V2X frequency and time resource indication signaling

Abstract

The present invention provides systems, methods and circuits for performing sidelink communication. An example method indicates frequency resource reservation in sidelink control information (SCI). The method includes identifying a transport block (TB) for transmission to a UE; determining a total number of subchannels (N) in a resource pool for sidelink communication; SL ), the number of sub-channels of TB (L sub ), a first starting subchannel index x1 for the first retransmission of the TB, and a second starting subchannel index x2 for the second retransmission of the TB. The method includes: SL , L SUB , x1 and x2 to determine the frequency resource indication value (FRIV), where FRIV represents L sub , x1 and x2, the predetermined function for L sub The possible combinations of x1, x2 and FRIV generate unique values. FRIV is encoded in SCI and the SCI is transmitted to the UE.

Description

[0001] This application is a divisional application of invention patent application 202080004533.0, filed on February 12, 2020, and entitled “V2X Frequency and Time Resource Indication Signaling”. Background Art

[0002] Vehicle-to-everything (V2X) communications cover communications from vehicle-based communication devices to various entities, including infrastructure (e.g., traffic signals), other vehicle-based devices, pedestrian-based devices, and / or the power grid. It is believed that widespread implementation of V2X systems will increase road safety, traffic efficiency, and save energy. V2X is based on communication from one device to another, which is called sidelink communication. Sidelink communication is different from downlink communication (network access point (AP) to user equipment (UE)) and uplink communication (UE to AP). V2X communication relies on devices that are capable of sidelink communication with limited assistance from the network. BRIEF DESCRIPTION OF THE DRAWINGS

[0003] Some examples of circuits, devices and / or methods will be described below by way of example only.In this context, reference will be made to the accompanying drawings.

[0004] Figures 1A to 1C A simplified overview of unicast, multicast, and broadcast sidelink communications is shown respectively.

[0005] Figure 2 An example communication sequence for sidelink communications between a transmitting user equipment wireless communication device (UE) and a receiving (RX) UE is shown.

[0006] Figure 3 Example bit allocations for Sidelink Control Information (SCI) Phase 1 Format 1 are shown.

[0007] Figure 4 is a chart illustrating example frequency resource indication values ​​(FRIV) mapped to respective values ​​of a first retransmission start subchannel, a second retransmission subchannel, and a total number of subchannels in a resource pool according to the various aspects described.

[0008] Figure 5 A flow chart of an example method for indicating frequency resource reservation in SCI Phase 1 communications in accordance with various aspects described is shown.

[0009] Figure 6 A flow chart of an example method for indicating time resource reservation in SCI Phase 1 communications in accordance with various aspects described is shown.

[0010] Figure 7 A flow chart of an example method for determining a scrambling code initialization value for SCI stage 2 transmissions in accordance with various aspects described is shown.

[0011] Figure 8 A flow chart of an example method for determining a scrambling code initialization value for a transport block (TB) transmission in accordance with various aspects described is shown.

[0012] Fig. 9 A flow chart of an example method for determining frequency resource allocation in DCI communications in accordance with various aspects described is shown.

[0013] Fig.10 A flow chart of an example method for determining time resource allocation in DCI communications in accordance with various aspects described is shown.

[0014] Fig.11 A simplified block diagram of a user equipment wireless communication device is shown in accordance with various aspects described. DETAILED DESCRIPTION

[0015] The present disclosure is described with reference to the accompanying drawings. The accompanying drawings are not drawn to scale, and these drawings are provided only for illustrating the present disclosure. Several aspects of the present disclosure are described below with reference to example applications for illustration. Many specific details, relationships, and methods are set forth to provide an understanding of the present disclosure. The present disclosure is not limited by the order of the actions or events illustrated, because some actions can occur in different orders and / or simultaneously with other actions or events. In addition, not all illustrated actions or events are necessary to implement the methods according to the present disclosure.

[0016] Figures 1A to 1C 1 is a block diagram of a wireless communication network 100 in which wireless communication devices (e.g., user equipment (UE) devices) use unicast, multicast, and broadcast communications. Each device in the network includes vehicle-to-everything (V2X) circuitry 110, which includes one or more processors configured to perform various types of V2X communications. For the purposes of this specification, when a "device" is described as performing a function, it is understood that the processor in the V2X circuitry is performing the function. Fig.11 An example wireless communication device is shown in more detail in FIG.

[0017] In the wireless communication network, a transmitting (TX) device (e.g., device 101) attempting to transmit data to one or more receiving (RX) devices first determines the sidelink channel resources available for that purpose. Fig. 9 and Fig.10In the embodiment of the present invention, TX device 101 requests a sidelink channel resource from a network or manager device 100 that coordinates communications between devices in the network. Manager device 100 may be another UE device or a base station device (gNB, eNB, etc.). Manager device 100 provides downlink control information (DCI) and / or a grant configuration of a sidelink configuration to the TX device, which identifies a specific sidelink channel resource that the TX device uses to transmit data. The specific sidelink channel resource is selected from a resource pool allocated to the network.

[0018] Depending on whether the TX device is to perform unicast, multicast, or broadcast transmission of data, the TX device determines (e.g., via higher layer signaling) a layer 1 destination identifier (L1 destination ID) that uniquely identifies one or more channels between the TX device 101 and a specific RX device (unicast identifier), a group of RX devices (multicast identifier), or all RX devices (broadcast identifier) ​​in the wireless communication network. In one example, the channel identified by the L1 destination ID is a physical sidelink control channel (PSCCH).

[0019] In mode 2 (such as Figures 1A to 1C As shown), TX device 101 selects side link channel resources for transmitting data from a pre-allocated resource pool received in advance from a manager device, rather than receiving a designation or allocation of a specific side link communication resource from manager device 100.

[0020] exist Figure 1A In the unicast example of , the TX device 101 attempts to transmit data to the RX device 102 and does not transmit data to other devices. To enable this "direct" communication, the TX device 101 initiates communication with the RX device 102 using a unicast L1 destination ID for the device 102. The TX device 101 sends side link control information (SCI) using a PSCCH resource associated with the L1 destination ID for the RX device 102. The SCI indicates how the RX device 102 subsequently receives a transport block (TB) of data from the TX device 101. For example, the SCI includes a unicast L1 destination ID for the RX device 102 and identifies the frequency and time resources of the physical sidelink shared channel (PSSCH) that specifies the TB to be transmitted (and in some cases, retransmitted). The SCI may also indicate whether the RX device provides feedback, such as an ACK / NACK indication, to confirm the receipt of the TB or to communicate that the TB was not received. To this end, the SCI may include a hybrid automatic repeat request (HARQ) process identifier that uniquely identifies the TB for the RX device to use to provide feedback.

[0021] exist Figure 1BIn the multicast example of FIG. 1 , the TX device 101 attempts to transmit data to a group G that includes several devices 102, 103, 104, 105 (although there are only four devices in the group shown, there can be a different number in the group). The multicast L1 destination ID identifies the PSCCH channel for SCI that is monitored by the devices in group G. To enable multicast communication, the TX device 101 determines the L1 destination ID for group G. The TX device 101 sends the SCI using the PSCCH resources associated with the L1 destination ID for group G. The SCI instructs the devices in group G how to subsequently receive TBs from the device 101. For example, the SCI includes the multicast L1 destination ID for group G and identifies the frequency and time resources of the physical sidelink shared channel (PSSCH) that is specified to be used for transmission and retransmission (in some cases) of the TBs.

[0022] The SCI may indicate multicast option 1 or 2, which indicates whether and how the RX devices in group G provide feedback. In multicast option 1, when feedback is enabled, the only type of feedback provided by the RX device is NACK, and in some examples, when a particular RX device is out of the communication range specified in the SCI, the RX device does not provide any feedback. In multicast option 2, when feedback is enabled, the RX device provides both ACK / NACK feedback. The SCI may include a hybrid automatic repeat request (HARQ) process identifier that uniquely identifies the TB for the RX device to use to provide feedback.

