WO2022027573A1

WO2022027573A1 - Channel quality information reporting and modulation and coding scheme determination for devices with limited capabilities

Info

Publication number: WO2022027573A1
Application number: PCT/CN2020/107764
Authority: WO
Inventors: Mengzhu CHEN; Qiujin GUO; Xiaoying Ma; Focai Peng; Jun Xu; Jian KANG
Original assignee: Zte Corporation
Priority date: 2020-08-07
Filing date: 2020-08-07
Publication date: 2022-02-10
Also published as: CN116235434A

Abstract

Methods, apparatus, and systems that enable proper Channel Quality Indicator (CQI) reporting and Modulation and Coding Scheme (MCS) determination by communication devices with limited or reduced capabilities are disclosed. In one example aspect, a wireless communication method includes determining, by a communication device, a table comprising one or more combinations of modulation orders and code rates based on a characteristic of a communication device indicating a set of limited capabilities supported by the communication device. The method also includes performing, by the communication device, an operation with a network node based on the table.

Description

CHANNEL QUALITY INFORMATION REPORTING AND MODULATION AND CODING SCHEME DETERMINATION FOR DEVICES WITH LIMITED CAPABILITIES

TECHNICAL FIELD

This patent document is directed generally to wireless communications.

BACKGROUND

Mobile communication technologies are moving the world toward an increasingly connected and networked society. The rapid growth of mobile communications and advances in technology have led to greater demand for capacity and connectivity. Other aspects, such as energy consumption, device cost, spectral efficiency, and latency are also important to meeting the needs of various communication scenarios. Various techniques, including new ways to provide higher quality of service, longer battery life, and improved performance are being discussed.

SUMMARY

This patent document describes, among other things, techniques that enable proper Channel Quality Indicator (CQI) reporting and Modulation and Coding Scheme (MCS) determination by communication devices with limited or reduced capabilities.

In one example aspect, a wireless communication method is disclosed. The method includes determining, by the communication device, a table comprising one or more combinations of modulation orders and code rates based on a characteristic of a communication device indicating a set of limited capabilities supported by the communication device. The method also includes performing, by the communication device, an operation based on the table.

In another example aspect, a wireless communication method is disclosed. The method includes receiving, by a network node, a characteristic of a communication device indicating a set of limited capabilities of the communication device. The method also includes performing, by the network node, an operation with the communication device based on a table determined according to the characteristic of the communication device.

In another example aspect, a communication apparatus is disclosed. The apparatus includes a processor that is configured to implement an above-described method.

In yet another example aspect, a computer-program storage medium is disclosed. The computer-program storage medium includes code stored thereon. The code, when executed by a processor, causes the processor to implement a described method.

These, and other, aspects are described in the present document.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a flowchart representation of a method for wireless communication in accordance with the present technology.

FIG. 2 is a flowchart representation of another method for wireless communication in accordance with the present technology.

FIG. 3 shows an example of a wireless communication system where techniques in accordance with one or more embodiments of the present technology can be applied.

FIG. 4 is a block diagram representation of a portion of a radio station in accordance with one or more embodiments of the present technology can be applied.

DETAILED DESCRIPTION

Section headings are used in the present document only to improve readability and do not limit scope of the disclosed embodiments and techniques in each section to only that section. Certain features are described using the example of Fifth Generation (5G) wireless protocol. However, applicability of the disclosed techniques is not limited to only 5G wireless systems.

In wireless communication systems, communication devices (e.g., terminal devices) can report Channel State Information (CSI) to the network node (e.g., the base station) to allow the network node to be aware of the current communication channel quality and to adjust channel parameters if necessary. CSI comprises a variety of parameters, such as Channel Quality Indicator (CQI) , Precoding Matrix Indicator (PMI) , Rank Indicator (RI) , and/or CSI Reference Signal Resource Indicator (CRI) . Currently, there are three CQI tables and corresponding Modulation and Coding Scheme (MCS) tables defined in the Third-Generation Partnership Project (3GPP) standard for New Ratio (NR) communication technology, indicating different combinations of modulation orders and code rates. However, these tables are designed mainly for enhanced Mobile Broadband (eMBB) and Ultra Reliable Low Latency Communications (URLLC) services. For terminal devices or User Equipment (UE) with limited or reduced capabilities, the maximum modulation order or the maximum code rate supported can be limited. Furthermore, if the device is equipped with fewer receiving antennas, the coverage (especially downlink coverage) can be impacted. There remains a need to for a CQI reporting and MCS determination mechanism that are more suitable for devices with limited or reduced capabilities.

This patent document discloses techniques that can be implemented in various embodiments to facilitate CQI reporting and MCS determination for communication devices that have limited/reduced capabilities. In one example aspect, a communication device can be categorized based on its device type, operation mode, or capabilities so as to allow the device to select the appropriate CQI table for CQI reporting and to determine the appropriate MCS table for transmissions. In another example aspect, new CQI/MCS tables are provided to offer better code rates or modulation orders to the devices with limited or reduced capabilities.

FIG. 1 is a flowchart representation of a method 100 for wireless communication in accordance with the present technology. The method 100 includes, at operation 110, determining, by the communication device, a table comprising one or more combinations of modulation orders and code rates based on a characteristic of a communication device indicating a set of limited capabilities supported by the communication device. The method 100 includes, at operation 120, performing, by the communication device, an operation based on the table.

In some embodiments, the table comprises a Channel Quality Indicator (CQI) table. In some embodiments, performing the operation comprises reporting, by the communication device, CQI information based on the CQI table to a network node. In some embodiments, a transport block corresponding to the CQI information is received with a transport block error probability not exceeding a threshold value.

In some embodiments, the table comprises a Modulation and Coding Scheme (MCS) table. In some embodiments, performing the operation comprises receiving, by the communication device, Modulation and Coding Scheme (MCS) information associated with the MCS table from the network node. In some embodiments, performing the operation comprises performing an uplink transmission or a downlink reception with the network node based on the MCS table by the communication device.

In some embodiments, the characteristic of the communication device comprises at least one of: a device category of the communication device, a capability of the communication device; an operation mode of the communication device, or a combination thereof. In some embodiments, the capability of the communication device comprises at least one of: a bandwidth supported by the communication device, a number of antennas of the communication device, a maximum number of Multiple-Input-Multiple-Output (MIMO) layers supported by the communication device, a maximum modulation order supported by the communication device, a maximum code rate supported by the communication device, a duplex mode supported by the communication device, or a combination thereof.

In some embodiments, the determining of the table is further based on predefined information. In some embodiments, the predefined information comprises at least one of: a transmission direction, whether transform precoding is enabled, or a CQI table selected for CQI reporting. In some embodiments, the predefined information comprises at least one of: a higher layer signaling; a Radio Network Temporary Identifier; a search space set type; a DCI format; a coverage enhancement operation; a Channel Station Information (CSI) type; a resource allocation for a physical channel; one or more resources for a random-access procedure; a subcarrier spacing; a frequency range; or a combination thereof. In some embodiments, the coverage enhancement operation is associated with at least a repetition of a transmission on a downlink physical channel or an uplink physical channel. In some embodiments, the method includes determining, by the communication device, a resource allocated to the repetition of the downlink transmission is invalid due to a condition being satisfied. In some embodiments, the condition comprises at least one of (1) the resource is indicated as an uplink resource by a configuration parameter, (2) the resource is occupied by a synchronization signal or a physical broadcast channel, (3) the resource is occupied by a control resource set (e.g., the CORESET for Type-0 PDCCH search space set) , (4) the resource is indicated as an uplink resource or a flexible resource by a downlink control information (DCI) message , or (5) the resource is indicated as invalid by a higher layer signaling message. In some embodiments, the one or more resources for a random-access procedure comprise at least one of: a preamble sequence, a logical root sequence index, a preamble format, a time resource for the random-access procedure, a frequency resource for the random-access procedure, a configuration index for the random-access procedure, or a repetition of a random-access transmission.

In some embodiments, the method includes reporting, by the communication device, the characteristic of a communication device to a network node indicating a device category that the communication device belongs to. In some embodiments, a minimum spectrum efficiency of the table is equal to or greater than a first threshold. In some embodiments, a combination of a modulation order and a code rate corresponding to the first threshold comprises (1) a modulation order of q and a code rate of 30/1024, (2) a modulation order of q and a code rate of 40/1024, or (3) a modulation order of q and a code rate of 50/1024, wherein q=1 or 2. In some embodiments, a maximum spectrum efficiency of the table is equal to or smaller than a second threshold. In some embodiments, a combination of a modulation order and a code rate corresponding to the second threshold comprises (1) a modulation order of 4 and a code rate of 616/1024, (2) a modulation order of 6 and a code rate of 772/1024, or (3) a modulation order of 6 and a code rate of 873/1024.

In some embodiments, the code rates of the table are equal to or below a third threshold. In some embodiments, the third threshold is associated with a selection of a Low-density Parity Check Code (LPDC) base graph. In some embodiments, the third threshold comprises R + Δ, wherein R is a code rate associated with the selection of a LPDC base graph, and wherein -1/8 ≤ Δ ≤ 1/8.

In some embodiments, the modulation orders of the table are equal to or below a fourth threshold. In some embodiments, a subset of the one or more combinations of the modulation orders and the code rates is same as combinations in another table. In some embodiments, at least one of the one or more combinations of the modulation orders and the code rates is associated with repetition information for a transmission or a resource block of a Channel State Information (CSI) reference resource.

