A co-transmission system based on radio frequency feeders

Abstract

The utility model relates to the field of radio frequency engineering and transmission technology, concretely relates to a kind of co-transmission system based on radio frequency feeder, including integrated in the feeder antenna of the signal separation circuit of feeder branch distributor and feeder transmitting module of optical fiber repeater remote machine;Feeder transmitting module is output after direct current and radio frequency signal compound;Feeder branch distributor distributes compound signal to multiple branch;Signal separation circuit in feeder antenna is separated out direct current and pure radio frequency signal by parallel direct-current voltage-stabilized power supply branch and radio frequency signal transmission branch, respectively for antenna function module power supply and realizes signal radiation.The utility model synchronously transmits energy and signal by single coaxial cable, need not additional power line arrangement, significantly reduce deployment cost and complexity, improve the flexibility and scalability of system simultaneously, support multifunctional antenna stable operation.

Description

Technical Field

[0001] This utility model relates to the field of radio frequency engineering and transmission technology, specifically to a common transmission system based on radio frequency feeders. Background Technology

[0002] As indoor building communication systems become increasingly feature-rich, the functional and performance requirements of their related equipment, especially antenna terminals, are also constantly rising. Traditional communication systems typically use RF coaxial cables and dedicated splitters to construct a signal transmission network, achieving RF signal coverage and radiation through indoor antennas. In this type of solution, the antenna acts only as a passive signal radiating terminal, completing basic communication functions without external power supply. The system structure is relatively simple, and the deployment cost is low.

[0003] However, to meet the demands of modern communication and IoT applications, such as indoor positioning, status monitoring, and remote control, antennas need to integrate diverse functions including Bluetooth signal radiation, self-testing, and control. These new functions all require independent power supplies. Using an additional power network to power the antennas would significantly increase the complexity and cost of system construction, while also limiting the system's flexibility and scalability.

[0004] Therefore, how to achieve synchronous power transmission in the existing radio frequency signal transmission network, so as to provide stable power to the multi-functional antenna without adding new power supply lines, has become an urgent technical problem to be solved. Utility Model Content

[0005] To address the above technical problems, this utility model provides a technical solution for a common transmission system based on radio frequency feeders.

[0006] The technical problem solved by this utility model can be achieved by the following technical solution:

[0007] A common transmission system based on an RF feeder includes:

[0008] A power-fed transmitter module is integrated into the transmitter port of the remote unit of the fiber optic repeater. The integrated output terminal of the power-fed transmitter module outputs a composite signal of radio frequency signal and DC power.

[0009] A power supply branch distributor, wherein the composite signal input terminal of the power supply branch distributor is connected to the integrated output terminal of the power supply transmitter module;

[0010] A feed antenna, wherein the feed antenna integrates a signal separation circuit, and the input terminal of the signal separation circuit is connected to the direct output terminal or the coupled output terminal of the feed branch splitter;

[0011] The signal separation circuit includes a parallel DC regulated power supply branch and a radio frequency signal transmission branch to separate the received composite signal into DC and radio frequency signals.

[0012] Preferably, the radio frequency signal input terminal of the power-fed transmitter module is connected to the transmitter port of the fiber optic repeater remote unit, and the DC input terminal of the power-fed transmitter module is connected to an external DC power supply.

[0013] Preferably, the fed transmitter module includes:

[0014] A first DC blocking capacitor is connected between the radio frequency signal input terminal and the integrated output terminal;

[0015] A first radio frequency choke inductor is connected between the DC input terminal and the integrated output terminal.

[0016] Preferably, the power supply branch distributor includes:

[0017] The second DC blocking capacitor has its first end connected to the second transmission line and its second end connected to the ground terminal. A load resistor is connected between the second DC blocking capacitor and the ground terminal.

[0018] One end of the second transmission line is connected to the first transmission line, and the other end is connected to the coupling output terminal. The first transmission line is connected between the composite signal input terminal and the through output terminal.

