Have you ever experienced the splash screen, black or blue screen or lagging frame when using HD-SDI (High definition Serial Digital Interface) fiber converter at the 3Gbps data rate? If so, today’s contents about 3G-SDI video SFP (small form-factor pluggable) module may be very useful for you to escape this predicament.
With the wide deployment of fiber optics, the HD (high definition) video transmission over fiber is no longer a dream. We are familiar with the HD video interface such as HDMI (High Definition Multimedia Interface), HD-SDI, HD-CVI (High Definition Composite Video Interface) and so on. But what is 3G-SDI?
3G-SDI is an updated version of HD-SDI which can offer nominal data rates of 1.485 Gbit/s (dual link) and 2.970 Gbit/s serial link, respectively. 3G-SDI system can support the digital video signals with SMPTE424M, SMPTE292M, SMPTE259M, SMPTE297M , SMPTE305M and SMPTE310M standards, as well as the DVB-ASI (EN50083-9) format digital video signals. Similar with HD-SDI, 3G-SDI is generally used for the television broadcasting. But as the technology advances, it is now widely applied in global security applications such as high-end surveillance or unmanned systems, allowing simple designs or upgrades with full HD cameras.
|SDI Transmission Method|
|Specification||SMPTE 259M||SMPTE 292M||SMPTE 424M|
|Transmitted Data Quantity||306 Mbps||1.485 Gbps||2.970 Gbps|
|Transmission Frequency||180 MHz||About 750 MHz||About 1.5 GHz|
|Maximum Resolution||960×firstname.lastname@example.org||1080i60, 1080p30||1080p60|
A variety of 3G-SDI video products have been launched in the market. These equipment include 3G-SDI extenders, 3G-SDI distribution amplifiers, 3G-SDI matrix switchers and so on. They are adopted with 3G pathological signal but can also be compatible with 1.5G pathological signal for long-distance transmission, meeting the diversified demands of users.
However, though there are many 3G-SDI equipment in the market, most of the products cannot pass the SDI pathological-code test. In this case, if the video signals are transmitted in an irregular bitrate, the issues that are mentioned in the beginning of the article may occur. This phenomenon will happen especially under the operation of 3Gbps (i.e., 1080p application) rather than 1.5G (720p or 1080i application). Why? Excluding the factors of equipment quality and brand differences, the cost factor may be the main reason. In the current market, most of the HD-SDI converters employ the ordinary SFP optics, namely the 1.25G or 2.5G digital SFP to replace the specific video SFP. Inevitably, the error rate increases when transmission bit rate is irregular. Since the application field of HD-SDI converter requires higher quality frames, it is very necessary to use the specific 3G-SDI video SFP to avoid these problems and ensure the high definition and smooth frames of the video.
3G-SDI module is designed in SFP package which is compliant with SFP Multi-Source Agreement (MSA) and SFF-8472. 3G-SDI module can be designed with different form factor such as dual or single transmitter, dual or single receiver, duplex or BiDi (bi-directional) transceiver (transceiver & receiver). According to the operation wavelengths, 3G-SDI module can be used in multimode or single-mode application—works on 850nm wavelength to support up to 300m transmission distance over multimode fiber and 1310 or 1550nm wavelengths to support 10km or 80km transmission distance over single-mode fiber. In addition, 3G-SID CWDM SFP modules are also available in the market. Furthermore, 3G-SDI SFP module also support DDM (Digital Diagnostic functions) function to monitor extensive output optical power, bias current, supply voltage and operating temperature etc.
Similar to the ordinary SFP module that is used in the switch to transmit and receive the signals, 3G-SDI SFP module is for the same purpose but used in the HD-SDI equipment. It plays an important role in the application of digital video extension over fiber. Three classical 3G-SDI SFP application cases (over SMF) are shown in the following:
Case 1: Using a 3G-SDI SFP transmitter for transmitting the signals and a 3G-SDI SFP receiver for receiving the signals over a simplex SMF. This is the most basic case of the HD-SDI video transmission.
Case 2: Using 3G-SDI SFP transceivers which can both transmit and receive over a duplex LC SMF.
Case 3: Using a pairs of 3G-SDI BiDi SFP transceiver which can both transmit and receive over a simplex LC SMF. This solution can help save more cost on fiber.
FS.COM offers a full line of the 3G-SDI SFP modules that are mentioned above. By making continuous improvements, more and more related products will be launched in the near future. In addition, for high-definition video transmission, we also offer the high-quality SDI/HDMI/VGA fiber converters, as well as other optical multiplexers. Welcome to contact us for more details (E-mail: email@example.com).