Table 49: Downstream Rf Signal Output Characteristics; Table 50: Docsis Downstream Channel Rates And Spacing - Juniper G10 CMTS Hardware Manual

Radio Frequency (RF) Specifications
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Table 49: Downstream RF Signal Output Characteristics

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Parameter
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Center Frequency (fc)
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Level
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Symbol Rate (nominal)
64QAM
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256QAM
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• Nominal Channel Spacing
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Frequency response
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64QAM
256QAM
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Total Discrete Spurious Inband (fc ± 3 MHz)
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Inband Spurious and Noise (fc ± 3 MHz)
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Adjacent channel (fc ± 3.0 MHz) to (fc ± 3.75 MHz)
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Adjacent channel (fc ± 3.75 MHz) to (fc ± 9 MHz)
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Next adjacent channel (fc ± 9 MHz) to (fc ± 15 MHz)
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Other channels (47 MHz to 1,000 MHz)
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• Phase Noise
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Output Impedance
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Output Return Loss
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Connector
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1. ±30 kHz includes an allowance of 25 kHz for the largest FCC frequency offset normally built into upconverters.
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Table 50: DOCSIS Downstream Channel Rates and Spacing

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178 JUNOSg 3.0 G10 CMTS Hardware Guide
Nominal Symbol Rate
(Msym/sec)
5.056941 (64QAM)
5.360537 (256QAM)
Value
1
91 to 857 MHz ± 30 kHz
Adjustable over the range 50 to 61 dBmV
5.056941 Msym/sec
5.360537 Msym/sec
6 MHz
~18% Square Root Raised Cosine shaping
~12% Square Root Raised Cosine shaping
< -57dBc
< -48dBc; where channel spurious and noise includes all discrete spurious,
noise, carrier leakage, clock lines, synthesizer products, and other undesired
transmitter products. Noise within +/- 50kHz of the carrier is excluded.
< -58 dBc in 750 kHz
< -62 dBc, in 5.25 MHz, excluding up to 3 spurs, each of which must be
<-60 dBc when measured in a 10 kHz band
Less than the greater of -65 dBc or -12dBmV in 6MHz, excluding up to three
discrete spurs. The total power in the spurs must be < -60dBc when each is
measured with 10 kHz bandwidth.
< -12dBmV in each 6 MHz channel, excluding up to three discrete spurs. The
total power in the spurs must be < -60dBc when each is measured with
10kHz bandwidth.
1 kHz - 10 kHz: -33dBc double sided noise power
10 kHz - 50 kHz: -51dBc double sided noise power
50 kHz - 3 MHz: -51dBc double sided noise power
75 ohms
> 14 dB within an output channel up to 750 MHz;
> 13 dB in an output channel above 750 MHz
F connector per [IPS-SP-406]
Nominal Channel Spacing
(kHz)
6000
6000
Bit Rate (bps)
30,341,646
42,884,296