9.1.5 MPDCCH assignment procedure

36.2133GPPEvolved Universal Terrestrial Radio Access (E-UTRA)Physical layer proceduresRelease 17TS

A BL/CE UE shall monitor a set of MPDCCH candidates on one or more Narrowbands (described in Clause 6.2.7 of [3]) as configured by higher layer signalling for control information, where monitoring implies attempting to decode each of the MPDCCHs in the set according to all the monitored DCI formats. The Narrowband in a subframe used for MPDCCH monitoring is determined as described in [3].

A UE that is not a BL/CE UE is not required to monitor MPDCCH.

A BL/CE UE can derive the configuration of one or two MPDCCH-PRB-sets for MPDCCH monitoring from higher layer signalling. The PRB-pairs corresponding to MPDCCH-PRB-set are indicated by higher layers. Each MPDCCH-PRB-set consists of set of ECCEs numbered from 0 to where is the number of ECCEs in MPDCCH-PRB-set of subframe .

The MPDCCH-PRB-set(s) can be configured by higher layers for either localized MPDCCH transmission or distributed MPDCCH transmission.

The set of MPDCCH candidates to monitor are defined in terms of MPDCCH search spaces.

The BL/CE UE shall monitor one or more of the following search spaces

– a Type0-MPDCCH common search space if configured with CEmodeA, or if configured with CEmodeB and higher layer parameter ce-ETWS-CMAS-RxInConn,

– a Type1-MPDCCH common search space,

– a Type1A-MPDCCH common search space,

– a Type2-MPDCCH common search space,

– a Type2A-MPDCCH common search space, and

– a MPDCCH UE-specific search space.

A BL/CE UE configured with CEModeB is not required to monitor Type0-MPDCCH common search space unless the UE is configured with higher layer parameter ce-ETWS-CMAS-RxInConn.

The BL/CE UE is not required to simultaneously monitor MPDCCH UE-specific search space and Type1-MPDCCH common search space.

The BL/CE UE is not required to simultaneously monitor MPDCCH UE-specific search space and Type2-MPDCCH common search space.

The BL/CE UE is not required to monitor Type1A-MPDCCH common search space or Type2A-MPDCCH common search space if the set of subframes comprising the search space include any subframes in which it monitors Type1-MPDCCH common search space or any subframes in which the UE receives PDSCH assigned by PDCCH with DCI CRC scrambled by P-RNTI.

The BL/CE UE is not required to monitor Type2A-MPDCCH common search space if the set of subframes comprising the search space include any subframes in which it monitors Type1A-MPDCCH common search space or any subframes in which the UE receives PDSCH assigned by MPDCCH with DCI CRC scrambled by SC-RNTI.

A BL/CE UE is not required to monitor Type1-MPDCCH common search space or in case of half-duplex FDD operation MWUS if the set of subframes comprising the search space or the set of subframes where MWUS may be received include any subframes in which the UE has initiated a PUSCH transmission using preconfigured uplink resource on a given serving cell.

A BL/CE UE is not required to monitor Type1-MPDCCH common search space or MWUS in subframes in which the UE monitors a UE-specific MPDCCH search space given by PUR-RNTI.

A BL/CE UE is not expected to monitor an MPDCCH candidate, if an ECCE corresponding to that MPDCCH candidate is mapped to a PRB pair that overlaps with a transmission of PDSCH scheduled previously in the same subframe.

For aggregation level or ECCEs, the number of ECCEs refers to the MPDCCH mapping to the REs of the 2+4 PRB set as defined in [3]. An MPDCCH search space at aggregation level and repetition level is defined by a set of MPDCCH candidates where each candidate is repeated in a set of consecutive BL/CE downlink subframes starting with subframe . For an MPDCCH-PRB-set , the ECCEs corresponding to MPDCCH candidate m of the search space are given by

where

,

is the number of MPDCCH candidates to monitor at aggregation level in MPDCCH-PRB-set in each subframe in the set of consecutive subframes.

for MPDCCH UE-specific search space is determined as described in Clause 9.1.4, and for Type0-MPDCCH common search space, Type1-MPDCCH common search space, Type1A-MPDCCH common search space, Type2-MPDCCH common search space and Type2A-MPDCCH common search space.

