L-SIG Field Training Tone Insertion for 802.11ax Capacity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Next-generation 802.11ax wireless communication systems are limited by legacy protocols that restrict the number of tones available for data transmission, resulting in reduced data capacity due to insufficient training tones for channel estimation.
Innovation Solution
The method involves generating an L-SIG field with data and pilot tones, inserting additional training tones before and after the data and pilot tones, and managing power in the time domain to balance the L-LTF field with the L-SIG field, allowing for increased data tones by adding up to four additional training tones, which provide channel estimates for data fields.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If additional training tones are added to increase data capacity, then the number of data tones increases, but the power distribution becomes unbalanced
Solution Approach 1:
The patent changes the power parameter of the L-SIG field by increasing its power level to compensate for the addition of training tones. This parameter adjustment maintains overall power balance while enabling increased data tones in the HE-WPSG field, directly resolving the contradiction between quantity increase and power distribution balance.
2Measurement precision
If training tones are increased for better channel estimation, then channel estimation accuracy improves, but legacy compatibility is compromised
Solution Approach 1:
The patent segments the signal structure into legacy-compatible portions (L-SIG with training tones) and new-protocol portions (HE-WPSG). By adding training tones specifically to the L-SIG field which is part of the legacy-compatible preamble structure, the system improves channel estimation without breaking legacy compatibility, as legacy devices can still process the segmented structure appropriately.
Solution Approach 2:
The L-SIG field acts as an intermediary between legacy protocols and new 802.11ax features. By embedding training tones within the L-SIG field structure, it mediates between the need for improved channel estimation (new feature) and legacy protocol compatibility (old requirement), allowing both objectives to be achieved simultaneously.
3Quantity of substance
If power is increased in L-SIG field to accommodate additional tones, then data capacity increases, but energy consumption increases
Solution Approach 1:
The patent applies partial power increase only to the L-SIG field portion that contains the additional training tones, rather than increasing power across the entire signal. This partial action approach enables the necessary data capacity increase while minimizing overall energy consumption by limiting the power boost to only where needed.
Data Source
AI summary
Accordingly, systems and methods for managing power when the number of training and data tones are increased in a wireless communications system are provided. An L-SIG field is generated that includes a set of data and pilot tones, wherein the pilot tones are inserted between the data tones in the set of data and pilot tones. A plurality of training tones is added to the L-SIG field before and after the set of data and pilot tones. A symbol is generated that includes the L-SIG field, an L-LTF field, and a data field, wherein the training tones of the L-SIG field provide channel estimates for the data field. Power of the L-LTF field is managed relative to power of the L-SIG field in the generated symbol in a time domain.