User's manual g. Shdsl termination Unit Scorpio 1400 lcd




Yüklə 1.3 Mb.
səhifə3/15
tarix16.04.2016
ölçüsü1.3 Mb.
1   2   3   4   5   6   7   8   9   ...   15

2.2SHDSL Interface


  • Meet ITU-T G.991.2 Annex A relative requirements

  • Frame structure comply with section 7.1.1 of ITU-T G.991.2

  • Supports fixed mode operation for symmetric multiple data rates according to different network side /customer side interfaces. The data rate does not include 8 Kbit/s framing overheads.

  • Support Wetting Current function for feeding of a low current(between 1.0 mA and 20 mA)on the pair to mitigate the effect of corrosion of contacts.

  • Support power back off, comply with table 6-2 of ITU-T G.991.2.

  • Data rate of 64K to 2.304M bps (2 wires) or 64k to 4.624M bps (4 wires), (incrementing step: 64K bps).

  • Modulation Method: 16-TCPAM (16 levels Trellis Coded Pulse Amplitude Modulation).

  • The symmetric PSD for data rate of 256, 512, 768, 1536, 2048 and 2304 Kbit/s comply with the PSD masks defined in Annex A of ITU-T G.991.2.

  • Symbol Rate: (Data rate+8000)/3 symbol/sec

  • Load Impedance: 135 ohms ±5%.

  • Physical Connection Type: Standard RJ-45 jack, 135 ohm balanced via 2 wires or 4 wires twisted pair.

  • Port enabled / disabled configurable.

  • Network Side Interface.

2.2.1DS1 Interface


  • Bit Rate: 1,544 Kbit / s  32 ppm.

  • Frame Format: SF (D4), ESF, or ESF+CRC, field selectable.

  • Line Code: AMI or B8ZS, field selectable.

  • Impedance: Normal 100 ohms  5% resistive, symmetrical pair.

  • Power Level: For an all-one transmitted signal, the power in a 3 kHz band centered at 772 kHz is between 12.6 and 17.9 dBm. The power in a 3 KHz band centered at 1544 kHz is at least 29 dB below that at 772 kHz.

  • Jitter performance: Meet ITU-T G.824 requirements.

  • The DS1 network side interface of STU-C provide the function for the cable length (from 0 to 200 meters) compensation

  • Physical Connection Type: Standard RJ-48C / RJ45 jack.

2.2.2E1 Interface


  • Comply with G.703 Standard.

  • Bit Rate: 2,048 Kbit / s  50 ppm.

  • Frame Format: Unstructured or Structured framing, field selectable

  • Line Code: High Density Bipolar of Order 3 (HDB3).

  • Impedance: Normal 120 ohms  5% resistive, symmetrical pair.

  • Jitter performance: Meet ITU-T G.823 requirements.

  • Normal Peak Voltage of a Mark (pulse): 3 V for 120 ohms. Peak Voltage of a Space (no pulse): 0 ± 0.3 V for 120 ohms.

  • Normal Pulse Width: 244 ns.

  • Ratio of the Amplitudes of Positive and Negative Pulse at the Center of Pulse Interval: 0.95 to 1.05.

  • Ratio of the Widths of Positive and Negative Pulse at the Normal Half Amplitude: 0.95 to 1.05.

  • Line Interface: 120 ohm (RJ-45 / RJ48C) balanced, 75 ohm (BNC).

  • Physical Connection Type: Standard RJ-48C/RJ-45 jack (Balance) or BNC (Unbalance).

  • Signal of input port was defined as above and can be modified by the characteristics of the interconnecting pair. The insertion loss of this pair at a frequency of 1024 kHz is in the range of 0 to 6 dB.

  • Minimum Return Loss at the Input Port: 12 dB for 51 to 102 kHz, 18 dB for 102 to 2,048 kHz 14 dB for 2,048 to 3,072 kHz

2.2.3V.35 Interface


  • Electrical Characteristics: Comply with ITU-T V.35 interface.

  • Software configurable for V.35, X.21, RS530, V.36/RS-449.

  • Data Rate: n x 64 Kbit/ s, where n = 1~36(2 wires) or n=2~ 72(4 wires). The data rate does not include 8 Kbit/s framing overheads.

  • Data inversion selectable.

  • Clock inversion selectable (internal/ DTE/ line/ DTE-hybrid).

  • Physical Connection Type: The pin assignment of ITU-T V.35 interface comply with 34-pin ISO 2593 connector.

2.2.4Ethernet Interface (S1400RL)


  • Provide a 10/100 Base-T half/full duplex auto sensing of Ethernet Interface.

  • Comply with the IEEE 802.3/ IEEE 802.3u.

  • Physical Connection Type: Standard RJ-45 connector.

  • Operate as a self-learning bridge specified in the IEEE 802.1d full protocol transparent bridging function

  • Supporting up to 128 MAC learning addresses.

  • Supporting Bridge filter function based on source MAC addresses

2.3Timing and Synchronization


Table 2-1 shows three modes to be field selectable.

Table 2 1 Timing and Synchronization



Mode Number

STU C Symbol Clock Reference

STU R Symbol Clock Reference

Example Application

Mode

1

Local oscillator (internal timing)

Received symbol clock

"Classic" HDSL

Plesiochronous

2

Transmit data clock(DTE timing)

Received symbol clock

Main application is synchronous transport in both directions.

Synchronous

3

Hybrid Transmit data clock (Hybrid DTE timing)

Received symbol clock

Synchronous downstream transport and bit-stuffed upstream is possible.

Hybrid:

downstream is synchronous and

upstream is plesiochronous



  • Provide a 10/100 Base-T half/full duplex auto sensing Ethernet Interface.

  • At all rates, the transmit symbol clock during data mode from any SHDSL device is accurate to within ±32 ppm of the normal frequency.

  • When the STU-C receiver loses Transmit data clock, it will fall back and use a free-running local oscillator in the STU-C,the STU-C local oscillator will have the accuracy of ±32 ppm.

  • The SHDSL transceivers will operate in a master-slave mode with STU-R (Slave) synchronized to the received signal from the STU-C (Master) (i.e. Received symbol clock).

  • If the STU-R receiver loses timing, it will fall back and use a free-running local oscillator in the STU-R,the STU-R local oscillator will have the accuracy of ±32 ppm.

  • The SHDSL system is an equipment of frequency transparency. The average traced frequency deviation at the DS1/E1 output port is less than ±1 x 10-11 to the frequency at the DS1/E1 input port under Mode 2 clocking architecture.
1   2   3   4   5   6   7   8   9   ...   15


Verilənlər bazası müəlliflik hüququ ilə müdafiə olunur ©azrefs.org 2016
rəhbərliyinə müraciət

    Ana səhifə