STB (Set-Top Box) is conversion equipment converting digital TV signal into analog signal. It decodes and restores image and sound signals after digital compression to generate simulative video and sound signals, and provides high-quality TV programs to the audiences through TV display and stereo equipment. STB is also a multimedia terminal which has decoding function of digital signal and can analyze and decipher user authorization information.
Additional functional business with different requirements and actual network deployment bring more project challenges. Wideband data rate changes at any time and delay will affect duplex communication. The difference of sophisticated video decoders will cause the problem of equipment operability. The equipment may be installed on the network that business provider cannot control or serve as a part of network adopting low standard, and then it is in the control of unbalanced QoS. The appearance and application of supercapacitor provides technical support for stable operation of STB.