IssueTracker

There appears to be an issue with ODM's implementation of Android 5G APIs, particularly on Samsung US/Canada/Japan/Korea devices using Qualcomm chipsets.

For these models:

• The 5G band (and other information) is missing except when the device has a standalone connection — This information should appear in cells from getAllCellInfo() when called with correct permissions.
• The device is able to surface this information — For example, the Samsung Service Mode application (com.sec.android.RilServiceModeApp) accessible via *#0011# does report the 5G band even when the array from getAllcellInfo is empty.
• With Android 11, Samsung devices with Exynos chipsets started reporting 5G cell information in NSA as well as standalone — This suggests a fix was targeted to these devices which had not been reporting such information previously. The problem remains with Qualcomm chipset models (and also some Exynos, e.g. 9820)

This behaviour has been observed on many device models, on both Android 10 and Android 11; for Samsung devices with Exynos chipsets this improved with Android 11.

Some affected devices: SM-G977B, SM-G977N, SM-G977U, SM-G977V, SM-G981U, SM-G981V, SM-G981N, SM-G9810, SM-G981W, SM-G986U, SM-G986U1, SM-G998U, SM-G998U1, SM-G998W, SM-G996W We can provide a more comprehensive list.

This bug effectively means one of the most important Android Telephony APIs is broken in several leading 5G markets (USA, Canada, Korea, Japan).

Specific examples

Reporting on standalone working OK in most cases

For T-Mobile USA, Qualcomm variant Samsung devices do not report 5G cells via getAllCellInfo, except when the connection is standalone when we do see 5G cells — or most often a single 5G cell. In other places using standalone 5G we, fairly reliably, see it being reported.

As an example, here is a JSON representation of getAllCellInfo seen in standalone on T-Mobile:

[{
  "registered": true,
  "connection_status": 0,
  "type": "nr",
  "nci": 4336029699,
  "nr_arfcn": 126490,
  "mcc": "310",
  "other_fields":"removed for brevity"
}]

Here the ARFCN is correctly reported, corresponding to ~630MHz. The fact that no LTE cells appear in the getAllCellInfo array shows it is standalone.

Standalone and NSA working OK on most Exynos Samsung devices

In other cases, such as this example from Vodafone Italy below (a Samsung device with an Exynos chipset), we see NR cells while the device is connected in NSA mode — note that the primary serving cell ("registered":true is LTE). Note also that the ARFCN is valid (although the NCI is not):

JSON representation of getAllCellInfo

[
  {
    "registered": true,
    "connection_status": 0,
    "type": "lte",
    "mcc": "222",
    "mnc": "10",
    "other_fields": "removed for brevity"
  },
  {
    "registered": false,
    "type": "lte",
    "other_fields": "removed for brevity"
  },
  {
    "registered": false,
    "connection_status": 0,
    "type": "nr",
    "nci": 9223372036854776000,
    "nr_arfcn": 645312,
    "mcc": "222",
    "mnc": "10",
    "other_fields": "removed for brevity"
  },
  {
    "registered": false,
    "connection_status": 0,
    "type": "nr",
    "nci": 9223372036854776000,
    "nr_arfcn": 645312,
    "other_fields": "removed for brevity"
  }
]

Reporting of ARFCN on NSA in getAllCellInfo not working on Qualcomm Samsung variants (e.g. USA, Korea, Japan, Canada)

In general, in NSA scenarios we do not see any NR cells appearing in getAllCellInfo for these devices.

Verizon is unique in that we do see NR cells in NSA mode on Samsung devices, but the ARFCN is always invalid, some of the signal strength information does appear valid:

JSON representation of getAllCellInfo

[
  {
    "registered": true,
    "connection_status": 0,
    "type": "lte",
    "mcc": "311",
    "mnc": "480",
    "dbm": -104,
     "other_fields": "removed for brevity"
  },
  {
    "registered": false,
    "type": "lte",
    "other_fields": "removed for brevity"
  },
  {
    "registered": false,
    "type": "lte",
    "other_fields": "removed for brevity"
  },
  {
    "registered": false,
    "type": "lte",
    "other_fields": "removed for brevity"
  },
  {
    "registered": false,
    "connection_status": 0,
    "type": "nr",
    "nci": 9223372036854776000,
    "nr_arfcn": 2147483647,
    "other_fields": "removed for brevity"
  }
]

Note that in ServiceMode band information is reported even when official APIs fail

Here is an image from Samsung Service Mode taken from an S10 in New York on 6th June 2021 showing band n41 and an NSA connection (LTE+NR):

https://drive.google.com/file/d/1NR0Uce722vgay-zCynA34_FD_VGs-uIg/view?usp=drive_web (NSA connection NYC T-Mobile S10.png)

Service Mode is working on many networks and in many locations.

This shows the chipset does provide information on the 5G band at a level accessible to apps (in this case com.sec.android.RilServiceModeApp) yet at the same moment in time as that image was taken, only LTE cells were appearing in getAllCellInfo.

Summary

The APIs Android offers are enable powerful means for understanding the user experience in various 5G scenarios. This information will be critical in tuning 5G rollouts and presneting consumers with meaningful information. However, on the most popular devices in several leading 5G markets these APIs are not reporting correctly.