[0019] The second RF choke inductor has its first end connected to the first transmission line and its second end connected to the second transmission line.

[0020] Preferably, the DC regulated power supply branch includes:

[0021] The third radio frequency choke inductor, the first end of which is connected to the input terminal of the signal separation circuit;

[0022] The first voltage regulator chip has its input terminal connected to the second terminal of the third RF choke inductor, and its output terminal outputs a first DC voltage.

[0023] The second voltage regulator chip has its input terminal connected to the output terminal of the first voltage regulator chip, and its output terminal outputs a second DC voltage.

[0024] A current-limiting resistor is connected in series between the first voltage regulator chip and the second voltage regulator chip to limit the current flowing through the second voltage regulator chip.

[0025] Preferably, the DC regulated power supply branch includes multiple filter networks, which are connected in parallel to each node of the DC regulated power supply branch to filter out voltage ripple at different nodes.

[0026] Preferably, the filtering network includes:

[0027] The first filter network includes a first filter capacitor and a second filter capacitor, which are connected in parallel between the third RF choke inductor and the first voltage regulator chip.

[0028] The second filter network includes a third filter capacitor and a fourth filter capacitor, which are connected in parallel between the first voltage regulator chip and the current limiting resistor.

[0029] The third filtering network includes a fifth filtering capacitor and a sixth filtering capacitor, which are connected in parallel between the current limiting resistor and the second voltage regulator chip.

[0030] The fourth filter network includes a seventh filter capacitor and an eighth filter capacitor, which are connected in parallel between the second voltage regulator chip and the load.

[0031] Preferably, the radio frequency signal transmission branch includes:

[0032] The third DC blocking capacitor, the first end of which is connected to the input terminal of the signal separation circuit;

[0033] A radio frequency amplifier, wherein the input terminal of the radio frequency amplifier is connected to the second terminal of the third DC blocking capacitor;

[0034] A fourth DC blocking capacitor, the first end of which is connected to the output terminal of the RF amplifier;

[0035] A detector diode, the input terminal of which is connected to the second terminal of the fourth DC blocking capacitor;

[0036] The signal conditioning and output buffer module is connected to the output terminal of the detector diode.

[0037] Preferably, the signal conditioning and output buffer module includes a first operational amplifier and a second operational amplifier;

[0038] The non-inverting input of the first operational amplifier is connected to the output of the detector diode through a seventh resistor, the inverting input of the first operational amplifier is connected to the ground through an eighth resistor, and a ninth resistor is connected in series between the inverting input and the output of the first operational amplifier.

[0039] The non-inverting input of the second operational amplifier is connected to the output of the first operational amplifier through the tenth resistor, the inverting input of the second operational amplifier is connected to its output, and the output of the second operational amplifier is connected to an external load through the eleventh resistor.

[0040] Preferably, the radio frequency signal transmission branch further includes:

[0041] The first LC filter module is connected between the third DC blocking capacitor and the RF amplifier;

[0042] An attenuation module is connected between the first LC filter module and the RF amplifier;

[0043] The second LC filter module is connected in parallel between the RF amplifier and the fourth DC blocking capacitor.

[0044] Beneficial effects: This utility model constructs a distributed network architecture that integrates power supply and radio frequency signal transmission by realizing the co-transmission of DC power supply and radio frequency signal in a single coaxial feeder. This not only effectively avoids the complexity and cost of deploying additional power lines, but also significantly improves the flexibility and scalability of the system, enabling the multi-functional antenna to operate stably without the need for an independent power supply. Attached Figure Description

[0045] Figure 1 This is a schematic diagram of the system working principle of this utility model;

[0046] Figure 2 This is a system architecture diagram of the present invention;

[0047] Figure 3 This is a circuit diagram of the power supply and transmission module of this utility model;

[0048] Figure 4 This is a circuit diagram of the power supply branch distributor of this utility model;

