FAQ - Revision history

Admin at 13:34, 25 April 2018

2018-04-25T13:34:33Z

Msemm at 15:52, 28 February 2016

2016-02-28T15:52:04Z

Msemm at 13:53, 10 January 2016

2016-01-10T13:53:29Z

Msemm: /* GSM cell IDs with more than 16 bit */

2016-01-10T13:50:32Z

‎GSM cell IDs with more than 16 bit

Msemm: /* GSM cell IDs with more than 16 bit */

2016-01-10T13:44:49Z

‎GSM cell IDs with more than 16 bit

Msemm: /* GSM cell IDs with more than 16 bit */

2016-01-10T13:39:58Z

‎GSM cell IDs with more than 16 bit

Msemm: /* GSM cell IDs with more than 16 bit */

2016-01-10T13:39:02Z

‎GSM cell IDs with more than 16 bit

Msemm at 13:37, 10 January 2016

2016-01-10T13:37:48Z

Msemm at 13:36, 10 January 2016

2016-01-10T13:36:22Z

Msemm: /* Cell xxx is shown on the map but is not in cell_towers.csv file */

2015-09-09T15:52:28Z

‎Cell xxx is shown on the map but is not in cell_towers.csv file

@@ Line 1: / Line 1: @@
-[[File:OpenCellID banner FAQ.png|998px]]
+[[File:OpenCellID banner FAQ2.png|998px]]
 <br>
 <br>

@@ Line 178: / Line 178: @@
 This changed with version 4.3 (API 18) when separate class CellIdentityWcdma was added. It's possible that some manufacturers have not yet updated their phones correctly and such behavior will take place on newer Android versions as well.
 |}
 <br>
 <br>

@@ Line 21: / Line 21: @@
 Most of measurements from older export files (like measurements_1.csv) have measurements only for GSM and UMTS networks.<br>
 At the moment, only the few recent export files have the <radio> field, but we are working on improving exported files and to add the <radio> information to all measurements. It should be done together with the database cleanup in Q1 2015.<br>
-At the moment you can roughly assume that if a cell has a cell id > 65535 then the cell belongs to a UMTS network, otherwise to a GSM network.
+At the moment you can roughly assume that if a cell has a cell ID > 65535 then the cell belongs to a UMTS network, otherwise to a GSM network.
 ===Calculated cell position vs exact cell position===
@@ Line 28: / Line 28: @@
 You can find out whether any cell position is exact or not as follows: please read the data format description at http://wiki.opencellid.org/wiki/Menu_map_view#database.<br>The field "changeable" indicates whether the cell is averaged ("true" value) or exact ("false").
-Currently it is not possible to upload measurements with "changeable" flag set to "false". The reason for this is, that this upload would make all measurements of a cell id obsolete.
+Currently it is not possible to upload measurements with "changeable" flag set to "false". The reason for this is, that this upload would make all measurements of a cell ID obsolete.
 The OpenCellID admins have the possibility to upload such data. So if you have such data and if this data has a proper license then please send the data by e-mail to the OpenCellID team for uploading it to the OpenCellID database including some information how this data was compiled.
@@ Line 52: / Line 52: @@
 RSSI [dBm] >= -100: ASU = 1
-===Long CellID vs. short Cell ID===
+===Long cell ID vs. short cell ID===
 The formula for the long cell ID is as follows:<br>
 Long CID = 65536 * RNC + CID

@@ Line 166: / Line 166: @@
 ===GSM cell IDs with more than 16 bit===
-On some phones GSM cell IDs are reported with more than 16 bit (higher than 0XFFFF).<br>
+{|
 It has also been found that on the same phone in the same network the same cell ID has been reported with different network types.
@@ Line 174: / Line 176: @@
 # Cell ID type field on the screenshot below is probably based on class name from Android.<br>
 When API 17 was introduced to Android 4.2 there was no separate class for UMTS cells, instead they used same class as for GSM and added there PSC field (now deprecated). (see http://developer.android.com/reference/android/telephony/CellIdentityGsm.html#getPsc() ).<br>
-This changed with version 4.3 (API 18) when separate class CellIdentityWcdma was added. It's possible that some manufacturers have not yet updated their phones correctly and such behavior will take place on newer Android versions as well.<br>
+This changed with version 4.3 (API 18) when separate class CellIdentityWcdma was added. It's possible that some manufacturers have not yet updated their phones correctly and such behavior will take place on newer Android versions as well.
 <br>