For , if subframe is a special subframe that does not support MPDCCH according to table 6.8B.1-1 in [3], the UE shall calculate by assuming for normal cyclic prefix and for extended cyclic prefix.

A BL/CE UE is not expected to monitor MPDCCH in subframes that are not BL/CE DL subframes as defined in clause 7.1.

Until BL/CE UE receives higher layer configuration of MPDCCH UE-specific search space, the BL/CE UE monitors MPDCCH according to the same configuration of MPDCCH search space and Narrowband as that for MPDCCH scheduling Msg4.

The aggregation and repetition levels defining the MPDCCH search spaces and the number of monitored MPDCCH candidates are given as follows:

For MPDCCH UE-specific search space

– if the BL/CE UE is configured with =2 or =4 PRB-pairs, and mPDCCH-NumRepetition=1, and

– if the MPDCCH-PRB-set is configured for distributed transmission, the aggregation levels defining the search spaces and the number of monitored MPDCCH candidates are listed in Table 9.1.4-1a and Table 9.1.4-1b, where is substituted with for ≤24, and is substituted with .

– if the MPDCCH-PRB-set is configured for localized transmission, the aggregation levels defining the search spaces and the number of monitored MPDCCH candidates are listed in Table 9.1.4-2a and Table 9.1.4-2b, where is substituted with and is substituted with .

– otherwise

– if the UE is configured with CEModeA, and =2 or =4, the aggregation and repetition levels defining the search spaces and the number of monitored MPDCCH candidates are listed in Table 9.1.5-1a

– if the UE is configured with CEModeA, and =2+4 , the aggregation and repetition levels defining the search spaces and the number of monitored MPDCCH candidates are listed in Table 9.1.5-1b

– if the UE is configured with CEModeB, and =2 or =4, the aggregation and repetition levels defining the search spaces and the number of monitored MPDCCH candidates are listed in Table 9.1.5-2a

– if the UE is configured with CEModeB, and =2+4 , the aggregation and repetition levels defining the search spaces and the number of monitored MPDCCH candidates are listed in Table 9.1.5-2b

is the number of PRB-pairs configured for MPDCCH UE-specific search space. When =2+4, it is given by the higher layer parameter numberPRB-Pairs-r13, and when =2 or =4, it is given by the higher layer parameter numberPRB-Pairs-r11, except for MPDCCH candidates associated with PUR-RNTI in which case it is given by the higher layer parameter mpdcch-PRB-Pairs-r16 in PUR-Config.

, , , are determined from Table 9.1.5-3 by substituting the value of with the value of higher layer parameter mPDCCH-NumRepetition, except for MPDCCH candidates associated with PUR-RNTI in which case it is given by the value of the higher layer parameter mpdcch-NumRepetition-r16 in PUR-Config.

The PRB-pairs within a Narrowband corresponding to an MPDCCH-PRB-set are indicated by higher layers and are determined using the description given in Clause 9.1.4.4.

If higher layer configuration numberPRB-Pairs-r13 or numberPRB-Pairs in PUR-MPDCCH-Config for MPDCCH-PRB-set is 6, =2+4, and the number of PRB-pairs in an MPDCCH-PRB-set = 2+4.

If Type2-MPDCCH common search space or Type2A-MPDCCH common search space,

– PRB-pairs of the 2 PRB set in the 2+4 PRB set correspond to PRB-pairs with the largest two PRB indices in MPDCCH-PRB-set .

– PRB-pairs of the4 PRB set in the 2+4 PRB set correspond to PRB-pairs with the smallest 4 PRB indices in MPDCCH-PRB-set .

