3. CDMA system synchronization

CDMA systems can only be deployed with good synchronization between base stations. To achieve this, the CDMA system adds a special code known as "pseudorandom noise" (PN offset) to the code specific to each user signal. Base stations differ from one another in that they transmit different parts of this code at different times. In other words, base stations transmit versions of the same code that differ only in phase. To ensure that this time offset remains constant, and that the PN codes remain unique, the base stations must be synchronized on a common time base. The main method of synchronization is to use the Global Positioning System (GPS) satellite network. However, in the event of GPS system failure, CDMA network base stations rely on an alternative synchronization source. Depending on the base station's location, it may be possible to call on the Loran_C (Long Range Navigation C)...