[0023] exist Figure 1C In the broadcast example of , the TX device 101 attempts to transmit data to all devices in the network. The broadcast L1 destination ID identifies the PSCCH channel for SCI that is monitored by all devices in the network. To enable broadcast communications, the device 101 determines the broadcast L1 destination ID for the network. The TX device 101 sends the SCI using the PSCCH resources associated with the broadcast L1 destination ID for the network. The SCI instructs devices in the network how to subsequently receive data from the device 101. For example, the SCI includes the broadcast L1 destination ID and identifies the frequency and time resources of the physical sidelink shared channel (PSSCH) that specifies to be used for transmission and retransmission (in some cases) of TBs.

[0024] A two-stage SCI process is adopted in 5G New Radio, an example of which is shown in Figure 2 In Phase 1, the SCI is transmitted on the PSCCH using the polarization code that has been adopted for NR DCI in the network. The SCI Phase 1 information is encoded in a bit sequence and is initialized by adding the bit sequence (e.g., performing a modulo-2 addition) to the constant first scrambling code initialization value C configured by the TX device for each resource pool. initAt 210, the resulting bit sequence is mapped to the frequency and time resources of the PSCCH for the RX device and transmitted by the TX device.

[0025] like Figure 2 As shown, SCI stage 1 includes, in part, frequency / time resource reservation for transmission and optional retransmission of a TB. Sidelink communication in 5G NR supports reserving resources for up to two retransmissions of the same TB, and the number of reserved resources for retransmission is defined in SCI stage 1. In the illustrated example, the number of reserved resources for retransmission is 2. SCI stage 1 also indicates an SCI stage 2 format, which indicates whether the RX device provides feedback or what type of feedback is provided.

[0026] At 210, SCI phase 2 is transmitted on the PSSCH using a polarization code that has been adopted for a physical downlink control channel (PDCCH) in the network. The SCI phase 2 information is encoded in a bit sequence and is added to the bit sequence (e.g., by performing a modulo-2 addition) by the TX device using a second C init The generated pseudo-random scrambling sequence is combined to scramble. At 220, the resulting bit sequence is mapped to the frequency and time resources of the PSSCH and transmitted by the TX device. The SCI stage 2 format defines whether feedback is expected or what type of feedback is expected, and also includes, in part, the HARQ process ID, the regional ID of the TX device, and the communication range for determining whether to provide NACK feedback in multicast option 1.

[0027] At 210, the TX device also transmits the TB using the frequency / time resources allocated in SCI stage 1 at 210. The TB is transmitted on the PSSCH using an LDPC code that has been adopted for a physical downlink shared channel (PDSCH) in the network. The TB data is encoded in a bit sequence and is added to the bit sequence (e.g., by performing a modulo-2 addition) using a third C init At 230, the resulting bit sequence is mapped to the frequency and time resources of the PSSCH and transmitted by the TX device.

[0028] At 240, the RX device provides appropriate feedback ACK / NACK, NACK only, or no feedback according to the SCI stage 2 format. If multicast option 1 (NACK only) is indicated in the SCI stage 2 format, the RX device determines the approximate distance between the TX device and the RX device based on the region ID indicated in the SCI stage 2. The RX device compares the distance to the communication range also indicated in the SCI stage 2. If the distance is less than the communication range, the RX device appropriately provides NACK feedback. If the distance is greater than or equal to the communication range, the RX device does not provide any feedback.

[0029] At 250, the TX device retransmits SCI Phase 1 and Phase 2 and also the TB using the frequency / time resources reserved in SCI Phase 1 at 210. At 250, frequency / time resources for the second and third retransmissions of the TB are reserved in SCI Phase 1, and at 250, frequency / time resources for the first retransmission of the TB are allocated in SCI Phase 1. In one example, if the TX device receives an ACK at 240 or does not receive a NACK from the RX device (depending on the SCI Phase 2 format), the TX device will not retransmit the TB. In the illustrated example, the TX device retransmits the TB regardless of the received feedback. At 260, the RX device provides appropriate feedback ACK / NACK, only NACK, or no feedback (e.g., multicast option 1) according to the SCI Phase 2 format and optionally the distance between the TX device and the RX device.

[0030] At 270, the TX device retransmits SCI Phase 1 and Phase 2 and also the TB using the frequency / time resources reserved in SCI Phase 1 at 210. At 270, frequency / time resources for the third and fourth retransmissions of the TB are reserved in SCI Phase 1, and at 270, frequency / time resources for the second retransmission of the TB are allocated in SCI Phase 1. At 280, the RX device provides appropriate feedback ACK / NACK, NACK only, or no feedback (e.g., multicast option 1) according to the SCI Phase 2 format and optionally the distance between the TX device and the RX device.

[0031] While LTE V2X supports the use of up to two resources to transmit a transport block, NR V2X supports the use of up to three resources to transmit a transport block. In NR V2X, the preconfigurable variable maxNumResource (N max ) is used to indicate whether 1, 2, or 3 resources are used to transmit the TB. max = 2, the number of bits allocated for the "Frequency Resource Allocation" field in SCI Phase 1 Format 1 is Where N SL is the total number of subchannels in the resource pool. max =3, the number of bits allocated for the "Frequency Resource Allocation" field in SCI Phase 1 Format 1 is SL. When N max = 2, the number of bits allocated for the "Frequency Resource Allocation" field in SCI Phase 1 Format 1 is 5 bits, and when N max =3, the number of digits is 11.

[0032] Frequency resource indication value and time resource indication value

[0033] Figure 3 A schematic diagram of an example V2X SCI Phase 1 Format 1 ("SCI Format 0_1") bit allocation 300 is shown. The frequency resource allocation includes bits indicating a frequency resource indication value (FRIV), and the time resource allocation field includes bits indicating a time resource indication value (TRIV).

[0034] In one example, FRIV uniquely identifies the number of subchannels (L) in a resource for a TB (all resources for a TB have the same size). sub ), the index value of the first starting subchannel (x1) reserved for the first retransmission of the TB (if applicable) and the index value of the second subchannel (x2) reserved for the second retransmission of the TB (if applicable). Parameter L sub Can have a value between 1 and N SL The parameters x1 and x2 can each have an integer value between 0 and N. SL -L sub Integer value in the range. In one example, FRIV is L SUB , x1 and x2, so that the RX UE can determine the values ​​of these three parameters based on the integer value of FRIV. For example, FRIV is some predetermined (known to the RX UE) arbitrary L SUB , x1, and x2 are mapped to FRIV values.

[0035] The following are examples of functions that can be used to determine FRIV and TRIV. It should be understood that the functions listed are merely one way to describe a combination or relationship of input parameters that produces a desired result. These functions are not intended to be understood as limited to the mathematical formulas listed, but are intended to be broadly understood to include any function that generates an equivalent result using a combination or relationship of parameters expressed by the function.

[0036] In one example, the predetermined function for generating FRIV is for N SL , L SUB The possible combinations of x1, x2 and x1 generate a continuous set of FRIV values. This minimizes the number of bits required to transmit the FRIV. An example FRIV function is:

[0037]

[0038] Figure 4 A graph 400 is shown which records the function using Formula 1 with x2 first convention, x1 second convention and L sub The third agreement is for N max =3 and N SL =4 calculated FRIV value. It can be seen that N SL , LSUB The FRIV of the combination of x1, x2, and x1 is a set of consecutive integer values.