FIG. 2 is a flowchart representation of a method 200 for wireless communication in accordance with the present technology. The method 200 includes, at operation 210, receiving, by a network node, a characteristic of a communication device indicating a set of limited capabilities of the communication device. The method 200 also includes, at operation 220, performing, by the network node, an operation with the communication device based on a table determined according to the characteristic of the communication device.

In some embodiments, the table comprises a Channel Quality Indicator (CQI) table. In some embodiments, performing the operation comprises receiving, by the network node, Channel Quality Indicator (CQI) information associated with the CQI table. In some embodiments, a transport block corresponding to the CQI information is transmitted with a transport block error probability not exceeding a threshold value.

In some embodiments, the table comprises a Modulation and Coding Scheme (MCS) table. In some embodiments, performing the operation comprises transmitting, by the network node, Modulation and Coding Scheme (MCS) information associated with the MCS table to the communication device. In some embodiments, performing the operation comprises performing an uplink reception or a downlink transmission with the communication device based on the MCS table.

In some embodiments, the characteristic of the communication device comprises at least one of: a device category of the communication device, a capability of the communication device, an operation mode of the communication device, or a combination thereof. In some embodiments, the capability of the communication device comprises at least one of: a bandwidth supported by the communication device, a number of antennas of the communication device, a maximum number of Multiple-Input-Multiple-Output (MIMO) layers supported by the communication device, a maximum modulation order supported by the communication device, a maximum code rate supported by the communication device, a duplex mode supported by of the communication device, or a combination thereof.

In some embodiments, the table is determined further based on predefined information. In some embodiments, the predefined information comprises at least one of: a transmission direction, whether transform precoding is enabled, or a CQI table selected for CQI reporting. In some embodiments, the predefined information comprises at least one of: a higher layer signaling; a Radio Network Temporary Identifier; a search space set type; a DCI format; a coverage enhancement operation; a Channel Station Information (CSI) type; a resource allocation for a physical channel; one or more resources for a random-access procedure; a subcarrier spacing; a frequency range; or a combination thereof. In some embodiments, the coverage enhancement operation is associated with at least a repetition of a transmission on a downlink physical channel or an uplink physical channel.

In some embodiments, a resource allocated to the repetition of the downlink transmission is invalid due to a condition being satisfied. In some embodiments, the condition comprises at least one of (1) the resource is indicated as an uplink resource by a configuration parameter, (2) the resource is occupied by a synchronization signal or a physical broadcast channel, (3) the resource is occupied by a control resource set, (4) the resource is indicated as an uplink resource or a flexible resource by a downlink control information (DCI) message, or (5) the resource is indicated as invalid by a higher layer signaling message. In some embodiments, the one or more resources for a random-access procedure comprise at least one of: a preamble sequence, a logical root sequence index, a preamble format, a time resource for the random-access procedure, a frequency resource for the random-access procedure, a configuration index for the random-access procedure, or a repetition of a random-access transmission.

In some embodiments, the method includes receiving, by the network node, the characteristic of the communication device from the communication device indicating a device category that the communication device belongs to. In some embodiments, a minimum spectrum efficiency of the table is equal to or greater than a first threshold. In some embodiments, a combination of a modulation order and a code rate corresponding to the first threshold comprises (1) a modulation order of q and a code rate of 30/1024, (2) a modulation order of q and a code rate of 40/1024, or (3) a modulation order of q and a code rate of 50/1024, wherein q=1 or 2. In some embodiments, a maximum spectrum efficiency of the table is equal to or smaller than a second threshold. In some embodiments, a combination of a modulation order and a code rate corresponding to the second threshold comprises (1) a modulation order of 4 and a code rate of 616/1024, (2) a modulation order of 6 and a code rate of 772/1024, or (3) a modulation order of 6 and a code rate of 873/1024.

Some examples of the disclosed techniques are further described in the following example embodiments.

Embodiment 1

Terminal devices with limited or reduced capabilities can select different CQI/MCS tables than the existing CQI/MSC tables. To enable appropriate CQI reporting and/or an MCS determination for a given device, the device type can facilitate the appropriate determination of CQI/MCS tables for the device. In some embodiments, the determination of a CQI/MCS table is based on a characteristic of a communication device indicating a set of limited capabilities supported by the communication device.

In some embodiments, a transport block corresponding to the CQI information is received with a transport block error probability or a block error ratio (BLER) not exceeding a threshold value (e.g., the BLER threshold) . In some embodiments, the determination of the threshold value (e.g., the BLER threshold) is based on a characteristic of a communication device indicating a set of limited capabilities supported by the communication device.

In some embodiments, a determination of a maximum CQI index is based on a characteristic of a communication device indicating a set of limited capabilities supported by the communication device.

In some embodiments, a determination of a maximum MCS index is based on a characteristic of a communication device indicating a set of limited capabilities supported by the communication device.

In some embodiments, the characteristic of the communication device comprises at least one of a device category of the communication device, a capability of the communication device; an operation mode of the communication device, or a combination thereof.

In some embodiments, the device category is determined by a set of UE capabilities.

In some embodiments, the UE capability includes a set of capability parameters. The capabilities parameters include at least one of:

a supported bandwidth;

a number of receiving and/or transmitting antennas;

a maximum Multiple-Input-Multiple-Output (MIMO) layer, a maximum rank, or a maximum number of ports;

a maximum number of Hybrid Automatic Repeat reQuest (HARQ) process;

a maximum modulation orders (in downlink and/or uplink directions) ;

a maximum code rate;

a maximum number of Control Resource Set (CORESETs) per downlink (DL) bandwidth part (BWP) or serving cell;

a maximum number of search space sets per DL BWP or serving cell;

a maximum number of monitored Physical Downlink Control Channel (PDCCH) candidates within a span;

a maximum number of non-overlapped Control Channel Element (CCE) within a span;

a maximum number of Downlink Control Information (DCI) sizes;

a processing timeline that includes at least one of Physical Downlink Shared Channel (PDSCH) decoding time or Physical Uplink Shared Channel (PUSCH) preparation time;

a maximum number of bits (e.g., downlink shared channel transport block bits) received within a period. In some embodiments, the period can be one of a transmission time interval (TTI) , a slot, a millisecond, or a second;

a maximum number of bits of a transport block (e.g., a downlink shared channel transport block) received within a period. In some embodiments, the period can be one of a TTI, a slot, a millisecond, or second;

a maximum number of transport blocks (e.g., downlink shared transport blocks) received within a period. In some embodiments, the period can be one of a TTI, a slot, a millisecond, or a second;

a maximum number of bits (e.g., uplink shared channel transport block bits) transmitted within a period. In some embodiments, the period can be one of a TTI, a slot, a millisecond, or a second;

a maximum number of bits of a transport block (e.g., an uplink shared channel transport block) transmitted within a period. In some embodiments, the period can be one of TTI, a slot, a millisecond, or second;

a maximum number of transport blocks (e.g., uplink shared channel transport blocks) transmitted within a period. In some embodiments, the period can be one of a TTI, a slot, a millisecond, or a second;

a maximum data rate (e.g., for PUSCH or PDSCH transmission in a serving cell or serving cell group) ;

a total number of soft channel bits (e.g., the total number of soft channel bits available for HARQ processing) ;

a buffer size (e.g., the total layer 2 buffer size defined as the sum of the number of bytes that the UE is capable of storing in the Radio Link Control (RLC) transmission windows, RLC reception, reordering windows, and/or in PDCP reordering windows for all radio bearers) ;

a duplex mode; and/or

a maximum number of repetition times of a physical channel or physical layer signal.

In some embodiments, the operation mode is associated with a scheme of co-existence with other terminal devices. In some embodiments, the operation mode of the communication device includes whether a terminal device operates in the standalone mode, in-band model, guard-band mode, or other operation modes.

In some embodiments, the duplex mode indicates whether a terminal device is capable of full-duplex communications and/or half-duplex communications. The half-duplex communications include communications in the half-duplex (HD) Frequency Division Duplex (FDD) mode.

In some embodiments, the capabilities parameters include at least the supported bandwidth and/or the number of receiving antennas.

In some embodiments, the capabilities parameters include at least the supported bandwidth and/or the number of transmitting antennas.

In some embodiments, the capabilities parameters include at least the supported bandwidth, the number of transmitting antennas, and/or the number of receiving antennas.

In some embodiments, the capabilities parameters include at least the supported bandwidth, and/or number of HARQ process.

In some embodiments, the capabilities parameters include at least the supported bandwidth, the number of transmitting antennas, and/or the maximum number of HARQ process.

In some embodiments, the capabilities parameters include at least the supported bandwidth, the number of receiving antennas, and/or the maximum number of monitored PDCCH candidates within a span.

In some embodiments, the capabilities parameters include at least the supported bandwidth, the maximum MIMO layer, and/or the maximum modulation order.

In some embodiments, the capabilities parameters include at least the supported bandwidth, the maximum MIMO layer, the maximum modulation order, and/or the maximum code rate.

In some embodiments, the capabilities parameters include at least the supported bandwidth, the number of receiving antennas, the maximum modulation order, and/or the supported half-duplex FDD operation type.

