Method and equipment for bidirectional data transmission (protocol)
US5515035A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 24, 1994 |
| Grant date | May 7, 1996 |
| Priority date | — |
| Expiry date | Jan 24, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04W74/08
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
With this method, a CSMA/CA protocol can be used for the transmission of data by means of infra-red light or radio (or other non-hard-wired transmission media). For this purpose a communicator that has a transmit requirement and has not yet received a bit identifies itself as an initiating communicator, and one that has no transmit requirement but has received a bit identifies itself as a receiving communicator. At the start of data transmission the initiating communicator sends a double length start bit (D) representing its identity and then waits a defined time (tc), during which the receiving communicator sends back an echo in the form of a single length start bit (B). The initiating communicator waits after each bit transmitted for the echo and compares this on receipt with the transmitted bit, its transmission being interrupted after a mismatch. After the data transmission, and provided there is no further transmit requirement, the identities of initiating and receiving communicators are removed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.