User Manual

System Description NOTCHCELL Repeater
R-TRON Proprietary & Confidential Page 20
Up Converter
Up Converter consists of Mixer, AMP, BPF, Digital Atten, Analog Atten and RF level detector. Mixer is used to
convert IF (70 MHz) to Down Link Path RF Frequency. BPF is to remove signal out of service range. Digital
Atten operates connected to controller to control Path Gain.
LNA
Figure 19 Block diagram of Low Noise Amplifier unit for downlink.
This product is a low noise amplifier used for NOTCHCELL downlink. It is generally composed of RF block and
Fault block (Alarm circuit).
RF block has approximately 30dB gain at CDMA1900 through 3-stage amplification, and its noise index is
0.9dB. Fault block is a circuit that detects current flowing in each TR of RF block.
Fault circuit detects current flowing in 1
st
stage TR and 2
nd
& 3
rd
stage TRs. If TR current is less or more than
set value due to the change of LNA environment, it generates TTL signal (5V).
Connection
Port Connected to
RF IN DL on the DPX-MS.
RF OUT RF IN on the PA-DL unit.
CON On the ARCU board
CON On the PSU unit.
Specification
Item Specification Remarks
Frequency 1945MHz ~1950MHz)
Bandwidth 5MHz
Gain
24~49dB
± 0.5dB
Att. : 25dB
Voltage DC 12V
RF connector Type-SMA, female