UE Category for PHY layer throughput
UE Category is the set of information (parameters) that defines the maximum throughput for a UE. As LTE evolves, the length of UE category list gets longer and longer, and the interpretation of the category gets more complicated, you will need to go through many tables listed below to figure out the exact throughput capability of a UE. Followings are the list of tables you would need to go through for the detailed understanding.
- RRC Message (UE Capability Information) that defines UE Category
- UE Category Tables
- 36.306 Table 4.1-1: Downlink physical layer parameter values set by the field ue-Category
- 36.306 Table 4.1-2: Uplink physical layer parameter values set by the field ue-Category
- 36.306 Table 4.1A-1: Downlink physical layer parameter values set by the field ue-CategoryDL
- 36.306 Table 4.1A-2: Uplink physical layer parameter values set by the field ue-CategoryUL
- 36.306 Table 4.1A-6: supported DL/UL Categories combinations set by the fields ue-CategoryDL and ue-CategoryUL and UE categories to be indicated
- 36.306 Table 4.1A-6: supported DL/UL Categories combinations set by the fields ue-CategoryDL and ue-CategoryUL and UE categories to be indicated
- 36.306 Table 4.1-3: Total layer 2 buffer sizes set by the field ue-Category
- 36.306 Table 4.1A-3: Total layer 2 buffer sizes set by the fields ue-CategoryDL and ue-CategoryUL
- 36.306 Table 4.1-4: Maximum number of bits of a MCH transport block received within a TTI set by the field ue-Category for an MBMS capable UE
- 36.306 Table 4.1-5: Half-duplex FDD operation type set by the field ue-Category for a half-duplex FDD capable UE
- 36.306 Table A-1: Maximum values for DL PDCP SDUs per TTI
RRC Message (UE Capability Information) that defines UE Category
The category that UE support is indicated in UE Capability Information message as shown below. Notice that ue-Category can specify only up to Cat 4. The category higher than 4 should be assinged to another IE (Information Element) ue-Category-v1020. (Here we are having similar confusing IEs as in WCDMA/HSPA. So many different places to check to figure out exact category)
Example 1 >
ueCapabilityInformation-r8
ue-CapabilityRAT-ContainerList: 1 item
Item 0
UE-CapabilityRAT-Container
rat-Type: eutra (0)
ueCapabilityRAT-Container: ....
UE-EUTRA-Capability
accessStratumRelease: rel11 (3)
ue-Category: 4
...
phyLayerParameters
.... 0... ue-TxAntennaSelectionSupported: False
.... .0.. ue-SpecificRefSigsSupported: False
rf-Parameters
supportedBandListEUTRA: 15 items...
measParameters
bandListEUTRA: 15 items
...
featureGroupIndicators: ...
...
interRAT-Parameters
...
nonCriticalExtension
phyLayerParameters-v920
...
interRAT-ParametersGERAN-v920
...
interRAT-ParametersUTRA-v920
...
csg-ProximityIndicationParameters-r9
neighCellSI-AcquisitionParameters-r9
...
son-Parameters-r9
...
nonCriticalExtension
lateNonCriticalExtension:...
UE-EUTRA-Capability-v9a0-IEs
featureGroupIndRel9Add-r9: ...
...
fdd-Add-UE-EUTRA-Capabilities-r9
phyLayerParameters-r9
...
featureGroupIndicators-r9: ...
...
featureGroupIndRel9Add-r9: ...
...
tdd-Add-UE-EUTRA-Capabilities-r9
phyLayerParameters-r9
...
featureGroupIndicators-r9: ...
...
featureGroupIndRel9Add-r9: ...
...
nonCriticalExtension
ue-Category-v1020: 6
phyLayerParameters-v1020
multiClusterPUSCH-WithinCC-r10: supported (0)
nonContiguousUL-RA-WithinCC-List-r10: ...
...
rf-Parameters-v1020
supportedBandCombination-r10: ...
...
measParameters-v1020
bandCombinationListEUTRA-r10: ...
...
featureGroupIndRel10-r10: ...
