Wiki source code of Distributed Acoustic Sensing (DAS)
Version 6.3 by Sima Mousavi on 2024/01/29 13:13
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6.3 | 1 | = **DAS Data Collection System** = |
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5.1 | 2 | |
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6.3 | 3 | ==== **1. Interrogator Unit** ==== |
| 4 | |||
| 5 | * **Function:** The interrogator unit is the core component of a DAS system. It sends laser pulses through the optical fiber and measures the backscattered light. | ||
| 6 | * **Recording Information:** It records various settings such as the optical system configurations, spatial sampling rates, and the duration of data acquisition. | ||
| 7 | * **Multiple Interrogators:** More than one interrogator may be used in an experiment. Each unit should have a unique identifier and is described in its respective metadata block. | ||
| 8 | |||
| 9 | ==== **2. Surface Installation** ==== | ||
| 10 | |||
| 11 | * **Cable Arrangement:** The optical fiber cable can be a single long continuous cable or multiple cables with connectors, used across different installation environments. | ||
| 12 | * **Cable Types:** Cables may vary in construction types based on the installation environment. | ||
| 13 | * **Geographical Metadata:** Parameters related to geographical location are specified for easy searchability in databases. | ||
| 14 | |||
| 15 | ==== **3. Fiber Optic Cable** ==== | ||
| 16 | |||
| 17 | * **Cable Composition:** Several optical fibers may be enclosed within one cable. | ||
| 18 | * **Metadata Identification:** The metadata identifies each individual fiber used in the acquisition, including its intrinsic properties. | ||
| 19 | |||
| 20 | ==== **4. Installation Environments** ==== | ||
| 21 | |||
| 22 | * **Shallow Burial:** The cable can be shallowly buried. | ||
| 23 | * **In-Conduit Installation:** The cable can also be installed within a conduit. | ||
| 24 | * **Water Installation:** Suitable for underwater environments. | ||
| 25 | |||
| 26 | ==== **5. Channels** ==== | ||
| 27 | |||
| 28 | * **Sensor Distribution:** Channels represent sensors distributed along the fiber array at fixed intervals. | ||
| 29 | * **Physical Location Determination:** The physical locations of these channels are ascertainable through methods like tap tests and GPS tracking. | ||
| 30 | * **Metadata for Channels:** Each channel or group of channels has its own metadata block, detailing specifics like location and properties. | ||
| 31 | |||
| 32 | === === | ||
| 33 | |||
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5.1 | 34 | ---- |
| 35 | |||
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6.3 | 36 | === === |
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5.1 | 37 | |
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6.3 | 38 | = **Pre-processing Steps for DAS Data (2.5 months, 90 TB)** = |
| 39 | |||
| 40 | 1. ((( | ||
| 41 | **Create a Deployment Log** | ||
| 42 | |||
| 43 | * Document key details like photonics settings, duration of data collection, instances of hard disk failure, power outages, etc. | ||
| 44 | ))) | ||
| 45 | 1. ((( | ||
| 46 | **Generate Geographic Coordinates** | ||
| 47 | |||
| 48 | * Assign latitude and longitude coordinates to each DAS channel for spatial referencing. | ||
| 49 | ))) | ||
| 50 | 1. ((( | ||
| 51 | **Data Conversion** | ||
| 52 | |||
| 53 | * Convert the raw DAS time series data from counts to strain rate, which is more meaningful for seismic analysis. | ||
| 54 | ))) | ||
| 55 | 1. ((( | ||
| 56 | **Data Decimation** | ||
| 57 | |||
| 58 | * Reduce the sampling rate from 1000 Hz to 100 Hz. This step is essential to manage data volume and focus on frequencies of interest for seismic activities. | ||
| 59 | ))) | ||
| 60 | 1. ((( | ||
| 61 | **Extract Specific Time Series** | ||
| 62 | |||
| 63 | * Isolate time series data of special interest, such as those related to earthquake events, for detailed analysis. | ||
| 64 | ))) | ||
| 65 | 1. ((( | ||
| 66 | **Data Hosting** | ||
| 67 | |||
