A bandwidth combination set (BWCS) in LTE Carrier Aggregation (CA) and Dual Connectivity (DC) defines the set of carrier bandwidths a User Equipment (UE) supports. This allows the network to configure CA/DC effectively, avoiding configurations that the UE cannot handle.
Essentially, the BWCS informs the network about the specific combinations of bandwidths the UE is capable of using simultaneously across multiple carriers. Without this information, the network might attempt to configure a carrier aggregation setup that exceeds the UE's capabilities, leading to connection failures or suboptimal performance.
Why are Bandwidth Combination Sets Important?
- Efficient Resource Allocation: BWCS enables the network to allocate radio resources efficiently by only assigning combinations of bandwidths that the UE can actually support.
- Improved Network Performance: By avoiding unsupported configurations, the network reduces the likelihood of connection drops and improves overall throughput.
- Optimal User Experience: BWCS ensures that users experience the best possible data rates and connectivity by enabling the network to configure carrier aggregation appropriately.
- Simplified Network Planning: BWCS simplifies network planning and optimization by providing clear guidelines on the capabilities of different UEs.
Example:
Imagine a UE that supports the following bandwidth combination set:
- Carrier 1: 20 MHz
- Carrier 2: 10 MHz
- Carrier 1: 15 MHz, Carrier 2: 15 MHz
This means the UE can operate with either a single 20 MHz carrier, a single 10 MHz carrier, or two carriers each with 15 MHz of bandwidth simultaneously. The network would then know not to try and configure, for example, two 20 MHz carriers as that configuration is not supported by this specific UE.
In Summary:
A bandwidth combination set is crucial for efficient and reliable carrier aggregation and dual connectivity in LTE and beyond. It provides the network with the necessary information about a UE's bandwidth capabilities, allowing for optimized network configurations and an improved user experience.
