Time-sharing of sounding resources

1. A method for allocating sounding resources in a wireless system having plural sounding resources comprising the steps of:

time-sharing one sounding resource across plural user equipment for different sub-frames;

wherein said plural user equipment require different sounding periods which are periodic and non-changing in time; and

wherein said time-sharing allocations user equipment to sub-frames in differing periods.

2. A method for allocating sounding resources in a wireless system having plural sounding resources comprising the steps of:

time-sharing one sounding resource across plural user equipment for different sub-frames;

wherein said plural user equipment require different sounding periods which are periodic and changing in time; and

wherein said step of time-sharing one sounding resource includes

recursively forming a sounding resource sharing tree of possible allocations of said one sounding resource to plural user equipment,

selecting a vertex of the sounding resource sharing tree, and

allocating sounding resources dependent upon said selected vertex.

3. The method of claim 2 , wherein:

said step of time-sharing one sounding resource further includes

forming a valid sharing configuration of all vertices of said sounding resource tree, and

said step of selecting a vertex of the sounding resource sharing tree includes selecting a vertex within the valid sharing configuration.

4. The method of claim 3 , wherein:

said step of forming a valid sharing configuration includes

initializing all vertices as available, and

for every user equipment from a user equipment having the shortest sounding period to a user equipment having a longest sounding period

finding an available vertex for a current user equipment,

allocating the available vertex for the current user equipment, and

removing from availability said allocated available vertex and all descendent vertices.

5. The method of time-sharing of a sounding reference signal resource between a group of mobile user equipments, comprising the steps of:

signaling a sounding reference signal resource identifier to a first user equipment;

signaling the sounding reference signal resource identifier to a second user equipment;

signaling a first sounding reference signal periodicity to the first user equipment;

signaling a first sounding reference signal offset to the first user equipment;

signaling a second sounding reference signal offset to the second user equipment different than the first sounding signal offset;

signaling a second sounding reference signal periodicity to the second user equipment, the second sounding reference signal periodicity is an integral multiple of the first sounding reference signal periodicity measured with respect to a time reference shared between user equipments in the group of user equipments.

6. The method of claim 5 , wherein:

said steps of signaling the first sounding reference signal periodicity to the first user equipment and signaling the second sounding reference signal periodicity to the second user equipment each select a periodicity from the set consisting of 2 ms, 5 ms, 10 ms, 20 ms, 40 ms, 80 ms, 160 ms and 320 ms.

7. The method of claim 5 , wherein:

said steps of signaling a sounding reference signal resource identifier comprises signaling a group of parameters group N by selecting a reference sequence from a reference sequence identifier map h(t, N), where t is a common time identifier and N is a group of shared parameters.

8. The method of claim 7 , wherein:

said reference sequence identifier map h(t, N) identifies a modified Zadoff-Chu (ZC) sequence.

9. The method of claim 7 , wherein:

said steps of signaling a sounding reference signal identifier comprises signaling a group of parameters group L by selecting a spectrum resource from a spectrum identifier map f(t, N), where t is a common time identifier and N is a group of shared parameters.

10. The method of claim 9 , wherein:

said spectrum identifier map f(t, L) maps to a fixed spectrum.

11. A method for allocation of an offset and a periodicity associated with a sounding reference signal resource identifier to a user equipment comprising the steps of:

signaling an offset y from a set X to a user equipment, where X is a finite set of available offsets associated with said sounding reference signal resource;

signaling a periodicity s to the user equipment; and

updating the set X by removing a group of at least one offset from the set X, each offset of the group having the form y+k*s where k is an integer.

12. The method of claim 11 , wherein:

y is the smallest offset in the set X.

13. The method of claim 11 , wherein:

y is the largest offset in the set X.

14. The method of claim 11 , wherein:

y is the earliest available offset in the set X.

15. A method for de-allocation of an offset associated with an sounding reference signal resource; comprising

updating a set X by inserting a group of at least one offset into the set X, each offset of the group having the form y+k*s, where: X is a set of available offsets associated with the sounding reference signal resource identifier; y is the sounding reference signal offset previously allocated to a user equipment; s is the periodicity previously allocated to the user equipment; and k is an integer.

16. The method of claim 15 , further comprising the steps of:

maintaining a set of allocated periodicities s(K) for each sounding reference signal resource; and

allocating the sounding reference signal resource to additional user equipment with s(N+1) only if the sum of reciprocals of s(K) is less than or equal to 1.

17. The method of claim 15 , wherein:

s is selected from a set consisting of least two numbers; and

for any pair of numbers in the set s(K) the larger number is an integral multiple of the smaller one.

18. The method of claim 15 , wherein:

the set s(K) is 5 ms, 10 ms, 20 ms, 40 ms, 80 ms, 160 ms and 320 ms.

19. The method of claim 15 , wherein:

the set s(K) is 2 ms, 10 ms, 20 ms, 40 ms, 80 ms, 160 ms and 320 ms.