VoLTE will be pervasive in most large markets in the next 1 to 2 years. Voice call quality and handover from 2G/3G to LTE will be a decisive factor for the launch, performance and acceptance of devices/networks.

Voice over LTE (VoLTE) means the delivery of voice over LTE. Rather than using dedicated resources over circuit-switched networks, it uses packet switched (all- IP) network.

LTE is the current evolutionary path for all 2G and 3G networks. Currently network operators have to maintain the existing 2G/3G and LTE footprint and have to buy additional spectrum to deploy LTE services to be able to offer 100% voice coverage. After moving to LTE-only networks, operators can re-farm the existing spectrum to add coverage, throughput and other services. However, to move away entirely from 2G/3G - the primary and the most important use of mobile handsets - VOICE has to be supported over LTE.
VOLTE has several advantages:

  1. Lower latency
  2. Improved battery life
  3. Bandwidth optimization

But at the same time it has some challenges

  1. Higher and less predictable delays
  2. Delay jitter and other network impairments
  3. Echo-canceller performance may be affected
  4. Conversational voice quality and background noise transmission may be impacted

How is it done?

  • VoLTE uses AMR (Adaptive Multi Rate) voice codec
  • Uses a wider bandwidth (50–14000 Hz instead of 300–2400 Hz) resulting in 40% better voice quality
  • Measurement using POLQA® and PESQ® - objective perceptual speech test methods 
    • PESQ® provides a narrowband and a wideband mode 
    • POLQA® provides a narrowband and a super-wideband mode

Which operators support VoLTE in North America?

  • Verizon
  • ATT
  • T-Mobile

How can SGS help?

SGS North America has installed two state-of-the-art Anechoic Acoustic and Background Noise Suppression chambers. This enables us to provide cutting edge services for the Verizon Device Requirements Codec and Voice Quality (VoLTE Audio quality) and Sprint Electro-Acoustics Test plan. In addition to this, SGS North America will be offering services for C.S0056, TS 26.131/132, TS 103.737/738, TS 103.739/740 test specifications. We can help you meet your goal of delivering excellent audio quality by providing R&D services, pre-certification and official certification.

For more information, please contact:

Amy Stripe O’Regan
Global Key Account Manager
16870 W. Bernardo DR,
San Diego California
t: +1 858 592 7100