David C. Leader Vice President HydroLynx Systems, Inc. 8/8/2018 7:39 AM Tips and tricks to simplify your flood warning system upgrade to the ALERT2 protocol David C. Leader Vice President HydroLynx Systems, Inc. © 2007 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries. The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

ALERT2 Advantages Data rate increase from 300 to 4800 baud Data error detection and correction Data collision avoidance using TDMA Data resolution increase from 0-2047 Data calibration in engineering units Data time stamp at transmitter using GPS Data repeat controlled by hop limit Data packet counter for lost packet detection Station ID range expanded Test mode sets flag for test data transmit

ALERT2 Backbone Advantages ALERT data repeat to other agencies longer needed. Large unmanageable ALERT1 radio network divided into smaller ALERT2 networks ALERT2 networks have separate frequencies No longer troubled by other agency malfunctioning transmitters that are on different frequencies. Coordinate TDMA and repeater use with local agencies sharing frequency Exchange data through internet Export SHEF data to NWS Import SHEF data from other ALERT users

ALERT2 Migration Plan ALERT2 radio frequency selection Use same frequency as ALERT1 Submit FCC application for new frequency ALERT2 source addresses Choose site ID (source address) range Assign individual station source address ALERT2 TDMA plan Determine station frame length Assign station TDMA slot assignments ALERT2 system registration Register ALERT2 station information with SAMS or local agency

ALERT2 Radio Frequency Radio frequency Best to use a new radio frequency for ALERT2 Many new frequencies are available at .0125 Mhz spacing Repeaters can receive ALERT1 on old frequency Transmit ALERT1 on old frequency Transmit ALERT2 on new frequency Mixing ALERT1 and ALERT2 on the same frequency will result in data collisions ALERT1 data loss and errors ALERT2 data loss but errors are rejected

ALERT2 Source Address Station ID numbers (source address) 10/16/2014 ALERT2 Source Address Station ID numbers (source address) Station ID number must be regionally unique Sensor ID numbers now range from 0 – 254 Data collection software will translate new station ID to store data report in database Coordinate ALERT2 station IDs regionally Most agencies start with station IDs above 10000 and with 1000 spacing between agencies Station ID ranges may be assigned by agency Register station ID in NHWC ALERT2 SAMS

ALERT2 TDMA Plan TDMA frame length TDMA slot length TDMA slot offset Minimum time between station transmissions A frame length of 1 minute allows each station to transmit data every minute if needed TDMA slot length Number of milliseconds limit for a station transmit Most stations have 500 millisecond slot lengths Weather station may use 1000 millisecond slot lengths TDMA slot offset Start time for station transmit in milliseconds from start of frame A station with a 5000 millisecond slot offset transmits 5 seconds after start of minute for a one minute frame

ALERT2 TDMA Frame Length 10/16/2014 ALERT2 TDMA Frame Length All stations and repeaters on the same transmit frequency use the same TDMA plan One minute frame allows 120 stations with 500 milliseconds slot lengths. 4 repeater 5000 milliseconds slot lengths every 15 seconds and 80 station 500 milliseconds slot lengths. Two minute frame allows 240 stations with 500 milliseconds slot lengths. 8 repeater 5000 milliseconds slot lengths every 15 seconds and 160 station 500 milliseconds slot lengths. When planning frame length, leave room for system expansion

ALERT2 TDMA Slot Length Minimum slot length is 500 milliseconds 10/16/2014 ALERT2 TDMA Slot Length Minimum slot length is 500 milliseconds Most stations can transmit all sensor data within a 500 millisecond slot length Weather stations may need a longer 1000 millisecond slot length Repeaters use longer slot lengths

TDMA Slot Offset Assignment Tips 10/16/2014 TDMA Slot Offset Assignment Tips Start with repeater slots Position rain only stations near start of frame No delay for sensor samples Position water level and weather station slots after 30 seconds Allows time for SDI sample or sensor power on time Position repeater slots after stations repeated

TDMA drift when GPS time sync lost 10/16/2014 TDMA drift when GPS time sync lost ALERT2 encoder loses GPS lock GPS time sync state set to drift (2) Change to random transmit time within frame Collisions can occur with stations that have GPS lock Greatest chance of collision for timed reports ALERT2 transmitter can will hold off timed transmission by one frame to reduce chance of collision Rain gauge TBR reports do not use hold off

ALERT2 TDMA 1 Minute Frame ALERT2 transmitters only 1 Minute Frame Minimum slot length 500ms Maximum slot length 1000ms 120 500ms slots available No repeater slots assigned 10/16/2014

