lteDCIResourceAllocation

DCI message physical resource blocks allocation

Syntax

[prbset,nrbg,rbgsize] = lteDCIResourceAllocation(enbue,dcistr)

[prbset,nrbg,rbgsize] = lteDCIResourceAllocation(dcistr)

Description

[prbset,nrbg,rbgsize] = lteDCIResourceAllocation(enbue,dcistr) returns a matrix containing the zero-based physical resource block (PRB) indices prbset, the number of resource block groups nrbg, and the resource block group size rbgsize, for the specified DCI message settings structure enbue and DCI message structure dcistr.

TS 36.213 [1] specifies resource allocation types used for downlink, uplink and sidelink. For more information, see Resource Allocation Types.

If you specify DCI Format 0, Format 4, or Format 5 in dcistr.DCIFormat, the function sets the system bandwidth based on the number of uplink resource blocks, enbue.NULRB. If you do not specify enbue.NULRB, the function sets the system bandwidth based on the number of downlink resource blocks, enbue.NDLRB. For all other formats, the function first checks enbue.NDLRB for the number of resource blocks. For more information, see Specifying Number of Resource Blocks.

[prbset,nrbg,rbgsize] = lteDCIResourceAllocation(dcistr) returns outputs prbset, nrbg, and rbgsize as above, except the fields described in structure enbue must be present as part of dcistr.

Calling lteDCIResourceAllocation specifying the dcistr structure as the only input argument is not recommended because this signature will be removed in a future release.

Examples

Get Allocated PRB Indices for DCI Message

Allocate DCI resource and shows the allocation of the DCI resources.

Create a DCI message structure with a system bandwidth of 50 resource blocks and DCI Format 1A.

enb = struct('NDLRB',50);
dciStr = lteDCI(enb,struct('DCIFormat','Format1A','AllocationType',1));

Return allocated physical resource block indices, the number of resource block groups, and the resource block group size.

[prbSet, nrBg, rbgSize] = lteDCIResourceAllocation(enb,dciStr)

prbSet = 1x2 uint64 row vector

    0   27

nrBg = int32

17

rbgSize = int32

3

Display Uplink PRB Allocation Type 1

Display the PRB allocations associated with the sequence of subframes in a frame for DCI Format 0 and uplink resource allocation type 1.

Configure a type 1 uplink resource allocation (multi-cluster). TS 36.213, Section 8.1.2 describes the resource indication value (RIV) determination.

enbue = struct('NDLRB',50);
dcistr = lteDCI(enbue,struct('DCIFormat','Format0','AllocationType',1));
dcistr.Allocation.RIV = 1;

Display an image of the PRBs used in each slot of each subframe in a frame.

• Create a subframeslots matrix full of zeros. There are 20 slots per frame, specifically two slots per subframe and ten subframes per frame.

• Loop through assigning a PRB set of indices for each subframe. Also assign a value in subframeslots for each occupied PRB index.

subframeslots = zeros(enbue.NDLRB,20);
for i = 0:9
    enbue.NSubframe = i;
    prbSet = lteDCIResourceAllocation(enbue,dcistr);
    prbSet = repmat(prbSet,1,2/size(prbSet,2));
    for s = 1:2
        subframeslots(prbSet(:,s)+1,2*i+s) = 20+s*20;
    end
end
imagesc(subframeslots); 
axis xy;
xlabel('Subframe Slots'); 
ylabel('PRB Indices');

Observe from the image that the same set of PRB indices is used in each slot.

Display Uplink Hopping PRB Allocation

Display the PRB allocations associated with the sequence of subframes in a frame for an uplink resource allocation with hopping.

