LTE Troubleshooting / Optimization Guidelines
Sprint 4G LTE Troubleshooting and Optimization Guidelines Document Version 2.0
4G National RF Engineering
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LTE Troubleshooting / Optimization Guidelines
Revisions and Contributions
Organization Network Engineering Network Engineering (Dir) Network Engineering (Mgr)
Author Geof Lubeskie Geof Lubeskie
Version 1.0 2.0
Name Greg O’Connor Hui-Lin Chang Rashmi Kumar
Date November 2013
E-mail Address
[email protected] om
January 2013
[email protected] om
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Table of Contents 1
General......................................................................................................................... 1.1 1.2 1.3
2
LTE Optimization Process Flows........................................................................... 2.1 2.2 2.3
3
Cell Selection Process...................................................................................................................9 Cell Selection Criteria...................................................................................................................9 Cell Reselection..........................................................................................................................10
Interference Control...............................................................................................12 LTE Handoff Optimization....................................................................................13 6.1 6.2
7 8
RSRP.............................................................................................................................................8 SINR..............................................................................................................................................8
Cell Selection.............................................................................................................. 4.1 4.2 4.3
5 6
Site Level Optimization........................................................................................................5 Cluster Level Optimization..................................................................................................6 Market level Optimization...................................................................................................7
RF Conditions............................................................................................................. 3.1 3.2
4
Purpose.......................................................................................................................................4 Responsibility...........................................................................................................................4 Revision History......................................................................................................................4
Active mode handover................................................................................................................13 Idle mode handover.....................................................................................................................16
EUTRAN and CDMA2000 Handover..................................................................16 RAN Parameters......................................................................................................20 8.1 8.2
Physical Cell Identity..................................................................................................................20 Root Sequence Index (RSI).........................................................................................................20
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1 General 1.1
Purpose The purpose of this document is to provide national and local RF guidelines to troubleshoot and optimize Sprint’s 4G Network. This document will be used by Sprint RF Engineering to understand high level network performance metrics.
1.2
Responsibility The 4G National RF Performance Engineering team is responsible for updating, and monitoring the application of the guidelines described in this document. Please contact the following, if there are questions regarding these planning guidelines. Geoff Lubeskie, National RF Planning and Engineering (717-344-1869)
[email protected] Dusty Wyman (703-376-4463) Manager RF Planning and Engineering
[email protected] Rashmi Kumar (703-433-4358) Manager RF Planning and Engineering
[email protected]
1.3
Revision History Date
Version
11/15/201 3
1.0
Document Owner Geoff Lubeskie
Comments Original document (1st Draft)
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LTE Troubleshooting / Optimization Guidelines
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LTE Troubleshooting / Optimization Guidelines
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LTE Optimization Process Flows LTE troubleshooting / optimization activities can be separated into 3 distinct levels:
Site Level Cluster Level Market Level
At the very start, eNBs are the foundation of all LTE Networks. Contiguous groups of eNBs form clusters and groups of clusters make up the markets.
Figure 1: Network Optimization Flowchart
2.1 Site Level Optimization Single site verification, the first phase of network optimization, involves function verification at each new site. Single site verification aims to ensure that each site is properly installed and that parameters are correctly
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LTE Troubleshooting / Optimization Guidelines
configured according to the Golden Image (GI). A link to the latest GI for all OEMS can be found at the link below. http://sprintcommunities.corp.sprint.com/sites/cops/4GRFPerformance/Parameter %20Management/Forms/AllItems.aspx?RootFolder=%2Fsites%2Fcops%2F4GRFPerformance %2FParameter%20Management%2FGolden%20Parameters%2FGolden%20Params Key Performance Indicators (KPIs) ensure each site is performing as it should be. At the very minimum the engineer should validate and analyze the following metrics to ensure that the eNB is performing as it should be. It should be mentioned that each OEM has their own specific targets for each KPI and should be referenced when analyzing the data.
Average & Peak download Throughput Average & Peak upload Throughput Intra eNB handovers (between sectors) Inter eNB handovers to first tier neighbors Connection setup time & Connection success rate Latency Validate RSRP, CINR, Rx Power, and Tx Power are as expected for the test location
2.2 Cluster Level Optimization Contiguous coverage between eNBs within a cluster ensures seamless mobility; therefore, this optimization activity is a major factor in overall network accessibility and retainability. As of the writing of this documentation there is no baseline of the Sprint LTE network. It is imperative that when the OEMs submit clusters for acceptance that the local RF teams are involved. Local RF teams should create MapInfo files for each cluster, which show areas for future optimization.
