A terrestrial digital television signal receiving device and method

Abstract

The present invention relates to a terrestrial digital television signal receiving device and method. The device includes an antenna, a tuner, a demodulator and a decoder connected in sequence, and a low noise amplifier and an analog signal are connected between the antenna and the tuner. switch, the terrestrial digital TV signal received by the antenna is divided into two paths, one path enters the first input end of the analog switch through the low noise amplifier, and the other path directly enters the second input end of the analog switch, and the output end of the analog switch is connected to the tuner, and the built-in signal monitoring and switch control module in the demodulator, the signal monitoring and switch control module is used to detect the signal strength of the intermediate frequency signal input to the demodulator through the tuner, and the detected current The signal strength is compared with a preset signal strength threshold, and the analog switch is controlled to turn on its first input end or second input end according to the comparison result. The invention improves the threshold of terrestrial digital television signal reception by 2.3dB to 3.6dB.

Description

technical field [0001] The invention relates to the technical field of terrestrial digital television, in particular to a terrestrial digital television signal receiving device and method. Background technique [0002] With the rapid development of terrestrial digital TV technology, the receiving ability of receiving equipment has been greatly improved. At present, the reception range of terrestrial digital TV receiving equipment is mainly affected by the performance of the front-end tuner Tuner and demodulator demodulator, such as figure 1 Shown: The signal is received from the antenna 1 and enters the tuner 2; the tuner 2 puts the received signal into the intermediate frequency output through mixing; the demodulator 3 demodulates useful information from the received intermediate frequency signal , output in the form of a TS code stream; the decoder 4 converts the input standard TS code stream into a code stream that can be played on audio and video equipment. [0003] Fr...

AI Technical Summary

Problems solved by technology

With the continuous advancement of technology, the performance of the tuner and demodulator has reached the bottleneck, and it is difficult to greatly improve the performance. Therefore, the performance can be improved by a few tenths of a dB to increase the receiving range of terrestrial digital TV receiving equipment. very difficult

[0004] In the prior art, according to the multi-stage amplification principle of the system, in order to increase the system amplification gain and increase the sensitivity to the tiny front-stage input, the most effective way is to increase the gain of the front-end stage, but this brings two new problems: First, the noise of the front stage will also be amplified

This requires the noise of the front-end amplifier to be as small as possible; second, it is easy to cause system input signal saturation, that is, the amplification circuit is saturated and blocked in the case of large signal input.

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