Configure a type 1 uplink resource allocation that has type 0 hopping and slot and subframe hopping.

enbue = struct('NDLRB',50,'NCellID',0);
dcistr = lteDCI(enbue,struct('DCIFormat','Format0','AllocationType',0,...
    'FreqHopping',1));
dcistr.Allocation.HoppingBits = 0;
dcistr.Allocation.RIV = 110;
enbue.PUSCHHopping = 'InterAndIntra';
enbue.MacTxNumber = 0;
enbue.NSubbands = 1;
enbue.PUSCHHoppingOffset = 10;

Display an image of the PRBs used in each slot of each subframe in a frame.

• Create a subframeslots matrix full of zeros. There are 20 slots per frame, specifically two slots per subframe and ten subframes per frame.

• Loop through assigning a PRB set of indices for each subframe. Also assign a value in subframeslots for each occupied PRB index.

subframeslots = zeros(enbue.NDLRB,20);
for i = 0:9
    enbue.NSubframe = i;
    prbSet = lteDCIResourceAllocation(enbue,dcistr);
    prbSet = repmat(prbSet,1,2/size(prbSet,2));
    for s = 1:2
        subframeslots(prbSet(:,s)+1,2*i+s) = 20+s*20;
    end
end
imagesc(subframeslots)
axis xy
xlabel('Subframe Slots')
ylabel('PRB Indices')

Observe from the image that the occupied PRB indices hops in odd and even slots.

Input Arguments

enbue — DCI message settings

structure

DCI message settings, specified as a structure. enbue can contain the following fields.

Parameter Field	Required or Optional	Values	Description
NDLRB	Required	Scalar integer from 6 to 110	Number of downlink resource blocks ($$N_{\text{RB}}^{\text{DL}}$$)
CellRefP	Optional	1, 2, 4	Number of cell-specific reference signal (CRS) antenna ports
DuplexMode	Optional	'FDD' (default), 'TDD'	Duplexing mode, specified as one of the following: 'FDD' — Frequency division duplex (default) 'TDD' — Time division duplex
The following parameters apply when dcistr.DCIFormat = 'Format0' or 'Format4'
NULRB	Required	Scalar integer from 6 to 110	Number of uplink resource blocks. ($$N_{\text{RB}}^{\text{UL}}$$)
The following parameters apply when dcistr.FreqHopping = 1
NCellID	Required	Integer from 0 to 503	Physical layer cell identity
NSubframe	Required	0 (default), nonnegative scalar integer	Subframe number
NFrame	Required	0 (default), nonnegative scalar integer	Frame number
PUSCHHopping	Optional	'Inter' (default), 'InterAndIntra'	Uplink subframe hopping mode
MacTxNumber	Optional	Scalar integer from 0 (default) to 27	Number of the current MAC (re-)transmission, CURRENT_TX_NB
NSubbands	Optional	1 (default), 2, 3, or 4	Number of subbands.
PUSCHHoppingOffset	Optional	Scalar integer from 0 (default) to 98	PUSCH hopping offset
The following parameters apply for DCI Format 5 (dcistr = 'Format5').
NULRB	Required	Scalar integer from 6 to 110	Number of uplink resource blocks. ($$N_{\text{RB}}^{\text{UL}}$$)
The following parameters apply for DCI Format 5 (dcistr = 'Format5') with frequency hopping (dcistr.FreqHopping = 1).
NSubframePSSCH	Required	Integer	Subframe number in PSSCH subframe pool
PSSCHHoppingParameter	Optional	Integer from 0 (default) to 510. All values ≥ 504 are set to 510.	PSSCH hopping parameter
NSubbands	Optional	1, 2, or 4	Number of subbands
PSSCHHoppingOffset	Optional	Integer from 0 (default) to 110	PSSCH hopping offset
PRBPool	Optional	Integer vector	PSSCH resource block pool (sidelink transmission mode 2). A vector of zero-based indices giving the PRBs in the pool. If absent or empty then the pool is assumed to be the full transmission bandwidth
The following parameters apply for DCI Format 5A (dcistr = 'Format5A').
PSSCHNSubchannels	Optional	Integer from 1 (default) to 110	Number of sub-channels in the V2X PSSCH resource pool
PSSCHSubchannelSize	Optional	Integer from 1 to 110. Default value is 4.	Number of PRB in each sub-channel
PSSCHSubchannelPRBStart	Optional	Integer from 0 (default) to 109	First PRB index associated with first sub-channel of the resource pool
PSSCHAdjacency	Optional	'On' (default), 'Off'	Whether PSCCH and PSSCH are transmitted in adjacent PRB

Data Types: struct

dcistr — DCI message structure

structure

DCI message structure, returned as a structure whose fields match those of the associated DCI format.