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LTE Troubleshooting / Optimization Guidelines
Figure 2: Mapinfo file created by local RF showing areas for future optimization
A cluster drive route must be carefully designed to cover each sector of all sites so that all major highways, roads, Sprint stores and major customer locations are covered. Analysis of the drive data will show areas for potential optimization changes to improve the overall user experience. All changes made during the optimization phase should be documented for future reference and possibly shared with other markets as a means of best practice. A major challenge that the engineer will face is the fact that the 4G and 3G networks are using the same antenna. At this time, voice is still the number one revenue source for Sprint; therefore, optimization efforts on the 4G sites should not negatively impact the underlying 3G network. As in Site level optimization at the very minimum the engineer should verify the following KPIs during Cluster Optimization
Average & Peak download Throughput Average & Peak upload Throughput Intra eNB handovers (between sectors) Inter eNB handovers to first tier neighbors Connection setup time & Connection success rate Latency Validate RSRP, CINR, Rx Power, and Tx Power are as expected for the test location
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2.3 Market level Optimization Similar to cluster level optimization, multiple subsets are looked at as a whole. Here, several clusters should be evaluated and analyzed as a whole to verify that mobility and proper networking exists. The on-going evolution of the network due to the addition of new macro, micro, Pico and in-building sites requires that the engineer continuously look at optimizing the network to meet the demands of capacity, and customer expectations.
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RF Conditions
3.1
RSRP
Reference signal received power (RSRP), is determined for a considered cell as the linear average over the power contributions (in [W]) of the resource elements that carry cell-specific reference signals within the considered measurement frequency bandwidth. Note: Different from GSM or TD-SCDMA systems, TD-LTE systems have multiple subcarriers multiplexed. Therefore, the measured pilot signal strength is the RSRP of a single subcarrier (15 kHz) not the total bandwidth power of the frequency. If receiver diversity is in use by the UE, the reported value shall not be lower than the corresponding RSRP of any of the individual diversity branches The RSRPs near a cell, in the middle of a cell, and at the edge of a cell are determined based on the distribution of signals on the entire network. Generally, the RSRP near a cell is -85 dBm, the RSRP in the middle of a cell is -95 dBm, and the RSRP at the edge of a cell is -105 dBm.
3.2
SINR
The SINR is not specifically defined in 3GPP specifications. A common formula is as follows: SINR = S/(I + N) S: indicates the power of measured usable signals. Reference signals (RS) and physical downlink shared channels (PDSCHs) are mainly involved.
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LTE Troubleshooting / Optimization Guidelines
I: indicates the power of measured signals or channel interference signals from other cells in the current system and from inter-RAT cells. N: indicates background noise, which is related to measurement bandwidths and receiver noise coefficients.
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Cell Selection
The cell selection process and cell selection criteria as per 3GPP standard 36.304 are:
4.1
Cell Selection Process
The UE shall use one of the following two cell selection procedures: 1. Initial Cell Selection This procedure requires no prior knowledge of which RF channels are E-UTRA carriers. The UE shall scan all RF channels in the E-UTRA bands according to its capabilities to find a suitable cell. On each carrier frequency, the UE need only search for the strongest cell. Once a suitable cell is found this cell shall be selected. 2. Stored Information Cell Selection This procedure requires stored information of carrier frequencies and optionally also information on cell parameters, from previously received measurement control information elements or from previously detected cells. Once the UE has found a suitable cell the UE shall select it. If no suitable cell is found the Initial Cell Selection procedure shall be started. NOTE: Priorities between different RAT or frequencies provided to the UE by system information or dedicated signaling are not used in the cell selection process.
