Does a smartphone use the same hardware to place phone calls as it does when using data to access the internet? How does this process work?


Handsets have a few ways of doing both. It depends on the infrastructure of the network.

If the preferred network is circuit switched, then the handset makes a voice connection that requires a constant low bitrate connection where the voice is placed in a carrier wave.

If the network is IP switched then the voice data can be packetized and therefore doesn’t need a bitstream to maintain the call quality, can burst transmit frames, and route packets in dissimilar paths to react to congestion.

If the network is wifi in a WIFI calling authorized scenario, the same basic rule applies as above but the ISP will handle the transport instead of the carrier.

In each of these examples, a different  logic IC or a different component of an integrated IC is used. These days a gprs cell modem, 802.11, 15 don’t necessarily need to be discrete, but they are segmented, and utilize different protocols to achieve a common task:

Transmit and receive data.While that end is similar, the means is not…and therefor very different technology netchampioned, maintained and steered be different consortiums.

Thank you, it makes a bit more sense. What hardware does the phone use when using LTE or 3G to access the internet then?
Tuhin Gupta

Most North American OEMs use qualcomms Gobi logic because of its flexibility and reach across the spectrum of infrastructure dissimilarity and frequency spectrum allocation. Some hardware designs will use the discrete logic…others will just build it onto their SoC design.

On an iPhone then, is the hardware used to access data the same as the hardware used to make voice calls?
Tuhin Gupta

Well, like I said, today’s logic isn’t like the individual discrete chips on a board like 10 years ago. Logic Systems are designed in a software development environment for chip design , and then etched so they are all integrated on a single ‘assembly’ called a system on a chip.

If you are asking is voice data and IP packet data like website, mail or database data generated in the same pipeline, the answer is yes if it’s Voice that is transported using the TCP/IP on the transport protocol represented by the OSI model.
But circuit switched networks aren’t packet-ized. So for voice communication in that pipeline logic support for a carrier wave that must be produced is utilized and the voice audio is encoded, transported as an audio signal, and then the carrier wave is stripped at the other end. It can’t be chopped up and sent in pieces and reassembled. It is sent sequentially and must be recieved sequentially or your connection gets dropped if the response times out.
With voice data that can be transported in packets…like ‘data on the Internet’ as you put it, this is possible because voice data can be transported the same way….but that is dependent on the current network infrastructure type,
Before voice could be digitally converted, it was transported using a broadcast transmitter and reciever on a carrier wave like radio or TV used to also be broadcast. But radio and TV can also be transported like internet data over the Internet, but it can so be broadcast without having to be digitally converted…just like voice data can…and that energy can be sent through space in a different medium than an IP data network, and is usually referred to as ‘Legacy RF’
So, can a voice transmission be packaged up and transported on the same silicon logic as ‘internet data’? Yes…when it is transmitted over the network, a packet switched network.

But if the handset is on a circuit switched network, then it has to be created using a different technology, different protocol using different hardware logic. But that logic can physically reside on the same logic board and even exist on the same logic cluster as the other hardware. Just like a microprocessor can have SRAM and caches for data and caches for instructions and is built on its core. They aren’t the same because the microcode is different, they are physically separated, and have different functions but are still part of the processor physically.

Here is QComms info graphic telling how it supports both legacy RF and GPRS data transmission on its snapdragon.Perhaps this can help visualize better the hardware being same but different when it comes to circuit switched and packet switched voice.

Does a smartphone use the same hardware to place phone calls as it does when using data to access the internet? How does this process work?

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