In some embodiments, the capabilities parameters include at least the supported bandwidth, the number of receiving antennas, and/or the maximum modulation order.

In some embodiments, the capabilities parameters include at least the supported bandwidth, the maximum data rate, and/or the supported half-duplex FDD operation type.

In some embodiments, the capabilities parameters include at least the supported bandwidth, the maximum data rate, and/or the maximum modulation order.

In some embodiments, the capabilities parameters include at least the supported bandwidth, the maximum data rate, the maximum modulation order, and/or the maximum number of MIMO layer.

In some embodiments, the capabilities parameters include at least the supported bandwidth, the maximum data rate, the maximum modulation order, the maximum number of MIMO layer, and/or supported half-duplex FDD operation type.

In some embodiments, the UE capabilities parameters include at least the supported bandwidth, the maximum number of MIMO layer, and/or the supported half-duplex FDD operation type.

In some embodiments, the capabilities parameters include at least the maximum number of bits received within a period, the maximum number of bits of a transport block received within a period, the maximum modulation order, and/or the total number of soft channel bits.

In some embodiments, the capabilities parameters include at least the maximum number of bits transmitted within a period, the maximum number of bits of a transport block transmitted within a period, and/or the maximum modulation order.

In some embodiments, the determination of the table is further based on predefined information.

In some embodiments, the determination of a maximum CQI index is based on predefined information.

In some embodiments, the determination of a maximum MCS index is based on predefined information.

In some embodiments, the determining of the threshold value (e.g., the BLER threshold) is based on predefined information.

In some embodiments, the predefined information comprises at least one of:

a higher layer signaling;

a Radio Network Temporary Identifier (RNTI) ;

a search space set type;

a DCI format;

a coverage enhancement operation;

a CSI type;

a resource allocation for a physical channel;

one or more resources for a random-access procedure, radio link recovery, or beam failure recovery procedures;

a subcarrier spacing; and/or

a frequency range.

In some embodiments, the coverage enhancement operation includes operation involving at least one of a coverage enhancement/recovery level, coverage enhancement/recovery mode, coverage level, coverage mode, a repetition transmission of a physical channel or a repetition transmission of a physical layer signal. In some embodiments, at least one of the coverage enhancement/recovery level, coverage enhancement/recovery mode, coverage level or coverage mode is associated with a maximum repetition times of a transmission on a physical channel or signal. In some embodiments, at least one of the coverage enhancement/recovery level, coverage enhancement/recovery mode, coverage level or coverage mode is associated with a repetition times of a transmission on a physical channel or signal. In some embodiments, the coverage enhancement operation can be differentiated by the range or maximum number of repetition times. In some embodiments, the physical channel includes at least one of PDCCH, PDSCH, the Physical Uplink Control Channel (PUCCH) , the Physical Uplink Shared Channel (PUSCH) , or the Physical Random Access Channel (PRACH) . In some embodiments, the physical layer signal includes at least one of Channel State Information Reference Signal (CSI-RS) or Sounding Reference Signal (SRS) . The repetition type includes repetition type A or repetition type B. In some embodiments, the repetition type A and repetition type B can be differentiated by the resource allocation of two consecutive physical channel transmissions. In some embodiments, for repetition type A, two consecutive physical channel transmissions are allocated in different slots. In some embodiments, for repetition type B, two consecutive physical channel transmissions can be allocated in different slots or same slot. In some embodiments, the repetition type A and repetition type B can be differentiated by the definition of the start of physical channel transmissions. In some embodiments, for repetition type A, the start of physical channel transmission is defined in relative to the start of a slot. In some embodiments, for repetition type B, the start of physical channel transmission is defined in relative to the PDCCH signaling (e.g., DCI) .

In some embodiments, a communication device can be configured with resources for random access procedure, radio link recovery, and/or beam failure recovery procedures. The resources can be predefined or indicated by RRC signaling or system information. In some embodiments, the resources can be associated with coverage enhancement operation. In some embodiments, the resources can include at least one of: a preamble sequence; a logical root sequence index; a preamble format; an association between Physical Random Access Channel (PRACH) occasion and/or Synchronization Signal (SS) /Physical Broadcast Channel (PBCH) ; a time or/and frequency resource for PRACH or preamble transmission; a PRACH configuration index; an information field in a random access response (RAR) (e.g., that is associated with or includes an indication of repetition times for message 3 or message 4) ; a repetition of message 3, message 4, or message B, where message B is PDSCH scheduled by DCI with Cyclic Redundancy Check (CRC) bits scrambled by MsgB-RNTI.

For example, a UE category can be defined for UEs with limited or reduced capabilities (e.g., devices with limited bandwidths, or devices with coverage enhancement) . In some embodiments, the UE category can be determined based on at least one of the following UE capabilities:

1. a: The device supports a bandwidth up to 20MHz for frequency range 1.

1. b: The device has one or two receiving antennas. The number of receiving antennas can be determined according the frequency range or the subcarrier spacing. For example, for frequency range 1, the number of receiving antennas of the device is 1; for frequency range 2, the number of receiving antennas of the device is 2.

1. c: The device has L maximum MIMO layers, L being a positive integer associated with a transmission direction. For example, for downlink transmissions, L = 4; for uplink transmissions, L = 2.

1. d: The device has a maximum modulation order of M, M being an integer indicating a corresponding MCS (e.g., Quadrature Phase Shift Keying, (QPSK) , 16-Quadrature Amplitude Modulation (16QAM) , etc. ) . The value of M can also be associated with transmission directions. For example, M = 6 (64 QAM) for downlink transmissions and M = 4 (16 QAM) for uplink transmissions.

1. e The device supports half-duplex Frequency Division Duplex (FDD) operation.

In some embodiments, the UE category can be determined based on at least the operation mode of the UE (e.g., the UE operates in one of the standalone mode, in-band mode, or guard-band mode) .

In some embodiments, the UE category is further determined based on the UE speed. In some embodiments, the UE speed can be measured based on the number of hand-overs a UE can perform within a predefined time period. In some embodiments, a UE is classified, based on its speed, into stationary UE, low-speed UE, medium-speed UE, or high-speed UE.

In some embodiments, after the UE reports its capabilities to the base station, the base station and UE have the same understanding of which category the UE belongs to.

In some embodiments, after the UE reports its capabilities to the base station, the base station can determine which category the UE belongs to by sending the category information to the UE via higher layer signaling (e.g., RRC signaling) .

In some embodiments, when a UE is categorized in the UE category for limited/reduced capability, a new CQI/MCS table or a new combination of CQI/MCS tables can be used.

Embodiment 2

This embodiment describes an example of a CQI table for communication devices with limited/reduced capabilities.

The NR technology has adopted several CQI tables that are suitable for eMBB and URLLC services. Table 1 shows a 4-bit CQI table suitable for URLLC services. Table 1 is also referred to as the URLLC CQI table in this document. To ensure ultra-reliability in data transmissions, lower code rates are used in the URLLC CQI table.

Table 1

The Long-Term Evolution (LTE) communication technology has also adopted CQI tables that are suitable for Machine-Type-Communication (MTC) . Table 2 shows a 4-bit CQI table suitable for MTC services. A plurality of subframes (e.g., indicated by repetition in Table 2) of CSI reference resource is assumed in the derivation of CQI in MTC communications. Also, the number of repetitions is associated with PDSCH repetition which enhances the coverage. Table 2 is also referred to as the MTC CQI table in this document.

Table 2

The CQI table (referred to as “the First CQI table” ) for devices with limited/reduced capabilities can be designed to include combinations of modulation orders and code rates based on the URLLC and MTC CQI tables.

For the UEs with limited/reduced capability, the code rates that the UEs can support may be limited to a relatively small range, similar to the URLLC scenarios. Also, the number of receiving or transmitting antenna for such UEs can be less than other types of UEs, which can impact the coverage. Repetitions of transmissions can be used to enhance/recover the coverage. For example, if the number of transmitting antenna is limited to a small number (e.g., 1) , the coverage can be improved by transmission repetitions similar to the MTC case.

The first CQI table

For example, all of the combinations of modulation orders and code rates in the CQI can be the same as some of the combinations in the URLLC CQI table or the MTC CQI table.

For example, a subset of combinations of modulation orders and code rates (e.g., C1 combinations, C1 being in a range of [1, 15] ) in the CQI can be the same as some of the combinations in the URLLC CQI table or the MTC CQI table. In this example, appropriate code rates and/or transmission repetitions can be offered to UEs with reduced/limited capabilities. In some embodiments, the threshold value of BLER for the CQI table can be set to 1/10.

In some embodiments, the C1 combinations can be determined based on a constraint on the spectrum efficiency. For example, the lowest spectrum efficiency of the C1 combinations is constrained to be equal to or greater than a first threshold. The combination corresponding to the first threshold can be 2×30/1024, 2×40/1024, or 2×50/1024. The highest spectrum efficiency of the C1 combinations is constrained to be equal to or smaller than a second threshold. The combination corresponding to second threshold can be 4×616/1024, 6×772/1024, or 6×873/1024. In some embodiments, the spectrum efficiencies of the C1 combinations of modulation order and code rate are the highest in the CQI table.