ALERT2 TDMA 1 Minute Mixed ALERT2 transmitter and repeater slots 1 Minute Frame Repeater slot length 5000ms Station slot length 500 or 1000ms 4 Repeater slots 80 Station slots 20 Stations repeated per repeater slot < 5 seconds 10/16/2014

ALERT2 Upgrade Plan Update base station software to receive ALERT2 Test software with ALERT2 receiver benchmark data Replace ALERT1 receiver decoder with combined ALERT1/ALERT2 receiver decoder. Serial and network connection available Replace ALERT1 repeater with ALERT2 repeater ALERT1 transmitters repeated as ALERT2 Upgrade remote transmitters to ALERT2 Remote transmitter data repeated and received as ALERT2 Exchange ALERT2 data through internet Export and import SHEF data from other agencies

Upgrade ALERT1 receiver to ALERT2 Replace ALERT1 receiver with 5052RD-K ALERT2 receiver/decoder Add ALERT1 receiver/decoder option to collect legacy ALERT1 date during upgrade transition Rack mount installation recommended Desktop installation possible Use AC power adapter Connect to battery backup power system Stand alone battery with charger no longer used Antenna splitter uses same receiver antenna for ALERT1 and ALERT2

ALERT1 Receiver to be replaced

ALERT2 Receiver/Decoder with ALERT1 receive option

ALERT2 Receiver/Decoder/Repeater with ALERT2 transmit option

5052RD-K ALERT2 Receiver/Decoder ALERT1 and ALERT2 ALERT1 Transmitter AC Power Polyphaser ALERT1 Receiver Battery Backup Antenna Splitter Battery with charger ALERT2 Receiver Decoder ALERT1 Receiver Decoder

Antenna Splitter and Filters Install powered preamp after polyphaser Increases received signal to offset splitter and filter insertion losses Install antenna splitter after preamp Antenna splitters have small insertion loss Install cavity or crystal filters after splitter Separate filters required for ALERT1 and ALERT2 receiver frequencies Crystal filters have the best performance as filters Very compact size and inline installation 7dB insertion loss requires preamp for signal boost 8 week delivery so order in advance

ALERT2 Receiver Splitter and Filters Receiver Antenna ALERT1 Receive ALERT2 Receive Splitter PreAmp AC Power Supply

Antenna Splitter and Filters ALERT1 ALERT1 and ALERT2 ALERT1 Transmitter AC Power Polyphaser ALERT1 Receiver Battery Backup Antenna Splitter Battery with charger Crystal Filter Crystal Filter ALERT2 Receiver Decoder ALERT1 Receiver Decoder

Program ALERT2 Receiver/Decoder Set network IP address, netmask, gateway Set private time server if no internet connection Set client IP addresses to forward data packets Change login password Change SSH port

Make receiver network connections Connect network cables to ALERT1 and ALERT2 network ports ALERT2 receiver time sync through network Base station computers can make IP connections to receiver for data collection Network connection types Listen on TCP port for connections from multiple base station servers Port 4200 to stream ALERT2 ASCII Port 4201 to stream ALERT2 Binary Make a connection to a client base station server Define clients in /etc/default/alert2client

ALERT2 Receiver Network Output ALERT1 and ALERT2 ALERT1 Transmitter X ALERT Base Station Battery Backup Polyphaser ALERT1 Receiver ALERT1 Decoder Audio Serial AC Power Antenna Splitter Battery with charger Crystal Filter Crystal Filter ALERT2 Receiver Decoder ALERT1 Receiver Decoder Network

ALERT2 Receiver Network Output

Make receiver serial connections Connect serial cables to ALERT1 and ALERT2 serial ports Serial cable to portserver Base station computers can make IP connections to portserver for data collection Network connection required for ALERT2 receiver for time sync

ALERT2 Receiver Serial Output ALERT1 and ALERT2 ALERT1 Transmitter X ALERT Base Station Battery Backup Polyphaser ALERT1 Receiver ALERT1 Decoder Audio Serial AC Power Antenna Splitter Battery with charger Crystal Filter Crystal Filter ALERT2 Receiver Decoder ALERT1 Receiver Decoder Serial PortServer Network Serial Network time sync

Multiple Receiver Network Use multiple receivers instead of repeaters Eliminates radio traffic from receiver to base station Receive ALERT1 and ALERT2 Stream received data through network to base station Base station connects to multiple receivers

