This topic presents in a very simplified way all the main concepts that should be understood by those who know 5G NR.
5G NR UE Measurements
5G NR UE Measurements are measurements used by devices to evaluate the network’s signal strength, quality, and performance, ensuring reliable connections and efficient mobility. Measurements like SS-RSRP and SS-RSRQ assess signal power and quality, helping devices select the best cell and manage movement between cells, while SS-SINR focuses on signal clarity by comparing it to interference and noise. Advanced measurements like CSI-RSRP, CSI-RSRQ, and CSI-SINR provide similar insights but are specifically tailored for managing directional beams and high-speed mobility, essential in 5G’s beam-based architecture. Additional capabilities, such as SFN and Frame Timing Difference (SFTD), synchronize 4G and 5G networks for seamless operation in mixed environments, and other measurements, like those for positioning (GNSS, OTDOA, and WLAN), support precise location tracking. Together, these measurements enable 5G to deliver faster, more reliable, and smarter connectivity than previous networks. [In a Nutshell: 5G UE Measurements assess signal strength, quality, and performance, ensuring smooth mobility, beam management, synchronization, and accurate positioning.]
Imagine LTE and 5G as two cities: LTE City is good and reliable, with streetlights (RSRP) showing how strong the signal is and signs (RSRQ) telling how noisy it is, helping your phone pick the best neighborhood. 5G City, however, is faster and smarter, with brighter streetlights (SS-RSRP), clearer signs (SS-RSRQ), and radio detectors (SS-SINR) to find the cleanest path. For speedy travelers (your phone), 5G City adds special beam markers (CSI-RSRP, CSI-RSRQ, CSI-SINR) to guide movement at high speed. It even has clock towers (SFN and Frame Timing Difference) to sync with LTE City when moving between them, and better maps (GNSS, OTDOA, WLAN) for pinpointing your exact location. While LTE City is great, 5G City is built for the future - faster, smarter, and better connected. [In a Nutshell: LTE is good, but 5G City is faster, smarter, and better at keeping devices connected and on the right path.]
LTE and 5G UE Measurements. On the left, LTE City is depicted in black and white caras with basic signal measurement tools like dim streetlights (RSRP) and simple road signs (RSRQ). A neutral smartphone character is measuring signals with older tools, representing slower, less advanced technology. On the right, 5G City is colorful and futuristic, showcasing advanced measurement tools like bright streetlights (SS-RSRP), clear high-tech signs (SS-RSRQ), and advanced radio detectors (SS-SINR). The happy smartphone character in 5G City is actively measuring signals with modern, high-speed tools like beam markers (CSI-RSRP, CSI-RSRQ, CSI-SINR) and navigation aids (GNSS, OTDOA, WLAN). A prominent clock tower (SFN and Frame Timing Difference) connects the two cities, symbolizing synchronization between LTE and 5G.
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- SS-RSRP
- SS-RSRQ
- SS-SINR
- CSI-RSRP
- CSI-RSRQ
- CSI-SINR
- SFN and Frame Timing Difference
- Other 5G NR UE Measurements
SS-RSRP
resources
Synchronization Signal - Reference Signal Received Power (SS-RSRP) measures the average power received from a synchronization signal and plays a vital role in cell selection, reselection, and mobility. It evaluates the strength of synchronization signals received by a device, helping it choose the best cell to connect to, manage mobility, and optimize power usage. SS-RSRP can be reported at two levels: Layer 1 for quick actions like switching between beams, and Layer 3 for longer-term decisions like handovers. It calculates the average power in milliwatts (mW), considering only the useful parts of the signal, and adapts based on the frequency range, using a single antenna for lower frequencies and multiple antennas for higher ones. Filtering improves accuracy by reducing noise and signal fluctuations differently at each layer. While similar to LTE’s measurements, 5G NR improves minimum values for machine communication and extends maximum values to account for beamforming technologies. [In a Nutshell: SS-RSRP measures signal strength to help devices select cells, manage mobility, and improve efficiency, with advanced filtering and beamforming in 5G.]
