B.6 Interference models for enhanced performance requirements Type-B
36.521-13GPPEvolved Universal Terrestrial Radio Access (E-UTRA)Part 1: Conformance testingRadio transmission and receptionRelease 17TSUser Equipment (UE) conformance specification
This clause provides a description for the modelling of interfering cell transmissions for enhanced performance requirements Type-B including: transmission mode 2, 3, 4 and 9 type of interference modelling and a definition of the random interference model.
B.6.1 Transmission mode 2 interference model
This subclause provides transmission mode 2 interference modelling for each explicitly modelled interfering cell in the requirement scenario. In each subframe, each interfering cell shall transmit randomly modulated data over the PDSCH region as specified in subclause B.6.6. Transmitted physical channels shall include PSS, SSS and PBCH.
The MCS shall be randomly determined with probabilities of occurrence of each possible MCS as specified in subclause B.6.6.
Precoding for transmit diversity for the number of antenna ports in the requirement scenario shall be applied to the randomly modulated layer symbols, as specified in subclause 6.3.4.3 of [8].
For unallocated REs in the control region, precoding for transmit diversity for the number of antenna ports in the requirement scenario shall be applied to QPSK randomly modulated layer symbols, as specified in subclause 6.3.4.3 of [8]. The EPRE ratio for these REs shall be as defined for PDCCH in Annex C.3.2.
B.6.2 Transmission mode 3 interference model
This subclause provides transmission mode 3 interference modelling for each explicitly modelled interfering cell in the requirement scenario. In each subframe, each interfering cell shall transmit randomly modulated data over the PDSCH region as specified in subclause B.6.6. Transmitted physical channels shall include PSS, SSS and PBCH.
The transmission rank shall be randomly determined for each user defined in section B.6.6 with probabilities of occurrence of each possible transmission rank as specified in subclause B.6.6.
The MCS shall be randomly determined with probabilities of occurrence of each possible MCS as specified in subclause B.6.6.
For rank-1 transmission, precoding for transmit diversity for the number of antenna ports in the requirement scenario shall be applied to the randomly modulated layer symbols, as specified in subclause 6.3.4.3 of [8].
For rank-2 transmission, precoding for spatial multiplexing with large delay CDD over two layers for the number of antenna ports in the requirement scenario shall be applied to the randomly modulated layer symbols, as specified in subclause 6.3.4.2.2 of [8].
For unallocated REs in the control region, precoding for transmit diversity for the number of antenna ports in the requirement scenario shall be applied to QPSK randomly modulated layer symbols, as specified in subclause 6.3.4.3 of [8]. The EPRE ratio for these REs shall be as defined for PDCCH in Annex C.3.2.
B.6.3 Transmission mode 4 interference model
This subclause provides transmission mode 4 interference modelling for each explicitly modelled interfering cell in the requirement scenario. In each subframe, each interfering cell shall transmit randomly modulated data over the PDSCH region as specified in subclause B.6.6. Transmitted physical channels shall include PSS, SSS and PBCH.
The transmission rank shall be randomly determined with probabilities of occurrence of each possible transmission rank as specified in subclause B.6.6.
The MCS shall be randomly determined with probabilities of occurrence of each possible MCS as specified in subclause B.6.6.
For each TTI, for each user defined in B.6.6, a single precoding matrix for the number of layers 
associated to the selected rank shall be selected randomly from Table 6.3.4.2.3-1 of [8]. Note that codebook index 0 shall be excluded from random precoder selection when the number of layers is 
.
Precoding for spatial multiplexing with cell-specific reference signals for the number of antenna ports in the requirement scenario shall be applied to randomly modulated layer symbols, as specified in subclause 6.3.4.2.1 of [8] with the selected precoding matrices as specified in subclause B.6.6.
For unallocated REs in the control region, precoding for transmit diversity for the number of antenna ports in the requirement scenario shall be applied to QPSK randomly modulated layer symbols, as specified in subclause 6.3.4.3 of [8]. The EPRE ratio for these REs shall be as defined for PDCCH in Annex C.3.2.
B.6.4 Transmission mode 9 interference model
This subclause provides transmission mode 9 interference modelling for each explicitly modelled interfering cell in the requirement scenario. In each subframe, each interfering cell shall transmit randomly modulated data over the PDSCH region as specified in subclause B.6.6. Transmitted physical channels shall include PSS, SSS and PBCH.
The transmission rank shall be randomly determined with probabilities of occurrence of each possible transmission rank as specified in subclause B.6.6.
The MCS shall be randomly determined with probabilities of occurrence of each possible MCS as specified in subclause B.6.6.
For each TTI, for each user defined in B.6.6, a single precoding matrix for the number of layers 
associated to the selected rank shall be selected randomly from Table 6.3.4.2.3-1 of [8]. Note that codebook index 0 shall be excluded from random precoder selection when the number of layers is 
.
