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:
May. 28, 1991
Filed:
Dec. 18, 1989
Shaye Communications Limited, Hampshire, GB;
Abstract
A method of establishing a digital time-division duplex radio communication link between one of a plurality of portable units and a base unit in a cordless telephone system, transmissions from the base unit are allowed only on a ping-pong basis with transmission bursts from all the active transmitters in the base unit being synchronized with one another. This prevents blocking of receiver sections due to co-sited transmitters transmitting at the same time on a different channel. The difficulty of synchronizing the transmission bursts of the active portable units with their respective transceivers within the base unit is overcome by allowing the portable unit to make an initial continuous call comprising multiple identical sequences of data containing units small enough to be completely received within the limited reception windows of the base unit. After the initial call has started communication, an exchange of signals takes place on a ping-pong basis to establish synchronism between the portable unit and base unit. Finally, if all is well, the system reverts to a speech mode in which voice signals rather than data signals are exchanged between the portable unit and base unit.