CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Submission Under 35 U.S.C. § 371 for U.S. National Stage Patent Application of International Application Number: PCT/SE2017/050449, filed May 5, 2019 entitled “SIGNALING FOR RADIO ACCESS NETWORKS,” the entirety of which is incorporated herein by reference.

TECHNICAL FIELD

The present disclosure pertains to wireless communication technology, in particular in the context of control signaling.

BACKGROUND

Modern communication technology, in particular technology of the 5th Generation (5G) aims at servicing a large variety of use cases and applications, and provides a high level of flexibility for communication and signaling. However, flexibility usually introduces significant signaling overhead.

SUMMARY

It is an object of the present disclosure to provide approaches allowing flexibility with limited overhead, in particular in the context of control signaling. The approaches described herein are particularly suitable for a Radio Access Network (RAN), in particular a 5G RAN like New Radio (NR) or LTE Evolution according to 3GPP (3rd Generation Partnership Project, a telecommunications standardization organization).

There is disclosed a method of operating a user equipment in a Radio Access Network. The method comprises transmitting signaling in a first transmission timing structure starting at a starting symbol, the starting symbol being determined based on a received transmission timing structure indication. The transmission timing structure indication indicates the first transmission timing structure.

Moreover, alternatively, or additionally, a (second) method of operating a user equipment in a Radio Access Network is described. The method comprises determining a border symbol indicating a border of a transmission scheduled in a first transmission timing structure. The border symbol is determined based on a received transmission timing structure indication, the transmission timing structure indication indicating the first transmission timing structure. The method also comprises transmitting or receiving signaling based on the determined border symbol.

A user equipment for a Radio Access Network may be considered. The user equipment is adapted for transmitting signaling in a first transmission timing structure starting at a starting symbol. The starting symbol is determined based on a received transmission timing structure indication, the transmission timing structure indication indicating the first transmission timing structure. The user equipment may comprise, and/or be adapted for utilising, processing circuitry and/or radio circuitry, e.g. a transmitter and/or transceiver, for such transmitting. Alternatively, or additionally, the user equipment may comprise a transmitting module for such transmitting.

Alternatively, or additionally, a (second) user equipment for a Radio Access Network may be considered. The user equipment is adapted for determining a border symbol indicating a border of a transmission scheduled in a first transmission timing structure, the border symbol being determined based on a received transmission timing structure indication. The transmission timing structure indication indicates the first transmission timing structure. The user equipment is further adapted for transmitting or receiving signaling based on the determined border symbol. The user equipment may comprise, and/or be adapted for utilising, processing circuitry and/or radio circuitry, e.g. a transmitter and/or transceiver and/or receiver, for such determining and/or transmitting and/or receiving. Alternatively, or additionally, the user equipment may comprise a determining module for such determining, and/or a transmitting module for such transmitting, and/or a receiving module for such receiving.

Generally, a user equipment may comprise, and/or be adapted for utilising, processing circuitry and/or radio circuitry, e.g. a receiver or transceiver, for receiving the transmission timing structure indication. The circuitry/ies may be the same as mentioned above, used for more than one functionality. The indication may be included in signaling, e.g. control signaling, which may be received signaling. Received signaling may generally be downlink signaling, or in some cases sidelink signaling.

Moreover, a method of operating a radio node in a Radio Access Network is discussed. The method comprises transmitting control signaling to a user equipment, the control signaling comprising a transmission timing structure indication. The method also comprises receiving, from the user equipment, signaling transmitted in a first transmission timing structure starting at a starting symbol based on a transmission timing structure indication, the transmission timing structure indication indicating the first transmission timing structure.

A radio node for a Radio Access Network is also described. The radio node is adapted for transmitting control signaling to a user equipment, the control signaling comprising a transmission timing structure indication. The radio node is also adapted for receiving, from the user equipment, signaling transmitted in a first transmission timing structure starting at a starting symbol based on a transmission timing structure indication, the transmission timing structure indication indicating the first transmission timing structure. The radio node may comprise, and/or be adapted for utilising, processing circuitry and/or radio circuitry, in particular a transmitter and/or transceiver and/or receiver, for such transmitting and/or receiving. Alternatively, or additionally, the radio node may comprise a transmitting module for such transmitting and/or a receiving module for such receiving.

