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Version 10.3 by Sima Mousavi on 2024/01/29 16:33
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1 = **What is iDAS?** =
2
3 **iDAS** stands for **Integrated Distributed Acoustic Sensing**. This advanced system utilizes the principle of Rayleigh backscattering in optical fibers to measure strain rates along the fiber's length. It's a cutting-edge technology predominantly used in fields like geophysics, where it's crucial for monitoring seismic activities, as well as in industrial applications like pipeline monitoring and security systems.
4
5 === **Safety first!** ===
6
7 === ===
8
9 (% class="box warningmessage" %)
10 The iDAS uses a Class 1 laser, which is generally considered safe for most applications. However, direct exposure to the eye should be avoided to prevent any risk of eye injury.
11 \\Cables and fibers may create tripping hazards. Ensure that the routing of cables is done in a way that minimizes the risk of accidents.
12
13 ----
14
15 === **System Components** ===
16
17
18 The iDAS system consists of the following components:
19
20 1. **Interrogator unit:** This unit houses the laser, detector, and electronics for processing the backscattered light signal. It records various settings such as the optical system configurations, spatial sampling rates, and the duration of data acquisition. 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.
21 1. **Optical fiber:** The optical fiber is the sensor that is used to measure strain rate.
22 1. **Data acquisition software**: This software is used to control the interrogator unit and to acquire and process the data. It records various settings such as the optical system configurations, spatial sampling rates, and the duration of data acquisition.
23
24 ----
25
26 = **DAS Data Collection System** =
27
28 ==== **1. Surface Installation** ====
29
30 * **Cable Arrangement:** The optical fiber cable can be a single long continuous cable or multiple cables with connectors, used across different installation environments.
31 * **Cable Types:** Cables may vary in construction types based on the installation environment.
32 * **Geographical Metadata:** Parameters related to geographical location are specified for easy searchability in databases.
33
34 ==== **2. Installation Environments** ====
35
36 * **Shallow Burial:** The cable can be shallowly buried.
37 * **In-Conduit Installation:** The cable can also be installed within a conduit.
38 * **Water Installation:** Suitable for underwater environments.
39
40 ==== **3. Channels** ====
41
42 * **Sensor Distribution:** Channels represent sensors distributed along the fiber array at fixed intervals.
43 * **Physical Location Determination:** The physical locations of these channels are ascertainable through methods like tap tests and GPS tracking.
44 * **Metadata for Channels:** Each channel or group of channels has its own metadata block, detailing specifics like location and properties.
45
46 [[image:1706489800616-982.png]]
47
48
49
50 [[image:1706488566274-805.png]]
51
52 ----
53
54 = **DAS Metadata Schema** =
55
56 ==== **1. Interrogator** ====
57
58 * **Required:** Interrogator ID, manufacturer, model.
59 * **Optional:** Serial number, firmware version.
60
61 ==== **2. Acquisition Parameters** ====
62
63 * **Required:** Interrogator ID, acquisition ID, unit of measure, acquisition start and end time, acquisition sample rate, gauge length, number of channels, spatial sampling interval.
64 * **Optional:** Pulse rate, pulse width.
65
66 ==== **3. Overview** ====
67
68 * **Required:** Network code, location, start date, end date, point of contact.
69 * **Optional:** Digital Object Identifier (DOI), purpose of data collection, funding agency.
70
71 ==== **4. Cable Information** ====
72
73 * **Required:** Cable ID, cable bounding box.
74 * **Optional:** Cable owner, cable installation date, cable characteristics.
75
76 ==== **5. Fiber Information ('Native format')** ====
77
78 * **Required:** Cable ID, fiber ID, fiber geometry, fiber mode, fiber refraction index.
79 * **Optional:** Fiber optical length, fiber start and end location, fiber one-way attenuation, fiber winding angle.
80
81 ==== **6. Channel Group** ====
82
83 * **Required:** Interrogator ID, acquisition ID, channel group ID, cable ID, fiber ID, coordinate generation date.
84 * **Optional:** Location method, coordinate reference frame, first/last usable channel ID, uncertainty of various coordinates (x, y, latitude, longitude, elevation, depth, strike, dip).
85
86 ==== **7. Channel** ====
87
88 * **Required:** Channel group ID, channel ID, coordinates (x, y, latitude, longitude).
