Control device for two-way radio frequency signal

Abstract

The control device for two-way radio frequency signals is composed of a first microwave radio frequency signal switch, a bypass module, a first filter, an amplifier and a grouper to form a full-band signal downlink path; after the second microwave radio frequency signal switch and the second filter are connected in sequence, Between the input terminal of the first microwave radio frequency signal switch and the output terminal of the bypass module, the second microwave radio frequency signal switch, the second filter, the amplifier and the grouper form the first sub-frequency band downlink path; the third microwave radio frequency signal switch and the second microwave radio frequency signal switch After the three filters are connected in sequence, they are connected in parallel at the output end of the amplifier and the input end of the first microwave radio frequency signal switch, and the grouper, the third microwave radio frequency signal switch and the third filter form the second frequency division uplink; the first microwave radio frequency The signal switch, the second microwave and radio frequency signal switch and the third microwave and radio frequency signal switch are controlled to be turned on through the switch, so as to realize the comprehensive control of the bidirectional radio frequency signal.

Description

technical field [0001] The invention belongs to the field of radio frequency signal processing, and in particular relates to a control device for bidirectional radio frequency signals. Background technique [0002] DVB, the abbreviation of Digital Video Broadcasting, is a series of internationally recognized digital TV open standards maintained by the DVB project. DVB system transmission methods are as follows: satellite (DVB-S and DVB-S2); cable (DVB-C); terrestrial wireless (DVB-T); handheld terrestrial wireless (DVB-H). The main difference between these transmission methods is the modulation method used, because the requirements for the frequency bandwidth of different applications are different. DVB-S using high-frequency carrier uses QPSK modulation, DVB-C using low-frequency carrier uses QAM-64 modulation, and DVB-T using VHF and UHF carrier uses COFDM modulation DVB-S (ETS 300 421) is Digital Satellite Broadcasting System Standard. Satellite transmission has the ch...

AI Technical Summary

Problems solved by technology

The current common solution is to choose parallel transmission, but due to the large transmission loss of the downlink radio frequency signal in the coaxial cable of the DVB-T system, it is usually necessary to switch the multi-satellite radio frequency signal, or any device at the same node, to provide Only by increasing the compensation function of the signal gain can the subsequent signal transmission and use requirements be met

It is precisely because of the signal gain of the DVB-T downlink signal by the signal gain compensation circuit in the line that the forward and reverse feed loop amplification is formed at the frequency overlapping part of DVB-T and DVB-C, which leads to the imbalance of the amplifying unit circuit, resulting in The self-excitation phenomenon of the system signal often causes irregular fluctuations in the transmission of radio frequency signals, which affects the signal quality

Images