Multiple ALERT2 receivers ALERT1 Transmitter ALERT2 Transmitter ALERT2 ALERT1 Transmitter ALERT1 ALERT2 ALERT2 Transmitter Antenna Splitter ALERT2 Base Station ALERT1 Transmitter ALERT1 Crystal Filter Crystal Filter ALERT2 Receiver Decoder ALERT1 Receiver Decoder ALERT2 Network ALERT2 Transmitter Antenna Splitter Network Antenna Splitter Crystal Filter Crystal Filter ALERT2 Receiver Decoder ALERT1 Receiver Decoder Crystal Filter Crystal Filter ALERT2 Receiver Decoder ALERT1 Receiver Decoder Network Network

Lessons learned from installations Check type and gender of antenna cable connectors Polyphasers, splitters, crystal filters connect to N male cable connector ALERT2 receiver connects to a BNC male connector Connecting cable from polyphaser to splitter Check length of cable required Remove existing polyphaser from ALERT1 receiver? Preamp increase in signal level for ALERT1 may require a higher squelch level in radio receiver -104 dB instead of -113 dB

ALERT2 Rack Repeater with Rain Gauge Input

ALERT2 NEMA Repeater

ALERT2 CAN Repeater

ALERT2 Repeater Upgrade Phases Phase 1 converts ALERT1 repeaters into ALERT2 concentrators Receive ALERT1, transmit ALERT2 Single or dual antenna installations Dual antenna recommended Phase 2 converts ALERT2 concentrators into ALERT2 repeaters Receive ALERT1 and ALERT2, transmit ALERT2 Antenna splitter and filter use same receive antenna for ALERT1 and ALERT2 Recommendation: Skip Phase 1, deploy Phase 2

Phase 1 converts ALERT1 repeaters into ALERT2 concentrators ALERT1 Transmitter ALERT2 ALERT2 Base Station ALERT2 Transmitter ALERT1 Receive ALERT2 Transmit ALERT2 Concentrator ALERT1 Network ALERT2 Antenna Splitter ALERT1 ALERT1 Transmitter Crystal Filter Crystal Filter ALERT1 Transmitter ALERT1 Receive ALERT2 Transmit ALERT2 Receiver Decoder ALERT1 Receiver Decoder ALERT2 Concentrator Network

Phase 2 converts ALERT2 concentrators into ALERT2 repeaters ALERT1 Transmitter ALERT2 ALERT2 ALERT2 Receive ALERT2 Base Station ALERT2 Transmitter ALERT1 Receive ALERT2 Transmit ALERT2 Transmitter ALERT2 Repeater ALERT1 Network ALERT2 Antenna Splitter ALERT1 ALERT1 Transmitter Crystal Filter Crystal Filter ALERT1 Transmitter ALERT2 ALERT2 Receive ALERT1 Receive ALERT2 Transmit ALERT2 Receiver Decoder ALERT1 Receiver Decoder ALERT2 Repeater ALERT2 Transmitter Network

ALERT2 Repeater Splitter and Filters AC Power Receiver Antenna ALERT1 Receive ALERT2 Receive Splitter PreAmp AC Power Supply

ALERT2 Repeater Splitter and Filters Solar Power ALERT1 Receive Repeater Antenna ALERT2 Receive Splitter PreAmp Battery

ALERT2 Repeater Upgrade Single Antenna OLD: ALERT1 receive, ALERT1 transmit, 1 antenna, 1 radio ALERT1 Antenna ALERT1 Receive ALERT1 Modem 50386 Repeater ALERT1 RX/TX Radio ALERT1 Transmit Polyphaser UPGRADE: ALERT1, ALERT2 receive, ALERT1, ALERT2 transmit, 1 antenna, 2 radios ALERT1,2Antenna ALERT1 RX Radio ALERT1 Modem ALERT2 RX/TX Radio ALERT2 Demod ALERT2 Decoder 50386 Repeater Antenna Splitter Polyphaser ALERT1 Transmit GPS Antenna Polyphaser ALERT2 Transmit ALERT2 Encoder

ALERT2 Repeater Upgrade Dual Antenna OLD: ALERT1 receive, ALERT1 transmit, 2 antennas, 2 radios ALERT1 Receive Antenna ALERT1 RX Radio ALERT1 Modem 50386 Repeater Polyphaser ALERT1 Transmit Antenna ALERT1 TX Radio ALERT1 Transmit Polyphaser UPGRADE: ALERT1,2 receive with splitter, crystal filters, ALERT1, ALERT2 transmit, 2 antennas, 3 radios ALERT1,2 Receive Antenna Crystal Filter ALERT1 RX Radio ALERT1 Modem Antenna Splitter Polyphaser Crystal Filter ALERT2 RX Radio ALERT2 Demod ALERT2 Decoder 50386 Repeater ALERT2 Transmit Antenna Polyphaser ALERT1,2 TX Radio ALERT1 Transmit GPS Antenna Polyphaser ALERT2 Transmit ALERT2 Encoder

ALERT2 Repeater Desired Features ALERT2 repeater supports ALERT1 and ALERT2 receive pass/block User interface supports ALERT1 and ALERT2 pass/block list download through standard interface. ALERT2 repeater will not transmit past its TDMA slot length. Overflow packets are buffered then transmitted on the next frame (1 to 2 minutes); first in first out.

