Time Division Multiplexing Advantages

TDM combines multiple digital signals into a single serial digital bit stream. A specialized circuit, called a serializer, allocates parallel input streams into time slots in the serial output. In a fiber optic system, the serial bit stream is transmitted as a single wavelength down a  fiber optic cable. On the far end of the channel, a deserializer reconstructs the original parallel signal from the serial bit stream as shown in Figure 1. The serial data rate must be sufficiently fast to ensure no data is lost. Fiber optic transmitters and receivers for high resolution AV signals typically operate at a 4 to 6Gbps data rate.

Figure 1 a Serializer – Deserializer

TDM is used to transmit a wide variety of signals, including HDMI, DVI, 3G-SDI, RGB, HD and SD component video, S-video, composite, USB, audio, and RS-232 control. In modern fiber optic AV systems, analog video and audio are converted to digital signals, avoiding nonlinear effects that plague direct optical conversion of analog signals. Digital transmission ensures high-resolution video is transmitted pixel-for-pixel along the fiber optic cable.

Figure 2 TDM Fiber Optic Transmitter and Receiver for HDMI/DVI, Audio and Control

The transmitter in Figure 2 accepts HDMI/DVI video, stereo audio, and RS-232 control signals. The multiplexer combines the signals as a serial stream of digital pulses. An electrical-to-optical – E-to-O converter changes the digital pulses to light pulses at a single wavelength for transmission down the fiber. The receiver on the far end converts the signal from optical to electrical – O-to-E before deserializing to restore the original signal.

Sopto supplies high quality communication products, like  1-64 Channels Video Multiplexers, Phone Optical Multiplexers and so on. Please contact a Sopto representative by calling 86-755-36946668, or by sending an email to info@sopto.com.