WNI Global Challenger L Series, Руководство пользователя и инструкция по установке

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1-11 This manual is provided by WNI Global and its confidentiality is preserved. Without the pre-written consent from WNI Global,
anyone may not disclose, extract, cite or publish any part or all parts of this manual. Version No.: V2.0
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Switch/Framing – The Challenger L IDU includes an Ethernet Switch and a proprietary Framer
that are designed to support 1+1 protection switching, ring architecture routing, and overall
network control functions.
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Network Processor – The
Challenger L IDU
includes a Network Processor which performs SNMP
and Network Management functions.
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Modem/IF – The Challenger L IDU Modem performs forward-error-correction (FEC)encoding,
PSK/QAM modulation and demodulation, equalization, and FEC decoding functions. The IF chain
provides a 350 MHz carrier and receives 140 or 60 MHz carriers. The multiplexer function is built
into an appliqué that resides in the Modem/IF Module. Two modems can be used for 1+1
protection or ring architectures.
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Power Supply – The Challenger L IDU power supply accepts - 48 Vdc and supplies the
Challenger L IDU and ODU with power. A second redundant power supply may be added as an
optional module.
The Modem Processor and its associated RAM, ROM, and peripherals control the digital and analog
Modem operation. It also provides configuration and control for both the IF and I/O cards.
The
Challenger L IDU interfaces with the Challenger L ODU to receive and provide modulated
transmit and receive waveforms.
The 256-QAM Modem performs the modulation and demodulation of the payload/wayside/SNMP
data and forward error correction using advanced modulation and coding techniques. Using all-
digital processing, the 256-QAM Modem uses robust modulation and forward error correction
coding to minimize the number of bit errors and optimize the radio and network performance.
The 256-QAM Modem also scrambles, descrambles and interleaves/deinterleaves the data
stream in accordance with Intelsat standards to ensure modulation efficiency and resilience to
sustained burst errors. The modulation will vary by application, data rate, and frequency
spectrum. The highest order modulation mode supported is 256 Quadrature Amplitude
Modulation (QAM). Table 1-3 summarizes the TCM/convolutional code rates for each modulation
type supported by the Digital Radio.