Patent Description:
US patent application <CIT> discloses systems and methods for enabling diversity in the time domain wherein a user equipment receives an indication that a physical channel is repeated over a set of subframes and an indication that the UE can assume that a first subset of the repetitions of the physical channel and a reference signal will use a first precoder.

<NPL>" discloses reusing an already estimated channel from a previous slot as a priori information when performing channel estimation for the next slot in case of physical downlink shared channel (PDSCH) repetition.

US patent application <CIT> discloses methods and systems for enhancing interference mitigation using conjugate symbol repetition and phase randomization on a set of subcarriers.

The present disclosure provides a method of transmitting data from a user equipment in a 3GPP wireless communication network according to claim <NUM>, a user equipment configured to transmit data in a 3GPP wireless communication network according to claim <NUM>, and a non-transitory computer-readable medium according to claim <NUM>. Preferred embodiments are subject of the dependent claims.

Aspects of the present disclosure provide apparatus, methods, processing systems, and computer readable mediums for applying precoding patters to shared channel transmission repetitions to improve the reliability of data transmissions, such as repetitions on the physical downlink shared channel (PDSCH) and physical uplink shared channel (PUSCH).

For example, the wireless communication network <NUM> may be a New Radio (NR) or <NUM> network.

As illustrated in <FIG>, the wireless network <NUM> may include a number of base stations (BSs) <NUM> and other network entities. A BS may be a station that communicates with user equipments (UEs). Each BS <NUM> may provide communication coverage for a particular geographic area. In 3GPP, the term "cell" can refer to a coverage area of a Node B (NB) and/or a Node B subsystem serving this coverage area, depending on the context in which the term is used. In NR systems, the term "cell" and next generation NodeB (gNB), new radio base station (NR BS), <NUM> NB, access point (AP), or transmission reception point (TRP) may be interchangeable. In some examples, the base stations may be interconnected to one another and/or to one or more other base stations or network nodes (not shown) in wireless communication network <NUM> through various types of backhaul interfaces, such as a direct physical connection, a wireless connection, a virtual network, or the like using any suitable transport network.

In some examples, access to the air interface may be scheduled, wherein a. A scheduling entity (e.g., a base station) allocates resources for communication among some or all devices and equipment within its service area or cell.

<FIG> illustrates example components of BS <NUM> and UE <NUM> (as depicted in <FIG>), which may be used to implement aspects of the present disclosure. For example, antennas <NUM>, processors <NUM>, <NUM>, <NUM>, and/or controller/processor <NUM> of the UE <NUM> and/or antennas <NUM>, processors <NUM>, <NUM>, <NUM>, and/or controller/processor <NUM> of the BS <NUM> may be used to perform the various techniques and methods described herein, such as illustrated and described below with respect to <FIG> and <FIG>-9D.

A mini-slot is a subslot structure (e.g., <NUM>, <NUM>, or <NUM> symbols).

To improve data transmission reliability, it may be desirable to repeat data transmissions between a transmitting device and a receiving device. Such repeated data transmissions improve the likelihood that the receiver receives at least one correct version of the data. This may be particularly useful in noisy radio environments or where channel conditions are poor.

Precoding is a form of spatial diversity processing that can be used to further improve the reliability of repeated data transmissions (e.g., in beamforming applications). Generally speaking, precoding may be implemented with single-stream or multi-stream (or multi-layer) transmission in multi-antenna wireless communication systems. For example, in single-stream beamforming, the same signal is emitted from a plurality of transmit antennas with appropriate weighting (e.g., phase and amplitude) such that the signal power is maximized at the receiver. However, when the receiver has multiple antennas, single-stream beamforming may not be able to simultaneously maximize the signal level at all of the receive antennas. Thus, in order to maximize the throughput in multiple receive antenna systems, multi-stream transmission is generally preferred.

In point-to-point systems, precoding means that multiple data streams are emitted from the transmit antennas with independent and appropriate weightings to maximize the signal level at all of the receive antennas such that the link throughput is maximized at the receiver. This method may be particularly useful, for example, in maximizing total throughput in multi-user MIMO applications, where the data streams are intended for different users. These applications may be referred to as spatial division multiple access (SDMA). Precoding in the downlink of cellular networks, sometimes referred to as network MIMO or coordinated multipoint (CoMP), is a generalized form of multi-user MIMO that can be implemented using the techniques described herein.