– PRB-pairs of the 2+4 PRB set in the 2+4 PRB set correspond to all PRB-pairs in MPDCCH-PRB-set

Table 9.1.5-1a: MPDCCH candidates monitored by a BL/CE UE
(CEModeA, MPDCCH-PRB-set size – 2PRBs or 4PRBs)

R

L’=2

L’=4

L’=8

L’=16

L’=24

2

r1

2

1

1

0

0

4

1

1

1

1

0

2

r2

2

1

1

0

0

4

1

1

1

1

0

2

r3

2

1

1

0

0

4

1

1

1

1

0

2

r4

2

1

1

0

0

4

1

1

1

1

0

Table 9.1.5-1b: MPDCCH candidates monitored by a BL/CE UE
(CEModeA, MPDCCH-PRB-set size – 2+4PRBs)

MPDCCH PRB set

R

L’=2

L’=4

L’=8

L’=16

L’=24

2 PRB set in 2+4 PRB set

r1

1

1

0

0

0

4 PRB set in 2+4 PRB set

0

0

2

1

0

Both PRB sets in 2+4 PRB set

0

0

0

0

1

2 PRB set in 2+4 PRB set

r2

0

1

1

0

0

4 PRB set in 2+4 PRB set

0

0

2

1

0

Both PRB sets in 2+4 PRB set

0

0

0

0

1

2 PRB set in 2+4 PRB set

r3

0

0

0

0

0

4 PRB set in 2+4 PRB set

0

0

1

1

0

Both PRB sets in 2+4 PRB set

0

0

0

0

1

2 PRB set in 2+4 PRB set

r4

0

0

0

0

0

4 PRB set in 2+4 PRB set

0

0

0

0

0

Both PRB sets in 2+4 PRB set

0

0

0

0

1

Table 9.1.5-2a: MPDCCH candidates monitored by a BL/CE UE
(CEModeB, MPDCCH-PRB-set size – 2PRBs or 4PRBs)

R

L’=2

L’=4

L’=8

L’=16

L’=24

2

r1

0

0

1

0

0

4

0

0

1

1

0

2

r2

0

0

1

0

0

4

0

0

1

1

0

2

r3

0

0

1

0

0

4

0

0

1

1

0

2

r4

0

0

1

0

0

4

0

0

1

1

0

Table 9.1.5-2b: MPDCCH candidates monitored by a BL/CE UE
(CEModeB, MPDCCH-PRB-set size – 2+4PRBs)

MPDCCH PRB set

R

L’=2

L’=4

L’=8

L’=16

L’=24

2 PRB set in 2+4 PRB set

r1

0

0

1

0

0

4 PRB set in 2+4 PRB set

0

0

0

1

0

Both PRB sets in 2+4 PRB set

0

0

0

0

1

2 PRB set in 2+4 PRB set

r2

0

0

1

0

0

4 PRB set in 2+4 PRB set

0

0

0

1

0

Both PRB sets in 2+4 PRB set

0

0

0

0

1

2 PRB set in 2+4 PRB set

r3

0

0

1

0

0

4 PRB set in 2+4 PRB set

0

0

0

1

0

Both PRB sets in 2+4 PRB set

0

0

0

0

1

2 PRB set in 2+4 PRB set

r4

0

0

1

0

0

4 PRB set in 2+4 PRB set

0

0

0

1

0

Both PRB sets in 2+4 PRB set

0

0

0

0

1

Table 9.1.5-3: Determination of repetition levels

1

1

2

1

2

4

1

2

4

>=8

Table 9.1.5-4: Repetition levels for Type1/1A-MPDCCH common search space

256

2

16

64

256

128

2

16

64

128

64

2

8

32

64

32

1

4

16

32

16

1

4

8

16

8

1

2

4

8

4

1

2

4

2

1

2

1

1

For Type0-MPDCCH common search space, the narrowband location and the MPDCCH-PRB-set are the same as for MPDCCH UE-specific search space, and

– if =2,

=1 for =8 and repetition levels ,, , given in Table 9.1.5.-3. For all other cases, =0

– if =4,

=1 for =16 and repetition levels ,, , given in Table 9.1.5.-3. For all other cases, =0

– if =2+4,

=1 for =24 and repetition levels ,, , given in Table 9.1.5.-3. For all other cases, =0

where , , , are determined from Table 9.1.5-3 by substituting the value of with the value of higher layer parameter mPDCCH-NumRepetition.

