CHANNEL DIVISION

1 . A communication device that forms part of a network comprising a plurality of cells, each comprising a communication device configured to communicate with at least one terminal via a frequency hopping sequence associated with its respective cell, the communication device being configured to, responsive to a determination that there are an insufficient number of frequencies available to provide frequency hopping sequences for it and the communication devices in its neighbouring cells that are sufficiently distinct from each other, share the insufficient number of frequencies with those communication devices on a time division basis.

2 . A communication device as claimed in claim 1 , configured to share the insufficient number of frequencies with its neighbouring communication devices responsive to a communication from a network controller.

3 . A communication device as claimed in claim 2 , configured to share the frequencies responsive to a command from the network controller.

4 . A communication device as claimed in claim 2 , configured to determine that it should share the frequencies responsive to a frequency hopping sequence received from the network controller, responsive to the number of frequencies comprised in the frequency hopping sequence being below a predetermined threshold.

5 . (canceled)

6 . A communication device as claimed in claim 1 , configured to negotiate with its neighbouring communication devices to determine how the insufficient number of frequencies should be shared between them.

7 . A communication device as claimed in claim 1 , configured to:

communicate with the at least one terminal comprised in its cell via a series of frames, each frame comprising a downlink portion and an uplink portion; and

share the insufficient number of frequencies with its neighbouring communication devices by communicating the downlink portion of a frame in one timeslot on a frequency in its frequency hopping sequence and the uplink portion of the same frame in a different timeslot on the same frequency.

8 . A communication device as claimed in claim 67 , configured to communicate the downlink portion and the uplink portion of the frame in timeslots arranged such that the time from the start of the timeslot for the downlink portion to the end of the timeslot for the uplink portion is less than or equal to the duration of a frame via which the communication device normally communicates with the at least one terminal.

9 . A communication device as claimed in claim 6 , configured to communicate the downlink portion and the uplink portion of the frame in timeslots that are separated by one or more timeslots allocated to its neighbouring communication device(s), such that the at least one terminal perceives the one or more timeslots allocated to the neighbouring communication device(s) as being parts of the frame that are allocated to other terminals in the cell.

10 . (canceled)

11 . A communication network comprising:

a plurality of cells, each comprising a communication device configured to communicate with at least one terminal via a frequency hopping sequence associated with its respective cell;

each communication device being further configured to, responsive to a determination that there are an insufficient number of frequencies available to provide frequency hopping sequences for it and the communication devices in neighbouring cells that are sufficiently distinct from each other, share the insufficient number of frequencies with those communication devices on a time division basis.

12 . A communication network as claimed in claim 9 , comprising, in each of the plurality of cells, a communication device that forms part of a network comprising a plurality of cells, each comprising a communication device configured to communicate with at least one terminal via a frequency hopping sequence associated with its respective cell, the communication device being configured to, responsive to a determination that there are an insufficient number of frequencies available to provide frequency hopping sequences for it and the communication devices in its neighbouring cells that are sufficiently distinct from each other, share the insufficient number of frequencies with those communication devices on a time division basis.

13 . A communication network as claimed in claim 9 , configured to determine that there are an insufficient number of frequencies available for a group of two or more neighbouring communication devices if the frequency hopping sequences derivable from those available frequencies require two or more neighbouring communication devices to use the same frequency for a length of time that is likely to lead to unacceptable packet loss.

14 . A communication network as claimed in claim 9 , comprising a controller configured to determine that there are an insufficient number of frequencies available to provide frequency hopping sequences for a group of two or more neighbouring communication devices.

15 . A communication network as claimed in claim 11 , wherein the controller is configured to communicate that there are an insufficient number of frequencies to the two or more communication devices wherein the controller is configured to instruct the two or more communication devices to share the insufficient number of frequencies on a time division basis.

16 . (canceled)

17 . A communication network as claimed in claims 9 , configured to allocate neighbouring communication devices the same length of time on each of the insufficient number of frequencies.

18 . A communication network as claimed in claims 9 , configured to allocate neighbouring communication devices different lengths of time on each of the insufficient number of frequencies.

19 . A communication network as claimed in claims 9 , configured such that each of the communication devices communicates with its at least one terminal via frames having the same duration, those communication devices being configured to, when sharing a frequency with a neighbouring communication device, commence transmitting each frame at a different time from the neighbouring communication device so that the frames of one communication device are offset from those of another.

20 . (canceled)

21 . (canceled)

22 . (canceled)

23 . A controller for determining a frequency hopping sequence for a communication device that is configured to communicate with at least one terminal via a frequency hopping sequence associated with its respective cell, the controller being configured to:

determine that there are an insufficient number of frequencies available to provide frequency hopping sequences for two or more communication devices in neighbouring cells that are sufficiently distinct from each other; and

instruct those two or more communication devices to share the insufficient number of frequencies between them on a time division basis.

24 . A controller as claimed in claim 17 , configured to determine that there are an insufficient number of frequencies available for a group of two or more neighbouring communication devices if the frequency hopping sequences derivable from those available frequencies require two or more neighbouring communication devices to use the same frequency for a length of time that is likely to lead to unacceptable packet loss.

25 . A controller as claimed in claim 17 , configured to allocate neighbouring communication devices the same length of time on each of the insufficient number of frequencies.

26 . A controller as claimed in claim 17 , configured to allocate neighbouring communication devices different lengths of time on each of the insufficient number of frequencies.

27 . (canceled)

28 . (canceled)

29 . (canceled)

30 . (canceled)