TECHNICAL FIELD

This disclosure pertains to wireless communication technology, in particular in the context of 5G telecommunication, e.g. New Radio (NR) or LTE Evolution.

BACKGROUND

Next to carrier aggregation, in which a plurality of carriers are aggregated or joined together in frequency domain, current development of wireless communication technology also goes into the direction of aggregating transmission timing structures in time domain.

SUMMARY

It is an object of this disclosure to provide approaches allowing efficient signaling in the context of slot aggregation as a form of transmission timing structure aggregation, in particular signaling with limited overhead.

The approaches described herein are particularly useful in the context of NR Radio Access Technology/Networks (NR RAT/RAN). Thus, a network node may in particular a gNB (or eNB in some cases).

Accordingly, there is disclosed a method of operating a network node in a Radio Access Network. The method comprises transmitting a downlink control information message, the downlink control information message comprising a slot allocation indication and a symbol allocation indication. The slot allocation indication indicates a slot aggregation comprising a plurality of slots being allocated for communication to at least one user equipment, wherein each slot comprises a plurality of symbols. The symbol allocation indication indicates allocation of symbols to at least one channel according to an allocation pattern for two or more of the plurality of slots.

Also, there is disclosed a network node for a Radio Access Network. The network node is adapted for transmitting a downlink control information message, the downlink control information message comprising a slot allocation indication and a symbol allocation indication. The slot allocation indication indicates a slot aggregation comprising a plurality of slots being allocated for communication to at least one user equipment, wherein each slot comprises a plurality of symbols. The symbol allocation indication indicates allocation of symbols to at least one channel according to an allocation pattern for two or more of the plurality of slots. The network node may comprise, and/or be adapted for utilizing, processing circuitry and/or radio circuitry, in particular a transmitter, for such transmitting. Alternatively, or additionally, the network node may comprise a corresponding transmitting module.

A method of operating a user equipment, UE, in a Radio Access Network may be considered. The method comprises communicating utilizing a slot aggregation based on a received downlink control information message, the downlink control information message comprising a slot allocation indication and a symbol allocation indication. The slot allocation indication indicates a slot aggregation comprising a plurality of slots being allocated for communication to the user equipment, wherein each slot comprises a plurality of symbols. The symbol allocation indication indicates allocation of symbols to at least one channel according to an allocation pattern for two or more of the plurality of slots.

In addition, a user equipment for a Radio Access Network is described. The user equipment is adapted for communicating utilizing a slot aggregation based on a received downlink control information message, the downlink control information message comprising a slot allocation indication and a symbol allocation indication. The slot allocation indication indicates a slot aggregation comprising a plurality of slots being allocated for communication to the user equipment, wherein each slot comprises a plurality of symbols. The symbol allocation indication indicates allocation of symbols to at least one channel according to an allocation pattern for two or more of the plurality of slots. The UE may comprise, and/or be adapted for utilizing, processing circuitry and/or radio circuitry, in particular a transmitter and/or receiver and/or receiver, for such communicating. Alternatively, or additionally, the UE may comprise a corresponding communicating module.

The slot allocation indication may comprise a bit pattern indicating the number of slots being aggregated and/or a slot location indication, the slot location indication indicating the location of a reference slot of the slot aggregation. There may be a unique or 1-1 mapping of slot aggregation length (number of slots in the aggregation) and/or the reference slot location to the bit pattern, e.g. according to a table, which may be predefined or configured.

A slot location may generally pertain to an arrangement in time domain and/or relative to a timing or timing structure. A slot location may indicate where in time a slot is located, e.g. by providing an absolute slot number or a slot number relative to another slot, e.g. a slot in which the downlink control information is received. The reference slot may be a slot of the slot aggregation, based on whose location the location of the slot aggregation may be determined or be fixed. The reference slot may in particular be the first slot of the slot aggregation, or the last slot of the slot aggregation. Based on the reference slot and the number of slots in the slot aggregation the time interval covered by the slot aggregation may be defined or determined.