...
ue-BasedNetwPerfMeasParameters-r10
...
nonCriticalExtension
fdd-Add-UE-EUTRA-Capabilities-v1060
featureGroupIndRel10-v1060: ...
...
tdd-Add-UE-EUTRA-Capabilities-v1060
featureGroupIndRel10-v1060: ...
...
rf-Parameters-v1060
supportedBandCombinationExt-r10: ...
...
nonCriticalExtension
nonCriticalExtension
pdcp-Parameters-v1130
phyLayerParameters-v1130
crs-InterfHandl-r11: supported (0)
tdd-SpecialSubframe-r11: supported (0)
rf-Parameters-v1130
supportedBandCombination-v1130: ...
...
measParameters-v1130
interRAT-ParametersCDMA2000-v1130
otherParameters-r11
nonCriticalExtension
ue-Category-v1170: 9
nonCriticalExtension
Example 2 >
UE-EUTRA-Capability ::= SEQUENCE [11]
+-accessStratumRelease ::= ENUMERATED [rel11]
+-ue-Category ::= INTEGER (1..5) [4]
+-pdcp-Parameters ::= SEQUENCE [0]
+-phyLayerParameters ::= SEQUENCE
+-rf-Parameters ::= SEQUENCE
+-measParameters ::= SEQUENCE
+-featureGroupIndicators ::= BIT STRING SIZE(32) OPTIONAL:Exist
+-interRAT-Parameters ::= SEQUENCE [0000000]
+-nonCriticalExtension ::= SEQUENCE [0001] OPTIONAL:Exist
+-nonCriticalExtension ::= SEQUENCE [11] OPTIONAL:Exist
+-lateNonCriticalExtension ::= OCTET STRING CONSTRAINTED
+-nonCriticalExtension ::= SEQUENCE [111110101] OPTIONAL:Exist
+-ue-Category-v1020 ::= INTEGER (6..8) [7] OPTIONAL:Exist
+-phyLayerParameters-v1020 ::= SEQUENCE [0000011] OPTIONAL:Exist
+-rf-Parameters-v1020 ::= SEQUENCE OPTIONAL:Exist
+-measParameters-v1020 ::= SEQUENCE OPTIONAL:Exist
+-featureGroupIndRel10-r10 ::= BIT STRING SIZE(32)
+-interRAT-ParametersCDMA2000-v1020 ::= SEQUENCE OPTIONAL:Omit
+-ue-BasedNetwPerfMeasParameters-r10 ::= SEQUENCE [11] OPTIONAL:Exist
+-interRAT-ParametersUTRA-TDD-v1020 ::= SEQUENCE OPTIONAL:Omit
+-nonCriticalExtension ::= SEQUENCE [0011] OPTIONAL:Exist
+-fdd-Add-UE-EUTRA-Capabilities-v1060 ::= SEQUENCE OPTIONAL:Omit
+-tdd-Add-UE-EUTRA-Capabilities-v1060 ::= SEQUENCE OPTIONAL:Omit
+-rf-Parameters-v1060 ::= SEQUENCE OPTIONAL:Exist
+-nonCriticalExtension ::= SEQUENCE [01] OPTIONAL:Exist
+-rf-Parameters-v1090 ::= SEQUENCE OPTIONAL:Omit
+-nonCriticalExtension ::= SEQUENCE [1001] OPTIONAL:Exist
+-nonCriticalExtension ::= SEQUENCE [011] OPTIONAL:Exist
+-phyLayerParameters-v1170 ::= SEQUENCE OPTIONAL:Omit
+-ue-Category-v1170 ::= INTEGER (9..10) [10] OPTIONAL:Exist
+-nonCriticalExtension ::= SEQUENCE [10001] OPTIONAL:Exist
+-rf-Parameters-v1180 ::= SEQUENCE [100] OPTIONAL:Exist
+-mbms-Parameters-r11 ::= SEQUENCE OPTIONAL:Omit
+-fdd-Add-UE-EUTRA-Capabilities-v1180 ::= SEQUENCE OPTIONAL:Omit
+-tdd-Add-UE-EUTRA-Capabilities-v1180 ::= SEQUENCE OPTIONAL:Omit
+-nonCriticalExtension ::= SEQUENCE [101] OPTIONAL:Exist
+-ue-Category-v11a0 ::= INTEGER (11..12) [12] OPTIONAL:Exist
+-measParameters-v11a0 ::= SEQUENCE OPTIONAL:Omit
+-nonCriticalExtension ::= SEQUENCE [010011000000001] OPTIONAL:Exist
+-phyLayerParameters-v1250 ::= SEQUENCE OPTIONAL:Omit
+-rf-Parameters-v1250 ::= SEQUENCE [1000] OPTIONAL:Exist
+-rlc-Parameters-r12 ::= SEQUENCE OPTIONAL:Omit
+-ue-BasedNetwPerfMeasParameters-v1250 ::= SEQUENCE OPTIONAL:Omit