ALERT2 Transmitter Upgrades ALERT2 transmitter upgrade kits include: ALERT2 encoder PCB Mounting hardware Power harness and programming cable GPS antenna Mounting bracket, polyphaser, cables, strain relief, ties SMA antenna bulkhead connector and internal harness Maxon radio hardware ALERT2 radio harness and Firmware update

ALERT2 Transmitter Site Upgrade Recommendations Solar Panels Rain and level stations 5 Watt solar panel Weather or wireless link stations 10 Watt solar panel Battery New 22 Amp-hr gel cell battery

ALERT2 Transmitter New Features 10/16/2014 ALERT2 Transmitter New Features ALERT2 station ID is unique Sensor IDs are from 0 to 254. ALERT2 report types GSR, TBR, MSR, MMR, Concentrator ALERT2 sensor calibration Transmit finished and data with decimal point Trim analog data values outside of range Transmitter time sync with ALERT2 GPS Transmit GPS time status as sensor data Test mode transmit ALERT2 test flag Base station software flags test data Timed transmit holdoff on GPS time drift Holdoff timed transmit for one frame length

ALERT2 Sensor ID ALERT2 station ID is unique Sensor ID ranges Sensor IDs are from 0 to 254 ALERT2 uses the station ID and sensor ID together to identify a sensor data value Sensor ID ranges 0 to 8 are pre-defined 9 and 10 are defined by HydroLynx transmitters 11 to 254 can be used in your system as needed 255 is reserved for time stamp ID Sensor Rain gauge 1 Air temperature 2 Relative humidity 3 Barometric pressure 4 Wind speed 5 Wind direction 6 Wind peak 7 Water level 8 Battery 9 Digital status 10 GPS sync state 05/06/2014

ALERT2 General Sensor Report GSR Common report type supports all sensors, data type, decimal precision Sensor ID range: 0 – 254 Data types: Unsigned integer Signed integer Floating point Decimal precision set by transmitter 05/06/2014

ALERT2 Tipping Bucket Report TBR 05/06/2014 ALERT2 Tipping Bucket Report TBR The tipping bucket report compresses several rain gauge tip reports into one packet. Sensor ID is usually 0 Timing of rain gauge tips stored to nearest second. Base station software will file each rain gauge tip at the time it occurred. Data receive delays due to TDMA do not effect rainfall data analysis. Recommend transmitter report use: General Sensor Report for rain gauge timed reports Tipping Bucket Report for rain gauge tip events

ALERT2 Multi-Sensor Report MSR MSR compresses sensor data in an efficient packet An MSR containing 8 sensor readings uses 12 bytes The equivalent GSR for eight sensors uses 36 bytes MSR limitations English units for sensors are pre-defined Wind speed and battery resolution are limited Water level range limit is -327.67 to +327.67 feet ID Sensor Bytes Format Resolution Units 1 Air temperature 2 Signed 0.1 deg F Relative humidity Unsigned % 3 Barometric pressure mb 4 Wind speed mph 5 Wind direction deg 6 Wind peak 7 Water level 0.01 ft 8 Battery V

ALERT2 Multi-Sensor Report MMR MMR compresses sensor data in an efficient packet An MMR containing 8 sensor readings uses 12 bytes The equivalent GSR for eight sensors uses 36 bytes MMR limitations Metric units for sensors are pre-defined Wind speed and battery resolution are limited Water level range limit is -327.67 to +327.67 feet ID Sensor Bytes Format Resolution Units 1 Air temperature 2 Signed 0.1 deg C Relative humidity Unsigned % 3 Barometric pressure mb 4 Wind speed kph 5 Wind direction deg 6 Wind peak 7 Water level 0.001 m 8 Battery V

ALERT2 Hop Limit Hop limit is number of times packet is repeated Hop limit is set at transmitter 0 = No repeat 1 – 6 = Repeat 1 to 6 times 7 = Unlimited repeats When a packet is repeated, the hop limit count is decremented (unless hop limit is 7) When count reaches 0, no more repeats Repeater hop limit Does not affect repeat of packets received Limits repeats of local sensor data Limits repeats of ALERT1 data concentrator packets

Questions?