Imagine SS-RSRP as the brightness of streetlights in a city. Your phone is like a traveler walking through neighborhoods, and the brighter the streetlight, the easier it is to see and choose the best path. In LTE City, the streetlights are basic, but in 5G City, they are smarter and adapt to different types of streets: on narrow roads, a single light is enough, while on wide highways, clusters of lights work together for better coverage. These lights help the traveler decide where to go quickly for short moves (Layer 1) and plan long-term routes (Layer 3). By focusing only on the useful light (ignoring flickers), the traveler can make the best decisions, ensuring smooth and safe movement. [In a Nutshell: SS-RSRP is like streetlight brightness, guiding devices to choose the best path and stay connected efficiently.]
SS-RSRP in 5G NR illustrated with adaptive streetlights representing signal strength, varying in brightness for different road types: brighter clusters for highways and single lights for narrow streets. A device confidently navigates the city, guided by these advanced streetlights. The scene emphasizes smart filtering and advanced technologies like beamforming, showcasing a clear and well-lit cityscape.
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5G NR SS-RSRP 
SS-RSRQ
Synchronization Signal - Reference Signal Received Quality (SS-RSRQ) evaluates the signal quality relative to the total received power, including interference and noise. It measures the quality of synchronization signals by comparing their strength (SS-RSRP) to the overall power (RSSI) received. This is calculated as SS-RSRQ=SS-RSRP/(RSSI/N), where N is the number of resource blocks used for measurement. Unlike LTE, which calculates RSRQ using cell-specific reference signals (CRS), 5G NR uses synchronization signals (SSS), making it adaptable to 5G’s beam-centric architecture. This flexibility allows RSSI and SS-RSRP to be measured from different symbols, enabling 5G to report SS-RSRQ as either positive or negative values, whereas LTE always reported it as negative. SS-RSRQ supports cell selection, reselection, and mobility decisions, with measurements restricted to specific time slots configured by the network for improved accuracy and efficiency. [In a Nutshell: SS-RSRQ measures signal quality by comparing signal strength to overall power, helping devices choose the clearest, most efficient connections in 5G.]
Imagine SS-RSRQ as the “cleanliness” of a street, where your phone, like a traveler, checks not just how bright the streetlights are (SS-RSRP) but how clear and uncluttered the street feels compared to overall noise and traffic (RSSI). In LTE City, this could only be assessed on major roads, making it less flexible. In 5G City, the traveler can evaluate smaller streets and quieter areas, providing a more accurate picture. Sometimes streets feel very clean (positive values), while other times they might still be a bit cluttered (negative values). This helps the traveler choose not just the brightest path but the one that ensures the smoothest journey. [In a Nutshell: SS-RSRQ is like street cleanliness, helping devices find the clearest, least cluttered paths for a better connection.]
SS-RSRQ in 5G NR as a street with various levels of cleanliness. One part of the street is clean and well-maintained, symbolizing high SS-RSRQ (good signal quality). Another part is cluttered with trash and debris, symbolizing low SS-RSRQ (poor signal quality).
- Search Forum 5G NR SS-RSRQ
SS-SINR
Synchronization Signal - Signal to Interference and Noise Ratio (SS-SINR) measures the ratio of desired signal power to interference and noise, assessing the quality of synchronization signals. This metric is critical for mobility procedures in connected mode, helping the network evaluate signal clarity in the presence of interference. SS-SINR is optional for User Equipment (UE) and must be explicitly supported for different frequency ranges. These measurements are limited to specific time windows defined by the SS/PBCH Block Measurement Time Configuration (SMTC). Unlike LTE, where SINR was not tied to synchronization signals, 5G NR introduces SS-SINR as a new metric for enhanced interference management and beam-centric operations. Results can be positive or negative (in dB) and use equal-power reference signals for accuracy. The approach varies by frequency range, using single antennas for lower frequencies and antenna arrays for higher ones. [In a Nutshell: SS-SINR measures how clearly the signal stands out over interference, ensuring reliable mobility and advanced beam operations in 5G.]
Imagine SS-SINR as the clarity of a conversation in a noisy room. Your phone, like a listener, focuses on the person speaking (signal) while tuning out the background chatter and noise (interference). In LTE City, there wasn’t a way to measure how clear the speaker’s voice was for synchronization signals, but in 5G City, this is now possible with SS-SINR. It helps the listener decide whether they can hear well enough to stay or need to move closer to the speaker or find a quieter spot. The clarity check adapts based on the room size, with smaller setups needing a single listener and larger rooms requiring groups of listeners (antennas) working together to hear more clearly. [In a Nutshell: SS-SINR is like checking how clearly you can hear a speaker in a noisy room, helping your phone find the best connection in interference-heavy areas.]