| 68 | * Store the processed data on Research School of Earth Sciences (RSES) clusters and the National Computational Infrastructure (NCI) for accessibility and further analysis. | ||
| 69 | ))) | ||
| 70 | 1. ((( | ||
| 71 | **Extract Data and Instrument Response from Seismic Nodes** | ||
| 72 | |||
| 73 | * Retrieve both the raw data and the corresponding instrument response characteristics for accurate interpretation of the seismic signals. | ||
| 74 | ))) | ||
| 75 | 1. ((( | ||
| 76 | **Long-term Archiving and Data Sharing** | ||
| 77 | |||
| 78 | * Ensure that the data is archived in a format and location that supports long-term preservation and accessibility, such as the AuScope Distributed Acoustic Sensing (DAS) Collection. | ||
| 79 | ))) | ||
| 80 | 1. ((( | ||
| 81 | **Data Access and Record Keeping** | ||
| 82 | |||
| 83 | * Maintain records and access paths (e.g., NCI local file path) for the data, including metadata and other associated records, to facilitate future research and data sharing. | ||
| 84 | ))) | ||
| 85 | |||
| 86 | === === | ||
| 87 | |||
| 88 | === === | ||
| 89 | |||
| 90 | === === | ||
| 91 | |||
| 92 | === === | ||
| 93 | |||
| 94 | === === | ||
| 95 | |||
| 96 | ---- | ||
| 97 | |||
| 98 | = **Silixa iDAS Setup Manual for Reoccupying/Duplicating Experiment** = | ||
| 99 | |||
| 100 | = **General Information** = | ||
| 101 | |||
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5.1 | 102 | * **Experiment Name:** ~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~__ |
| 103 | * **Local Date:** ~_~_~_~_/~_~__**/202** | ||
| 104 | * **Local Time:** ~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~__ | ||
| 105 | * **Personnel:** ~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_ | ||
| 106 | * **Site Condition Notes:** | ||
| 107 | ** [Space for detailed notes about the site condition, any upkeep performed, and changes made since the last visit.] | ||
| 108 | |||
| 109 | ---- | ||
| 110 | |||
| 111 | ==== **Setup Procedure** ==== | ||
| 112 | |||
| 113 | 1. ((( | ||
| 114 | **Open iDAS Box** | ||
| 115 | |||
| 116 | * Serial Number: ~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~__ | ||
| 117 | * IP Address: ~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_ | ||
| 118 | ))) | ||
| 119 | 1. ((( | ||
| 120 | **Check Laser Lock** | ||
| 121 | |||
| 122 | * Ensure the lever on the LASER/RIGHT side of the iDAS is in the locked position (LEVER UP). | ||
| 123 | ))) | ||
| 124 | 1. ((( | ||
| 125 | **Placement of iDAS** | ||
| 126 | |||
| 127 | * Position the iDAS on a stable surface. | ||
| 128 | * Ensure clear air flow around the fan vents. | ||
| 129 | ))) | ||
| 130 | 1. ((( | ||
| 131 | **UPS Setup** (If applicable) | ||
| 132 | |||
| 133 | * Connect the UPS to a power source. | ||
| 134 | * Plug the NAS into the UPS using the special cable with a rectangular connector. | ||
| 135 | * Connect the monitor to the UPS. | ||
| 136 | ))) | ||
| 137 | 1. ((( | ||
| 138 | **Peripheral Connections** | ||
| 139 | |||
| 140 | * Connect a computer monitor, mouse, and keyboard to the iDAS. | ||
| 141 | ))) | ||
| 142 | 1. ((( | ||
| 143 | **GPS Antenna Connection** | ||
| 144 | |||
| 145 | * Connect the GPS antenna to the left-side socket on the front of the iDAS using a special adapter. | ||
| 146 | ))) | ||
| 147 | 1. ((( | ||
| 148 | **Fibre Optic Connection** | ||
| 149 | |||
| 150 | * Clean both the fibre optic cable and the socket with a 1-click cleaner before connection. | ||
| 151 | * Use the guide/tip for cleaning the fibre and clean the socket without it. | ||
| 152 | ))) | ||
| 153 | 1. ((( | ||
| 154 | **Powering the iDAS** | ||
| 155 | |||
| 156 | * Connect the iDAS to a power socket or UPS. | ||
| 157 | * Note: The iDAS turns on automatically when connected to power. Use the power button at the bottom left if it does not. | ||
| 158 | ))) | ||
| 159 | 1. ((( | ||
| 160 | **Network Drive Mapping** | ||
| 161 | |||
| 162 | * Open File Explorer and select 'This PC' from the left pane. | ||
| 163 | * On the File Explorer ribbon, select 'More' > 'Map network drive'. | ||
| 164 | * Choose a drive letter from the 'Drive' list. | ||
| 165 | ))) | ||
| 166 | 1. ((( | ||
| 167 | **Open iDAS Software** | ||
| 168 | |||
