Physical Layer Multicast Group Addressing for Wi-Fi Power Savings
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current wireless communication networks lack a means to address and identify multicast groups at the physical layer, leading to unnecessary processing of multicast packets by all devices, which wastes resources and prevents power-saving modes in non-intended client devices.
Innovation Solution
Reusing an existing field in the IEEE 802.11ac PLCP header to indicate multicast group transmissions, allowing client devices to identify and drop non-intended packets early, thereby enabling PHY-layer multicast group addressing without modifying the standard.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If multicast frames are processed by all devices from physical layer to MAC layer, then all devices can receive the data, but all devices consume power unnecessarily including those not intended to receive the multicast transmission
Solution Approach 1:
The patent applies preliminary action by placing group identification information in the PLCP header before the actual data transmission. This allows receiving devices to identify whether they belong to the target multicast group before processing the entire frame, enabling them to discard non-intended packets early at the physical layer and avoid unnecessary power consumption during MAC layer processing.
Solution Approach 2:
The patent extracts the group identification information from the MAC layer and places it in the physical layer header (PLCP header). This extraction allows devices to filter multicast packets at the physical layer based on group ID matching, separating intended recipients from non-intended devices before full frame processing occurs, thereby reducing energy consumption for devices not in the target group.
2Productivity
If group identification information is placed in the PLCP header, then devices can identify and drop non-intended packets early at physical layer, but this requires reusing existing header fields which may limit addressing flexibility
Solution Approach 1:
The patent applies universality by reusing the existing GID (Group ID) field in the PLCP header, which was originally designed for other purposes, to carry multicast group identification information. This multi-functional use of the existing header field enables early packet filtering and power savings without requiring modifications to the IEEE 802.11ac standard or adding new header structures.
3Loss of energy
If multicast addressing is implemented at physical layer, then power savings are enabled for non-intended devices, but this requires modifying packet structure which may impact compatibility with existing standards
Solution Approach 1:
The patent reuses the existing GID field in the PLCP header for multicast group identification, leveraging the existing IEEE 802.11ac physical layer structure. This approach enables physical layer multicast filtering and power savings while maintaining full compatibility with the existing standard, as no modifications to the standard structure are required.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Techniques are provided to enable group addressing for multicast transmissions in a frame that is configured to support multi-user transmissions. The frame comprises a header field that is configured to indicate to recipient devices associated with a multi-user transmission interval during which time, frequency and spatial channel resources are allocated to allow for the transmission of a data frame or simultaneous transmission of corresponding ones of a plurality of data frames to respective recipient devices. In the header field, group identification information is wirelessly transmitted that indicates a group of recipient devices which are to receive a transmission during the multi-user transmission interval. Data is wirelessly transmitted for a multicast transmission during the multi-user transmission interval that follows the header field, where the multicast transmission is intended for a group of recipient devices that are members of a multicast group corresponding to the group identification information contained in the header field.