[0049] Figure 5 This is a branch diagram of the DC regulated power supply of this utility model;

[0050] Figure 6 This is a branch diagram of radio frequency signal transmission and processing according to this utility model;

[0051] Explanation of reference numerals in the attached diagram: 1. Feeding transmitter module; 2. Feeding branch distributor; 3. DC regulated power supply branch; 4. RF signal transmission and processing branch; 5. Feeding antenna; 6. Fiber optic repeater remote unit; 7. Coaxial cable; 11. RF signal input terminal; 12. DC signal input terminal; 13. Composite signal output terminal; 21. Composite signal input terminal; 22. Straight-through output terminal; 23. Coupled output terminal; 24. First transmission line; 25. Second transmission line; 41. First LC filter module; 42. Attenuation module; 43. Second LC filter module; 44. Signal conditioning and output buffer module. Detailed Implementation

[0052] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0053] It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0054] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but this is not intended to limit the present invention.

[0055] Reference Figures 1 to 6 This utility model provides a common transmission system based on radio frequency feeders, comprising:

[0056] The power supply transmitter module 1 is integrated into the transmitter port of the fiber optic repeater remote unit 6. The integrated output terminal 13 of the power supply transmitter module 1 outputs a composite signal of radio frequency signal and DC power.

[0057] The power supply branch distributor 2 has a composite signal input terminal 21 connected to the integrated output terminal 13 of the power supply transmitter module 1.

[0058] The feed antenna 5 has an integrated signal separation circuit inside. The input terminal RF_IN of the signal separation circuit is connected to the direct output terminal 22 or the coupled output terminal 23 of the feed branch distributor 2.

[0059] The signal separation circuit includes a parallel DC regulated power supply branch 3 and a radio frequency signal transmission branch 4 to separate the received composite signal into DC and radio frequency signals.

[0060] Specifically, in this embodiment of the invention, in order to address the problems of high cost, complex deployment, and poor flexibility caused by the need for additional power supply lines for antennas in traditional indoor communication systems, DC power and radio frequency signals are transmitted synchronously through radio frequency feeders, thus avoiding the construction of an independent power network. This enables the simultaneous transmission of energy and information on a single coaxial cable, significantly improving system integration and scalability.

[0061] Specifically, the system reuses existing RF coaxial cable 7 for composite signal transmission, providing stable DC power to the multi-functional antenna without altering the original communication architecture, supporting enhanced functions such as Bluetooth communication, status monitoring, and remote control. The fiber optic repeater remote unit 6, the power supply branch splitter 2, and the power supply antenna 5 are connected via coaxial cable 7, forming a complete shared transmission network. The power supply transmitter module 1 efficiently integrates DC power and RF signals, outputting them to the transmission line from the integrated output terminal 13. The power supply branch splitter 2 distributes the composite signal to multiple branches as needed; its direct output terminal 22 or coupled output terminal 23 can be connected to different power supply antennas 5, enabling flexible topology expansion and area coverage, while maintaining dual-path synchronous transmission of power and signal during the distribution process. The signal separation circuit inside the power supply antenna 5 extracts DC power to power the antenna's built-in functional modules through parallel DC regulated power supply branch 3 and RF signal transmission branch 4, filtering out pure RF signals for radiation, ultimately achieving integrated operation of communication and power supply.

[0062] The power distribution unit 2 used in this system is a radio frequency power distributor and coupler with power distribution function. It can maintain the continuity and stability of DC power supply while distributing radio frequency signals in multiple paths, ensuring that each branch terminal can reliably obtain the power required for operation.

[0063] In a preferred embodiment of the present invention, the radio frequency signal input terminal 11 of the power supply transmitting module 1 is connected to the transmitting port of the fiber optic repeater remote unit 6, and the DC input terminal 12 of the power supply transmitting module 1 is connected to an external DC power supply.

