What is Logical Antenna Port?

What is logical antenna port in LTE?
And in 5G NR?

Antenna ports do not correspond to physical antennas, but rather are logical entities distinguished by their reference signal sequences.

Multiple antenna port signals can be transmitted on a single transmit antenna (C-RS port 0 and UE-RS port 5, for example).

Correspondingly, a single antenna port can be spread across multiple transmit antennas (UE-RS port 5, for example).

Thanks for help. :wink:

Hi…an antenna port is generally used as a generic term for signal transmission under identical channel conditions. For each LTE operating mode in the downlink direction for which an independent channel is assumed (e.g. SISO vs. MIMO), a separate logical antenna port is defined.

How do we know which antenna port to use in receiver to compute channel coefficients?

Antenna port is in the 3GPP specifications an abstract concept that is a logical entity rather than a physical antenna.

Each antenna port is associated with a specific set of reference signals.

5G NR contains a different type of reference signals, like DMRS for demodulation purpose & CSI-RS for channel status reporting.

An antenna port is an indication of the type of reference signal that conveyed over the radio channel.

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