WLAN Resource Unit Allocation via Trigger Frames
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In wireless local area networks (WLANs), especially when a station (STA) is at the boundary of a basic service set (BSS) or experiences strong surrounding interference, it faces difficulties in contention-based uplink communication due to insufficient transmission power, and the access point (AP) struggles to optimize scheduling effectively.
Innovation Solution
The proposed technique involves an AP receiving control messages with recommended resource unit (RU) size, modulation and coding scheme, and uplink multi-user (UL MU) communication parameters from the STA, allowing the AP to transmit a trigger frame that determines the RU size based on these parameters, enabling the STA to perform uplink communication through a trigger-based UL MU scheme, potentially disabling contention-based access to ensure successful transmission.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a STA at the boundary of a BSS performs contention-based uplink communication, then the STA can access the channel autonomously, but the transmission fails due to insufficient transmission power
Solution Approach 1:
The access point acts as an intermediary by transmitting a trigger frame that schedules uplink multi-user communication. This trigger-based scheduling mechanism allows the AP to coordinate transmissions from multiple STAs, ensuring that boundary STAs with limited power can successfully transmit by being allocated appropriate resource units and timing, rather than relying on autonomous contention-based access.
2Adaptability or versatility
If the AP performs scheduling through a trigger frame, then the AP can control uplink communication, but it is difficult to optimize scheduling depending on the STA
Solution Approach 1:
The STA performs preliminary actions by autonomously selecting appropriate resource units and preparing uplink data before being scheduled. The trigger frame then activates this pre-prepared data for transmission. This preliminary preparation reduces the scheduling complexity at the AP while still enabling optimized scheduling, as the STA has already configured its transmission parameters based on its channel conditions and power constraints.
3Power
If the STA transmits with full bandwidth, then the data rate is high, but the transmission power is insufficient for boundary STAs
Solution Approach 1:
The uplink bandwidth is segmented into multiple resource units of different sizes. The AP allocates appropriate resource units to STAs based on their power capabilities and channel conditions. Boundary STAs with insufficient power are allocated smaller resource units that match their transmission power constraints, while STAs with sufficient power can be allocated larger resource units to achieve higher data rates. This segmentation enables both power-constrained and power-abundant STAs to operate effectively.
Data Source
AI summary
An embodiment of the present specification relates to a method and a device used in a wireless local area network (WLAN) system. For example, a WLAN station (STA) may transmit information about a preferred or recommended resource unit to an access point (AP). When a resource unit having a size which does not exceed the size of the resource unit preferred/recommended by the WLAN station is allocated for uplink communication, narrowband communication is possible, thus increasing the chance of successful uplink transmission.