Global Report Cards

During the November 1996 Shanghai SLR Workshop, Mike Pearlman presented some guidelines for high performance SLR systems. The intent was to establish metrics so that system performance could be measured and regularly reported. The metrics were intended as a minimum performance goal. Issues of weather and other operating conditions will determine how easily a station can satisfy these goals. On the other hand, stations that do not provide a sufficient data yield will be of diminished value to the data users.

Performance guidelines, which continue to evolve as our service matures, are divided into three categories (data quantity, data quality, and operational compliance).

Yearly data quantity guidelines are:

1000 Low Earth Satellite (LEO) Passes
400 LAGEOS 1,2 Passes
100 High Satellite Passes

Data quality guidelines are:

1 cm LAGEOS NP precision
2 cm short term bias stability (1)
1 cm long term bias stability (2)

Operational compliance guidelines are:

Data delivery within 12 hours (data latency)
Specified ILRS NP data format
Current site and system information form (i.e. site log)

(1) the standard deviation about the mean of the pass-by-pass range biases on from the CSR Weekly LAGEOS analysis.

(2) the standard deviation of the monthly range bias estimates from the CSR Weekly LAGEOS analysis for at least 8 of the last 12 months.

Responsible Government Official: Carey Noll
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