4.2
Cell Selection Criteria
The cell selection criterion S is fulfilled when: Srxlev > 0 Where: Srxlev = Qrxlevmeas –(Qrxlevmin –Qrxlevminoffset) -Pcompensation Where: The signaled value QrxlevminOffset is only applied when a cell is evaluated for cell selection as a result of a periodic search for a higher priority PLMN while camped Privileged & Confidential Information This information is subject to Sprint policies regarding use and is the property of Sprint and/or its relevant affiliates and may contain restricted, confidential or privileged materials intended for the sole use of the intended recipient. Any review, use, distribution or disclosure is prohibited without authorization
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LTE Troubleshooting / Optimization Guidelines
normally in a VPLMN [5]. During this periodic search for higher priority PLMN the UE may check the S criteria of a cell using parameter values stored from a different cell of this higher priority PLMN. Srxlev Cell Selection RX level value (dB) Qrxlevmeas Measured cell RX level value (RSRP). Qrxlevmin Minimum required RX level in thecell (dBm) Qrxlevminoffset Offset to the signalled Qrxlevmin taken into account in the Srxlev evaluation as a result of a periodic search for a higher priority PLMN while camped normally in a VPLMN [5] Pcompensation [FFS]
4.3
Cell Reselection
Cell reselection parameters are broadcast in system information and are read from the serving cell as follows: Qoffsets,n Qoffsetfrequency Qhyst Qrxlevmin TreselectionRAT
This specifies the offset between the two cells. Frequency specific offset for equal priority E-UTRAN frequencies. This specifies the hysteresis value for ranking criteria. This specifies the minimum required Rx level in the cell in dBm. This specifies the cell reselection timer value. For each target RAT a specific value for the cell reselection timer isdefined, which is applicable when evaluating reselection within E-UTRAN or towards other RAT (i.e. TreselectionRATfor E-UTRAN is TreselectionEUTRAN, for UTRAN TreselectionUTRAN for GERAN TreselectionGERAN, forTreselectionCDMA_HRPD, and for TreselectionCDMA_1xRTT).Note: TreselectionRAT is not sent on system information, but used in
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reselection rules by the UE for each RAT. TreselectionEUTRAN TreselectionUTRAN TreselectionGERAN TreselectionCDMA_HRPD TreselectionCDMA_1xRTT Threshx, high
Threshx, low
Threshserving, low
This specifies the cell reselection timer value TreselectionRAT forEUTRAN This specifies the cell reselection timer value TreselectionRAT for UTRAN This specifies the cell reselection timer value TreselectionRAT for GERAN This specifies the cell reselection timer value TreselectionRAT for CDMA HRPD This specifies the cell reselection timer value TreselectionRAT for CDMA 1xRTT This specifies the threshold used by the UE when reselecting towards the higher priority frequencyX than currentlyserving frequency. Each frequency of EUTRAN and UTRAN, each band of GERAN, each band class of CDMA2000HRPD and CDMA2000 1xRTT will have a specific threshold. This specifies the threshold used in reselection towards frequencyX priority from a higher priority frequency. Eachfrequency of EUTRAN and UTRAN, each band of GERAN, each band class of CDMA2000 HRPD and CDMA20001xRTT will have a specific threshold. This specifies the threshold for serving frequency used in reselection evaluation towards lower priority E-UTRANfrequency or
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RAT. Sintrasearch Snonintrasearch TCRmax NCR_M NCR_H TCRmaxHyst
This specifies the threshold (in dB) for intra frequency measurements. This specifies the threshold (in dB) for EUTRAN inter-frequency and inter-RAT measurements. This specifies the duration for evaluating allowed amount of cell reselection(s). This specifies the maximum number of cell reselections to enter medium mobility state. This specifies the maximum number of cell reselections to enter high mobility state. This specifies the additional time period before the UE can enter normal-mobility.
