CN112616187A

CN112616187A - Method and user equipment for cross-time-slot scheduling

Info

Publication number: CN112616187A
Application number: CN202011053571.3A
Authority: CN
Inventors: 吴威德; 李承训; 廖怡茹; 廖培凯
Original assignee: MediaTek Inc
Current assignee: MediaTek Inc
Priority date: 2019-10-04
Filing date: 2020-09-29
Publication date: 2021-04-06

Abstract

The invention provides a cross-time-slot scheduling method and User Equipment (UE). The method includes receiving, by a UE, an RRC configuration from a base station in a mobile communication network, the RRC configuration including one or more RRC-configured minimum applicable scheduling offset values for cross-slot scheduling; decoding, when a UE receives DCI on a PDCCH, the DCI including a minimum applicable scheduling offset indicator for active BWPs; and determining a minimum applicable scheduling offset value for active BWP based on the one or more RRC configured minimum applicable scheduling offset values and the minimum applicable scheduling offset indicator. According to the present invention, the minimum applicable scheduling offset value (minimum K0/K2 value) may be dynamically adjusted for the active BWP of a UE operating in cross-slot scheduling.

Description

Method and user equipment for cross-time-slot scheduling

Technical Field

The present invention relates to broadcast channel design, and more particularly, to Cross-Slot scheduling (adaptation) in a next generation 5G New Radio (NR) mobile communication network.

Background

Long-Term Evolution (LTE) systems offer high peak data rates, low latency, improved system capacity, and lower operating costs due to their simple network architecture. The LTE System also provides seamless integration with older wireless networks, such as GSM, CDMA, and Universal Mobile Telecommunications System (UMTS). In an LTE system, an evolved universal terrestrial radio access network (E-UTRAN) includes a plurality of evolved Node-bs (enodebs or enbs) that communicate with a plurality of mobile stations, referred to as User Equipment (UE). LTE systems are enhanced so that they may meet or exceed the International Mobile Telecommunications (IMT-Advanced) fourth generation (4G) standard.

In the case of the millimeter wave band, the signal bandwidth estimation of the next generation 5G NR system will increase up to several hundred MHz (for bands below 6 GHz) and even to GHz values. In addition, the peak NR rate requirement can reach 20Gbps, which is more than ten times that of LTE. Under millimeter wave technology, small cell access, and unlicensed spectrum transmission, three major applications in 5G NR systems include enhanced Mobile Broadband (eMBB), Ultra-Reliable Low Latency Communication (URLLC), and large-scale Machine-Type Communication (MTC). Multiplexing of eMBBs and URLLC within a carrier is also supported.

In LTE/NR networks, a Physical Downlink Control Channel (PDCCH) is used for Downlink (DL) scheduling or Uplink (UL) scheduling of Physical Downlink Shared Channel (PDSCH) or Physical Uplink Shared Channel (PUSCH) transmissions. In general, the PDCCH may be configured to occupy the first one, two, or three OFDM symbols in a subframe. DL/UL scheduling information carried by the PDCCH is referred to as Downlink Control Information (DCI). The DCI format is a predefined format in which DCI is formed by a serving base station and unicasts (unicasts) in a PDCCH to each UE.

Each UE needs to monitor the PDCCH to obtain possible data scheduling information, even during periods when data is not scheduled. For a power-saving (power-saving) mechanism, a concept of cross-slot scheduling is proposed. Under DL cross-slot scheduling, the network may inform the UE: there is a K0 time slot that guarantees a minimum time interval between the PDCCH and the DL packet scheduled by the PDCCH. Similarly, under UL cross-slot scheduling, the network may inform the UE to: there is a K2 time slot that guarantees a minimum time interval between the PDCCH and the UL packet scheduled by the PDCCH. The UE may thus omit unnecessary Radio Frequency (RF) operations if no DL/UL data is scheduled. The UE can use a more efficient receiver configuration for PDCCH reception.

