Simplex communication

Abstract: The present invention provides a method and apparatus for establishing point-to-point full duplex communication between two stations served by a local area network (LAN) or connected by a communication link. One station initially transmits a request message through the link. The request message indicates that a first station is available for full duplex communication and also serves as a test to determine whether any non-full duplex devices are present along the point-to-point link between the first station and a second station. A second station receives the request message and responds by transmitting a reply message which indicates its availability for full duplex communication. Subsequently, full duplex communication may commence. The two stations periodically exchange additional messages to continuously verify that full duplex communication is operating properly.

Abstract: Communications within a computer network may be controlled by determining that conditions within a first communication channel communicatively coupling components of the computer network are becoming unacceptable for continued utilization of the communication channel and then switching communications within the computer network to a second communication channel. Interference conditions therein preferably being less severe than interference conditions within the first communication channel. The switching may be initiated by one of the network components and generally includes placing communications within the first communication channel in a standby condition while searching for an available communication channel. This may be accomplished by instructing the components of the computer network to remain quiet while one of the components searches for an available communication channel, for example by tuning an associated radio to listen in the second communication channel. Ultimately, network communications may be established in the second communication channel. This may include setting up bandwidth connection agreements with each of the components of the computer network for the second communication channel and/or polling for each of the components of the computer network in the second communication channel.

Abstract: A radio telephone communication system (200) having a base station (203) and at least one radio telephone (100) capable of communicating with each other over at least one radio frequency channel. To determine the acquisition status of a radio frequency channel, a radio telephone (100) provides an indication representing a channel busy status (402) when one of the following occurs: a communication link request fails and bidirectional communication exists on the radio frequency channel; a communication link request fails and unidirectional communication originating from the base station exists on the radio frequency channel; and communication including at least a signal validly transmitted only by the base station exists on the radio frequency channel.

Abstract: A two-way radio communications system of the simplex or half-duplex type having a communication link to a duplex telephone system is provided wherein the simplex or half duplex mobile radio is provided priority to talk upon demand. The communication link is provided without the time delays inherent in conventional systems.