Wireless broadcast systems DVB-T/H 5000 Modulator
OVERVIEW
Designed to meet the most demanding requirements of today’s Digital Terrestrial Television Broadcast Market,
the DVB-T 4000 from UBS is ranked number one in its class. A key factor in the products success is the quality
of the CODing and modulation process. The modular design makes the unit highly flexible and the modulator is
easily adaptable to provide the exact features required in a specific application. This means that you will only
have to pay for the functional features that you need. Retronfitting of features is easy by uploading new
firmware and software from a standard PC.
APPLICATON
The performance and flexIbility of the DVB-T 4000 allows it to excel in any application related to DVB-T
modulation. Being a DVB_T modulator the core function of the DVB-T 4000 is to modulate on MPEG-2
transportstream (input) onto a DVB-T compliant COFDM spectrum (output) in accordance with the rules
for channel coding and modulation specified in the DVB-T standard ETSI EN 300 744.
BASIC VERSION
The basic version of the DVB-T 4000 delivers the COFDM spectrum on a user defined frequency between 35
and 37 MHz, Inverted/non-inverted spectrum is selected on the front panel. The spectrum bandwidth may be
user configured of 8 or 7 MHz as required. This flexibililty will allow the user to interface the IF signal to a
wide range of transmitters and frequency converters.
The basic unit has two MPEG-2 inputs (ASI format). Switching between the two inputs can be done manually
and automatically. The latter option provides near seamless switching to a secondary transport stream incase
the primary transport stream source fails (a truly valuable feature for broadcast applications.) The user can
configure the basic version to any transmission mode listed in ETSI EN 300 744 (excluding hierarchical mode
and SFN mode.)
Specifications
Signal processing
1. Supported modes
2. IFFT: 2K 8K
3. Guard intervals: 1/4, 1/8, 1/166, 1/32
4. Code rates: 1/2, 2/3, 3/4, 5/6, 7/8
5. Constellations: QPSK, 16-QAM, 64-QAM
6. Hierarchical modes option: 16-QAM and 64-QAM in alpha-1, alpha-2 and alpha-4
7. Network mode: MFN
8. Network mode: SFN and MFN
9. Bandwith: 8MHz and 7 MHz
10. Bandwith: 8MHz 7 MHz and 6MHz
Electrical specifications
1. Inputs
2. MPEG-2: Two ASI inputs, BNC 75ohm
3. Clock reference (carrier frequency and SFN timing):
4. Connector: BNC
5. Frequency: 10MHz
6. Level: 100mV—3Vpp
7. Impedance: 50ohm/>1kohm,user selectable
8. Time reference (SFN timing):
9. Connector: BNC
10. Frequency: 1PPS
11. Level: 0-5V
12. Trigger: Positive transition
13. Impedance: 50ohm/>1kohm,user selectable
Output (standard version)
1. IF output:
2. Connector: BNC 50ohm
3. Centre frequency: Adjustable 35-37MHz in steps of 1Hz
4. Frequency stability: Intern ref 1ppm / or in accordance with extern ref accuracy
5. Spectrum polarity: Inverted and non-inverted selectable via front panel menu
6. Level: from 8dBm/2dBm step 0.1dB
7. Stability: ±0.2dB
8. Return loss:>26dB
9. Spectrum outside band
10. +/-3.8MHz: 0dB +/-4.25MHz: <48dB +/-5.25MHz: <56dB
11. Harmonics and spurious:<60 dB relative to the total out-put power
12. MER: designed to meet 45 dB
Power supply
1. Voltage: 90-132VAC/180-250VAC
2. Frequency:47-63Hz
3. Consumption: MAX 25VA
Test modes
1. Removal of one carrier: Moveable one-carrier hole for noise test
2. Removal of 50 carriers: Move-able 50-carrier hole for test of 1M and quantisation noise
3. Single carrier: COFDM spectrum replaced by a single carrier of center frequency. The level of the single carrier
is equivalent to average RMS level of normal COFMD spectrum. The signal is intended for level alignment.
4. TS-Stuffing: PRBS sequence in accordance with ETR290 paragraph9.16.1
Pre-correction
1. The pre-corrector option supports non-linear pre-correction (gain and phases vs. power level)
2. Linear pre-correction (level and group delay response vs. frequency).The pre-corrector allows
3. Further control of the peak power clip level (range +17 dB to +7dB peak power relative to overage RMS level).
4. Non-linear correction:
5. Curve formats: S21 and VO/VI
6. Amplitude scale: Linear and logarithmic
7. Correction points: MAX 256,user-defined position
8. Gain correction: MAX 12 dB, subject to available headroom
9. Phase correction: -6 to + 30 degrees, subject to available headroom
10. Linear correction:
11. Correction points:21
12. Point sPACing: 1/20 of nominal spectrum BW
13. Amplitude correction: ±10dB
14. Amplitude resolution:0.01 dB
15. Group delay correction: ±1000ns
16. Group delay resolution:1ns
Control interface
1. The basic version of the DVB-T 4000 can be operated via the front panel (LCD display and cursor/execute keys)
and via RS232/RS485.Independet (RS232/RS485) interfaces are available in the basic version of the DVB-T 4000.
2. A connector is provided for signaling user programmable alarm events and for muting and resettling via external
switches.
3. RS232 interface: connector 9-pin SUB-D Male, command protocol: SCPI based
4. RS485 Console&CL1: connector 9-pin SUB-D Male, command protocol: SCPI based
5. Alarm interface: connector 9-pin SUB-D Female, output: Two user programmable alarms via separate floating
relays, common make-break contacts, contact rating 60V/0.2A (5W MAX) , Input: Separate Reset control and
Output muting control, activated by ground closure.
6. Ethernet interface: Connector RJ-45, Function: Web browser remote control or SNMP
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