[0064] Specifically, in this embodiment of the invention, the RF signal input terminal 11 of the feed transmitter module 1 is directly connected to the transmitter port of the fiber optic repeater remote unit 6, while its DC input terminal 12 is connected to an externally provided 5V DC power supply. The feed transmitter module 1 is integrated into the existing equipment's transmission link using a series-parallel connection. Through internal integration circuitry, the input RF signal and DC power supply are efficiently fused to form a composite signal, which is then output from the integrated output terminal 13. This design, based on widely deployed fiber optic repeaters as the signal source, successfully achieves low-voltage DC power loading at the transmitter port without altering the original RF signal transmission characteristics, thereby providing remote power to each feed antenna 5 in the subsequent distributed antenna network.

[0065] In a preferred embodiment of this utility model, the fed transmitting module 1 includes:

[0066] The first DC blocking capacitor C1 is connected between the radio frequency signal input terminal 11 and the integrated output terminal 13;

[0067] The first radio frequency choke inductor L1 is connected between the DC input terminal 12 and the integrated output terminal 13.

[0068] Specifically, in the embodiments of this utility model, referring to Figure 3 The radio frequency (RF) signal input at the RF signal input terminal 11 is coupled to the integrated output terminal 13 via a first DC blocking capacitor C1. This first DC blocking capacitor C1 blocks DC current while allowing the RF signal to pass through. Simultaneously, the external DC power supply introduced at the DC input terminal 12 is fed into the integrated output terminal 13 through a first RF choke inductor L1. This first RF choke inductor L1 suppresses RF signal interference into the DC power supply side and provides a low-impedance path for DC power supply. Through this method, RF energy and DC power are efficiently fused at the integrated output terminal 13 to form a composite signal, which is then output to the subsequent transmission network.

[0069] In a preferred embodiment of this utility model, the power supply branch distributor 2 includes:

[0070] The second DC blocking capacitor C2 has its first end connected to the second transmission line 25 and its second end connected to the ground terminal. A load resistor R0 is connected between the second DC blocking capacitor C2 and the ground terminal.

[0071] One end of the second transmission line 25 is connected to the first transmission line 24, and the other end is connected to the coupling output terminal 23. The first transmission line 24 is connected between the composite signal input terminal 21 and the through output terminal 22.

[0072] The second RF choke inductor L2 has its first end connected to the first transmission line 24 and its second end connected to the second transmission line 25.

[0073] Specifically, in the embodiments of this utility model, referring to Figure 4 The composite signal is received from the power supply branch distributor 2 through the composite signal input terminal 21. The composite signal is transmitted through the first transmission line 24, in which most of the radio frequency energy and DC component are directly delivered to the through output terminal 22; the other part of the energy is coupled to the coupling output terminal 23 through the second transmission line 25.

[0074] The second RF choke inductor L2 provides a path for DC power supply, ensuring that the DC component can be simultaneously distributed to the through and coupled output terminals; the second DC blocking capacitor C2 is used to block DC signals from entering the ground branch, and works with the load resistor R0 to maintain the directional coupling and matching characteristics of the RF signal, thereby achieving synchronous and stable transmission of RF energy and DC power during the multi-path distribution process.

[0075] In a preferred embodiment of this utility model, the DC regulated power supply branch 3 includes:

[0076] The third RF choke inductor L3, the first end of which is connected to the input terminal RF_IN of the signal separation circuit;

[0077] The first voltage regulator chip U1 has its input terminal connected to the second terminal of the third RF choke inductor L3, and its output terminal outputs a first DC voltage.

[0078] The second voltage regulator chip U2 has its input terminal connected to the output terminal of the first voltage regulator chip U1, and its output terminal outputs a second DC voltage.

[0079] A current-limiting resistor R is connected in series between the first voltage regulator chip U1 and the second voltage regulator chip U2 to limit the current flowing through the second voltage regulator chip U2.

