COFDM to QAM transmodulator

GQ-3681 COFDM to QAM transmodulator is headend and repeat equipment with the professional broadcasting quality according to DVB standard. Its main function is decoding signals modulated by COFDM up to DVB-T to TS stream and then modulating digital TV signal up to QAM standard transmitted via HFC or MMDS. The modulator converts input data streams up to DVB-T standard into Radio Frequency (RF) signals. It could extend ground broadcasting transport network and converter interface in the headend. It not only transmit digital signals effectively, but also sends other value-added services to thousands of families. GQ-3681 has the function of remote supervision and control.

Features:

• 
  
          ASI processing units converter input signals to parallel TS, then send data processing units (apply to GQ-3682 only).
  
  


• 
  
          COFDM processing units tune and COFDM demodulate input RF signal ,then send to data processing units when converted to parallel TS
  
  


• 
  
          Data processing units convert input signals from various interface to standard signals and process data in order to carry out QAM modulate pretreatment.
  
  


• 
  
          QAM modulation units modulate data stream to spectrum signals and output to 35.56/36/36.15/44MHz IF signals.
  
  


• 
  
          Keyboard input decided by CPU/LCD/LED/keyboard units. LEDs function is displaying and aptitude controlling.
  
  


• 
  
          Features: (apply to GQ-3682 QAM modulator only about parameter of ASI interface and correlative devices).
  
  


• 
  
          Two Channels input interface( ASI and COFDM), with ASI and COFDM loop output.
  
  


• 
  
          -20dB RF testing interface with IF output
  
  


• 
  
          IF and RF output optional
  
  


• 
  
          ASI input data bit rate:216Mbps(max, per channel)
  
  


• 
  
          Remultiplex 2 channels TS
  
  


• 
  
          PID filtering and reset, users add and delete programs at will, auto-mapping PID of program selected. Support user-defined PID and input bypass.
  
  


• 
  
          Support ITU-T J.83A and B
  
  


• 
  
          FEC up to DVB-C
  
  


• 
  
          Work in mode 16QAM, 32QAM, 64QAM, 128QAM, 256QAM
  
  


• 
  
          Input interfaceASIRFCOFDM tuner
  
  


• 
  
          Input RFCOFDM frequency 170MHz-860MHz
  
  


• 
  
          Input RF BW 6MHz, 7MHz, 8MHz
  
  


• 
  
          Inside-feedback electricityRF input supply DC+9V or DC+12V
  
  


• 
  
          Input data(ASI interface) bit rate:1.55-1.6Mbps
  
  


• 
  
          Output data bit rate:256Mbps
  
  


• 
  
          Output signals BW1.158.05MHz(the Fall is 0.15)
  
  


• 
  
          Output data symbol ratio17Mbaud/s
  
  


• 
  
          Output RF frequency 48-860MHz
  
  


• 
  
          Output level 100dBuV-115dBuV(stepping available)
  
  


• 
  
          188 and 204 packet auto-identify, displaying input data format real time.
  
  


• 
  
          Large cache, ASI interface support input burst and average bit stream, reforming bit stream average in order to promote the output bit stream efficiency.
  
  


• 
  
          NIT mapping and sending, support 44 NIT mapping
  
  


• 
  
          PID filtering and re-mapping
  
  


• 
  
          Various PSI/SI information tables pick-up, parse and modification (customization available).
  
  


• 
  
          SI information replacement and insertion
  
  


• 
  
          Input data null packet filtering and output data stuffing
  
  


• 
  
          PCR correction function can correct various input data, respectively and accurately
  
  


• 
  
          Show and inspect system input bit rate and valid bit rate real-time
  
  


• 
  
          -20dB RF testing interface with IF output
  
  


• 
  
          Outstanding self-adapting filtering circuit designs to maximal reliability and availability.
  
  


• 
  
          Error alarming
  
  


• 
  
          LCD display
  
  


• 
  
          Network interface introduces remote maintenance, supervision and software upgrade
  
  


• 
  
          Power off memory
  
  


• 
  
          Network interface introduces remote maintenance, supervision and software upgrade