Tektronix MTM400A, Техническое описание

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Specifications
1- 6
MTM400A Specifications and Performance Verification
Table 1- 11: QAM Annex B2 measurements
Characteristic Description
RF Lock RF lock is indicated by LED and Status
Input Level (Signal Strength) (Typical) Range: --64 dBm to --19 dBm (45 dBuV to 90 dBuV relative to 75
Ω
s)
Resolution: 1 dB
Accuracy:
3 dB
EVM (Error Vector Magnitude) (Typical) Display Range for 64 QAM:
≤
1% to
≥
5% rms
Display Range for 256 QAM:
≤
1% to
≥
2.5% rms
Resolution: 0.1%
Accuracy:
1%
MER (Modulation Error Ratio) with Equalizer
(Typical) Display Range:
64 QAM: 22 dB to 37 dB
256 QAM: 28 dB to 37 dB
Resolution: 0.1 dB
Accuracy:
1 dB for MER < 25 dB; 3 db for MER 25 dB to 34 dB
(measured at --30 dBm input)
SNR (Signal to Noise Ratio) (Typical) Display Range:
64QAM: 22 dB to 37 dB
256QAM: 28 dB to 37 dB
Resolution: 1 dB
Accuracy:
1 dB for SNR < 25 dB; 3 db for SNR 25 dB to 34 dB
BER (Bit Error Ratio) Pre-RS BER is displayed
TEF (Transport Error Flag) Transport Error Flags (uncorrectable error count) in a 1 second window and 10
second window are displayed.
Constellation The RF constellation is displayed.
Table 1- 12: QAM Annex C interface card characteristics
Characteristic Description
Input Frequency Range 88 MHz to 858 MHz, 62.5 kHz steps
Modulation Format 16 QAM, 64 QAM, 256 QAM (compliant with ITU J-83 Annex C)
Modulation Baud Rate, QAM C 4.5 Mbaud/s min; 5.5 Mbaud/s max
Input Signal Level --57 dBm (50 dBuV) to --27 dBm(80 dBuV), with a 16, 64, and 256 QAM input,
providing five or fewer Transport Error Flags in 12 seconds, which corresponds to
a post FEC rate of 1e
--8
Modulation Error Ratio (with equalizer) 38 dB typical, with a 64 QAM input
Receiver Bandwidth, QAM C 6 MHz nominal
Input Termination Impedance 75
Ω
nominal
Input Return Loss 6 dB min, 10 dB typical, 88 MHz to 858 MHz