Cellular terminology

A glossary of the cellular terms used in Network Survey.

Network types

GSM (Global System for Mobile Communications)

2G cellular technology
Circuit-switched voice and data
Being phased out globally
Max speed: about 384 Kbps (EDGE)

CDMA (Code Division Multiple Access)

2G/3G cellular technology
Primarily used in North America
Mostly retired as of 2024
Max speed: about 3.1 Mbps (EV-DO Rev A)

UMTS (Universal Mobile Telecommunications System)

3G cellular technology
Also called WCDMA
Being retired in favor of LTE/NR
Max speed: about 42 Mbps (HSPA+)

LTE (Long Term Evolution)

4G cellular technology
Most common as of 2024
Packet-switched IP network
Max speed: about 1 Gbps (LTE-Advanced Pro)

NR (New Radio)

5G cellular technology
Latest generation
Low/mid/high band (mmWave)
Max speed: 10+ Gbps

Identifiers

MCC (Mobile Country Code)

3-digit country identifier
Examples: 310-316 (USA), 234 (UK), 404 (India)
Used globally to identify country

MNC (Mobile Network Code)

2 or 3 digit carrier identifier
Combined with MCC to identify network
Examples: 260 (T-Mobile USA), 410 (AT&T)
Previously represented as an integer, which lost leading zeros

PLMN (Public Land Mobile Network)

Combined MCC + MNC identifier
Format: “MCC-MNC” (e.g., “310-01”, “234-15”)
Uniquely identifies a mobile network worldwide
Preserves MNC leading zeros (unlike separate integer fields)
Used in Network Survey messages and CSV files

Cell ID / CID / ECI / NCI

Unique identifier for a cell
GSM/UMTS: CID
LTE: ECI (28-bit)
NR: NCI (36-bit)
Globally unique when combined with MCC/MNC

LAC (Location Area Code)

GSM/UMTS location grouping
Group of cells for paging
16-bit value (0-65535)

TAC (Tracking Area Code)

LTE/NR location grouping
Equivalent to LAC for 4G/5G
16-24 bit value

PCI (Physical Cell ID)

LTE: 0-503
NR: 0-1007
Not globally unique
Used for radio layer identification

PSC (Primary Scrambling Code)

UMTS physical layer identifier
0-511
Similar to PCI for 3G

BSIC (Base Station Identity Code)

GSM physical layer identifier
0-63
NCC (3 bits) + BCC (3 bits)

Signal measurements

RSSI (Received Signal Strength Indicator)

Total received power
Measured in dBm
Includes signal + noise + interference
Less specific than RSRP/RSCP

RSRP (Reference Signal Received Power)

LTE reference signal power
Measured in dBm
Range: -140 to -44 dBm
Primary LTE signal metric
App colors: Strong above -85 dBm, Good -85 to -95, Fair -95 to -105, Weak -105 to -115, Very weak below -115

RSRQ (Reference Signal Received Quality)

LTE signal quality indicator
Measured in dB
Range: -19.5 to -3 dB
Indicates interference/congestion
App colors: Strong -10 dB or better, Good -11 to -13, Fair -14 to -16, Weak -17 to -19, Very weak -20 or worse

SNR / RSSNR (Signal-to-Noise Ratio)

LTE signal clarity
Measured in dB
Range: -20 to +30 dB
App colors: Strong 20 dB or better, Good 13 to 19, Fair 5 to 12, Weak 0 to 4, Very weak below 0

SS-RSRP (Synchronization Signal RSRP)

5G NR reference signal power
Similar to LTE RSRP
Range: -156 to -31 dBm
App colors: the same steps as LTE RSRP

SS-RSRQ (Synchronization Signal RSRQ)

5G NR signal quality
Similar to LTE RSRQ
Range: -43 to 20 dB
App colors: the same steps as LTE RSRQ

SS-SINR (Synchronization Signal SINR)

5G NR signal relative to interference and noise
Range: -23 to 40 dB
App colors: the same steps as LTE SNR

RSCP (Received Signal Code Power)

UMTS signal power
Measured in dBm
App colors: Strong above -75 dBm, Good -75 to -85, Fair -85 to -95, Weak -95 to -105, Very weak below -105 (GSM and UMTS RSSI use the same steps)

