Down-link transmission inter-cell scheduling in CDMA data networks

A base station of a cell in a network of cells, the base station including apparatus for allocating a transmission time interval to a corresponding user, for transmission of a spread data signal to the user by a given base station of a given cell, the apparatus comprising:

• measuring module that determines a set of interference patterns for the given cell related to signal transmission characteristics between the corresponding user and one or more base stations of the network of cells, each cell of the network of cells having users and a base station capable of transmitting one or more spread data signals to such users,
• wherein the signal transmission characteristics between the user and one or more base stations of the network of cells are one or more of a path loss gain, a signal-to-interference noise threshold, a transmission spectrum, and an orthogonality factor;
• and
• a processing module comprising
• a first sub-module that solves, in accordance with an optimizing criterion, a linear programming problem defined by (i) the set of interference patterns and (ii) a set of constraints for allocated time intervals based on the set of interference patterns, thereby to determine the time interval to be allocated;
• and
• a second sub-module that, responsive to the solution of the linear programming problem, allocates a recurrent time interval for the given base station to transmit therewithin spread data signals to the corresponding user, such that the recurrent time interval overlaps no time interval allocated to any other individual user belonging to the given cell.

A computer-readable medium having stored thereon a plurality of instructions, the plurality of instructions including instructions which, when executed by a processor, cause the processor to implement a method of allocating a transmission time interval to a corresponding user, for transmission of a spread data signal to the user by a given base station of a given cell in a network of cells, the method comprising the steps of:

• a) defining a set of interference patterns for the given cell related to signal transmission characteristics between the corresponding user and one or more base stations of the network of cells, each cell of the network of cells having users and a base station capable of transmitting one or more spread data signals to such users,
• wherein the signal transmission characteristics between the user and one or more base stations of the network of cells are one or more of a path loss gain, a signal-to-interference noise threshold, a transmission spectrum, and an orthogonality factor;
• b) solving, in accordance with an optimizing criterion, a linear programming problem defined by (i) the set of interference patterns and (ii) a set of constraints for allocated time intervals based on the set of interference patterns, thereby to determine the time interval to be allocated;
• and
• c) responsive to the solution of the linear programming problem, allocating a recurrent time interval for the given base station to transmit therewithin spread data signals to the corresponding user, such that the recurrent time interval overlaps no time interval allocated to any other individual user belonging to the given cell.