<FIG> illustrate examples of repeating transmissions on shared channels during inter-slot and intra-slot time periods.

For example, <FIG> illustrates an example of repeating transmissions <NUM> on a physical downlink shared channel (PDSCH). In this example, the PDSCH data is repeated four times, once in each of four successive slots (Slots <NUM>-<NUM>). This type of repetition may be referred to as inter-slot repetition. As explained above, in some instances (e.g., LTE), each slot may be one half of a subframe, i.e., one half of a transmission time interval (TTI). In other instance (e.g., NR), each slot may be one TTI. Note that the relative size of each PDSCH repetition within each slot in <FIG> is not intended to be representative of the proportion of the time or data capacity used by the PDSCH repetition in each slot.

As another example, <FIG> illustrates an example of repeating transmissions <NUM> on a physical downlink shared channel (PDSCH) within a single slot. This type of repetition may be referred to as intra-slot repetition. In this example, each of the PDSCH repetitions takes place within a mini-slot i.e., a portion of a single slot. In this example, there are four mini-slots within Slot <NUM>, but in other examples there may be any number of mini-slots within a single slot. In the LTE context, the mini-slots may correspond to shortened TTIs, i.e., sTTIs. In NR, TTIs are scalable by design.

While <FIG> are illustrated with PDSCH repetitions, these example repetition patterns are equally applicable to PUSCH repetitions or repetitions of other channels in other instances.

As another example, <FIG> illustrates an example of repeating transmissions <NUM> on a physical uplink shared channel (PUSCH) both within a single slot and between slots. This type of repetition may be referred to as hybrid-slot repetition. In this example, two of the PUSCH repetitions takes place within Slot <NUM> and two additional repetitions take place within Slot <NUM>. In this example, there are two mini-slots within Slot <NUM> and within Slot <NUM> (not shown), but in other examples there may be any number of mini-slots within a single slot.

While <FIG> is illustrated with PUSCH repetitions, these example repetition patterns are equally applicable to PDSCH repetitions or repetitions of other channels in other instances.

As another example, <FIG> illustrates an example of repeating transmissions <NUM> on a physical downlink shared channel (PDSCH) and a physical uplink shared channel (PUSCH). In this example, the PDSCH data is repeated two times, once in each of two non-successive slots (Slots <NUM> and <NUM>). Further, the PUSCH data is repeated two times, once in each of two other non-successive slots (Slots <NUM> and <NUM>). This type of repetition may be referred to as interleaved repetition.

While <FIG> is illustrated with PDSCH and PUSCH data transmissions interleaved in successive slots, in other examples the PDSCH and PUSCH data transmissions (or transmissions of other channels or subchannels) may be interleaved within a single slot, e.g., within mini-slots as depicted in <FIG>.

In each of the examples illustrated in <FIG>, there are four total repetitions of data depicted. In other examples, there may be more or fewer repetitions. Further, in <FIG>, each repetition is the same type of data (i.e., PDSCH or PUSCH), while in <FIG> there are different types of data (i.e., PDSCH and PUSCH). In other examples, there may be different configurations.

<FIG> illustrates an example method <NUM> for transmitting data from a device in a wireless communication network. For example, method <NUM> may be performed by a user equipment, such as described above with respect to <FIG> and <FIG>, or by a transmission device, as described below with respect to <FIG> and <FIG>.

Method <NUM> begins at step <NUM> where a number of repetitions to transmit data in a wireless communication network is determined. For example, as described above with respect to <FIG>, data may be repeatedly transmitted on shared channels in one or more slots. In some cases, the number of repetitions is based on channel conditions. For example, more repetitions may be determined when channel conditions are poor and fewer repetitions may be determined when channel conditions are good. In some cases, there may be a default number of repetitions, which may be deviated from based on channel conditions, mobility of a transmission device, or other conditions that may affect the likelihood of the data transmission being successfully received by an intended receiver.