Frequency channels

ARFCN (Absolute Radio Frequency Channel Number)

GSM frequency channel number
Maps to specific frequency
Example: ARFCN 123 = specific MHz

UARFCN (UMTS ARFCN)

UMTS frequency channel number
Example: 10700 = Band 1 (2100 MHz)

EARFCN (E-UTRA ARFCN)

LTE frequency channel number
Maps to specific band and frequency
Example: 1300 = Band 3 (1800 MHz DL)

NARFCN (NR ARFCN)

5G NR frequency channel number
Example: 126400 = n71 (600 MHz)

Tower components

eNB / eNodeB (Evolved NodeB)

LTE cell tower / base station
Handles radio communications
Calculated from ECI (first 20 bits)

gNB / gNodeB (Next Generation NodeB)

5G NR cell tower / base station
Calculated from NCI (first 22-32 bits)

Sector / Cell

Individual radio panel on tower
Typically 3 sectors per tower (120° each)
Can be 6 sectors (60° each) or omni (single)
LTE Sector ID: the last 8 bits of the ECI

Serving Cell

Cell your phone is registered on
Active communication link
Shown on the Serving cell card of the Cellular view

Secondary Serving Cell

An extra cell the phone uses alongside its primary cell
On 5G NSA, the NR cell that carries data while the phone is registered on an LTE anchor
Shown on the 5G NR secondary cell card; records mark it as secondary serving

Neighbor Cell

Nearby cells detected but not connected
Used for handover decisions
Multiple neighbor cells visible

Network parameters

TA (Timing Advance)

Distance measure to tower
LTE: 0-1282
NR: reported in microseconds, on Android 14 and later
Larger value = farther from tower

Bandwidth / Channel Width

LTE: 1.4, 3, 5, 10, 15, 20 MHz
NR: Up to 100 MHz (sub-6 GHz), 400 MHz (mmWave)
Wider = more capacity

CQI (Channel Quality Indicator)

LTE downlink quality metric
0-15 (higher is better)
Used for adaptive modulation

Band

Frequency range
The app’s band reference lists LTE bands 1 to 111 and NR bands n1 to n263 (not every number in between is assigned)
Example: Band 12 = 700 MHz, n71 = 600 MHz

Cell states

In Service

Connected to network
Can make/receive calls and data

Out of Service

No network connection
No cell towers available

Emergency Calls Only

Can see network but not registered
SIM issue or roaming restriction

Camped

Registered to cell in idle mode
Not actively transmitting
Ready to receive

Connected

Active data/call session
Transmitting and receiving

Handover / handoff

Handover

Transition between cells
Maintains connection during movement
Can be inter-sector or inter-tower

Intra-frequency Handover

Between cells on same frequency
Faster handover

Inter-frequency Handover

Between different frequencies
Requires measurement gaps

Inter-RAT Handover

Between different technologies (e.g., LTE → NR)
More complex

Advanced terms

DOP (Dilution of Precision)

GPS accuracy factor (not cellular, but in GNSS)
HDOP: Horizontal
VDOP: Vertical
PDOP: Position
Lower = better geometry

Carrier Aggregation

LTE/NR combining multiple carriers
Increases data speed
The Cellular view shows it as “Carrier aggregation · 3 carriers · 210 MHz” with one chip per carrier

Branding (override network type)

The label a carrier asks the phone to show in the status bar, which can differ from the real technology
Shown on the Cellular view’s Branding pill as LTE-CA, LTE Adv Pro, NR NSA, NR NSA mmWave, NR Advanced, or None

MIMO (Multiple Input Multiple Output)

Multiple antennas for faster speeds
2×2, 4×4, massive MIMO
Common in LTE/NR

RRC (Radio Resource Control)

Protocol managing connection states
IDLE vs CONNECTED
Controls handovers, measurements

NSA (Non-Standalone) 5G

5G NR using LTE core network
Early 5G deployment
Requires LTE anchor

SA (Standalone) 5G

5G NR with 5G core
True 5G architecture
No LTE dependency

Cellular networks: the Cellular view and its fields
Cellular tools: band reference and eNB, gNB, and PCI calculators