For Type1-MPDCCH common search space and Type1A-MPDCCH common search space, the number of PRB-pairs in MPDCCH-PRB-set is 2+4 PRB-pairs, and

=1 for =24 and repetition levels ,, , where the repetition levels are determined from Table 9.1.5-4 by substituting the value of

– with higher layer parameter mPDCCH-NumRepetition-Paging for Type1-MPDCCH common search space, and

– with higher layer parameter mpdcch-NumRepetitions-SC-MCCH for Type1A-MPDCCH common search space.

– For all other cases, =0

For Type2-MPDCCH common search space, the number of PRB-pairs in MPDCCH-PRB-set is 2+4 PRB-pairs, and

– If the most recent coverage enhancement level used for PRACH is coverage enhancement level 0 and 1, the aggregation and repetition levels defining the search spaces and the number of monitored MPDCCH candidates are determined from Table 9.1.5-1b, by assuming that the number of candidates for <8 as zero.

– If the most recent coverage enhancement level used for PRACH is coverage enhancement level 2 and 3, the aggregation and repetition levels defining the search spaces and the number of monitored MPDCCH candidates are determined from Table 9.1.5-2b.

where , , , are determined from Table 9.1.5-3 by substituting the value of with the value of higher layer parameter mPDCCH-NumRepetition-RA.

For Type2A-MPDCCH common search space, the number of PRB-pairs in MPDCCH-PRB-set is 2+4 PRB-pairs, and

– for CEModeA, the aggregation and repetition levels defining the search spaces and the number of monitored MPDCCH candidates are determined from Table 9.1.5-1b, by assuming that the number of candidates for <8 as zero,

– for CEModeB, the aggregation and repetition levels defining the search spaces and the number of monitored MPDCCH candidates are determined from Table 9.1.5-2b,

where , , , are determined from Table 9.1.5-3 by substituting the value of with the value of higher layer parameter mpdcch-NumRepetitions-SC-MTCH.

In tables 9.1.5-1a, 9.1.5-1b, 9.1.5-2a, 9.1.5-2b, and for MPDCCH UE-specific search space when BL/CE UE is configured with =2+4 or mPDCCH-NumRepetition > 1 or mpdcch-NumRepetition > 1 in PUR-MPDCCH-Config, Type0, Type1, Type1A, Type2, Type2A MPDCCH common search space, is applied for =4, and is applied for =8 wherein substituting the values of .

If a BL/CE UE is configured with higher layer parameter localizedMappingType in CRS-ChEstMPDCCH-ConfigDedicated set to ‘CSI-based’ or ‘Reciprocity-based’, and the MPDCCH-PRB-set is configured for localized transmission, and for MPDCCH UE-specific search space or Type0-MPDCCH common search space, the UE may assume the relation between the DMRS and the CRS ports follows the predefined mapping type (as defined in [3]), for the following MPDCCH candidates

– if , MPDCCH candidates with aggregation level and repetition levels ,, ,

– if , MPDCCH candidates with aggregation level and repetition levels ,, ,

– if , MPDCCH candidates with aggregation level and repetition levels ,, ,

and for other MPDCCH candidates,

– if higher layer parameter localizedMappingType in CRS-ChEstMPDCCH-ConfigDedicated is set to ‘CSI-based’ the UE may assume the relation between DMRS and CRS ports, as defined in [3], is based on a most recent reported PMI ending no later than subframe .

– if higher layer parameter localizedMappingType in CRS-ChEstMPDCCH-ConfigDedicated is set to ‘Reciprocity-based’, the UE shall not assume any relation between the DMRS and CRS ports.