In some embodiments, the code rates of the C1 combinations do not exceed a third threshold. In some embodiments, the third threshold is associated with a selection of a Low-density Parity Check Code (LPDC) base graph. For example, the threshold value is R+Δ, wherein R is a code rate associated with the selection of a LPDC base graph, and wherein -1/8 ≤ Δ ≤ 1/8. For example, R=0.67. Currently, there are two base graphs (i.e., base grap 1 and base graph 2) defined in the 3GPP standard. Wherein the encoding and decoding operation with base graph 2 have lower complexity. The selection of LDPC base graph is based on payload size of a transport block and the code rate. When payload size is no larger than 3824 and code rate is no larger than 0.67, LDPC base graph 2 is used. In some embodiments, the code rate of a transport block is restricted to the third threshold such that only LDPC base graph 2 is used.

In some embodiments, the maximum modulation order does not exceed a fourth threshold. For example, the fourth threshold can be 4 or 2. That is, the limited/reduced capability devices are not required to support a high modulation order (e.g., 64 QAM) . In some embodiments, the reported modulation order does not exceed a fourth threshold (e.g., 4 or 2) .

In some embodiments, the C1 combinations include CQI indices 1-11 of the URLLC CQI table or CQI indices 1-12 of the MTC CQI table. In some embodiments, the code rate can be higher because ultra-reliability is not necessarily needed. Correspondingly, the C1 combinations include CQI indices 2-11 or 3-15 of the URLLC CQI table. In some embodiments, the C1 combinations can include CQI indices 2-12 of the MTC CQI table.

In some embodiments, at least some of the C1 combinations can be jointly coded or associated with repetition information for transmission or a resource block of CSI reference resource.

In some embodiments, the repetition information for transmission includes at least one of: a number of repetitions of a physical channel or signal transmission, the maximum number of repetitions of a physical channel or signal transmission, a repetition type of a physical channel or signal transmission, or a coverage enhancement operation.

In some embodiments, a list of numbers of repetition is configured by higher layer signaling. The number of repetitions is further indicated by DCI.

In some embodiments, a resource allocated to the repetition of the downlink transmission collides with other resources. In some embodiments, either the base station or the UE can determine that the resource allocated to the repetition of the downlink transmission is invalid.

In some embodiments, a resource allocated to the repetition of the downlink transmission is invalid due to a condition being satisfied. In some embodiments, the resource is a symbol or a slot. In some embodiments, the condition comprises at least one of:

(1) a resource indicated as an uplink resource by configuration parameters. In some embodiments, configuration parameter includes tdd-UL-DL-ConfigurationCommon and/or tdd-UL-DL-ConfigurationDedicated. In 3GPP specification, the parameter tdd-UL-DL-ConfigurationCommon or tdd-UL-DL-ConfigurationDedicated is used to semi-statically configure the slot configuration;

(2) a resource occupied by SS/PBCH blocks. In some embodiments, SS/PBCH block is provided by ssb-PositionsInBurst in SIB1 or ssb-PositionsInBurst in ServingCellConfigCommon;

(3) a resource occupied by control resource set for Type-0 PDCCH search space set. In some embodiments, control resource set for Type-0 PDCCH search space set is indicated in pdcch-ConfigSIB1 in MIB or in PDCCH-ConfigCommon. In 3GPP specification, Type-0 PDCCH search space set is for DCI with CRC scrambled by SI-RNTI.

(4) a resource indicated as an uplink resource or a flexible resource by DCI message. In some embodiments, the DCI message includes DCI format 2_0. In 3GPP specification, the DCI format 2_0 is used to dynamically configure the slot configuration;

(5) a resource indicated as invalid by higher layer signaling;

(6) a resource which is a guard period of the HD-FDD operation;

(7) a resource occupied by zero power CSI-RS resource;

(8) a resource indicated as rate match pattern by higher layer signaling. In some embodiments, the PDSCH is not transmitted in resource indicated as rate matching pattern; or

(9) a predefined repetition type.

Embodiment 3

This embodiment describes an example of two or more CQI table for communication devices with limited/reduced capabilities. For example, the two CQI tables (referred to as “the Second CQI table” and “the Third CQI table” ) for devices with limited/reduced capabilities can be designed based on the combinations of modulation orders and code rates shown in the URLLC and MTC CQI tables.

The Second CQI table

In some embodiments, a subset of combinations of modulation orders and code rates (e.g., C2 combinations, C2being in a range of [1, 15] ) of the Second CQI table is the same as the combinations in the URLLC CQI table. For example, the lowest spectrum efficiency of the C2 combinations is constrained to be equal to or greater than a first threshold. The combination corresponding to the first threshold can be 2×30/1024, 2×40/1024, or 2×50/1024. The highest spectrum efficiency of the C2 combinations is constrained to be equal to or smaller than a second threshold. The combination corresponding to second threshold can be 4×616/1024, 6×772/1024, or 6×873/1024.

In some embodiments, the code rates of the C2 combinations do not exceed a third threshold. In some embodiments, the third threshold is associated with a selection of a Low-density Parity Check Code (LPDC) base graph. For example, the threshold value is R+Δ, wherein R is a code rate associated with the selection of a LPDC base graph, and wherein -1/8 ≤ Δ ≤ 1/8. For example, R=0.67.

In some embodiments, the C2 combinations include CQI indices 1-11 of the URLLC CQI table. In some embodiments, the code rate can be higher because ultra-reliability is not necessarily needed. Correspondingly, the C2 combinations include CQI indices 2-11 or 3-15 of the URLLC CQI table.

The Third CQI table

In some embodiments, a subset of combinations of modulation orders and code rates (e.g., C3 combinations, C3 being in a range of [1, 15] ) of the Second CQI table is the same as the combinations in the MTC CQI table. For example, the lowest spectrum efficiency of the C3 combinations is constrained to be equal to or greater than a first threshold. The combination corresponding to the first threshold can be 2×30/1024, 2×40/1024, or 2×50/1024. The highest spectrum efficiency of the C3 combinations is constrained to be equal to or smaller than a second threshold. The combination corresponding to second threshold can be 4×616/1024, 6×772/1024, or 6×873/1024.

In some embodiments, the code rates of the C3 combinations do not exceed a third threshold. In some embodiments, the third threshold is associated with a selection of a Low-density Parity Check Code (LPDC) base graph. For example, the threshold value is R+Δ, wherein R is a code rate associated with the selection of a LPDC base graph, and wherein -1/8 ≤Δ ≤ 1/8. For example, R=0.67.

In some embodiments, the C3 combinations include CQI indices 1-12 of the MTC CQI table. In some embodiments, the code rate can be higher because ultra-reliability is not necessarily needed. Correspondingly, the C3 combinations include CQI indices 2-12 of the MTC CQI table.

In some embodiments, at least some of the C3 combinations can be jointly coded or associated with repetition information for transmission or a resource block of CSI reference resource.

In some embodiments, a resource allocated to the repetition of the downlink transmission collides with other resources. In some embodiments, the resource allocated to the repetition of the downlink transmission is invalid.

In some embodiments, a resource allocated to the repetition of the downlink transmission is invalid due to a condition being satisfied. In some embodiment, the condition comprises at least one of: (1) a resource indicated as an uplink resource by configuration parameters. In some embodiments, configuration parameter is tdd-UL-DL-ConfigurationCommon or tdd-UL-DL-ConfigurationDedicated; (2) a resource occupied by SS/PBCH blocks. In some embodiments, SS/PBCH block is provided by ssb-PositionsInBurst in SIB1 or ssb-PositionsInBurst in ServingCellConfigCommon; (3) a resource occupied by control resource set (e.g., CORESET for Type-0 PDCCH search space set) . In some embodiments, CORESET0 is indicated in pdcch-ConfigSIB1 in MIB or in PDCCH-ConfigCommon; (4) a resource indicated as an uplink resource or a flexible resource by DCI message (e.g., DCI format 2_0) ; (5) a resource indicated as invalid by higher layer signaling; (6) a resource which is a guard period of the HD-FDD operation; (7) a resource occupied by zero power CSI-RS resource; (8) a resource indicated as rate match pattern by higher layer signaling; or (9) a predefined repetition type.

Selection between the tables

A terminal device having limited/reduced capabilities can select a CQI table to use among the multiple CQI tables available (e.g., the two CQI tables defined for reduced capabilities and/or existing CQI tables) .

In some embodiments, the selection of the CQI table can be determined based on one or more of the following criteria:

3.1 UE capability: For example, if the UE supports capability A, the Second CQI table is used; if the UE supports capability B, the Third CQI table is used. Alternatively, or in addition, if the UE supports capability C, one of the existing CQI tables can be used.

3.2 Higher layer signaling. In some embodiments, the base station can indicate, via higher layer signaling such as RRC signaling, the appropriate CQI table that the UE should use.

3.3 RNTI. In some embodiments, the selection of the CQI table can depend on the RNTI that scrambles the CRC bits of DCI.

3.4 Search space set type. In some embodiments, the selection of the CQI table can correspond to a search space set type. For example, the Second CQI table can correspond to a particular search space set that includes at least one of type-0 common search space (CSS) set, type-0a CSS, type-1 CSS, type-2 CSS, type-3 CSS. The search space can also be common search space set.

3.5 DCI signaling and/or DCI format. In some embodiments, the DCI format that triggers CSI reporting can also convey information regarding repetition information for transmission.

