A method for performing uplink sounding reference signals transmissions in a wireless transmit/receive unit (WTRU), the method comprising: receiving a WTRU-specific configuration of WTRU-specific SRS subframes for performing SRS transmissions; receiving a trigger in a subframe from a base station to transmit a first SRS; selecting a first subframe after the subframe in which the trigger is received which is both a WTRU-specific subframe and at least four subframes after the subframe in which the trigger is received; characterized by: determining if a maximum power is exceeded in a symbol in the selected first subframe; on a condition that the maximum power is not exceeded in the symbol in the selected first subframe, transmitting the first SRS in the selected first subframe; on a condition that the maximum power is exceeded in the symbol in the selected first subframe and transmission of at least one channel type other than SRS at least partially overlaps in the symbol in the selected first subframe, dropping the first SRS from the selected first subframe and transmitting the at least one channel type other than SRS; and on a condition that the maximum power is exceeded in the symbol in the selected first subframe and transmission of at least one other SRS at least partially overlaps in the symbol in the selected first subframe, scaling transmission powers of the first SRS and the at least one other SRS equally to comply with the maximum power, and transmitting the first SRS in the selected first subframe in accordance with the scaled transmission powers, and transmitting the at least one other SRS in accordance with the scaled transmission powers. receiving a WTRU-specific configuration of WTRU-specific SRS subframes for performing SRS transmissions; receiving a trigger in a subframe from a base station to transmit a first SRS; selecting a first subframe after the subframe in which the trigger is received which is both a WTRU-specific subframe and at least four subframes after the subframe in which the trigger is received; characterized by: determining if a maximum power is exceeded in a symbol in the selected first subframe; on a condition that the maximum power is not exceeded in the symbol in the selected first subframe, transmitting the first SRS in the selected first subframe; on a condition that the maximum power is exceeded in the symbol in the selected first subframe and transmission of at least one channel type other than SRS at least partially overlaps in the symbol in the selected first subframe, dropping the first SRS from the selected first subframe and transmitting the at least one channel type other than SRS; and on a condition that the maximum power is exceeded in the symbol in the selected first subframe and transmission of at least one other SRS at least partially overlaps in the symbol in the selected first subframe, scaling transmission powers of the first SRS and the at least one other SRS equally to comply with the maximum power, and transmitting the first SRS in the selected first subframe in accordance with the scaled transmission powers, and transmitting the at least one other SRS in accordance with the scaled transmission powers. determining if a maximum power is exceeded in a symbol in the selected first subframe; on a condition that the maximum power is not exceeded in the symbol in the selected first subframe, transmitting the first SRS in the selected first subframe; on a condition that the maximum power is exceeded in the symbol in the selected first subframe and transmission of at least one channel type other than SRS at least partially overlaps in the symbol in the selected first subframe, dropping the first SRS from the selected first subframe and transmitting the at least one channel type other than SRS; and on a condition that the maximum power is exceeded in the symbol in the selected first subframe and transmission of at least one other SRS at least partially overlaps in the symbol in the selected first subframe, scaling transmission powers of the first SRS and the at least one other SRS equally to comply with the maximum power, and transmitting the first SRS in the selected first subframe in accordance with the scaled transmission powers, and transmitting the at least one other SRS in accordance with the scaled transmission powers.