Abstract: In a wireless TDMA network a control module (CM) sends a time stamp relative to the beginning of its frame in a synchronization packet allowing each of a plurality of user modules (UM) to maintain synchronization relative to the CM. The CM uses a plurality of directional antennas and transmits the synchronization packets over each antenna over a predetermined number of frames. The UMs use a receive time stamp to identify the beginning of a received synchronization packet. The difference between the time stamps combined with a delay constant is used by the UMs to adjust time synchronization to the CM frame.

Abstract: A hierarchical addressing technique is employed in a packet communications system to enhance flexibility in storing and referencing packet information. This method permits packet message data and certain packet control data to be stored in memory locations without having to be duplicated at a different memory location prior to transmission of the packet. This method is preferably employed in a ring configuration in which a series of packets have addressing mechanisms which points sequentially to each other to form a ring of packets received or to be transmitted.

Abstract: An RF communication system contains a control module which communicates with a plurality of user modules that are each connected to at least one user device. The system provides a method for packet communications in which traditional destination addressed packets are communicated to the specified destination point or user module while also permitting information intended for a plurality of user modules to be broadcast simultaneously to all user modules using a broadcast protocol. The probability of each UM receiving the broadcast packet is enhanced by the transmission by the control module of each broadcast packet over at least several of its directional antennas and preferably repeated over each antenna a number of times. Packets of data which are longer than a predetermined number of bytes are broken into packet fragments.

Abstract: An antenna selection technique is used in an RF communincation system in which user modules (UM) communicate with at least one node. The UM's and nodes each have multiple antennae. The combination of each UM and node antenna is evaluated at the UM. Based on at least signal quality, the UM selects its antenna and the best node antenna for use. An alternate antenna is selected if a person is determined to be present in a predetermined area adjacent a UM corresponding to a predetermined RF power level.

Abstract: An antenna selection technique is used in an RF communication system in which user modules (UM) communicate with at least one node. The UM's and nodes each have multiple antennae. The combination of each UM and node antenna is evaluated at the UM. Based on both signal quality and strength, the UM selects its antenna and the best node antenna for use.