To save power, NR further introduces the concept of fractional Bandwidth (BWP), which consists of contiguous Physical Resource Blocks (PRBs) in the frequency domain and occupies a bandwidth that is a subset of the bandwidth of the relevant carrier. The network may configure multiple UL BWPs and DL BWPs for the UE and require the UE to monitor at most one UL BWP and one DL BWP at the same time. The DL BWPs and UL BWPs that the UE is using or monitoring are referred to as active BWPs, e.g., active DL BWPs and active UL BWPs. For each active DL BWP and each active UL BWP, it may have a minimum applicable (applicable) K0/K2 value (hereinafter also referred to as minimum K0/K2) for cross-slot scheduling purposes.

A solution is needed for a UE to dynamically adjust (adapt) a minimum K0/K2 in an NR wireless communication system.

Disclosure of Invention

In view of the above, the present invention provides a method and a user equipment for cross-slot scheduling with dynamic adjustment of the minimum K0/K2 value.

According to one aspect, the present invention provides a method of cross-slot scheduling, the method comprising: receiving, by a User Equipment (UE), a Radio Resource Control (RRC) configuration from a base station in a mobile communication network, wherein the RRC configuration comprises one or more RRC-configured minimum applicable scheduling offset values for cross-slot scheduling; decoding Downlink Control Information (DCI) provided from the base station when the UE receives the DCI on a Physical Downlink Control Channel (PDCCH), wherein the DCI includes a minimum applicable scheduling offset indicator for an active fractional Bandwidth (BWP); and determining a minimum applicable scheduling offset value for the active BWP based on the minimum applicable scheduling offset value from the one or more RRC-configured minimum applicable scheduling offset values and the minimum applicable scheduling offset indicator.

According to another aspect, the present invention provides a User Equipment (UE) for cross-slot scheduling, the UE comprising a receiver, a decoder and a scheduling processor. The receiver receives an RRC configuration from a base station in the mobile communication network, wherein the RRC configuration includes one or more RRC-configured minimum applicable scheduling offset values for cross-slot scheduling. A decoder is configured to decode, when the UE receives DCI on a PDCCH, the DCI provided from the base station, wherein the DCI includes a minimum applicable scheduling offset indicator for active BWP. The scheduling processor determines a minimum applicable scheduling offset value for the active BWP based on information from one or more RRC configured minimum applicable scheduling offset values and the minimum applicable scheduling offset indicator.

According to the present invention, the minimum applicable scheduling offset value (minimum K0/K2 value) may be dynamically adjusted for the active BWP of a UE operating in cross-slot scheduling.

Many objects, features and advantages of the present invention will become apparent from the following detailed description of the embodiments of the invention, which is to be read in connection with the accompanying drawings. However, the drawings employed herein are for descriptive purposes and should not be considered limiting.

Drawings

Various embodiments of the present invention will be described in detail, with reference to the following figures, wherein like designations denote like elements, and:

fig. 1 illustrates a next generation New Radio (NR) mobile communication network with cross-slot scheduling adjustment (adaptation) to conserve power in accordance with one novel aspect.

Fig. 2 shows a simplified block diagram of a base station and user equipment according to an embodiment of the invention.

Fig. 3 illustrates an example of downlink cross-slot scheduling and UE power saving in accordance with one novel aspect.

Fig. 4 shows a process for L1-based adjustment (adaptation) for cross-slot scheduling according to an embodiment of the present invention.

Fig. 5 illustrates one embodiment of joint indication (join indication) for cross-slot scheduling of active DL BWPs and UL BWPs according to an embodiment of the present invention.

Fig. 6 illustrates an example of parameters for RRC configuration for cross-slot scheduling according to an embodiment of the present invention.

Figure 7 is a flow diagram of a method of cross-slot scheduling adjustment from the perspective of a UE in accordance with one novel aspect.

Detailed Description

Reference will now be made in detail to some embodiments of the invention, examples of which are illustrated in the accompanying drawings.

