QAM Modulator
Outline
In the broadcasting process of digital TV programs, QAM modulator mainly complete QAM modulate and up-frequency conversation process for TS stream, Apply to multi-level transmission, broadcasting of digital TV business.
QAM modulator mainly used in head end of digital TV broadcasting, it is composed by two modules QAM modulator and digital up-frequency conversation, modulate the input serial or parallel TS stream via the QAM modulator module, modulate to IF frequency, then pass the up-frequency conversation module to frequency transform, into standard channel or supplement channel which meet demand. Finally mixed enter into CATV network, and received by the terminal STB.
Features
* Support IYU-T. 83A
* Error correct encode completely meet DVB-C standard
* Be workable under QPSK, 16QAM, 32QAM, 64QAM, 128QAM, 256QAM mode
* Input interface: ASI and SPI (DS3/E3 optional)
* Input date bit rate range: 1.5~51.6Mbps
* Output data bit rate range: 2~56Mbps
* Output signal Bandwidth(BW) range: 1.15~8.05MHz(roll down coefficient is 0.15)
* Output data symbol rate range: 1~7Mbaud/s
* RF frequency range: 110~862MHz
* Output level range: 95dBuV~115dBuV (stepping -0.5dB/step adjustable )
* 188/204 packet length adaptable itself
* Adopt big enough cache design, ASI interface support paroxysmal and symmetrical input TS stream, and can equilibrate and reforming the TS stream, enhance the efficiency of output TS stream.
* Input data empty packet filtering and output data fill in.
* PRC proofread function, can accurately correct several PCR of input data separately.
* Real time inspect and display for the efficient TS stream.
* Adaptable itself to filtering circuit design to ensure the excellent suppress capability out of band.
* -20dB RF test mouth to monitor IF output.
* Fault alarm display
* LCD screen display
* Network control interface, make centralize management, remote upgrade and maintenance (network management software only for option)
* Power-off memory
Specifications
| Input interface |
ASI and SPI (DS3/E3 optional) |
| Input date bit rate range |
1.5~51.6Mbps |
| Output data bit rate range |
2~56Mbps |
| Output signal Bandwidth(BW) range |
1.15~8.05MHz(roll down coefficient is 0.15) |
| Output data symbol rate range |
1~7Mbaud/s |
| RF frequency range |
110~862MHz |
| Output level range |
95dBuV~115dBuV (stepping -0.5dB/step adjustable ) |
| ASI interface (Asynchronous Serial Interface) |
Input |
Socket: BNC |
| Impedance: 75Ω |
| Packet format: 188 or 204 byte(no route encode) |
| Route data speed velocity: 270Mbps |
| Max efficient data: 51.6Mbps |
| Standard: meet DVB standard, support paroxysmal and symmetrical input TS stream |
| Ring route output |
Socket: BNC |
| Impedance: 75Ω |
| SPI Input Interface (Synchronous Parallel Interface) |
Socket |
DB-25 female |
| Packet format |
188 or 204 byte(no route encode) |
| Standard |
compatible of DVB, LVDS working methods |
| IF Interface |
IF output |
Linker: BNC socket |
| Impedance: 75Ω |
| Center frequency: 35.000~44.000MHz adjustable (stepping 125KHz) |
| IF bandwidth: ≤ 8MHz |
| Return loss: ≥ 18dB |
| Input level: 100dBuV |
| RF Interface |
RF output |
Connector: F jack (the metric system) |
| Impedance: 75Ω |
| Output frequency: 110MHz~862MHz (provide per model) |
| Return loss: ≥ 12dB |
| Output level: Max 115dBuV(adjustable, stepping at 0.5dB) |
| Level adjustable range: 0~20dB |
| Carrier suppression: > 55dB |
| Modulate error rate(MER): ≥ 32dB(closing balance), ≥ 45dB(opening balance) |
| Bit modulate error rate(BER): ≤ 1*10-8 |
| SNR(Outside band): ≥ 50dB |
| RF test output |
Connector: BNC |
| Impedance: 75Ω |
| Output level: 75dBuV~95dBuV (adjustable) |
| Signal channel coding |
Modulate mode |
16QAM, 32QAM, 64QAM, 128QAM, 256QAM |
| Channel coding |
comply with DVB standard RS coding |
| IF modulate error rate(MER) |
≥ 44dB |
| SNR(outside band) |
≥ 50dB |
| Network administration interface |
Ethernet interface |
Ethernet IEEE802.3, RJ45interface |
| Software agreement |
the SNMP agreement |
Power supply
|
Voltage |
110~220VAC |
| Frequency |
50/60Hz± 2% |
| Electric Power |
20W |
| Working environment |
Surrounding temperature |
+5° C~45° C |
| |
Storage temperature |
-25° C~+55° C |
| |
Relative humidity |
10~75% |
| Radiate and safety requirements |
Comply with GB13837-92 and GB8898-88 standard |
| Dimension |
44.5mm(height, 1U)× 483mm(width, 19″ ) × 330mm(deep) |
| Weight |
3.5 kg |