The criteria of CQI table selection can also include at least one of coverage enhancement operations, Channel State Information (CSI) type (e.g., wideband or sub-band reporting; periodic CSI, semi-persistent CSI, or aperiodic CSI) , resource allocations (e.g., time/frequency resources, frequency hopping, repetition times) , subcarrier spacing, frequency range.

In some embodiments, the criteria of CQI table selection includes at least the UE capability and/or the search space set type.

In some embodiments, the criteria of CQI table selection includes at least the UE capability, the higher layer signaling, the CSI type, and/or the resource allocation of physical channel/signal.

In some embodiments, the criteria of CQI table selection includes at least the UE capability, the higher layer signaling, the CSI type and/or the resource allocation of physical channel/signal.

In some embodiments, the criteria of CQI table selection includes at least the UE capability and/or the higher layer signaling.

In some embodiments, the criteria of CQI table selection includes at least the UE capability, the coverage enhancement level, the coverage level, the coverage recovery level, and/or the coverage enhancement type.

In some embodiments, the criteria of CQI table selection includes at least the UE capability, the higher layer signaling, the coverage enhancement level, the coverage level, the coverage recovery level, and/or the coverage enhancement type.

In some embodiments, the criteria of CQI table selection includes at least the higher layer signaling, and/or the CSI type.

In some embodiments, the criteria of CQI table selection includes at least the higher layer signaling, the CSI type, and/or the DCI format.

In some embodiments, the threshold value of BLER for the Second CQI table can be set to 1/10. In some embodiments, the threshold value of BLER for the Third CQI table can be set to 1/10.

Embodiment 4

In some embodiments, the UE capability can be sufficient to handle slightly higher code rates. For example, the First CQI table discussed in Embodiment 2 can be used in combination with another CQI table that includes combinations having higher code rates. For example, the lowest spectrum efficiency in the CQI table corresponds to a combination of QPSK and 78/2014. As another example, the highest spectrum efficiency in the CQI table corresponds to a combination of 64 QAM and 948/2014. In some embodiments, the threshold value of BLER for this CQI table can be set to 1/10.

Table 3 shows an example 4-bit CQI table that can be used in combination with the First CQI table.

Table 3

Table 4 shows another example 4-bit CQI table that can be used in combination with the First CQI table.

Table 4

Selection between the First CQI table and the other CQI table (e.g., as shown in Table 3 or Table 4) can follow the same criteria as described in Embodiment 3.

Embodiment 5

In some embodiments, a CQI table is selection from a CQI table group. In some embodiments, the CQI table group comprises a first CQI table group and a second CQI table group. In some embodiments, the first CQI table group includes the Second CQI table and/or the Third CQI table as discussed in Embodiment 3. In some embodiments, the second CQI table group includes the URLLC CQI table, the MTC CQI table, the CQI table as shown in Table 3, and/or the CQI table as shown in Table 4.

In some embodiments, the selection of the CQI table or table group can be based on same criteria as discussed in Embodiment 3.

Example 1

In existing 3GPP standard, a higher layer signaling cqi-Table in CSI-ReportConfig is used to determine the CQI table amongst a set of CQI tables. When additional CQI table (s) are introduced to facilitate transmission for UEs with limited/reduced capabilities, an additional higher layer signaling can used to assist the determination of CQI set and/or threshold value of BLER. In this example, the CQI table for CQI reporting and/or the threshold value of BLER is determined by at least a first higher layer signaling and/or a second higher layer signaling. The first higher layer signaling can have a higher priority than the second higher layer signaling. That is, information carried in the second higher layer signaling is only used when the first higher layer signaling is not configured.

For example, the first higher layer signaling can indicate that the first CQI table group (e.g., including the Second CQI table or the Third CQI table) is used for CQI reporting and the threshold value of BLER is 1/10. The UE can select a final CQI table between the Second CQI table and the Third CQI table based on criteria discussed in Embodiment 3.

As another example, the first higher layer signaling is not configured. The UE selects a final CQI table from the second CQI table group (including the URLLC CQI table, the MTC CQI table, the CQI table as shown in Table 3, and/or the CQI table as shown in Table 4) . A second higher layer signaling can be transmitted to carry a parameter to indicate which CQI table and/or BLER threshold should be used. For example, a parameter value of 2-1 indicates that the CQI table as shown in Table 3 should be used with a BLER criteria of 1/10; a parameter value of 2-2 indicates that the CQI table as shown in Table 4 should be used with a BLER criteria of 1/10; a parameter value of 2-3 indicates that the URLLC CQI table should be used with a BLER criteria of 1/10^5. In some embodiments, the parameter value can directly indicate the appropriate CQI table to use (e.g., “table1” , “table2, ” etc. ) .

In some embodiments, the first higher layer parameter is associated with at least one of: the UE category or coverage enhancement operation. For example, the first signaling can indicate the UE category.

Example 2

In this example, the CQI table for CQI reporting and/or the threshold value of BLER is determined by at least UE information and/or a higher layer signaling. In some embodiments, the UE information includes at least one of UE capability; operation mode; resources for random-access procedure, radio link recovery procedure, or beam failure recovery procedure.

For example, UE information can indicate the first CQI table group (e.g., including the Second CQI table or the Third CQI table) is used for CQI reporting with a corresponding BLER threshold. As another example the UE information can be used to determine a UE category that indicates whether the first CQI table group is used for reporting with a corresponding BLER threshold. These are discussed in further detail in Embodiment 1. The UE can select a final CQI table between the Second CQI table and the Third CQI table based on criteria discussed in Embodiment 3.

As another example, the UE capability can indicate that the second CQI table group is used for CQI reporting with a corresponding BLER threshold. The UE then proceeds to select a final CQI table from the second CQI table group (including the URLLC CQI table, the MTC CQI table, the CQI table as shown in Table 3, and/or the CQI table as shown in Table 4) . A higher layer signaling can be transmitted to carry a parameter to indicate which CQI table and/or BLER threshold should be used. For example, a parameter value of 2-1 indicates that the CQI table as shown in Table 3 should be used with a BLER criteria of 1/10; a parameter value of 2-2 indicates that the CQI table as shown in Table 4 should be used with a BLER criteria of 1/10; a parameter value of 2-3 indicates that the URLLC CQI table should be used with a BLER criteria of 1/10^5. In some embodiments, the parameter value can directly indicate the appropriate CQI table to use (e.g., “table1” , “table2, ” etc. ) .

Embodiment 6

Typically, for each CQI table there are two corresponding MCS tables: one for uplink transmissions with transform precoding operation, one for downlink transmissions and uplink transmissions without transform precoding operation. Table 5 shows an MCS table that corresponds to the URLLC CQI table. Table 5 is also referred to as the URLLC MCS table in this document.

Table 5 Example MCS Table

Table 6 shows another MSC table in which, for the same index value, the code rate is variable based on the modulation order. Table 6 is also referred to as the URLLC MCS table II in this document. In Table 6, q=1 if a higher layer parameter tp-pi2BPSK is configured, otherwise, q=2.

Table 6 Example MCS Table

To facilitate transmission for communication devices with reduced or limited capabilities, the MCS tables can also be defined.

The First MCS table

In some embodiments, one or more MCS tables can be defined based on the newly defined CQI tables for limited/reduced capability communication devices. For example, Table 7 shows an example of the First MCS table that corresponds to the MTC CQI table in Table 2.

Table 7 Example MCS Table

The Second MCS table

In some embodiments, one or more MCS tables can be defined based on the existing MCS tables for limited/reduced capability communication devices.

In some embodiments, a subset of combinations of modulation orders and code rates (e.g., M1 combinations, M1 being in a range of [1, 31] ) of the Second MCS table is the same as the combinations in the URLLC MSC table (as shown in Table 5) . In some embodiments, the Second MCS table can be used for downlink communications or uplink transmission without transform precoding operation.

In some embodiments, the lowest spectrum efficiency of the M1 combinations is constrained to be equal to or greater than a first threshold. In some embodiments, the combination corresponding to the first threshold can be 2×30/1024, 2×40/1024, or 2×50/1024. The highest spectrum efficiency of the M1 combinations is constrained to be equal to or smaller than a second threshold. The combination corresponding to second threshold can be 4×616/1024, 6×772/1024, or 6×873/1024.

The highest spectrum efficiency of the M1 combinations is constrained to be equal to or smaller than a second threshold. The combination corresponding to second threshold can be 4×616/1024, 6×772/1024, or 6×873/1024. In some embodiments, the spectrum efficiencies of the M1 combinations of modulation order and code rate are the highest in the MCS table.

In some embodiments, the code rates of the M1 combinations do not exceed a third threshold. In some embodiments, the third threshold is associated with a selection of a Low-density Parity Check Code (LPDC) base graph. For example, the threshold value is R+Δ, wherein R is a code rate associated with the selection of a LPDC base graph, and wherein -1/8 ≤ Δ ≤ 1/8. For example, R=0.67.

In some embodiments, the maximum modulation order can be the same as the First MCS table (e.g., up to 6) . In some embodiments, the maximum modulation order does not exceed a fourth threshold. For example, the fourth threshold can be 4 or 2. That is, the limited/reduced capability devices are not required to support a high modulation order (e.g., 64 QAM) . In some embodiments, the reported modulation order does not exceed a fourth threshold (e.g., 4 or 2) .

