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Signal analyzer LTE
4G LTE (Long-Term Evolution) is a fourth-generation mobile communication technology developed by the 3rd Generation Partnership Project (3GPP). It was designed to provide higher data rates, lower latency, improved spectral efficiency, and greater network capacity compared to earlier technologies such as UMTS.
LTE uses OFDMA in the downlink to divide the available radio spectrum into multiple orthogonal subcarriers. These subcarriers are allocated dynamically to users according to their traffic requirements and radio-channel conditions.
Typical bandwidths of LTE downlink channel are 1.4, 3, 5, 10, 15, 20 MHz.
LTE analyzer searches for LTE cells, decodes synchronization and broadcast information, and estimates recent downlink air load.
- PCI - Physical Cell ID. Radio-layer cell identity, not globally unique.
- PLMN - Public Land Mobile Network, shown as MCC-MNC.
- Country / Operator - resolved from the embedded PLMN database.
- TAC - Tracking Area Code.
- Cell ID - E-UTRAN Cell ID from SIB1.
- Band - LTE operating band advertised by SIB1.
- BW - decoded LTE channel bandwidth.
- Ports - CRS antenna ports advertised by MIB.
- Air load - estimated occupied PRBs in the current downlink carrier.
- PSS / SSS - synchronization-signal quality.
- CFO - carrier frequency offset.
- MIB - Master Information Block status.
- SIB1 - System Information Block 1 status.
The session status panel may show MIB, SIB1 CFI, PDCCH, DCI, PDSCH, TB CRC and ASN.1 steps.
- CFI - Control Format Indicator.
- PDCCH - Physical Downlink Control Channel.
- DCI - Downlink Control Information.
- PDSCH - Physical Downlink Shared Channel.
- TB - Transport Block.
- CCE - Control Channel Element.
- MCS - Modulation and Coding Scheme.
- RV - Redundancy Version.
- ASN.1 - protocol data structure encoding used by system information.
- Physical Cell ID - radio-layer identity.
- PSS / SSS quality - synchronization quality for this PCI.
- Frequency offset - estimated tuning error relative to this cell.
- Channel bandwidth - bandwidth decoded from MIB.
- Antenna ports - CRS antenna ports advertised by the cell.
- System frame number - radio-frame timing from MIB.
- PLMN - public network identifier.
- Tracking Area Code - idle-mode mobility and paging area.
- E-UTRAN Cell ID - cell identity broadcast in SIB1.
- Cell access - whether ordinary UE access is barred or available.
- SI schedule - schedule for remaining system information.
- Paging cycle - paging occasion cycle from SIB2.
- RACH - Random Access Channel.
- Random-access preambles - number of contention-based RACH signatures.
- PRACH configuration - time/frequency placement for initial uplink access.
- PRACH root sequence - root used to construct random-access preambles.
- Reference signal power - nominal CRS transmit power signalled by the cell, not received signal strength.
- PUSCH - Physical Uplink Shared Channel.
- PUSCH 64QAM - whether 64QAM is allowed on uplink.
- EARFCN - E-UTRA Absolute Radio Frequency Channel Number.
- P0 nominal PUSCH - open-loop uplink power-control reference.
- Cell reselection priority - priority assigned to the serving LTE frequency.
- Minimum received level - SIB3 minimum level used for cell-selection criteria.
- Serving-low threshold - threshold for leaving a low-priority serving frequency.
- Hysteresis - margin that reduces repeated reselection between similar cells.
- Reselection timer - condition must persist for this interval before reselection.
Air load is a radio-resource occupancy estimate. It is not BTS CPU load, backhaul load, user count or guaranteed throughput. Co-channel cells on the same frequency are measured as combined radio energy.