CT3155B Directly Modulated Optical Transmitter is specially designed for Overlay slot system. It has the ability of supporting up to 32 IPQAM frequency point spots. As the first company to introduce Overlay frequency point spot system, C-Data optimizes performance and structure of spot transmitter by large number of project experience and system debugging experience, focusing application of spot system. And finally, we greatly increase performance of spot system.
Unique electric-control optical attenuation function guarantees optical difference of spot system can be automatically controlled as it is set by automatically controlling spot optical signal based on broadcast signal value after setting optical difference of spot system. This function can realize automatic adjustment in the whole course of spot system. So this design is humanized and easy to operate.
Meanwhile, special AGC circuit with electric-control attenuator as core can realize automatic control of modulation and flexible control of drive level value. And it can guarantee stability of electrical level after system debugging, and greatly simplify project debugging.
Optimized integrated design of pre-distortion, amplifier and laser
Integrated electrical control of Overlay spot function, can be spot debugging set by LDC or NM control
Innovative operation function of AGC and MGC, working separately at the same time, make the product easy to use and improves the applicability of the system.
AGC has a function which can be set to “ON” or “OFF”.
Spot machine with Overlay has the function of automatic shutting down spot when main line power is low.
New-type and stable laser bias and temperature control
ITU wavelength DFB laser
Bandwidth can be up to 1GHz
By adopting low-consumption design, complete machine power consumption < 10W, reliability of equipment is greatly increased.
Double-power, hot-plug, balance load operation, light power load, seamless switching when it fails, greatly increase life time.
By equipped SNMP network management function, it has the function of remote network management and local monitoring.
LCD operation status: optical power, bias current, laser temperature, refrigeration current and spot setting status, etc.
Optical Performance Index
Optical Wavelength Range
1550±20 or ITU wavelength
DFB Laser Output Optical Power
Optical Return Loss
Laser DFB RIN
Main Broadcasting Input Optical Power
Main & Side Optical Power Difference Setting Range
0 ~ 8
Main Input Low-limit Setting Range
+5 ~ -5
Shut down laser when main is lower than this value
Electrical Performance Index
AM ~ VSB
47 ~ 1000
Flatness of Frequency Response
RF Drive Level
MGC Modulation Level
MGC Modulation Step Length
Input Return Loss
Broadcasting Digital Index2
Spot Analog Transmission3
Spot Digital Transmission4
AC 220V Supply
DC -36~ -75V
DC -48V Supply
0~90% No Condensation
0~95% No Condensation
59 PAL-D (47~550MHz) analog carrier transmitter, OMI=3%, 10KM fiber, 1-10 km test, 0dBm receive
59 QAM (47~550MHz) analog carrier transmitter, OMI=3%, 10KM fiber, 1-10 km test, 0dBm receive
Target on broadband overlay , 8 PAL-D(47~550MHz) analog carriers load transmitter, OMI=12%( same as broadcast OMI is 3%, Overlay power is 6dB lower than broadcast), 10KM fiber, -6dBm receive
Target on broadband overlay, 32 QAM( 550~1000MHz) digital carriers load transmitter, OMI=12% ( Broadcast keeps 6 analog, the digital channels OMI is 3% , overlay power is 6dB lower than broadcast), 10KM fiber, -6dBm receive, target on narrowband overlay, 16 QAM(550~1000MHz) can be loaded.
1550nm Directly Modulated Optical Transmitter
SNMP network management, 1550nm optical wavelength range , Optical power 10mW, Broadcast mode, SC/APC interface, double powers 220V/AC,suitable for 25 km range transmission