Fig. 1 illustrates a next generation New Radio (NR) mobile communication network 100 with cross-slot scheduling adjustment (adaptation) to conserve power in accordance with one novel aspect. The mobile communication network 100 is an OFDM/OFDMA system including a base station gNB 101 and including a plurality of user equipments (including UEs 102). When there is a downlink packet to be transmitted from the BS to the UE, the UE obtains an assignment (assignment), e.g., a set of radio resources in a Physical Downlink Shared Channel (PDSCH). When a UE needs to transmit a data packet in uplink to a BS, the UE obtains a grant (grant) from the BS, which allocates a Physical Uplink Shared Channel (PUSCH) consisting of a set of uplink radio resources. The UE acquires downlink or uplink scheduling information specific to the UE from a Physical Downlink Control Channel (PDCCH). In addition, broadcast control information is also transmitted to all UEs in the cell in the PDCCH. Downlink and uplink scheduling information and broadcast control information carried by the PDCCH are collectively referred to as Downlink Control Information (DCI).

In the 3GPP LTE system based on OFDMA downlink, a radio resource is divided into a radio frame and subframes, each of which is composed of two slots each having seven OFDMA symbols in the time domain. Each OFDMA symbol is composed of a plurality of OFDMA subcarriers according to a system bandwidth in a frequency domain. A basic unit of the Resource grid is called a Resource Element (RE), which lasts for one OFDMA subcarrier over one OFDMA symbol. In contrast to LTE parameter set (numerology) (subcarrier spacing and symbol length), a variety of parameter sets are supported in the next generation 5G NR system, and the radio frame structure is slightly different according to the parameter set type. For example, a compound having 15KHz and its integer or 2 is proposed^mMultiple sets of parameters for multiple subcarrier spacings, where m is a positive integer. The supported subcarrier spacing may be 15KHz, 30KHz, 60KHz, 120KHz, and 240 KHz. However, regardless of the parameter set, the length of one radio frame is always 10ms, and the length of a subframe/slot is always 1 ms.

Each UE needs to monitor the PDCCH to obtain possible data scheduling information, even during periods when data is not scheduled. For a power saving mechanism, a concept of cross-slot scheduling is proposed. Under DL cross-slot scheduling, the network may inform the UE that there is a K0 time slot guaranteeing a minimum time interval between the PDCCH and the DL packet scheduled by the PDCCH. Similarly, in UL cross-slot scheduling, the network may inform the UE that there is a K2 time slot that guarantees a minimum time interval between the PDCCH and the UL packet scheduled by the PDCCH. The UE may thus omit unnecessary Radio Frequency (RF) operations if DL/UL data is not scheduled. The UE is also able to use a more efficient receiver configuration for PDCCH reception. As shown in fig. 1, the UE 102 receives a PDCCH for DL scheduling in a slot #1, and may perform PDSCH reception in a slot #3 when K0 is 2. Similarly, the UE 102 receives the PDCCH in slot #2, and may perform PDSCH reception in slot #4 when K0 is 2. Note that the values of K0/K2 represent actual applicable scheduling offset values for the downlink and uplink, respectively. On the other hand, the minimum applicable values of K0/K2 (hereinafter also referred to as minimum K0/K2) represent minimum applicable scheduling offset values for the downlink and uplink, respectively. For example, if minK0 is equal to 2, but K0 is set to 3 in DCI (i.e., K0 is set to any value at least equal to minK 0), the PDSCH is scheduled in slot # N +3 through PDCCH in slot # N.

To save power, NR further introduces the concept of fractional Bandwidth (BWP), which consists of contiguous Physical Resource Blocks (PRBs) in the frequency domain and occupies a bandwidth that is a subset of the bandwidth of the relevant carrier. Under BWP operation, the network may configure multiple UL BWPs and DL BWPs for the UE. To save power, the UE is required to monitor at most one UL BWP and one DL BWP at the same time. The DL BWPs and UL BWPs that the UE is using or monitoring are referred to as active BWPs, e.g., active DL BWPs and active UL BWPs. For active DL BWP and active UL BWP, the UE may first be configured by the network through RRC signaling with a minimum K0/K2, e.g., up to two configuration values, and then the UE may dynamically adjust (adapt) this minimum K0/K2 as indicated by the network via DCI on the PDCCH.

