An interference randomization method in a user equipment, UE, comprising: encoding a set of control information bits comprising ACK/NACK bits to generate encoded control information bits; scrambling the encoded control information bits to generate scrambled control information bits; modulating the scrambled control information bits to generate modulated symbols; determining a physical uplink control channel, PUCCH, ACK/NACK resource index; determining a first orthogonal sequence index, a second orthogonal sequence index, and a cyclic shift for a base sequence to generate a demodulation reference signal, DMRS, wherein each of the first orthogonal sequence index, the second orthogonal sequence index, and the cyclic shift is determined based on the PUCCH ACK/NACK resource index; spreading the modulated symbols block-wise using a first orthogonal sequence indicated by the first orthogonal sequence index and a second orthogonal sequence indicated by the second orthogonal sequence index, wherein the first orthogonal sequence indicated by the first orthogonal sequence index is the orthogonal sequence associated with a first slot of a subframe and the second orthogonal sequence indicated by the second orthogonal sequence index is the orthogonal sequence associated with a second slot of the subframe; applying the cyclic shift to the base sequence to generate the DMRS; and transmitting the DMRS and the block-wise spread modulated symbols on a PUCCH. encoding a set of control information bits comprising ACK/NACK bits to generate encoded control information bits; scrambling the encoded control information bits to generate scrambled control information bits; modulating the scrambled control information bits to generate modulated symbols; determining a physical uplink control channel, PUCCH, ACK/NACK resource index; determining a first orthogonal sequence index, a second orthogonal sequence index, and a cyclic shift for a base sequence to generate a demodulation reference signal, DMRS, wherein each of the first orthogonal sequence index, the second orthogonal sequence index, and the cyclic shift is determined based on the PUCCH ACK/NACK resource index; determining a physical uplink control channel, PUCCH, ACK/NACK resource index; determining a first orthogonal sequence index, a second orthogonal sequence index, and a cyclic shift for a base sequence to generate a demodulation reference signal, DMRS, wherein each of the first orthogonal sequence index, the second orthogonal sequence index, and the cyclic shift is determined based on the PUCCH ACK/NACK resource index; spreading the modulated symbols block-wise using a first orthogonal sequence indicated by the first orthogonal sequence index and a second orthogonal sequence indicated by the second orthogonal sequence index, wherein the first orthogonal sequence indicated by the first orthogonal sequence index is the orthogonal sequence associated with a first slot of a subframe and the second orthogonal sequence indicated by the second orthogonal sequence index is the orthogonal sequence associated with a second slot of the subframe; applying the cyclic shift to the base sequence to generate the DMRS; and transmitting the DMRS and the block-wise spread modulated symbols on a PUCCH.