Cellular

CellularSignal Class

This class allows to query a number of signal parameters of the currently connected Cellular network.

getAccessTechnology()

// SYNTAX
CellularSignal sig = Cellular.RSSI();
int rat = sig.getAccessTechnology();

Gets the current radio access technology (RAT) in use.

The following radio technologies are defined:

• NET_ACCESS_TECHNOLOGY_GSM: 2G RAT
• NET_ACCESS_TECHNOLOGY_EDGE: 2G RAT with EDGE
• NET_ACCESS_TECHNOLOGY_UMTS/NET_ACCESS_TECHNOLOGY_UTRAN/NET_ACCESS_TECHNOLOGY_WCDMA: UMTS RAT
• NET_ACCESS_TECHNOLOGY_LTE: LTE RAT
• NET_ACCESS_TECHNOLOGY_LTE_CAT_M1: LTE Cat M1 RAT

getStrength()

Gets the signal strength as a percentage (0.0 - 100.0). See getStrengthValue() on how raw RAT-specific strength values are mapped to 0%-100% range.

// SYNTAX
CellularSignal sig = Cellular.RSSI();
float strength = sig.getStrength();

// EXAMPLE
CellularSignal sig = Cellular.RSSI();
Log.info("Cellular signal strength: %.02f%%", sig.getStrength());

Returns: float

getQuality()

Gets the signal quality as a percentage (0.0 - 100.0). See getQualityValue() on how raw RAT-specific quality values are mapped to 0%-100% range.

// SYNTAX
CellularSignal sig = Cellular.RSSI();
float quality = sig.getQuality();

// EXAMPLE
CellularSignal sig = Cellular.RSSI();
Log.info("Cellular signal quality: %.02f%%", sig.getQuality());

Returns: float

Note: qual is not supported on 2G Electrons (Model G350) and will return 0.

LTE Cat M1 devices (SARA-R410M-02B modem) only return qual with Device OS 1.5.0 and later. Earlier versions returned 0.

getStrengthValue()

// SYNTAX
CellularSignal sig = Cellular.RSSI();
float strength = sig.getStrengthValue();

Gets the raw signal strength value. This value is RAT-specific. See getAccessTechnology() for a list of radio access technologies.

• 2G RAT / 2G RAT with EDGE: RSSI in dBm. Range: [-111, -48] as specified in 3GPP TS 45.008 8.1.4.
• UMTS RAT: RSCP in dBm. Range: [-121, -25] as specified in 3GPP TS 25.133 9.1.1.3.
• LTE Cat M1 RAT: Range: [-141, -44] (dBm)
• LTE Cat 1 RAT: Range: [-141, -44] (dBm)

Returns: float

getQualityValue()

// SYNTAX
CellularSignal sig = Cellular.RSSI();
float quality = sig.getQualityValue();

Gets the raw signal quality value. This value is RAT-specific. See getAccessTechnology() for a list of radio access technologies.

• 2G RAT: Bit Error Rate (BER) in % as specified in 3GPP TS 45.008 8.2.4. Range: [0.14%, 18.10%]
• 2G RAT with EDGE: log10 of Mean Bit Error Probability (BEP) as defined in 3GPP TS 45.008. Range: [-0.60, -3.60] as specified in 3GPP TS 45.008 10.2.3.3.
• UMTS RAT: Ec/Io (dB) [-24.5, 0], as specified in 3GPP TS 25.133 9.1.2.3.
• LTE Cat M1 RAT: Range: [-20, -3] (dB)
• LTE Cat 1 RAT: Range: [-20, -3] (dB)

Returns: float

Note: qual is not supported on 2G Electrons (Model G350) and will return 0.

Before 0.8.0:

Before Device OS 0.8.0, the CellularSignal class only had two member variables, rssi, and qual. These are removed in Device OS 3.0.0 and later and you should use getStrengthValue() and getQualityValue() instead.

// Prior to 0.8.0:
CellularSignal sig = Cellular.RSSI();
Serial.println(sig.rssi);
Serial.println(sig.qual);