The field names associated with dcistr are dependent on the DCI format. The format is expected to be one of the formats generated by lteDCI. The LTE standard defines resource allocations types for downlink, uplink, and sidelink. For more information, see Resource Allocation Types

The following table details the DCI formats and accompanying dcistr parameter fields.

DCI Formats	dciout Fields	Size	Description
'Format0'	DCIFormat	-	'Format0'
	CIF	0 or 3 bits	Carrier indicator field
	FreqHopping	1 bit	PUSCH frequency hopping flag
	Allocation	Varies	Resource block assignment/allocation
	ModCoding	5 bits	Modulation, coding scheme, and redundancy version
	NewData	1 bit	New data indicator
	TPC	2 bits	PUSCH TPC command
	CShiftDMRS	3 bits	Cyclic shift for DM RS
	TDDIndex	2 bits	For TDD config 0, this field is the Uplink Index. For TDD config 1–6, this field is the Downlink Assignment Index. Not present for FDD.
	CSIRequest	1, 2, or 3 bits	CSI request
	SRSRequest	0 or 1 bit	SRS request. This field can only be present in DCI formats scheduling PUSCH which are mapped onto the UE specific search space given by the C-RNTI
	AllocationType	1 bit	Resource allocation type, only present if $$N_{\text{RB}}^{\text{UL}}$$≤$$N_{\text{RB}}^{\text{DL}}$$.
'Format1'	DCIFormat	-	'Format1'
	CIF	0 or 3 bits	Carrier indicator field
	AllocationType	1 bit	Resource allocation header: type 0, type 1. If downlink bandwidth is ≤10 PRBs there is no resource allocation header and resource allocation type 0 is assumed.
	Allocation	Varies	Resource block assignment/allocation
	ModCoding	5 bits	Modulation and coding scheme
	HARQNo	3 bits (FDD) 4 bits (TDD)	HARQ process number
	NewData	1 bit	New data indicator
	RV	2 bits	Redundancy version
	TPCPUCCH	2 bits	PUCCH TPC command
	TDDIndex	2 bits	For TDD config 0, this field is not used. For TDD config 1–6, this field is the Downlink Assignment Index. Not present for FDD.
	HARQACKResOffset	2 bits	HARQ-ACK resource offset. Present when this format is carried by EPDCCH. Not present when this format is carried by PDCCH
'Format1A'	DCIFormat	-	'Format1A'
	CIF	0 or 3 bits	Carrier indicator field
	AllocationType	1 bit	VRB assignment flag: 0 (localized), 1 (distributed)
	Allocation	Varies	Resource block assignment/allocation
	ModCoding	5 bits	Modulation and coding scheme
	HARQNo	3 bits (FDD) 4 bits (TDD)	HARQ process number
	NewData	1 bit	New data indicator
	RV	2 bits	Redundancy version
	TPCPUCCH	2 bits	PUCCH TPC command
	TDDIndex	2 bits	For TDD config 0, this field is not used. For TDD config 1–6, this field is the Downlink Assignment Index. Not present for FDD.
	SRSRequest	0 or 1 bit	SRS request. This field can only be present in DCI formats scheduling PUSCH which are mapped onto the UE specific search space given by the C-RNTI
	HARQACKResOffset	2 bits	HARQ-ACK resource offset. Present when this format is carried by EPDCCH. Not present when this format is carried by PDCCH
'Format1B'	DCIFormat	-	'Format1B'
	CIF	0 or 3 bits	Carrier indicator field
	AllocationType	1 bit	VRB assignment flag: 0 (localized), 1 (distributed)
	Allocation	Varies	Resource block assignment/allocation