+-ue-CategoryDL-r12 ::= INTEGER (0..14) [12] OPTIONAL:Exist
+-ue-CategoryUL-r12 ::= INTEGER (0..13) [13] OPTIONAL:Exist
+-wlan-IW-Parameters-r12 ::= SEQUENCE OPTIONAL:Omit
+-measParameters-v1250 ::= SEQUENCE OPTIONAL:Omit
+-dc-Parameters-r12 ::= SEQUENCE OPTIONAL:Omit
+-mbms-Parameters-v1250 ::= SEQUENCE OPTIONAL:Omit
+-mac-Parameters-r12 ::= SEQUENCE OPTIONAL:Omit
+-fdd-Add-UE-EUTRA-Capabilities-v1250 ::= SEQUENCE OPTIONAL:Omit
+-tdd-Add-UE-EUTRA-Capabilities-v1250 ::= SEQUENCE OPTIONAL:Omit
+-sl-Parameters-r12 ::= SEQUENCE OPTIONAL:Omit
+-nonCriticalExtension ::= SEQUENCE [11] OPTIONAL:Exist
+-ue-CategoryDL-v1260 ::= INTEGER (15..16) [16] OPTIONAL:Exist
+-nonCriticalExtension ::= SEQUENCE [10] OPTIONAL:Exist
+-rf-Parameters-v1270 ::= SEQUENCE [10] OPTIONAL:Exist
+-nonCriticalExtension ::= SEQUENCE OPTIONAL:Omit
36.306 defines the maximum throughput for each category as follows :
Note : Following throughput does not make difference about the number of Carriers. When you are talking about Categories about Carrier Aggregation throughput, you would be clear on whether you are talking about the category for each component carrier or categories of aggregated carriers.
This tables tells you only about the maximum throughput, it doesn't tell in detail about how you achieve it. Many people tries to associate this table to a specific MIMO configuration or Carrier Aggregation(CA) configuration. But there is no direction connection between this table and MIMO/CA condition.
< 36.306 v12.6 Table 4.1-1: Downlink physical layer parameter values set by the field ue-Category >
< 36.306 v12.6 Table 4.1-2: Uplink physical layer parameter values set by the field ue-Category >
Note 1 : The number shown in this table is the number of bits that can be transmitted in 1 TTI (1 ms). So you have to multiply this number by 1000 to get the rate in 'bps'. For example, Table 4.1-1 Category 3 says 102048. If you convert this number into bps, it is 102048 x 1000 = 102,048,000 bps.
Note 2 : You should be very careful when you talk about the throughput in Kbps, Mbps unit. A lot of people do the conversion by dividing the number by 1000, 1000000. But in digital theory (especially in computer world) 1 Kbps is 2^10 bits and 1 Mbps is 2^20 bits. When the number is small, you don't see much difference, however when the number is very big, the difference between the two different conversion would give you huge difference.
Note 3 : The number shows in this table is based on the assumption that all the DL/UL TTI carries only user data (U-Plane Data), but in really you cannot allocate 100% of resources for user data only. There should be a certain portion of overhead (like SIBs, MAC CE, Signaling etc). So real throughput you get will be less than the one listed in this table.
In Release 12, there are other categories in which we can specify DL category and UL category separately as shown below.
ueCapabilityInformation-r8
ue-CapabilityRAT-ContainerList: 1 item
Item 0
UE-CapabilityRAT-Container
rat-Type: eutra (0)
ueCapabilityRAT-Container: ....
