ViaSat VBM-1400, Инструкция по установке и эксплуатации

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VBM-1400 Broadband Modulator Installation and User’s Guide
General Description
1018360 Rev. 002
1-2
1.3 VBM-1400 Specifications
The specifications for the VBM-1400 are listed in Table 1-2.
Table 1-2 VBM-1400 Specifications
Item Specification
Modulator Specifications -----------------------
AMM -----------------------
Symbol Rates 5-30 Msym/sec in 1sym/sec increments
Spectral Shaping 20%, 25%, 35% SRRC, programmable
Modulation & Code Rates QPSK: 1/2, 2/3, 3/4, 5/6, 7/8
8PSK: 2/3, 3/4, 4/5, 5/6, 8/9
FEC Reed-Solomon/Turbo per Broadcom
DVB -----------------------
Symbol Rates 5-30 Msym/sec in 1sym/sec increments
Spectral Shaping 20%, 25%, & 35% excess bandwidth, programmable.
Modulation & Code Rates QPSK per ETSI 300 421: 1/2, 2/3, 3/4, 5/6, 7/8
FEC Per ETSI 300 421: Reed-Solomon/Viterbi
Scrambling / Interleaving Custom
Radio Frequency Specifications Optional RF output from either a 70/140MHz daughter board or an L-
band daughter board. Both the main RF output and the monitor
output connectors are 50 ohm BNC.
----------------------- 70/140 Output L-band Output
Transmit frequency 50 – 180 MHz 950 – 1450 MHz
Frequency step size 100 Hz 100 Hz
Frequency accuracy ± 5 PPM or external reference ± 5 PPM or external reference
Transmit power level 0 to –25 dBm -5 to –30 dBm
Monitor Output The Monitor output must be 20 to
30dB lower than the main RF
output at all frequencies. The Monitor output must be 20 to
30dB lower than the main RF
output at all frequencies.
Power output accuracy ± 1 dB at 25 C ± 1 dB at 25
o
C over 500MHz
Power output stability ± 0.5 dB ± 0.5 dB
Power output steps 0.1 dB 0.1 dB
Spurious -50 dBc in any 4 KHz band -50 dBc in any 4 KHz band.
Harmonics -40 dBc -40 dBc
Quadrature <2 degrees <2 degrees
Carrier rejection -30 dBc -30 dBc
I/Q Balance <0.2 dB <0.2 dB
Phase noise 100 Hz
1 kHz
10 kHz
100 kHz -57 dBc/Hz
-70 dBc/Hz
-80 dBc/Hz
-90 dBc/Hz 100 Hz
1 kHz
10 kHz
100 kHz -57 dBc/Hz
-70 dBc/Hz
-80 dBc/Hz
-90 dBc/Hz
Return loss >12 dB into 50 ohms >12 dB into 50 ohms
Internal Reference 10 MHz square wave ± 5 PPM
External Reference In 1-25 MHz sine or square wave, 50% duty cycle, adjustable in 8 kHz
steps, 0 to -20 dBm amplitude
Reference Out The output reference can be enabled/disabled via the front panel or
control interface. The output is selectable between the external input
reference feed back, or the internal 10MHz reference at -5 to 0 dBm.