According to one novel aspect, a method is presented for dynamically adjusting a minimum applicable scheduling offset value (minimum K0/K2 value) for an active BWP of a UE operating with cross-slot scheduling. In the example of fig. 1, the gNB 101 configures the UE 102 with multiple DL BWPs and UL BWPs, one active DL BWP and one active UL BWP. The UE 102 operates by cross-slot scheduling to save power. At a higher layer (L2 RRC layer), the UE 102 receives an RRC configuration of a set of minimum applicable K0 values for DL cross-slot scheduling and an RRC configuration of a set of minimum applicable K2 values for UL cross-slot scheduling. At the lower layer (L1 physical layer), the UE 102 may dynamically determine the active minimum K0 or K2 value for the active DL BWP or UL BWP based on 1) the 1-bit DCI indicator on the PDCCH or 2) the change in active BWP due to timeout. If the dynamic adaptation is based on a 1-bit DCI indicator, the indicator "0" indicates a minimum K0/K2 value for the first RRC configuration and the indicator "1" indicates a minimum K0/K2 for the second RRC configuration, or if there is only one RRC configured minimum K0/K2 value, the indicator "1" indicates a minimum K0/K2 value of 0 (e.g., no restriction on scheduling offset). Note that the above DCI indicator is for active DL/UL BWP, so that the UE may dynamically adjust the different minimum K0/K2 for the currently active DL/UL BWP based on the DCI indicator rather than based on BWP switching. On the other hand, if the dynamic adjustment is based on an active BWP change due to a timeout, the minimum K0/K2 to work is equal to the minimum K0/K2 value of the first RRC configuration.

Fig. 2 shows a simplified block diagram of a base station 201 and a user equipment 211 according to an embodiment of the invention. For the base station 201, the antenna 207 transmits and receives radio signals. An RF transceiver module 206, coupled to the antenna, receives RF signals from the antenna 207, converts them to baseband signals, and sends them to the processor 203. The RF transceiver 206 also converts a baseband signal received from the processor 203 into an RF signal and transmits to the antenna 207. The processor 203 processes the received baseband signals and invokes different functional modules to perform functions in the base station 201. The memory 202 stores program instructions and data 209 to control the operation of the base station.

Similarly, for the UE 211, the antenna 217 transmits and receives radio signals. The RF transceiver module 216, which is coupled to the antenna, receives the RF signal from the antenna, converts it into a baseband signal, and then transmits it to the processor 213. The RF transceiver 216 also converts a baseband signal received from the processor into an RF signal and transmits to the antenna 217. The processor 213 processes the received baseband signals and invokes different functional modules to perform functions in the UE 211. The memory 212 stores program instructions and data 219 to control the operation of the UE.

The base station 201 and the UE 211 also comprise a number of functional modules and circuits to perform some embodiments of the invention. The different functional blocks and circuits may be implemented by software, firmware, hardware, or any combination thereof. In one example, each functional module or circuit includes a processor and corresponding program code. The functional modules and circuitry, for example, when executed by the processors 203 and 213 (e.g., by executing the program code 209 and 219), cause the base station 201 to configure BWP and cross-slot scheduling for the UE 211, send an RRC configured minimum K0/K2 and a minimum applicable scheduling offset indicator to the UE 211 via PDCCH, and cause the UE 211 to receive RRC signaling and decode PDCCH to adaptively determine the minimum K0/K2 for active DL/UL BWP accordingly.

In one embodiment, the base station 201 configures BWP and cross-slot scheduling operations for the UE 211 via the configuration/control circuitry 208 and schedules downlink reception and uplink transmission over the PDCCH for the UE 211 via a scheduler (scheduler) 205. The configuration signaling and scheduling is then modulated and encoded via encoder 204 for transmission by transceiver 206 via antenna 207. The UE 211 receives configuration and scheduling information through the transceiver 216 via the antenna 217. UE 211 operates under BWP via BWP module 218, decodes PDCCH via decoder 215, and determines the smallest applicable scheduling offset value to work with via control module 214. In one example, the UE 211 dynamically determines the acting minimum applicable scheduling offset value for the active DL BWP or UL BWP based on 1) a 1-bit DCI indicator on the PDCCH or 2) the active BWP change caused by a timeout.

