Instead of 2 antennas on the tower, there are 4.
This leads to a slightly improved experience with phones and modems that have 2 antennas, and a substantially improved experience with phones and modems that have 4.
2021 phones with 4 antennas may cost 3000GHS or more (new condition).
Rank 4, which is depicted by the image above, is when there are 4 antennas in the mobile phone and 4 antennas on the tower, and each antenna acts individually for <100Mbps per antenna. It is a separate feature that may be switched on or switched off at certain towers. A tower can be configured to use up to Rank 2, where only 2 antennas act individually and other antennas improve the experience. Only one antenna in a mobile phone may transmit, multiple may receive.
256QAM DL(downlink) and 64QAM UL(uplink) are additionally deployed. These allow the speed to improve even more, but cannot be used when the 4G signal isn't clear enough and will be automatically switched off in those cases.
Poor signal? 4TX may improve speeds even in cell edge conditions.
For 2CA (4G+), any of these frequencies may be aggregated in any way for downlink: B7(5MHz, 37/50/100Mbps), B7(20MHz, 150/200/400Mbps), B20(15MHz, 110/150Mbps).
Tested cell sites used 2TX for Band 20.
Not all of the speed may be visible to the user - if 256QAM and Rank 4 are used (391.656Mbps with no 4G+), speed may be 'spent on' extra FEC and retransmissions, both of which are necessary if the signal isn't perfect. Rank and/or modulation order may be lower if the signal isn't good enough.
These can only improve the speed between the tower and the mobile phone. Speeds between the tower and the website you're connecting to may be lower. An example of an AMBR value used is 500Mbps, but sometimes it's only a suggestion.
Very nice, now why is my network slow?
1) It depends on where you're located compared to the location and rotation of the tower's sectors. Sectors may tilt the airwaves down in addition to physically being rotated. This is an example that approximates how speeds may vary while connected to a sector aimed north, and with one other tower that uses the same frequencies.
Distance affects the signal. Obstacles inside the Fresnel zone affect the signal. Reflections and high speed affect the signal.
How antenna elements are placed (there are 10 "X"s in the example at the beginning of the page) and the rest of the design in the sector molds the emitted signal in a way that approximately flattens it. It goes further, but it's also vertically narrower. It is possible to be located where the signal isn't focused at. In addition to the main lobe, there are sidelobes.
Other towers that use the same frequencies cause interference during normal operation. Southeast and southwest sectors in that example cause interference as well.
2) It's only the speed between the tower and the mobile phone. Sometimes this has been favored over the speed between the tower and the rest of the network.
3) You share available resources with others. The resources to share are aimed north in that example.
Example: RRCConnectionReconfiguration
DL-DCCH-Message
message: c1 (0)
c1: rrcConnectionReconfiguration (4)
rrcConnectionReconfiguration
rrc-TransactionIdentifier: 0
criticalExtensions: c1 (0)
c1: rrcConnectionReconfiguration-r8 (0)
rrcConnectionReconfiguration-r8
measConfig
measObjectToRemoveList: 1 item
Item 0
MeasObjectId: 1
measObjectToAddModList: 2 items
Item 0
MeasObjectToAddMod
measObjectId: 1
measObject: measObjectEUTRA (0)
measObjectEUTRA
carrierFreq: 3075
allowedMeasBandwidth: mbw25 (2)
.... ..0. presenceAntennaPort1: False
neighCellConfig: The MBSFN subframe allocations of all neighbour cells are identical to or subsets of that in the serving cell (2)
Item 1
MeasObjectToAddMod
measObjectId: 2
measObject: measObjectEUTRA (0)
measObjectEUTRA
carrierFreq: 3200
allowedMeasBandwidth: mbw100 (5)
...0 .... presenceAntennaPort1: False
neighCellConfig: The MBSFN subframe allocations of all neighbour cells are identical to or subsets of that in the serving cell (2)
measCycleSCell-r10: sf160 (0)
reportConfigToRemoveList: 4 items
Item 0
ReportConfigId: 1
Item 1
ReportConfigId: 2
Item 2
ReportConfigId: 3
Item 3
ReportConfigId: 6
reportConfigToAddModList: 4 items
Item 0
ReportConfigToAddMod
reportConfigId: 1
reportConfig: reportConfigEUTRA (0)
reportConfigEUTRA
triggerType: event (0)
event
eventId: eventA3 (2)
eventA3
a3-Offset: 3dB (6)
...0 .... reportOnLeave: False
hysteresis: 1dB (2)
timeToTrigger: ms320 (8)
triggerQuantity: rsrp (0)
reportQuantity: both (1)
maxReportCells: 4