[0039] Variations of the function of Equation 1 can be used to generate FRIV. For example, x1 and x2 can be swapped to obtain:

[0040]

[0041] When x1 and x2 are between 1 and N SL +1-L sub This function applies when:

[0042]

[0043] Where x1 and x2 are swapped in the function of Equation 3, the function becomes:

[0044]

[0045] If FRIV starts at 1 instead of 0, the formula for Equation 1 becomes:

[0046]

[0047] The function of formula 2 becomes:

[0048]

[0049] The function of formula 3 becomes:

[0050]

[0051] The function of formula 4 becomes:

[0052]

[0053] When N max = 2, an example function for determining FRIV is as follows, where x1 is the index of the starting subchannel of the first retransmission and is between 0 and N SL-L sub In the range between:

[0054]

[0055] In one example, TRIV is an integer that uniquely identifies a combination of a resource reservation window size (S) for a TB (i.e., 32 time slots), a first time gap (Δt1) between a first time resource on which the TB is transmitted and a second time resource on which the TB is retransmitted for the first time, and a second time gap (Δt2) between the second time resource and a third time resource on which the TB is retransmitted for the second time. In one example, TRIV is the result of a predetermined function of S, Δt1, and Δt2, such that the RX UE can determine the values ​​of these three parameters based on the integer value of TRIV. As another example, TRIV is the result of some predetermined (known to the RX UE) arbitrary mapping of S, Δt1, and Δt2 to TRIV values.

[0056] In one example, the predetermined function for generating TRIV generates a continuous set of TRIV values ​​for possible combinations of S, Δt1, and Δt2. This minimizes the number of bits required to transmit the TRIV. An example TRIV function that follows the third resource timing first convention and the second resource timing second convention is:

[0057]

[0058] In the function of formula 10, if there is only one retransmission Δt1, its range is between 0 and S-1-Δt2. If there are two retransmissions, Δt1 is in the range between 1 and S-1-Δt2. Δt2 is in the range between 0 and s-2. This is because even if the retransmissions may overlap in the frequency resources, the retransmissions should not occur in the same time resource (e.g., time slot). Δt1=0 means that the second resource (for the first retransmission) is not reserved. Δt1>0 means that the second resource (for the first retransmission) is reserved. Δt2=0 means that the third resource (for the second retransmission) is not reserved. Δt2>0 means that the third resource (for the second retransmission) is reserved. It is assumed that if the third resource is reserved, the second resource is also reserved.

[0059] Another predetermined function for generating a TRIV that complies with the first convention for timing the second resource and the second convention for timing the third resource is:

[0060]

[0061] In the function of formula 11, Δt1 is in the range between 0 and S-1, and Δt2 is in the range between 0 and S-1-Δt1. This is because even if the retransmissions may overlap in the frequency resources, the retransmissions should not occur in the same time resource (e.g., time slot). Δt1=0 means that the second resource (for the first retransmission) is not reserved. Δt1>0 means that the second resource (for the first retransmission) is reserved. Δt2=0 means that the third resource (for the second retransmission) is not reserved. Δt2>0 means that the third resource (for the second retransmission) is reserved. It is assumed that if the third resource is reserved, the second resource is also reserved.

[0062] When N max = 2, Δt2 = 0, and the following function can be used to generate TRIV, where Δt1 is in the range of 1 to S-1:

[0063] TRIV=Δt1. Formula 12

[0064] In one example, the above function for generating FRIV and TRIV for SCI is also applied to the corresponding fields of DCI format 3_0, which is used by the network (e.g., gNB) to schedule sidelink transmission in mode 1. DCI format 3_0 includes fields "SCI format 0_1" for frequency resource allocation and time resource allocation.

[0065] Scrambling sequence initialization value

[0066] from Figure 2 Recall that we first use different scrambling code initialization values ​​C init SCI phase 1, SCI phase 2, and TB are scrambled. In one example, the scrambling sequence for SCI phase 2 uses an SCI phase 2 C based on at least a portion of a cyclic redundancy check (CRC) code for the PSCCH. init To support SCI Phase 2C init The resource pool allocated for sidelink communication is (pre)configured with a constant N having bits based on each resource pool. CONST_RP In one example, A is an integer between 0 and 31. As used below, PSCCH_CRC refers to the decimal representation of the PSCCH CRC code value. Used to determine the SCI Phase 2C used to generate a scrambling code sequence (e.g., a gold sequence) for scrambling SCI Phase 2. init An example function of can be expressed as:

[0067] C init =(N PSCCH_CRC *2 A +N CONST_RP )mod 2 31 . Formula 13

[0068] SCI Phase 2C for determining the scrambling sequence used to generate the scrambling sequence for SCI Phase 2 init An alternative function of can be expressed as follows, where N PSCCH_MSB_CRC Corresponding to the (31-A) most significant bits of the decimal representation of the PSCCH CRC code:

[0069] C init =(N PSCCH_MSB_CRC *2 A +N CONST_RP )mod 2 31 . Formula 14

[0070] SCI Phase 2C for determining the scrambling sequence used to generate the scrambling sequence for SCI Phase 2 init An alternative function of can be expressed as follows, where N PSCCH_LSB_CRC Corresponding to the (31-A) least significant bits of the decimal representation of the PSCCH CRC code:

[0071] C init =(N PSCCH_LSB_CRC *2 A +N CONST_RP )mod 2 31 . Formula 15

[0072] In one example, the scrambling sequence for the TB uses data C based on at least a portion of a cyclic redundancy check (CRC) code value for the PSCCH and / or at least a portion of a CRC code value for SCI phase 2. init In order to support the data C init Based on the determination of each resource pool, a constant N having A bits is (pre-)configured for the resource pool allocated for side link communication CONST_RP In one example, A is an integer between 0 and 31. As used below, SCI2_CRC refers to a decimal representation of the SCI Phase 2 CRC code value. Data C for determining a scrambling code sequence (e.g., a gold sequence) for scrambling a TB based on the SCI Phase 2 CRC code value init A function of can be expressed as:

[0073] C init =(N SCI2_CRC *2 A +N CONST_RP )mod 2 31 . Formula 15

[0074] Alternatively, the following example function may be used, where N SCI2_MSB_CRC Corresponding to the (31-A) most significant bits of the decimal representation of the SCI Phase 2 CRC code:

[0075] C init =(N SCI2_MSB_CRC *2 A +N CONST_RP )mod 2 31 . Formula 16

[0076] Alternatively, the following example function may be used, where N SCI2_LSB_CRC Corresponding to the (31-A) least significant bits of the decimal representation of the SCI Phase 2 CRC code:

[0077] C init =(N SCI2_LSB_CRC *2 A +N CONST_RP )mod 2 31 . Formula 17

[0078] Used to determine data C based on SCI phase 2 CRC code value and PSCCH CRC code value init An example function of can be expressed as follows, where N MIX_CRC Depends on the PSCCH CRC code (N PSCCH_CRC ) and SCI Phase 2 CRC code (N SCI2_CRC )Both:

[0079] C init =(N MIXCRC *2 A +N CONST_RP )mod 2 31 . Formula 18

[0080] In one example, N MIXCRC YesN SCI2_CRC and N PSCCH_CRC The result of the logical XOR operation between them.

[0081] In one example, N MIXCRC YesN SCI2_CRC The (31-A) most significant bits and N PSCCH_CRC The result of the logical XOR operation between the (31-A) most significant bits.

[0082] In one example, N MIXCRC YesN SCI2_CRC The (31-A) most significant bits and N PSCCH_CRC The result of the logical XOR operation between the (31-A) least significant bits.

[0083] In one example, N MIXCRC YesN SCI2_CRC The (31-A) least significant bits and N PSCCH_CRCThe result of the logical XOR operation between the (31-A) most significant bits.

[0084] In one example, N MIXCRC YesN SCI2_CRC The (31-A) least significant bits and N PSCCH_CRC The result of the logical XOR operation between the (31-A) least significant bits.

[0085] In one example, N MIXCRC YesN SCI2_CRC The (31-AB) least significant bits and N PSCCH_CRC The concatenation of the B least significant bits of , where B is an integer between 0 and 24.

[0086] In one example, N MIXCRC YesN SCI2_CRC The (31-AB) most significant bits and N PSCCH_CRC The concatenation of the B least significant bits of , where B is an integer between 0 and 24.

[0087] In one example, N MIXCRC YesN SCI2_CRC The (31-AB) most significant bits and N PSCCH_CRC The concatenation of the B most significant bits of , where B is an integer between 0 and 24.