Method <NUM> then proceeds to step <NUM> where a precoding pattern is determined that specifies a precoder to be applied to each repetition of the number of repetitions. For example, as described below with respect to <FIG>, a precoding pattern may define different precoders that are used for different channels or subchannels. The precoders may be, for example, precoding matrices that are used to improve spatial diversity techniques. In some cases, the precoding pattern is selected based on a condition of the device. For example, the condition may relate to mobility of the device (e.g., whether it is moving or not, how fast it is moving, in what direction it is moving, etc.). In some cases, determining a precoding pattern includes selecting a precoding pattern from a plurality of preconfigured precoding pattern stored in a memory of a device, such as a UE or base station, as described above with respect to <FIG> and <FIG>, or a transmission device or reception device, as described below with respect to <FIG> and <FIG>.

Method <NUM> then proceeds to step <NUM> where the data is transmitted according to the number of repetitions and according to the precoding pattern. For example, as described below with respect to <FIG>, many different precoding patterns can be applied based on the number of channels or subchannels and the number repetitions.

In some cases, the precoding pattern specifies at least a first precoder associated with a first subchannel and a second precoder associated with a second subchannel.

Further, in some cases transmitting the data according to the precoding pattern comprises interleaving transmissions of the data (e.g., repetitions) on the first subchannel with transmissions of the data on the second subchannel, while in other cases transmitting the data according to the precoding pattern comprises repeating all transmissions of the data on the first subchannel before any transmissions of the data on the second subchannel.

In some cases, at least one of the first subchannel and the second subchannel comprises a physical downlink shared channel (PDSCH). In further cases, at least one of the first channel and the second channel comprises a physical uplink shared channel (PUSCH). In other cases, at least one of the first subchannel and the second subchannel may be other channels or subchannels associated with a radio access technology, such as LTE or NR, as described above. Further as described with respect to <FIG>, the data may be transmitted during at least one of a plurality of slots, a plurality of mini-slots within a single slot, or a plurality of mini-slots across several slots.

Though not shown in <FIG>, method <NUM> may also include performing a number of channel estimations for use in the transmitting, wherein the number of channel estimations depends on a number of different precoders specified in the precoding pattern.

Method <NUM> may also include receiving a plurality of precoding patterns. For example, a user equipment may receive preconfigured precoding patterns from a network device, such as a base station. In some cases, the plurality of precoding patterns are received via radio resource control (RRC) signaling.

Method <NUM> may also include receiving signaling indicating which of the precoding patterns to use. In some cases, the signaling is received via downlink control information (DCI).

The type of spatial diversity implemented using method <NUM> improves the reliability of the data transmission on the receiving end. For example, by taking advantage of channel-specific conditions, the various precoders may improve the reliability of the data transmissions from transmission device <NUM> to reception device <NUM>. Improving the reliability of the data transmission beneficially reduces retransmission of the data due to errors, which leads to better utilization of wireless resources and faster and more complete data transmission. Further, improving the reliability of the data transmission beneficially reduces processing load and power usage at each of transmission device <NUM> and a reception device <NUM>. Further yet, improving the reliability of the data transmission beneficially provides more access to shared channel resources in multi-device environments, such as in the case of a radio access network as described with respect to <FIG>.

<FIG> illustrate examples of repeating transmissions on shared channels during inter-slot and intra-slot time periods using different precoder patterns.

For example, <FIG> illustrates an example of repeating transmissions <NUM> on a physical downlink shared channel (PDSCH) according to a precoding pattern. Like the example in <FIG>, here the PDSCH data is repeated four times, once in each of four successive slots (Slots <NUM>-<NUM>) (i.e., inter-slot repetition). However, here, PDSCH Repetition <NUM> and PDSCH Repetition <NUM> (during Slots <NUM> and <NUM>) are precoded using Precoder <NUM> while PDSCH Repetition <NUM> and PDSCH Repetition <NUM> (during Slots <NUM> and <NUM>) are precoded using Precoder <NUM>. Thus, in this precoding pattern, all repetitions associated with a particular precoder (e.g., Precoder <NUM>) are transmitted before all repetitions with another precoder (e.g., Precoder <NUM>). Precoder <NUM> may be a first precoding matrix associated with a first physical subchannel and Precoder <NUM> may be a second precoding matrix associated with a second physical subchannel.

