Global LTE deployments are continuing to rise and the technology is gaining ever more market recognition. However, LTE currently possesses a key limitation that the industry is actively looking to resolve – the issue of voice. As it stands, LTE networks can only support data and are incapable of handling voice calls. From a consumer’s perspective, this could be viewed as a rather remarkable omission, considering that traditionally, the key role of mobile operators was to provide voice services. As a result, operators could be left vulnerable to being superseded by OTT providers, such as Skype, in the mobile voice market. This is the view of Paul Beaver, Products Director at wireless device testing company, Anite.

According to Beaver, the industry is increasingly determined to develop a solution which will allow voice calls to be made over LTE networks. Voice over LTE (VoLTE) technology will also enable Operators to pioneer new business models, reinstating them as the primary purveyors of premium voice services.

VoLTE trials are currently being undertaken; with device manufacturers, chipset vendors and operators all testing VoLTE solutions in the laboratory. VoLTE is still in a state of technological infancy; and this has resulted in a diverse range of mobile operator interpretations in regard to how VoLTE should be integrated with networks and devices. These unique requirements mean that here can be no ‘one size fits all’ VoLTE solution for operators. Operators will instead have to rigorously test a diverse range of variable conditions; all of which could potentially impact on their ability to deploy and uphold VoLTE.

Mobile subscribers will continue to expect top quality voice services on their mobile, and a ‘best effort’ Voice over Internet Protocol type service, such as Skype, will not be sufficient. VoLTE must provide a top quality service, or risk gaining a negative perception amongst consumers. Upon VoLTE’s introduction, network signalling levels will naturally escalate and this will put networks under increased strain. Operators will need to prepare for this, and build this scenario into their program of testing.

VoLTE’s ultimate success will be determined by its proficiency in delivering top quality voice services across an all-IP network, on the latest LTE devices. However, cooperation within the mobile industry is a necessity if VoLTE is to emerge as a viable commercial possibility.

According to Beaver, a rigorous testing program will be a decisive factor in determining the success of VoLTE’s introduction – particularly in consideration of the variety of implementations taking place. This could be a costly and labour intensive process. By leveraging lab-based testing, handset manufacturers, chipset vendors and mobile operators can utilise a simulated network environment to test both component interoperability and audio quality. By adopting this method of testing, operators no longer rely on live network testing and expensive, time consuming device field trials. Meticulous VoLTE testing can be performed more easily and at a reduced cost. Lab based testing can help to ensure that VoLTE works as expected and in turn, will maintain mobile operators as the leading service providers in the mobile voice market.