[0088] In one example, N MIXCRC YesN SCI2_CRC The (31-AB) least significant bits and N PSCCH_CRC The concatenation of the B most significant bits of , where B is an integer between 0 and 24.

[0089] In one example, N MIXCRC YesN PSCCH_CRC The (31-AB) least significant bits and N SCI2_CRC The concatenation of the B least significant bits of , where B is an integer between 0 and 24.

[0090] In one example, N MIXCRC YesN PSCCH_CRC The (31-AB) most significant bits and N SCI2_CRC The concatenation of the B least significant bits of , where B is an integer between 0 and 24.

[0091] In one example, where N MIXCRC YesN PSCCH_CRC The (31-AB) most significant bits and N SCI2_CRC The concatenation of the B most significant bits of , where B is an integer between 0 and 24.

[0092] In one example, N MIXCRC YesN PSCCH_CRC The (31-AB) least significant bits and N SCI2_CRC The concatenation of the B most significant bits of , where B is an integer between 0 and 24.

[0093] Data C for determining a scrambling code sequence (eg, a gold sequence) for scrambling a TB based on a PSCCH CRC code value init A function of can be expressed as:

[0094] C int =(N PSCCH_CRC *2 A +N CONST_RP )mod 2 31 . Formula 19

[0095] To determine the data C init An alternative function of can be expressed as follows, where N PSCCH_MSB_CRC Corresponding to the (31-A) most significant bits of the decimal representation of the PSCCH CRC code:

[0096] C int =(N PSCCH_MSB_CRC *2 A +N CONST_RP )mod 2 31 . Formula 20

[0097] To determine the data C init An alternative function of can be expressed as follows, where N PSCCH_LSB_CRC Corresponding to the (31-A) least significant bits of the decimal representation of the PSCCH CRC code:

[0098] C int =(N PSCCH_LSB_CRC *2 A +N CONST_RP )mod 2 31 Formula 21

[0099] Below are several flow charts outlining example methods. In this specification and the appended claims, the use of the term "determine" in reference to some entities (e.g., parameters, variables, etc.) when describing method steps or functions is to be interpreted broadly. For example, "determine" is interpreted to cover communications such as receiving and parsing an encoded entity or value of an entity. "Determine" should be interpreted to cover accessing and reading a memory (e.g., a lookup table, a register, a device memory, a remote memory, etc.) that stores an entity or a value for an entity. "Determine" should be interpreted to cover calculating or deriving an entity or a value of an entity based on other quantities or entities. "Determine" should be interpreted to cover any way of inferring or identifying an entity or a value of an entity.

[0100] As used herein, the term "identify" when used with reference to an entity or a value of an entity is to be broadly interpreted to encompass any manner of determining an entity or a value of an entity. For example, the term "identify" is to be interpreted to encompass, for example, receiving and parsing communications encoding an entity or a value of an entity. The term "identify" should be interpreted to encompass accessing and reading a memory storing an entity or a value for an entity (e.g., a device queue, a lookup table, a register, a device memory, a remote memory, etc.).

[0101] As used herein, the term "encode" when used with reference to some entity or value of an entity is to be broadly interpreted to encompass any manner or technique for generating a data sequence or signal that communicates the entity to another component.

[0102] Figure 5 1 is a flow chart outlining an example method 500 for indicating frequency resource reservation in sidelink control information (SCI). The method 500 may be performed by a processor executing stored instructions and / or hardware components of a wireless communication device (such as a UE or an eNB / gNB). The method includes, at 510, identifying a transport block (TB) for transmission to the UE. At 520, the method includes determining a subchannel (N) in a resource pool for sidelink communication. SL At 530, the number of subchannels of the TB is determined (L sub ). The method includes determining a first starting subchannel index x1 for a first retransmission of the TB at 540, and determining a second starting subchannel index x2 for a second retransmission of the TB at 550. The method includes determining, at 560, based on N SL , L SUB , x1 and x2 to determine the frequency resource indication value (FRIV), where FRIV represents L sub , x1 and x2, the predetermined function for L sub Possible combinations of x1, x2 generate unique values. At 570, FRIV is encoded in the SCI, and at 580, the SCI is transmitted to the UE.

[0103] Figure 6is a flow chart outlining an example method 600 for indicating a time resource reservation in sidelink control information (SCI). The method 600 may be performed by a processor executing stored instructions and / or hardware components of a wireless communication device, such as a UE or an eNB / gNB. The method includes, at 610, identifying a transport block (TB) for transmission to the UE. The method includes, at 620, determining a resource reservation window size S in a resource pool for sidelink communication. At 630, determining a first time gap Δt1 between a first time resource on which the TB is transmitted and a second time resource on which the TB is retransmitted for the first time, and at 640, determining a second time gap Δt2 between the second time resource and a third time resource on which the TB is retransmitted for the second time. The method includes, at 650, determining a time resource indication value (TRIV) based on S, Δt1, and Δt2, wherein the TRIV represents a result of a predetermined function of S, Δt1, and Δt2, the predetermined function generating a unique value for possible combinations of S, Δt1, and Δt2. At 660, the TRIV is encoded in the SCI, and at 670, the SCI is transmitted to the UE.

[0104] Figure 7 7 is a flow chart outlining an example method 700 for determining a scrambling code initialization value for use in sidelink communications. The method 700 may be performed by a processor executing stored instructions and / or hardware components of a wireless communication device, such as a UE or an eNB / gNB. The method includes, at 710, identifying a transport block (TB) for transmission to a UE. At 720, generating sidelink control information (SCI) stage 2 for transmitting the TB to the UE. At 730, encoding the SCI stage 2 in a first bit sequence. The method includes, at 740, determining an SCI stage 2 scrambling code initialization value (C SCI) based on at least a portion of a physical sidelink control channel (PSCCH) cyclic redundancy check (CRC) code. init ). The method includes at 750, based on SCI stage 2C init At 760, the first bit sequence is combined with the scrambling sequence to generate a scrambled sequence of SCI bits, and the scrambled sequence of SCI bits is mapped to a frequency and time resource of a physical sidelink shared channel (PSSCH) at 770. The method includes, at 780, transmitting the scrambled sequence of SCI bits to a UE using the frequency and time resources.

[0105] Figure 88 is a flow chart outlining an example method 800 for determining a scrambling code initialization value for use in sidelink communications. The method 800 may be performed by a processor executing stored instructions and / or hardware components of a wireless communication device, such as a UE or an eNB / gNB. The method includes, at 810, identifying a transport block (TB) for transmission to the UE. At 820, encoding the TB in a first bit sequence. The method includes, at 830, determining a sidelink data scrambling code initialization value (C SCC) based on at least a portion of a sidelink control information (SCI) stage 2 cyclic redundancy check (CRC) code. init ). The method includes, at 840, based on the data C init At 850, the first bit sequence is combined with the scrambling sequence to generate a scrambled sequence of data bits, and the scrambled sequence of data bits is mapped to frequency and time resources of a physical sidelink shared channel (PSSCH) at 860. The method includes, at 870, transmitting the scrambled sequence of data bits to the UE using the frequency and time resources.

[0106] Fig. 9 9 is a flow chart outlining an example method 900 for determining frequency resources for sidelink communication. The method 900 may be performed by a processor executing stored instructions and / or hardware components of a wireless communication device, such as a UE operating in sidelink communication mode 1. The method 900 includes, at 910, receiving, with a first UE, downlink control information (DCI) for transmitting a transport block (TB) to a second UE. At 920, identifying a frequency resource indication value (FRIV) in the DCI. The method includes, at 930, determining, based on the FRIV: a number of subchannels (L sub ); a first starting subchannel index x1 for the first retransmission of the TB; and a second starting subchannel index x2 for the second retransmission of the TB. FRIV represents L sub , x1 and x2, the predetermined function for L sub The possible combinations of x1, x2 and x4 generate unique values. At 940, the method includes transmitting the TB to the second UE using the frequency resources identified in the FRIV.