Fig. 3 illustrates an example of downlink cross-slot scheduling and UE power saving in accordance with one novel aspect. In conventional same-slot scheduling, control information (PDCCH) and data information (PDSCH) are scheduled in the same slot. The UE is configured to monitor and receive the PDCCH. After receiving the PDCCH, the UE needs a processing time to decode the PDCCH. Since the UE assumes that there is downlink data in the time slot, the UE keeps the RF transceiver on in order to receive and store all OFDM symbols during the time that the PDCCH is received and decoded. After determining that there is no downlink data for the UE in the time slot, the UE may turn off its RF transceiver. However, when there is no downlink data scheduled for the UE in the same time slot, the UE may waste power monitoring the same slot schedule in each time slot. If the UE knows that there will not be any PDSCH, the UE can turn off its RF receiver and reduce power consumption just after receiving the PDCCH.

In the cross-slot scheduling, a concept of a minimum interval of K0 slots for downlink scheduling and a minimum interval of K2 slots for uplink scheduling is introduced and configured in a network. The network may inform the UE that there are K0/K2 slots with a guaranteed minimum time interval between the PDCCH and the PDCCH scheduled DL/UL data packets, respectively. Taking downlink cross-slot scheduling as an example, the minimum time interval is K0 time slot between scheduling dci (scheduling dci) on PDCCH and scheduled DL data on PDSCH. In other words, if the PDCCH is received in the time slot n, the UE will receive DL data through the PDSCH no earlier than the time slot n + K0. For example, if K0 is 1, the UE turns on its RX function to receive PDCCH in slot #1, the UE will receive PDSCH in slot #2 or later than slot # 2. Since the UE knows that there is no PDSCH in slot #1, its RX may be turned off when PDCCH #1 decoding is performed. After PDCCH #1 decoding, the UE may enter a micro-sleep state until the next slot to save more power. Based on PDCCH #1 decoding, it is assumed that PDSCH is not scheduled for the UE in slot # 2. In slot #2, the UE turns on its RX to receive PDCCH # 2. Since the UE knows that there is no PDSCH in slot #2, its RX may be turned off when PDCCH decoding is performed. After PDCCH #2 decoding, the UE knows that PDSCH is scheduled for the UE in slot # 3. The UE may enter a micro sleep state up to slot #3 to save more power. In slot #3, the UE turns on its RX to receive the PDCCH and continues its RX to receive scheduled downlink data on the PDSCH scheduled by PDCCH # 2. Compared to the same-slot (same-slot) scheduling, it can be seen that when there is no scheduled downlink data on the PDSCH, the UE can save power consumption during PDCCH decoding and can enter a micro-sleep state. Here, the "micro sleep state" is an intermediate low power state in the DRX active mode (active mode) compared to the "deep sleep" in the lowest power state in the DRX inactive mode (active mode). This means that the UE can save power in DRX active mode with no active operation.

The minimum applicable scheduling offset indicator for the minimum K0/K2 adjustment (adaptation) in cross slot scheduling is carried by the DCI, which may be a scheduling DCI, and thus can only be transmitted by the network during DRX active time. However, during the data inactivity time (inactivity time), no data is scheduled. How to indicate to the UE to apply cross-slot scheduling to save power during data inactivity remains uncertain. A TB NACK event may exist when a DCI indicator for a minimum K0/K2 adjustment is carried in the scheduling DCI of the last Transport Block (TB). The base station would then need to schedule retransmissions using cross-slot scheduling, which would impact the data scheduler design assuming co-slot scheduling. If this problem is not solved, cross slot scheduling will not be used for DRX ON duration with data scheduling. To avoid entering cross-slot scheduling when the last TB of a data burst (data burst) is a NACK, one solution is: cross-slot scheduling is entered only after the UE successfully decodes the last TB containing the scheduling DCI, which carries the DCI indicator of minimum K0/K2 for cross-slot scheduling. That is, when the UE is instructed by the DCI to change to a larger minimum applicable K0/K2 value during the active time, the UE applies the target minimum K0/K2 value after an appropriate application delay only after the UE successfully decodes the TB scheduled by the DCI.