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5
Interference Control
Downlink (DL) inter cell interference which reduces the signal quality is a major factor contributing to degraded service. It usually impacts cell-edge users which lack good quality RF signal due to the presence of multiple serving sectors of similar signal strength. DL inter-cell interference scenario can also be observed in dense urban areas where multipath factor can results in strong signals from various sectors in one geographic region. DL interference if not corrected can lead to poor throughput performance on both downlink and uplink. Therefore an improved DL coverage in terms of both signal strength and quality provides better user experience. Indicators such as low Signal to noise ratio (SINR), low scale Channel quality indicator (CQI), Transmission mode (transmit diversity), low Reference Signal Received Quality (RSRQ) and high Block error rate (BLER) are common indicators of DL interference. Low SINR and low CQI reports result in lower and more robust modulation scheme for data transmission. The first step in optimization efforts is to improve the coverage and quality of existing serving cells resulting in good quality of service (QoS). RSRQ is defined in TS 36.214 as: Reference Signal Received Quality (RSRQ) is defined as the ratio N×RSRP/(E-UTRA carrier RSSI), where N is the number of RB’s of the E-UTRA carrier RSSI measurement bandwidth. The measurements in the numerator and denominator shall be made over the same set of resource blocks. E-UTRA Carrier Received Signal Strength Indicator (RSSI), comprises the linear average of the total received power (in [W]) observed only in OFDM symbols containing reference symbols for antenna port 0, in the measurement bandwidth, over N number of resource blocks by the UE from all sources, including co-channel serving and non-serving cells, adjacent channel interference, thermal noise etc. The reference point for the RSRQ shall be the antenna connector of the UE. If receiver diversity is in use by the UE, the reported value shall not be lower than the corresponding RSRQ of any of the individual diversity branches. Other than general optimization practices to control interference, LTE also offers features such as ‘Inter cell Interference Coordination (ICIC)’ technique which dynamically controls interference based on UE’s CQI reports. Privileged & Confidential Information This information is subject to Sprint policies regarding use and is the property of Sprint and/or its relevant affiliates and may contain restricted, confidential or privileged materials intended for the sole use of the intended recipient. Any review, use, distribution or disclosure is prohibited without authorization
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Downlink ICIC (DL-ICIC) enhances cell-edge UE performance by adjusting the power for UE based on reported channel condition. Cell center users get different power allocation based on UE’s feedback. Average CQI Threshold metric is used to differentiate cell edge and cell center users. DL power control mechanism uses the channel estimation to adjust the Pa parameter which leads to: If the user is estimated to be in cell center condition, UE specific DL power related parameter Pa is lowered, which results in power reduction of data subcarriers for that UE and further decreases interference to neighboring cells
If UE is estimated to be in cell center condition, Pa is increased and hence data subcarriers power is increased to maintain edge UE‟s quality
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LTE Handof Optimization
Handover success rate is another important KPI focused on in optimization process. Having a good success rate indicates that sites in network connect to each and user can enjoy uninterrupted access to network in mobility scenarios. The impact of LTE handover performance depends on what type of applications users are running at their end. For example, poor handover performance or high handover latency have low impact on applications such as file transfer where a small interruption can be tolerable whereas bad handover performance may have severe impact on VOIP applications where a handover drop results in voice call drop.
6.1
Active mode handover
Active mode handover can be of three different types:
1. Intra/Inter Frequency – Handover between cells using sane or different center frequencies 2. Intra/Inter eNB – Handover between cells of the same or different site 3. S1/X2 based – Handover involving MME interaction or directly between two eNBs using X2 links Privileged & Confidential Information This information is subject to Sprint policies regarding use and is the property of Sprint and/or its relevant affiliates and may contain restricted, confidential or privileged materials intended for the sole use of the intended recipient. Any review, use, distribution or disclosure is prohibited without authorization
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UE can be configured in connected state to report several different types of measurements based on event types as explained below.
Event A1
Serving becomes better than a threshold
Used to deactivate Gap Measurements
Event A2
Serving becomes worse than a threshold
Used to activate Gap Measurements
Event A3
Neighbor becomes offset better than the Serving
Used to trigger Intra-FA Handoff
Event A4
Neighbor becomes better than a threshold
Used for ANR
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Next section discusses the configuration related to Event A3 which is used to facilitate Intra-FA LTE handover.
In active mode measurements are performed only when Serving Cell RSRP falls below a configurable threshold (Smeasure) • The A3 event parameters for Active mode measurement are transmitted via RRC Connection Reconfiguration Message • The parameter a3offsetdefines the (neighbor + offset > serving) criteria. • Additionally, there is a cell individual offset that can be configured per neighbor (Ind_offset). • This criterion must be satisfied over a configurable period of time for the measurement report to be done (TimeToTrigger). • The measurement criteria can be based on RSRP or RSRQ and is configurable (TriggerQuantity). • The measurement report can be configured to report RSRP/RSRQ or both (ReportQuantity).
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• Periodic reports can be generated after the Event criteria are met based on a configurable parameter (reportInterval). • Number of reports generated based on the event is controlled using a configurable parameter (reportAmount)
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6.2
Idle mode handover
Idle mode handover or cell reselection is the process used by UE and network to monitor UE’s location without it requiring radio resources. In Idle mode, UE remains attached at MME level but remains RRC idle unless it requires RRC resources (for e.g. To perform TAU or Paging procedures) Maintaining most current and updated neighbor list on the eNBs is critical to facilitate successful handover. Neighbor list must be updated frequently to accommodate addition of new sites and sectors in the network. Condition where multiple handovers are recorded within a very short period between same two cells in stationary or mobile scenario is known as Ping-Pong. Ping-Pong condition affects the end user as more processing time results in poor user experience. This situation arises when both source and target sectors meet the handover thresholds and are equivalent in signal strength. Ping-Pong can occur in both strong and weak conditions. A3 offset, S-measure, Hysteresis and Cell individual offset are some parameters which can be tweaked to reduce Ping-Pong rate.
