Random access protocol for multi-media networks
US5453987A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 15, 1994 |
| Grant date | Sep 26, 1995 |
| Priority date | — |
| Expiry date | Feb 15, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2012/6494
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A protocol for mixed voice and data access to a synchronous broadcast communications channel (116) is provided. Transmission on the broadcast communications channel (116) is by means of a plurality of time division frames, each such frame being defined by a plurality of time slots (210). The protocol requires that a user determine whether a time slot is available. If a slot is available, a user transmits a preamble (212) on the broadcast communications channel and then substantially simultaneously monitors the channel for determining whether a collision of the preamble has occurred. If a collision has occurred with a second user who has a higher priority, the first user reattempts to acquire an available time slot after a time delay, the time delay being equivalent to a random number of time slots. If on the other hand, the collision was with a second user of equal priority, both users will reattempt acquisition of available time slots after respective random time delays. The preambles of users of different priority are transmitted using a non-interfering code or modulation frequency, thereby allowing the higher priority user to continue transmission of the remaining fields which m…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.