Patent Application
20240406987
The present disclosure is generally related to wireless communications systems, and is more particularly related to the determination of the size of downlink control information (DCI) in such systems.
The 5th generation (5G) wireless access technology currently under development by members of the 3rd-Generation Partnership Project (3GPP), known as new radio (NR), will address a variety of usage scenarios from enhanced mobile broadband (eMBB) to ultra-reliable low-latency communications (URLLC) to massive machine-type communications (mMTC). Key NR features include ultra-lean transmission, support for low latency, advanced antenna technologies, and spectrum flexibility including operation in high frequency bands, interworking between high and low frequency bands, and dynamic time division multiplexing (TDD).
Downlink control information (DCI) is used in NR to, among other things, transmit scheduling decisions from the gNB (3GPP terminology for an NR base station) to the UE (3GPP terminology for an access terminal, such as a mobile telephone or a machine-type communications (MTC) device. Different DCI formats are defined for different purposes, differing in, for example, the information carried in the DCI. According to the NR specifications, a UE blindly detects the DCI format based on (among other things) payload size and the RNTI used.
DCI size budget is a major constraint in NR specification to respect UE processing capability. This constraint is captured in 3GPP TS 38.212 as follows:
The DCI formats supported in NR include:
The DCI formats 0_0 and 1_0 are usually referred to as fallback DCI. The DCI formats 0_1 and 1_1 are usually referred to as non-fallback DCI.
The UE blindly attempts to decode DCI messages using the RNTIs the UE is supposed to monitor. If the CRC checks, the DCI is correctly received and intended for this UE, and the UE thus follows the content of the DCI. If the CRC does not check, either the DCI was received in error or it was intended for another UE—in either case, the UE ignores it. Blindly detecting the DCI is done according to search spaces that can be configured in the UE. Search spaces can be either common search spaces (CSS) or UE-specific search spaces (USS). Not all RNTIs or DCI formats are allowed in all search spaces:
To indicate the UE addressed (and sometimes the purpose of the DCI), an identity, referred to as a Radio Network Temporary Identifier (RNTI) is included in the Cyclic Redundancy Check (CRC) of the DCI as transmitted. The RNTIs used to scramble the DCI CRC for each of the various formats are summarized in the below table.
A more detailed description of NR DCI can be found in Section 7.3.1 of 3GPP TS 38.212,v15.3.0.
To reduce device power consumption, a UE may be active on a wide bandwidth for a short time, e.g., in the event of bursty traffic, while being active on a narrow bandwidth for the remaining time. This is commonly referred to as bandwidth adaptation and is addressed in NR by a new concept known as bandwidth part (BWP). A BWP is a subset of contiguous RBs on the carrier. Up to four bandwidth parts can be configured in the UE for each of the UL and DL, but at a given time only one bandwidth part is active per transmission direction. Thus, the UE can receive on a narrow BWP and, when needed, the network can dynamically inform the UE to switch to a wider BWP for reception.
The size of downlink control information (DCI) messages will vary, depending on the format and their contents. However, as noted above, the number of different DCI sizes that a given UE must monitor is limited, by a predetermined DCI size budget, to keep blind decoding procedures manageable. A consequence of this limited budget is that DCI sizes for various formats and purposes must be aligned with one another, so as to ensure that the number of different DCI sizes remains within the specified size budget.
The present disclosure provides several systematic DCI size matching procedures that provide exact instructions on how DCI size matching is to be performed. With these procedures, consistent and exact DCI size matching can be performed, ensuring common understanding of DCI contents between the UE and the network.
