| 2 |
| 2G | Second Generation GSM / EDGE |
| 3 |
| 3G | Third Generation UMTS / HS / HS+ |
| 3GPP | 3rd Generation Partnership Project (www.3gpp.org) |
| 4 |
| 4G | Fourth Generation LTE |
| 5 |
| 5G | Fifth Generation NR |
| 5G-AN | 5G Access Network |
| 5G-EIR | 5G-Equipment Identity Register |
| 5G-GUTI | 5G Globally Unique Temporary Identifier |
| 5G-S-TMSI | 5G S-Temporary Mobile Subscription Identifier |
| 5GC | 5G Core Network (24.301) |
| 5GS | 5G System |
| 5QI | 5G QoS Indicator |
| A |
| A-CSI | Aperiodic CSI |
| A-MPR | Additional maximum power reduction |
| AAS | Active Antenna System |
| ACB | Access Class Barring |
| ACK | Acknowledgment |
| ACLR | Adjacent Channel Leakage Ratio |
| AES | Advanced Encryption Standard |
| AI | Air-interface |
| AKA | Authentication and Key Agreement |
| AM | Acknowledged Mode |
| AMBR | Aggregate Maximum Bit Rate |
| AMC | Adaptive Modulation and Coding |
| AMF | Access and Mobility Management Function |
| ANR | Automatic Neighbour Relation |
| AoA | Angle of Arrival |
| AP | Antenna port |
| ARFCN | Absolute radio-frequency channel number |
| ARP | Allocation and Retention Priority |
| ASN.1 | Abstract Syntax Notation One |
| AUSF | Authentication Server Function (NR) |
| AWGN | Additive White Gaussian Noise |
| B |
| BCH | Broadcast Channel |
| BD | Blind detection |
| BFD | Beam Failure Detection |
| BFR | Beam Failure Recovery |
| BI | Backoff Indicator (38.321) |
| BLER | Block Error Rate |
| BPL | Beam Pair Link |
| BPSK | Binary Phase Shift Keying |
| BRRS | Beam Refinement Reference Signal |
| BRS | Beam Reference Signal |
| BS | Base Station |
| BSI | Beam state information |
| BSR | buffer status report |
| BW | Bandwidth |
| BWP | Bandwidth part |
| C |
| C-RNTI | Cell RNTI |
| CA | Carrier Aggregation |
| CBG | Code Block Group |
| CBRA | Contention Based Random Access |
| CBSR | Code Book Subset Restriction |
| CBW | Channel band width |
| CC | Component carrier |
| CC | Convolutional Code |
| CCA | Clear Channel Assessment |
| CCE | Control channel element |
| CCO | Cell Change Order |
| CDM | Code division multiplexing |
| CE | Channel Estimation |
| CFRA | Contention Free Random Access |
| CFRA | Contention Free Random Access |
| CGI | Cell Global ID |
| CHO | Conditional Handover |
| CIR | Channel Impulse Response |
| CJT | Coherent Joint Transmission |
| CK | Cipher Key |
| CLI | Cross Link Interference |
| CMAS | Commercial Mobile Alert Service |
| CMR | Codec Mode Request |
| CoMP | Coordinated multi point (tranmission) |
| CORESET | Control Resource Set |
| COT | Channel Occupancy Time |
| CP | Control Plane |
| CP | Cyclic prefix |
| CPE | Common phase error |
| CPE | Customer Premise Equipment |
| CPRI | Common Public Radio Interface |
| CQI | Channel Quality Indicator |
| CRB | Common resource block |
| CRC | Cyclic redundancy check |
| CRI | CSI-RS resource indicator |
| CRS | Cell-specific Reference Signal |
| CS-RNTI | Configured Scheduling RNTI (38.321) |
| CSI | Channel state information |
| CSI-IM | CSI Interference Measurement |
| CSI-RS | Channel state information reference signal |
| CSMA/CA | Channel Sense Multiple Access with Collision Avoidance |
| CSS | Common search space |
| CTS | Cleat-To-Send |
| CW | Codeword |
| CWS | Contention Window Size |
| D |
