we practically do not reflect on what standard of communication we use, and how in other countries
In the USA there are standards GSM 850/1900, and in Europe - 900/1800
everyone wants to know what is the fundamental difference between the work of these two diapozones
In GSM, channel separation over time and frequency is used. Each subscriber is allocated a small frequency band, on which the phone communicates with the base station. In this case, the "sessions" of data exchange are fixed in time. With a certain simplification, we say that the signal is interrupted, but because of the high frequency of data transmission, the subscriber does not notice this. In real life, interruptions are noticeable except for the characteristic squeaking sound of the speakers, when the phone next to which the call is ringing or the message comes.
Code division of signals is used in CDMA. Each subscriber connected to the base station uses the entire available frequency resource common to all subscribers, and the base station communicates with all simultaneously. The signal from a specific user is allocated by means of code modulation - each subscriber has a specific "code", which allows to separate it from the general radio air.
in russia all cdma operators ceased to exist.
However, in the territory of Donetsk and Lugansk, where gsm operators ceased their work,fas mts life kyivstar the cdma operator of the intrelecom successfully and steadily continues to work
all thanks for attention to the article