Fig. 4 shows a process for L1-based adjustment (adaptation) for cross-slot scheduling according to an embodiment of the present invention. In step 411, UE 401 and network 402 establish a Radio Resource Control (RRC) connection. UE 401 may enter a Discontinuous Reception (DRX) mode to save power. In step 412, network 402 configures UE 401 with cross-slot operation and provides RRC configuration parameters to UE 401. The RRC configuration parameters may include a set of minimum applicable K0/K2 values. Network 402 may also configure BWP operation for UE 401 and provide BWP parameters including one active DL BWP and one active UL BWP. In step 413, the network 402 transmits DCI to the UE 401 for DL/UL scheduling through the PDCCH. The DCI may include a 1-bit indicator for adjusting a minimum K0/K2 value of the active DL/UL BWP. In step 421, UE 401 performs PDCCH decoding to obtain scheduling information and the 1-bit indicator. The UE 401 also detects whether the active BWP has switched to other BWPs due to a timeout (rather than triggered by DCI). In step 431, the UE 401 determines the minimum applicable K0/K2 value based on the decoded DCI indicator or based on the active BWP handover. If the current slot has no PDSCH/PUSCH, UE 401 may enter a micro-sleep state to save power. Otherwise, UE 401 performs PDSCH reception or PUSCH transmission accordingly.

Note that the UE is not expected to receive a different value in the 1-bit indicator before applying the previously indicated minimum K0/K2 value. Specifically, when the DCI indicates the minimum applicable scheduling offset indicator field for the UE, the UE should determine the minimum K0/K2 value to apply, and the previously applied minimum K0/K2 value will be applied until a new value takes effect after an application delay (application delay) X (slot) of a scheduling cell (scheduling cell). The change of the applied minimum applicable scheduling offset indication (scheduling offset indication) carried by the DCI in slot n should be applied in slot n + X of the scheduling cell. It is not desirable to schedule a UE using a DCI that indicates that another change in the applied minimum K0/K2 value for the same active BWP occurs before slot n + X of the scheduling cell. For example, in step 414, the network 402 may transmit a second DCI for DL/UL scheduling to the UE 401 through the PDCCH. The second DCI may include another 1-bit indicator for adjusting the minimum applicable value of K0/K2 for the same active DL/UL BWP. UE 401 may ignore the second DCI indicator if the second DCI occurs before the previously determined minimum applicable K0/K2 value is applied.

Fig. 5 illustrates one embodiment of joint indication (join indication) for cross-slot scheduling of active DL BWPs and UL BWPs according to an embodiment of the present invention. Determining the minimum applicable scheduling offset value for active DL/UL BWP involves three steps: the first step, receiving a group of RRC configuration parameters of the minimum applicable scheduling deviation value; secondly, receiving a dynamic indication carried by the DCI or detecting active BWP switching caused by overtime; and thirdly, final adjustment. In one example, the set of RRC configured minimum applicable K0/K2 values may include only one configuration value. In another example, the set of RRC-configured minimum applicable K0/K2 values may include two configuration values (e.g., a lower-indexed RRC configuration value (first value) and a higher-indexed RRC configuration value (second value)).

As shown in table 500 of fig. 5, for an active dl (ul) BWP with only one RRC configured minimum applicable K0(K2) value, a value of 0 for the 1-bit DCI indicator for cross-slot scheduling adjustment indicates a configured value, and a value of 1 for the 1-bit DCI indicator indicates no restriction (minimum applicable K0/K2 ═ 0). For active dl (ul) BWP with minimum applicable K0/K2 values of two RRC configurations, a value of 0 for the 1-bit DCI indicator for cross-slot scheduling adjustment indicates a first RRC configuration value, and a value of 1 for the 1-bit DCI indicator indicates a second RRC configuration value. In other cases, for example, when the active DL/UL BWP changes due to BWP handover triggered by BWP timer expiration (no 1-bit indicator carried by DCI received), the minimum applicable K0/K2 value also needs to be adjusted. In case of a change in active DL/UL BWP, in order to adjust the minimum applicable K0/K2 value for active BWP, when there are one or two RRC configuration values, the value applied to active BWP is determined by: if a value is an RRC configuration value, a value applied to the active BWP is the configuration value; if the two values are RRC configured values, the value applied to the active BWP is the lowest indexed (lowest-indexed) RRC configured value.