	ModCoding	5 bits	Modulation and coding scheme
	HARQNo	3 bits (FDD) 4 bits (TDD)	HARQ process number
	NewData	1 bit	New data indicator
	RV	2 bits	Redundancy version
	TPCPUCCH	2 bits	PUCCH TPC command
	TDDIndex	2 bits	For TDD config 0, this field is not used. For TDD config 1–6, this field is the Downlink Assignment Index. Not present for FDD.
	TPMI	2 bits for two antennas 4 bits for four antennas	PMI information
	PMI	1 bit	PMI confirmation
	HARQACKResOffset	2 bits	HARQ-ACK resource offset. Present when this format is carried by EPDCCH. Not present when this format is carried by PDCCH
'Format1C'	DCIFormat	-	'Format1C'
	Allocation	Varies	Resource block assignment/allocation
	ModCoding	5 bits	Modulation and coding scheme
'Format1D'	DCIFormat	-	'Format1D'
	CIF	0 or 3 bits	Carrier indicator field
	AllocationType	1 bit	VRB assignment flag: 0 (localized), 1 (distributed)
	Allocation	Varies	Resource block assignment/allocation
	ModCoding	5 bits	Modulation and coding scheme
	HARQNo	3 bits (FDD) 4 bits (TDD)	HARQ process number
	NewData	1 bit	New data indicator
	RV	2 bits	Redundancy version
	TPCPUCCH	2 bits	PUCCH TPC command
	TDDIndex	2 bits	For TDD config 0, this field is not used. For TDD config 1–6, this field is the Downlink Assignment Index. Not present for FDD.
	TPMI	2 bits for two antennas 4 bits for four antennas	Precoding TPMI information
	DlPowerOffset	1 bit	Downlink power offset
	HARQACKResOffset	2 bits	HARQ-ACK resource offset. Present when this format is carried by EPDCCH. Not present when this format is carried by PDCCH
'Format2'	DCIFormat	-	'Format2'
	CIF	0 or 3 bits	Carrier indicator field
	AllocationType	1 bit	Resource allocation header: type 0, type 1. If downlink bandwidth is ≤10 PRBs there is no resource allocation header and resource allocation type 0 is assumed.
	Allocation	Varies	Resource block assignment/allocation
	TPCPUCCH	2 bits	PUCCH TPC command
	TDDIndex	2 bits	For TDD config 0, this field is not used. For TDD config 1–6, this field is the Downlink Assignment Index. Not present for FDD.
	HARQNo	3 bits (FDD) 4 bits (TDD)	HARQ process number
	SwapFlag	1 bit	Transport block to codeword swap flag
	ModCoding1	5 bits	Modulation and coding scheme for transport block 1
	NewData1	1 bit	New data indicator for transport block 1
	RV1	2 bits	Redundancy version for transport block 1
	ModCoding2	5 bits	Modulation and coding scheme for transport block 2
	NewData2	1 bit	New data indicator for transport block 2
	RV2	2 bits	Redundancy version for transport block 2
	PrecodingInfo	3 bits for two antennas 6 bits for four antennas	Precoding information
	HARQACKResOffset	2 bits	HARQ-ACK resource offset. Present when this format is carried by EPDCCH. Not present when this format is carried by PDCCH
'Format2A'	DCIFormat	-	'Format2A'
	CIF	0 or 3 bits	Carrier indicator field
	AllocationType	1 bit	Resource allocation header: type 0, type 1. If downlink bandwidth is ≤10 PRBs there is no resource allocation header and resource allocation type 0 is assumed.
	Allocation	Varies	Resource block assignment/allocation
	TPCPUCCH	2 bits	PUCCH TPC command