Embodiments of techniques disclosed herein include methods, implemented by a UE, for determining DCI sizes for monitoring by the UE. In some of these embodiments, the method comprises determining DCI sizes for monitoring by performing size matching between different DCI formats according to a “Rule 1” as described herein and according to any one or more of “Rule 2” through “Rule 9,” as described herein. Rule 1 specifies that for a frequency domain resource allocation (FDRA) field in each DCI, the UE should use a field size that is a function of the size of a bandwidth part (BWP) wherein the size of the bandwidth part in the function is determined according to a first rule specifying that (i) the size of the BWP is the size of an active uplink BWP or an initial uplink BWP for a DCI format 0_0 monitored in a UE-specific search space (USS), (ii) the size of the BWP is the size of an initial uplink BWP for a DCI format 0_0 not monitored in a USS, (iii) the size of the BWP is the size of an active downlink BWP or an initial downlink BWP or CORESET 0 for a DCI format 1_0 monitored in a USS, (iv) the size of the BWP is the size of an initial downlink BWP for DCI format 1_0 not monitored in a USS, if CORESET 0 is not configured in the cell, and (v) the size of the BWP is the size of CORESET 0 for DCI format 1_0 not monitored in a USS, if CORESET 0 is configured in the cell.
Corresponding techniques disclosed herein include methods, implemented by a base station, for determining DCI sizes for monitoring by a UE served by the base station. In some of these embodiments, the method likewise comprises determining DCI sizes for monitoring by performing size matching between different DCI formats according to the “Rule 1” described herein and according to any one or more of “Rule 2” through “Rule 9,” as described herein.
Other embodiments disclosed herein include UE and base station apparatuses for carrying out the methods summarized above.
The description below applies to the DCI's monitored in an active BWP.
Also, for the padding terminology in the rules below, e.g., “Zeros are added to USS DCI 0_0 . . . ”, it should be read as padding in general (could be zeros, could be ones, could be reserved), not only zeros.
Described below are several “rules” for use in performing DCI size matching, where each rule provides definitions and/or procedures to be followed for determining DCI sizes, while remaining within the predetermined DCI size budget mentioned above. The rules described below may be implemented by a UE, for determining DCI sizes when performing blind decoding and demodulation of DCI messages, as well as by a base station, e.g., a gNB, when assembling and transmitting DCI messages to one or more UEs. The use of these rules in a consistent manner ensures that the UEs and the gNBs have a common understanding of the DCI formats, contents, and structure.
Each of several of the rules below are targeted to specific configurations, e.g., with respect to whether fallback DCI formats are configured for a common search space (CSS) or UE-specific search space (USS). Thus, various embodiments and implementations of the presently disclosed techniques may incorporate one, several, or all of these rules. In some cases below, such as with “Rule 7,” alternative versions of the rule are presented—a given embodiment may implement one of these alternatives. Thus, some embodiments may implement each of the rules below, implementing a single alternative for those rules that are presented with several alternatives. It should be understood, however, that a given embodiment might not implement all of the rules below. A different rule may be substituted for one or more of the below, e.g., for a particular configuration.
Rule 0 specifies a DCI budget size constraint, which the other rules seek to maintain. Rule 1 does not specify a complete rule for DCI sizing, but defines parameters that are used to determine a field size in the DCI, which field size influences the DCI size in each of the subsequent rules.
Several embodiments combine rule 1 with any or all of the subsequent Rules 2-9. An example of a combined rule, according to some embodiments, is also provided below.
Each of several of the rules defined below is accompanied by a “motivation.” These should be understood to provide context and/or justification for the rules but are not limiting.
Motivation: The current DCI size budget description is restricted to C-RNTI. This shall be extended to cover CS-RNTI or SP-CSI-RNTI or MCS-C-RNTI.
Rule description:
The “3+1” DCI budget is extended as follows:
Motivation: In the current field description of FDRA field in fallback DCI 0_0, the size of FDRA (Frequency Domain Resource Assignment) field is a function of the size of the active UL BWP, if DCI 0_0 is monitored in USS and provided that the size budget (in terms of the number of DCI sizes that must be monitored) is satisfied; otherwise the size of FDRA field is given by the initial UL BWP.
In the current field description of FDRA field in fallback DCI 1_0, the size of FDRA field is a function of the size of the DL BWP, if DCI 1_0 is monitored in USS and provided that the size budget is satisfied; otherwise the size of FDRA field is given by the CORESET #0 if CORESET #0 is present and given by the initial DL BWP if CORESET #0 is not present.
Embedding part of the size matching procedure within the FDRA field description in fallback DCI 0_0 and 1_0 makes the size matching procedure as a whole unclear. In this rule, this issue is cleaned up.
