The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 10, 1997
Filed:
Dec. 12, 1995
Motorola, Inc., Schaumburg, IL (US);
Abstract
A communications system is described having a number of communicating units arranged for communication over a common communications channel. A first communicating unit (10) transmits a data transmission (104) followed by an end-of-data indication (102) and a predetermined period of further transmission activity (101) to a second communicating unit (12). During the period of further transmission activity (101) of the first unit, the second unit seizes the channel (103) and transmits a preamble (105) prior to its response data. This process continue ensuring that periods of further transmission activity (101) and the preamble (105) keep the channel open for the duration of the communication, for sole use by the communicating units. The invention is applicable to, but not limited to use in supervisory control and acquisition-of-data (SCADA) systems.