[0107] Fig.101 is a flow chart outlining an example method 1000 for determining time resources for sidelink communication. The method 1000 may be performed by a processor executing stored instructions and / or hardware components of a wireless communication device, such as a UE operating in sidelink communication mode 1. The method 1000 includes, at 1010, receiving, with a first UE, downlink control information (DCI) for transmitting a transport block (TB) to a second UE. At 1020, identifying a time resource indication value (TRIV) in the DCI. The method includes, at 1030, determining, based on the TRIV, a resource reservation window size S in a resource pool for sidelink communication; a first time gap Δt1 between a first time resource on which the TB is transmitted and a second time resource on which the TB is retransmitted for the first time; and a second time gap Δt2 between the second time resource and a third time resource on which the TB is retransmitted for the second time. The TRIV represents the result of a predetermined function of S, Δt1, and Δt2, the predetermined function generating unique values ​​for possible combinations of S, Δt1, and Δt2. At 1040, the method includes transmitting the TB to the second UE using the time resources identified in the FRIV.

[0108] As discussed in various aspects above, using FRIV and / or TRIV to indicate resource reservation is an effective way to reserve resources for sidelink communications.

[0109] See also Fig.11 , which shows a block diagram of a user equipment wireless communication device (UE) configured to perform sidelink communication according to various aspects described herein. The UE device 1100 includes: one or more processors 1110 (e.g., one or more baseband processors), the one or more processors including processing circuits and associated interfaces; transceiver circuits 1120 (e.g., including RF circuits, the RF circuits may include transmitter circuits (e.g., associated with one or more transmit chains) and / or receiver circuits (e.g., associated with one or more receive chains), the transmitter circuits and / or receiver circuits may use common circuit elements, different circuit elements, or a combination thereof); and a memory 1130 (which may include any of a variety of storage media and may store instructions and / or data associated with one or more of the processors 1110 or the transceiver circuits 1120).

[0110] In various aspects discussed herein, signals and / or messages may be generated and output for transmission, and / or transmitted messages may be received and processed. Depending on the type of signal or message generated, the output for transmission (e.g., by processor 1110, processor 1110, etc.) may include one or more of the following operations: generating an associated set of bits encoding the content of the encoded signal or message, encoding (e.g., which may include adding a cyclic redundancy check (CRC) and / or encoding via turbo codes, low-density parity check (LDPC) codes, tail-biting convolutional codes (TBCC), polar codes, etc.), scrambling (e.g., based on a scrambling seed), modulation (e.g., via one of binary phase shift keying (BPSK), quadrature phase shift keying (QPSK), or some form of quadrature amplitude modulation (QAM), etc.), and / or resource mapping (e.g., mapping to a scheduled set of resources, mapping to a set of time and frequency resources authorized for uplink transmission, etc.). Depending on the type of signal or message received, processing (e.g., by processor 1110, etc.) may include one or more of the following operations: identifying physical resources associated with the signal / message, detecting the signal / message, resource element group deinterleaving, demodulating, descrambling and / or decoding.

[0111] Although these methods are shown above and described as a series of actions or events, it should be understood that the order of such actions or events illustrated is not interpreted as having a limiting meaning. For example, some actions can occur simultaneously with other actions or events other than those actions or events shown and / or described herein in different orders. In addition, all the actions shown may not be required to realize one or more aspects or embodiments disclosed herein. In addition, one or more actions in the actions shown herein can be carried out in one or more separate actions and / or stages. In some embodiments, the method shown above can be implemented in a computer-readable medium using instructions stored in a memory. Many other embodiments and variations are possible within the scope of the present disclosure protected by the claims.

[0112] The term "coupled" is used throughout the specification. The term can cover connections, communications, or signal paths that enable a functional relationship consistent with the description of the present disclosure. For example, if device A generates a signal to control device B to perform an action, then in the first example, device A is coupled to device B, or in the second example, if the intermediate component C does not substantially change the functional relationship between device A and device B so that device B is controlled by device A via the control signal generated by the device, then device A is coupled to device B through the intermediate component C.

[0113] It is understood that the use of personally identifiable information should be subject to privacy policies and practices that are generally recognized to meet or exceed industry or government requirements for maintaining user privacy. Specifically, personally identifiable information data should be managed and processed to minimize the risk of unintentional or unauthorized access or use, and the nature of the authorized use should be clearly stated to users.

[0114] Appendix A

[0115] 1 Introduction

[0116] The 16th version of the NR V2X specification [1] was approved in December 2019. There are still some remaining tasks for NR V2X identified in [2].

[0117] In this article, we discuss details about some of the remaining tasks identified, including TBS determination, initialization of the scrambling sequence generator for phase 1 SCI, phase 2 SCI, and data transmitted on the PSSCH, phase 2 SCI format, time and frequency resource indication in phase 1 SCI, and MCS table for sidelink data transmission.

[0118] 2 Discussions

[0119] 2.1TBS determination

[0120] In the NR Uu link, the transport block size (TBS) is determined by a formula or a lookup table. The selection from the formula or the lookup table is based on the median number of information bits. Specifically, if the median number is greater than 3824, the TBS is calculated by the formula, otherwise, the TBS is obtained from the lookup table.

[0121] The median number of information bits is equal to the product of the code rate, modulation order, number of layers, and the total number of resource elements (REs) used for data transmission. The total number of REs used for data transmission is calculated based on the number of REs used for data transmission per RB, assuming that the number of REs used for data transmission in each allocated data channel resource block (RB) is the same. Here, the overhead from DMRS, CSI-RS, and CORESET is reduced in the calculation.

[0122] In general, the TBS determination procedure in the NR Uu link can be reused for the NR V2X sidelink with some modifications in counting the number of REs used for sidelink data transmission. Considering the multiplexing of PSCCH and PSSCH, the assumption that the sidelink data transmission has the same number of REs in each PSSCH RB is not applicable. Specifically, PSCCH is included in some RBs but not in other RBs. Therefore, the total number of REs used for data transmission should not be calculated based on the number of REs used for data transmission per RB.

[0123] Instead, the total number of REs used for sidelink transmission in the time slot is first calculated. The number of sidelink data REs is then obtained by subtracting the overhead from the calculated number. Here, the total number of REs used for sidelink transmission in the time slot is equal to the product of the number of subchannels indicated in the SCI, the (pre-)configured subchannel size of each resource pool, and the number of sidelink symbols per time slot.

[0124] Observation 1 : In the multiplexing of PSCCH and PSSCH, it is inaccurate to calculate the total number of sidelink data REs on a per RB basis.

[0125] Proposal 1: In the sidelink TBS determination, the number of sidelink data REs is calculated by subtracting the overhead from the total number of REs used for sidelink transmission in the timeslot.

[0126] Overhead from DMRS, CSI-RS and CORESET are counted when determining the NR Uu link TBS. Similarly, overhead from PSSCH DMRS, CSI-RS and PSCCH should also be counted when determining the sidelink TBS. In addition, some additional overhead for the sidelink should be considered:

[0127] 1. GAP symbols: GAP symbols in the side link are not used for data transmission.

[0128] 2. AGC symbol: The AGC symbol is used for AGC training and is not applicable to data transmission.

[0129] 3. Phase 2 SCI: NR V2X supports Phase 2 SCI, which is carried in PSSCH. Since the sidelink data is rate matched on the Phase 2 SCI, the PSSCH resources used for the Phase 2 SCI should be deducted.

[0130] 4.PSFCH symbols: Support for PSFCH is TDM with PSCCH / PSSCH, and PSFCH uses the last symbol in the slot available for the sidelink.

[0131] Proposal 2: In the sidelink TBS determination, overhead from PSSCH DMRS, CSI-RS, PSCCH, gap symbols, AGC symbols, second stage SCI and PSFCH symbols should be counted.

