setup and verification procedures to follow, setup problems led to a loss of 2 days of testing time. a71 Uplink commands for the RF Compatibility Test were not loaded beforehand for efficiency. Loading the commands during the test wa

10、sted the engineers time. a71 Troubleshooting during the testing did not follow standard engineering practices or another type of logic flow. During the troubleshooting, the engineers were unable to return the test racks to a known configuration because the configuration changes had not been tracked

11、as the troubleshooting progressed. a71 As the testing and troubleshooting progressed, and even after the testing was complete, no one accepted responsibility for the schedule delays, problems during the test, or failure of the test. After the failed test, another test was performed, this time using

12、a flight satellite with the same transponder and telemetry system as the one being tested on the ground station. The MSFC Project Office had originally suggested this test, but it was rejected. This test was easily passed with no complications.Lesson(s) Learned: If conducting RF compatibility testin

13、g in the U.S., adequate planning must be done to prevent the problems that were encountered with shipping, outdated equipment, configuration control of test procedures and equipment, troubleshooting, and assigned responsibilities. If conducting the same testing overseas, the following feasibility st

14、udy could be performed: If there is another satellite operating with the same transponder and telemetry system as the one being tested, the ground station could track the orbiting spacecraft to provide data for the characterization of the downlink telemetry performance and to verify station configur

15、ation and telemetry data handling in support of the test spacecraft. This was done to finalize the incomplete RF Compatibility Test for Solar-B.Recommendation(s): Always plan adequately for compatibility testing. Always follow best engineering practices during testing: review, manage the configurati

16、on, and follow all procedures in the test documentation (e.g., setup and verification procedures, test procedures, test commands). Perform any setup activities that can be done before the test to save time during the test. Document results of each step of the test, Provided by IHSNot for ResaleNo re

17、production or networking permitted without license from IHS-,-,-Lessons Learned Entry: 2157including any unexpected results, malfunctions, anomalies, or hardware/software changes.Evidence of Recurrence Control Effectiveness: N/ADocuments Related to Lesson: N/AMission Directorate(s): a71 ScienceAddit

18、ional Key Phrase(s): a71 Missions and Systems Requirements Definition.Configuration control and data managementa71 Missions and Systems Requirements Definition.a71 Program Management.Risk managementa71 Systems Engineering and Analysis.a71 Safety and Mission Assurance.Maintenancea71 Safety and Missio

19、n Assurance.Configuration Change Controla71 Safety and Mission Assurance.a71 Mission Operations and Ground Support Systems.Ground support systemsa71 Mission Operations and Ground Support Systems.a71 Integration and Testinga71 Systems Engineering and Analysis.Planning of requirements verification pro

20、cessesa71 Systems Engineering and Analysis.Engineering design and project processes and standardsa71 Program Management.a71 Safety and Mission Assurance.Qualitya71 Safety and Mission Assurance.Reliabilitya71 Additional Categories.a71 Additional Categories.Communication Systemsa71 Safety and Mission

21、Assurance.Product AssuranceAdditional Info: a71 Project: Hinode / Solar-BProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Lessons Learned Entry: 2157Approval Info: a71 Approval Date: 2010-04-29a71 Approval Name: mbella71 Approval Organization: HQProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-