Applications of Digital Receivers
A digital receiver is a digital receiver that digitizes the signal through an analog-to-digital converter and uses digital signal processing technology to achieve frequency conversion, filtering, and demodulation.
With the advancement of digital signal processing theory and large-scale integrated circuit technology, digital receivers featuring high-speed analog-to-digital converters and digital signal processing circuits were derived from the receiver system in the 1980s. The digital receiver has high sensitivity and precision, good stability, flexible design and can realize complex functions, and has become the most promising system in the receiver. At the current device level, the analog-to-digital conversion of digital receivers is usually completed at the intermediate frequency. Compared with the radio frequency signal received by the antenna, the intermediate frequency signal has to undergo a nonlinear process of mixing and filtering, which introduces harmonics and causes signal noise. Scatter increases. So the digitization of IF is not an ideal digital receiver solution. The ideal digital receiver in the future will complete the digital receiver at the radio frequency side.
Digital receivers are widely used in communications, radar, navigation systems, electronic countermeasure systems, identification systems, civilian radios and televisions, and are an important system for the future development of receivers.
A set-top box is a kind of civilian digital receiver, which uses a satellite communication network as a transmission platform and a TV as a user terminal. The commonly used receiver is the digital satellite receiver (DVB-S), its basic function is to receive digital broadcast programs, it embodies multimedia, computer, digital compression coding, descrambling algorithm, encryption and decryption algorithm, communication technology and network technology. The level of development.