Transmissions (uplinks) of each node can use different transmission power, data rate and channels (frequencies). Depending on the ADR Mode this can either be manually defined by the administrator or automatically determined by the server.
Note this functionality must be also enabled in the device, which is indicated by the Use ADR flag.
This mode disables the ADR, regarless the Use ADR flag. The server will never attempt to modify the Power, Data Rates or Channels. Changes to the requested ADR parameters have no effect.
In this mode the server automatically adjusts the ADR parameters depending on the uplink signal quality.
The server calculates an average RSSI and SNR for the last 20 frames received.
- The Data Rate (Spreading Factor) is defined so that the LoRa demodulator SNR for the target Data Rate matches the observed average uplink SNR.
- When the highest Data Rate is reached, the Power is decreased, so the RSSI stays above -100 dbB, which is an expected sensitivity for the highest rate.
Manual changes to the requested Power and Data Rate parameters will have no effect. The server will set these values automatically after receiving at least 20 frames with steady ADR parameters.
When the device decreases the used Data Rate, the 20 frames buffer gets flushed and the server will wait for 20 frames more before any adjustment will be made.
In this mode the server maintains for the given node the requested ADR parameters. The device is not allowed to use a different Data Rate.
If the user changes an ADR parameter, the ADR request will be sent to the node with the next downlink frame.
If the device decreases the used Data Rate, the server will send an ADR request to set this back to the requested value.
The server will enforce the requested ADR parameters by sending an ADR request with the next downlink frame and then switch to the Auto-Adjust mode.
The ADR request will be sent even if the requested ADR parameters are the same as those already used.
The server will enforce the requested ADR parameters by sending an ADR request with the next downlink frame and then switch to the Disabled mode.
The ADR request will be sent even if the requested ADR parameters are the same as those already used.
For each OTAA device you can define what ADR parameters shall be requested when the device joins the network:
- ADR Mode determines the ADR mechanism for this device;
- Set Power defines the power (in dBm) to be requested;
- Set Data Rate defines the data rate;
- Set Channels defines the set of channels to be used. The channels are given
as a comma-separated list of interfaces, e.g.
0-2(for EU) or0-71(for US). - Set RX1 DR offset defines the offset between the uplink and the RX1 slot downlink data rates
See the Device Administration guide for more details on the server administration.
After a device joins the network the server requests the ADR parameters specified in the Device ADR configuration explained above. These become the new requested Node ADR parameters, regardless of any previous settings.
Note that the requested Node parameters are not affected by an ABP device reset.
The server administration also displays the currently used ADR settings:
- Used ADR indicates whether the node can do ADR;
- Used Channels indicates the set of channels used;
- Used RX1 DR offset indicates the offset used;
- RX graph indicates the device Power (dBm), Data Rate and Frequency (MHz);
- RX Quality graph indicates the SNR (dB) and RSSI (dBm).
After a join or a reset of an ABP device the effective parameters are reverted to their standard defaults.
The ADR request to change these settings is sent to the device only when the
Use ADR is ON and when all requested ADR settings are defined (not empty).
If the device does not support (or allow) some of the requested settings, the entire request will fail. When a request fails, the requested ADR parameter(s) that caused the failure will be cleared (set to empty) and no other parameter will become effective.