A bit pattern may generally comprise one or more bits, in particular 2, 3 or 4 bits. It may generally be considered that the symbol allocation indication comprises of 3 bits, which may be mapped to allocation patterns, e.g. represented by starting symbol and/or ending symbol and/or length. The slot allocation indication may comprise of 3 bits, which may be mapped to reference slot locations and/or number of slots in an aggregation.

The symbol allocation indication may comprise a bit pattern, the bit pattern indicating the allocation pattern and/or the channel or channels the symbols are allocated to.

The (allocation) pattern may indicate or represent a starting symbol and/or ending symbol and/or number of symbols allocated to a specific channel.

In some variants, the allocation pattern may indicate or include a guard period between symbols of the allocation pattern allocated to a downlink channel and symbols of the pattern allocated to an uplink channel, and/or vice versa. A guard period may comprise and/or extend over one or more symbol time lengths. A guard period may be associated to no transmission or reception being scheduled.

The downlink control information message may comprise one or more deviation indications, a deviation indication generally indicating a deviation from the pattern for one or more slots. Alternatively, or additionally, the downlink control information message may indicate frequency resource allocation, e.g. subcarrier range, for one or more, in particular for all, slots of the slot aggregation. The frequency resource allocation may be indicated by a frequency allocation indication, and/or may be the same for more than one, in particular for all, slots of the slot aggregate. In the latter case, only one indication may be needed and/or provided. Also alternatively, or additionally, the downlink control information message may comprise a frequency hopping indication, which may indicate a frequency hopping scheme for the allocated channels e.g. between different slots of the slot aggregation, and/or within individual slots.

Alternatively, or additionally, there may be considered that the network node is adapted for, and/or the method of operating the network node comprises, transmitting a second message, e.g. a downlink control information message and/or other configuration message (message comprising configuration data), the second message comprising one or more deviation indications. Communicating utilizing the slot aggregation may be based also on the second message. Accordingly, greater flexibility for deviations from the pattern may be provided, while limiting the overhead of the downlink control information message. The second message, and/or the downlink control message, may be valid for the duration of the slot aggregation (dynamic), or valid for a plurality of such durations (semi-static), e.g. provided in RRC signaling.

Allocating a slot aggregation for communication may pertain to allocating resources associated to the slots of the aggregation for communication. The resources may be time-frequency resources associated to, and/or arranged or located within, the time interval defined by the slot aggregations, respectively associated to the symbol time intervals of the symbols of the slot aggregation, which comprise the symbols of the slots of the aggregation. Allocating may generally comprise indicating, e.g. to a user equipment, which symbols and/or resources to use for which king of communication, e.g. transmitting or receiving, and/or on which channel.

An allocation pattern may generally indicate at least one channel that is allocated to one or more symbols (or vice versa, as the allocation may represent a unique or 1-1 mapping). However, in some cases, there may be allocated more than one channel to a symbol, e.g. a control and a data channel. In this case, the channels may be multiplexed, in particular in frequency. Such channels may represent the same direction of communication, e.g. transmitting or receiving. The allocation pattern may indicate the frequency resource/s allocated to the channel/s, or such may be implicitly indicated, e.g. according to a configuration or predefinition or rule. An allocation pattern may allocate symbols for two or more slots such that the pattern of symbols repeats for each slot. For example, the same channel/s may be allocated to symbols (respectively the associated resources) with the same number inside each slot. It may be assumed that the symbols in a slot may be numbered by successive integers, e.g. from 0 to 6 or 0 to 13, or 1 to 7 or 1 to 14, depending on the total number of symbols in a slot. The numbering may be analogous between slots with the same number of symbols. Successively numbered symbols may be neighboring to each other in time domain, with a common time border.

The downlink control information message may allocate and/or schedule the slot aggregation, such that resources of the slot aggregation are allocated for communication.

