📖 Reference Glossary
Over 80 technical terms, acronyms and definitions covering the complete LTE450 ecosystem. Use Ctrl+F to search, or browse alphabetically using the navigation below.
A
- AES (Advanced Encryption Standard)
- Symmetric block cipher used for air interface encryption in LTE networks (EEA2 algorithm). AES-128 is the standard key length used in LTE security, considered unbreakable with current computing technology.
- AKA (Authentication and Key Agreement)
- The 3GPP mutual authentication protocol used in LTE networks. The device authenticates to the network (and vice versa) using a challenge-response mechanism based on the secret key (Ki) stored in the SIM and in the HSS.
- AMI (Automated Meter Infrastructure)
- The complete system for two-way communication between smart utility meters and the head-end system. AMI includes the smart meters, the communication network (which may include LTE450 for wide-area backhaul), data collection units, and the meter data management system (MDMS).
- APN (Access Point Name)
- The network identifier used by a mobile device to establish a data connection through the P-GW to an external network. A private APN routes traffic to a utility’s own network rather than to the public internet, providing traffic isolation and security.
- ARP (Allocation and Retention Priority)
- A QoS parameter in LTE that determines which EPS Bearers are retained during network congestion and pre-emption events. Bearers with higher ARP priority (lower number) pre-empt lower priority bearers during congestion.
B
- Band 31
- 3GPP LTE operating band using 452.5-457.5 MHz uplink and 462.5-467.5 MHz downlink, with 10 MHz FDD duplex spacing and 5 MHz channel bandwidth. The primary LTE450 band in Germany and continental Europe.
- Band 72
- 3GPP LTE operating band using 461-469 MHz uplink and 451-459 MHz downlink, with 10 MHz FDD duplex spacing and 5 MHz channel bandwidth. Used in Finland and some Nordic LTE450 deployments.
- Band 87/88
- 3GPP LTE operating bands in the lower 410-425 MHz range. Band 87: 410-415 MHz UL / 420-425 MHz DL. Band 88: 412-417 MHz UL / 422-427 MHz DL. Less commonly deployed than Band 31/72.
- BBU (Baseband Unit)
- The base station component that performs digital signal processing, protocol stack execution, and backhaul connectivity. Typically located in a cabinet at the base of a mast or in a nearby equipment room, connected to the Remote Radio Unit (RRU) via optical fibre.
C
- CEPT (European Conference of Postal and Telecommunications Administrations)
- The European organisation that coordinates telecommunications and postal regulation across 48 member countries. CEPT’s Electronic Communications Committee (ECC) publishes decisions and recommendations on spectrum harmonisation, including ECC Decision (09)03 for LTE450.
- CE (European Conformity)
- The CE marking required on radio equipment placed on the EU market, demonstrating compliance with the Radio Equipment Directive (RED). LTE450 devices sold in EU markets require CE marking, supported by a Declaration of Conformity against relevant ETSI harmonised standards.
- CPE (Customer Premises Equipment)
- A self-contained cellular device installed at the customer’s site. For LTE450, outdoor CPE units combine the cellular modem, antenna, and weatherproof enclosure in a single unit mounted on a wall, pole or substation fence.
D
- DCU (Data Collection Unit)
- Also called a concentrator. In AMI networks, a DCU aggregates meter data from a cluster of smart meters (typically via Wireless M-Bus or PLC) and transmits the collected data to the head-end system via a wide-area backhaul connection such as LTE450.
- DERMS (Distributed Energy Resource Management System)
- Software platform used by electricity DSOs to monitor and control distributed energy resources (solar PV, battery storage, EV chargers, flexible loads) connected to the distribution network. Requires real-time communication with thousands of dispersed assets, typically over LTE450 or similar utility connectivity.
- DNP3 (Distributed Network Protocol 3)
- A set of communications protocols used in SCADA systems, particularly in North American utilities. DNP3 over TCP/IP operates transparently over LTE450 cellular connections.
- DSO (Distribution System Operator)
- The company responsible for operating the electricity distribution network (below 132kV in the UK) within a defined geographic area. DSOs are the primary customer for LTE450 utility connectivity in the electricity sector.
E
- EARFCN (E-UTRA Absolute Radio Frequency Channel Number)
- The unique number identifying a specific LTE carrier frequency. Each EARFCN maps to a specific uplink or downlink frequency within a given LTE band. For Band 31 downlink, EARFCNs run from 9770 (462.5 MHz) to 9869 (467.475 MHz).