Rule description:
Motivation: Non-fallback DCI 0_1 may be scrambled with C-RNTI or CS-RNTI or SP-CSI-RNTI or MCS-C-RNTI, and may be used to schedule SUL and non-SUL. Non-fallback DCI 1_1 may be scrambled with C-RNTI or CS-RNTI or MCS-C-RNTI. It is necessary to align the size of each smaller DCI 0_1 to the maximum size of DCI 0_1; likewise, the size of each smaller DC 1_1 must be aligned to the maximum size of DCI 1_1.
Rule description:
Motivation: This may be a possible configuration for SCell, where CSS is not configured for fallback DCI. In this case:
In either case, USS DCI 0_0 size and USS 1_0 size should be matched, which would guarantee the size budget is met. Two different approaches are detailed below, in rules 3-a and 3-b. Note that as discussed in the background section above, when both fallback DCI and non-fallback DCI are configured in USS, as may be the case for both Rule 3-a and Rule 3-b, they are necessarily in different USSs.
Rule 3-a description:
Rule 3-b description (difference vs. Rule 3-a is underlined):
Motivation: This is a typical configuration, especially for PCell and PSCell. The sizes of fallback DCI 0_0 and 1_0 should be aligned.
Rule 4-a description:
Rule 4-b description (difference vs. Rule 4-a is underlined):
Motivation: DCI size budget (the 3-part of the budget) is satisfied, but USS DCI 0_0 size and USS 1_0 size should still be matched per Rules 5-a or 5-b. For completeness, rule 5-c is included to cover the case without size matching.
Rule 5-a description:
Rule 5-b description (difference vs. Rule 5-a is underlined):
Rule 5-c description:
Motivation: In this case, DCI size budget (the “3” part) is satisfied, and no size matching for non-fallback DCI. Note that adding 1 bit to non-fallback DCI applies only if non-fallback DCI happens to be the same size as USS fallback DCI, which is not present under this case.
Rule 6 description:
Motivation: This is the most complicated case; in general DCI size budget (the “3” part) is not satisfied, but in corner cases it may be satisfied.
There are at least 2 ways to size match.
With method 1 or 2, DCI size matching can be performed according to rule 7-c or 7-d using the rule 7-a or 7-b as a building block.
Rule 7-a description for method 1 (as a building block for rule 7-c/7-cc/7-d)
Rule 7-b description for method 2 (as a building block for rule 7-c/7-cc/7-d)
Rule 7-c description:
Comment on rule 7-c or 7-cc: The above procedure is complicated. A simplified approach would be regardless of whether DCI size budget (before padding) is satisfied or not, simply carry out the following procedure per rule 7-d:
Rule 7-d description:
Motivation: If both DCI 2_0 and DCI 2_1 are configured, it is good to align their size if DCI budget is not satisfied.
Rule 8 description:
Motivation: If DCI 2-2 or DCI 2-3 are configured, it is good to align their sizes to DCI 1_0/0_0 in CSS if DCI budget is not satisfied.
Rule 9 description:
Depending on configuration, Rules 1 to 9 can be applied accordingly. Below shows one example combination of the rules 1 to 9.
Example combined rule description:
The wireless device 50 communicates with a radio node or base station via antennas 54 and a transceiver circuit 56. The transceiver circuit 56 may include transmitter circuits, receiver circuits, and associated control circuits that are collectively configured to transmit and receive signals according to a radio access technology, for the purposes of providing cellular communication services.
The wireless device 50 also includes one or more processing circuits 52 that are operatively associated with the radio transceiver circuit 56. The processing circuitry 52 comprises one or more digital processing circuits 62, e.g., one or more microprocessors, microcontrollers, Digital Signal Processors (DSPs), Field Programmable Gate Arrays (FPGAs), Complex Programmable Logic Devices (CPLDs), Application Specific Integrated Circuits (ASICs), or any mix thereof. More generally, the processing circuitry 52 may comprise fixed circuitry, or programmable circuitry that is specially adapted via the execution of program instructions implementing the functionality taught herein, or may comprise some mix of fixed and programmed circuitry. The processing circuitry 52 may be multi-core.