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EUTRAN and CDMA2000 Handover
EUTRAN and CDMA2000 handover can be useful when both networks are overlaid on same geographical region. A user traveling out of LTE coverage area can hand down to HRPD while maintaining the same data session and uninterrupted data transfer. This feature is helpful in cases where a new LTE network is deployed on a matured CDMA2000 network and UE can rely on underlying network whenever it goes out of coverage on LTE Implementation of Neighbor list for underlying CDMA network is needed to facilitate EUTRAN to CDMA2000 handover. On LTE side, appropriate neighboring sectors with PN and channel information are populated. Right HRPD neighbors can be selected based statistics such as Handover matrix (HOM) data of CDMA network. Optimization drive test can also give useful information in defining missing or appropriate neighbors for EUTRAN to CDMA2000 interworking. Below table explains Parameters and Events used on EUTRAN to CDMA2000 interworking: Message RRC Connection Reconfiguration
IE B2 Event
Parameter b2Threshold1Rsrp
Description RSRP threshold1 used for triggering the EUTRA measurement report for CDMA2000 HRPD Event B2.
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b2Threshold1Rsrq
RRC Connection Reconfiguration
b2Threshold2Cdma200 0
RSRQ threshold1 used for triggering the EUTRA measurement report for CDMA2000 HRPD Event B2. CDMA2000 threshold 2 used for triggering the inter-RAT CDMA2000 measurement report for CDMA2000 HRPD Event B2.
qOffsetFreq hysteresisB2 timeToTriggerB2
reportIntervalB2 reportAmountB2 maxReportCellsB2
triggerQuantityB2
RRC Connection Reconfiguration
A2 Event
a2ThresholdRsrp
a2ThresholdRsrq
reportIntervalA2
Hysteresis applied to entry and leave condition of CDMA2000 HRPD Event B2. timeToTrigger value for CDMA2000 HRPD Event B2. The timeToTrigger value is the period of time that must be met for the UE to trigger a measurement report. The reporting interval of a measurement report for CDMA2000 HRPD Event B2. The number of measurement reports for CDMA2000 HRPD Event B2. The maximum number of cells included in a measurement report for CDMA2000 HRPD Event B2. Quantity that triggers the Event B2 measurement The trigger can be set for either RSRP or RSRQ and is only applicable on threshold 1. A2 event is triggered when source becomes worse than the configured RSRP threshold (Refer to standard 36.133 for RSRP Report mapping) Primary RSRQ threshold value for eventA2. Used only when triggerQuantityA2Prim is set to RSRQ. Determines the reporting interval of a measurement
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report for Event triggerQuantityA2
A1 event is triggered when source becomes worse than the configured RSRQ threshold (Refer to standard 36.133 for RSRQ Report Mapping.
hysteresisA2
Hysteresis applied to entry and leave conditions of Event A2 The timeToTrigger value is the period of time that must be met for the UE to trigger a measurement report for Event A2 The number of reports for periodical reporting for the primary eventA2 measurement .Value 0 means that reports are sent as long as the event is fulfilled. Primary and secondary measurement parameters refer to the option to use different settings for two simultaneous measurements for eventA2. The maximum number of cells included in a measurement report for Event A2. Determines whether the Measurement report for A2 event includes both RSRP and RSRQ information or the only RSRP or RSRQ as configured by the Trigger event above. Filtering coefficient used by the UE to filter RSRP measurements before event evaluation The measurement filter averages a number of measurement report values to filter out the impact of large scale fast fading.
timeToTriggerA2
reportAmountA2
maxReportCellsA2 reportQuantityA2
filterCoefficientEUtraRs rp
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RRC Connection Reconfiguration
A1 Event
filterCoefficientEUtraRs rq
Filtering coefficient used by the UE to filter RSRQ measurements before event evaluation The measurement filter averages a number of measurement report values to filter out the impact of large scale fast fading.
