OFDMA Subcarrier Reallocation for Short Packet Overhead
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In packet-based communication systems, such as those using the Multimedia over Coaxial Alliance (MoCA) specification, short data packets perform poorly due to high preamble overhead relative to actual payload, necessitating an improved data transmission method in orthogonal frequency division multiplexed (OFDM) networks.
Innovation Solution
Implementing orthogonal frequency division multiple access (OFDMA) with dynamic bandwidth reallocation, allowing multiple transmitters to share a single preamble and reduce overhead, while enabling simultaneous data transmission using distinct subsets of OFDM subcarriers, thereby improving network throughput.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If traditional OFDM packet-based transmission is used, then long data packets achieve good performance, but short data packets perform poorly due to high preamble overhead
Solution Approach 1:
The patent segments the frequency spectrum into multiple orthogonal subcarriers, allowing the transmission bandwidth to be divided among multiple users. This segmentation enables efficient utilization of spectral resources and reduces the relative overhead impact for short packets by allowing parallel transmissions across different subcarrier sets.
Solution Approach 2:
The patent introduces a frequency-domain multiplexing dimension by assigning different subsets of subcarriers to different transmitters. This dimensional approach allows multiple packets to be transmitted simultaneously in the frequency domain, effectively reducing the time overhead proportion and improving short packet performance.
2Productivity
If multiple transmitters share the same bandwidth, then network throughput increases, but bandwidth allocation cannot adapt to current traffic patterns
Solution Approach 1:
The patent implements dynamic bandwidth allocation by allowing the network coordinator to reallocate subcarrier sets among transmitters based on current traffic conditions. The system can adaptively adjust which transmitters receive which subcarrier sets in response to changing network demands, optimizing throughput while maintaining adaptability.
Solution Approach 2:
The patent changes the bandwidth allocation parameters dynamically by modifying the subcarrier set assignments. The network coordinator can adjust the number of subcarriers allocated to each transmitter and which specific subcarriers are assigned, based on real-time traffic patterns and quality of service requirements.
3Device complexity
If fixed bandwidth allocation is used, then transmission schedule is simple, but cannot meet varying traffic requirements
Solution Approach 1:
The patent implements preliminary action by having the network coordinator pre-establish a transmission schedule that includes allocated subcarrier sets for each transmitter. This preliminary scheduling framework provides structure and simplicity while allowing for dynamic adjustments within the schedule to meet varying traffic requirements without complete redesign.
Data Source
AI summary
A method is disclosed in which a first data transmission is received at a first network node from a second network node in a coordinated network. The first data transmission is received in a first bandwidth of a coordinated network and includes a first plurality of subcarriers. A second data transmission is received at the first network node from a third network node. The second data transmission is received in a second bandwidth of the coordinated network and includes a second plurality of subcarriers. A first transmission schedule is transmitted from the first network node to the second and third network nodes. The first transmission schedule includes modified first and second bandwidths in which the modified first bandwidth includes a subcarrier reallocated from the second bandwidth. The first network node receives data in accordance with the first transmission schedule.