Patent ID: 11894942
Assignee: NANNING FULIAN FUGUI PRECISION INDUSTRIAL CO., LTD.
Field: Audio-visual technology (Electrical engineering)
Classification: CPC H | IPC H

Claim 3:
4. The communication system based on DOCSIS protocol according to claim 1, wherein the secondary filtering path comprises:
the second low-pass filter, the input end of the second low-pass filter being electrically connected to the frequency divider, the second low-pass filter being configured for passing the downstream signal with a bandwidth of 108 MHz˜684 MHz;
the first synthesizer, the first input of the first synthesizer being electrically connected to the output of the second low-pass filter;
the first RF switch, the common end of the first RF switch being electrically connected to the output end of the first synthesizer;
a third low-pass filter, an input end of the third low-pass filter being electrically connected to a second end of the first RF switch, the third low-pass filter being configured for passing the downstream signal with a bandwidth of 108 MHz˜492 MHz;
a second synthesizer, a first input end of the second synthesizer being electrically connected to an output of the third low-pass filter;
a second RF switch, a common end of the second RF switch being electrically connected to an output end of the second synthesizer, a first end of the second RF switch being electrically connected to the first modulation and demodulation unit, the second RF switch being configured for transmitting the downstream signal with the bandwidth of 108 MHz˜492 MHz to the first modulation and demodulation unit;
a second phase regulator, an input end of the second phase regulator being electrically connected to the second modulation and demodulation unit, the second phase regular being configured for phase adjustment of the upstream signal sent by the second modulation and demodulation unit;
a third power amplifier, an input end of the third power amplifier being electrically connected to an output end of the second phase regulator, an output end of the third power amplifier being electrically connected to a second input end of the second synthesizer, the third power amplifier being configured for adjusting a power of the phase adjusted signal and output a signal with an opposite phase and a same power as the upstream signal sent by the second modulation and demodulation unit;
the system-on-a-chip, electrically connected to the third power amplifier, and configured for controlling a magnification of the third power amplifier.