	TDDIndex	2 bits	For TDD config 0, this field is not used. For TDD config 1–6, this field is the Downlink Assignment Index. Not present for FDD.
	HARQNo	3 bits (FDD) 4 bits (TDD)	HARQ process number
	SwapFlag	1 bit	Transport block to codeword swap flag
	ModCoding1	5 bits	Modulation and coding scheme for transport block 1
	NewData1	1 bit	New data indicator for transport block 1
	RV1	2 bits	Redundancy version for transport block 1
	ModCoding2	5 bits	Modulation and coding scheme for transport block 2
	NewData2	1 bit	New data indicator for transport block 2
	RV2	2 bits	Redundancy version for transport block 2
	PrecodingInfo	0 bits for two antennas 2 bits for four antennas	Precoding information
	HARQACKResOffset	2 bits	HARQ-ACK resource offset. Present when this format is carried by EPDCCH. Not present when this format is carried by PDCCH
'Format2B'	DCIFormat	-	'Format2B'
	CIF	0 or 3 bits	Carrier indicator field
	AllocationType	1 bit	Resource allocation header: type 0, type 1. If downlink bandwidth is ≤10 PRBs there is no resource allocation header and resource allocation type 0 is assumed.
	Allocation	Varies	Resource block assignment/allocation
	TPCPUCCH	2 bits	PUCCH TPC command
	TDDIndex	2 bits	For TDD config 0, this field is not used. For TDD config 1–6, this field is the Downlink Assignment Index. Not present for FDD.
	HARQNo	3 bits (FDD) 4 bits (TDD)	HARQ process number
	ScramblingId	1 bit	Scrambling identity
	ModCoding1	5 bits	Modulation and coding scheme for transport block 1
	NewData1	1 bit	New data indicator for transport block 1
	RV1	2 bits	Redundancy version for transport block 1
	ModCoding2	5 bits	Modulation and coding scheme for transport block 2
	NewData2	1 bit	New data indicator for transport block 2
	RV2	2 bits	Redundancy version for transport block 2
	HARQACKResOffset	2 bits	HARQ-ACK resource offset. Present when this format is carried by EPDCCH. Not present when this format is carried by PDCCH
'Format2C'	DCIFormat	-	'Format2C'
	CIF	0 or 3 bits	Carrier indicator field
	AllocationType	1 bit	Resource allocation header: type 0, type 1. If downlink bandwidth is ≤10 PRBs there is no resource allocation header and resource allocation type 0 is assumed.
	Allocation	Varies	Resource block assignment/allocation
	TPCPUCCH	2 bits	PUCCH TPC command
	TDDIndex	2 bits	For TDD config 0, this field is not used. For TDD config 1–6, this field is the Downlink Assignment Index. Not present for FDD.
	HARQNo	3 bits (FDD) 4 bits (TDD)	HARQ process number
	TxIndication	3 bits	Antenna ports, scrambling identity, and number of layers indicator
	SRSRequest	Varies	SRS request. Only present for TDD.
	ModCoding1	5 bits	Modulation and coding scheme for transport block 1
	NewData1	1 bit	New data indicator for transport block 1
	RV1	2 bits	Redundancy version for transport block 1
	ModCoding2	5 bits	Modulation and coding scheme for transport block 2
	NewData2	1 bit	New data indicator for transport block 2
	RV2	2 bits	Redundancy version for transport block 2
	HARQACKResOffset	2 bits	HARQ-ACK resource offset. Present when this format is carried by EPDCCH. Not present when this format is carried by PDCCH
'Format2D'	DCIFormat	-	'Format2D'
