With the popularization of optic fiber communication, the adoption of optic fiber for high-definition video transmission has been the reality. Furthermore, there appear various video optical terminal devices in the market. The commonly-seen types include HDMI(High Definition Multimedia Interface), HD-SDI(High Definition – Serial Digital Interface), HD-CVI(High Definition Composite Video Interface), etc. Then about 3G-SDI, how much do you know about it? And what is the difference between 3G-SDI video devices and 3G-SDI video SFP optical transceiver?
What Is 3G-SDI?
3G-SDI is an upgraded version of HD-SDI with a rate of 1.485G(also regarded as 1.5G, corresponding to SMPTE-292M standard, supporting 720P) and 2.97G (also regarded as 3G, corresponding to SMPTE-424M standard, supporting full HD 1080P/60HZ). 3G-SDI supports the transmission of serial digital video signals and DVB-ASI (EN50083-9) digital video signals that are confirmed to the standards of SMPTE-424M 3Gbps HD-SDI, SMPTE-292M HD-SDI or SMPTE-259M SDI. Similar to HD-SDI, 3G-SDI is also used in the television studio. With the upgrading of technology, it is also widely used in global security applications such as high-end surveillance and unattended operation systems.
3G-SDI Video Devices vs. 3G-SDI Video SFP Optics: What Is the Difference?
Currently, it is full of various 3G-SDI video products in the market, including 3G-SDI optical terminal device, 3G-SDI distribution amplifier. These products can support the long-distance transmission of the irregular bit rate signal of 3G and 1.5G, and meet the various needs of the users.
However, a lot of 3G-SDI video products in the present markets have no way to pass the test of SDI pathological code. That is to say, if using these products to transmit irregular bit rate signal, the problems, such as splash screen, blank screen, blue screen and so on, will easily happen.
Actually, these 3G-SDI video products can still be used in the transmission of regular bit rate signal to some degree, but the above-mentioned problem will occur in the process of transmitting irregular bit rate signal. These problems appear with great probability under the speed rate of 3G. The reasons that bring about these problems get involved in these two aspects. One is the adopted HD-SDI optical terminal device which is not mature or demerits in design; another is involved in cost. Most of HD-SDI optical terminal devices in the market adopt SFP optical module, which means that using 1.25G and 2.5G SFP optical module to replace video SFP optical module specially for HD-SDI optical terminal device will inevitably cause a lot of error rates when irregular code rate is transmitted. In the application fields of HD-SDI optical terminal device, high requirements for image quality are required. Naturally, the non-smooth screen is not allowable. Therefore, the adoption of video SFP optical module specially for HD-SDI optical terminal device can ensure that these problems such as splash screen, blank screen, and blue screen, will not appear in the process of high-definition image transmission.
3G-SDI video SFP optical transceiver adopts the form factor of SFP optical transceiver module, conformed to SFP MSA and SFF-8472 protocol. Video SFP optical module can be divided into these types according to form factors, such as video SFP optical module with single-transmitter/single-receiver, video SFP optical transceiver with two transmitters/two receivers, and 1.5G/3G/155M video optical module with the asymmetric rate. In addition, the working wavelength and transmission distance of 3G-SDI video SFP optical module respectively are 850nm and 300m when it is matched with multimode optic fiber for the application. The working wavelength and transmission distance respectively are 1310/1550 nm and 10/80 km when it is applied with single-mode optic fiber. This 3G-SD I video SFP optical module is with digital diagnostic function, available to monitor output optical power, bias current, supply voltage, working conditions and so on in real time.
Similar to the SFP optical module used on the exchanger, 3G-SDI SFP optical module is also used to transmit and receive the optical signal. But the difference is that 3G-SDI SFP optical transceiver is used on the optical terminal device, and it plays a key role in the applications of high-definition video transmission.
Generally speaking, the biggest difference between 3G-SDI video devices and 3G-SDI video SFP optical transceiver is that 3G-SDI video SFP optical transceiver module is helpful to solve the problems, such as splash screen, blank screen, blue screen in the process of high-definition image transmission, while 3G-SDI video devices cannot do it. Above all is the information about 3G-SDI video devices and 3G-SDI video SFP optical transceiver.
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