Seamless RF switching system
By using a combination of low-level RF switching switch and power amplifier units in the RF switching system, seamless switching of RF signals is achieved, solving the problems of signal interruption and equipment damage, and ensuring high quality and safe transmission of signals.
Patent Information
- Application Number
- CN202010612332.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2020-06-30
- Publication Date
- 2025-01-10
- Estimated Expiration
- 2040-06-30
AI Technical Summary
The existing RF switching system will cause signal interruption during the switching process, and will not be able to transmit broadcast and television signals under high-quality and safe conditions. Especially during high-power switching, the RF switching switch may burn out, resulting in a powerless output state.
Adopt a seamless RF switching system, including low-level RF switching switches, in-phase distributors, amplifier units, 3dB bridges and phase shifters, millisecond switching is achieved through hot backup and phase fine-tuning, ensuring uninterrupted signal output and allowing amplifiers The unit operates simultaneously or separately to avoid powerless states.
It realizes seamless switching of radio frequency signals, ensuring uninterrupted and high-quality transmission of signals during the switching process, reducing the risk of equipment damage, and providing strong guarantees for safe broadcasting.
Smart Images
Figure CN113873185B_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of radio frequency switching, and in particular to a seamless radio frequency switching system. Background Art
[0002] In order to ensure the safe broadcast of radio and television signals and to transmit the signals uninterruptedly and with high quality, it is necessary to adopt N+1, 1+1 and other transmitter backup systems, and these systems all rely on RF switching switches. High-power RF switching switches are switched when they cannot carry power, otherwise they will cause high-frequency sparking and burn out the contacts. In severe cases, they will burn out the RF switching switch and even the transmission system. Therefore, when performing RF switching, it is generally necessary to turn off the host power first, then switch the RF switching switch to the backup machine, and finally turn on the backup machine power. During the entire switching process, there will be a power-free output state for dozens of seconds, which poses a great hidden danger to safe broadcasting. Summary of the invention
[0003] In order to solve the problem of RF signal interruption during RF switch switching, the present invention provides a seamless RF switching system, which can realize seamless switching of RF signals, so that the signals can be transmitted uninterruptedly, with high quality, economically and safely, providing strong guarantee for safe broadcasting.
[0004] The present invention provides a seamless radio frequency switching system, comprising: two modulators for generating radio frequency signals; a low-level radio frequency switching switch for switching two radio frequency signals; a co-phase distributor for realizing power equal amplitude co-phase output; two power amplifier units for adjusting signal phase and amplitude; a 3dB bridge 1 for synthesizing the same frequency signals output by the two power amplifier units; a phase shifter for signal phase shifting; a 3dB bridge 2 for synthesizing the two signals output after coupling and phase shifting; a through-type power detector 1 for detecting the output radio frequency signal power; a through-type power detector 2 for detecting the absorption load power; and an absorption load for absorbing a small amount of signal frequency passing through the 3dB bridge 2.
[0005] Based on the above technical scheme, the present invention selectively switches the RF signals respectively input by the two modulators through a low-level RF switch. The two modulators can use hot backup, and can achieve millisecond-level switching during switching. Through the in-phase distributor and two power amplifier units with gain adjustment and phase fine-tuning functions, the two power amplifier outputs have equal power and the same phase when reaching the 3dB bridge, ensuring that the seamless RF switching system can switch efficiently, quickly, stably and reliably. When the two power amplifier units switch the working state, the signals are coupled and phase-shifted through two 3dB bridges and phase shifters to ensure uninterrupted output of the RF signal. The two power amplifier units can work simultaneously or independently, and one of the power amplifier units can be pulled out at any time for maintenance to avoid the state of no power output during the signal switching process, thereby ensuring the safe broadcasting of radio and television signals. BRIEF DESCRIPTION OF THE DRAWINGS
[0006] Figure 1 It is a structural diagram of the seamless radio frequency switching system of the present invention.
[0007] Figure 2 It is a structural diagram of the power amplifier unit of the present invention. DETAILED DESCRIPTION
[0008] Figure 1 It is a structural diagram of the seamless radio frequency switching system of the present invention, and the seamless radio frequency switching system includes: two modulators for generating radio frequency signals; a low-level radio frequency switching switch for switching two radio frequency signals; a co-phase distributor for realizing equal-amplitude co-phase output of power; two power amplifier units for adjusting signal phase and amplitude; a 3dB bridge 1 for synthesizing the same-frequency signals output by the two power amplifier units; a phase shifter for signal phase shifting; a 3dB bridge 2 for synthesizing the two signals output after coupling and phase shifting; a through-type power detector 1 for detecting the output radio frequency signal power; a through-type power detector 2 for detecting the absorption load power; an absorption load for absorbing a small amount of signal frequency passing through the 3dB bridge 2.