In the example depicted in <FIG>, it may be necessary to perform at least two channel estimations i.e., one for each precoder and associated physical subchannel. This is especially true where, for example, a transmission device like a UE is mobile. Because a mobile transmission device will experience changing channel conditions based on its mobility, transmission performance will be improved if a precoder is based on current channel conditions.

As another example, <FIG> illustrates an example of repeating transmissions <NUM> on a physical downlink shared channel (PDSCH) within a single slot (i.e., intra-slot repetition) according to another precoding pattern. Like in <FIG>, in this example, each of the PDSCH repetitions takes place within a mini-slot within Slot <NUM>. However, here, PDSCH Repetitions <NUM>-<NUM> are precoded using Precoders <NUM>-<NUM>, respectively. Thus, in this example, each repetition uses a different precoder and no precoders are repeated during the repetitions. As above, Precoders <NUM>-<NUM> may each be associated with a different precoding matrix and a different physical channel or subchannel.

In the example depicted in <FIG>, it may be necessary to perform at least four channel estimations i.e., one for each precoder and associated physical channel or subchannel. While there may be a minor increase in transmission overhead to perform the channel estimations, generally this will be more than offset by the improved reliability of the data transmission (e.g., in the avoidance of need for retransmission).

As another example, <FIG> illustrates an example of repeating transmissions <NUM> on a physical uplink shared channel (PUSCH) both within a single slot and between slots (i.e., hybrid-slot repetition) according to another precoding pattern. As above in <FIG>, two of the PUSCH repetitions takes place within Slot <NUM> and two additional repetitions take place within Slot <NUM>. However, in this example, each of the PUSCH repetitions during Slot <NUM> is transmitted according to different precoders associated with different physical channels or subchannels. Specifically, in this example PUSCH Repetition <NUM> is transmitted with Precoder <NUM> on a first physical subchannel associated with Precoder <NUM>, and PUSCH Repetition <NUM> is transmitted on a second physical subchannel associated with Precoder <NUM>. Further, according to this example precoding pattern, each repetition during each slot is transmitted with a different precoder, like in <FIG>, though here the precoders are repeated during the transmissions of the total number the repetitions, unlike in <FIG>.

In the example depicted in <FIG>, it may be necessary to perform at least two channel estimations i.e., one for each precoder and associated physical channel or subchannel. However, three channel estimations may be performed in some cases depending on the timing of the repetitions and the status of the transmission device. For example, where a transmission device (e.g., a UE) is mobile, a first channel estimation may be performed before PUSCH Repetition <NUM>, a second channel estimation may be performed before PUSCH Repetitions <NUM> and <NUM>, and then a third channel estimation may be performed before PUSCH Repetition <NUM>. The third channel estimation may be necessary because the channel conditions may have changed significantly between PUSCH <NUM> and PUSCH <NUM> (i.e., where the repetitions are non-consecutive) according to the depicted precoding pattern.

As another example, <FIG> illustrates an example of repeating transmissions <NUM> on different channels, such as the physical downlink shared channel (PDSCH) and the physical uplink shared channel (PUSCH), as may be implemented in a time division duplex (TDD) scheme. In this example, the PDSCH data is repeated two times, once in each of two non-consecutive slots (Slots <NUM> and <NUM>). Further, the PUSCH data is repeated two times, once in each of two other non-consecutive slots (Slots <NUM> and <NUM>). Thus, in this example, the repetition of different physical channels (here, PDSCH and PUSCH) is interleaved on different subchannels (here, physical subchannels associated with Precoder <NUM> and Precoder <NUM>). Note that in this example the PDSCH and PUSCH data transmissions are interleaved in successive slots, but in other examples the PDSCH and PUSCH data transmissions may be interleaved within a single slots, e.g., within mini-slots. Further, while in this example the interleaving pattern is an every-other pattern, with respect to both the subchannels and the physical channels, in other examples the interleaving pattern may be different. For example, if there was priority for downlink shared data, then a repetition pattern may include more PDSCH repetitions than PUSCH repetitions. In other words, the number of repetitions for each channel or subchannel need not be equal.