Fig. 6 illustrates an example of parameters for RRC configuration for cross-slot scheduling according to an embodiment of the present invention. The minimum K0/K2 value for the RRC configuration is a subset of all possible values for the existing minimum K0/K2 parameter. In the next generation 5G NR system, a variety of parameter sets are supported, and a radio frame structure may be different according to the types of the parameter sets. For example, a subcarrier spacing (SCS) with 15KHz and its integer or 2 is proposed^mMultiple parameter sets, where m is a positive integer. The supported subcarrier spacing (SCS) may be 15KHz, 30KHz, 60KHz, 120KHz, and 240 KHz. Thus, to cover cross-carrier scheduling with different sets of parameters, for RRC configuration, the minimum applicable K of the configurationThe 0/K2 value takes an integer value between 0 and 16. This is because in order to have the same RF off duration between carriers of different SCS, the time length corresponding to the minK0 value defined for each scheduled carrier should be consistent. In the example of fig. 6, the primary PCell of the 15KHz SCS applies minK 0-2, and the secondary SCell of the 120KHz SCS should apply minK 0-16, which is associated to the maximum configurable value of the minimum applicable scheduling offset.

In one novel aspect, the UE may suggest a set of preferred minimum applicable K0/K2 values for different sets of parameters to the network. RRC-based UE signaling applied to a proposed set of minimum applicable K0/K2 values for cross-slot scheduling may be provided to the network as UE assistance information and should cover all possible parameter set/SCS cases. Assuming co-carrier scheduling, each proposed value should be in the range of 1 to 4 or 8 slots. For the case of cross-slot scheduling, it is advantageous for UE power saving to agree the length of time corresponding to the minimum applicable K0/K2 value of the configuration of the scheduling cell with the length of time corresponding to the K0/K2 value of the scheduled cell for cross-slot scheduling. Then, based on the minimum applicable value of K0/K2 suggested by the UE, the network can determine the parameters of the RRC configuration.

Figure 7 is a flow diagram of a method of cross-slot scheduling adjustment from the perspective of a UE in accordance with one novel aspect. In step 701, the UE receives a Radio Resource Control (RRC) configuration from a base station in a mobile communication network. The RRC configuration includes one or more RRC configuration (RRC-configured) minimum applicable scheduling offset values for cross-slot scheduling. In step 702, when the UE receives Downlink Control Information (DCI) on a Physical Downlink Control Channel (PDCCH), the UE decodes the DCI provided from the base station. The DCI includes a minimum applicable scheduling offset indicator for an active partial Bandwidth (BWP). In step 703, the UE determines the minimum applicable scheduling offset value for the active BWP based on a joint determination (joint determination) from one or more RRC configured minimum applicable scheduling offset values and minimum applicable scheduling offset indicators.

Although the present invention has been described above in connection with certain specific embodiments, the present invention is not limited thereto. Accordingly, various modifications, adaptations, and combinations of features may be made to the described embodiments without departing from the scope of the invention as set forth in the claims.

Claims

1. A method of cross-slot scheduling, comprising:

receiving, by a user equipment, UE, a radio resource control, RRC, configuration from a base station in a mobile communication network, wherein the RRC configuration comprises one or more RRC configuration minimum applicable scheduling offset values for cross-slot scheduling;

decoding downlink control information, DCI, provided from the base station when the UE receives the DCI on a physical downlink control channel, PDCCH, wherein the DCI includes a minimum applicable scheduling offset indicator for an active fractional bandwidth, BWP; and

determining a minimum applicable scheduling offset value for the active BWP based on the one or more RRC configured minimum applicable scheduling offset values and the minimum applicable scheduling offset indicator.

2. The method of claim 1, wherein each minimum applicable scheduling offset value is represented by a number of slots between scheduled and scheduled slots for downlink cross-slot scheduling or by a number of slots between scheduled and scheduled slots for uplink cross-slot scheduling.