reportInterval: ms480 (2)
reportAmount: infinity (7)
Item 1
ReportConfigToAddMod
reportConfigId: 2
reportConfig: reportConfigEUTRA (0)
reportConfigEUTRA
triggerType: event (0)
event
eventId: eventA2 (1)
eventA2
a2-Threshold: threshold-RSRP (0)
threshold-RSRP: -112dBm (28)
hysteresis: 2dB (4)
timeToTrigger: ms640 (11)
triggerQuantity: rsrp (0)
reportQuantity: both (1)
maxReportCells: 1
reportInterval: ms5120 (6)
reportAmount: infinity (7)
Item 2
ReportConfigToAddMod
reportConfigId: 3
reportConfig: reportConfigEUTRA (0)
reportConfigEUTRA
triggerType: event (0)
event
eventId: eventA2 (1)
eventA2
a2-Threshold: threshold-RSRP (0)
threshold-RSRP: -126dBm (14)
hysteresis: 1dB (2)
timeToTrigger: ms40 (1)
triggerQuantity: rsrp (0)
reportQuantity: both (1)
maxReportCells: 1
reportInterval: ms480 (2)
reportAmount: infinity (7)
Item 3
ReportConfigToAddMod
reportConfigId: 4
reportConfig: reportConfigEUTRA (0)
reportConfigEUTRA
triggerType: event (0)
event
eventId: eventA1 (0)
eventA1
a1-Threshold: threshold-RSRP (0)
threshold-RSRP: -126dBm (14)
hysteresis: 1dB (2)
timeToTrigger: ms40 (1)
triggerQuantity: rsrp (0)
reportQuantity: both (1)
maxReportCells: 1
reportInterval: ms480 (2)
reportAmount: infinity (7)
measIdToRemoveList: 4 items
Item 0
MeasId: 1
Item 1
MeasId: 2
Item 2
MeasId: 3
Item 3
MeasId: 6
measIdToAddModList: 4 items
Item 0
MeasIdToAddMod
measId: 1
measObjectId: 1
reportConfigId: 1
Item 1
MeasIdToAddMod
measId: 2
measObjectId: 1
reportConfigId: 2
Item 2
MeasIdToAddMod
measId: 3
measObjectId: 2
reportConfigId: 3
Item 3
MeasIdToAddMod
measId: 4
measObjectId: 2
reportConfigId: 4
speedStatePars: release (0)
release: NULL
radioResourceConfigDedicated
mac-MainConfig: explicitValue (0)
explicitValue
drx-Config: setup (1)
setup
onDurationTimer: psf2 (1)
drx-InactivityTimer: psf30 (9)
drx-RetransmissionTimer: psf2 (1)
longDRX-CycleStartOffset: sf40 (3)
sf40: 5
timeAlignmentTimerDedicated: infinity (7)
mac-MainConfig-v1020
physicalConfigDedicated
pdsch-ConfigDedicated
p-a: dB0 (4)
soundingRS-UL-ConfigDedicated: release (0)
release: NULL
antennaInfo: explicitValue (0)
explicitValue
transmissionMode: tm4 (3)
codebookSubsetRestriction: n4TxAntenna-tm4 (3)
n4TxAntenna-tm4: ffffffffffffffff [bit length 64, 1111 1111 1111 1111 1111 1111 1111 1111 1111 1111 1111 1111 1111 1111 1111 1111 decimal value 18446744073709551615]
ue-TransmitAntennaSelection: release (0)
release: NULL
schedulingRequestConfig: setup (1)
setup
sr-PUCCH-ResourceIndex: 33
sr-ConfigIndex: 5
[Periodicity: 10]
[Subframe Offset: 0]
dsr-TransMax: n64 (4)
cqi-ReportConfig-r10
cqi-ReportAperiodic-r10: setup (1)
setup
cqi-ReportModeAperiodic-r10: rm31 (4)
aperiodicCSI-Trigger-r10
trigger1-r10: 40 [bit length 8, 0100 0000 decimal value 64]
trigger2-r10: c0 [bit length 8, 1100 0000 decimal value 192]
nomPDSCH-RS-EPRE-Offset: 0dB (0)
cqi-ReportPeriodic-r10: setup (1)
setup
cqi-PUCCH-ResourceIndex-r10: 18
cqi-pmi-ConfigIndex: 83
cqi-FormatIndicatorPeriodic-r10: widebandCQI-r10 (0)
widebandCQI-r10
ri-ConfigIndex: 322
...0 .... simultaneousAckNackAndCQI: False
csi-ConfigIndex-r10: release (0)
release: NULL
csi-SubframePatternConfig-r10: release (0)
release: NULL
pucch-ConfigDedicated-v1020
pucch-Format-r10: format3-r10 (0)
format3-r10
n3PUCCH-AN-List-r13: 4 items
Item 0
n3PUCCH-AN-List-r13 item: 0
Item 1
n3PUCCH-AN-List-r13 item: 1
Item 2
n3PUCCH-AN-List-r13 item: 2
Item 3
n3PUCCH-AN-List-r13 item: 3
cqi-ReportConfigPCell-v1250
altCQI-Table-r12: allSubframes (0)
nonCriticalExtension
nonCriticalExtension
otherConfig-r9
reportProximityConfig-r9
nonCriticalExtension
sCellToAddModList-r10: 1 item
Item 0
SCellToAddMod-r10
sCellIndex-r10: 1
cellIdentification-r10
physCellId-r10: 299
dl-CarrierFreq-r10: 3200
radioResourceConfigCommonSCell-r10
nonUL-Configuration-r10
dl-Bandwidth-r10: n100 (5)
antennaInfoCommon-r10
antennaPortsCount: an4 (2)
phich-Config-r10
phich-Duration: normal (0)
phich-Resource: one (2)
pdsch-ConfigCommon-r10
referenceSignalPower: 16 dBm
p-b: 1
radioResourceConfigDedicatedSCell-r10
physicalConfigDedicatedSCell-r10
nonUL-Configuration-r10
antennaInfo-r10
transmissionMode-r10: tm4 (3)
codebookSubsetRestriction-r10: 00000000ffffffff [bit length 64, 0000 0000 0000 0000 0000 0000 0000 0000 1111 1111 1111 1111 1111 1111 1111 1111 decimal value 4294967295]
ue-TransmitAntennaSelection: release (0)
release: NULL
pdsch-ConfigDedicated-r10
p-a: dB-3 (2)
ul-Configuration-r10
cqi-ReportConfigSCell-r10
cqi-ReportModeAperiodic-r10: rm31 (4)
nomPDSCH-RS-EPRE-Offset-r10: 0dB (0)
cqi-ReportConfigSCell-v1250
altCQI-Table-r12: allSubframes (0)