- ECC (Electronic Communications Committee)
- The committee of CEPT responsible for spectrum management, numbering, and regulatory decisions for electronic communications in Europe. Published ECC Decision (09)03 harmonising 450-470 MHz for LTE use.
- eDRX (Extended Discontinuous Reception)
- An LTE power saving feature (3GPP Release 13) that extends the device’s paging reception cycle from a few seconds to up to 44 minutes, allowing IoT devices to sleep for extended periods between checking for downlink data. Used in LTE450 IoT deployments for battery-powered devices.
- EIRP (Equivalent Isotropically Radiated Power)
- The total power radiated by an antenna in its direction of maximum gain, relative to an isotropic radiator. EIRP = Transmit Power + Antenna Gain – Cable Loss. Spectrum licences typically specify a maximum EIRP to control interference.
- eNodeB / eNB (evolved Node B)
- The base station in an LTE network. Each eNodeB manages one or more radio cells, controlling transmission and reception, scheduling resource allocation, and communicating with the EPC via the S1 interface. In LTE450, eNodeBs are typically macro base stations serving large geographic areas.
- EPC (Evolved Packet Core)
- The core network of an LTE system, comprising the MME, S-GW, P-GW, and HSS. The EPC handles authentication, QoS, routing, and connectivity to external networks. In private LTE450 networks, the EPC is deployed by the network operator rather than a public MNO.
- eUICC (embedded Universal Integrated Circuit Card)
- Also known as eSIM. A SIM chip that can store multiple network operator profiles and switch between them remotely using the GSMA RSP (Remote SIM Provisioning) protocols. eUICC enables remote SIM management for large LTE450 device fleets. See euicc.co.uk for full technical reference.
F
- FDD (Frequency Division Duplex)
- Duplex mode where uplink and downlink transmissions occur simultaneously on different frequencies. LTE450 universally uses FDD, with separate uplink and downlink frequency bands separated by a duplex gap (typically 10 MHz for Band 31 and Band 72).
- FLISR (Fault Location, Isolation, and Service Restoration)
- Automated grid management function that detects, locates, and isolates faults on the electricity distribution network and restores supply to unaffected customers within seconds or minutes. FLISR relies on real-time communications (typically LTE450) with automated switchgear and sensors across the network.
- FSPL (Free-Space Path Loss)
- The attenuation of radio wave power between a transmitter and receiver in free space (no obstacles). FSPL increases with both distance and frequency. At 450 MHz, FSPL is approximately 6 dB less than at 900 MHz and 12 dB less than at 1800 MHz for the same distance, explaining LTE450’s superior range.
G
- GBR (Guaranteed Bit Rate)
- An LTE QoS class that guarantees a minimum data rate for a bearer regardless of network load. Used for latency-sensitive applications such as VoLTE and mission-critical SCADA communications on LTE450 networks.
- GCF (Global Certification Forum)
- Industry body coordinating device conformance testing against 3GPP specifications. GCF certification indicates that a device has passed standardised conformance tests and is likely to operate correctly on any compliant LTE network.
- GOOSE (Generic Object-Oriented Substation Event)
- High-speed multicast messaging defined in IEC 61850-8-1, used for protection and control signalling between IEDs in substations. GOOSE messages require end-to-end delivery within 4-20 ms depending on protection class. LTE450 can support Class P2/P3 GOOSE (20 ms) with appropriate QoS configuration.
- GSMA
- The global mobile industry association representing mobile network operators worldwide. The GSMA publishes the eSIM/RSP specifications (SGP.01, SGP.02, SGP.22, SGP.32) and the IoT Device Connection Efficiency Guidelines relevant to LTE450 IoT deployments.
H
- HARQ (Hybrid Automatic Repeat Request)
- LTE error correction mechanism combining forward error correction (FEC) with automatic repeat request (ARQ). HARQ retransmissions are managed at the MAC layer with fast feedback, minimising retransmission delay. Each HARQ round trip adds approximately 8 ms to latency.
- HSS (Home Subscriber Server)
- The central database in an LTE EPC that stores subscriber profiles, authentication keys (Ki), and service subscriptions. In a private LTE450 network, the HSS is operated by the network owner and contains records only for their own authorised devices.
