Placement of idle periods

1. A telecommunications system comprising:

a plurality of transmitters capable of transmitting data in superframes, each superframe comprising a plurality of frames, and each frame comprising a plurality of slots;

the transmitters being arranged in groups, each group comprising a number of base stations, each group of base stations being assigned one or more slot numbers which are different from those of other groups and each of the transmitters of each group being assigned a different frame number, each transmitter being arranged to operate at reduced transmission power for a period commencing in the allocated slot or slots assigned to its group in the frame assigned to it.

2. A telecommunications system according to claim 1 , wherein each group comprises a set of nearby transmitters.

3. A telecommunications system according to claim 1 , wherein adjacent base stations within a group are assigned different frame numbers.

4. A telecommunications system according to claim 1 , wherein adjacent base stations belonging to different groups are assigned different frame numbers.

5. A telecommunications system according to claim 1 , wherein all the base stations within one group are assigned the same slot number or numbers.

6. A telecommunications system according to claim 1 , wherein each frame comprises 15 slots and geographically adjacent groups are assigned slots which are spaced apart by at least one slot period.

7. A telecommunications system according to claim 1 , each of the transmitters of each group being assigned more than one frame number.

8. A telecommunications system according to claim 1 , in which each superframe comprises 72 frames.

9. A telecommunications system according to claim 1 , wherein the transmitters operate asynchronously.

10. A telecommunications system according to claim 1 , wherein in order to operate at reduced transmission power during the slot or slots assigned to its group in the frame assigned to it, each transmitter is arranged to undergo an idle period.

11. A telecommunications system according to claim 1 , wherein each transmitter is arranged to operate at reduced transmission power for 0.667 ms during the slot or slots assigned to its group in the frame assigned to it.

12. A telecommunications system according to claim 1 , which is operable according to a W-CDMA system.

13. A telecommunications system according to claim 1 , wherein the said period is longer than one slot.

14. A telecommunications system according to claim 2 , wherein adjacent base stations within a group are assigned different frame numbers.

15. A telecommunications system according to claim 2 , wherein adjacent base stations belonging to different groups are assigned different frame numbers.

16. A telecommunications system according to claim 3 , wherein adjacent base stations belonging to different groups are assigned different frame numbers.

17. A telecommunications system according to claim 2 , wherein all the base stations within one group are assigned the same slot number or numbers.

18. A telecommunications system according to claim 3 , wherein all the base stations within one group are assigned the same slot number or numbers.

19. A telecommunications system according to claim 4 , wherein all the base stations within one group are assigned the same slot number or numbers.

20. A telecommunications system according to claim 2 , wherein each frame comprises 15 slots and geographically adjacent groups are assigned slots which are spaced apart by at least one slot period.

21. A telecommunications system according to claim 3 , wherein each frame comprises 15 slots and geographically adjacent groups are assigned slots which are spaced apart by at least one slot period.

22. A telecommunications system according to claim 4 , wherein each frame comprises 15 slots and geographically adjacent groups are assigned slots which are spaced apart by at least one slot period.

23. A telecommunications system according to claim 5 , wherein each frame comprises 15 slots and geographically adjacent groups are assigned slots which are spaced apart by at least one slot period.

24. A telecommunications system according to claim 2 , each of the transmitters of each group being assigned more than one frame number.

25. A telecommunications system according to claim 3 , each of the transmitters of each group being assigned more than one frame number.

26. A telecommunications system according to claim 4 , each of the transmitters of each group being assigned more than one frame number.

27. A telecommunications system according to claim 5 , each of the transmitters of each group being assigned more than one frame number.

28. A telecommunications system according to claim 6 , each of the transmitters of each group being assigned more than one frame number.

29. A telecommunications system according to claim 2 , in which each superframe comprises 72 frames.

30. A telecommunications system according to claim 3 , in which each superframe comprises 72 frames.

31. A telecommunications system according to claim 4 , in which each superframe comprises 72 frames.

32. A telecommunications system according to claim 5 , in which each superframe comprises 72 frames.

33. A telecommunications system according to claim 6 , in which each superframe comprises 72 frames.

34. A telecommunications system according to claim 7 , in which each superframe comprises 72 frames.

35. A telecommunications system according to claim 2 , wherein the transmitters operate asynchronously.

36. A telecommunications system according to claim 3 , wherein the transmitters operate asynchronously.

37. A telecommunications system according to claim 4 , wherein the transmitters operate asynchronously.

38. A telecommunications system according to claim 5 , wherein the transmitters operate asynchronously.

39. A telecommunications system according to claim 6 , wherein the transmitters operate asynchronously.

40. A telecommunications system according to claim 7 , wherein the transmitters operate asynchronously.

41. A telecommunications system according to claim 8 , wherein the transmitters operate asynchronously.

42. A telecommunications system according to claim 2 , wherein in order to operate at reduced transmission power during the slot or slots assigned to its group in the frame assigned to it, each transmitter is arranged to undergo an idle period.

