5G NR, short for 5G New Radio, is the radio access technology standardized by 3GPP for fifth-generation mobile networks. In 5G networks, NR defines the air interface between the user device and the base station, called a gNB: its waveforms, numerology, frame structure, channel coding, beamforming and the protocols that schedule radio resources.
NR was designed as a single flexible radio for very different services: high-speed mobile broadband, ultra-reliable low-latency communication and massive numbers of low-power devices. First specified in 3GPP Release 15 in 2017 and 2018, it has been extended in later releases and operates across bands from below 1 GHz to above 50 GHz.
How 5G NR transmits data over the air
Like LTE, 5G NR uses OFDM (orthogonal frequency division multiplexing), which splits a wide channel into many narrow subcarriers that carry data in parallel. NR uses CP-OFDM in the downlink and offers both CP-OFDM and DFT-s-OFDM in the uplink, the latter improving power efficiency for devices at the cell edge.
The key innovation is scalable numerology. Instead of LTE’s fixed 15 kHz subcarrier spacing, NR allows spacings of 15, 30, 60, 120 kHz and higher. Wider spacing shortens each symbol and slot, which lowers latency and tolerates the phase noise of high frequencies, while narrower spacing suits large cells and low bands.
| Subcarrier spacing | Slot duration | Typical use |
|---|---|---|
| 15 kHz | 1 ms | Low bands, LTE coexistence |
| 30 kHz | 0.5 ms | Mid band such as 3.5 GHz |
| 60 kHz | 0.25 ms | Mid band or mmWave, low-latency use |
| 120 kHz | 0.125 ms | Millimeter-wave data channels |
Data channels use LDPC codes, which handle large blocks at high throughput, while control channels use polar codes. Modulation scales up to 256-QAM, with 1024-QAM added in later releases for very good channel conditions.
Frequency ranges and channel bandwidths
3GPP splits NR spectrum into two frequency ranges. FR1 covers roughly 410 MHz to 7.125 GHz and carries most commercial 5G traffic, especially in the 3.3 to 4.2 GHz mid band. FR2 covers millimeter-wave spectrum from about 24 GHz upward, where very wide channels deliver multi-gigabit peak speeds over short distances.
| Property | FR1 | FR2 (mmWave) |
|---|---|---|
| Frequency range | About 410 MHz-7.125 GHz | About 24.25-71 GHz |
| Maximum channel bandwidth | 100 MHz | 400 MHz |
| Typical cell radius | Hundreds of meters to many kilometers | Roughly 100-300 m |
| Building penetration | Moderate to good | Poor |
| Main role | Coverage and capacity | Hotspot capacity, fixed wireless |
Beamforming and massive MIMO in 5G NR
NR was built around beam-based operation. The gNB transmits a set of synchronization signal blocks in different directions, the device reports the strongest beam, and both sides refine the beam during the connection. This beam management is essential in FR2, where high path loss must be offset by antenna gain.
In the mid band, operators deploy massive MIMO radios with 32 or 64 transmit and receive chains. These shape narrow beams toward individual users and serve several users on the same frequency at the same time through multi-user MIMO, which multiplies cell capacity without new spectrum.
5G NR compared with LTE
5G NR is an evolution of LTE’s OFDM foundation rather than a complete break, but it removes several LTE constraints. Most notably, NR avoids always-on reference signals, which cuts interference and energy use, and supports flexible TDD slot formats that change the uplink-downlink split per slot.
| Aspect | LTE | 5G NR |
|---|---|---|
| Subcarrier spacing | Fixed 15 kHz | Scalable, 15 kHz and higher |
| Maximum carrier bandwidth | 20 MHz | 100 MHz in FR1, 400 MHz in FR2 |
| Air interface latency target | About 10 ms | About 1 ms for URLLC |
| Data channel coding | Turbo codes | LDPC codes |
| Always-on reference signals | Yes | Minimized, lean carrier |
| Beam management | Limited | Native in all bands |
Deployment options for 5G NR
NR can run in non-standalone (NSA) mode, anchored on an LTE carrier and a 4G core, or in 5G standalone (SA) mode with its own 5G core network. Most early networks launched in NSA because it reused existing infrastructure; SA is needed for features such as network slicing and the lowest latency.
| Mode | Control plane anchor | Core network | Main benefit |
|---|---|---|---|
| NSA (EN-DC) | LTE | 4G EPC | Fast launch, reuses LTE |
| SA | NR | 5G core | Slicing, lower latency, new services |
| Dynamic spectrum sharing | LTE and NR in one band | Either | Gradual migration of low bands |
Later 3GPP releases broadened NR into NR RedCap for mid-tier devices such as wearables and industrial sensors, sidelink for direct device-to-device communication, positioning, and non-terrestrial networks. Release 18 marks the start of 5G-Advanced.
Limitations and misconceptions about 5G NR
- Peak speeds are theoretical. Real throughput depends on spectrum held, load, distance and device category; typical mid-band speeds are far below headline peaks.
- The 5G icon is not proof of NR performance. A device may show 5G while most traffic still flows over an LTE anchor in NSA mode.
- Low latency requires more than NR. The core network, transport and server location must also be close to the user.
- Uplink remains the weaker link, because device transmit power is limited, which affects video uploads and cell-edge coverage.
Stripped to the essentials
5G NR is the radio language of 5G. A 5G phone and a mobile mast use it to talk to each other over the air. It sets the rules for how data is packed into radio waves. It also decides how the mast points its signal at each phone.
Compared with 4G, this language is more flexible. It can use very wide channels and react faster. It can also aim signals like a spotlight. That is why one 5G network can serve a video call, a factory robot and a home internet box.
Where it is applied
A mobile operator upgrades a busy urban site with a 64T64R massive MIMO radio using a 100 MHz NR carrier at 3.5 GHz with 30 kHz subcarrier spacing. The previous LTE carrier on the site had 20 MHz in a lower band.
During evening peak, the NR cell schedules several users on the same frequency with multi-user MIMO, and typical downlink speeds in the area rise from a few tens of megabits per second to several hundred megabits per second. After the operator moves the site to standalone mode with a 5G core, round-trip latency to a nearby edge server drops noticeably, making cloud gaming and live video uploads practical in the district.