PPDU Subcarrier Assignment for HARQ Coverage Extension
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for extending coverage in radio communication, particularly in the 6-GHz band, fail to provide sufficient gain for Low Power Indoor (LPI) terminals, and existing HARQ technologies do not effectively improve reception quality due to limited power spectrum density and challenges in achieving coding gain through HARQ combination.
Innovation Solution
A communication apparatus and method that utilizes a generalized dup mode PPDU format, which assigns common data signals to multiple subchannels, combines different redundancy versions (RVs) of encoded sequences across subchannels, and employs hybrid automatic repeat request (HARQ) to enhance coverage and communication quality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If existing HARQ technologies are used to improve reception quality, then error correction capability is enhanced, but coding gain cannot be achieved due to limited power spectrum density in 6-GHz band
Solution Approach 1:
The transmission bandwidth is divided into multiple subcarrier groups, and different redundancy versions are assigned to different subcarrier groups. This segmentation allows the receiver to combine information from multiple subcarrier groups to achieve coding gain, overcoming the limitation of limited power spectrum density in the 6-GHz band.
Solution Approach 2:
The invention changes the parameter of redundancy version assignment by introducing a new field in the signal to indicate different RV assignment patterns. This enables dynamic selection of RV assignment strategies (sequential, interleaved, or random assignment) to optimize reception quality under different channel conditions and power constraints.
2Length of stationary object
If coverage is extended in radio communication, then communication range is increased, but existing methods fail to provide sufficient gain for LPI terminals
Solution Approach 1:
The invention extends coverage by utilizing the frequency dimension through subcarrier group division. By assigning different redundancy versions to different subcarrier groups and enabling the receiver to combine these diverse frequency resources, the system achieves both coverage extension and maintained communication quality for LPI terminals.
3Reliability
If common information bit is assigned to multiple subcarrier groups, then frequency diversity is achieved, but complexity of signal processing increases
Solution Approach 1:
The same information bit is copied and transmitted across multiple subcarrier groups with different redundancy versions. The receiver simply needs to combine these copies according to the indicated RV assignment pattern, which is computationally simpler than other diversity techniques while still achieving frequency diversity gain.
Data Source
AI summary
Disclosed is a communication apparatus that includes reception circuitry and control circuitry. The reception circuitry, in operation, receives a Physical Layer Convergence Procedure Protocol Data Unit, PPDU, which includes a signal field, a first data signal and a second data signal, the first data signal and the second data signal being generated from a common information bit, and the signal field including first information indicating at least one of a plurality of modes relating to assignment of the first data signal and the second data signal to a plurality of subcarrier groups. The control circuitry, in operation, processes the first data signal and the second data signal that has been assigned to the plurality of subcarrier groups, based on the first information.