| D2D | Device to device |
| DAI | Downlink Assignment Index |
| DAS | Distributed Antenna System |
| DC | Dual Connectivity (3x.101) |
| DCI | Downlink control information (PDCCH) |
| DFS | Dynamic Frequency Selection |
| DFT-s-OFDM | Discrete Fourier Transfom spread Orthogonal Frequency Division Multiplexing |
| DL | Downlink |
| DM-RS | Demodulation reference signal |
| DRB | (user) Data Radio Bearer |
| DRS | Discovery Reference Signal |
| DRX | Discontinuous Reception |
| DSAC | Domain Specific ACB |
| DSS | Dynamic Spectrum Sharing |
| DTX | Discontinuous Transmission |
| DUT | Device Under Test |
| DwPTS | Downlink Pilot Time Slot |
| E |
| E-UTRAN | Evolved Universal Terrestrial Access Network |
| EAB | Extended Access Barring |
| EAP | Extensible Authentication Protocol |
| EBB | Eigen based beamforming |
| EBF | Elevation Beam Forming |
| ED | Energy Detection |
| EIRP | Equivalent Isotropic Radiated Power |
| eLAA | Enhanced License Assisted Access |
| eMBB | Enhanced Mobile Broadband |
| EN-DC | E-UTRA - NR Dual Connectivity (37.340) |
| eNB | E-UTRAN NodeB |
| EPC | Evolved Packet Core |
| ePDG | Evolved Packet Data Gateway |
| EPRE | Energy per resource element |
| EPS | Evolved Packet System |
| ETSI | European Telecommunications Standards Institute |
| ETWS | Earthquake and Tsunami Warning System |
| EVM | Error Vector Magnitude |
| F |
| FBE | Frame Based Equipment |
| FBW | Fractional Bandwidth |
| FDD | Frequency Division Duplex |
| FDRA | Frequency domain resource assignment |
| FeLAA | Further Enhanced LAA |
| FL | Front-Loaded (DMRS) |
| FOC | Frequency offset correction |
| FOE | Frequency offset estimation |
| FPGA | Field-Programmable Gate Array |
| FR | Frequency Range |
| FR1 | Frequency range 410 MHz - 7125 MHz |
| FR2 | Frequency range 24.25 GHz – 52.6 GHz |
| FRC | Fixed Reference Channel |
| FTP | File Transfer Protocol |
| FWA | Fixed Wireless Access |
| G |
| gNB | next Generation Node B |
| gNB-CU | gNB Central Unit (RRC, SDAP and PDCP) |
| gNB-DU | gNB Distributed Unit (RLC, MAC and PHY layers) |
| GNSS | Global Navigation Satellite System |
| GoB | Grid of beams |
| GSCN | Global Synchronization Channel Number |
| GTP | GPRS Tunneling Protocol (29.060) |
| GUAMI | Globally Unique AMF Identifier (38.413) |
| GUMMEI | Globally Unique MME Identifier |
| GUTI | Globally Unique Temporary UE Identity (23.003) |
| H |
| HAPS | High Altitude Platform Station |
| HARQ | Hybrid Automatic Repeat Request |
| HFN | Hyper Frame Number |
| HLR | Home Location Register |
| HO | Hand Over |
| HRL | Handover Restriction List |
| HSS | Home Subscriber Server |
| I |
| IAB | Integrated Access and Backhaul |
| IBB | In-band Blocking |
| ICI | Intercarrier interference |
| IDFT | Inverse Discrete Fourier Transformation |
| IE | Information Element |
| IK | Integrity Key |
| ILLA | Inner Loop Link Adaptation |
| IM | Interference Management |
| IMEI | International Mobile Equipment Identity (23.003) |
| IMR | Interference measurement resource |
| IMS | IP Multimedia Subsystem |
| IMSI | International Mobile Subscriber Identity (31.102) |
| IMT | International Mobile Communication |
| INT-RNTI | Interruption RNTI (38.321) |
| IoT | Internet of Things |
| IQ | In-phase and Quadrature |
| IRAT | Inter-Radio Access Technology |
