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WE CLAIM:
1. A method of configuring a timing advance group for a secondary cell, in a
base station, the method comprising the steps of:
II1. triggering (S1) a random access procedure of a user equipment over the
secondary cell;
II2. obtaining (S1) a timing advance value of the user equipment over the
secondary cell according to a result of the random access procedure of the user
equipment over the secondary cell; and
II3. determining a final timing advance group to which the secondary cell
belongs according to the timing advance value,
wherein, after the step II3, the method further comprises the step of:
II4. providing the user equipment with an identifier of the final timing
advance group,
wherein before the step II1, the method further comprises the steps of:
I. transmitting an initial timing advance group identifier to the
secondary cell of the user equipment via a radio link control message or a
media access control protocol data unit; and
II. determining whether the timing advance group identifier is valid
for the secondary cell; and
If it is invalid for the secondary cell, then performing the step II1 and
the step II2; and
the step II3 further comprises: comparing (S2) obtained timing
advance value with timing advance values pre-stored in the base station; and
II31. taking a timing advance group corresponding to the prestored timing advance value as the final timing advance group of the
secondary cell, when a difference between the obtained timing
advance value and any one of timing advance values pre-stored in the
base station is within a predetermined range; or
II32. taking a timing advance group corresponding to the
obtained timing advance value as the final timing advance group of 15
the secondary cell, when a difference between the obtained timing
advance value and any one of the timing advance values pre-stored in
the base station exceeds the predetermined range.
2. The method according to claim 1, wherein the step II4 transmits by any one
of the followings:
- including the identifier of the final timing advance group in a message 2 for
transmission to the user equipment, for the user equipment with a contention-free
random access; and
- including the identifier of the final timing advance group in a message 4 for
transmission to the user equipment, for the user equipment with a contentionbased random access.