The processing circuitry 52 also includes a memory 64. The memory 64, in some embodiments, stores one or more computer programs 66 and, optionally, configuration data 68. The memory 64 provides non-transitory storage for the computer program 66 and it may comprise one or more types of computer-readable media, such as disk storage, solid-state memory storage, or any mix thereof. By way of non-limiting example, the memory 64 comprises any one or more of SRAM, DRAM, EEPROM, and FLASH memory, which may be in the processing circuitry 52 and/or separate from the processing circuitry 52. In general, the memory 64 comprises one or more types of computer-readable storage media providing non-transitory storage of the computer program 66 and any configuration data 68 used by the wireless device 50. Here, “non-transitory” means permanent, semi-permanent, or at least temporarily persistent storage and encompasses both long-term storage in non-volatile memory and storage in working memory, e.g., for program execution.
The wireless device 50, e.g., using the processing circuitry 52, may be configured to perform all or some of the techniques described above. For example, the processor 62 of the processor circuitry 52 may execute a computer program 66 stored in the memory 64 that configures the processor 62 to determine DCI sizes for monitoring by the wireless device, by performing size matching between different DCI formats according to rule 1 as described herein and according to any one or more of rules 2-9 as described herein.
The network node 30 includes communication interface circuitry 38 that includes circuitry for communicating with other nodes in the core network, radio nodes, and/or other types of nodes in the network for the purposes of providing data and cellular communication services. The network node 30 communicates with wireless devices via antennas 34 and transceiver circuitry 36. The transceiver circuitry 36 may include transmitter circuits, receiver circuits, and associated control circuits that are collectively configured to transmit and receive signals according to a radio access technology, for the purposes of providing cellular communication services.
The network node 30 also includes one or more processing circuits 32 that are operatively associated with the communication interface circuitry 38 and/or the transceiver circuitry 36. The network node 30 uses the communication interface circuitry 38 to communicate with network nodes and the transceiver circuitry 36 to communicate with user equipments. For ease of discussion, the one or more processing circuits 32 are referred to hereafter as “the processing circuitry 32.” The processing circuitry 32 comprises one or more digital processors 42, e.g., one or more microprocessors, microcontrollers, DSPs, FPGAs, CPLDs, ASICs, or any mix thereof. More generally, the processing circuitry 32 may comprise fixed circuitry, or programmable circuitry that is specially configured via the execution of program instructions implementing the functionality taught herein, or may comprise some mix of fixed and programmed circuitry. The processor 42 may be multi-core, i.e., having two or more processor cores utilized for enhanced performance, reduced power consumption, and more efficient simultaneous processing of multiple tasks.
The processing circuitry 32 also includes a memory 44. The memory 44, in some embodiments, stores one or more computer programs 46 and, optionally, configuration data 48. The memory 44 provides non-transitory storage for the computer program 46 and it may comprise one or more types of computer-readable media, such as disk storage, solid-state memory storage, or any mix thereof. By way of non-limiting example, the memory 44 comprises any one or more of SRAM, DRAM, EEPROM, and FLASH memory, which may be in the processing circuitry 32 and/or separate from the processing circuitry 32. In general, the memory 44 comprises one or more types of computer-readable storage media providing non-transitory storage of the computer program 46 and any configuration data 48 used by the network node 30.
The processing circuitry 32 is also configured, in some embodiments, to determine DCI sizes to be monitored by the UE by performing size matching between different DCI formats according to rule 1 as described herein and according to any one or more of rules 2-9 as described herein.
As shown at block 310, the UE applies Rule 1. According to this rule, for a frequency domain resource allocation (FDRA) field in each DCI format, the UE uses a field size that is a function of the size of a bandwidth part (BWP), wherein the size of the bandwidth part in the function is determined according to a first rule specifying that (i) the size of the BWP is the size of an active uplink BWP or an initial uplink BWP for a DCI format 0_0 monitored in a UE-specific search space (USS), (ii) the size of the BWP is the size of an initial uplink BWP for a DCI format 0_0 not monitored in a USS, (iii) the size of the BWP is the size of an active downlink BWP or an initial downlink BWP or CORESET 0 for a DCI format 1_0 monitored in a USS, (iv) the size of the BWP is the size of an initial downlink BWP for DCI format 1_0 not monitored in a USS, if CORESET 0 is not configured in the cell, and (v) the size of the BWP is the size of CORESET 0 for DCI format 1_0 not monitored in a USS, if CORESET 0 is configured in the cell.