Transmitting the control signaling comprising the indication may be considered configuring the user equipment. Receiving signaling starting at the starting symbol may comprise expecting the transmission based on the starting symbol, e.g. considering signaling traveling time.

The control signaling may be downlink control signaling or in same case sidelink control signaling, e.g. on an associated control channel. Receiving signaling based on a border symbol, in particular an ending symbol, may comprise expecting and/or interpreting the signaling to end at the symbol, and/or switching circuitry from receiving to transmitting.

According to the approaches described herein, a border symbol of scheduled transmission, e.g. a starting symbol or ending symbol, may be determined based on a transmission timing structure indication. No additional overhead is required to specifically indicate the border symbol. This may be particularly useful in the context of the border symbol being in the same transmission timing structure in which the indication is received. The approaches in particular allow to take into account processing time required before transmitting may be performed, e.g. by determining a starting symbol to be late enough in the timing structure to allow for processing, or by ending the reception in the timing structure early enough. The border symbol may be determined differ for differing timing distances between the transmission timing structure of reception of the transmission timing structure indication and the first transmission timing structure.

In some variants, the transmission timing structure indication may schedule the indicated transmission timing structure, e.g. for receiving signaling, and/or for transmitting signaling. The transmitting signaling may be scheduled after, and/or in response to, signaling scheduled for receiving.

The transmission timing structure indication may be at the beginning of a transmission timing structure it is transmitted in. It may generally be considered that the transmission timing structure indication is a slot indication, indicating a slot (or mini-slot) for transmitting or receiving. Accordingly, the first transmission timing structure may be such a slot or mini-slot.

Generally, if the first transmission timing structure is the transmission timing structure of reception of the transmission timing structure indication, the border symbol, in particular a starting symbol and/or ending symbol may be determined considering a processing timing. A processing timing may generally be based on capabilities of the radio node or user equipment, which may be signaled to the network or network node, or generally to the radio node transmitting the transmission timing structure indication. The processing timing may be determined based on a signaling travelling time, e.g. a timing advance value, and/or processing time for packaging and/or modulating and/or encoding data for transmission. If the data is to be transmitted in response to received signaling, the processing time may be considered to include time for decoding and/or demodulating and/or evaluation received signaling, e.g. to determine associated acknowledgment information, and/or for switching circuitry form receiving to transmitting. Processing timing may be considered by shifting an ending symbol to an earlier symbol, or a starting symbol to a later symbol (corresponding to a smaller symbol number or a larger symbol number, e.g. in one transmission timing structure). Processing timing may be specific to a radio nod, e.g. like a UE or terminal, and/or may be signaled or indicated or configured to the radio node, e.g. by the network or network node. The processing timing may be represented by a symbol number or shift. Different UEs or terminals may have associated to them different processing timings. Processing timing may be indicated and/or configured semi-statically or statically, e.g. by RRC layer signaling. Such processing timing may disregard signal traveling time, which may be configured more dynamically.

A starting symbol for signaling in response to received signaling (e.g., acknowledgement signaling) may be later in time than a starting symbol for signaling not in response, e.g. data signaling, which may in particular be PUSCH signaling. This may be in particular for cases in which the transmitting of signaling is indicated and/or scheduled for the transmission timing structure of reception of the transmission timing structure indication.

A border symbol may generally indicate a border of a scheduled transmission in time, and/or within a transmission timing structure. A transmission timing structure may comprise a plurality of symbols, and/or define an interval comprising several symbols (respectively their associated time intervals). In the context of this disclosure it should be noted that a reference to a symbol may be interpreted to refer to the time domain projection or interval or component of the symbol, unless it is clear from the context that the frequency domain component also has to be considered.

If the first transmission timing structure is the transmission timing structure of reception of the transmission timing structure indication, the starting symbol may be determined to be of a higher symbol number than if the first transmission timing structure is a transmission timing structure following the first transmission timing structure in time. Alternatively, or additionally, an ending symbol may be determined to be of a lower symbol number than if the first transmission timing structure is a transmission timing structure following the first transmission timing structure in time.