In some embodiments, the M1 combinations include MCS indices 1-20 of the URLLC MCS table. In some embodiments, the code rate can be higher because ultra-reliability is not necessarily needed. Correspondingly, the M1 combinations include MCS indices 3-20 or 3-28 of the URLLC MCS table.

In some embodiments, at least some of the M1 combinations can be jointly coded or associated with repetition information for transmission. In some embodiments, the repetition information for transmission includes at least one of: a number of repetitions of a physical channel or signal transmission, the maximum number of repetitions of a physical channel or signal transmission , a repetition type of a physical channel or signal transmission, or a coverage enhancement operation. In some embodiments, a resource allocated to the repetition of the downlink transmission is invalid due to a condition being satisfied. In some embodiments, the condition is the same with the condition in Embodiment 2.

The Third MCS table

In some embodiments, a subset of combinations of modulation orders and code rates (e.g., M2 combinations, M2 being in a range of [1, 31] ) of the Third MCS table is the same as the combinations in the URLLC MSC table II (as shown in Table 6) . The Third MCS table can be used for uplink communications with transform precoding operation. For example, the lowest spectrum efficiency of the M2 combinations is constrained to be equal to or greater than a first threshold. The combination corresponding to the first threshold can be q×30/1024, q×40/1024, or q×50/1024, wherein q=1 or 2. In some embodiments, the value of q is determined by higher layer signaling. The highest spectrum efficiency of the M2 combinations is constrained to be equal to or smaller than a second threshold. The combination corresponding to second threshold can be 4×616/1024, 6×772/1024, or 6×873/1024.

In some embodiments, the code rates of the M2 combinations do not exceed a third threshold. In some embodiments, the third threshold is associated with a selection of a Low-density Parity Check Code (LPDC) base graph. For example, the threshold value is R+Δ, wherein R is a code rate associated with the selection of a LPDC base graph, and wherein -1/8 ≤Δ ≤ 1/8. For example, R=0.67.

In some embodiments, the maximum modulation order can be the same as the First MCS table (e.g., up to 6) . In some embodiments, the maximum modulation order does not exceed a fourth threshold. For example, the fourth threshold can be 4 or 2. That is, the limited/reduced capability devices are not required to support a high modulation order (e.g., 64 QAM) . In some embodiments, the reported modulation order does not exceed a fourth threshold (e.g., 4 or 2) . In some embodiments, the minimum modulation order is equal to q. For example, q=1 or 2. In some embodiments, the value of q is determined by higher layer signaling.

In some embodiments, the M2 combinations include MCS indices 1-20 of the URLLC MCS table II. In some embodiments, the code rate can be higher because ultra-reliability is not necessarily needed. Correspondingly, the M2 combinations include MCS indices 3-20 or 3-28 of the URLLC MCS table II.

In some embodiments, at least some of the M2 combinations can be jointly coded or associated with repetition information for transmission. In some embodiments, the repetition information for transmission includes at least one of: a number of repetitions of a physical channel or signal transmission, the maximum number of repetitions of a physical channel or signal transmission , a repetition type of a physical channel or signal transmission, or a coverage enhancement operation. In some embodiments, a resource allocated to the repetition of the downlink transmission is invalid due to a condition being satisfied. In some embodiments, the condition is the same with the condition in Embodiment 2.

The Fourth MCS table

In some embodiments, one or more MCS tables can be defined based on the newly defined MCS tables (e.g., the First MCS table as shown in Table 7) for limited/reduced capability communication devices.

In some embodiments, a subset of combinations of modulation orders and code rates (e.g., M3 combinations, M3 being in a range of [1, 15] ) of the Fourth MCS table is the same as the combinations in the First MCS table. The Fourth MCS table can be used for downlink communications or uplink transmission without transform precoding operation. For example, the lowest spectrum efficiency of the M3 combinations is constrained to be equal to or greater than a first threshold. The combination corresponding to the first threshold can be 2×30/1024, 2×40/1024, or 2×50/1024. The highest spectrum efficiency of the M3 combinations is constrained to be equal to or smaller than a second threshold. The combination corresponding to second threshold can be 4×616/1024, 6×772/1024, or 6×873/1024.

In some embodiments, the code rates of the M3 combinations do not exceed a third threshold. In some embodiments, the third threshold is associated with a selection of a Low-density Parity Check Code (LPDC) base graph. For example, the threshold value is R+Δ, wherein R is a code rate associated with the selection of a LPDC base graph, and wherein -1/8 ≤Δ ≤ 1/8. For example, R=0.67.

In some embodiments, the M3 combinations include MCS indices 1-11 of the First MCS table. In some embodiments, at least some of the M3 combinations can be jointly coded or associated with repetition information for transmission. In some embodiments, the repetition information for transmission includes at least one of: a number of repetitions of a physical channel or signal transmission, the maximum number of repetitions of a physical channel or signal transmission , a repetition type of a physical channel or signal transmission, or a coverage enhancement operation. In some embodiments, a resource allocated to the repetition of the downlink transmission is invalid due to a condition being satisfied. In some embodiments, the condition is the same with the condition in Embodiment 2.

The Fifth MCS table

In some embodiments, a subset of combinations of modulation orders and code rates (e.g., M4 combinations, M4 being in a range of [1, 15] ) of the Fifth MCS table is the same as the combinations in the First MCS table. The Fifth MCS table can be used for uplink communications with transform precoding operation. For example, the lowest spectrum efficiency of the M4 combinations is constrained to be equal to or greater than a first threshold. The combination corresponding to the first threshold can be q×30/1024, q×40/1024, or q×50/1024, wherein q=1 or 2. The highest spectrum efficiency of the M4 combinations is constrained to be equal to or smaller than a second threshold. The combination corresponding to second threshold can be 4×616/1024, 6×772/1024, or 6×873/1024.

In some embodiments, the code rates of the M4 combinations do not exceed a third threshold. In some embodiments, the third threshold is associated with a selection of a Low-density Parity Check Code (LPDC) base graph. For example, the threshold value is R+Δ, wherein R is a code rate associated with the selection of a LPDC base graph, and wherein -1/8 ≤ Δ ≤ 1/8. For example, R=0.67.

In some embodiments, the M4 combinations include MCS indices 1-11 of the First MCS table. In some embodiments, at least some of the M4 combinations can be jointly coded or associated with repetition information for transmission. In some embodiments, the repetition information for transmission includes at least one of: a number of repetitions of a physical channel or signal transmission, the maximum number of repetitions of a physical channel or signal transmission , a repetition type of a physical channel or signal transmission, or a coverage enhancement operation. In some embodiments, a resource allocated to the repetition of the downlink transmission is invalid due to a condition being satisfied. In some embodiments, the condition is the same with the condition in Embodiment 2.

Selection between the tables

A terminal device having limited/reduced capabilities can select an MCS table to use among the multiple MCS tables available (e.g., one or more MCS table of the five MCS tables defined for reduced capabilities and/or existing MCS tables) .

In some embodiments, the selection of the MCS table can be determined based on one or more of the following criteria:

6.1 UE capability: For example, if the UE supports capability A, the Second MCS table is used; if the UE supports capability B, the Third MCS table is used. Alternatively, or in addition, if the UE supports capability C, one of the existing MCS tables can be used.

6.2 Higher layer signaling. In some embodiments, the base station can indicate, via higher layer signaling such as RRC signaling, the appropriate MCS table that the UE should use.

6.3 RNTI. In some embodiments, the selection of the MCS table can depend on the RNTI that scrambles the CRC bits of DCI.

6.4 Search space set type. In some embodiments, the selection of the MCS table can correspond to a search space set type. For example, the Second MCS table can correspond to a particular search space set that includes at least one of type-0 CSS, type-0a CSS, type-1 CSS, type-2 CSS, type-3 CSS. The search space can also be common search space set.

6.5 DCI signaling and/or DCI format. In some embodiments, the DCI format that conveys MCS and repetition information for transmission.

The criteria can also include at least one of whether transform precoding is supported, whether transform precoding is enabled, the transmission direction, coverage enhancement operations, resource allocations (e.g., time/frequency resources, frequency hopping, repetition times) , subcarrier spacing, frequency range, the CQI table used for CSI reporting.

In some embodiments, the selection of the MCS table can be determined based on at least one of: the transmission direction, whether transform precoding is enabled, a higher layer parameter, DCI, RNTI, or DCI format.

In some embodiments, the selection of the MCS table can be determined based on at least one of: a higher layer parameter, DCI or DCI format, search space set, RNTI, coverage enhancement operation, resource allocation, or the CQI table used for CQI reporting.

Embodiment 7

To reduce complexity on the UE side, the maximum CQI index of UE reporting and/or the indicated maximum MCS index can be constrained.

In some embodiments, a determination of a maximum CQI index is based on a characteristic of a communication device indicating a set of limited capabilities supported by the communication device. In some embodiments, a determination of a maximum MCS index is based on a characteristic of a communication device indicating a set of limited capabilities supported by the communication device.

In some embodiments, the characteristic of the communication device comprises at least one of a device category of the communication device, a capability of the communication device; an operation mode of the communication device, or a combination thereof. In some embodiments, the device category is determined by a set of UE capabilities. In some embodiments, the determination of device category is the same with Embodiment 1.

