What is logical antenna port in LTE?
And in 5G NR?
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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).
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Thanks for help. 
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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.
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How do we know which antenna port to use in receiver to compute channel coefficients?
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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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Hi Experts.
What is difference between Antenna Logical and Physical Ports?
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Logical ports for smart antennas like p7, p8 for tm8.
You can say it virtual ports as well.
Physical antenna what i understood which are non smart ie not for beamforming.
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Reference signals are assigned to Logical antenna ports and each logical antenna ports are having unique postioning of reference signals.
Whereas physical antenna ports are number of RF output ports at RRH/RRU end.
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Thanks.
Now, what is the difference between Layer, Logical port, Antenna Ports and Physical Antenas?
How are they interconnected?
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You have to read 3gpp for this.
There are antenna ports 1000 then 3000.
Also csi-rsports are involved.
Keep in mind these: there can be 4 layers for one UE and 4, 8, 16 or 32 csi-rs ports and up to 384 antenna elements.
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Thanks. Which 3gpp?
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- Layer: on which codeword transfer.
- Logical port: with smart antennas mainly introduced with beamforming concept with tm7 in LTE.
- Antenna port: with passive antenna where we have 2,4 ports antenna.
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In 5G New Radio (NR), antenna ports play a crucial role in facilitating wireless communication between the base station (gNB) and user equipment (UE). There are two types of antenna ports in 5G NR: logical antenna ports and physical antenna ports. Let’s explore each of them:
1-Logical Antenna Ports:
Logical antenna ports are virtual ports defined at the protocol level to represent different types of transmission and reception within the 5G system. These ports are used for higher-layer signaling and are not directly associated with any physical radio frequency (RF) interfaces. Logical antenna ports are classified into two main categories:
Downlink Logical Antenna Ports:
-Port 100: This logical antenna port is used for downlink transmission of the Primary Synchronization Signal (PSS), Secondary Synchronization Signal (SSS), and broadcast channel information.
-Port 200: This logical antenna port is used for downlink transmission of the Physical Broadcast Channel (PBCH) and System Information Blocks (SIBs).
-Port 300 to Port 400: These logical antenna ports are used for downlink transmission of various channels, such as the Physical Downlink Shared Channel (PDSCH) and Physical Multicast Channel (PMCH).
Uplink Logical Antenna Ports:
-Port 1000: This logical antenna port is used for uplink transmission of the Physical Random Access Channel (PRACH) and Random Access Response (RAR).
-Port 2000: This logical antenna port is used for uplink transmission of the Physical Uplink Control Channel (PUCCH).
-Port 3000 to Port 4000: These logical antenna ports are used for uplink transmission of various channels, such as the Physical Uplink Shared Channel (PUSCH) and Physical Multicast Channel (PMCH).
2-Physical Antenna Ports:
Physical antenna ports are associated with the actual RF interfaces of the base station and user equipment. These ports correspond to the physical connectors or interfaces where the antennas are connected. Physical antenna ports are responsible for the transmission and reception of radio signals between the gNB and 
UE. In the 5G NR standard, physical antenna ports are numbered from 0 to 255.
It’s important to note that the mapping between logical antenna ports and physical antenna ports is defined by the 5G NR standard and may vary depending on the specific deployment scenario and configuration of the network.
Credits: 
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This is with regard to the fundamental doubt many still have on the difference between Layers, Ports and Antennas.
Many have come across 4 different terms and are not able to differentiate between them practically.
The terms are
Layer
Logical Ports
Antenna Ports
Physical Antennas
Could anyone here please explain to us here what is the prime difference between these terms and how they are used in LTE/5G NR and how is mapping done between Layers all the way up to Physical Antennas.
With an example would be great. 
The answer to all your questions is at this page:
https://www.sharetechnote.com/html/5G/5G_CSI_RS_Codebook.html
Try to understand this picture:
