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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 === **Application Type Options** ===
190
191 1. **Diagnostic Setup Only:**
192 1*. Retrieves current settings for a basic diagnostic overview.
193 1. **Seismic Application:**
194 1*. Sets Data Output Frequency to 1000 Hz.
195 1*. Adjusts Data Output Spatial Resolution to 2 meters.
196 1. **Flow Monitoring:**
197 1*. Changes Data Output Frequency to 10,000 Hz.
198 1*. Sets Data Output Spatial Resolution to 0.25 meters.
199 1. **Security Monitoring:**
200 1*. Configures Data Output Frequency to 1000 Hz.
201 1*. Sets Data Output Spatial Resolution to 2 meters.
202
203 [[image:1706508500303-165.png]]
204
205
206 === **Detailed Parameter Information** ===
207
208 1. **Time Decimation and Output Decimation:**
209 1*. These values are calculated based on the physical fiber length.
210 1. **Measure Length (m):**
211 1*. Generated value: 10176 meters.
212 1*. Note: 'Measure Length' includes the reference fiber inside the iDAS unit, differentiating it from 'Physical Fibre Length'.
213 1. **Pulse Width (ns):**
214 1*. Generated value: 50 nanoseconds.
215 1*. Spatial Extent: A 50ns pulse corresponds to a 10m spatial extent.
216
217 [[image:1706508761205-307.png]]
218
219
220
221
222
223 === **Optimal Light Management** ===
224
225 * **Objective:** Achieve balanced light distribution across the region of interest in the iDAS system.
226
227 === **Adjustment Guidelines** ===
228
229 1. **Setting Optical Power:**
230 1*. Aim to have the start of the region of interest around or below +4000 units.
231 1*. Ensure the far end of the region of interest does not enter a non-linear response scheme.
232 1. **Consideration for Short Fibers:**
233 1*. In cases where the fiber length is short and non-linear effects are not observed, set the Optical Power to its maximum.
234 1*. **Power Scale:** The adjustment slider ranges from 0-100, representing the percentage of maximum power available.
235
236 === **Note on Optical Power Control** ===
237
238 * **Control Mechanism:** The slider provides a precise control mechanism to manage the intensity of light sent through the fiber.
239 * **Monitoring and Adjustment:** Continuously monitor and adjust as necessary to ensure optimal performance.
240
241 [[image:1706509177362-144.png]]
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243
244
245
246
247 XXXXXXXXXXX
248
249 [[image:1706509232964-660.png]]
250
251
252
253 == **Integrating GPS Antenna for Accurate Timing** ==
254
255 === **Installation and Connection Process** ===
256
257 **Connecting the GPS Antenna:**
258
259 * Connect one end of a coaxial cable with SMB female connectors to the GPS antenna.
260 * If you plan to mount the antenna, do so before connecting the cable.
261 * Connect the other end of the cable to the 'GPS Ant.' port located on the output panel at the front of the iDAS unit.
262
263 === **Monitoring GPS Status and Time** ===
264
265 * **GPS Information Display:** The GPS status and time are displayed on the Tool Bar of the iDAS software.
266 * **Status Indicators:**
267 ** **Red:** Antenna is not connected.
268 ** **Amber:** Antenna connected, but self-survey not completed.
269 ** **Green:** Antenna connected, self-survey completed, and timing is accurate.
270
271 [[image:1706509432197-316.png]]
272
273
274
275 **Primary Configuration Settings in iDAS**
276
277 These settings are integral to the operation of the iDAS system, significantly influencing aspects like the rate of data streaming. They encompass:
278
279 1. **Sampling Frequency:** Determines how often data is captured.
280 1. **Spatial Resolution:** Defines the level of detail in spatial data.
281 1. **Fiber Length:** Impacts the range over which data is collected.
282
283 In configuring these parameters, a balance must be struck. This involves aligning the system's physical capabilities, such as fiber length and spatial resolution, with the practical limits of data collection, including the volume of data generated. Adjusting these settings correctly is crucial for optimizing data quality while managing the data volume effectively. This balance ensures that the system meets the specific needs of each application without overwhelming storage or processing capabilities.
284
285
286 [[image:1706510182174-365.png]]
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289
290 [[image:1706510243501-784.png]]
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292
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294
295
296 === [[image:1706506304897-924.png]] ===
297
298 [[image:1706506500585-231.png]]
299
300 ----
301
302 = **Silixa iDAS Setup Manual for Reoccupying/Duplicating Experiment** =
303
304 = **General Information** =
305
306 * **Experiment Name:** ~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~__
307 * **Local Date:** ~_~_~_~_/~_~__**/202**
308 * **Local Time:** ~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~__
309 * **Personnel:** ~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_
310 * **Site Condition Notes:**
311 ** [Space for detailed notes about the site condition, any upkeep performed, and changes made since the last visit.]