In the example depicted in <FIG>, it may be necessary to perform at least two channel estimations i.e., one for each precoder and associated physical channel or subchannel. For example, this may be the case where the transmission device is not mobile. However, four channel estimations may be performed in some cases depending on the timing of the repetitions and the mobility of the transmission device. For example, where a transmission device (e.g., a UE) is mobile, a first channel estimation may be performed before PDSCH Repetition <NUM>, a second channel estimation may be performed before PUSCH Repetition <NUM>, a third channel estimation may be performed before PDSCH Repetition <NUM>, and a fourth channel estimation may be performed before PUSCH Repetition <NUM>. Though there are only two precoders in this example, the third and fourth channel estimations may be necessary because the channel conditions may have changed significantly between, for example, PDSCH <NUM> and PDSCH <NUM>, which are non-consecutive according to the depicted precoding pattern.

Further, in other instances, the interleaved repetitions in <FIG> may all be the same type of channel. For example, Slot <NUM>, could be a second repetition of the PDSCH data according to Precoder <NUM>; Slot <NUM> could be a third repetition of the PDSCH data according to Precoder <NUM>; and Slot <NUM> could be a fourth repetition of the PDSCH data according to Precoder <NUM>. As yet another example of interleaving repetitions of data from the same channel using multiple precoders, Slot <NUM>, could be a first repetition of the PUSCH data according to Precoder <NUM>; Slot <NUM> could be a second repetition of the PUSCH data according to Precoder <NUM>; Slot <NUM> could be a third repetition of PUSCH data according to Precoder <NUM>; and Slot <NUM> could be a fourth repetition of the PUSCH data according to Precoder <NUM>. Other examples are possible.

In each of the examples illustrated in <FIG>, there are four total repetitions of data. In other examples, there may be more or fewer repetitions. For example, there may be two repetitions, or eight repetitions, or sixteen repetitions, or any other number as per a particular implementation. In some cases, the number of repetitions may be dynamically changed according to channel conditions where more repetitions are selected when channel conditions are poor and fewer repetitions are selected when channel conditions are good.

In <FIG>, each repetition is on the same type of channel (i.e., PDSCH or PUSCH), while in <FIG> the repetitions occur on different types of channels (i.e., PDSCH and PUSCH). In other examples, there may be different configurations, for example, using different physical channels associated with a particular radio access technology, such as LTE or NR. For example, repetition of control channel data, such as the physical downlink control channel (PDCCH), physical uplink control channel (PUCCH), the group common PDCCH (GC PDCCH), and others.

In each of the examples illustrated in <FIG>, there are either two or four precoders. In other examples, there may be different numbers of precoders. For example, there could be three, six, or eight precoders associated with three, six, or eight channels or subchannels. In some instances, there may be as many precoders as there are antenna elements associated with a transmitting device. The examples depicted in in <FIG> are not intended to be limiting of the number or arrangement of precoders.

<FIG> illustrates aspects of a data transmission system <NUM> including transmission device <NUM> and reception device <NUM>. Transmission device <NUM> may be configured to perform the method described above with respect to <FIG>.

As illustrated, modulation component <NUM> of transmission device <NUM> receives data for transmission (e.g., a bit stream) and modulates the data into symbols for transmission. Layer mapping component <NUM> then maps the symbols to layers (e.g., logical layers and/or physical layers) for transmission. In some examples, each physical layer may be associated with a subchannel and an individual antenna element. Finally precoding component <NUM> may precode the symbols using one or more precoders based on precoding patterns, for example as described above with respect to <FIG>. In some examples, the precoders are based on precoding data (e.g., a precoding matrix indicator) received from precoding matrix indication component <NUM>. In other examples, the precoders may be preconfigured and stored in a memory of a device, such as transmission device <NUM>.

In some cases, precoding component <NUM> of transmission device <NUM> may apply different precoding patterns to the data for transmission. Where the data for transmission will be repeated (e.g., as discussed above with respect to <FIG>), precoding component <NUM> may apply different precoders to the data for transmission based on different physical channels or subchannels on which the data will be transmitted. For example, the data may be transmitted on one or more of physical channels or subchannels P-<NUM> to P-<NUM>, and each physical channel or subchannel may have its own precoder.

