We publish below a brief memorandum for a better understanding of the new advanced Wi-Fi parameters, introduced in Datalogic Android Devices and supported by the SDK 1.33 platform revisions
Wi-Fi Advanced Settings
1. Wi-Fi scan:
Scan interval and Scan interval max parameters control the Wi-Fi scan intervals when the device has the screen on and alternatively it is disconnected or it is connected to any Wi-Fi network.
The first scan is done when the device is woken up from a standby state, then the next scans are done in an exponential backoff fashion.
The second scan will be done after x seconds, then after 2 * x, then 4 * x… and so on, until it reaches the maximum value.
| Parameter | Unit | Min | Max | Default | |
|---|---|---|---|---|---|
| (Disconnected) | |||||
| Interval | sec | 2 | 300 | 5 | |
| Max Interval | sec | 2 | 300 | 10 | |
| (Connected) | |||||
| Interval | sec | 2 | 300 | 20 | |
| Max Interval | sec | 2 | 300 | 160 | |
2. Wi-Fi module:
The Wi-Fi Module menu contains the main settings for enabling the protocols, bands and channels used by the radio module, and for adjusting the Power Saving modes.
Parameters:
802.11 mode: controls the 802.11 mode the device will be using. The available values are “All enabled”, “802.11 a/b/g”, “802.11 b”, “802.11 b/g”, “802.11 a/b/g/n”.
(Default: All enabled).
Band selection: selects the band used by the device. The available values are 2.4GHz, 5 GHz.
(Default: All enabled).
Channels selection: controls the channels that will be enabled or disabled on the device. When a channel is disabled, the device won’t be able to communicate on that specific channel and thus won’t see any AP using that channel. The available ranges are 1-13, 36-64, 100-144, 149-173; selectable in any combination.
(Default: All enabled).
Power save: enables the power save mode and controls which kind of power save is used. The default value is power save enabled, if you notice a degradation in the VoIP call performance increase the value to Enabled for VoIP calls. The values available are as follows: Disabled / Enabled / Enabled for VoIP calls.
(Default: Enabled)
Verbose logging: enables/disables a more verbose Wi-Fi module logging.
Note: The Wi-Fi verbose information can be retrieved in the standard Android logcat file
(Default: Enabled)
3. Wi-Fi roaming
The Wi-Fi roaming menu contains useful parameters for fine tuning the radio module in managing roaming between Wi-Fi Access Points. For basic tuning, some predefined profiles can be used. For advanced tuning, the custom profile can be set and individual parameters can be adjusted.
This menu is NOT available on Memor 10.
Parameters:
Roaming profile: allows to select one of the four roaming presets. In a gradient from Slow to Aggressive, this settings influence the sensibility and the rapidity adopted by the device from hopping from an Access Point to the next one, rather than preferring to stay with the current AP when the signal degrades.
The available profiles are: “Slow”, “Standard”, “Aggressive”, “Custom”.
Default (Skorpio X5, Memor 20, JoyaTouch 22): Custom profile.
Roaming profiles preset configuration:
| (Sx5, M20, JT22) | (default) | ||||||
|---|---|---|---|---|---|---|---|
| Parameter | Unit | Min | Max | Slow | Std. | Aggr. | Custom |
| RSSI Threshold | db | 10 | 120 | 80 | 76 | 70 | 76 |
| RSSI Difference | db | 0 | 30 | 8 | 5 | 3 | 5 (*) |
(*) The default preset of RSSI Difference for Custom profile (default) on Memor 20 is 3 dB.
The pre-configured profiles and their respective names are the same on all devices (Slow, Standard, Aggressive, Custom), but the same profile may correspond to different values of a given parameter on different devices, because the values to be set for individual parameters on different models vary depending on the implemented radio module of the specific model.
In defining the various profiles, Datalogic has tried to minimize the differences between various models depending on the profile selected. However, given the complexity and variability of the environments in which Wi-Fi communications occur, some differences may be possible.
RSSI threshold: controls the signal threshold, expressed in dB, for triggering the roaming procedure. When the access point signal drops under the threshold, the device will begin scanning in background for suitable networks to roam to. The parameter is physically negative as in -76 dB, but written as positive.
(For Min, Max and default values see the tables above)
RSSI difference: controls the signal difference, expressed in dB, between the current access point the device is connected to and the target access point the device wants to roam to. If the target AP signal is higher than the current by at least the value of this parameter, the device will roam.
(For Min, Max and default values see the tables above)
Retry times (Memor 11 only): set the number of roaming retries before aborting the roaming procedure
(For Min, Max and default values see the tables above)
Recalculation interval (Memor 11 only): set the minimum time interval (in seconds) between roaming thresholds calculations.
(For Min, Max and default values see the tables above)
Beacon Period (Memor 11 only): set the interval (in seconds) between beacon listening
(For Min, Max and default values see the tables above)
Devices compatibility table
| Memor 10 Android 10 |
Memor 20 Android 11 |
Skorpio X5 Andorid 11 |
JoyaTouch 22 Android 11 |
|
|---|---|---|---|---|
| Wi-Fi Scan | ||||
| . Scan Interval (disc.) | x | x | x | x |
| . Scan Interval Max (disc.) | x | x | x | x |
| . Scan Interval (conn.) | x | x | x | x |
| . Scan Interval Max (conn.) | x | x | x | x |
| Wi-Fi module | ||||
| . 802.11 mode | x | x | x | |
| . Band Selection | x | x | x | |
| . Channels selection | x | x | x | |
| . Power Save | x | x | x | |
| . Verbose Logging | x | x | x | |
| Wi-Fi Roaming | x | x | x | |
| . Roaming Profile | x | x | x | |
| . RSSI Threshold | x | x | x | |
| . RSSI Difference | x | x | x | |