Cellular TDM communication system employing offset frame synchronization

Claim 2

In an RF cellular communication system using TDM carriers, having at least a first and second cell, each cell being assigned at least one TDM carrier, a method of synchronization characterized by: providing a TDM frame for the at least first cell's carrier, providing a corresponding TDM frame for the at least second cell's carrier, and offsetting the TDM frames for the at least first carrier from that of the at least second carrier by a predetermined time.

Claim 3

The cellular TDM communication system of claim 3 wherein the corresponding TDM frame, for the at least second cell's carrier, is characterized by information whose content results from a substantially similar algorithmic operation also used to obtain information contained in the TDM frame for the at least first cell's carrier.

Claim 4

In an RF cellular system using TDM carriers, having at least a first and second cell, each cell being assigned at least one TDM carrier, and at least one subscriber unit communicating with the first cell, a method of synchronization characterized by: offsetting frame timing between the at least first and second cells by a predetermined time, establishing, at the subscriber unit, the frame offset timing used by the second cell, and transferring communication to the at least second cell based on the established offset frame timing thereby facilitating a rapid handoff.

Claim 5

The method of claim 9 wherein establishing the frame offset timing is characterized by receiving control channel information containing cell offset timing parameters from neighboring cells or sites.

Claim 6

In an RF cellular communication system using TDM carriers, having at least a first carrier transmitted by a first cell and at least a second carrier transmitted by a second cell, wherein either of the cells may be omni-directional or directional, and wherein each carrier communicates at least one traffic channel on a slot basis, a method of synchronization characterized by: offsetting frame timing between the carriers, associated with each of the plurality of cells, by a predetermined time such that frame timing for the first cell is advanced to that of the second cell, and multiplexing traffic channels for the first and second carriers into a same sequential transcoding means resulting in transcoded channels for each of the carriers, transcoding the traffic channels on a first in-first out basis, routing the transcoded channel associated with the first carrier to the first cell, and routing the transcoded channel associated with the second carrier to the second cell thereby facilitating substantially continuous transcoding of multiple traffic channel information streams.

Claim 7

In an RF cellular communication system using TDM carriers, having at least a first cell and at least one handoff cell, wherein either of the cells may be omni-directional or directional, each cell being assigned at least one TDM carrier, and at least one subscriber unit communicating with the first cell, a system apparatus for synchronization characterized by: at least one base site controller including means for offsetting frame timing between the at least first cell and the at least one handoff cell by a predetermined time, and the at least one subscriber unit having (i) means for determining the offset frame timing difference between a frame received from the at least one handoff cell and that of the at least first cell, (ii) means, operably coupled to means for determining, for establishing which particular slot information is expected in the frame received from the at least one handoff cell, and (iii) means, operably coupled to means for determining, for transferring from the TDM carrier assigned to the at least first cell, to the carrier assigned to the handoff cell, without synchronizing to a specific frame number of the at least one handoff cell thereby facilitating a rapid handoff.

Claim 8

In an RF cellular communication system using TDM carriers, having at least a first carrier transmitted by a first cell and at least a second carrier transmitted by a second cell, wherein either of the cells may be omni-directional or directional, and each carrier communicates at least one traffic channel on a slot basis, an apparatus characterized by: means for multiplexing the traffic channel streams for the first and second carriers for use in a processing means, processing means, operably coupled to the means for multiplexing, for transcoding the traffic channel input streams on a first in first out basis, means, operably coupled to the processing means, for coupling the transcoded channel associated with the first carrier to the first cell, and coupling the transcoded channel associated with the second carrier to the second cell, and means, coupled to the means for coupling, for offsetting frame timing between the carriers, associated with each of the plurality of cells, by a predetermined time such that frame timing for the first cell is advanced with respect to that of the second cell thereby facilitating substantially continuous transcoding of multiple traffic channel information streams.

Claim 9

A subscriber unit for use in an RF cellular TDM communication system having at least a first cell and handoff cell, wherein either of the cells may be omni-directional or directional, each cell being assigned at least one TDM carrier, the subscriber unit characterized by: means for determining an offset frame timing difference between a frame received from the at least one handoff cell and that of the at least first cell, and means, operably coupled to means for determining, for establishing which particular slot information is expected in the frame received from the at least one handoff cell means, operably coupled to means for determining, for transferring from the TDM carrier assigned to the at least first cell, to the carrier assigned to the handoff cell, without synchronizing to a specific frame number of the at least one handoff cell thereby facilitating a rapid handoff.

Claim 10

A subscriber unit for use in an RF cellular TDM communication system having at least a first and second cell, wherein either of the cells may be omni-directional or directional, each cell being assigned at least one TDM carrier, the subscriber unit characterized by: means for determining the offset timing difference between a frame received from the at least second cell and that of the at least first cell, means, operably coupled to means for determining, for prioritizing a search based upon the offset timings received from a plurality of neighboring cells to minimize the time to acquire subsequent neighboring cell information.