5G NR SS-SINR as a conversation in a noisy room, where a 5G NR device tries to listen to a person speaking (representing the desired signal) in a room filled with background noise like multiple people talking loudly, music playing, and general chaos (representing interference and noise). The device holds a sound meter or earphones to symbolize focusing on the desired signal.
- Search Forum 5G NR SS-SINR
CSI-RSRP
Channel State Information - Reference Signal Received Power (CSI-RSRP) measures the received power of CSI reference signals, assessing the signal strength to support mobility, power control, and beam management in connected mode. These measurements are provided at Layer 1 for fast adjustments like beam switching and at Layer 3 for long-term operations, such as mobility decisions. CSI-RSRP calculates the average power of specific resource elements linked to CSI signals. In 5G NR, it supports both Layer 1 (fast-beam switching) and Layer 3 (channel quality reporting), essential for precise beamforming and mobility management. Filtering improves accuracy at both layers—Layer 1 reduces noise, while Layer 3 smooths out short-term variations. Unlike LTE, where RSRP was based on CRS, 5G ties this metric to CSI signals, enabling more precise, beam-based measurements. Reports use 7-bit absolute values for the strongest signal and 4-bit differential values for others, enhancing reporting efficiency and supporting advanced 5G features like multi-antenna configurations. [In a Nutshell: CSI-RSRP measures signal strength for beamforming and mobility, enabling fast adjustments and efficient reporting in 5G.]
Imagine CSI-RSRP as measuring the strength of spotlights on a stage. In LTE City, the lights were fixed and evenly spread, offering only a general view of the stage. In 5G City, the spotlights are smarter and focus on specific areas to guide performers (your phone) precisely. Layer 1 measurements are like a stagehand making quick adjustments to keep performers in the light, while Layer 3 acts like a director planning the overall lighting for a smooth performance. This smarter spotlight system ensures performers stay visible and coordinated, especially when multiple spotlights (antennas) work together for a seamless show. [In a Nutshell: CSI-RSRP is like smart spotlights, ensuring your phone stays perfectly lit and connected on the 5G stage.]
5G NR CSI-RSRP is like measuring the strength of spotlights on a stage. The scene depicts a theater stage where spotlights focus on performers (representing smartphones). Some spotlights are adjusted by stagehands (representing Layer 1 measurements) to keep the performers perfectly lit, while a director in the background (representing Layer 3 measurements) manages the overall lighting plan for a smooth performance. The spotlights symbolize CSI signals, with labels like ‘CSI-RSRP = Spotlight Strength,’ ‘Layer 1 = Quick Adjustments,’ and ‘Layer 3 = Long-Term Planning.’ This analogy explains how 5G NR ensures precise, beam-based signal strength for mobility and beam management.
- Search Forum 5G NR CSI-RSRP
CSI-RSRQ
Channel State Information - Reference Signal Received Quality (CSI-RSRQ) evaluates the quality of CSI reference signals, comparing their signal strength (CSI-RSRP) to the overall power (RSSI), which includes interference and noise. It is calculated as CSI-RSRQ=CSI-RSRP/(RSSI/N), where N is the number of resource blocks used for the measurement. Unlike CSI-RSRP, this metric is not used for reporting channel state information but is critical for mobility procedures. This measurement is tied to specific CSI reference signal transmissions (antenna port 3000) and supports precise network decisions with 7-bit reporting for absolute values. While RSRQ existed in LTE, 5G NR adapts it for CSI-based measurements, enhancing its role in beam-centric operations and advanced mobility management. [In a Nutshell: CSI-RSRQ measures signal quality compared to total power, ensuring precise mobility decisions in 5G’s beam-focused architecture.]
Imagine CSI-RSRQ as checking the “cleanliness” of a spotlight on a stage. While CSI-RSRP measures how bright the spotlight is, CSI-RSRQ checks how clear and focused it is compared to the overall stage brightness, including distractions like fog or other lights (interference and noise). In LTE City, this cleanliness check existed but wasn’t tied to advanced, focused spotlights. In 5G City, with smarter, beam-specific spotlights, the clarity check is more precise, helping performers (your phone) decide if the beam is clean and reliable enough to stay in or if a switch to a better beam is needed. This ensures smooth, high-quality performances, even under challenging conditions. [In a Nutshell: CSI-RSRQ is like checking the clarity of a spotlight to ensure your phone stays in the cleanest, most focused beam.]