[0132] NR V2X supports blind retransmission of TB. Due to different PSFCH overhead, the TBS calculated in the initial transmission may be different from the TBS calculated in the blind retransmission. PSFCH periodicity of 1, 2 or 4 slots is supported. For the case where the PSFCH periodicity is 2 or 4 slots, the PSFCH may occur in the slot used for the initial transmission instead of the slot used for the blind retransmission, or vice versa.

[0133] Agree[3] to apply the LDPC code used for Release 15 NR PDSCH to PSSCH. In NR PDSCH, two LDPC basis graphs are designed and the selection between these two LDPC basis graphs depends on the code rate and TBS. TBS mismatch between initial transmission and blind retransmission can lead to the selection of different LDPC basis graphs. Incorrect LDPC basis graph selection will lead to PSSCH decoding errors. Therefore, it is necessary to align the TBS calculation between initial transmission and blind retransmission by introducing a common model TBS for LDPC basis graph selection.

[0134] Specifically, for resource pools without PSFCH resources, PSFCH overhead is never counted in TBS determination. For resource pools with PSFCH periodicity of 1 slot, PSFCH overhead is always counted in TBS determination. For resource pools with PSFCH periodicity of 2 or 4 slots, whether PSFCH overhead is counted is determined by the (pre) configuration of the resource pool. This design closes the potential gap between initial transmission and blind retransmission, so that UEs receiving initial transmission or blind retransmission obtain the same TBS.

[0135] Proposal 3: In the sidelink TBS determination, the PSFCH overhead is not counted for resource pools without PSFCH resources; the PSFCH overhead is counted for resource pools with PSFCH periodicity of 1 time slot; whether the PSFCH overhead is counted by the (pre-) configuration of resource pools with PSFCH periodicity of 2 or 4 time slots.

[0136] 2.2 Initialization of scrambling sequence

[0137] In LTE V2X, the scrambling sequence used for PSCCH is a golden sequence initialized to a constant value of 510. This constant value ensures that every receiver UE can decode PSCCH. This is because LTE V2X supports sidelink broadcasting and the resource reservation information in PSCCH needs to be decoded by all Mode 4 UEs for their resource allocation operations.

[0138] In NR V2X, resource reservation information is contained in the first stage SCI carried on PSCCH. Since this information is required for resource allocation operations of all Mode 2 UEs, PSCCH needs to be decoded by all UEs. Therefore, as in LTE V2X, a constant initialization value should be used for the PSCCH scrambling sequence generator. This constant initialization value can be based on each resource pool.

[0139] Proposal 4 : The scrambling sequence used for the first stage SCI is the golden sequence with a constant initialization value.

[0140] Agree[4] to apply separate scrambling codes on the second stage SCI and PSSCH. Similar to the scrambling code sequence of PSCCH, the scrambling code sequence of the second stage SCI is the golden sequence. The initialization value of the golden sequence is based on the PSCCH CRC. This design facilitates early termination of the second stage SCI polar decoding in case of a miss detection of PSCCH. For example, the initialization value can be set to c init =n RNTI 2 15 +n const , where n const is a constant whose value is equal to the initialization value of the PSCCH scrambling sequence, n RNTI It is the 16LSB of PSCCH CRC.

[0141] Proposal 5 : The scrambling sequence used for the second stage SCI is a golden sequence with an initialization value that depends on the PSCCH CRC, e.g., c init =n RNTI 2 15 +n const , where n const is a constant whose value is equal to the initialization value of the PSCCH scrambling sequence, n RNTI It is the 16LSB of PSCCH CRC.

[0142] In addition, the scrambling sequence for PSSCH data is also a golden sequence with an initialization value that depends on both the first-stage SCI CRC and the second-stage SCI CRC. Note that a portion of the PSSCH data decoding information is contained in the second-stage SCI (e.g., source ID, destination ID, HARQ process number, etc.). A miss detection of the second-stage SCI will result in an unsuccessful decoding of the PSSCH data. In addition, due to the limited randomness contained in the second-stage SCI (and therefore its CRC), a portion of the first-stage SCI CRC can also be used in the initialization value of the PSSCH data scrambling sequence. For example, the initialization value can be set to c init =n RNTI 2 15 +n const, where n const is a constant whose value is equal to the initialization value of the PSCCH scrambling sequence, n RNTI It is the XOR of the 16LSBs of the first stage SCI CRC and the 16MSBs of the second stage SCI CRC.

[0143] Proposal 6: The scrambling sequence for data on the PSSCH is a golden sequence with an initialization value that depends on both the first-stage SCI CRC and the second-stage SCI CRC, e.g., c init =n RNTI 2 15 +n const , where n const is a constant whose value is equal to the initialization value of the PSCCH scrambling sequence, n RNTI It is the XOR of the 16MSBs of the first stage SCI CRC and the 16LSBs of the second stage SCI CRC.

[0144] 2.3 Second Phase SCI Format

[0145] A two-stage SCI design is adopted in NR V2X, where the first-stage SCI (or SCI format 0_1) contains time and frequency resource allocation, priority, DMRS mode, second-stage SCI format, beta offset indicator, number of DMRS ports, MCS and reserved bits. The second-stage SCI (or SCI format 0_2) contains HARQ process ID, NDI, RV, source ID, destination ID, CSI request, area ID and communication range requirement, where the last two fields are only used for multicast option 1. The details of the second-stage SCI format are still open.

[0146] In our view, not all fields in the Phase 2 SCI are used in each broadcast type and in both options for multicast. For example, the region ID and communication range requirements are only used for multicast option 1. Broadcast may not require a 16-bit destination ID. We summarize the estimated view sizes and applicability in the table below.

[0147] Table 1: Estimated second stage SCI payload sizes for broadcast types

[0148]

[0149] From the table, it appears that the Phase 2 SCI payload size for broadcast is smaller than that for unicast and multicast, while the Phase 2 SCI payload size for multicast option 1 is larger than that for other multicast types. Based on this observation, we propose to have three Phase 2 SCI formats, one for broadcast, one for unicast and multicast option 2, and one for multicast option 1.

[0150] Proposal 7: Three second stage SCI formats are defined for broadcast, unicast and multicast option 2, and multicast option 1 respectively.

[0151] The "Phase 2 SCI Format" field in the Phase 1 SCI shall be 2 bits to indicate one of the three Phase 2 SCI formats. The last code point of this field is reserved for future use.

[0152] Proposal 8: The size of the "Second Phase SCI Format" field in the First Phase SCI is 2 bits.

[0153] The working assumption of the present invention [4] is that for both multicast and unicast when PSFCH resources are (pre-)configured in a resource pool, the SCI explicitly indicates whether HARQ feedback is used for the corresponding PSSCH transmission. Dynamic disabling of HARQ feedback can be achieved by adding a single bit in the second stage SCI.

[0154] Since multicast option 1 already has a maximum payload size for the second stage SCI, it is not desirable to additionally increase its second stage SCI payload size to indicate the disabling of HARQ feedback. In fact, if HARQ feedback is disabled for multicast option 1, the fields for region ID and communication range requirement are not used. Therefore, we can reuse these fields to indicate that HARQ feedback is disabled for multicast option 1. One possible way is to add a candidate value to the communication range requirement set, such as 0 meters. Intuitively, a value of 0 for the communication range requirement in the second stage SCI means that any distance between the TX UE and the RX UE is beyond the communication range requirement, so no HARQ feedback is required.

[0155] Proposal 9: For unicast and multicast option 2, an additional bit is included in the second stage SCI to indicate whether HARQ feedback is disabled. For multicast option 1, the indication of disabling HARQ feedback is via setting the communication range requirement to 0 meters.

[0156] 2.4 Time and frequency resource indication in the first stage SCI

[0157] Agree[5] that up to N TBs can be reserved in a single SCI max = 3 resources. In other words, SCI signaling is designed to allow full flexibility in indicating up to N resources in both time and frequency positions within a window of 32 time slots. max = 3 resources [6]. The indication of the time resource is separated from the indication of the frequency resource. Joint coding of the time position of all reserved resources and joint coding of the frequency position of all reserved resources are supported. However, the details of the joint coding of the time position or the frequency position must be designed.