43. A telecommunications system according to claim 3 , wherein in order to operate at reduced transmission power during the slot or slots assigned to its group in the frame assigned to it, each transmitter is arranged to undergo an idle period.

44. A telecommunications system according to claim 4 , wherein in order to operate at reduced transmission power during the slot or slots assigned to its group in the frame assigned to it, each transmitter is arranged to undergo an idle period.

45. A telecommunications system according to claim 5 , wherein in order to operate at reduced transmission power during the slot or slots assigned to its group in the frame assigned to it, each transmitter is arranged to undergo an idle period.

46. A telecommunications system according to claim 6 , wherein in order to operate at reduced transmission power during the slot or slots assigned to its group in the frame assigned to it, each transmitter is arranged to undergo an idle period.

47. A telecommunications system according to claim 7 , wherein in order to operate at reduced transmission power during the slot or slots assigned to its group in the frame assigned to it, each transmitter is arranged to undergo an idle period.

48. A telecommunications system according to claim 8 , wherein in order to operate at reduced transmission power during the slot or slots assigned to its group in the frame assigned to it, each transmitter is arranged to undergo an idle period.

49. A telecommunications system according to claim 9 , wherein in order to operate at reduced transmission power during the slot or slots assigned to its group in the frame assigned to it, each transmitter is arranged to undergo an idle period.

50. A telecommunications system according to claim 2 , wherein each transmitter is arranged to operate at reduced transmission power for 0.667 ms during the slot or slots assigned to its group in the frame assigned to it.

51. A telecommunications system according to claim 3 , wherein each transmitter is arranged to operate at reduced transmission power for 0.667 ms during the slot or slots assigned to its group in the frame assigned to it.

52. A telecommunications system according to claim 4 , wherein each transmitter is arranged to operate at reduced transmission power for 0.667 ms during the slot or slots assigned to its group in the frame assigned to it.

53. A telecommunications system according to claim 5 , wherein each transmitter is arranged to operate at reduced transmission power for 0.667 ms during the slot or slots assigned to its group in the frame assigned to it.

54. A telecommunications system according to claim 6 , wherein each transmitter is arranged to operate at reduced transmission power for 0.667 ms during the slot or slots assigned to its group in the frame assigned to it.

55. A telecommunications system according to claim 7 , wherein each transmitter is arranged to operate at reduced transmission power for 0.667 ms during the slot or slots assigned to its group in the frame assigned to it.

56. A telecommunications system according to claim 8 , wherein each transmitter is arranged to operate at reduced transmission power for 0.667 ms during the slot or slots assigned to its group in the frame assigned to it.

57. A telecommunications system according to claim 9 , wherein each transmitter is arranged to operate at reduced transmission power for 0.667 ms during the slot or slots assigned to its group in the frame assigned to it.

58. A telecommunications system according to claim 10 , wherein each transmitter is arranged to operate at reduced transmission power for 0.667 ms during the slot or slots assigned to its group in the frame assigned to it.

59. A telecommunications system according to claim 2 , which is operable according to a W-CDMA system.

60. A telecommunications system according to claim 3 , which is operable according to a W-CDMA system.

61. A telecommunications system according to claim 4 , which is operable according to a W-CDMA system.

62. A telecommunications system according to claim 5 , which is operable according to a W-CDMA system.

63. A telecommunications system according to claim 6 , which is operable according to a W-CDMA system.

64. A telecommunications system according to claim 7 , which is operable according to a W-CDMA system.

65. A telecommunications system according to claim 8 , which is operable according to a W-CDMA system.

66. A telecommunications system according to claim 9 , which is operable according to a W-CDMA system.

67. A telecommunications system according to claim 10 , which is operable according to a W-CDMA system.

68. A telecommunications system according to claim 11 , which is operable according to a W-CDMA system.

69. A telecommunications system according to claim 2 , wherein the said period is longer than one slot.

70. A telecommunications system according to claim 3 , wherein the said period is longer than one slot.

71. A telecommunications system according to claim 4 , wherein the said period is longer than one slot.

72. A telecommunications system according to claim 5 , wherein the said period is longer than one slot.

73. A telecommunications system according to claim 6 , wherein the said period is longer than one slot.

74. A telecommunications system according to claim 7 , wherein the said period is longer than one slot.

75. A telecommunications system according to claim 8 , wherein the said period is longer than one slot.

76. A telecommunications system according to claim 9 , wherein the said period is longer than one slot.

77. A telecommunications system according to claim 10 , wherein the said period is longer than one slot.

78. A telecommunications system according to claim 11 , wherein the said period is longer than one slot.

79. A telecommunications system according to claim 12 , wherein the said period is longer than one slot.