Extended USF addressing space

A method of assigning addresses to a plurality of communication devices in a radio access network for use in notification of scheduled uplink transmission time periods for the communication devices, the method comprising, for a plurality of communication devices in a first set of communication devices:

• assigning a common uplink state flag (USF) to every communication device in the first set;
• and
• assigning a unique extended USF (eUSF) value to each communication device in the first set;
• wherein the address assigned to the communication device is a combination of the assigned USF value and the assigned eUSF value.

A method in a radio access network of notifying a plurality of communication devices of uplink transmission time periods scheduled for the communication devices, the method comprising:

• sending, to a first set of the communication devices, a common uplink state flag (USF) value assigned to all of the communication devices in the first set;
• and
• sending, to each of the communication devices in the first set, an extended USF (eUSF) value assigned to the communication device, wherein a unique eUSF value is sent to each of the communication devices in the first set;
• whereby the communication devices are notified that they have been granted uplink transmission opportunity in a subsequent time period.

A control unit for use in notification of scheduled uplink transmission time periods for communication devices in a radio access network, wherein said control unit comprises a processor that is adapted to, for each communication device in a first set of communication devices:

• assign to the communication device an uplink state flag (USF) value;
• and
• assign to the communication device an extended USF (eUSF) value;
• wherein the address assigned to the communication device is a combination of the assigned USF value and the assigned eUSF value;
• wherein the processor is adapted to select the USF value from a set of one or more legacy USF values, wherein each of the legacy USF values of said set can be assigned to a plurality of communication devices;
• and
• wherein the processor is adapted to select the eUSF value as an eUSF value that uniquely identifies the communication device among a plurality of communication devices having the same assigned legacy USF value.