A method in a node is disclosed. The method comprises generating a tag for an associated data packet at a first layer, the generated tag indicating one or more parameters related to transmission of the associated data packet. The method comprises signaling the tag from the first layer to another layer. The method comprises mapping, at the another layer, the associated data packet to a logical channel based on the one or more parameters indicated by the tag, and selecting one or more resources for transmission of the associated data packet based on the mapping of the associated data packet to the logical channel.

Apparatuses and methods for physical random access channel (PRACH) preamble transmissions or receptions. A method of a UE includes receiving a physical downlink shared channel (PDSCH) that provides a system information block (SIB). The SIB includes an indication for (i) a first transmission configuration indication (TCI) state that provides a first set of quasi-collocation (QCL) properties and (ii) for a second TCI state that provides a second set of QCL properties. The method further includes transmitting a first PRACH according to the first TCI state and a second PRACH according to the second TCI state.

Aspects described herein relate to concurrently communicating with a base station over multiple frequency bands using a same first beam, and switching, according to beam switching criteria, from the first beam to a second beam during a time period, wherein the time period is based on a timing reference associated with a reference band.

There is provided generating, at a cell configured for a first air interface protocol, a reference signal based on a cell identifier for a second air interface protocol. At the cell configured for the first air interface protocol it is determined an air interface resource allocation for the first air interface protocol based on the cell identifier for the second air interface protocol. The cell configured for the first air interface protocol transmits the generated reference signal according to the determined air interface resource allocation.

Certain aspects of the present disclosure generally relate to wireless communications, and more specifically to sounding reference signal (SRS) transmissions in enhanced machine type communication (MTC). An example method generally includes determining one or more narrowband regions partitioned from wider system bandwidth for communicating with a base station, determining resources, within the one or more narrowband regions of a first subframe, for transmission of sounding reference signals (SRS) by the UE, deciding whether or not to transmit SRS on the determined resources of the first subframe, and transmitting or not transmitting the SRS on the determined resources of the first subframe based on the decision.

Techniques are described herein for performing channel estimation for both uplink and downlink channels. Additional reference signals may be allocated or assigned to various resource elements (REs) of a transmission time interval (TTI). The receiving device (e.g., a base station or a user equipment (UE)) may be configured to use the additional reference signals during channel estimation. The use of additional reference signals may improve the accuracy of the channel estimations. In downlink communications, a base station may allocate one or more channel state information reference signals (CSI-RSs) to a port of a UE. In uplink communications, a UE may transmit several sounding reference signals (SRSs) in a group.

A device implementing unified coordination of wireless communications over multiple physical layers may include a MAC module communicatively coupled to first and second physical layer modules that are each configured to communicate with another device over first and second physical wireless channels, respectively. The MAC module may be configured to provide data to the first physical layer module for transmission to the another device over the first physical wireless channel, where the first physical wireless channel is associated with a first link parameter. The MAC module may be further configured to facilitate initializing the second physical wireless channel based at least in part on the first link parameter of the first physical wireless channel, and after initialization of the second physical wireless channel, provide second data to the second physical layer module for transmission to the another device over the second physical wireless channel.

A user equipment (UE) is configured to vary a number of chains in uplink or downlink communications with a base station (BS). The UE includes a processor coupled to a transceiver. The processor is configured to: identify a full-chain beam for a downlink reception based on a beam sweeping; determine a number of activated chains for an uplink transmission; and determine a sub-chain uplink transmission beam.

An efficient return channel spectrum utilization technique for communication systems supporting adaptive spread spectrum. Requests for bandwidth allocation using a spread factor are analyzed to determine if there are any channels capable of supporting the spread factor. The request is acknowledged if at least one channel is capable of supporting the request. Adjacent channels required to accommodate the requested spread factor are reserved, and additional bandwidth requests are allocated on non-reserved channels.

Data transmission methods are provided. A data transmission method applied to a device supporting multi-link communication includes: determining channel status of at least two links in multiple links of the device; and determining whether to transmit first data on a first link of the at least two links based on the channel status of the at least two links.