A wireless transmit/receive unit, WTRU, comprising: a processor; and a transceiver operatively coupled to the processor; wherein the transceiver is configured to receive, from a base station that uses a first radio access technology, RAT, configuration information, wherein the first RAT is a Long-Term Evolution, LTE, RAT, wherein the configuration information includes beam assignment information for acquiring a plurality of beams of at least one candidate millimeter wave, mmW, base station, mB, that uses a second RAT and timing information for measuring a signal strength of each of the plurality of beams, the timing information including a start time specified in terms of an offset, wherein the offset is a number of mmW TTIs that accounts for a path delay between the timing of a candidate mB beacon transmission and a frame and subframe associated with the first RAT used by the base station; wherein transceiver and the processor are configured to start to measure, at the start time based on the indicated timing information, a signal strength of each of the plurality of beams to detect one or more best mB and beam combinations; wherein the transceiver is configured to transmit, to the base station that uses the first RAT, a measurement report that indicates the one or more highest measured signal strengths and associated mB identities and beam indices, wherein the one or more highest measured signal strengths include at least one measured signal strength of a beam of a candidate mB; and wherein the transceiver is configured to receive, on an assigned mmW, link, using at least one of the plurality of beams, user data transmissions from the respective candidate mB. a processor; and a transceiver operatively coupled to the processor; wherein the transceiver is configured to receive, from a base station that uses a first radio access technology, RAT, configuration information, wherein the first RAT is a Long-Term Evolution, LTE, RAT, wherein the configuration information includes beam assignment information for acquiring a plurality of beams of at least one candidate millimeter wave, mmW, base station, mB, that uses a second RAT and timing information for measuring a signal strength of each of the plurality of beams, the timing information including a start time specified in terms of an offset, wherein the offset is a number of mmW TTIs that accounts for a path delay between the timing of a candidate mB beacon transmission and a frame and subframe associated with the first RAT used by the base station; wherein transceiver and the processor are configured to start to measure, at the start time based on the indicated timing information, a signal strength of each of the plurality of beams to detect one or more best mB and beam combinations; wherein the transceiver is configured to transmit, to the base station that uses the first RAT, a measurement report that indicates the one or more highest measured signal strengths and associated mB identities and beam indices, wherein the one or more highest measured signal strengths include at least one measured signal strength of a beam of a candidate mB; and wherein the transceiver is configured to receive, on an assigned mmW, link, using at least one of the plurality of beams, user data transmissions from the respective candidate mB.