Reception device <NUM> may generate channel estimation data based on reference data transmitted by transmission device <NUM>. For example, reception device <NUM> may receive uplink physical reference signals, such as demodulation reference signals (DMRS), which are associated with transmissions on the physical uplink shared channel (PUSCH) and physical uplink control channel (PUCCH). As another example, reception device <NUM> may receive sounding reference signals, which are used to facilitate frequency-dependent scheduling. As yet another example, reception device <NUM> may receive downlink reference signals (DLRS). Thus, channel estimation component <NUM> may receive different types of reference data in order to generate channel estimation data, which may be used by other components of reception device <NUM>.

Precoding matrix indication component <NUM> may generate precoding data, such precoding matrix indicators (PMIs), based on the channel estimation data, The precoding data may be provided to transmission device <NUM> in order for transmission device <NUM> to apply different precoders, as discussed above.

Rank indication component may generate rank indication data (e.g., a rank indicator (RI)) based on the channel estimation data. The rank indication data may indicate the number of symbols that can be transmitted at once by transmission device <NUM>.

Reception device <NUM> receives data transmitted by data transmission device <NUM>. For example, reception device <NUM> may receive repeated data transmissions according to different precoding patterns, as discussed above with respect to <FIG>. Postcoding component <NUM> reverses the effect of the precoding performed by precoding component <NUM> of transmission device <NUM>. Thereafter, layer demapping component <NUM> combines the data transmitted on different layers and then demodulation component <NUM> demodulates the data (e.g., back to a bitstream) to complete the transmission process.

In some examples, transmission device <NUM> may be a user equipment, as described above with respect to <FIG> and <FIG>, or a communication device as described in <FIG>, below. In other examples, transmission device <NUM> may be a base station, as described above with respect to <FIG> and <FIG>.

<FIG> illustrates a communications device <NUM> that may include various components (e.g., corresponding to means-plus-function components) configured to perform operations for the techniques disclosed herein, such as the operations illustrated and described with respect to <FIG> and <FIG>-9D. The transceiver <NUM> is configured to transmit and receive signals for the communications device <NUM> via an antenna <NUM>, such as the various signals described herein.

The processing system <NUM> includes a processor <NUM> coupled to a computer-readable medium/memory <NUM> via a bus <NUM>. In certain aspects, the computer-readable medium/memory <NUM> is configured to store instructions that when executed by processor <NUM>, cause the processor <NUM> to perform the operations illustrated and described with respect to <FIG> and <FIG>-9D, or other operations for performing the various techniques discussed herein.

In certain aspects, the processing system <NUM> further includes a determining component <NUM> for performing the operations illustrated and described with respect to <FIG> and <FIG>-9D. Additionally, the processing system <NUM> includes a transmitting component <NUM> for performing the operations illustrated and described with respect to <FIG> and <FIG>-9D. Additionally, the processing system <NUM> includes a receiving component <NUM> for performing the operations illustrated in illustrated and described with respect to <FIG> and <FIG>-9D. The determining component <NUM>, transmitting component <NUM>, and receiving component <NUM> may be coupled to the processor <NUM> via bus <NUM>. In certain aspects, the determining component <NUM>, transmitting component <NUM>, and receiving component <NUM> may be hardware circuits. In certain aspects, the determining component <NUM>, transmitting component <NUM>, and receiving component <NUM> may be software components that are executed and run on processor <NUM>.

For example, instructions for performing the operations described herein and illustrated and described with respect to <FIG> and <FIG>-9D.

Claim 1:
A method of transmitting data from a user equipment, UE (<NUM>; <NUM>) in a 3GPP wireless communication network, comprising:
receiving one or more precoding patterns from a network device of the 3GPP wireless communication network via radio resource control, RRC, signaling;
determining (<NUM>) a number of repetitions to transmit data in the 3GPP wireless communication network;
determining (<NUM>) a precoding pattern of the one or more precoding patterns that specifies at least one precoder to be applied to each repetition of the number of repetitions; and
transmitting (<NUM>) the data according to the number of repetitions and according to the precoding pattern.