A transmission timing structure may generally comprise a plurality of symbols defining the time domain extension of the transmission timing structure, and arranged neighboring to each other in a numbered sequence. A timing structure or synchronisation structure may be defined by a succession of such transmission timing structures, which may for example define a timing grid with symbols representing the smallest grid structures. The first transmission timing structure, and/or a border symbol, in particular a starting symbol, may be determined or scheduled in relation to such a timing grid. A scheduled starting symbol may be considered a determined starting symbol. A transmission timing structure of reception may be the transmission timing structure in which the transmission timing structure indication is received, e.g. in relation to the timing grid.

It may in particular be considered that the first transmission timing structure is a slot, and/or that the transmission timing structure of reception is a slot. The first transmission timing structure may be the same or different from the transmission timing structure of reception.

The starting symbol may be determined in relation to a timing structure grid, and/or in relation to a scheduled transmission timing structure like a slot or mini-slot.

Generally, the transmission timing structure indication may be transmitted as control signaling, e.g. in a control channel, in particular a physical control channel. The control signaling may be downlink signaling or sidelink signaling, and/or the control channel may be a downlink channel like a (P)DCCH (Physical Downlink Control CHannel) or sidelink channel like a (P)SCCH (Physical Sidelink Control CHannel).

A border symbol may generally represent a starting symbol for transmitting or an ending symbol for receiving. A starting symbol may in particular be a starting symbol of uplink or sidelink signaling, for example control signaling or data signaling. Such signaling may be on a data channel or control channel, e.g. a physical channel, in particular a physical uplink shared channel (like PUSCH) or a sidelink data or shared channel, or a physical uplink control channel (like PUCCH) or a sidelink control channel. If the starting symbol is associated to control signaling (e.g., on a control channel), the control signaling may be in response to received signaling (in sidelink or downlink), e.g. representing acknowledgement signaling associated thereto, which may be HARQ or ARQ signaling. An ending symbol may represent an ending symbol (in time) of downlink or sidelink transmission or signaling, which may be intended or scheduled for the radio node or user equipment. Such downlink signaling may in particular be data signaling, e.g. on a physical downlink channel like a shared channel, e.g. a PDSCH (Physical Downlink Shared Channel). A starting symbol may be determined based on, and/or in relation to, such an ending symbol.

In some variants a starting symbol and ending symbol are in the same transmission timing structure. In some other variants, the starting symbol may be shifted to a succeeding transmission timing structure (e.g., in a grid). A starting symbol may generally be later in time than an ending symbol it is associated to.

The transmission timing structure indication may generally schedule the transmitting or receiving in a second transmission timing structure.

The transmission timing structure indication may in some variants be comprised in downlink control information or related signaling, in particular in DCI signaling or a related message.

There is also discussed a program product comprising instructions causing processing circuitry to control and/or perform a method as described herein.

Moreover, a carrier medium arrangement carrying and/or storing a program product as described herein may be considered.

The approaches described herein may be considered to implicitly indicate a border symbol for transmitting or receiving signaling, e.g. on one of the described channels, when indicating a transmission timing structure scheduling the signaling. Depending on the scheduled transmission timing structure, different symbol positions may be determined for the border symbol, e.g. in relation to the scheduled transmission timing structure, and/or in relation to an (e.g., underlying or synchronisation) timing grid. Accordingly, overhead is reduced, and flexible scheduling for transmission of signaling is enabled, in particular for quick response signaling (e.g., acknowledgement signaling), which may be particularly beneficial in the context of low latency applications. It may be assumed that both sides of the communication are aware of these approaches if implemented, allowing this implicit signaling approach.

A transmission timing structure indication or slot indication may generally be an acknowledgment resource indication, e.g. an ARI. It may comprise, or comprise of, a number of bits, e.g. 2 or 3 or 4 bits, which may indicate a shift in units of transmission timing structures (e.g., slots) between the transmission timing structure of reception of the transmission timing structure indication, and the scheduled transmission timing structure, e.g. the first transmission timing structure. The shift may in some variants in a range of 0 to 3 or 4 units, in some other up to 5 or more, e.g. for low-latency or Machine-Type-Communication applications.