The generic beamforming model in subclause B.4.3 shall be applied assuming cell-specific reference signals and CSI reference signals as specified in the requirement scenario. Random precoding with selected rank and precoding matrices for each subframe shall be applied to randomly modulated layer symbols including the user-specific reference symbols over antenna port 7 when the rank is one and antenna ports 7, 8 when the rank is two.
For each TTI, for each user defined in B.6.6, the scrambling ID value nSCID is randomly assigned from the set of {0,1}.
For unallocated REs in the control region, precoding for transmit diversity for the number of antenna ports in the requirement scenario shall be applied to QPSK randomly modulated layer symbols, as specified in subclause 6.3.4.3 of [8]. The EPRE ratio for these REs shall be as defined for PDCCH in Annex C.3.2.
B.6.5 CRS interference model
This subclause provides for the CRS interference modelling for each explicitly modelled interfering cell in the requirement scenario. In each subframe there is no PDSCH transmitted. Transmitted physical channels shall include PSS, SSS and PBCH.
For unallocated REs in the control region, precoding for transmit diversity for the number of antenna ports in the requirement scenario shall be applied to QPSK randomly modulated layer symbols, as specified in subclause 6.3.4.3 of [8]. The EPRE ratio for these REs shall be as defined for PDCCH in Annex C.3.2.
B.6.6 Random interference model
This subclause presents the interference model which defines the resource allocation, MCS and rank for the two interference cells. The model includes approximately 10% DTX on these interference cells. Table B.6.6-1 shows the resource allocation for four users in two different configurations for each of the two interferers. Table B.6.6-2 shows the resource allocation to be used for special subframes with TM9 interference. Table B.6.6-3 shows the probabilities for the MSC and rank for these users.
Table B.6.6-1: Resource allocation for the random interference model
|
Resource allocation configurations Indexes |
User Index |
Resource allocation for random interference model |
Probability |
|||
|
Resource allocation type |
Bitmap for resource allocation (Note 1) |
|||||
|
1st field bitmap |
2nd field bitmap |
3rd field bitmap |
||||
|
Configuration 1 |
User 0 |
1 |
00 |
0 |
10101000101010 |
50% |
|
User 1 |
1 |
00 |
0 |
01010101010101 |
||
|
User 2 |
0 |
01001001001001001 |
||||
|
User 3 |
0 |
00100100100100100 |
||||
|
Configuration 2 |
User 0 |
1 |
00 |
0 |
10101010101010 |
50% |
|
User 1 |
1 |
00 |
1 |
01010100010101 |
||
|
User 2 |
0 |
01001001001001001 |
||||
|
User 3 |
0 |
00100100100100100 |
||||
|
NOTE 1: The 1st, 2nd, and 3rd field bitmaps are only valid for resource allocation type 1 which was defined in [10]. NOTE 2: The resource allocation model is used for both 1st and 2nd interfering cells and the resource allocation is independent for each interfering cell. |
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Table B.6.6-2: Resource allocation for the random interference model for TM9 special subframes
|
Resource allocation configurations Indexes |
User Index |
Resource allocation for random interference model |
Probability |
|||
|
Resource allocation type |
Bitmap for resource allocation (Note 1) |
|||||
|
1st field bitmap |
2nd field bitmap |
3rd field bitmap |
||||
|
Configuration 1 |
User 0 |
1 |
00 |
0 |
10101000101010 |
50% |
|
User 1 |
1 |
00 |
0 |
01010101000001 |
||
|
User 2 |
0 |
01001000001001001 |
||||
|
User 3 |
0 |
00100100000100100 |
||||
|
Configuration 2 |
User 0 |
1 |
00 |
0 |
10101000101010 |
50% |
|
User 1 |
1 |
00 |
1 |
01010000010101 |
||
|
User 2 |
0 |
01001000001001001 |
||||
|
User 3 |
0 |
00100100000100100 |
||||
|
NOTE 1: The 1st, 2nd, and 3rd field bitmaps are only valid for resource allocation type 1 which was defined in [10]. NOTE 2: The resource allocation model is used for both 1st and 2nd interfering cells and the resource allocation is independent for each interfering cell. |
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Table B.6.6-3: MCS and rank configuration for the random interference model
|
MCS probability |
Rank probability |
|||
|
MCS5 |
MCS14 |
MCS25 |
Rank 1 |
Rank 2 |
|
50% |
25% |
25% |
80% |
20% |
|
NOTE 1: The MCS and rank should follow the probability indicated in the table randomly per UE per TTI. NOTE 2: The probabilities for MCS and rank configuration are used for both 1st and 2nd interfering cells. The MCS and rank configurations are independent for each interfering cell. |
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