As shown at block 320, the UE applies any one or more of Rules 2-9, as described above.
This may comprise, for example, for each DCI format 0_1 and 1_1 monitored in a USS, applying a second rule specifying that (i) zero padding is added to a DCI format 0_1 smaller than a maximum size of DCI format 0_1, until the size of the DCI format 0_1 is equal to the maximum size of DCI format 0_1, and (ii) zero padding is added to a DCI format 1_1 smaller than a maximum size of DCI format 1_1, until the size of the DCI format 1_1 is equal to the maximum size of DCI format 1_1.
In some embodiments, this may comprise, for each DCI format 0_0 and DCI format 1_0 monitored in a first USS, applying a third rule specifying that (i) if the size of the DCI format 0_0 is smaller than the size of a DCI format 1_0 configured to be monitored by the UE in the first USS, zeroes are added to the DCI format 0_0 until the size of the DCI format 0_0 equals the size of DCI format 1_0 configured to be monitored by the UE in the first USS, (ii) if the size of the DCI format 1_0 is smaller than the size of a DCI format 0_0 configured to be monitored by the UE in the first USS, zeroes are added to the DCI format 1_0 until the size of the DCI format 1_0 equals the size of the DCI format 0_0 configured to be monitored by the UE in the first USS, (iii) if the size of any DCI format 0_1 monitored in a USS other than the first USS is the same as the size of the DCI format 0_0 configured to be monitored by the UE in the first USS or the size of the DCI format 1_0 configured to be monitored by the UE in the first USS, a zero is appended to the end of the DCI format 0_1, and (iv) if the size of any DCI format 1_1 monitored in a USS other than the first USS is the same as the size of the DCI format 0_0 configured to be monitored by the UE in the first USS or the size of the DCI format 1_0 configured to be monitored by the UE in the first USS, a zero is appended to the end of the DCI format 1_1.
In some embodiments, this may comprise, for each DCI format 0_0 and DCI format DCI 1_0 monitored in a common search space (CSS), applying a fourth rule specifying that (i) if the size of the DCI format 0_0 monitored in the CSS is less than the size of a DCI format 1_0 monitored in the CSS, zeroes are added to the DCI format 0_0 monitored in the CSS until the size of the DCI format 0_0 monitored in the CSS is equal to the size of the DCI format 1_0 monitored in the CSS, and (ii) if the size of the DCI format 1_0 monitored in the CSS is less than the size of a DCI format 0_0 monitored in the CSS, most significant bits of the FDRA field in the DCI format 0_0 are truncated until the size of the DCI format 0_0 monitored in the CSS is equal to the size of the DCI format 1_0 monitored in the CSS. In some of these embodiments, this may further comprise, after applying the fourth rule, applying a fifth rule specifying that, for each DCI format 0_0 monitored in a USS, if the size of the DCI format 0_0 monitored in the USS is less than the size of a DCI format 1_0 monitored in the USS, zeroes are added to the DCI format 0_0 monitored in the USS until the size of the DCI format 0_0 monitored in the USS is equal to the size of the DCI format 1_0 monitored in the USS; and for each DCI format 1_0 monitored in a USS, if the size of the DCI format 1_0 monitored in the USS is less than the size of a DCI format 0_0 monitored in the USS, zeroes are added to the DCI format 1_0 monitored in the USS until the size of the DCI format 1_0 monitored in the USS is equal to the size of the DCI format 0_0 monitored in the USS.