312
313 ----
314
315 ==== **Setup Procedure** ====
316
317 1. (((
318 **Open iDAS Box**
319
320 * Serial Number: ~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~__
321 * IP Address: ~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_~_
322 )))
323 1. (((
324 **Check Laser Lock**
325
326 * Ensure the lever on the LASER/RIGHT side of the iDAS is in the locked position (LEVER UP).
327 )))
328 1. (((
329 **Placement of iDAS**
330
331 * Position the iDAS on a stable surface.
332 * Ensure clear air flow around the fan vents.
333 )))
334 1. (((
335 **UPS Setup** (If applicable)
336
337 * Connect the UPS to a power source.
338 * Plug the NAS into the UPS using the special cable with a rectangular connector.
339 * Connect the monitor to the UPS.
340 )))
341 1. (((
342 **Peripheral Connections**
343
344 * Connect a computer monitor, mouse, and keyboard to the iDAS.
345 )))
346 1. (((
347 **GPS Antenna Connection**
348
349 * Connect the GPS antenna to the left-side socket on the front of the iDAS using a special adapter.
350 )))
351 1. (((
352 **Fibre Optic Connection**
353
354 * Clean both the fibre optic cable and the socket with a 1-click cleaner before connection.
355 * Use the guide/tip for cleaning the fibre and clean the socket without it.
356 )))
357 1. (((
358 **Powering the iDAS**
359
360 * Connect the iDAS to a power socket or UPS.
361 * Note: The iDAS turns on automatically when connected to power. Use the power button at the bottom left if it does not.
362 )))
363 1. (((
364 **Network Drive Mapping**
365
366 * Open File Explorer and select 'This PC' from the left pane.
367 * On the File Explorer ribbon, select 'More' > 'Map network drive'.
368 * Choose a drive letter from the 'Drive' list.
369 )))
370 1. (((
371 **Open iDAS Software**
372
373 * Use the link/shortcut on the Desktop.
374 )))
375 1. (((
376 **GPS Satellite Confirmation**
377
378 * Check for a green light in the top row of the software interface indicating GPS satellite detection.
379 )))
380 1. (((
381 **Lever/Interlock Adjustment**
382
383 * Lower the lever/interlock (as mentioned in step 2) before starting data acquisition.
384 )))
385 1. (((
386 **Configuration File Duplication**
387
388 * Use 'current.cfg' for duplicating previous setup.
389 * The file is located at C:/Silixa/Data/current.cfg.
390 * Copy this file to the desktop and save it with a new filename.
391 )))
392 1. (((
393 **iDAS Configuration Settings**
394
395 * Navigate to the 'Configuration' tab and click 'iDAS configuration'.
396 * Check all values under 'system'.
397 * Under 'application', enable error messages.
398 * In 'saving', select 'acoustic saving', choose 'tdms', and set the file save location and identifier.
399 * Leave default parameters in 'measure'.
400 )))
401 1. (((
402 **Mode Selection**
403
404 * Toggle between Acoustic mode, Waterfall mode, and OTDR mode to check data recording.
405 )))
406 1. (((
407 **Photograph OTDR Mode**
408
409 * Document the OTDR mode settings with a photograph.
410 )))
411 1. (((
412 **Photograph Waterfall Mode**
413
414 * Similarly, take a picture of the Waterfall mode settings.
415 )))
416 1. (((
417 **Configuration File Saving**
418
419 * Save the configuration file in .cfg format in a separate location without overwriting the existing one.
420 )))
421 1. (((
422 **Software Check**
423
424 * Ensure QFinder, Teamviewer, and Microsoft Remote Desktop are installed.
425 )))
426 1. (((
427 **Remote Access Setup**
428
429 * Open Teamviewer or Microsoft Remote Desktop.
430 * For Teamviewer, photograph the ID and password and ensure it remains open.
431 * For Microsoft Remote Desktop, record the IP address and test remote access with a separate laptop.
432 )))
433 1. (((
434 **Final Mode Setting**
435
436 * Switch to OTDR mode for ongoing operation (avoids excessive memory usage of Waterfall mode).
437 )))
438
439 ----
440
441 ==== **Important Reminders** ====
442
443 * Always ensure that the iDAS is connected to a suitably earthed power socket or UPS for safety.
444 * Regularly check the condition of all cables and connectors.
445 * Before leaving the setup, confirm that data saving is active if required.
446 * Keep a log of all actions taken during the setup for future reference and troubleshooting.
447
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450
451 [[Caption>>image:1706488806394-168.png]]
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454 [[image:https://photos.fife.usercontent.google.com/pw/ABLVV86phmYsze0lp1yzL-gs6stE23rmgKbOxcpCRhFmK9s25zf5UHBkgbFcOg=w1440-h2556-s-no-gm?authuser=0]]
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457
458 [[How to clean the optical connector>>image:1706488909085-143.png||alt="How to clean the optical connector"]]
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