What is claimed is:1. An apparatus, comprising:at least one processor configured to cause a user equipment (UE) to:receive a first physical downlink control channel (PDCCH) in a first partition of a Flexible Radio Access Technology (FRAT) used by a base station, wherein the first partition is associated with a first numerology of the FRAT, and wherein receiving the first PDCCH includes reception of scheduling information from the base station for a second partition associated with a second numerology of the FRAT,wherein respective subcarrier spacings of the first and second numerologies of the FRAT correspond to different integer multiples of 15 kHz, andwherein the FRAT comprises a unified frame structure for the first and second partitions, and wherein the unified frame structure includes:a frame comprising one or more subframes and corresponding to a frame duration of X milliseconds (ms); anda subframe comprising one or more slots and corresponding to a subframe duration of Y milliseconds (ms), wherein each slot of the one or more slots comprises one or more symbols, and wherein a slot duration and a symbol duration are different within one subframe of the one or more subframes for the first and second partitions.2. The apparatus of claim 1, wherein subframes of the one or more subframes between the first and second partitions are aligned in time.3. The apparatus of claim 1, wherein:the FRAT comprises a base subcarrier spacing and symbol duration, andat least one of the subcarrier spacing and symbol duration for each of the first and second partitions is respectively specified as an integer number of the base subcarrier spacing or symbol duration.4. The apparatus of claim 1, wherein the FRAT utilizes a plurality of radio access technologies (RATs) and wherein:the plurality of RATs comprises a common reference transmission time interval (TTI) duration, andthe second partition uses second sub carrier spacing and symbol duration different from the first partition, wherein a TTI boundary alignment exists between the first and second partitions, wherein the TTI is a smallest unit of time in which the UE is scheduled for uplink or downlink transmission, and wherein a first TTI for the first partition is different from a second TTI for the second partition.5. The apparatus of claim 1, wherein the FRAT utilizes a plurality of radio access technologies (RATs) and wherein:the LTE is a Machine-Type Communication (MTC) UE configured to operate in at least one of a low latency and low energy mode, anda first RAT of the plurality of RATs of the FRAT comprises a larger subcarrier spacing and shorter symbol duration when the UE operates in the low latency mode and comprises a smaller subcarrier spacing and longer symbol duration when the UE operates in the low energy mode.6. The apparatus of claim 1, wherein the FRAT utilizes a plurality of radio access technologies (RATs) and wherein:at least one of the plurality RATs of the FRAT comprises at least one of a plurality of sub-RATs and partitions, each of the at least one of the plurality of sub-RATs and partitions comprising an independent configurable numerology with flexible subcarrier spacing and symbol duration and associated with at least one of different temporal and frequency resource, andthe plurality of RATs and the at least one of the plurality of sub-RATs and partitions are combined using at least one of a Time-Division Multiplexing (TDM), Frequency-Division Multiplexing (FDM), Code-Division Multiplexing (CDM), and Spatial Division Multiplexing (SDM).7. The apparatus of claim 6, wherein the FRAT utilizes a plurality of radio access technologies (RATs) and wherein one of:the plurality of RATs and the at least one of the plurality of sub-RATs and partitions are combined using TDM, and numerologies, resource allocation and partition information in a time domain are at least one of predefined or configured by higher-layer signaling via Master Information Block (MIB), System Information Block (SIB) or UE-specific dedicated Radio Resource Control (RRC) signaling, orthe plurality of RATs and the at least one of the plurality of sub-RATs and partitions are combined using FDM, guard bands are inserted at an edge of frequency resources allocated for the plurality of RATs and the at least one of the plurality of sub-RATs and partitions, and at least one of numerologies and resource partition for the plurality of RATs and the at least one of the plurality of sub-RATs and partitions are at least one of predefined or configured by the higher-layer signaling.8. The apparatus of claim 1, wherein the FRAT utilizes a plurality of radio access technologies (RATs) and wherein:a Transmission Time interval (TTI) boundary between different RATs of the plurality of RATs of the FRAT is common, andthe plurality of RATs comprises a common reference TTI duration.9. The apparatus of claim 1, wherein the FRAT utilizes a plurality of radio access technologies (RATs) and wherein:a symbol structure of each of the first and second partitions comprises a cyclic prefix (CP), and the symbol structure of each of the plurality of RATs is independent of the symbol structure of other partitions.10. The apparatus of claim 1, wherein the at least one processor is further configured to cause the UE to:communicate using Orthogonal Frequency-Division Multiplexing (OFDM) for downlink communications and one of Single Carrier Frequency-Division Multiple Access (SC-FDMA) and OFDM for uplink communications, andcommunicate using at least one of unique word (UW)-OFDM (UW-OFDM) and UW Discrete Fourier transform-Spread-Orthogonal Frequency Division Multiplexing (UW-DFT-s-OFDM).11. A method, comprising:by a base station (BS):transmitting, to a user equipment (UE), a first physical downlink control channel (PDCCH) in a first partition of a Flexible Radio Access Technology (FRAT) used by the BS, wherein the first partition is associated with a first numerology of the FRAT, and wherein receiving the first PDCCH includes reception of scheduling information from the BS for a second partition associated with a second numerology of the FRAT,wherein respective subcarrier spacings of the first and second numerologies of the FRAT correspond to different integer multiples of 15 kHz, andwherein the FRAT comprises a unified frame structure for the first and second partitions, and wherein the unified frame structure includes:a frame comprising one or more subframes and corresponding to a frame duration of X milliseconds (ms); anda subframe comprising one or more slots and corresponding to a subframe duration of Y milliseconds (ms), wherein each slot of the one or more slots comprises one or more symbols, and wherein a slot duration and a symbol duration are different within one subframe of the one or more subframes for the first and second partitions.12. The method of claim 11, wherein subframes of the one or more subframes between the first and second partitions are aligned in time.13. The method of claim 11, wherein the FRAT utilizes a plurality of radio access technologies (RATs) and wherein the method further comprises:transmitting higher layer signaling indicating numerologies, resource allocation and partition information via Master Information Block (MIB) carried by a physical broadcast channel (PBCH), a System Information Block (SIB) or UE-specific dedicated Radio Resource Control (RRC) signaling in a same RAT of the FRAT to each of a plurality of UEs.14. The method of claim 11, wherein the FRAT utilizes a plurality of RATs and the method further comprises:transmitting numerologies, resource allocation and partition information via a dedicated carrier allocated for each of one or more RATs of the FRAT, whereina dedicated downlink synchronization signal and physical broadcast channel (PBCH) is able to be received on each of the one or more RATs.15. A user equipment (UE), comprising:transceiver circuitry; andone or more processors coupled to the transceiver circuitry and configured to cause the UE to:receive a first physical downlink control channel (PDCCH) in a first partition of a Flexible Radio Access Technology (FRAT) used by a base station, wherein the first partition is associated with a first numerology of the FRAT, and wherein receiving the first PDCCH includes reception of scheduling information from the base station for a second partition associated with a second numerology of the FRAT,wherein respective subcarrier spacings of the first and second numerologies of the FRAT correspond to different integer multiples of 15 kHz, wherein the FRAT comprises a unified frame structure for the first and second partitions, and wherein the unified frame structure includes:a frame comprising one or more subframes and corresponding to a frame duration of X milliseconds (ms); anda subframe comprising one or more slots and corresponding to a subframe duration of Y milliseconds (ms), wherein each slot of the one or more slots comprises one or more symbols, and wherein a slot duration and a symbol duration are different within one subframe of the one or more subframes for the first and second partitions.16. The UE of claim 15, wherein subframes of the one or more subframes between the first and second partitions are aligned in time.17. The UE of claim 15, wherein:the FRAT comprises a base subcarrier spacing and symbol duration, andat least one of the subcarrier spacing and symbol duration for each of the first and second partitions is respectively specified as an integer number of the base subcarrier spacing or symbol duration.18. The UE of claim 15, wherein the FRAT utilizes a plurality of radio access technologies (RATs) and wherein:the plurality of RATs comprise a common reference transmission time interval (TTI) duration, andthe second partition uses second sub carrier spacing and symbol duration different from the first partition, wherein a TTI boundary alignment exists between the first and second partitions, wherein the TTI is a smallest unit of time in which the UE is scheduled for uplink or downlink transmission, and wherein a first TTI for the first partition is different from a second TTI for the second partition.19. The UE of claim 15, wherein the FRAT utilizes a plurality of radio access technologies (RATs) and wherein:the UE is a Machine-Type Communication (MTC) UE configured to operate in at least one of a low latency and low energy mode, anda first RAT of the plurality of RATs of the FRAT comprises a larger subcarrier spacing and shorter symbol duration when the UE operates in the low latency mode and comprises a smaller subcarrier spacing and longer symbol duration when the UE operates in the low energy mode.20. The UE of claim 15, wherein the FRAT utilizes a plurality of radio access technologies (RATs) and wherein:at least one of the plurality RATs of the FRAT comprises at least one of a plurality of sub-RATs and partitions, each of the at least one of the plurality of sub-RATs and partitions comprising an independent configurable numerology with flexible subcarrier spacing and symbol duration and associated with at least one of different temporal and frequency resource, andthe plurality of RATs and the at least one of the plurality of sub-RATs and partitions are combined using at least one of a Time-Division Multiplexing (TDM), Frequency-Division Multiplexing (FDM), Code-Division Multiplexing (CDM), and Spatial Division Multiplexing (SDM).