Tektronix MTM400A, Техническое описание

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Specifications
MTM400A Specifications and Performance Verification
1- 11
Table 1- 19: COFDM measurements
Characteristic Description
Overall Receiver Lock Status Overall receiver lock status is indicated by an LED on the rear panel.
Transmission Coding Parameters The receiver reports the current status of the following transmission parameters:
-- QPSK/16, QAM/64, QAM encoding
-- 2K/8K Transmission mode
-- Hierarchy status (hierarchy on/off, alpha value)
-- Viterbi puncture rate
-- Guard Interval Value
-- Gross bit rate in the channel
-- Spectrum polarity (inverted/non inverted)
Input Level (Signal Strength) (Typical) Ranges, High Sensitivity mode:
QPSK (4QAM): --85 dBm to --10 dBm (24 dBuV to 99 dBuV)
16QAM: --80 dBm to --10 dBm (29 dBuV to 99 dBuV)
64QAM: --72 dBm to --13 dBm (37 dBuV to 96 dBuV)
Ranges, High Resolution mode:
QPSK (4QAM): --45 dBm to --10 dBm (64 dBuV to 99 dBuV)
16QAM: --45 dBm to --10 dBm (64 dBuV to 99 dBuV)
64QAM: --45 dBm to --13 dBm (64 dBuV to 96 dBuV)
Resolution: 1 dBm
Accuracy:
3 dBm
RF Carrier Offset Accuracy: 50 ppm, of the tuned frequency; typical
Carrier Power Distribution The carrier-by-carrier signal-to-noise power ratio is displayed.
Channel Flatness in dB can be viewed from spectrum display.
Tilt in dB can be viewed from spectrum display.
SNR (Signal to Noise Ratio) (Typical) Display Range:
6 dB to 40 dB for QPSK (4QAM):
11 dB to 40 dB for 16QAM
16 dB to 40 dB for 64QAM
Resolution: 1 dB
Accuracy: 1 dB to 30 dB SNR (measured at --30 dBm input in high resolution
mode)
EVM (Error Vector Magnitude) (Typical) Display Range:
≤
1% to
≥
30% rms, for QPSK
≤
1% to
≥
20% rms, 16QAM
≤
1% to
≥
8.5% rms, 64QAM
Resolution: 0.1%
Accuracy: 1% (1 EVM unit), and additional 20% of reading