Adaptive tree-based contention resolution media access control protocol
US6222851A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 29, 1998 |
| Grant date | Apr 24, 2001 |
| Priority date | — |
| Expiry date | May 29, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L12/44
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
An adaptive tree-based contention resolution media access control protocol for a local area network using orthogonal frequency division multiplexing. The invention uses constant tones in frequency bins to resolve contention between multiple transmitting nodes. All nodes are synchronized to transmit "contention tones" in a "contention frame." Each node is assigned a unique identification (ID) number, and this ID number is mapped to frequency bins by transmitting a tone in each bin corresponding to each 1-bit in the binary representation of the node's ID number. The result of multiple nodes each transmitting its unique ID during a contention frame is a complex frequency signal which each participating node decodes. The nodes then participate in a "resolution frame" in which all nodes again transmit tones in frequency bins. The resolution frame tones correspond only to tones in which the result of the contention frame indicated the presence of a tone where such node had 0-valued ID bits. All nodes receive the results of the resolution frame and record the results ("resolution bits") in a reasonably-balanced binary tree. If the resolution frame contained no tones in any frequency bin, …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.