89 * **Optional:** Elevation above sea level, depth below surface, distance along fiber, strike, dip.
90
91 ----
92
93 === ===
94
95 = **Pre-processing Steps for DAS Data (2.5 months, 90 TB)** =
96
97 1. (((
98 **Create a Deployment Log**
99
100 * Document key details like photonics settings, duration of data collection, instances of hard disk failure, power outages, etc.
101 )))
102 1. (((
103 **Generate Geographic Coordinates**
104
105 * Assign latitude and longitude coordinates to each DAS channel for spatial referencing.
106 )))
107 1. (((
108 **Data Conversion**
109
110 * Convert the raw DAS time series data from counts to strain rate, which is more meaningful for seismic analysis.
111 )))
112 1. (((
113 **Data Decimation**
114
115 * 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.
116 )))
117 1. (((
118 **Extract Specific Time Series**
119
120 * Isolate time series data of special interest, such as those related to earthquake events, for detailed analysis.
121 )))
122 1. (((
123 **Data Hosting**
124
125 * Store the processed data on Research School of Earth Sciences (RSES) clusters and the National Computational Infrastructure (NCI) for accessibility and further analysis.
126 )))
127 1. (((
128 **Extract Data and Instrument Response from Seismic Nodes**
129
130 * Retrieve both the raw data and the corresponding instrument response characteristics for accurate interpretation of the seismic signals.
131 )))
132 1. (((
133 **Long-term Archiving and Data Sharing**
134
135 * 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.
136 )))
137 1. (((
138 **Data Access and Record Keeping**
139
140 * 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.
141 )))
142
143 === ===
144
145 ----
146
147 == **iDAS Software Overview** ==
148
149 ==== **Operating System Compatibility:** ====
150
151 * (((
152 The iDAS system software is designed to run on the Windows operating system, with the current version compatible with Windows 7.
153 )))
154
155 ==== **Accessing the System:** ====
156
157 * (((
158 **User Login:** The system is set up to log in automatically as "User", without requiring any credentials.
159 )))
160 * **Software Shortcut:** A shortcut to access the iDAS software is conveniently placed on the desktop for easy access.
161
162 ==== **Data Acquisition Controls** ====
163
164 * (((
165 **Start / Stop:** Easily control the start and stop of data acquisition using the current settings.
166 )))
167 * **Calibrate Reference:** Recalibrate reference levels as needed.
168 * **Exit:** Safely exit the iDAS software.
169
170 ==== **Configuration iDAS Setup Wizard:** ====
171
172 (% class="wikigeneratedid" %)
173 Provides a guided, step-by-step process for setting up the iDAS system.
174
175 * (((
176 **iDAS Configuration:** Access the iDAS configuration window for advanced settings.
177 )))
178 * **Trigger Mode:** Opens the trigger configuration window for specific acquisition needs.
179
180 ==== **Operating Modes ** ====
181
182 * (((
183 **Available Modes:** Acoustic, Waterfall, Stacking, Security, and OTDR.
184 )))
185 * **Functionality:** Each mode presents the acoustic data from iDAS in unique formats.
186 * **Detailed Information:** See pages 19-23 of the Standard iDAS manual for comprehensive details on each mode.
187
188 === ===
189
190 === [[image:1706506304897-924.png]] ===
191
192 ----
193
194 = **Silixa iDAS Setup Manual for Reoccupying/Duplicating Experiment** =
195
196 = **General Information** =
197
198 * **Experiment Name:** ~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~__
199 * **Local Date:** ~_~_~_~_/~_~__**/202**
200 * **Local Time:** ~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~__
201 * **Personnel:** ~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_
202 * **Site Condition Notes:**
203 ** [Space for detailed notes about the site condition, any upkeep performed, and changes made since the last visit.]
204
205 ----
206
207 ==== **Setup Procedure** ====
208
209 1. (((
210 **Open iDAS Box**
211
212 * Serial Number: ~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~__
213 * IP Address: ~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_
214 )))
215 1. (((
216 **Check Laser Lock**
217
218 * Ensure the lever on the LASER/RIGHT side of the iDAS is in the locked position (LEVER UP).
219 )))
220 1. (((
221 **Placement of iDAS**
222
223 * Position the iDAS on a stable surface.
224 * Ensure clear air flow around the fan vents.