	CIF	0 or 3 bits	Carrier indicator field
	AllocationType	1 bit	Resource allocation header: type 0, type 1. If downlink bandwidth is ≤10 PRBs there is no resource allocation header and resource allocation type 0 is assumed.
	Allocation	Varies	Resource block assignment/allocation
	TPCPUCCH	2 bits	PUCCH TPC command
	TDDIndex	2 bits	For TDD config 0, this field is not used. For TDD config 1–6, this field is the Downlink Assignment Index. Not present for FDD.
	HARQNo	3 bits (FDD) 4 bits (TDD)	HARQ process number
	TxIndication	3 bits	Antenna ports, scrambling identity, and number of layers indicator
	SRSRequest	Varies	SRS request. Only present for TDD.
	ModCoding1	5 bits	Modulation and coding scheme for transport block 1
	NewData1	1 bit	New data indicator for transport block 1
	RV1	2 bits	Redundancy version for transport block 1
	ModCoding2	5 bits	Modulation and coding scheme for transport block 2
	NewData2	1 bit	New data indicator for transport block 2
	RV2	2 bits	Redundancy version for transport block 2
	REMappingAndQCL	2 bits	PDSCH RE Mapping and Quasi-Co-Location Indicator
	HARQACKResOffset	2 bits	HARQ-ACK resource offset. Present when this format is carried by EPDCCH. Not present when this format is carried by PDCCH
'Format3'	DCIFormat	-	'Format3'
	TPCCommands	Varies	TPC commands for PUCCH and PUSCH
'Format3A'	DCIFormat	-	'Format3A'
	TPCCommands	Varies	TPC commands for PUCCH and PUSCH
'Format4'	DCIFormat	-	'Format4'
	CIF	0 or 3 bits	Carrier indicator field
	Allocation	Varies	Resource block assignment/allocation
	TPC	2 bits	PUSCH TPC command
	CShiftDMRS	3 bits	Cyclic shift for DM-RS
	TDDIndex	2 bits	For TDD config 0, this field is Uplink Index. For TDD config 1–6, this field is the Downlink Assignment Index. Not present for FDD.
	CSIReq	Varies	CSI request
	SRSRequest	2 bits	SRS request
	AllocationType	1 bit	Resource allocation header type 0 or type 1.
	ModCoding	5 bits	Modulation, coding scheme, and redundancy version
	NewData	1 bit	New data indicator
	ModCoding1	5 bits	Modulation and coding scheme for transport block 1
	NewData1	1 bit	New data indicator for transport block 1
	ModCoding2	5 bits	Modulation and coding scheme for transport block 2
	NewData2	1 bit	New data indicator for transport block 2
	PrecodingInfo	3 bits for two antennas 6 bits for four antennas	Precoding information
'Format5'	DCIFormat	-	'Format5'
	PSCCHResource	6 bits	Resource for PSCCH
	TPC	1 bit	TPC command for PSCCH and PSSCH
	FreqHopping	1 bit	Frequency hopping flag
	Allocation	Varies	Resource block assignment and hopping resource allocation
	TimeResourcePattern	7 bits	Time resource pattern
'Format5A'	DCIFormat	-	'Format5A'
	CIF	3 bits	Carrier indicator
	FirstSubchannelIdx	$$\lceil {\log }_2\left(N_{\text{subchannel}}^{\text{SL}}\right)\rceil$$	Lowest index of the subchannel allocation to the initial transmission
	RIV	from 0 to 13 bits, $$\lceil {\log }_2\left(\frac{N_{\text{subchannel}}^{\text{SL}}\times \left(N_{\text{subchannel}}^{\text{SL}}+1\right)}{2}\right)\rceil$$	Resource indication value
	TimeGap	4 bits	Time gap between initial transmission and retransmission
	SLIndex	2 bits	SL SPS configuration index