In some embodiments, the method may comprise, responsive to (i) DCI format 0_0 or DCI format 1_0 being configured for monitoring by the UE in a common search space (CSS), and (ii) DCI format 0_0 or DCI format 1_0 being configured for monitoring by the UE in a first USS, and (iii) DCI format 0_1 or DCI format 1_1 being configured for monitoring by the UE in a second USS, applying a sixth rule specifying that: for each DCI format 0_0 monitored in the CSS, the field size for the FDRA field is determined as a function of the initial uplink BWP; for each DCI format 1_0 monitored in the CSS, the field size for the FDRA field is determined as a function of the size of CORESET 0, if CORESET 0 is present, or as a function of the size of the initial downlink BWP, if CORESET 0 is not present; for each DCI format 0_0 monitored in the first USS, if the size of the DCI format 0_0 is smaller than the size of the DCI format 1_0 monitored in the first USS, zeroes are added to the DCI format 0_0 monitored in the first USS until the size of the DCI format 0_0 monitored in the first USS is equal to the size of the DCI format 1_0 monitored in the first USS; and for each DCI format 0_0 monitored in the first USS, if the size of the DCI format 0_0 is greater than the size of the DCI format 1_0 monitored in the first USS, most significant bits of the FDRA field of the DCI format 0_0 monitored in the first USS are truncated until the size of the DCI format 0_0 monitored in the first USS is equal to the size of the DCI format 1_0 monitored in the first USS.
In some embodiments, responsive to (i) DCI format 0_0 or DCI format 1_0 being configured for monitoring by the UE in a common search space, CSS, and (ii) DCI format 0_0 or DCI format 1_0 being configured for monitoring by the UE in a first USS, and (iii) DCI format 0_1 or DCI format 1_1 being configured for monitoring by the UE in a second USS, the method may comprise, after applying the fourth rule, applying a seventh rule according to Rule 7cc described above.
In some embodiments, the method may comprise, responsive to both DCI format 2_0 and DCI format 2_1 being configured for monitoring, applying an eighth rule specifying that: for each DCI format 2_0, if a size budget limiting a number of DCI sizes the UE can be configured to monitor would otherwise be exceeded and if the size of the DCI format 2_0 is less than the size of the DCI format 2_1, zeroes are added to the DCI format 2_0 until the size of the DCI format 2_0 is equal to the size of the DCI format 2_1; and for each DCI format 2_1, if a size budget limiting a number of DCI sizes the UE can be configured to monitor would otherwise be exceeded and if the size of the DCI format 2_1 is less than the size of the DCI format 2_0, zeroes are added to the DCI format 2_1 until the size of the DCI format 2_1 is equal to the size of the DCI format 2_0.
In some embodiments, the method shown in
In some embodiments, the method carried out by the UE may further comprise monitoring one or more configured search spaces for a DCI message targeted to the user equipment, using the determined DCI sizes. This is shown at block 330 of
As shown at block 410, the base station applies Rule 1. According to this rule, for a frequency domain resource allocation (FDRA) field in each DCI format, the base station uses a field size that is a function of the size of a bandwidth part (BWP), where the size of the bandwidth part in the function is determined according to a first rule specifying that (i) the size of the BWP is the size of an active uplink BWP or an initial uplink BWP for a DCI format 0_0 configured to be monitored by the UE in a UE-specific search space (USS), (ii) the size of the BWP is the size of an initial uplink BWP for a DCI format 0_0 not configured to be monitored by the UE in a USS, (iii) the size of the BWP is the size of an active downlink BWP or an initial downlink BWP or CORESET 0 for a DCI format 1_0 configured to be monitored by the UE in a USS, (iv) the size of the BWP is the size of an initial downlink BWP for DCI format 1_0 not configured to be monitored by the UE in a USS, if CORESET 0 is not configured in the cell, and (v) the size of the BWP is the size of CORESET 0 for DCI format 1_0 not configured to be monitored by the UE in a USS, if CORESET 0 is configured in the cell.
As shown at block 420, the base station also applies any one or more of Rules 2-9, as described above.
This may comprise, for example, for each DCI format 0_1 and 1_1 configured to be monitored by the UE in a USS, applying a second rule specifying that (i) zero padding is added to a DCI format 0_1 smaller than a maximum size of DCI format 0_1, until the size of the DCI format 0_1 is equal to the maximum size of DCI format 0_1, and (ii) zero padding is added to a DCI format 1_1 smaller than a maximum size of DCI format 1_1, until the size of the DCI format 1_1 is equal to the maximum size of DCI format 1_1.
