NEC PASOLINK+, Руководство пользователя

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MTD-PL-028/141005 PASOLINK
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155 MB 1+0/1+1 SYSTEM
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2. FEATURES
2.1 Advanced Technologies and Superb Performance
Throughout the SDH radio system, NEC’s own advanced technologies are used. Intensive
use of Microwave Integrated Circuits (MIC’s) and Hybrid IC’s (HIC’s) make the TRP durable
and compact. Also, custom made large-scale integrated circuits (LSI’s) are applied. For
example, a new digital MODEM is incorporated in a single LSI chip, specially developed by
NEC for the radio equipment. Furthermore, low-power high-speed complementary metal
oxide semiconductor (CMOS) LSI’s are extensively used, making the equipment more
compact and reducing the power consumption.
2.2 High System Gain
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Multi-Level Coding Modulation (MLCM) is applied to ensure a better error performance (32
QAM System).
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Forward Error Correction (FEC) with Reed-Solomon coding is equipped to improve BER
performance.
2.3 Easy and Quick Installation
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Interconnection: Only one coaxial cable and automatic equalization (up to 450 m by using
12D-FB cable)
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Compact and Light
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Various mounting methods for IDU, ODU, and antenna
2.4 Common platform architecture
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The ODU of 128 QAM type can be used for 32 QAM type.
2.5 Frequency Agility and Easy Tuning
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Field tunable local-oscillator (Synthesizer)
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RF point frequency can be changed through LCT (Local Craft Terminal, except 6 – 8 GHz)
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Frequency Tunable without changing RF FIL on Subband basis.
2.6 TX Power Control
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ATPC (Automatic Transmitter Power Control) reduces interference to neighboring
systems, improves residual BER performance, alleviates upfade problems. The adjustable
range of ATPC is -20 dB to 0 dB (128-QAM) and –23 dB to 0 dB (32-QAM).
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MTPC (Manual Transmitter Power Control) is also available through LCT. The adjustable
range of MTPC is –20 dB to 0 dB (128-QAM) and –23 dB to 0 dB (32-QAM) at 1 dB step.
2.7 System Flexibility
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(1 + 0) Unprotected
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(1 + 1) Hot-standby
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(1 + 1) Hot-standby with Space Diversity
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(1 + 1) Twin-path (Hitless switching)
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IDU is commonly used for all frequency bands.
(In case of 1+1 Hot-standby or twin-path system, either one antenna system with hybrid
combiner or two antenna system excluding hybrid combiner is chosen. Please refer to Fig. 3
(a), (b).)
1 + 1 Hybrid combiner: NEC provides 3 dB balance-type hybrid combiner.