7.1 UE capability: In some embodiments, if a UE does not support a specific feature, UE is not required to report a CQI or be indicated with an MCS index with a modulation order lager than m, m being an integer. The feature can be a maximum modulation order of m.

In some embodiments, the feature is a maximum code rate. In some embodiments, the maximum code rate is associated with a selection of a Low-density Parity Check Code (LPDC) base graph. For example, the maximum code rate is R+Δ, wherein R is a code rate associated with the selection of a LPDC base graph, and wherein -1/8 ≤ Δ ≤ 1/8. For example, R=0.67. Currently, there are two base graphs (i.e., base graph 1 and base graph 2) defined in the 3GPP standard. Wherein the encoding and decoding operation with base graph 2 have lower complexity. The selection of LDPC base graph is based on payload size of a transport block and the code rate. When payload size is no larger than 3824 and code rate is no larger than 0.67, LDPC base graph 2 is used. In some embodiments, the code rate of a transport block is restricted to the threshold value such that only LDPC base graph 2 is used.

In some embodiments, the feature is associated with at least one of the maximum modulation order, the coverage enhancement operation, the maximum repetition times of a transmission, the number of repetition times of a transmission, or a repetition type.

7.2 Subcarrier spacing. In some embodiments, for a first subcarrier spacing, the UE is not required to report a CQI or be indicated with an MCS index with modulation order lager than m, m being a positive integer. For example, the first subcarrier spacing includes at least one of 60 kHz or 120 kHz.

7.3 Search space set type. In some embodiments, for a first search space set type, the UE is not required to report a CQI or be indicated with an MCS index with modulation order lager than m, m being a positive integer. For example, the first search space set type includes at least one of type-0 CSS, type-0a CSS, type-1 CSS, type-2 CSS, type-3 CSS. In an example, the first search space type is common search space.

7.4 Frequency range. In some embodiments, for a predefined frequency range, the UE is not required to report a CQI or be indicated with an MCS index with modulation order lager than m, m being a positive integer. For example, the predefined frequency range includes frequency range 2.

7.5 Higher layer signaling. In some embodiments, whether the UE is required to report a CQI or be indicated with an MCS index with modulation order larger than m, m being a positive integer, depends on one or more higher layer signaling messages.

7.6 DCI and/or DCI format. In some embodiments, a DCI signaling of a particular DCI format triggers the CQI reporting or indicates an MCS index

7.7 RNTI. In some embodiments, for a first RNTI type or first range of RNTI value, the UE is not required to report a CQI or be indicated with an MCS index with modulation order lager than m, m being a positive integer.

7.8 CSI type. The CSI type includes at least one of the wideband CSI, sub-band CSI. In some embodiments, the CSI type includes the CSI report quantity. In some embodiments, the CSI type includes the periodic CSI, semi-persistent CSI, or aperiodic CSI. In some embodiments, for a particular CSI type, the UE is not required to report a CQI or be indicated with an MCS index with modulation order lager than m, m being a positive integer.

7.9 Resource allocation. In some embodiments, based on the resource allocation (frequency hopping, repetition times in time/frequency domain, maximum repetition times in time/frequency domain) , the UE is not required to report a CQI or be indicated with an MCS index with modulation order lager than m, m being a positive integer.

Additional criteria can also include coverage enhancement operations and/or transmission directions.

FIG. 3 shows an example of a wireless communication system 300 where techniques in accordance with one or more embodiments of the present technology can be applied. A wireless communication system 1200 can include one or more base stations (BSs) 305a, 305b, one or

more wireless devices

310a, 310b, 310c, 310d, and a core network 325. A

base station

305a, 305b can provide wireless service to

wireless devices

310a, 310b, 310c and 310d in one or more wireless sectors. In some implementations, a

base station

305a, 305b includes directional antennas to produce two or more directional beams to provide wireless coverage in different sectors.

The core network 325 can communicate with one or

more base stations

305a, 305b. The core network 325 provides connectivity with other wireless communication systems and wired communication systems. The core network may include one or more service subscription databases to store information related to the subscribed

wireless devices

310a, 310b, 310c, and 310d. A first base station 305a can provide wireless service based on a first radio access technology, whereas a second base station 305b can provide wireless service based on a second radio access technology. The

base stations

305a and 305b may be co-located or may be separately installed in the field according to the deployment scenario. The

wireless devices

310a, 310b, 310c, and 310d can support multiple different radio access technologies. The techniques and embodiments described in the present document may be implemented by the base stations of wireless devices described in the present document.

FIG. 4 is a block diagram representation of a portion of a radio station in accordance with one or more embodiments of the present technology can be applied. A radio station 405 such as a base station or a wireless device (or wireless device) can include processor electronics 410 such as a microprocessor that implements one or more of the wireless techniques presented in this document. The radio station 405 can include transceiver electronics 415 to send and/or receive wireless signals over one or more communication interfaces such as antenna 420. The radio station 405 can include other communication interfaces for transmitting and receiving data. Radio station 405 can include one or more memories (not explicitly shown) configured to store information such as data and/or instructions. In some implementations, the processor electronics 410 can include at least a portion of the transceiver electronics 415. In some embodiments, at least some of the disclosed techniques, modules or functions are implemented using the radio station 405. In some embodiments, the radio station 405 may be configured to perform the methods described herein.

It will be appreciated that the present document discloses techniques that allows proper CQI reporting and MCS determination by communication devices with limited or reduced capabilities. The disclosed and other embodiments, modules and the functional operations described in this document can be implemented in digital electronic circuitry, or in computer software, firmware, or hardware, including the structures disclosed in this document and their structural equivalents, or in combinations of one or more of them. The disclosed and other embodiments can be implemented as one or more computer program products, i.e., one or more modules of computer program instructions encoded on a computer readable medium for execution by, or to control the operation of, data processing apparatus. The computer readable medium can be a machine-readable storage device, a machine-readable storage substrate, a memory device, a composition of matter effecting a machine-readable propagated signal, or a combination of one or more them. The term “data processing apparatus” encompasses all apparatus, devices, and machines for processing data, including by way of example a programmable processor, a computer, or multiple processors or computers. The apparatus can include, in addition to hardware, code that creates an execution environment for the computer program in question, e.g., code that constitutes processor firmware, a protocol stack, a database management system, an operating system, or a combination of one or more of them. A propagated signal is an artificially generated signal, e.g., a machine-generated electrical, optical, or electromagnetic signal, that is generated to encode information for transmission to suitable receiver apparatus.

A computer program (also known as a program, software, software application, script, or code) can be written in any form of programming language, including compiled or interpreted languages, and it can be deployed in any form, including as a stand-alone program or as a module, component, subroutine, or other unit suitable for use in a computing environment. A computer program does not necessarily correspond to a file in a file system. A program can be stored in a portion of a file that holds other programs or data (e.g., one or more scripts stored in a markup language document) , in a single file dedicated to the program in question, or in multiple coordinated files (e.g., files that store one or more modules, sub programs, or portions of code) . A computer program can be deployed to be executed on one computer or on multiple computers that are located at one site or distributed across multiple sites and interconnected by a communication network.

The processes and logic flows described in this document can be performed by one or more programmable processors executing one or more computer programs to perform functions by operating on input data and generating output. The processes and logic flows can also be performed by, and apparatus can also be implemented as, special purpose logic circuitry, e.g., an FPGA (field programmable gate array) or an ASIC (application specific integrated circuit) .

Processors suitable for the execution of a computer program include, by way of example, both general and special purpose microprocessors, and any one or more processors of any kind of digital computer. Generally, a processor will receive instructions and data from a read only memory or a random-access memory or both. The essential elements of a computer are a processor for performing instructions and one or more memory devices for storing instructions and data. Generally, a computer will also include, or be operatively coupled to receive data from or transfer data to, or both, one or more mass storage devices for storing data, e.g., magnetic, magneto optical disks, or optical disks. However, a computer need not have such devices. Computer readable media suitable for storing computer program instructions and data include all forms of non-volatile memory, media and memory devices, including by way of example semiconductor memory devices, e.g., EPROM, EEPROM, and flash memory devices; magnetic disks, e.g., internal hard disks or removable disks; magneto optical disks; and CD ROM and DVD-ROM disks. The processor and the memory can be supplemented by, or incorporated in, special purpose logic circuitry.

While this patent document contains many specifics, these should not be construed as limitations on the scope of any invention or of what may be claimed, but rather as descriptions of features that may be specific to particular embodiments of particular inventions. Certain features that are described in this patent document in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable subcombination. Moreover, although features may be described above as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination may be directed to a subcombination or variation of a subcombination.

Similarly, while operations are depicted in the drawings in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. Moreover, the separation of various system components in the embodiments described in this patent document should not be understood as requiring such separation in all embodiments.

Only a few implementations and examples are described, and other implementations, enhancements and variations can be made based on what is described and illustrated in this patent document.

