A method for computing precoder matrix indicators, PMIs, in a wireless communication system, the wireless communication system including a base station, eNB, which is operable to communicate with one or more user equipments, UEs, and a set of multiple transmit antennas associated with the eNB that are partitioned into multiple transmit antenna subsets, wherein the UE(s) are operable to compute multiple PMIs for the respective multiple transmit antenna subsets and to report the multiple PMIs to the eNB for the eNB to use in precoding, the method comprising: computing a PMI for a given transmit antenna subset using other already-computed PMI(s) for other(s) of the transmit antenna subsets, wherein a channel H is the frequency response of the radio link between the transmit antennas associated with the eNB and the receiver antenna(s) associated with the UE(s), partitioning the array of transmit antennas into N transmit antenna subsets causes partitioning of the channel into N subchannels, and H n is the channel estimate of the n -th antenna subset, wherein the method further involves: A) initialising an initial composite channel matrix G 0 and initialising an initial composite precoder matrix V 0; B) performing the following for each of antenna subsets n = 1,..., N: (i) generating a new composite channel matrix G n using the previous composite channel matrix G n -1 and the channel estimate H n of the current antenna subset; (ii) generating composite precoder candidates V p for p = 1,..., N p using the previous composite precoder candidates V n-1 and the precoder (codeword) of the PMI codebook W p, p = 1,..., N p which is of size μ TX × RI, wherein N TX is the number of transmit antennas associated with the eNB, and Nμ TX = N TX, and wherein RI is a Rank Indicator; (iii) finding the PMI of the current antenna subset p n using the composite channel matrix G n and the composite precoder candidates V p; (iv) assigning a new composite precoder, wherein the initial composite channel matrix G 0 and the initial composite precoder matrix V 0 are both initialised as empty matrices. computing a PMI for a given transmit antenna subset using other already-computed PMI(s) for other(s) of the transmit antenna subsets, wherein a channel H is the frequency response of the radio link between the transmit antennas associated with the eNB and the receiver antenna(s) associated with the UE(s), partitioning the array of transmit antennas into N transmit antenna subsets causes partitioning of the channel into N subchannels, and H n is the channel estimate of the n -th antenna subset, wherein the method further involves: A) initialising an initial composite channel matrix G 0 and initialising an initial composite precoder matrix V 0; B) performing the following for each of antenna subsets n = 1,..., N: (i) generating a new composite channel matrix G n using the previous composite channel matrix G n -1 and the channel estimate H n of the current antenna subset; (ii) generating composite precoder candidates V p for p = 1,..., N p using the previous composite precoder candidates V n-1 and the precoder (codeword) of the PMI codebook W p, p = 1,..., N p which is of size μ TX × RI, wherein N TX is the number of transmit antennas associated with the eNB, and Nμ TX = N TX, and wherein RI is a Rank Indicator; (iii) finding the PMI of the current antenna subset p n using the composite channel matrix G n and the composite precoder candidates V p; (iv) assigning a new composite precoder, A) initialising an initial composite channel matrix G 0 and initialising an initial composite precoder matrix V 0; B) performing the following for each of antenna subsets n = 1,..., N: (i) generating a new composite channel matrix G n using the previous composite channel matrix G n -1 and the channel estimate H n of the current antenna subset; (ii) generating composite precoder candidates V p for p = 1,..., N p using the previous composite precoder candidates V n-1 and the precoder (codeword) of the PMI codebook W p, p = 1,..., N p which is of size μ TX × RI, wherein N TX is the number of transmit antennas associated with the eNB, and Nμ TX = N TX, and wherein RI is a Rank Indicator; (iii) finding the PMI of the current antenna subset p n using the composite channel matrix G n and the composite precoder candidates V p; (iv) assigning a new composite precoder, (i) generating a new composite channel matrix G n using the previous composite channel matrix G n -1 and the channel estimate H n of the current antenna subset; (ii) generating composite precoder candidates V p for p = 1,..., N p using the previous composite precoder candidates V n-1 and the precoder (codeword) of the PMI codebook W p, p = 1,..., N p which is of size μ TX × RI, wherein N TX is the number of transmit antennas associated with the eNB, and Nμ TX = N TX, and wherein RI is a Rank Indicator; (iii) finding the PMI of the current antenna subset p n using the composite channel matrix G n and the composite precoder candidates V p; (iv) assigning a new composite precoder, wherein the initial composite channel matrix G 0 and the initial composite precoder matrix V 0 are both initialised as empty matrices.