Tainet DT-2000 Series, Руководство пользователя

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INTRODUCTION 1-1
CHAPTER 1: INTRODUCTION
1.1 General Description
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The TAINET DT-2000 series are High-bit-rate Digital Subscriber Line (HDSL)
systems which deliver 2.048Mbps E1 service to the customer up to 4.5 Km (2.8 miles)
length over four 24 AWG (0.5 mm) lines.
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DT-2000 series, use 2B1Q modulation and support Wetting Current, Power Feeding
fully complies with the ETSI standard ETR 152 provide full and fractional E1, switched
E1 or Nx64K E1 service over two pairs of wires.
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Switched E1 or N
×
64K E1 service which is used in Point-to-Point, add-drop
applications such as dial-up video conference, distant learning, and home entertainment,
it also delivers new service such as Switched Multi-Megabit Data Services (SMDS) and
frame relay with speed and economy.
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The 2B1Q line code is a four-level pulse-amplitude modulation code as shown as Table
1-1. Its power average on a sequence of symbols consist with a frame word in all other
positions is between 13.0 dBm and 14.0 dBm, which over the frequency band from 0
Hz to 1168KHz into a 135 ohms termination.
Binary Digits Quaternary Symbol
First Bit (Sign) Second Bit (Magnitude)
1 0 +3
1 1 +1
0 1 -1
0 0 -3
Table 1-1 The 2B1Q Line Coding
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The HDSL system consist of Line Termination Unit(LTU) for Central Office (CO) in the
network side, and Network Termination Unit (NTU) for Remote Terminal (RT) in the
user side. It will provide an alternation to repeat E1 lines for buyer to support
repeaterless 2048Kbps rate access over non-loading copper loop.
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Support either 120 ohms balanced (terminal block) or 75 ohms unbalanced (BNC).
Fractional E1 use one or two loops for data transmission from 64Kbps to 2048Kbps
(N x 64K) of V.35, RS-530, V.36(RS-449) or X.21/V.11 interfaces.
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Rack mounted model may apply 16 cards to one shelf. TAINET Network Management
System work over TCP/IP for Windows 9x/NT platform is available.
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Remote configuration will be matched with central site: for general application, users just
need to setup CO and RT to be connected. Once it is connected, the parameters of RT
will follow CO automatically. For example, when CO site setup from Full E1 to
Fractional E1, the RT site will follow up to Fractional E1 too.