| IRC | Interference Rejection Combining (Receiver) |
| ISC | Unified Access Control |
| ISD | Inter-sites distance |
| ITU R | Radiocommunication Sector of the International Telecommunication Union |
| J |
| JT CoMP | Joint transmission coordinated multipoint |
| K |
| KDF | Key Derivation Function |
| L |
| LAA | License Assisted Access |
| LADN | Local Area Data Network |
| LBE | Load Based Equipment |
| LBRM | limited buffer rate matching |
| LBT | Listen Before Talk |
| LCID | Logical Channel ID (38.321) |
| LDPC | Low Density Parity Check |
| LI | Layer indicator |
| LMDS | Local Multipoint Distribution Service |
| LRR | Long Range Radar |
| LRR | Link Recovery Request |
| LTE | Long Term Evolution |
| LWA | LTE-WLAN Aggregation |
| LWIP | LTE WLAN integration with IPSec tunnel |
| M |
| MAC | Medium Access Control (3x.321) |
| MAC-I | Message Authentication Code for Integrity |
| MBMS | Multimedia Broadcast Multicast Services |
| MBSFN | Multicast Broadcast Single Frequency Network |
| MCG | Master cell group |
| MCL | Maximum Coupling Loss |
| MCOT | Maximum Channel Occupancy Time |
| MCS | Mission Critical Service |
| MCS | Modulation and coding scheme |
| MEC | Multi-access Edge Computing |
| MeNB | Master eNB |
| MFBI | Multiple Frequency Band Indicator |
| MIB | Master Information Block |
| MICO | Mobile Initiated Connection only (no listen to Paging) |
| MIMO | Multiple Input Multiple Output |
| MME | Mobility Management Entity |
| MMSE | Minimum mean square error (Receiver) |
| mMTC | Massive Machine Type Communications |
| MMTel | Multimedia telephony service |
| MN | Master Node |
| MNC | Mobile Network Code |
| MO | Mobile Originated |
| MOP | Maximum Output Power |
| MPC | Multimedia Priority Service |
| MPE | Maximum Permissible Exposure |
| MR-DC | Multi-RAT Dual Connectivity |
| MRC | Maximum Radio Combining |
| MSI | Minimum System Information |
| MT | Mobile Terminated |
| MTC | Machine Type Communication |
| MU-MIMO | Multi User MIMO |
| N |
| NACK | Negative Acknowledgment |
| NAS | Non Access Stratum (24.301) |
| NCGI | NR Cell Global Identifier |
| NCJT | Non-Coherent Joint Transmission |
| NCRs | Neighbour Cell Relations |
| NOMA | Non-Orthogonal Multiple Access |
| NR | New Radio Access |
| NRF | Network Repository Function |
| NSA | Non Standalone |
| NSSAI | Network Slice Selection Assistance Information |
| NSSF | Network Slice Selection Function (NR) |
| NTN | Non-terrestrial networks |
| NZP CSI-RS | Non-zero power CSI Reference Signal |
| O |
| O&M | Operation and Maintenance |
| OAM | Operations, Administration and Maintenance |
| OCB | Occupied Channel Bandwidth |
| OCC | Orthogonal cover code |
| OCNS | Orthogonal Channel Noise Simulator |
| OEM | Original Equipment Manufacturer |
| OFDM | Orthogonal Frequency Division Multiplex(ing) |
| OLLA | Outer Loop Link Adaptation |
| OOB | Out-of-band |
| OSI | Other System Information |
| OTA | Over The Air |
| OTDOA | Observed Time Difference Of Arrival |
| P |
| PAPR | Peak to Average Power Ratio |
| PBCH | Physical Broadcast CHannel |
| PBR | Prioritised bit rate |
| PCCH | Paging Control Channel |
| PCell | Primary Cell |
| PCF | Policy Control Function (NR) |
| PCH | Paging Channel |
| PCI | Physical Cell Identity (36.331) |
| PCO | Protocol Configuration Options |