3. The method according to claim 1, wherein, when the one or more RRC-configured minimum applicable scheduling offset values include a first RRC-configured value and a second RRC-configured value, if the minimum applicable scheduling offset indicator is set to "0", the minimum applicable scheduling offset value for the active BWP is equal to the first RRC-configured value; the minimum applicable scheduling offset value is equal to a second RRC configured value if the minimum applicable scheduling offset indicator is set to "1".

4. The method according to claim 1, wherein, when the one or more RRC-configured minimum applicable scheduling offset values comprises one RRC-configured value, if the minimum applicable scheduling offset indicator is set to "0", the minimum applicable scheduling offset value for the active BWP is equal to the RRC-configured value; the minimum applicable scheduling offset value is equal to 0 if the minimum applicable scheduling offset indicator is set to "1".

5. The method of claim 1, wherein the RRC-configured minimum applicable scheduling offset value is in a range of 0 to 16 for different sets of parameters.

6. The method of claim 1, further comprising:

and sending UE auxiliary information to the base station, wherein the UE auxiliary information comprises a set of minimum applicable scheduling offset values preferred by the UE for different parameter sets.

7. The method of claim 1, wherein the UE receives a second DCI with a second indicator before the UE applies the determined minimum applicable scheduling offset value, and wherein the UE ignores the second indicator.

8. The method of claim 1, wherein the UE applies the minimum applicable scheduling offset value only when a scheduled transport block is decoded correctly.

9. The method of claim 1, further comprising:

upon detecting a change in active BWP due to a timeout, determining the minimum applicable scheduling offset value for the active BWP.

10. The method of claim 9, wherein the minimum applicable scheduling offset value is determined to be equal to a first RRC-configured minimum applicable scheduling offset value.

11. A user equipment, UE, for cross-slot scheduling, comprising:

a receiver that receives an RRC configuration from a base station in a mobile communication network, wherein the RRC configuration comprises one or more RRC-configured minimum applicable scheduling offset values for cross-slot scheduling;

a decoder for decoding DCI provided from the base station when the UE receives the DCI on a PDCCH, wherein the DCI includes a minimum applicable scheduling offset indicator for active BWP; and

a scheduling processor to determine a minimum applicable scheduling offset value for the active BWP based on the one or more RRC configured minimum applicable scheduling offset values and the minimum applicable scheduling offset indicator.

12. The UE of claim 11, wherein each minimum applicable scheduling offset value is represented by a number of slots between scheduled and scheduled slots for downlink cross-slot scheduling or by a number of slots between scheduled and scheduled slots for uplink cross-slot scheduling.

13. The UE of claim 11, wherein the minimum applicable scheduling offset value for the active BWP is equal to a first RRC configuration value if the minimum applicable scheduling offset indicator is set to "0"; the minimum applicable scheduling offset value is equal to a second RRC configured value if the minimum applicable scheduling offset indicator is set to "1".

14. The UE of claim 11, wherein, when the one or more RRC-configured minimum applicable scheduling offset values includes one RRC-configured value, if the minimum applicable scheduling offset indicator is set to "0", the minimum applicable scheduling offset value for the active BWP is equal to the RRC-configured value; the minimum applicable scheduling offset value is equal to 0 if the minimum applicable scheduling offset indicator is set to "1".

15. The UE of claim 11, wherein the RRC-configured minimum applicable scheduling offset value is in a range of 0 to 16 for different sets of parameters.

16. The UE of claim 11, further comprising:

a transmitter configured to transmit UE assistance information to the base station, wherein the UE assistance information includes a set of minimum applicable scheduling offset values preferred by the UE for different sets of parameters.

17. The UE of claim 11, wherein the UE receives a second DCI with a second indicator before the UE applies the determined minimum applicable scheduling offset value, and wherein the UE ignores the second indicator.

18. The UE of claim 11, wherein the UE applies the minimum applicable scheduling offset value only when a scheduled transport block is decoded correctly.

19. The UE of claim 11, wherein the UE determines the minimum applicable scheduling offset value for active BWP upon detecting a change in active BWP due to a timeout.

20. The UE of claim 19, wherein the minimum applicable scheduling offset value is determined to be equal to a first RRC-configured minimum applicable scheduling offset value.