A slot may comprise a plurality of symbols, in particular 7 or 14 symbols. However, a slot may be implemented as a mini-slot with fewer symbols than a full slot in some variants. It may be considered that the slots of the slot aggregation have the same number of symbols, and/or that the slots of the slot aggregation have the same durations (extension in time domain). However, there may be considered variants in which different slot durations, or slots with different number of symbols, are aggregated into a slot aggregation. In this context it may be considered that an allocation pattern only pertains to slots having the same duration or the same number of symbols, to limited signaling overhead. A slot aggregation may comprise two or more slots, in particular 2, 3 or 4, or an even number of slots.

Allocating symbols to at least one channel may comprise indicating one or more channels on which to communicate. A channel may be an uplink or downlink or sidelink channel. In particular, a channel may be a physical channel. Examples of channels that may be allocated comprise PUCCH, PUSCH, PDSCH, PDCCH. A channel may be a control channel, e.g. PUCCH or PDCCH, or a data channel, e.g. PUSCH or PDSCH. A control channel, in particular a downlink control channel, may be arranged or allocated in a control region, which may cover one or more symbols of a slot of the slot aggregation, e.g. at the beginning of the slot. It may be considered that an uplink control region is allocated an uplink control channel. An allocation pattern may for example be continuous in time domain and/or frequency domain for a time interval covering one or more symbols and/or a frequency interval covering one or more subcarriers. Such a pattern may appear rectangular in a time/frequency diagram representation. The symbol allocation indication may indicate the location and/or extension of such a pattern in time domain, e.g. by indicating a starting and ending symbol, and/or a starting or ending (also referred to as stop) symbol and a duration (e.g., in number of symbols) or length. A symbol may in particular be an OFDM (Orthogonal Frequency Division Multiplexing) symbol, e.g. in NR downlink, or a OFDMA (Orthogonal Frequency Division Multiple Access) or SC-FDMA (Single Carrier Frequency Division Multiple Access) symbol in uplink or sidelink.

Communicating utilizing a slot aggregation may comprise transmitting and/or receiving on the channels allocated according to the allocation pattern.

The slots of a slot aggregation may be arranged in time such they form a continuous time interval covered by the symbols time intervals of the symbols of the slots.

Generally, to a symbol there may be associated a symbol time interval, and a frequency range, e.g. a number of subcarrier. For ease of reference, it may be referred to a symbol even if only the time domain extension (symbol time interval) is referred to. In the context of resources or allocation, an extension of a symbol into the frequency domain may be assumed. The symbols or slots of a slot aggregation may comprise the same extension in frequency domain, e.g. pertain to the same subcarriers or carriers. The extension in frequency domain may be continuous.

An allocation pattern pertaining to a plurality of slots may be considered to comprise an allocation (sub-)pattern valid for one slot, which is repeated in the other slots of the plurality of slots.

It should be noted that in some variants, the slot allocation indication and the symbol allocation indication pertain to allocation in time domain, pertaining to symbols or slots, respectively their associated time intervals. Frequency allocation may be implicitly indicated, or explicitly with a corresponding frequency allocation indication in the downlink control information message.

A downlink control information message may comprise downlink control information, in particular pertaining to scheduling and/or allocation, for uplink and/or downlink and/or sidelink communication.

A program product comprising instructions causing processing circuitry to control and/or perform any one of the methods described herein is also disclosed.

Moreover, there is disclosed a carrier medium arrangement carrying and/or storing a program product as disclosed herein.

A transmission timing structure may generally comprise a (e.g., pre-defined and/or configured) number of symbols or symbol time intervals. A slot may be considered a representation or implementation of a transmission timing structure, and the terms may be interchanged in the context of this disclosure. A transmission timing structure may define a time interval. To a transmission timing structure and/or slot there may associated frequency resources, such that a slot may represent time/frequency resources, based on a time interval of the slot. A slot aggregation may comprise a plurality of slots scheduled with a single downlink control information message.

