03 February 2020

    Megan Ellis

    Factors that affect voice calls

    From the weather to load shedding, we look at the various things that can impact the quality of a voice call.

    There are a variety of ways that a voice call’s quality can be impacted – from the clarity of the sound and broken transmission to delays between input and output. But what are the factors that cause these issues? Here’s all you need to know.

    How devices affect call quality

    The biggest factor that affects call quality is the device making or receiving the call. If a device on one end of the call is extremely old, damaged or of low quality, it becomes very difficult to hear each other over the call. This also makes it more likely for there to be interference, such as static noise.

    If you’re consistently struggling to make phone calls, despite changing locations and calling different numbers, your device might be at fault. To test whether this is the case, borrow a friend’s SIM card and make a call using your device. If there’s still an issue, your phone is most likely the problem.

    How location impacts call quality

    Your location can affect the quality of both traditional voice calls and Voice over Internet Protocol (VoIP) calls. For example, when you are in a remote area that is far away from your provider’s cell towers, the weak signal will result in lower voice call quality. This is why you’ll experience low or no signal in rural areas or remote parts of national highways.

    The infrastructure around your location can also affect the signal. For example, if you are surrounded by reinforced concrete (such as in an underground parking basement), your signal will weaken. Natural barriers such as mountains and hills can also affect the signal. Usually, moving to a location higher up with fewer surrounding obstructions will improve signal and call quality. 

    When it comes to VoIP calls, your phone still needs to be able to connect with the internet. Therefore, areas that obstruct wireless internet signals will also result in lower call quality or ‘dead zones’ where you have no signal at all.

    How weather can affect call quality

    Certain weather can also affect the stability and quality of your call signal. For example, strong rain can affect your voice calls since cell tower signals do not travel well through water. The water vapour from heavy fog can also affect your signal.

    Meanwhile, dense and low storm clouds affect the signal, too, since they interfere with the radio waves that carry cell phone signals. Strong winds will not affect the quality of your signal or calls.

    Network congestion and call quality

    VoIP calls can also be affected by network congestion. If the network infrastructure near you is experiencing a high volume of traffic from many users, slower connection speed and instability can be experienced. 

    This is most common during peak connection times, such as early evenings during the week. If you experience ongoing problems, it’s best to lodge a complaint with your provider to bring attention to the issue.

    Can load shedding affect call quality?

    While there are backup batteries and generators for cellphone towers, extended and frequent load shedding can result in these power supplies being completely drained. Once a cell tower goes offline due to a lack of power, your calls are routed through the next closest tower. This increases the distance your signal needs to travel, which can impact call quality significantly. 

    If enough cell towers are affected, you may experience intermittent signal. However, once power has been restored, these issues should resolve. Find out more about how load shedding affects Vodacom’s service in our Vodacom load shedding FAQ.

    Voice call quality and VoLTE

    So do all these factors also affect voice over LTE (VoLTE) connections? Device issues will affect voice calls regardless of connection type. 

    However, when it comes to factors such as congestion, weather and location, the superiority of VoLTE connections over traditional voice or VoIP means that these issues have a much smaller impact on call quality. VoLTE relies on a faster connection which improves call quality overall and makes it more resilient to interference. 

    For more information about Vodacom's VoLTE, go to the Vodacom website.

    Header photo by cottonbro from Pexels

    Megan Ellis