LTE eNodeB Physical Layer Measurements

In LTE, the base station is known as eNodeB or eNB. Since eNodeB units are fixed, they don’t necessarily need to interact with non-LTE systems like GSM or UMTS. This means fewer measurements are usually performed on the eNodeB compared to an LTE-compliant User Equipment (UE).

This page will focus on the LTE eNodeB Physical Layer Measurements.

Downlink RS Tx Power

The Downlink Reference Signal (RS) transmit power is determined for a specific cell by taking the linear average of the power contributions (in Watts) from the resource elements. These resource elements carry cell-specific reference signals transmitted by the eNodeB within its operating system bandwidth. The measurement reference point for DL RS TX power should be the TX antenna connector.

Received Interference Power

The Uplink Received Interference Power measures the interference power and thermal noise within a Resource Block (RB) that isn’t scheduled for transmission within the cell. The absolute accuracy needs to be +/-4dB for interference measured between -117 and -96dBm. This measurement helps identify narrowband co-channel interference from neighboring cells using the same frequency.

Thermal Noise Power

The Uplink Thermal Noise Power is a broadband version of the received interference power. It is equivalent to No * W, where No represents the white noise power spectral density and W is the transmission bandwidth.