If a BL/CE UE is configured with higher layer parameter localizedMappingType in CRS-ChEstMPDCCH-ConfigDedicated set to ‘CSI-based’ or ‘Reciprocity-based’, and the MPDCCH-PRB-set is configured for localized transmission, and or , and , for MPDCCH UE-specific search space or Type0-MPDCCH common search space, the antenna port for MPDCCH candidates with aggregation level shall be changed as specified in [3].

For Type1-MPDCCH common search space, Type1A-MPDCCH common search space, Type2-MPDCCH common search space and Type2A-MPDCCH common search space, distributed MPDCCH transmission is used.

For MPDCCH UE-specific search space given by PUR-RNTI, distributed MPDCCH transmission is used.

For MPDCCH UE-specific search space, Type0-MPDCCH common search space, Type1A-MPDCCH common search space, Type2-MPDCCH common search space and Type2A-MPDCCH common search space locations of starting subframe are given by where is the th consecutive BL/CE DL subframe from subframe , and , and , and , where

– subframe is a subframe satisfying the condition , where

– For MPDCCH UE-specific search space and Type0-MPDCCH common search space, is given by the higher layer parameter mPDCCH-startSF-UESS, except for MPDCCH candidates associated with PUR-RNTI in which case it is given by the higher layer parameter mpdcch-startSF-UESS-r16 in PUR-Config,

– For Type1A-MPDCCH common search space, is given by the higher layer parameter mpdcch-startSF-SC-MCCH

– For Type2-MPDCCH common search space, is given by the higher layer parameter mPDCCH-startSF-CSS-RA-r13

– For Type2A-MPDCCH common search space, is given by the higher layer parameter mpdcch-startSF-SC-MTCH

is given by the higher layer parameter mpdcch-Offset-SC-MTCH for Type2A-MPDCCH common search space, and by the higher layer parameter mpdcch-Offset-PUR-SS-r16 in PUR-Config for MPDCCH candidates associated with PUR-RNTI, and otherwise; and

is given by the higher layer parameter mPDCCH-NumRepetition for MPDCCH UE-specific search space and Type0-MPDCCH common search space, except for MPDCCH candidates associated with PUR-RNTI in which case it is given by the higher layer parameter mpdcch-NumRepetition-r16 in PUR-Config, and mPDCCH-NumRepetition-RA for Type2-MPDCCH common search space, and mpdcch-NumRepetitions-SC-MCCH for Type1A-MPDCCH common search space, and mpdcch-NumRepetitions-SC-MTCH for Type2A-MPDCCH common search space and

, , , are given in Table 9.1.5-3.

A BL/CE UE is not expected to be configured with values of and that result in non-integer values of .

For Type1-MPDCCH common search space, = and is determined from locations of paging opportunity subframes,

If SystemInformationBlockType1-BR or SI message is transmitted in one narrowband in subframe , a BL/CE UE shall assume MPDCCH in the same narrowband in the subframe is dropped.

The BL/CE UE is not required to monitor an MPDCCH search space if any ECCEs corresponding to any of its MPDCCH candidates occur within a frame before and also occur within frame.

The BL/CE UE is not required to monitor an MPDCCH search space during the PUSCH transmission gap as defined in clause 5.3.4 of [3].

The BL/CE UE is not expected to be configured with overlapping MPDCCH search spaces of the same type.

A BL/CE UE configured to monitor MPDCCH candidates with CRC scrambled by C-RNTI or SPS C-RNTI with the same payload size and with the same aggregation level in the Type0-MPDCCH common search space and the MPDCCH UE-specific search space shall assume that for the MPDCCH candidates with CRC scrambled by C-RNTI or SPS C-RNTI, only the MPDCCH in the UE specific search space is transmitted.