a1ThresholdRsrp
A1 event is triggered when source becomes better than the configured RSRP threshold ( Actual Threshold= Parameter -140, 36.133 standards) dBm
a1ThresholdRsrq
A1 event is triggered when source becomes better than the configured RSRQ threshold (Refer to 36.133 standard for RSRP Report mapping) Determines whether Event A1 is triggered based on RSRP or RSRQ criteria. Determines whether the Measurement report for A1 event includes both RSRP and RSRQ information or the only RSRP or RSRQ as configured by the Trigger event above. The maximum number of cells included in a measurement report for Event A1. Hysteresis applied to entry and leave conditions of Event A1. The timeToTrigger value is the period of time that must be met for the UE to trigger a measurement report for Event A1 Determines the reporting interval of a measurement report for Event A1 Determines the number of measurement reports UE
triggerQuantityA1 reportQuantityA1
maxReportCellsA1 hysteresisA1 timeToTriggerA1
reportIntervalA1 reportAmountA1
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needs to send when Event A1 criteria is met SIB8
systemTim eInfo CellReselec tion Parameters CDMA 2000
timieAndPahseSynchCri tical
bandClass
cellReselectionPriority
threshXHigh threshXLow tReselectionSfUsageHR PD
tReselectionHRPD
tReselectionSfHighHRP D
tReselectionSfMediumH RPD searchWindowSize
Identifies the CDMA-eHRPD frequency band class in which the carrier frequency can be found Reselection priority of the cell in the eNB. The range is 0-7, where 0 indicates low, and 7 high in priority. ThreshXHigh of CDMA2000 HRPD band class DB. ThreshXLow of CDMA2000 HRPD band class DB. Whether to use tReselectionSfUsageHRPD of HRPD reselection information that is sent down to SIB8. tReselectionSfUsageHRPD determines whether to apply a scaling factor for HRPD cell reselection. TReselctionHRPD included in the HRPD Reselection information sent to SIB8. The default is 0, and can be changed by the operator. Value by which parameter tReselectionCdmaHrpd is multiplied if the UE is in a high mobility state as defined in 3GPP TS 36.304 TReselectionSfMediumHRPD included in the HRPD Reselection information sent to SIB8. The size of the search window in the eNB.
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8
RAN Parameters
8.1 Physical Cell Identity PCI is derived from two physical layer signals –Primary Synchronization Signal (PSS) and Secondary synchronization signal (SSS). There are 504 unique PCIs. The physical-layer cell identities are grouped into 168 unique physical-layer cellidentity groups, each group containing three unique identities. The grouping is such that each physical-layer cell identity is part of one and only one physical-layer cell-identity group. A physical-layer cell identity is thus uniquely defined by a number in the range of 0 to 167, representing the physical-layer cell-identity group, and a number in the range of 0 to 2, representing the physical-layer identity within the physical-layer cell-identity group.(2) ID (1) ID cell ID 3N N N (1) ID N (2) ID N Each cells Reference signal transmits a pseudo random sequence corresponding to assigned PCI. And channel quality measurements are also made on reference signals. Thus, an optimized allocation of PCIs is needed to avoid problems in cell recognition or cell search. During PCI planning, one needs to avoid same PCI and PSS on neighboring cell. This eliminates confusion in cell search and also reduces interference which can occur due to PSS or reference signal collision.
8.2 Root Sequence Index (RSI) The Preambles used in RACH procedure are derived from Root Sequence. Preambles are obtained by cyclic shifts of root sequence which are based on Zadoff-Chu sequence. There are 838 Root Sequences available. There are 64 preambles available per cell and UE randomly selects one preamble to perform random access procedure. If number of preambles per root sequence is less than 64 Preambles, continue deriving Preambles with next Root Sequence unit 64 preambles are obtained. Thus, unique assignment of Root sequence is recommended between neighboring cells. The Below tables describes Ncs to Zero Correlation zone configuration mapping and LSM parameter for configuring RSI and Zero correlation zone configuration parameter.
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LTE Troubleshooting / Optimization Guidelines
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LTE Troubleshooting / Optimization Guidelines
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References
https://Systems.samsungwireless.com Network Vision > Publications > Sprint > 4G RAN > Manuals
430 LTE eNB Maintenance Troubleshooting Manual 410 MMBS Operational Manual 819 LTE Optimization Guidelines LTE standard documents: 3GPP TS 36 series LTE optimization guidelines Huawei Technologies LTE Optimization Guidelines Anritsu
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