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5G Networks and Voice over New Radio (VoNR)

5G represents the fifth generation of mobile networks, offering unprecedented speeds, ultra-low latency, and massive connectivity. VoNR (Voice over New Radio) is the native voice solution for 5G networks.

What is 5G?​

5G = Fifth Generation mobile network technology

Key Capabilities​

1. eMBB (Enhanced Mobile Broadband)​

  • Speed: Up to 20 Gbps (peak), 1+ Gbps typical
  • Use Cases: 4K/8K video, AR/VR, cloud gaming
  • Improvement: 10-100x faster than 4G

2. URLLC (Ultra-Reliable Low-Latency Communications)​

  • Latency: < 1 millisecond
  • Reliability: 99.999% availability
  • Use Cases: Autonomous vehicles, remote surgery, industrial automation

3. mMTC (Massive Machine-Type Communications)​

  • Density: 1 million devices per km²
  • Use Cases: IoT, smart cities, sensors
  • Efficiency: Low power, long battery life

5G Network Architecture​

5G Standalone (SA) Architecture​

Key Differences from 4G​

Component4G LTE5G NR
Base StationeNodeBgNB (gNodeB)
CoreEPC5GC (Service-Based)
Mobility MgmtMMEAMF
Session MgmtCombined in MMESMF (separate)
User PlaneS-GW/P-GWUPF
Subscriber DBHSSUDM
PolicyPCRFPCF
ArchitectureMonolithicService-Based (SBA)

5G Core Network Components​

AMF (Access and Mobility Management Function)​

The "brain" for mobility and access control.

Functions:

  • Registration management
  • Connection management
  • Mobility management
  • Authentication and authorization
  • Access control
  • Security anchoring

Analogous to: MME control plane in 4G

SMF (Session Management Function)​

Manages PDU (Protocol Data Unit) sessions.

Functions:

  • Session establishment, modification, release
  • IP address allocation
  • QoS management
  • Policy enforcement
  • Routing decisions
  • Charging data collection

Analogous to: P-GW control plane in 4G

UPF (User Plane Function)​

Handles actual user data traffic.

Functions:

  • Packet routing and forwarding
  • Traffic inspection
  • QoS enforcement
  • Buffering
  • Lawful intercept
  • Gateway to external networks

Analogous to: S-GW/P-GW user plane in 4G

Key Feature: Can be deployed at network edge for low latency!

UDM (Unified Data Management)​

Master subscriber database.

Functions:

  • Subscriber authentication credentials
  • Subscription data
  • Service data
  • Policy data
  • User context

Analogous to: HSS in 4G

PCF (Policy Control Function)​

Policy and charging control.

Functions:

  • QoS policies
  • Charging rules
  • Network slicing policies
  • Application policies

Analogous to: PCRF in 4G

AUSF (Authentication Server Function)​

Handles authentication.

Functions:

  • User authentication
  • Key management
  • Security context

New in 5G: Separated from UDM for better security

Network Function Repository (NRF)​

Service discovery.

Functions:

  • NF registration
  • NF discovery
  • Service discovery
  • Load balancing info

New in 5G: Enables service-based architecture

NEF (Network Exposure Function)​

Exposes network capabilities to external applications.

Functions:

  • API gateway
  • Authentication for external apps
  • Traffic influence
  • QoS negotiation

New in 5G: Enables 5G APIs for third parties

Service-Based Architecture (SBA)​

5G Core uses Service-Based Architecture where network functions communicate via APIs.

Service-Based Interfaces​

All interfaces start with "N":

  • Nsmf: SMF services
  • Namf: AMF services
  • Nudm: UDM services
  • Npcf: PCF services
  • Nausf: AUSF services

Benefits:

  • ✅ Microservices architecture
  • ✅ Scalability
  • ✅ Flexibility
  • ✅ Cloud-native deployment
  • ✅ Network slicing support

VoNR (Voice over New Radio)​

VoNR is the native voice solution for 5G networks, similar to how VoLTE works for 4G.

VoNR Overview​

Key Characteristics​

FeatureVoLTE (4G)VoNR (5G)
NetworkLTE5G NR
Voice QualityAMR-WB (HD)EVS codec (Super HD)
Call Setup1-2 seconds< 1 second
Latency~50ms< 10ms
Core NetworkEPC + IMS5GC + IMS
Mobility MgmtMMEAMF
Session MgmtMMESMF
QoSQCI5QI

VoNR Call Flow​

EVS Codec (Enhanced Voice Services)​

Superior to AMR-WB used in VoLTE.

Features:

  • Bandwidth: Supports narrow-band to super-wideband (16 kHz+)
  • Bitrate: 5.9 to 128 Kbps (adaptive)
  • Quality: Superior voice quality
  • Robustness: Better error resilience
  • Efficiency: Better compression

Audio Quality Comparison:

  • AMR-NB (3G): 8 kHz sampling - Standard phone quality
  • AMR-WB (VoLTE): 16 kHz sampling - HD Voice
  • EVS (VoNR): 16-32 kHz sampling - Super HD Voice

5QI (5G QoS Indicator)​

Similar to QCI in 4G, but more flexible.