[0158] The time resource indication value shall include code points for reserving a single resource and 31 code points for reserving two resources. Let us denote the resource reservation window size by S=32, denote the time gap between the first resource and the second resource by Δt1, and denote the time gap between the second resource and the third resource by Δt2. By definition, Δt2=0, ..., S-2, where Δt2=0 indicates that the third resource is not reserved. For the case of Δt2=0,

[0159] Δt1=0, ..., S-1, where Δt1=0 indicates that the second resource is not reserved; for the case of Δt2>0, Δt1=1, ..., S-1-Δt2, where Δt1>0 means that the second resource is always reserved. Then, the time resource indication value is given by Given.

[0160] The time resource indication formula has two characteristics: 1) the obtained time resource indication value is continuous for all possible Δt1 and Δt2 values; 2) the formula is applicable to N max =2 and N max =3 for both. max =2, the time resource indication formula is reduced to Δt1 by simply setting Δt2=0.

[0161] Proposal 10 :Time resource indication value is determined by Given, where S=32 is the resource reservation window size, Δt1 is the time gap between the first resource and the second resource, and Δt2 is the time gap between the second resource and the third resource.

[0162] Δt2=0, ..., S-2, where Δt2=0 indicates that the third resource is not reserved.

[0163] For the case of Δt2=0, Δt1=0, ..., S-1, where Δt1=0 indicates that the second resource is not reserved.

[0164] For the case where Δt2>0, Δt1=1, ..., S-1-Δt2.

[0165] The number of reserved resources is determined by the time resource indicator value in the SCI. For a given number of reserved resources, the number of subchannels per resource and the starting subchannel index of the second and third resources (if indicated) are calculated by the frequency resource indicator value in the SCI.

[0166] Assume that the total number of subchannels in the resource pool is N sub , and the number of subchannels per resource is L sub , 1≤L sub ≤N sub .

[0167] 1. If only one resource is reserved in the SCI, the frequency resource indication value is L sub -1.

[0168] 2. If two resources are reserved in the SCI, the starting subchannel index of the second resource is x1, and x1=0, ..., N sub -L sub , then the frequency resource indication value is given by Given.

[0169] 3. If two resources are reserved in the SCI, where the starting subchannel index of the second resource is x1 and the starting subchannel index of the third resource is x2, and x1, x2 = 0, ..., N sub -L sub , then the frequency resource indication value is given by Given.

[0170] The frequency resource indication values ​​obtained from the above frequency resource indication formula are continuous over all possible x1 and x2 values.

[0171] Proposal 11 : If a resource is reserved in SCI, the frequency resource indication value is L sub -1; if two resources are reserved in the SCI, the frequency resource indication value is given by If three resources are reserved in the SCI, the frequency resource indication value is given by Given, where N sub is the total number of subchannels in the resource pool, L sub is the number of subchannels per reserved resource, x1 = 0, ..., N sub -L sub is the starting subchannel index of the second resource, and x2=0, ..., N sub -L sub is the starting subchannel index of the third resource.

[0172] 2.5MCS table

[0173] Agreed [4] to support all three MCS tables for Rel-15NR Uu CP-OFDM for NR V2X sidelink. Like the Uu link, support for the low spectral efficiency 64QAM MCS table in the sidelink is an optional UE feature. From the transmitter perspective, support for 256QAM is based on UE capabilities. From the receiver perspective, it is open whether support for 256QAM is mandatory or based on UE capabilities.

[0174] In Rel-15 NR Uu link [7], support for 256QAM is mandatory for PDSCH in FR1, but optional for PDSCH in FR2. This means that for UEs operating in FR2 on NR Uu link, support for 256QAM is optional from both the transmitter and receiver perspectives based on UE capabilities. In our view, it is natural to extend this UE capability to the NR V2X sidelink, i.e., support for 256QAM in FR2 is optional based on UE capabilities.

[0175] Since the NR V2X sidelink targets a common design for FR1 and FR2, it is preferred to support 256QAM from a receiver perspective in both FR1 and FR2 based on UE capabilities.

[0176] Proposal 12: From the receiver perspective, UE support for 256QAM is based on UE capabilities.

[0177] The 256QAM MCS table targets high throughput use cases under good channel conditions. In sidelink broadcast and multicast, it cannot be guaranteed that the channel from the transmitter UE to each receiver UE is in a good state at the same time. Therefore, the usage scenarios of the 256QAM MCS table are limited.

[0178] On the other hand, the main motivation for using the low spectral efficiency 64QAM MCS table is to achieve ultra-reliable transmission in one go. This is useful for URLLC use cases. For ultra-reliable transmission, the low spectral efficiency 64QAM MCS table is used together with the low spectral efficiency 64QAM CQI table. In the NR V2X sidelink, CQI reporting only supports sidelink unicast. This means that the use of the low spectral efficiency 64QAM MCS table is limited to sidelink unicast.

[0179] Furthermore, support for 256QAM is a UE capability. Exchange of UE capabilities is not possible for sidelink broadcast and many sidelink multicast scenarios. Therefore, supporting 256QAM MCS tables and low spectral efficiency MCS tables for sidelink broadcast and multicast is inefficient.

[0180] Observation 2 : The benefit of using 256QAM MCS table and the less spectrally efficient 64QAM MCS table in sidelink broadcast and multicast is unclear.

[0181] Since the resource pool is designed to support sidelink unicast, multicast and broadcast, the only MCS table applicable to all broadcast types is the legacy 64QAM MCS table. Therefore, it is preferred to set the 64QAM MCS table as the default MCS table for the NR V2X sidelink. The use of the 256QAM MCS table and the low spectral efficiency 64QAM MCS table is configured via PC5-RRC for sidelink unicast.

[0182] Proposal 13: The legacy 64QAM MCS table is the default MCS table for the NR V2X sidelink. The use of the 256QAM MCS table or the low spectral efficiency 64QAM MCS table is configured via PC5-RRC.

[0183] 3 Conclusion

[0184] In this article, we discuss the remaining details of the NR V2X physical layer architecture. Our proposal is as follows:

[0185] Proposal 1: In the sidelink TBS determination, the number of sidelink data REs is calculated by subtracting the overhead from the total number of REs used for sidelink transmission in the slot.

[0186] Proposal 2: In the sidelink TBS determination, overhead from PSSCH DMRS, CSI-RS, PSCCH, gap symbols, AGC symbols, second stage SCI and PSFCH symbols should be counted.

[0187] Proposal 3: In the sidelink TBS determination, the PSFCH overhead is not counted for resource pools without PSFCH resources; the PSFCH overhead is counted for resource pools with PSFCH periodicity of 1 time slot; whether the PSFCH overhead is counted by the (pre-) configuration of resource pools with PSFCH periodicity of 2 or 4 time slots.

[0188] Proposal 4 : The scrambling sequence used for the first stage SCI is the golden sequence with a constant initialization value.

[0189] Proposal 5 : The scrambling sequence used for the second stage SCI is a golden sequence with an initialization value that depends on the PSCCH CRC, e.g., c init =n RNTI 2 15 +n const , where n const is a constant whose value is equal to the initialization value of the PSCCH scrambling sequence, n RNTI It is the 16LSB of PSCCH CRC.

[0190] Proposal 6: The scrambling sequence for data on the PSSCH is a golden sequence with an initialization value that depends on both the first-stage SCI CRC and the second-stage SCI CRC, e.g., c init =n RNTI 2 15 +n const , where n const is a constant whose value is equal to the initialization value of the PSCCH scrambling sequence, n RNTI It is the XOR of the 16MSBs of the first stage SCI CRC and the 16LSBs of the second stage SCI CRC.

[0191] Proposal 7: Three second stage SCI formats are defined for broadcast, unicast and multicast option 2, and multicast option 1 respectively.

[0192] Proposal 8: The size of the "Second Phase SCI Format" field in the First Phase SCI is 2 bits.