Claims

A method for wireless communication, comprising:

determining, by a communication device, a table comprising one or more combinations of modulation orders and code rates based on a characteristic of the communication device indicating a set of limited capabilities supported by the communication device; and

performing, by the communication device, an operation with a network node based on the table.
The method of claim 1, wherein the table comprises a Channel Quality Indicator (CQI) table.
The method of claim 2, wherein performing the operation comprises:

reporting, by the communication device, CQI information based on the CQI table to a network node.
The method of claim 3, wherein a transport block corresponding to the CQI information is received with a transport block error probability not exceeding a threshold value.
The method of claim 1, wherein the table comprises a Modulation and Coding Scheme (MCS) table.
The method of claim 5, performing the operation comprises:

receiving, by the communication device, Modulation and Coding Scheme (MCS) information associated with the MCS table from the network node.
The method of claim 5, wherein performing the operation comprises:

performing an uplink transmission or a downlink reception with the network node based on the MCS table by the communication device.
The method of any of claim 1 to 7, wherein the characteristic of the communication device comprises at least one of: a device category of the communication device, a capability of the communication device; an operation mode of the communication device, or a combination thereof.
The method of claim 8, wherein the capability of the communication device comprises at least one of: a bandwidth supported by the communication device, a number of antennas of the communication device, a maximum number of Multiple-Input-Multiple-Output (MIMO) layers supported by the communication device, a maximum modulation order supported by the communication device, a maximum code rate supported by the communication device, a duplex mode supported by the communication device, or a combination thereof.
The method of any of claims 1 to 9, wherein the determining of the table is further based on predefined information.
The method of claim 10, wherein the predefined information comprises at least one of: a transmission direction, whether transform precoding is enabled, or a CQI table selected for CQI reporting.
The method of claim 10, wherein the predefined information comprises at least one of: a higher layer signaling; a Radio Network Temporary Identifier; a search space set type; a DCI format; a coverage enhancement operation; a Channel Station Information (CSI) type; a resource allocation for a physical channel; one or more resources for a random-access procedure; a subcarrier spacing; a frequency range; or a combination thereof.
The method of claim 12, wherein the coverage enhancement operation is associated with at least a repetition of a transmission on a downlink physical channel or an uplink physical channel.
The method of claim 13, comprising:

determining, by the communication device, a resource allocated to the repetition of the downlink transmission is invalid due to a condition being satisfied.
The method of claim 14, wherein the condition comprises at least one of (1) the resource is indicated as an uplink resource by a configuration parameter, (2) the resource is occupied by a synchronization signal or a physical broadcast channel, (3) the resource is occupied by a control resource set, (4) the resource is indicated as an uplink resource or a flexible resource by a downlink control information (DCI) message, or (5) the resource is indicated as invalid by a higher layer signaling message.
The method of claim 12, wherein the one or more resources for a random-access procedure comprise at least one of: a preamble sequence, a logical root sequence index, a preamble format, a time resource for the random-access procedure, a frequency resource for the random-access procedure, a configuration index for the random-access procedure, or a repetition of a random-access transmission.
The method of any of claims 1 to 16, comprising:

reporting, by the communication device, the characteristic of the communication device to the network node indicating a device category that the communication device belongs to.
The method of any of claims 1 to 17, wherein a minimum spectrum efficiency of the table is equal to or greater than a first threshold.
The method of claim 18, wherein a combination of a modulation order and a code rate corresponding to the first threshold comprises (1) a modulation order of q and a code rate of 30/1024, (2) a modulation order of q and a code rate of 40/1024, or (3) a modulation order of q and a code rate of 50/1024, wherein q=1 or 2.
The method of any of claims 1 to 19, wherein a maximum spectrum efficiency of the table is equal to or smaller than a second threshold.
The method of claim 20, wherein a combination of a modulation order and a code rate corresponding to the second threshold comprises (1) a modulation order of 4 and a code rate of 616/1024, (2) a modulation order of 6 and a code rate of 772/1024, or (3) a modulation order of 6 and a code rate of 873/1024.
The method of any of claims 1 to 21, wherein the code rates of the table are equal to or below a third threshold.
The method of claim 22, wherein the third threshold is associated with a selection of a Low-density Parity Check Code (LPDC) base graph.
The method of claim 22, wherein the third threshold comprises R + Δ, wherein R is a code rate associated with the selection of a LPDC base graph, and wherein -1/8 ≤ Δ ≤ 1/8.
The method of any of claims 1 to 24, wherein the modulation orders of the table are equal to or below a fourth threshold.
The method of any of claims 1 to 25, wherein a subset of the one or more combinations of the modulation orders and the code rates is same as combinations in another table.
The method of any of claims 1 to 26, wherein at least one of the one or more combinations of the modulation orders and the code rates is associated with repetition information for a transmission or a resource block of a Channel State Information (CSI) reference resource.
A method for wireless communication, comprising:

receiving, by a network node, a characteristic of a communication device indicating a set of limited capabilities supported by the communication device; and

performing, by the network node, an operation with the communication device based on a table determined according to the characteristic of the communication device.
The method of claim 28, wherein the table comprises a Channel Quality Indicator (CQI) table.
The method of claim 29, wherein performing the operation comprises:

receiving, by the network node, Channel Quality Indicator (CQI) information associated with the CQI table.
The method of claim 30, wherein a transport block corresponding to the CQI information is transmitted with a transport block error probability not exceeding a threshold value.
The method of claim 28, wherein the table comprises a Modulation and Coding Scheme (MCS) table.
The method of claim 32, wherein performing the operation comprises:

transmitting, by the network node, Modulation and Coding Scheme (MCS) information associated with the MCS table to the communication device.
The method of claim 32, wherein performing the operation comprises:

performing an uplink reception or a downlink transmission with the communication device based on the MCS table.
The method of any of claims 28 to 34, wherein the characteristic of the communication device comprises at least one of: a device category of the communication device, a capability of the communication device, an operation mode of the communication device, or a combination thereof.
The method of claim 35, wherein the capability of the communication device comprises at least one of: a bandwidth supported by the communication device, a number of antennas of the communication device, a maximum number of Multiple-Input-Multiple-Output (MIMO) layers supported by the communication device, a maximum modulation order supported by the communication device, a maximum code rate supported by the communication device, a duplex mode supported by of the communication device, or a combination thereof.
The method of any of claims 28 to 36, wherein the table is determined further based on predefined information.
The method of claim 37, wherein the predefined information comprises at least one of: a transmission direction, whether transform precoding is enabled, or a CQI table selected for CQI reporting.
The method of claim 37, wherein the predefined information comprises at least one of: a higher layer signaling; a Radio Network Temporary Identifier; a search space set type; a DCI format; a coverage enhancement operation; a Channel Station Information (CSI) type; a resource allocation for a physical channel; one or more resources for a random-access procedure; a subcarrier spacing; a frequency range; or a combination thereof.
The method of claim 39, wherein the coverage enhancement operation is associated with at least a repetition of a transmission on a downlink physical channel or an uplink physical channel.
The method of claim 40, wherein a resource allocated to the repetition of the downlink transmission is invalid due to a condition being satisfied.
The method of claim 41, wherein the condition comprises at least one of (1) the resource is indicated as an uplink resource by a configuration parameter, (2) the resource is occupied by a synchronization signal or a physical broadcast channel, (3) the resource is occupied by a control resource set, (4) the resource is indicated as an uplink resource or a flexible resource by a downlink control information (DCI) message, or (5) the resource is indicated as invalid by a higher layer signaling message.
The method of claim 39, wherein the one or more resources for a random-access procedure comprise at least one of: a preamble sequence, a logical root sequence index, a preamble format, a time resource for the random-access procedure, a frequency resource for the random-access procedure, a configuration index for the random-access procedure, or a repetition of a random-access transmission.
The method of any of claims 28 to 43, comprising:

receiving, by the network node, the characteristic of the communication device from the communication device indicating a device category that the communication device belongs to.
The method of any of claims 28 to 44, wherein a minimum spectrum efficiency of the table is equal to or greater than a first threshold.
The method of claim 45, wherein a combination of a modulation order and a code rate corresponding to the first threshold comprises (1) a modulation order of q and a code rate of 30/1024, (2) a modulation order of q and a code rate of 40/1024, or (3) a modulation order of q and a code rate of 50/1024, wherein q=1 or 2.
The method of any of claims 28 to 46, wherein a maximum spectrum efficiency of the table is equal to or smaller than a second threshold.
The method of claim 47, wherein a combination of a modulation order and a code rate corresponding to the second threshold comprises (1) a modulation order of 4 and a code rate of 616/1024, (2) a modulation order of 6 and a code rate of 772/1024, or (3) a modulation order of 6 and a code rate of 873/1024.
The method of any of claims 28 to 48, wherein the code rates of the table are equal to or below a third threshold.
The method of claim 49, wherein the third threshold is associated with a selection of a Low-density Parity Check Code (LPDC) base graph.
The method of claim 49, wherein the third threshold comprises R + Δ, wherein R is a code rate associated with the selection of a LPDC base graph, and wherein -1/8 ≤ Δ ≤ 1/8.
The method of any of claims 28 to 51, wherein the modulation orders of the table are equal to or below a fourth threshold.
The method of any of claims 28 to 52, wherein a subset of the one or more combinations of the modulation orders and the code rates is same as combinations in another table.
The method of any of claims 28 to 53, wherein at least one of the one or more combinations of the modulation orders and the code rates is associated with repetition information for a transmission or a resource block of a Channel State Information (CSI) reference resource.
A communication apparatus, comprising a processor configured to implement a method recited in any one or more of claims 1 to 54.
A computer program product having code stored thereon, the code, when executed by a processor, causing the processor to implement a method recited in any one or more of claims 1 to 54.