L
- LTE (Long-Term Evolution)
- The 4G mobile broadband standard developed by 3GPP. All-IP, packet-switched technology using OFDMA downlink and SC-FDMA uplink. Defined in 3GPP Release 8 (December 2008) with enhancements in Releases 9-18. LTE450 is standard LTE applied to the 450 MHz frequency band.
- LTE-M (LTE for Machines)
- Also known as eMTC or Cat-M1. A 3GPP Release 13 LTE enhancement for IoT, providing reduced bandwidth (1.4 MHz per device), extended coverage (+15 dB vs standard LTE), and power saving modes (PSM, eDRX) for long battery life. LTE-M can operate at 450 MHz on LTE450 networks where chipset support is available.
- Link Budget
- The calculation of signal power gains and losses between transmitter and receiver, determining the maximum allowable path loss (MAPL) and hence the maximum cell radius. A higher MAPL means greater range. LTE450’s advantage is a higher MAPL than higher-frequency LTE bands due to lower free-space path loss at 450 MHz.
M
- MAPL (Maximum Allowable Path Loss)
- The maximum permitted path loss between transmitter and receiver in a link budget calculation, above which the link fails. Determined by EIRP, receiver sensitivity, and various margins. A higher MAPL corresponds to greater coverage range.
- MDMS (Meter Data Management System)
- The head-end software system that receives, processes, validates and stores meter data from AMI networks. The MDMS connects to the wide-area network (which may use LTE450 backhaul) and to billing, asset management and distribution management systems.
- MFF2 (Machine Form Factor 2)
- A soldered SIM chip form factor defined in ETSI TS 102 671. MFF2 SIMs are bonded to the PCB during manufacture, providing resistance to vibration, shock, temperature extremes, and physical tampering. Recommended for utility field equipment on LTE450 networks.
- MIMO (Multiple Input, Multiple Output)
- Antenna technology using multiple transmit and receive antennas to increase throughput and/or reliability. LTE450 typically uses 2×2 MIMO (two transmit, two receive antennas), approximately doubling peak throughput compared to SISO. MIMO antenna dimensions at 450 MHz are larger than at higher frequencies.
- MME (Mobility Management Entity)
- The EPC component responsible for device authentication, session management, mobility (handover), and paging. The MME connects to the eNodeB via the S1-MME interface and to the HSS via the S6a interface.
- MNO (Mobile Network Operator)
- A company that owns and operates a mobile network. Distinguished from an MVNO (Mobile Virtual Network Operator), which resells capacity on an MNO’s network. LTE450 utility networks are typically built by specialist operators rather than traditional MNOs.
N
- NB-IoT (Narrowband IoT)
- A 3GPP Release 13 radio access technology for IoT, using a 180 kHz channel width and providing very long battery life but low throughput (20-250 kbps). Less common than LTE-M at 450 MHz but technically feasible in the band.
- NIS Regulations
- The Network and Information Systems Regulations 2018, implementing the EU NIS Directive in the UK. Applies to operators of essential services (including energy utilities) and requires appropriate cybersecurity measures and incident reporting.
- NR (New Radio)
- The 5G radio access standard defined by 3GPP from Release 15 onwards. NR bands at 450 MHz (n31, n72) provide a migration path from LTE450 to 5G on the same spectrum.
O
- OFDMA (Orthogonal Frequency Division Multiple Access)
- The multiple access scheme used in LTE downlink. The channel is divided into many orthogonal subcarriers (each 15 kHz wide) that can be allocated flexibly to different users per scheduling interval.
- OT (Operational Technology)
- The hardware and software that controls and monitors physical devices, processes, and infrastructure. Electricity substation equipment, SCADA systems, and smart meters are OT. OT networks connected via LTE450 must be isolated from IT networks to prevent cyber threats propagating to critical control systems.
P
- P-GW (Packet Data Network Gateway)
- The EPC component that connects the LTE network to external IP networks. For a private LTE450 network, the P-GW enforces the private APN and routes utility device traffic to the utility’s own network.
- PSM (Power Saving Mode)
- An LTE feature (3GPP Release 12) that allows IoT devices to switch off their radio for extended periods (hours to days) and only wake for scheduled transmissions. PSM extends battery life to years for infrequent-reporting IoT applications on LTE450 networks.
Q
- QCI (QoS Class Identifier)
- A number (1-9 for standardised classes, plus operator-specific values) assigned to an LTE EPS Bearer that defines its priority, packet delay budget, and error rate target. QCI 1 is the highest priority (GBR, 100 ms delay budget, for conversational voice). Critical SCADA and protection traffic on LTE450 is assigned high QCI values.
