Resource Element Group in LTE
In Long-Term Evolution (LTE), Resource Element Group (REG) is a fundamental concept related to physical layer resources. It is essentially a grouping of Resource Elements (REs), which are the smallest units of the time-frequency grid in LTE. The REG is used to allocate resources for transmission and reception.
Now, let’s break down the key components:
- Resource Element (RE): The basic building block in LTE’s time-frequency grid. It represents a single modulation symbol in a resource block.
- Resource Block (RB): A collection of consecutive REs in the time and frequency domain. It is the basic unit for resource allocation in LTE.
- Resource Element Group (REG): A set of contiguous REs within a resource block. REGs are used for certain reference signals, such as cell-specific reference signals (CRS) and UE-specific reference signals (UE-RS).
The grouping of REs into REGs allows for efficient resource allocation and reference signal transmission. It aids in signal demodulation and provides a structured way to organize the physical layer resources in LTE.
In summary, the Resource Element Group (REG) is a grouping of Resource Elements (REs) within a Resource Block (RB), playing a crucial role in LTE’s physical layer for efficient resource allocation and signal transmission.
- For the control channel, the radio signaling, the Resource Block is not the adapted unit.
- The control channels mapped on the Resource Elements Groups (REGs), which represent less radio resources
- A REG is made up of 4 (or 6 if there are pilot sub-carriers) sub-carriers during 1 symbol.
- The REG are grouped into the CCE (Control Channel Element)
Resource element groups are sued for defining the mapping of control channels to resource elements.