First, how do phones generally perform on calls?
It is certain that you have been exposed to this message before or seen it on your phone; “No network coverage, only emergency calls”, but have you ever wondered how phones enable us to make emergency calls even in places where there is no service or network coverage! To understand how emergency calls work, we must first understand how the network works in traditional mode in general.
Normally, to make cellular calls, you add a SIM card to your phone or activate the eSIM chip, and then the name of the network appears, usually in the upper right corner of your phone screen, and it automatically starts communicating through network towers in your vicinity to connect to the phone via signals generated by the service provider (the company Contracted to obtain a SIM card), and the signals are transmitted from one tower to another until they end up to the nearest communication tower for the person you are calling, and as you know that all this happens in seconds or in moments, and the closer you are to the signal and communication towers, the more the signal It is powerful, and then traditional calls can be made between you and the other party without problems, but in the case of making emergency calls, the matter is somewhat different.
Modern phones have a technology that allows you to make emergency calls by bouncing signals from the nearest network tower to you, regardless of which network provider you have in your phone.
How do emergency calls work without network coverage?!
As I mentioned earlier, it is not necessary to send the signal through the cell phone tower owned by the telecom company when making any emergency call. In emergency situations, smart phones use the nearest cell tower without looking at the original network provider for the SIM inside the phone, thanks to that There are agreements between local and international service providers whereby using the Emergency Call only option connects you to an available help center as long as the phone can connect to any nearby cell tower.
But of course, it is not subject to agreements or joint cooperation between companies to use the infrastructure, emergency calls must be made under any circumstances. Therefore, it is necessary to know that the role of the SIM card in your phone is limited to authenticating your identity on a specific network, so that this chip carries information about your account with the service provider, and the latter can control whether or not it is possible to make a call via the cellular SIM. The phone, on the other hand, has the means to actually make the call. In simpler terms, a SIM card only allows you to connect to a specific network after verifying that you are associated with it.
Emergency calls do not need any network authentication, so when you make an emergency call any nearby cell tower is used to connect you to the emergency desk without verifying your identity, i.e. the SIM card functionality is bypassed. So you can make emergency calls even when there is no SIM card in the phone, to ensure your safety and ability to access assistance at any time and under any circumstances in cases of extreme necessity. Regardless, this will not always be the case, some countries do not allow emergency calls without a SIM card as this can cause a lot of fake calls that waste time and resources of the emergency services, so having a SIM card is necessary so that the caller can be traced, or at least blocked If he made a lot of dummy calls.
So all of the above can be summed up in that the phone makes emergency calls under any circumstances as long as there is a cell tower close enough to contact the help center. But if you are in a secluded place where there are no cell towers through which the phone can receive and transmit signals, then you will not be able to make emergency calls. So it is necessary for people who travel to explore remote areas and unknown places to have special equipment which helps to provide network coverage by connecting to remote towers. It should also be noted that modern smartphones, such as Apple's iPhone 14, allow communication with emergency services via satellite , bypassing the need for cell towers entirely.