UE-EUTRA-Capability
accessStratumRelease: ...
ue-Category: 4
...
nonCriticalExtension
...
nonCriticalExtension
lateNonCriticalExtension:...
....
nonCriticalExtension
ue-Category-v1020: 6
...
nonCriticalExtension
...
nonCriticalExtension
nonCriticalExtension
....
nonCriticalExtension
ue-Category-v1170: 9
nonCriticalExtension
phyLayerParameters-v1250
rf-Parameters-v1250
rlc-Parameters-r12
ue-BasedNetwPerMeasParameters-v1250
ue-CategoryDL-r12 : 14
ue-CategoryUL-r12 : 13
wlan-IW-Parameters-r12
measParameters-r1250
dc-Parameters-r12
mbms-Parameters-r12
mac-Parameters-r12
fdd-Add-UE-EUTRA-Capabilities-v1250
fdd-Add-UE-EUTRA-Capabilities-v1250
sl-Parameters-r12
nonCriticalExtension
< 36.306 v14.5 - Table 4.1A-1: Downlink physical layer parameter values set by the field ue-CategoryDL >
|
UE DL Category |
Maximum number of DL-SCH transport block bits received within a TTI |
Maximum number of bits of a DL-SCH transport block received within a TTI |
Total number of soft channel bits |
Maximum number of supported layers for spatial multiplexing in DL |
| DL Category M1 |
1,000 |
1,000 |
25,344 |
1 |
| DL Category M2 |
4,008 |
4,008 |
73,152 |
1 |
| DL Category 0 |
1,000 |
1,000 |
25,344 |
1 |
| DL Category 1bis |
10,296 |
10,296 |
250,368 |
1 |
| DL Category 4 |
150,752 |
75,376 |
1,827,072 |
2 |
| DL Category 6 |
301,504 |
149,776 (4 layers, 64QAM) |
3,654,144 |
2 or 4 |
| DL Category 7 |
301,504 |
149,776 (4 layers, 64QAM) |
3,654,144 |
2 or 4 |
| DL Category 9 |
452,256 |
149,776 (4 layers, 64QAM) |
5,481,216 |
2 or 4 |
| DL Category 10 |
452,256 |
149,776 (4 layers, 64QAM) |
5,481,216 |
2 or 4 |
| DL Category 11 |
603,008 |
149,776 (4 layers, 64QAM) |
7,308,288 |
2 or 4 |
| DL Category 12 |
603,008 |
149,776 (4 layers, 64QAM) |
7,308,288 |
2 or 4 |
| DL Category 13 |
391,632 |
195,816 (4 layers, 256QAM) |
3,654,144 |
2 or 4 |
| DL Category 14 |
3,916,560 |
391,656 (8 layers, 256QAM) |
47,431,680 |
8 |
| DL Category 15 |
749,856-807,744
|
149,776 (4 layers, 64QAM) 195,816 (4 layers, 256QAM, if alternativeTBS-Index-r14 is not supported) 201,936 (4 layers, 256QAM, if alternativeTBS-Index-r14 is supported) 75,376 (2 layers, 64QAM) 97,896 (2 layers, 256QAM, if alternativeTBS-Index-r14 is not supported) 100,752 (2 layers, 256QAM, if alternativeTBS-Index-r14 is supported) |
9,744,384 |
2 or 4 |
| DL Category 16 |
978,960 -1,051,360 |
149,776 (4 layers, 64QAM) 195,816 (4 layers, 256QAM, if alternativeTBS-Index-r14 is not supported) 201,936 (4 layers, 256QAM, if alternativeTBS-Index-r14 is supported) 75,376 (2 layers, 64QAM) 97,896 (2 layers, 256QAM, if alternativeTBS-Index-r14 is not supported) 100,752 (2 layers, 256QAM, if alternativeTBS-Index-r14 is supported) |
12,789,504 |
2 or 4 |
| DL Category 17 |
25,065,984 |
391,656 (8 layers, 256QAM) |
303,562,752 |
8 |
| DL Category 18 |
1,174,752-1,211,616 |