| PCRF | Policy and Charging Rules Function |
| PDCCH | Physical downlink control channel |
| PDCP | Packet Data Convergence Protocol (3x.323) |
| PDN | Packet Data Network |
| PDSCH | Physical downlink shared channel |
| PDU | Protocol Data Unit |
| PHR | Power Headroom Report |
| PLMN | Public Land Mobile Network |
| PMI | Precoding Matrix Indicator |
| PO | Paging Occasion |
| PPAC | Paging Permission with Access Control |
| PPDR | Public Protection and Disaster Relief |
| PRACH | Physical random access channel |
| PRB | Physical Resource Block |
| ProSe | Proximity-based Services |
| PRS | Positioning Reference Signal |
| PSA | PDU session anchor |
| PSD | Power Spectral Density |
| PSS | Primary Synchronisation Signal |
| PT-RS | Phase tracking reference signal |
| PTI | Precoding Type Indicator |
| PUCCH | Physical uplink control channel |
| PUSCH | Physical uplink shared channel |
| PWS | Public Warning System |
| Q |
| QAM | Quadrature Amplitude Modulation |
| QCL | Quasi Co-Location |
| QFI | QoS Flow Identity |
| QoS | Quality of Service |
| QPSK | Quadrature Phase Shift Keying |
| R |
| RACH | Random Access Channel |
| RAPID | Random Access Preamble ID (38.321) |
| RAR | Random Access Response |
| RAT | Radio Access Technology |
| RAU | Routing Area Update |
| RB | Resource Block |
| RBG | Resource Block Group |
| RDI | Reflective QoS flow to DRB mapping Indication |
| RE | Resource Element |
| RedCap | Reduced Capability |
| REFSENS | Reference Sensitivity |
| REGs | Resource element groups |
| RF | Radio Frequency |
| RFSP | RAT Frequency Selection Policy |
| RI | Rank Indicator |
| RIC | RAN Intelligent Controller |
| RIV | Resource indicator value |
| RLC | Radio Link Control (3x.322) |
| RLF | Radio Link Failure |
| RLM | Radio Link Monitoring |
| RMC | Reference Measurement Channel |
| RMR | Railway Mobile Radio |
| RMS | Root Mean Square (value) |
| RMSI | Remaining Minimum SI (SystemInformationBlockType1) |
| RNAU | Ran Notification Area Update |
| RNTI | Radio Network Temporary Identifier |
| ROHC | RObust Header Compression |
| RQA | Reflective QoS Attribute |
| RQI | Reflective QoS Indication |
| RRC | Radio Resource Control (3x.331) |
| RRM | Radio Resource Management |
| RSRP | Reference signal received power |
| RSRQ | Reference Signal Received Quality |
| RSSI | Received signal strength indicator |
| RSTD | Reference signal time difference |
| RTS | Ready-To-Send |
| RTT | Round Trip Time |
| RTWP | Received Total Wideband Power |
| RV | Redundancy Version |
| S |
| S1 | Interface between E-UTRAN and the EPC (36.413) |
| SA | Stand alone |
| SAR | Segmentation and Reassembly |
| SAR | Specific Absorption Rate |
| SCC | Secondary Component Carrier |
| SCell | Secondary Cell |
| SCG | Secondary cell group |
| SCS | Sub-Carrier Spacing |
| SCTP | Stream Control Transmission Protocol |
| SD | Slice Differentiator |
| SDAP | Service Data Adaptation Protocol |
| SDL | Supplementary Downlink |
| SDU | Service Data Unit |
| SEAF | SEcurity Anchor Function |
| SEM | Spectrum Emission Mask |
| SFBC | Space Frequency Block Code |
| SFI | Slot format indication |
| SFI-RNTI | Slot Format Indication RNTI (38.321) |
| SFN | System Frame Number |
| SFTD | SFN and frame timing difference |
| SgNB | Secondary gNb |
| SI-RNTI | System Information RNTI |