In some embodiments, this may comprise, for each DCI format 0_0 and DCI format 1_0 configured to be monitored by the UE in a first USS, applying a third rule specifying that (i) if the size of the DCI format 0_0 is smaller than the size of a DCI format 1_0 configured to be monitored by the UE by the UE in the first USS, zeroes are added to the DCI format 0_0 until the size of the DCI format 0_0 equals the size of the DCI format 1_0 configured to be monitored by the UE in the first USS, (ii) if the size of the DCI format 1_0 is smaller than the size of a DCI format 0_0 configured to be monitored by the UE in the first USS, zeroes are added to the DCI format 1_0 until the size of the DCI format 1_0 equals the size of the DCI format 0_0 configured to be monitored by the UE in the first USS, (iii) if the size of any DCI format 0_1 configured to be monitored by the UE in a USS other than the first USS is the same as the size of the DCI format 0_0 configured to be monitored by the UE in the first USS or the size of the DCI format 1_0 configured to be monitored by the UE in the first USS, a zero is appended to the end of the DCI format 0_1, and (iv) if the size of any DCI format 1_1 configured to be monitored by the UE in a USS other than the first USS is the same as the size of the DCI format 0_0 configured to be monitored by the UE in the first USS or the size of the DCI format 1_0 configured to be monitored by the UE in the first USS, a zero is appended to the end of the DCI format 1_1.
In some embodiments, this may comprise, for each DCI format 0_0 and DCI format DCI 1_0 configured to be monitored by the UE in a common search space (CSS), applying a fourth rule specifying that (i) if the size of the DCI format 0_0 configured to be monitored by the UE in the CSS is less than the size of a DCI format 1_0 configured to be monitored by the UE in the CSS, zeroes are added to the DCI format 0_0 configured to be monitored by the UE in the CSS until the size of the DCI format 0_0 configured to be monitored by the UE in the CSS is equal to the size of the DCI format 1_0 configured to be monitored by the UE in the CSS, and (ii) if the size of the DCI format 1_0 configured to be monitored by the UE in the CSS is less than the size of a DCI format 0_0 configured to be monitored by the UE in the CSS, most significant bits of the FDRA field in the DCI format 0_0 configured to be monitored by the UE in the CSS are truncated until the size of the DCI format 0_0 configured to be monitored by the UE in the CSS is equal to the size of the DCI format 1_0 configured to be monitored by the UE in the CSS. In some of these embodiments, this may further comprise, after applying the fourth rule, applying a fifth rule specifying that, for each DCI format 0_0 configured to be monitored by the UE in a USS, if the size of the DCI format 0_0 configured to be monitored by the UE in the USS is less than the size of a DCI format 1_0 configured to be monitored by the UE in the USS, zeroes are added to the DCI format 0_0 configured to be monitored by the UE in the USS until the size of the DCI format 0_0 configured to be monitored by the UE in the USS is equal to the size of the DCI format 1_0 configured to be monitored by the UE in the USS; and for each DCI format 1_0 configured to be monitored by the UE in a USS, if the size of the DCI format 1_0 configured to be monitored by the UE in the USS is less than the size of a DCI format 0_0 configured to be monitored by the UE in the USS, zeroes are added to the DCI format 1_0 configured to be monitored by the UE in the USS until the size of the DCI format 1_0 configured to be monitored by the UE in the USS is equal to the size of the DCI format 0_0 configured to be monitored by the UE in the USS.