| 169 | * Use the link/shortcut on the Desktop. | ||
| 170 | ))) | ||
| 171 | 1. ((( | ||
| 172 | **GPS Satellite Confirmation** | ||
| 173 | |||
| 174 | * Check for a green light in the top row of the software interface indicating GPS satellite detection. | ||
| 175 | ))) | ||
| 176 | 1. ((( | ||
| 177 | **Lever/Interlock Adjustment** | ||
| 178 | |||
| 179 | * Lower the lever/interlock (as mentioned in step 2) before starting data acquisition. | ||
| 180 | ))) | ||
| 181 | 1. ((( | ||
| 182 | **Configuration File Duplication** | ||
| 183 | |||
| 184 | * Use 'current.cfg' for duplicating previous setup. | ||
| 185 | * The file is located at C:/Silixa/Data/current.cfg. | ||
| 186 | * Copy this file to the desktop and save it with a new filename. | ||
| 187 | ))) | ||
| 188 | 1. ((( | ||
| 189 | **iDAS Configuration Settings** | ||
| 190 | |||
| 191 | * Navigate to the 'Configuration' tab and click 'iDAS configuration'. | ||
| 192 | * Check all values under 'system'. | ||
| 193 | * Under 'application', enable error messages. | ||
| 194 | * In 'saving', select 'acoustic saving', choose 'tdms', and set the file save location and identifier. | ||
| 195 | * Leave default parameters in 'measure'. | ||
| 196 | ))) | ||
| 197 | 1. ((( | ||
| 198 | **Mode Selection** | ||
| 199 | |||
| 200 | * Toggle between Acoustic mode, Waterfall mode, and OTDR mode to check data recording. | ||
| 201 | ))) | ||
| 202 | 1. ((( | ||
| 203 | **Photograph OTDR Mode** | ||
| 204 | |||
| 205 | * Document the OTDR mode settings with a photograph. | ||
| 206 | ))) | ||
| 207 | 1. ((( | ||
| 208 | **Photograph Waterfall Mode** | ||
| 209 | |||
| 210 | * Similarly, take a picture of the Waterfall mode settings. | ||
| 211 | ))) | ||
| 212 | 1. ((( | ||
| 213 | **Configuration File Saving** | ||
| 214 | |||
| 215 | * Save the configuration file in .cfg format in a separate location without overwriting the existing one. | ||
| 216 | ))) | ||
| 217 | 1. ((( | ||
| 218 | **Software Check** | ||
| 219 | |||
| 220 | * Ensure QFinder, Teamviewer, and Microsoft Remote Desktop are installed. | ||
| 221 | ))) | ||
| 222 | 1. ((( | ||
| 223 | **Remote Access Setup** | ||
| 224 | |||
| 225 | * Open Teamviewer or Microsoft Remote Desktop. | ||
| 226 | * For Teamviewer, photograph the ID and password and ensure it remains open. | ||
| 227 | * For Microsoft Remote Desktop, record the IP address and test remote access with a separate laptop. | ||
| 228 | ))) | ||
| 229 | 1. ((( | ||
| 230 | **Final Mode Setting** | ||
| 231 | |||
| 232 | * Switch to OTDR mode for ongoing operation (avoids excessive memory usage of Waterfall mode). | ||
| 233 | ))) | ||
| 234 | |||
| 235 | ---- | ||
| 236 | |||
| 237 | ==== **Important Reminders** ==== | ||
| 238 | |||
| 239 | * Always ensure that the iDAS is connected to a suitably earthed power socket or UPS for safety. | ||
| 240 | * Regularly check the condition of all cables and connectors. | ||
| 241 | * Before leaving the setup, confirm that data saving is active if required. | ||
| 242 | * Keep a log of all actions taken during the setup for future reference and troubleshooting. | ||
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6.1 | 243 | |
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6.2 | 247 | [[image:1706489800616-982.png]] |
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6.1 | 248 | |
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6.2 | 249 | |
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6.1 | 251 | [[image:1706488566274-805.png]] |
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6.2 | 256 | [[Caption>>image:1706488806394-168.png]] |
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6.1 | 257 | |
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| 259 | [[image:https://photos.fife.usercontent.google.com/pw/ABLVV86phmYsze0lp1yzL-gs6stE23rmgKbOxcpCRhFmK9s25zf5UHBkgbFcOg=w1440-h2556-s-no-gm?authuser=0]] | ||
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6.2 | 263 | [[How to clean the optical connector>>image:1706488909085-143.png||alt="How to clean the optical connector"]] |
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6.3 | 280 |