- QoS (Quality of Service)
- The set of policies and mechanisms that prioritise network traffic and guarantee performance parameters (latency, jitter, throughput) for specific applications. Private LTE450 networks provide full QoS control, a key advantage over public mobile MVNO arrangements.
R
- RED (Radio Equipment Directive)
- EU Directive 2014/53/EU requiring radio equipment placed on the EU market to meet essential requirements on health, safety, electromagnetic compatibility, and spectrum use. LTE450 devices must comply with RED and carry CE marking.
- Resource Block (RB)
- The minimum unit of LTE radio resource allocation, comprising 12 subcarriers (180 kHz) over one 0.5 ms slot. A 5 MHz LTE channel provides 25 resource blocks. The scheduler allocates resource blocks to devices on a per-subframe (1 ms) basis.
- RSRP (Reference Signal Received Power)
- The average power of the LTE reference signals received by a device, measured in dBm. The primary measure of LTE signal strength. Target RSRP for reliable LTE450 utility connectivity is typically greater than -110 dBm.
- RSRQ (Reference Signal Received Quality)
- A measure of LTE signal quality combining RSRP with received noise and interference. Measured in dB. RSRQ greater than -12 dB is generally required for reliable connectivity.
- RTU (Remote Terminal Unit)
- A field device in a SCADA system that collects sensor data (voltage, current, status) and transmits it to the master station, and receives and executes control commands. RTUs in electricity substations are primary endpoints for LTE450 SCADA connectivity.
- RRU/RRH (Remote Radio Unit / Remote Radio Head)
- The active antenna-mounted component of a split base station architecture that performs RF processing (digital-to-analogue conversion, power amplification, filtering) close to the antenna, minimising feeder cable losses. Connected to the BBU via optical fibre.
S
- SC-FDMA (Single Carrier Frequency Division Multiple Access)
- The multiple access scheme used in LTE uplink (device to base station). SC-FDMA provides lower peak-to-average power ratio than OFDMA, benefiting battery-powered devices and simplifying power amplifier design.
- SCADA (Supervisory Control and Data Acquisition)
- Systems for real-time remote monitoring and control of industrial plant and infrastructure. Electricity utility SCADA over LTE450 typically uses IEC 60870-5-104 or DNP3 over TCP/IP.
- SGP.32
- GSMA specification for IoT eSIM remote SIM provisioning. Designed for resource-constrained devices that may be intermittently connected – directly applicable to smart meters and remote sensors on LTE450 networks. Full technical reference at euicc.co.uk.
- SINR (Signal-to-Interference-plus-Noise Ratio)
- A measure of signal quality relative to both noise and interference. SINR greater than 0 dB is generally required for connectivity; higher SINR enables higher modulation schemes (64QAM, 256QAM) and higher throughput.
T
- TS 36.101
- 3GPP Technical Specification defining User Equipment (device) RF performance requirements for LTE, including per-band frequency ranges, transmit power limits, and receiver sensitivity requirements. The primary specification for LTE450 device RF requirements.
- TS 36.104
- 3GPP Technical Specification defining Base Station (eNodeB) RF performance requirements for LTE.
U
- UE (User Equipment)
- 3GPP term for the device connecting to an LTE network. In LTE450 utility networks, UEs include industrial routers, M2M modules, smart meters, and IoT sensors rather than consumer smartphones.
- UKCA (UK Conformity Assessed)
- The UK marking requirement for products placed on the UK market following Brexit, equivalent to CE marking for EU markets. LTE450 devices sold in the UK require UKCA marking from 2024.
V
- VoLTE (Voice over LTE)
- LTE-based voice call technology using the IMS (IP Multimedia Subsystem) core network. Provides higher voice quality than 2G/3G voice. LTE450 networks can support VoLTE for field worker communications if the EPC includes an IMS.
- VSWR (Voltage Standing Wave Ratio)
- A measure of impedance mismatch between an antenna and its feed cable. VSWR of 1:1 is perfect matching; 2:1 means approximately 11% power reflection. LTE450 antennas should achieve VSWR better than 1.5:1 across the operating band.
W
- WRC (World Radiocommunication Conference)
- ITU conferences held every 3-4 years that review and revise the Radio Regulations governing spectrum use globally. WRC-07 added the IMT identification for the 450-470 MHz band, enabling LTE450 deployments worldwide.