299,856 (8 layers, 64QAM) 391,656 (8 layers, 256QAM) 149,776 (4 layers, 64QAM) 195,816 (4 layers, 256QAM, if alternativeTBS-Index-r14 is not supported) 201,936 (4 layers, 256QAM, if alternativeTBS-Index-r14 is supported) 75,376 (2 layers, 64QAM) 97,896 (2 layers, 256QAM, if alternativeTBS-Index-r14 is not supported) 100,752 (2 layers, 256QAM, if alternativeTBS-Index-r14 is supported) |
14,616,576 |
2 or 4 [or 8] |
| DL Category 19 |
1,566,336 -1,658,272 |
299,856 (8 layers, 64QAM) 391,656 (8 layers, 256QAM)] 149,776 (4 layers, 64QAM) 195,816 (4 layers, 256QAM, if alternativeTBS-Index-r14 is not supported) 201,936 (4 layers, 256QAM, if alternativeTBS-Index-r14 is supported) 75,376 (2 layers, 64QAM) 97,896 (2 layers, 256QAM, if alternativeTBS-Index-r14 is not supported) 100,752 (2 layers, 256QAM, if alternativeTBS-Index-r14 is supported) |
19,488,768 |
2 or 4 [or 8] |
| DL Category 20 |
1,948,064 - 2,019,360 |
299,856 (8 layers, 64QAM, 391,656 (8 layers, 256QAM)] 149,776 (4 layers, 64QAM) 195,816 (4 layers, 256QAM, if alternativeTBS-Index-r14 is not supported) 201,936 (4 layers, 256QAM, if alternativeTBS-Index-r14 is supported) 75,376 (2 layers, 64QAM) 97,896 (2 layers, 256QAM, if alternativeTBS-Index-r14 is not supported) 100,752 (2 layers, 256QAM, if alternativeTBS-Index-r14 is supported) |
24,360,960 |
2 or 4 [or 8] |
< 36.306 v13.4 - Table 4.1A-2: Uplink physical layer parameter values set by the field ue-CategoryUL >
< 36.306 v12.6 - Table 4.1A-6: supported DL/UL Categories combinations set by the fields ue-CategoryDL and ue-
CategoryUL and UE categories to be indicated >
To implement the specified UE category, we need to consider various factors along the full stack. Followings are some parameters above Physical layer.
< 36.306 v12.6 Table 4.1-3: Total layer 2 buffer sizes set by the field ue-Category >
< 36.306 v13.4 Table 4.1A-3: Total layer 2 buffer sizes set by the fields ue-CategoryDL and ue-CategoryUL >
< 36.306 v12.6 Table 4.1-4: Maximum number of bits of a MCH transport block received within a TTI set by the field ue-Category for an MBMS capable UE >
< 36.306 v12.6 Table 4.1-5: Half-duplex FDD operation type set by the field ue-Category for a half-duplex FDD capable UE >
Following table represents the max number of PDCP SDUs for each Category. I think this is just enough to achieve the phy/mac max throughput (Table 4.1-1) when the packet size of user data (e.g, IP data) is very large. If the packet size is very small, you would not achieve the maximum throughput at IP level with this number of PDCP SDUs.
< 36.306 v14.5 Table A-1: Maximum values for DL PDCP SDUs per TTI >
|
UE Category / ue-CategoryDL |
Maximum number of PDCP SDUs per TTI |
|
Category 1 |
10 |
|
Category 1bis |
10 |
|
Category 2 |
10 |
|
Category 3 |
20 |
|
Category 4 / DL Category 4 |
30 |
|
Category 5 |
50 |
|
Category 6 / DL Category 6 |
50 |
|
Category 7 / DL Category 7 |
50 |
|
Category 9 / DL Category 9 |
80 |
|
Category 10 / DL Category 10 |
80 |
|
Category 11 / DL Category 11 |
100 |
|
Category 12 / DL Category 12 |
100 |
|
DL Category 13 |
65 |
|
DL Category 15 |
130 |
|
DL Category 16 |
180 |
|
DL Category 18 |
200 |
|
DL Category 19 |
280 |
|
DL Category 20 |
360 |