| SIB | System Information Block |
| SINR | Signal to Interference and Noise Ratio |
| SIPTO | Selected IP Traffic Offload |
| SISO | Single Input Single Output |
| SLIV | Start and length indicator value |
| SMF | Session Management Function |
| SMO | Service Management and Orchestration |
| SMTC | SS/PBCH Block Measurement Time Configuration |
| SN | Sequence Number |
| SN | Secondary Node |
| SNR | Signal-to-Noise Ratio |
| SON | Self-Organizing Networks |
| SP-CSI-RNTI | Semi-Persistent CSI RNTI (38.321) |
| SPID | Service Profile Identifier |
| SPS | Semi-Persistent Scheduling |
| SQN | Sequence Number |
| SR | Scheduling Request |
| SRB | Signalling Radio Bearer carrying control plane data |
| SRI | Scheduling request indicator |
| SRI | SRS resource indicator |
| SRI | Satellite Radio Interface |
| SRR | Short Range Radar |
| SRS | Sounding Reference Signal (UL) |
| SRVCC | Single Radio Voice Call Continuity |
| SSAC | Service Specific Access Control |
| SSB | Synchronization Signal Block |
| SSC | Session and Service Continuity |
| SSS | Secondary Synchronization Signal |
| SU-MIMO | Single User MIMO |
| SUCI | Subscription Concealed Identifier |
| SUL | Supplementary Uplink |
| SUPI | Subscription Permanent Identifier |
| T |
| TAC | Tracking Area Code |
| TAE | Time Alignment Error |
| TAG | Timing advance group |
| TAU | Tracking Area Update |
| TB | Transport Block |
| TBS | Transport Block Size |
| TCI | Transmission configuration indication |
| TDD | Time Division Duplex |
| TDM | Time division multiplexing |
| TDRA | Time Domain Resource Allocation |
| TEID | Tunnel Endpoint Identifier |
| TMSI | Temporary Mobile Subscriber Identity |
| TNL | Transport Network Layer |
| TNLA | Transport Network Layer Association |
| TOC | Time offset correction |
| TOE | Time offset estimation |
| TPC | Transmitter Power Control |
| TPC-CS-RNTI | Transmit Power Control-Configured Scheduling-RNTI (38.321) |
| TPC-SRS-RNTI | Transmit Power Control-Sounding Reference Symbols-RNTI (38.321) |
| TPMI | Transmitted Precoding Matrix Indicator |
| TPMI | Transmit Precoding Matrix Indicator |
| TRI | Transmit Rank Indicator |
| TRP | Transmit-Receive Point |
| TRP | Total Received Power |
| TRP | Total Radiated Power |
| TRS | Tracking Reference Signal (CSI-RS) |
| TTI | Transmission Time Interval |
| TxDiv | Transmit diversity |
| U |
| UAS | Unmanned Aircraft System (38.821) |
| UCI | Uplink Control Information (PUCCH) |
| UDM | Unified Data Management (HSS) |
| UE | User Equipment |
| UEM | Unwanted Emissions Mask |
| UL | Uplink |
| UL-SCH | Uplink Shared Channel |
| UM | Unacknowledged Mode |
| UP | User Plane |
| UPF | User Plane Function |
| UPT | User Perceived Throughput |
| uRLLC | Ultra-reliable low latency communication |
| URSP | UE Route Selection Policy |
| USIM | Universal Subscriber Identity Module |
| USS | UE specific search space |
| UTRA | Universal Terrestrial Access Network |
| UwPTS | Uplink Pilot Time Slot |
| V |
| V2X | Vehicle to Everything |
| VLR | Visitor Location Register |
| VoIP | Voice-Over-Internet-Protocol |
| VRB | Virtual resource block |
| W |
| WA | Wide Area |
| WLAN | Wireless Local Area Network |
| X |
| X2AP | X2 Application Protocol (36.423) |
| Z |
| ZC | Zadoff-Chu |
| ZF | Zero Forcing |