5G NR CSI-RSRQ as checking the cleanliness of a spotlight on a stage. A bright spotlight shines on a performer (the smartphone), surrounded by faint fog and dim lights (interference and noise). A 5G NR device inspects the spotlight’s clarity with a magnifying glass, while another measures its brightness (CSI-RSRP). In this analogy CSI-RSRQ represents Spotlight Cleanliness and CSI-RSRP represents Spotlight Brightness.
- Search Forum 5G NR CSI-RSRQ
CSI-SINR
Channel State Information - Signal to Interference and Noise Ratio (CSI-SINR) calculates the signal-to-interference-plus-noise ratio for CSI reference signals, comparing the desired signal’s power to the combined interference and noise. It is critical for mobility procedures in connected mode, helping the network maintain reliable connections under interference. CSI-SINR is an optional feature that must be explicitly supported and declared by the UE for different frequency ranges. These measurements rely on CSI reference signal transmissions (antenna port 3000) and use a 7-bit reporting format for absolute values, similar to SS-SINR mappings. This measurement did not exist in LTE and is unique to 5G NR, enabling advanced interference management and improving beam-based mobility decisions and network performance. [In a Nutshell: CSI-SINR measures how well the signal stands out from interference, ensuring reliable connections and better mobility in 5G.]
Imagine CSI-SINR as evaluating how clearly you can hear a performer on stage amidst a noisy audience. While CSI-RSRP measures how loud the performer’s microphone is, and CSI-RSRQ checks how focused the spotlight is on them, CSI-SINR determines how much of their voice stands out against the background chatter (interference and noise). In 5G City, this clarity check is new and essential, ensuring the performer’s voice is always clear, even in a noisy or crowded environment. This helps your phone decide whether to stay with the current performer or switch to a clearer one, ensuring the best listening experience (reliable connection) at all times. [In a Nutshell: CSI-SINR is like checking if the performer’s voice is loud and clear above the noise, ensuring your phone stays connected to the best signal.]
5G NR CSI-SINR evaluates the clarity of a performer’s voice on stage amidst a noisy audience. The scene depicts a theater with a performer (representing the desired signal) speaking into a microphone, while a noisy audience (representing interference and noise) creates chatter and distractions. A 5G device in the audience, wearing headphones, analyzes the clarity of the performer’s voice. In this analogy, CSI-RSRP represents Microphone Loudness, CSI-RSRQ represents Spotlight Focus, and CSI-SINR represents Voice Clarity.
- Search Forum 5G NR CSI-SINR
SFN and Frame Timing Difference
SFN and Frame Timing Difference (SFTD) measurements are critical when 4G and 5G base stations are not synchronized in time, particularly in non-standalone (NSA) architectures, where LTE and 5G NR cells work together. These measurements enable the device to report the System Frame Number (SFN) and frame timing differences between LTE (E-UTRA) and 5G NR cells. This information is essential for configuring measurement windows during operations like secondary cell addition. Defined in both LTE (TS 36.214) and 5G NR (TS 38.215), SFTD allows primary cells in one technology to request timing measurements from cells in the other. SFTD support depends on duplexing modes (e.g., FDD or TDD) and must be explicitly declared by the UE. The measurement results include cell IDs, SFN offsets, and frame boundary offsets, ensuring efficient interworking and seamless communication between LTE and 5G. This feature did not exist in LTE alone but is crucial for non-standalone 5G setups, where both LTE and 5G operate simultaneously. [In a Nutshell: SFTD ensures LTE and 5G schedules are aligned, enabling seamless communication and coordination in non-standalone setups.]
Imagine LTE and 5G NR are two train systems in NSA City, running on different schedules. SFN and Frame Timing Difference (SFTD) is like a conductor checking the clocks at both train stations to ensure the trains align perfectly for passengers switching between them. If the trains are out of sync, passengers might miss their connection. By reporting the timing differences between the two systems, SFTD ensures the schedules are adjusted, allowing seamless transfers. While LTE trains didn’t need this feature on their own, it’s essential in NSA City, where both train systems need to operate smoothly together. [In a Nutshell: SFTD is like a conductor syncing train schedules, ensuring seamless transfers between LTE and 5G trains.]