For MPDCCH UE-specific search space or for Type0-MPDCCH common search space if the higher layer parameter mPDCCH-NumRepetition is set to 1 or the higher layer parameter mpdcch-NumRepetition in PUR-MPDCCH-Config is set to 1; or for Type2-MPDCCH common search space if the higher layer parameter mPDCCH-NumRepetition-RA is set to 1; or for Type2A-MPDCCH common search space if the higher layer parameter mpdcch-NumRepetitions-SC-MTCH is set to 1;

– The BL/CE UE is not required to monitor MPDCCH

– For TDD and normal downlink CP, in special subframes for the special subframe configurations 0 and 5 shown in Table 4.2-1 of [3], or for the special subframe configuration 10 configured by the higher layer signalling ssp10-CRS-LessDwPTS

– For TDD and extended downlink CP, in special subframes for the special subframe configurations 0, 4 and 7 shown in Table 4.2-1 of [3];

otherwise

– The BL/CE UE is not required to monitor MPDCCH

– For TDD, in special subframes, if the BL/CE UE is configured with CEModeB

– For TDD and normal downlink CP, in special subframes for the special subframe configurations 0, 1, 2, 5, 6, 7, 9, and 10 shown in Table 4.2-1 of [3], if the BL/CE UE is configured with CEModeA

– For TDD and extended downlink CP, in special subframes for the special subframe configurations 0, 4 and 7 shown in Table 4.2-1 of [3], if the BL/CE UE is configured with CEModeA.

– For TDD, in special subframes, for MPDCCH in Type1/1A-MPDCCH common search space.

If the UE has initiated a PUSCH transmission using preconfigured uplink resource ending in subframe n, the UE shall monitor the MPDCCH UE-specific search space in a search space window starting in subframe n+4+Kmac with duration given by higher layer parameter pur-MPDCCH-SS-window-duration where is provided by higher layer parameter K-mac, otherwise . Upon detection of a MPDCCH with DCI format 6-0A/6-0B with CRC scrambled by PUR-RNTI intended for the UE within the search space window and the corresponding DCI is for PUR ACK/fallback indication (as defined in [4]), the UE is not required to monitor the MPDCCH UE-specific search space for the remaining search space window duration.

The number of MPDCCH repetitions is indicated in the ‘DCI subframe repetition number’ field in the DCI according to the mapping in Table 9.1.5-5. For a BL/CE UE in half-duplex FDD operation, if the UE is configured with CEModeA, and configured with higher layer parameter ce-HARQ-AckBundling, and ‘HARQ-ACK bundling flag’ in the corresponding DCI is set to 1, the UE shall assume the number of MPDCCH repetitions as 1.

Table 9.1.5-5: Mapping for DCI subframe repetition number

R

DCI subframe repetition number

00

01

10

11

9.1.5.1 MPDCCH starting position

The starting OFDM symbol for MPDCCH given by index in the first slot in a subframe and is determined as follows

is given by the higher layer parameter startSymbolBR

– if subframe is a special subframe or configured as an MBSFN subframe, and if the BL/CE UE is configured in CEModeA

– else

.

9.1.5.2 Antenna ports quasi co-location for MPDCCH

Regardless of transmission modes configuration of PDSCH data transmissions, the BL/CE UE may assume the antenna ports 0 – 3, 107 – 110 of the serving cell are quasi co-located (as defined in [3]) with respect to Doppler shift, Doppler spread, average delay, and delay spread.

9.1.5.3 Preconfigured Uplink Resource ACK/fallback procedure

If a UE has initiated a PUSCH transmission using preconfigured uplink resource on a given serving cell, and upon detection of a MPDCCH with DCI format 6-0A/6-0B with CRC scrambled by PUR-RNTI intended for the UE within the PUR search space window as defined in Clause 9.1.5, and the corresponding DCI is for PUR ACK/fallback indication (as defined in [4]),

– the UE shall deliver the PUR ACK/fallback indication, as signalled on the MPDCCH, to the higher layers, and

– the UE shall deliver to higher layers a 3-bit PUSCH repetition adjustment as signalled on the MPDCCH, where a bit with a value of 0 shall be prepended to the DCI field if the DCI field has a size of 2 bits.