PPDU Control Trailer Signaling for 802.11ay Channel Bonding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current wireless communication systems, particularly in the millimeter-wave band, face challenges in efficiently transmitting control information due to limitations in channel bandwidth and compatibility with legacy systems, especially when supporting multi-user MIMO and channel bonding features.
Innovation Solution
The method involves setting two bits in the PLCP header to indicate the presence of a control trailer, encoding this information into an LDPC codeword, and including it within the PPDU, with a Training Length field set to '2' to accommodate 18 bytes of data, allowing for channel bonding and MIMO signaling in the 802.11ay standard while maintaining backwards compatibility.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If control information is transmitted in millimeter-wave band, then data access speed is improved, but channel bandwidth limitations and compatibility with legacy systems worsen
Solution Approach 1:
The control information is segmented into two parts: a legacy header compatible with 802.11ad systems and a control trailer containing new control information. The header indicates the presence of the trailer through specific bit settings, allowing legacy systems to process the header while advanced systems can access the additional control information in the trailer for channel bonding and MIMO operations.
Solution Approach 2:
The control trailer is nested within the PPDU structure after the payload, with the legacy header containing indicators about the trailer's presence. This nested structure allows legacy systems to ignore the trailer while new systems can utilize it, enabling backward compatibility while supporting advanced features.
2Adaptability or versatility
If channel bonding and MIMO features are supported, then communication capabilities are improved, but device complexity worsens
Solution Approach 1:
The control trailer uses a universal structure that can carry multiple types of control information for different features (channel bonding, MIMO, etc.) through a standardized format. The Training Length field and other control fields provide a multi-functional framework that handles various advanced features without requiring separate mechanisms for each, reducing overall system complexity.
3Loss of information
If Training Length field is set to accommodate control trailer, then control information transmission is improved, but overhead in header worsens
Solution Approach 1:
The Training Length field is set to a specific value (2) that provides sufficient capacity for the control trailer (18 bytes) while avoiding excessive allocation. This partial action approach allocates just enough header overhead to accommodate the control information needs without unnecessary expansion, balancing information transmission requirements with overhead constraints.
Data Source
Figure 1
Figure 2~3
Figure 4
AI summary
Some demonstrative embodiments include apparatuses, devices, systems and methods of communicating control information in a Physical Layer Convergence Protocol (PLCP) Protocol Data Unit (PPDU). For example, an apparatus may include logic and circuitry configured to cause a wireless station to generate a PPDU comprising a header field, a payload after the header field, and a control trailer after the payload, the control trailer comprising control information, the header field indicating presence of the control trailer; and to transmit the PPDU over a directional wireless communication band.