[0009] The two modulators transmit the RF signals to the low-level RF switching switch respectively. The modulated output level is generally in the milliwatt level. The two modulators can use hot backup. The RF switching switch can be switched at any time under low level, and the switching can be achieved in milliseconds. The two RF signals are switched to the in-phase distributor through the low-level RF switching switch. The in-phase distributor outputs the two signals with equal power and the same phase to the two power amplifier units respectively. After gain adjustment, phase fine-tuning and power amplification in the power amplifier unit, the signal is transmitted to the two input ends of the 3dB bridge 1 respectively. Under different working conditions, the two output ends of 3dB bridge one output two signals of the same frequency. One signal is connected to an input end of 3dB bridge two after passing through a phase shifter. The signal is phase-shifted in the phase shifter according to the working state of the power amplifier unit, and the other signal is directly output to the other input end of 3dB bridge two; two signals with equal power and a phase difference of 90° are output to the two input ends of 3dB bridge two respectively. After coupling and shifting, one signal passes through through-type power detector one to output a radio frequency signal, and the other signal passes through through-type power detector two and is connected to an absorption load.
[0010] When power amplifier unit 1 works alone, the phase shifter is placed at 180°, and all the power of power amplifier unit 1 is output to the RF output port; when power amplifier unit 2 works alone, the phase shifter is placed at 0°, and all the power of power amplifier unit 2 is output to the RF output port; when two power amplifier units work simultaneously, the phase shifter is placed at 90°, and all the power of the two power amplifier units is output to the RF output port; each power amplifier unit can reach the rated power output of the transmitter, and when the two power amplifier units output at full power together, the output power is approximately twice the rated power of the transmitter.
[0011] When one power amplifier unit needs to be repaired or maintained, both power amplifier units are turned on at the same time. When the phase shifter is adjusted to 0°, power amplifier unit 1 can be turned off for repair; when the phase shifter is adjusted to 180°, power amplifier unit 2 can be turned off for repair. During the entire operation, the power output of the RF output port will be maintained at ≥ rated power, so that the RF signal is uninterrupted during signal switching, ensuring the safe broadcast of the signal.
[0012] Figure 2 It is a structural diagram of the power amplifier unit of the present invention, which includes: a front-stage module for signal gain adjustment and phase fine-tuning; and a power amplifier module for signal power amplification.
[0013] After the signal passes through the in-phase distributor and the power amplifier unit with gain adjustment and phase adjustment, it can output two signals with equal power and the same phase to the 3dB bridge 1, ensuring that the seamless RF switching system can switch efficiently, quickly, stably and reliably.
[0014] The embodiments of the present invention are described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments and various changes can be made thereto within the knowledge scope of ordinary technicians in the field.
Claims
1. A seamless radio frequency switching system, characterized in that: include: two modulators for generating radio frequency signals; Low-level RF switch, used for switching between two RF signals; In-phase distributor to achieve equal-amplitude and in-phase output of power; Two power amplifier units, used for adjusting signal phase and amplitude; 3dB bridge 1, used for synthesizing the same frequency signals output by two power amplifier units; Phase shifter, used for signal phase shift; 3dB bridge 2, used for synthesizing two signals output after coupling and phase shifting; The through-type power detector 1 is used to detect the output RF signal power; the through-type power detector 2 is used to detect the absorption load power; the absorption load is used to absorb a small amount of signal frequency passing through the 3dB bridge 2; The two modulators transmit the radio frequency signals to the low-level radio frequency switching switch respectively; the two radio frequency signals are switched and output to the in-phase distributor through the low-level radio frequency switching switch, and the in-phase distributor outputs the two signals with equal power and the same phase to the two power amplifier units respectively; the signals are respectively transmitted to the two input ends of the 3dB bridge 1 after gain adjustment, phase fine-tuning and power amplification in the power amplifier unit, and under different working conditions of the two power amplifier units, the two output ends of the 3dB bridge 1 output two same-frequency signals, one signal is connected to one input end of the 3dB bridge 2 after passing through the phase shifter, the signal is phase-shifted in the phase shifter according to the working state of the power amplifier unit, and the other signal is directly output to the other input end of the 3dB bridge 2; the two signals with equal power and a phase difference of 90° are respectively output to the two input ends of the 3dB bridge 2, and after coupling and shifting, one signal passes through the through-type power detector 1 to output the radio frequency signal, and the other signal passes through the through-type power detector 2 to be connected to the absorption load.
2. The seamless radio frequency switching system according to claim 1, characterized in that: The two modulators can be used in hot standby mode.
3. The seamless radio frequency switching system according to claim 1, characterized in that: The two power amplifier units are respectively a power amplifier unit 1 and a power amplifier unit 2. When the power amplifier unit 1 works alone, the phase shifter is placed at a 180° position, and all the power of the power amplifier unit 1 is output to the RF output port; when the power amplifier unit 2 works alone, the phase shifter is placed at a 0° position, and all the power of the power amplifier unit 2 is output to the RF output port; When the two power amplifier units work at the same time, the phase shifter is placed at 90°, and all the power of the two power amplifier units is output to the RF output port.
Citation Information
Patent Citations
Seamless radio frequency switching system
CN212211181U