Synchronization
Femtocell synchronization is an important aspect of their
design. Many aspects of their operation require reasonable
levels of femtocell synchronization. 3GPP specifies that base
station frequencies need to be very accurate, and there needs
to be close synchronization with precise clock signals.
Although Release 6 of the 3GPP standard relaxed the
requirements for femtocell synchronization, and further
relaxation may be possible in the future, methods of providing
sufficient femtocell synchronization provide a challenge at the
design stages.