In some embodiments, the method may comprise, responsive to (i) DCI format 0_0 or DCI format 1_0 being configured for monitoring by the UE in a common search space (CSS), and (ii) DCI format 0_0 or DCI format 1_0 being configured for monitoring by the UE in a first USS, and (iii) DCI format 0_1 or DCI format 1_1 being configured for monitoring by the UE in a second USS, applying a sixth rule specifying that: for each DCI format 0_0 configured to be monitored by the UE in the CSS, the field size for the FDRA field is determined a function of the initial uplink BWP; for each DCI format 1_0 configured to be monitored by the UE in the CSS, the field size for the FDRA field is determined as a function of the size of CORESET 0, if CORESET 0 is present, or as a function of the size of the initial downlink BWP, if CORESET 0 is not present; for each DCI format 0_0 configured to be monitored by the UE in the first USS, if the size of the DCI format 0_0 is smaller than the size of the DCI format 1_0 configured to be monitored by the UE in the first USS, zeroes are added to the DCI format 0_0 configured to be monitored by the UE in the first USS until the size of the DCI format 0_0 configured to be monitored by the UE in the first USS is equal to the size of the DCI format 1_0 configured to be monitored by the UE in the first USS; and for each DCI format 0_0 configured to be monitored by the UE in the first USS, if the size of the DCI format 0_0 is greater than the size of the DCI format 1_0 configured to be monitored by the UE in the first USS, most significant bits of the FDRA field of the DCI format 0_0 configured to be monitored by the UE in the first USS are truncated until the size of the DCI format 0_0 configured to be monitored by the UE in the first USS is equal to the size of the DCI format 1_0 configured to be monitored by the UE in the first USS.
In some embodiments, responsive to (i) DCI format 0_0 or DCI format 1_0 being configured for monitoring by the UE in a common search space, CSS, and (ii) DCI format 0_0 or DCI format 1_0 being configured for monitoring by the UE in a first USS, and (iii) DCI format 0_1 or DCI format 1_1 being configured for monitoring by the UE in a second USS, the method may comprise, after applying the fourth rule, applying a seventh rule according to Rule 7cc described above.
In some embodiments, the method may comprise, responsive to both DCI format 2_0 and DCI format 2_1 being configured for monitoring by the UE, applying an eighth rule specifying that: for each DCI format 2_0 configured to be monitored by the UE, if a size budget limiting a number of DCI sizes the UE can be configured to monitor would otherwise be exceeded and if the size of the DCI format 2_0 is less than the size of the DCI format 2_1 configured to be monitored by the UE, zeroes are added to the DCI format 2_0 until the size of the DCI format 2_0 is equal to the size of the DCI format 2_1 configured to be monitored by the UE; and for each DCI format 2_1, if a size budget limiting a number of DCI sizes the UE can be configured to monitor would otherwise be exceeded and if the size of the DCI format 2_1 is less than the size of the DCI format 2_0 configured to be monitored by the UE, zeroes are added to the DCI format 2_1 until the size of the DCI format 2_1 is equal to the size of the DCI format 2_0 configured to be monitored by the UE.
In some embodiments, the method shown in
In some embodiments, the method carried out by the base station may further comprise assembling a DCI message for transmission to the UE, according to one of the determined DCI sizes, and transmitting the DCI message to the UE in a search space configured for the UE. This is shown at block 430 of
Examples of methods and apparatuses according to the present disclosure include, but are not limited to, the following:
Example embodiment 1. A method, in a user equipment, for determining downlink control information, DCI, sizes for monitoring by the user equipment, UE, the method comprising:
Example embodiment 2. The method of example embodiment 1, further comprising monitoring one or more configured search spaces for a DCI message targeted to the user equipment, using the determined DCI sizes.
Example embodiment 3. A method, in a base station, for determining downlink control information, DCI, sizes to be monitored by a user equipment, UE, served by the base station, the method comprising:
Example embodiment 4. The method of example embodiment 3, further comprising:
Example embodiment 5. A user equipment, UE, for use in a wireless communications system, the UE being adapted to:
Example embodiment 6. The UE of example embodiment 5, the UE being further adapted to monitor one or more configured search spaces for a DCI message targeted to the user equipment, using the determined DCI sizes.
Example embodiment 7. A base station, for use in a wireless communications system, the base station being adapted to:
Example embodiment 8. The base station of example embodiment 7, the base station being further adapted to:
| Number | Date | Country | |
|---|---|---|---|
| 62751018 | Oct 2018 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 17287047 | Apr 2021 | US |
| Child | 18775535 | US |