Common 5QI Values​

5QIPriorityPacket DelayPacket LossUse Case
120100 ms10⁻²VoNR
240150 ms10⁻³Video call
550100 ms10⁻⁶IMS signaling
990300 ms10⁻⁶Video streaming
796510 ms10⁻²V2X (Vehicle)
806810 ms10⁻⁶Low latency eMBB
821910 ms10⁻⁴AR/VR

5QI 1: Highest priority for VoNR!

Network Slicing​

One of the most powerful features of 5G is Network Slicing - creating multiple virtual networks on the same physical infrastructure.

Slice Examples​

Slice 1 - Consumer Mobile Broadband:

  • High speed data
  • Best-effort delivery
  • Large bandwidth

Slice 2 - Mission-Critical Services:

  • Ultra-low latency
  • High reliability
  • Guaranteed QoS

Slice 3 - IoT:

  • Massive connections
  • Low power
  • Small data packets

Benefits:

  • ✅ Customized network per use case
  • ✅ Resource optimization
  • ✅ Isolation (one slice doesn't affect others)
  • ✅ New business models

5G Spectrum Bands​

5G uses three spectrum ranges:

FR1 (Frequency Range 1): Sub-6 GHz​

  • Bands: 600 MHz - 6 GHz
  • Coverage: Wide area (similar to 4G)
  • Speed: 100-900 Mbps
  • Penetration: Good (buildings, walls)
  • Use: Urban, suburban, rural

FR2 (Frequency Range 2): mmWave​

  • Bands: 24-100 GHz
  • Coverage: Small cells (100-300m)
  • Speed: Multi-Gbps (up to 20 Gbps)
  • Penetration: Poor (blocked by walls, rain)
  • Use: Dense urban, stadiums, airports

5G vs 4G Comparison​

Feature4G LTE5G NR
Peak Speed1 Gbps20 Gbps
Typical Speed50-100 Mbps200-1000 Mbps
Latency30-50 ms< 1 ms (URLLC)
Connections100K devices/km²1M devices/km²
Mobility350 km/h500 km/h
Spectrum< 6 GHzSub-6 GHz + mmWave
ArchitectureEPC5GC (Cloud-native)
VoiceVoLTEVoNR
SlicingLimitedNative support
Edge ComputingLimitedBuilt-in (MEC)

EPS Fallback (VoLTE Fallback from 5G)​

During early 5G deployment, many networks use EPS Fallback for voice calls.

Why? VoNR not yet widely deployed, so fallback to VoLTE.

Future: Native VoNR everywhere!

5G Deployment Scenarios​

NSA (Non-Standalone)​

5G radio with 4G core.

Characteristics:

  • Quick deployment
  • Uses existing 4G core
  • 5G data speeds
  • Voice via VoLTE (4G)

SA (Standalone)​

Pure 5G with 5G core.

Characteristics:

  • Full 5G features
  • Network slicing
  • Ultra-low latency
  • Native VoNR
  • Cloud-native architecture

Use Cases​

1. Enhanced Mobile Broadband (eMBB)​

  • 4K/8K video streaming
  • Immersive AR/VR
  • Cloud gaming
  • 360° video

2. Ultra-Reliable Low-Latency (URLLC)​

  • Autonomous vehicles (V2X)
  • Remote surgery
  • Industrial automation
  • Drone control

3. Massive IoT (mMTC)​

  • Smart cities (sensors, lighting, parking)
  • Smart agriculture
  • Smart utilities (meters)
  • Wearables and health monitoring

5G Security Enhancements​

Improvements over 4G​

  1. Enhanced Authentication

    • 5G-AKA (Authentication and Key Agreement)
    • Stronger encryption

  2. User Privacy

    • SUPI (Subscription Permanent Identifier) protection
    • SUCI (Subscription Concealed Identifier)
    • IMSI catchers prevented

  3. Service-Based Architecture Security

    • OAuth 2.0 for API security
    • TLS for all NF communications

  4. Network Slicing Security

    • Isolation between slices
    • Per-slice security policies

Future: 5G Evolution​

What's Next?​

5G-Advanced (Release 18+):

  • AI/ML integration
  • Improved energy efficiency
  • XR (Extended Reality) optimization
  • Sidelink enhancements

6G (2030+):

  • Terahertz frequencies
  • AI-native networks
  • Holographic communications
  • 100+ Gbps speeds
  • Sub-millisecond latency

Summary​

5G Key Features​

  • ✅ Speeds: Up to 20 Gbps (100x faster than 4G)
  • ✅ Latency: < 1ms for URLLC
  • ✅ Connections: 1M devices per km²
  • ✅ Network Slicing: Multiple virtual networks
  • ✅ Cloud-Native: Microservices architecture
  • ✅ Spectrum: Sub-6 GHz + mmWave

VoNR Benefits​

  • ✅ Super HD Voice: EVS codec
  • ✅ Faster Call Setup: < 1 second
  • ✅ Lower Latency: < 10ms
  • ✅ Native 5G: No fallback needed
  • ✅ Better Quality: Superior to VoLTE

Architecture Evolution​