Data Types: struct

Output Arguments

prbset — Physical resource block indices

nonnegative integer column-vector | nonnegative integer column-matrix

Physical resource block indices, returned as a nonnegative integer column-vector or N-by-2 matrix of zero-based indices. The returned prbset will be a single column vector or a two-column matrix depending on whether the allocation type defines a different set of PRB indices in the first and second slots of the subframe.

Data Types: uint64

nrbg — Number of resource block groups in the allocation

integer

Number of resource block groups in the allocation, returned as an integer.

Data Types: int32

rbgsize — Resource block group size

integer

Number of resource blocks in a group, returned as an integer.

Data Types: int32

More About

Resource Allocation Types

The LTE standard specifies resource allocation types used for downlink, uplink and sidelink. For a detailed description of the resource allocation types, see lteDCI.

• For downlink, the LTE standard specifies three resource allocation types: type 0, 1, and 2. In terms of the DCI formats, formats 1, 2, 2A, 2B, 2C , and 2D can use either resource allocation type 0 or type 1, with the choice signalled by dcistr.AllocationType=0 and dcistr.AllocationType=1 respectively. DCI formats 1A, 1B, 1C, and 1D use resource allocation type 2, which can be configured to be localized or distributed across resource blocks, signalled by dcistr.AllocationType=0 and dcistr.AllocationType=1 respectively.

• For uplink allocations (signaled in DCI format 0 messages), the allocation type is either hopping or non-hopping, signalled by dcistr.FreqHopping=1 and dcistr.FreqHopping=0, respectively.

  • For hopping allocations, there are two types of hopping: type 1 PUSCH hopping and type 2 PUSCH hopping (frequency hopping with a predefined pattern). The hopping type is signalled by dcistr.Allocation.HoppingBits as described in TS 36.213 [1], Table 8.4-2.

  • For non-hopping uplink allocations, there are two types of resource allocation: type 0 and type 1. These are signalled by dcistr.AllocationType=0 and dcistr.AllocationType=1 respectively. In case of DCI format 0 and uplink resource allocation type 1, the concatenation of the frequency hopping flag field (dcistr.FreqHopping) and the resource block assignment and hopping resource allocation field provides the resource allocation field (dcistr.Allocation). Type 0 allocations create a single contiguous set of PRB, whereas type 1 can create two contiguous PRB sets. The DCI format 4 messages can only signal non-hopping resource allocations type 0 and type 1.

• For D2D sidelink PSSCH (signaled by DCI format 5 messages), allocations are the same as uplink PUSCH allocation type 0, both non-hopping and hopping, but with a different set of additional parameters required in the hopping case. Details for sidelink transmission mode 1 and mode 2 are specified in TS 36.213 [1], Sections 14.1.1.2 and 14.1.1.4 respectively.

• Sidelink V2X PSSCH allocations (signalled by DCI format 5A messages when in sidelink transmission mode 3) create a single contiguous set of PRB using one or more sub-channels. See TS 36.213 [1], sections 14.1.1.4A and 14.1.1.4B for sidelink transmission mode 3 and mode 4 respectively. TM2 and TM4 use autonomous scheduling and therefore do not employ DCI messages from the eNodeB to deliver the transmission grants.

All allocations define a single set of PRB for both slots in a subframe (prbset is a column vector) except for the distributed resource allocation type 2 and uplink hopping allocations, where different PRB sets are used across the slot pair.

The allocation type may also define a minimum unit of resource block allocation, which is defined by the resource block group size, rbgsize. This specifies the number of resource blocks in a group. There are nrbg resource block groups in the allocation.

Specifying Number of Resource Blocks

The number of resource blocks specifies the uplink and downlink bandwidth. The LTE Toolbox™ implementation assumes symmetric link bandwidth unless you specifically assign different values to NULRB and NDLRB. If the number of resource blocks is initialized in only one link direction, then the initialized number of resource blocks (NULRB or NDLRB) is used for both uplink and downlink. When this mapping is used, no warning is displayed. An error occurs if NULRB and NDLRB are both undefined.

References

[1] 3GPP TS 36.213. “Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures.” 3rd Generation Partnership Project; Technical Specification Group Radio Access Network. URL: https://www.3gpp.org.

Version History

Introduced in R2014a