225 )))
226 1. (((
227 **UPS Setup** (If applicable)
228
229 * Connect the UPS to a power source.
230 * Plug the NAS into the UPS using the special cable with a rectangular connector.
231 * Connect the monitor to the UPS.
232 )))
233 1. (((
234 **Peripheral Connections**
235
236 * Connect a computer monitor, mouse, and keyboard to the iDAS.
237 )))
238 1. (((
239 **GPS Antenna Connection**
240
241 * Connect the GPS antenna to the left-side socket on the front of the iDAS using a special adapter.
242 )))
243 1. (((
244 **Fibre Optic Connection**
245
246 * Clean both the fibre optic cable and the socket with a 1-click cleaner before connection.
247 * Use the guide/tip for cleaning the fibre and clean the socket without it.
248 )))
249 1. (((
250 **Powering the iDAS**
251
252 * Connect the iDAS to a power socket or UPS.
253 * Note: The iDAS turns on automatically when connected to power. Use the power button at the bottom left if it does not.
254 )))
255 1. (((
256 **Network Drive Mapping**
257
258 * Open File Explorer and select 'This PC' from the left pane.
259 * On the File Explorer ribbon, select 'More' > 'Map network drive'.
260 * Choose a drive letter from the 'Drive' list.
261 )))
262 1. (((
263 **Open iDAS Software**
264
265 * Use the link/shortcut on the Desktop.
266 )))
267 1. (((
268 **GPS Satellite Confirmation**
269
270 * Check for a green light in the top row of the software interface indicating GPS satellite detection.
271 )))
272 1. (((
273 **Lever/Interlock Adjustment**
274
275 * Lower the lever/interlock (as mentioned in step 2) before starting data acquisition.
276 )))
277 1. (((
278 **Configuration File Duplication**
279
280 * Use 'current.cfg' for duplicating previous setup.
281 * The file is located at C:/Silixa/Data/current.cfg.
282 * Copy this file to the desktop and save it with a new filename.
283 )))
284 1. (((
285 **iDAS Configuration Settings**
286
287 * Navigate to the 'Configuration' tab and click 'iDAS configuration'.
288 * Check all values under 'system'.
289 * Under 'application', enable error messages.
290 * In 'saving', select 'acoustic saving', choose 'tdms', and set the file save location and identifier.
291 * Leave default parameters in 'measure'.
292 )))
293 1. (((
294 **Mode Selection**
295
296 * Toggle between Acoustic mode, Waterfall mode, and OTDR mode to check data recording.
297 )))
298 1. (((
299 **Photograph OTDR Mode**
300
301 * Document the OTDR mode settings with a photograph.
302 )))
303 1. (((
304 **Photograph Waterfall Mode**
305
306 * Similarly, take a picture of the Waterfall mode settings.
307 )))
308 1. (((
309 **Configuration File Saving**
310
311 * Save the configuration file in .cfg format in a separate location without overwriting the existing one.
312 )))
313 1. (((
314 **Software Check**
315
316 * Ensure QFinder, Teamviewer, and Microsoft Remote Desktop are installed.
317 )))
318 1. (((
319 **Remote Access Setup**
320
321 * Open Teamviewer or Microsoft Remote Desktop.
322 * For Teamviewer, photograph the ID and password and ensure it remains open.
323 * For Microsoft Remote Desktop, record the IP address and test remote access with a separate laptop.
324 )))
325 1. (((
326 **Final Mode Setting**
327
328 * Switch to OTDR mode for ongoing operation (avoids excessive memory usage of Waterfall mode).
329 )))
330
331 ----
332
333 ==== **Important Reminders** ====
334
335 * Always ensure that the iDAS is connected to a suitably earthed power socket or UPS for safety.
336 * Regularly check the condition of all cables and connectors.
337 * Before leaving the setup, confirm that data saving is active if required.
338 * Keep a log of all actions taken during the setup for future reference and troubleshooting.
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346 [[Caption>>image:1706488806394-168.png]]
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349 [[image:https://photos.fife.usercontent.google.com/pw/ABLVV86phmYsze0lp1yzL-gs6stE23rmgKbOxcpCRhFmK9s25zf5UHBkgbFcOg=w1440-h2556-s-no-gm?authuser=0]]
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352
353 [[How to clean the optical connector>>image:1706488909085-143.png||alt="How to clean the optical connector"]]
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