Base Station Resource Allocation Using Predicted SINR
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In communication systems, particularly in IEEE 802.16-based OFDMA systems, base stations face challenges in efficiently allocating radio resources using space division multiplexing (SDM) with multiple antennas, as they struggle to determine proper modulation and coding schemes due to uncertainty in signal-to-interference-and-noise ratio (SINR) before packet transmission, especially when transmission frames are short and service priorities need to be considered.
Innovation Solution
A method is introduced where the base station receives channel quality information from terminals, predicts the SINR using channel response and antenna weights, and allocates resources accordingly. This involves calculating antenna weights using methods like maximum ratio transmission (MRT) and zero forcing (ZF) for downlink, and maximal ratio combining (MRC) and minimum mean square error (MMSE) for uplink, to select appropriate modulation and coding schemes based on predicted SINR.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the base station performs scheduling and resource allocation through a process that requires a lot of calculation and time to improve spectrum efficiency, then spectrum efficiency is improved, but the allocation time and calculation complexity increase
Solution Approach 1:
The base station performs preliminary actions by acquiring channel quality information (CQI) from terminals before actual resource allocation. The terminal measures channel quality on downlink preamble or pilot signals and feeds back CQI, which includes channel quality metrics and recommended modulation and coding schemes. This preliminary information gathering enables faster subsequent allocation decisions without requiring complex real-time calculations during the allocation moment itself.
2Measurement precision
If the base station acquires radio channel information and searches for groups of terminals to spatially divide, then resource allocation accuracy is improved, but the calculation complexity and processing time increase
Solution Approach 1:
The patent introduces channel quality information (CQI) as an intermediary element that mediates between the complex channel state and the resource allocation decision. The terminal measures the actual channel quality and compresses this information into CQI metrics, which then guide the base station's allocation process. This intermediary simplifies the base station's task by providing pre-processed, actionable information without requiring the base station to perform complex channel measurements and terminal group searches.
3Speed
If the base station allocates radio resources before packet transmission, then resource allocation is performed in time, but the base station cannot determine proper modulation and coding scheme due to unknown SINR
Solution Approach 1:
The base station performs preliminary action by having the terminal measure channel quality on downlink preamble or pilot signals before actual data transmission. The terminal calculates channel quality information (CQI) based on these preliminary signals and feeds it back to the base station. This allows the base station to determine appropriate modulation and coding schemes in advance, enabling timely resource allocation without waiting for actual packet transmission to estimate SINR.
Data Source
AI summary
A base station using multiple antennas receives channel quality information from a terminal so as to allocate uplink/downlink resources to the terminal. Herein, the channel quality information is measured on the basis of a downlink preamble or pilot signal, and may include a received CINR or received signal strength. In addition, the base station predicts a received SINR by using a channel response and channel quality information between the multiple antennas and the terminal, and allocates a resource to the terminal according to the received SINR.