Power gain and sensitivity

When configuring a node and a network, one important parameter is related with the Received Signal Strength Indicator (RSSI).

Received Signal Strength Indicator

This command reports the received signal strength of the last received RF data packet. The getRSSI() command only indicates the signal strength of the last hop. It does not provide an accurate quality measurement for a multihop link. The command value is measured in -dBm. For example if it returns 0x60, then the RSSI of the last packet received was -96 dBm.

Example of use:

{
    xbee900HP.getRSSI();
}

Related variables:

xbee900HP.valueRSSI → stores the RSSI of the last received packet

The ideal working mode is getting maximum coverage with the minimum power level. Thereby, a compromise between power level and coverage appears. Each application scenario will need some tests to find the best combination of both parameters.

Get RSSI example:

https://development.libelium.com/waspmote/900hp-05-get-rssi

Power level

It is possible to set/get the power level at which the RF module transmits conducted power. Power level 4 is calibrated and the other power levels are approximate.

Parameter range:

0 = +7 dBm, (5 mW) 1 = +15 dBm, (32 mW) 2 = +18 dBm, (63 mW) 3 = +21 dBm, (125 mW) 4 = +24 dBm, (250 mW) [Default]

Example of use:

{
    xbee900HP.setPowerLevel(4);
    xbee900HP.getPowerLevel();
}

Related variables:

xbee900HP.powerLevel → Stored the power level set

Power level example:

https://development.libelium.com/waspmote/900hp-12-set-power-level