[0193] Proposal 9: For unicast and multicast option 2, an additional bit is included in the second stage SCI to indicate whether HARQ feedback is disabled. For multicast option 1, the indication of disabling HARQ feedback is via setting the communication range requirement to 0 meters.

[0194] Proposal 10 :Time resource indication value is determined by Given, where S=32 is the resource reservation window size, Δt1 is the time gap between the first resource and the second resource, and Δt2 is the time gap between the second resource and the third resource.

[0195] Δt2=0, ..., S-2, where Δt2=0 indicates that the third resource is not reserved.

[0196] For the case of Δt2=0, Δt1=0, ..., S-1, where Δt1=0 indicates that the second resource is not reserved.

[0197] For the case where Δt2>0, Δt1=1, ..., S-1-Δt2.

[0198] Proposal 11 : If a resource is reserved in SCI, the frequency resource indication value is L sub -1; if two resources are reserved in the SCI, the frequency resource indication value is given by If three resources are reserved in the SCI, the frequency resource indication value is given by Given, where N sub is the total number of subchannels in the resource pool, Lsub is the number of subchannels per reserved resource, x1 = 0, ..., N sub -L sub is the starting subchannel index of the second resource, and x2=0, ..., N sub -L sub is the starting subchannel index of the third resource.

[0199] Proposal 12: From the receiver perspective, UE support for 256QAM is based on UE capabilities.

[0200] Proposal 13: The legacy 64QAM MCS table is the default MCS table for the NR V2X sidelink. The use of the 256QAM MCS table or the low spectral efficiency 64QAM MCS table is configured via PC5-RRC.

[0201] 4 References

[0202] [1]Chairman's Notes, 3GPP TSG RAN#86Meeting, Sitges, ES, Dec.2019.

[0203] [2]RP-193198, Task list for 5G V2X in RAN1#100, Sitges, ES, Dec.2019.

[0204] [3]Chairman's Notes, 3GPP TSG RAN1 WG1#96bis Meeting, Xi'an, China, Apr.2019.

[0205] [4]Chairman's Notes, 3GPP TSG RAN1 WG1#98bis Meeting, Chongqing, China, Oct.2019.

[0206] [5]3GPP email discussion on maximum number of reserved resources for a TB, [98b-NR-15], Oct.2019.

[0207] [6]Chairman's Notes, 3GPP TSG RAN1 WG1#99Meeting, Reno, USA, Nov.2019.

[0208] [7]3GPP TS38.822,NR user equipment(UE)feature list,v15.0.1,Jul.2019.

Claims

1. An apparatus for a first user equipment UE, comprising one or more processors, wherein the one or more processors are configured to cause the first UE to: identifying a transport block TB for transmission to a second UE; generating side link control information SCI stage 2 for transmitting the TB to a second UE; encoding said SCI stage 2 in a first bit sequence; Determine the SCI stage 2 scrambling code initialization value C based on at least a portion of the physical side link control channel PSCCH cyclic redundancy check CRC code init1 ; Based on the SCI stage 2 scrambling code initialization value C init1 To generate a scrambling sequence; combining the first bit sequence with the scrambling sequence to generate a scrambled sequence of SCI bits; Mapping the scrambling sequence of the SCI bit to the frequency and time resources of the physical side link shared channel PSSCH; transmitting the scrambled sequence of the SCI bits to the second UE using the frequency and time resources; wherein the one or more processors are configured to cause the first UE to further perform the following operations: encoding the data of the TB in a second bit sequence; Based on at least a portion of the PSCCH CRC code, at least a portion of the SCI phase 2 CRC code, and a resource pool constant N having A bits CONST_RP To determine the data scrambling code initialization value C init2 , where N CONST_RP is configured for the resource pool allocated for sidelink communication, and A is an integer between 0 and 31; Based on the data scrambling code initialization value C init2 generating a second scrambling code sequence; combining the second bit sequence with the second scrambling sequence to generate a scrambled sequence of data bits; Mapping the scrambling sequence of the data bits to the frequency and time resources of the physical side link shared channel PSSCH; as well as transmitting the scrambling sequence of data bits to the second UE using the frequency and time resources to which the scrambling sequence of data bits is mapped, The data scrambling code initialization value C init2 It is determined using the following function: C init2 =(N MIXCRC *2 A +N CONST_RP )to 2 31 in: N MIXCRC Depends on the PSCCH CRC code N PSCCH_CRC and the SCI stage 2 CRC code N SCI2_CRC both.

2. The device according to claim 1, wherein N MIXCRC Including N SCI2_CRC With N PSCCH_CRC The result of the logical XOR operation between them.

3. The device according to claim 1, wherein N MIXCRC Including N SCI2_CRC Between bits 0 and 31 and N PSCCH_CRC A concatenation between bits 0 and 24 of , and wherein the concatenation comprises one of: N SCI2_CRC The (31-AB) least significant bits and N PSCCH_CRC The concatenation of the B least significant bits of ; N SCI2_CRC The (31-AB) most significant bits and N PSCCH_CRC The concatenation of the B least significant bits of ; N SCI2_CRC The (31-AB) most significant bits and N PSCCH_CRC the concatenation of the B most significant bits of ; or N SCI2_CRC The (31-AB) least significant bits and N PSCCH_CRC The concatenation of the B most significant bits of ; Where B is an integer between 0 and 24.

4. A method for wireless communication, the method comprising: Identifying a transport block TB for transmission to the UE; Generate side link control information SCI stage 2 for transmitting the TB to the UE; encoding said SCI stage 2 in a first bit sequence; Determine the SCI stage 2 scrambling code initialization value C based on at least a portion of the physical side link control channel PSCCH cyclic redundancy check CRC code init1 ; Based on the SCI stage 2 scrambling code initialization value C init1 To generate a scrambling sequence; combining the first bit sequence with the scrambling sequence to generate a scrambled sequence of SCI bits; Mapping the scrambling sequence of the SCI bit to the frequency and time resources of the physical side link shared channel PSSCH; Transmitting the scrambled sequence of the SCI bits to the UE using the frequency and time resources; wherein the method further comprises: encoding the data of the TB in a second bit sequence; Based on at least a portion of the PSCCH CRC code, at least a portion of the SCI phase 2 CRC code, and a resource pool constant N having A bits CONST_RP To determine the data scrambling code initialization value C init2 , where N CONST_RP is configured for the resource pool allocated for sidelink communication, and A is an integer between 0 and 31; Based on the data scrambling code initialization value C init2 generating a second scrambling code sequence; combining the second bit sequence with the second scrambling sequence to generate a scrambled sequence of data bits; Mapping the scrambling sequence of the data bits to the frequency and time resources of the physical side link shared channel PSSCH; and transmitting the scrambling sequence of data bits to the UE using the frequency and time resources to which the scrambling sequence of data bits is mapped, The data scrambling code initialization value C init2 It is determined using the following function: C init2 =(N MIXCRC *2 A +N CONST_RP )to 2 31 in: N MIXCRC Depends on the PSCCH CRC code N PSCCH_CRC and the SCI stage 2 CRC code N SCI2_CRC both.

5. The method according to claim 4, wherein N MIXCRC Including N SCI2_CRC With N PSCCH_CRC The result of the logical XOR operation between them.

6. The method according to claim 4, wherein N MIXCRC Including N SCI2_CRC Between bits 0 and 31 and N PSCCH_CRC A concatenation between bits 0 and 24 of , and wherein the concatenation comprises one of: N SCI2_CRC The (31-AB) least significant bits and N PSCCH_CRC The concatenation of the B least significant bits of ; N SCI2_CRC The (31-AB) most significant bits and N PSCCH_CRC The concatenation of the B least significant bits of ; N SCI2_CRC The (31-AB) most significant bits and N PSCCH_CRC the concatenation of the B most significant bits of ; or N SCI2_CRC The (31-AB) least significant bits and N PSCCH_CRC The concatenation of the B most significant bits of ; Where B is an integer between 0 and 24.

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