LTE Base Station Channel Allocation for Asymmetric UL-DL Bands
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In 3GPP LTE-Advanced systems with asymmetric communication bandwidths between uplink and downlink, the use efficiency of frequency resources is degraded due to redundant placement of PHICH and PDCCH channels, leading to increased overhead and inefficient resource allocation.
Innovation Solution
An LTE+ base station assigns resource allocation information to PDCCHs in respective downlink component bands and places PHICHs in a same number of partial downlink component bands as the number of uplink component bands, allowing terminals to map uplink data and extract response signals from corresponding PHICHs, optimizing channel placement for efficient use of frequency resources.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If the number of uplink unit bands is reduced to improve frequency usage efficiency, then frequency usage efficiency is improved, but the system must handle asymmetric communication bandwidths which increases complexity in resource allocation
Solution Approach 1:
The system segments downlink unit bands and uplink unit bands as separate frequency resources. The base station allocates different numbers of downlink unit bands (e.g., 4 bands) and uplink unit bands (e.g., 2 bands) independently, allowing asymmetric bandwidth configuration. This segmentation enables efficient frequency usage by matching resource allocation to actual communication needs while maintaining separate management for each direction.
Solution Approach 2:
The patent implements asymmetric bandwidth configuration where the number of downlink unit bands differs from the number of uplink unit bands. Specifically, more downlink unit bands are allocated than uplink unit bands to match typical communication patterns where downlink traffic exceeds uplink traffic. This asymmetric allocation improves frequency usage efficiency by avoiding waste of uplink resources while maintaining sufficient downlink capacity.
Solution Approach 3:
The system introduces the dimension of cross-band resource allocation by mapping multiple downlink unit bands to fewer uplink unit bands. Resource allocation information and response signals are distributed across multiple downlink bands and associated with corresponding uplink bands through defined mapping relationships. This dimensional approach allows efficient resource utilization across the frequency spectrum while managing asymmetric bandwidth requirements.
2Productivity
If multiple downlink unit bands are used to increase communication capacity, then communication capacity is improved, but the number of response signals that must be managed increases
Solution Approach 1:
The patent merges the management of multiple downlink unit bands with a reduced set of uplink unit bands. Response signals from multiple downlink bands are consolidated and mapped to corresponding uplink bands through systematic mapping relationships. This merging reduces the total number of response signals that need to be independently managed while maintaining the communication capacity provided by multiple downlink bands.
Solution Approach 2:
The system establishes cross-band mapping relationships between downlink unit bands and uplink unit bands. Resource allocation information and response signals are organized in a multi-dimensional structure where multiple downlink bands map to fewer uplink bands. This dimensional organization allows the system to handle multiple downlink bands for high communication capacity while managing response signals through a reduced uplink band structure.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Disclosed is a base station in which the frequency usage efficiency can be improved when the communication bandwidths are asymmetric in the uplink line and the downlink line. A base station (200) can communicate by using a plurality of downlink unit bands and a smaller number of uplink unit bands. A control unit (201) allocates uplink resource allocation information and downlink resource allocation information to a PDCCH which is arranged in each of the plurality of downlink unit bands, and allocates a response signal to the uplink line data to a PHICH which is arranged in the same number of downlink unit bands from the plurality of downlink unit bands as there are uplink unit bands. A transmit RF unit (212) transmits the resource allocation information or the response signal.