The 5G NR concept of SFN and Frame Timing Difference (SFTD) is illustrated as syncing train schedules in NSA City. The scene features two train stations: one labeled ‘LTE Station’ and the other ‘5G NR Station,’ with trains symbolizing the LTE and 5G networks. A conductor, representing SFTD, holds two large clocks, aligning their times to ensure seamless connections between the train systems. Passengers, symbolizing devices, are shown smoothly transitioning between the trains.
- Search Forum 5G NR SFN and Frame Timing Difference
Other 5G NR UE Measurements
5G introduces several additional measurements that extend LTE capabilities, enhancing interworking, testing, and positioning services. For inter-system operations, 5G supports LTE measurements like RSRP, RSRQ, and SINR for tasks such as cell reselection and handovers across technologies. A new 5G-specific measurement, SS-RSRPB (Synchronization Signal - Reference Signal Received Power per Branch), is used during device testing for Frequency Range 2, enabling detailed reporting of RSRP for each receive path. For location-based services, Reference Signal Time Difference (RSTD) supports the OTDOA positioning method, leveraging the timing differences between LTE cells to improve accuracy. This is complemented by Global Navigation Satellite System (GNSS) measurements, which use the UE’s GNSS receiver for enhanced positioning, and IEEE 802.11 WLAN RSSI measurements, which provide WLAN-based location data. These capabilities enhance 5G’s versatility in mobility, testing, and location-based services, demonstrating its advancement over LTE. [In a Nutshell: 5G extends LTE’s measurements and adds advanced tools for better mobility, testing, and location accuracy.]
Imagine LTE City had basic tools to help travelers find their way, like simple road signs (RSRP, RSRQ, and SINR) to guide movement and decisions. 5G City, however, upgrades these tools while adding advanced features for a smarter experience. For example, SS-RSRPB is like having detailed maps for each lane on a multi-lane highway, helping drivers (devices) navigate more precisely during tests. For location services, RSTD acts like a set of synchronized clocks in different parts of the city, allowing travelers to calculate their exact position using timing differences. GNSS works like a satellite-based GPS system, and WLAN RSSI is like using nearby Wi-Fi signals as markers to pinpoint your location. These enhancements make 5G City far more equipped for seamless travel and accurate navigation, outshining LTE City’s older system. [In a Nutshell: 5G adds smarter tools like detailed maps, synchronized clocks, and Wi-Fi markers for precise mobility and navigation.]
5G NR Other UE Measurements emphasize 5G City with advanced tools for navigation and connectivity. The scene depicts a bustling 5G City featuring detailed highway maps (representing SS-RSRPB), synchronized city clocks (symbolizing RSTD for OTDOA positioning), satellite GPS markers (GNSS), and Wi-Fi signal markers (WLAN RSSI). SS-RSRPB represents Lane Maps, RSTD represents Clocks, and GNSS represents Satellite GPS, showcasing 5G’s innovative capabilities in mobility and positioning.
- Search Forum 5G NR Other 5G NR UE Measurements
Quick Summary
- SS-RSRP: Signal Strength (Streetlight Brightness).
- SS-RSRQ: Signal Quality (Road Sign Clarity).
- SS-SINR: Signal Clarity vs. Interference (Radio Station amidst Static).
- CSI-RSRP: Beam Brightness (Spotlight Brightness).
- CSI-RSRQ: Beam Cleanliness (Spotlight Cleanliness).
- CSI-SINR: Beam Clarity amidst Noise (Performer’s Voice amidst a Noisy Audience).
- SFN and Frame Timing Difference: Synchronizing Networks (Conductor Syncing Train Schedules).
- Other 5G NR UE Measurements: Advanced Mobility Tools (Detailed Maps, Clocks, GPS, Wi-Fi Markers).
- RSSI: Total Received Power (Combined Glow of All Streetlights).
- CRS: LTE Reference Signal (Fixed Lamp Post guiding LTE roads).
- SSS: Synchronization Signal (Compass ensuring all devices are aligned).
That’s it. 
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