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National Flood Workshop Houston, Texas October 2010. ALERT2 Protocol Performance. Don Van Wie, Telos Services R. Chris Roark, Blue Water Design, LLC. ALERT2 Concentration Protocol is in production in Overland Park/KCMO for repeater-to-base path
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National Flood Workshop Houston, Texas October 2010 ALERT2 Protocol Performance Don Van Wie, Telos Services R. Chris Roark, Blue Water Design, LLC
ALERT2 Concentration Protocol is in production in Overland Park/KCMO for repeater-to-base path ALERT2 is operating in parallel with ALERT on repeater-to-base leg in Urban Drainage and Flood Control District ALERT2 Implementations
UDFCD: ALERT v ALERT2 side-by-side comparisons • 8 months, 2 million ALERT messages analyzed • Overland Park: Logging at repeater sites permits exact determination of ALERT2 losses • Early June storms with partial logging • Full month analysis for September 2010 Studies
Demonstrate reliability of hardware in normal operating environment Quantify the relative performance of ALERT/ALERT2 Verify or and adjust the operating parameters based on operations at a production scale Purpose of testing
No hardware failures ALERT2 data loss “over the air” is typically less than 5 reports per 10,000 over any path that is suitable for ALERT Relative ALERT2 performance improves as traffic rates increase RF-only Preamble has been extended 55 msec Slot variance study shows 0.5 second slots are possible The Bottom Line
10 BWD Modulator/Encoders • 6.5 years of unit time accumulated • 4 BWD Demodulator/Decoders • 4.75 years of combined operation • About half of equipment is in unconditioned environment • NO Failures! HARdware performance
To eliminate false setting by anomalous readings: • Limit correction based on plausible drift rate • Lengthen time in lock before taking readings Coming improvements to gps synchronization algorithm
Lengthened preamble affects capacity • Affects first block only • Impact diluted as traffic increases • Size of required deadband controls available slot time; 100 msec will be adequate • 500 msec slots can be used for most gage sites • Capacity of 1 channel is 120 gages, 331 KBytes/ hour • 2 sec slot (repeater) can carry 630 Kbytes/hour or 157,500 ALERT Messages Implications for channel capacity
Ready for new ALERT Concentrator applications Low power repeater for 2011 Vendors are working on gage applications Implementation of Protocol Application layer What’s next…