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2.2.1 DUPLEXER
Link Duplexer is a device to transfer Down Link signal and Up Link Signal by
using one port.
Down Link signal received Antenna from the BTS, it remove the other band signal
and transfer LNA signal.
Up Link signal is being filtered the last and come out forward Base Station.
The signal frequency relaying toward terminal from Base Station is 1850 MHz ~
1910Mhz.
The signal frequency relaying toward Base Station from the terminal is KTF:1930
MHz~1990 MHz.
Tx/Rx Isolation is more than 50 dBc.
2.2.2 LNA
LNA is as a AMP amplifying first step received the weak signals through the
DUPLEXER, has a excellent specific device of NF(1dB under)
It improves the whole system of NF and IP3 is rather high that can come out the
stable output.
2.2.3 DOWN CONVERTER
Down Converter would convert IF signal from low-noise amplified signal for
filtering SAW Filter having a good SCIRT.
In case of converting into IF signal it would be easier the process than RF signal,
it can receive excellent selectivity only passing through the setting frequency range.