@@ Line 174: / Line 174: @@
 # Cell ID type field on the screenshot below is probably based on class name from Android.<br>
 When API 17 was introduced to Android 4.2 there was no separate class for UMTS cells, instead they used same class as for GSM and added there PSC field (now deprecated). (see http://developer.android.com/reference/android/telephony/CellIdentityGsm.html#getPsc() ).<br>
-This changed with version 4.3 (API 18) when separate class CellIdentityWcdma was added. It's possible that some manufacturers have not yet updated their phones correctly and such behavior will take place on newer Android versions as well.
+This changed with version 4.3 (API 18) when separate class CellIdentityWcdma was added. It's possible that some manufacturers have not yet updated their phones correctly and such behavior will take place on newer Android versions as well.<br>

@@ Line 171: / Line 171: @@
 From technical point of view this seems to be incorrect as GSM defines 16 bit cell ID.<br>
 There are two possible explanations:<br>
-) We have seen many phones returning wrong network type or rest of values when switching between network technologies like GSM and UMTS. This seems to be a non-transactional operation on hardware / Android level.
+# We have seen many phones returning wrong network type or rest of values when switching between network technologies like GSM and UMTS. This seems to be a non-transactional operation on hardware / Android level.
+# Cell ID type field on the screenshot below is probably based on class name from Android.<br>
-) Cell ID type field on the screenshot below is probably based on class name from Android.<br>
 When API 17 was introduced to Android 4.2 there was no separate class for UMTS cells, instead they used same class as for GSM and added there PSC field (now deprecated). (see http://developer.android.com/reference/android/telephony/CellIdentityGsm.html#getPsc() ).<br>
 This changed with version 4.3 (API 18) when separate class CellIdentityWcdma was added. It's possible that some manufacturers have not yet updated their phones correctly and such behavior will take place on newer Android versions as well.

← Older revision		Revision as of 13:36, 10 January 2016
Line 164:		Line 164:
	If a cell is created then you can see it immediately on the map, but it will be available in cell_towers.csv next day only.<br>		If a cell is created then you can see it immediately on the map, but it will be available in cell_towers.csv next day only.<br>
	The cell_towers.csv file is newly created every night around 3pm UTC.		The cell_towers.csv file is newly created every night around 3pm UTC.
		+
		+	===GSM cell-ids with more than 16 bit===
		+	On some phones GSM cell IDs are reported with more than 16 bit (higher than 0XFFFF).
		+	It has also been found that on the same phone in the same network the same cellid has been reported with different network types.
		+
		+	From technical point of view this seems to be incorrect as GSM defines 16 bit cell ID.
		+	There are two possible explanations:
		+	1) W have seen many phones returning wrong network type or rest of values when switching between network technologies like GSM and UMTS. This seems to be a non-transactional operation on hardware / Android level.
		+
		+	2) Cell ID type field on the screenshot below is probably based on class name from Android.
		+	When API 17 was introduced to Android 4.2 there was no separate class for UMTS cells, instead they used same class as for GSM and added there PSC field (now deprecated). (see http://developer.android.com/reference/android/telephony/CellIdentityGsm.html#getPsc() )
		+	This changed with version 4.3 (API 18) when separate class CellIdentityWcdma was added. It's possible that some manufacturers have not yet updated their phones correctly and such behavior will take place on newer Android versions as well.

@@ Line 161: / Line 161: @@
 === Cell xxx is shown on the map but is not in cell_towers.csv file===
-This can happen, because cells are displayed on the map in real-time but cell_towers.csv file is generated on daily basis only.
+This can happen, because cells are displayed on the map in real-time but cell_towers.csv file is generated on daily basis only.<br>
-If a cell is created then you can see it immediately on the map, but it will be available in cell_towers.csv next day only.
+If a cell is created then you can see it immediately on the map, but it will be available in cell_towers.csv next day only.<br>
 The cell_towers.csv file is newly created every night around 3pm UTC.