[0080] Specifically, in the embodiments of this utility model, referring to Figure 5 After the composite signal enters from the input terminal RF_IN, the third RF choke inductor L3 provides a low-impedance path for the DC component, guiding it to the subsequent voltage regulator circuit, while effectively suppressing the RF signal from entering the DC power supply branch. The DC power is then delivered to the first voltage regulator chip U1 via the third RF choke inductor L3. This chip is an L7805C model, which can stably convert the input voltage into a 5V, 500mA first DC output.

[0081] More specifically, considering the potential overcurrent risk in the back-end circuits and the differences in power requirements among different functional modules, a current-limiting resistor R is connected in series at the output of the first voltage regulator chip U1 to improve power supply safety and reliability. This current-limiting resistor R is used to precisely limit the current flowing to subsequent circuits, providing overcurrent protection, ensuring that the first-stage voltage regulator output operates within a safe current range, and providing stable input conditions for the subsequent second-stage voltage regulator.

[0082] Then, the current-limited 5V voltage is input to the second voltage regulator chip U2, which is also an L7805C model. Through secondary voltage regulation and voltage division, it generates a second DC voltage of 3.3V and 250mA. The current-limiting resistor R here further ensures that the current flowing into the second voltage regulator chip U2 is within a safe threshold, enhancing the overall reliability of the system.

[0083] Through the combination of the two-stage voltage regulation and current limiting, this branch can provide stable and isolated multi-channel operating power to modules with different voltage requirements inside the antenna, such as Bluetooth communication units and control circuits, while ensuring the pure transmission of radio frequency signals, and ultimately achieving efficient and reliable separation of power and signal.

[0084] In a preferred embodiment of the present invention, the DC regulated power supply branch 3 further includes multiple filter networks, which are connected in parallel to each node of the DC regulated power supply branch 3 to filter out voltage ripple at different nodes.

[0085] Specifically, since the radio frequency components contained in the composite signal may generate high-frequency noise on the DC path, and the switching operation of the voltage regulator chip also introduces ripple, these interferences, if not suppressed, will affect the power supply quality and the stability of the downstream circuits. In this embodiment of the invention, the DC regulated power supply branch 3 is equipped with multiple sets of filter networks at key nodes, referring to... Figure 6 Specifically, it includes:

[0086] The first filter network includes a first filter capacitor C31 and a second filter capacitor C32, which are connected in parallel between the third RF choke inductor L3 and the first voltage regulator chip U1.

[0087] The second filter network includes a third filter capacitor C33 and a fourth filter capacitor C34, which are connected in parallel between the first voltage regulator chip U1 and the current limiting resistor R.

[0088] The third filtering network includes a fifth filter capacitor C35 and a sixth filter capacitor C36, which are connected in parallel between the current limiting resistor R and the second voltage regulator chip U2.

[0089] The fourth filtering network includes a seventh filter capacitor C37 and an eighth filter capacitor C38, which are connected in parallel between the second voltage regulator chip U2 and the load.

[0090] Specifically, since composite signals inevitably introduce radio frequency noise during transmission, and the switching noise of the voltage regulator chip itself is also superimposed on the DC level, failure to suppress these ripples will directly lead to a decline in power quality, thereby affecting the normal operation of sensitive circuits such as the downstream Bluetooth module and control unit, and even causing malfunctions or performance degradation. Therefore, in this embodiment of the invention, a multi-stage filtering network is set in the DC regulated power supply branch to filter out noise interference of different frequency bands and types in stages, as described below:

[0091] The first filter network (C31, C32) is located at the DC input front end and mainly undertakes the pre-filtering function. It uses a combination of capacitors with different capacitance values ​​(usually large capacitors to filter low frequencies and small capacitors to filter high frequencies) to perform wideband noise filtering on the DC power after it has been initially isolated by the third RF choke inductor L3, so as to provide a relatively clean input voltage for the first-stage voltage regulator chip U1 and improve its working stability.

[0092] The second filter network (C33, C34) is located at the output of the first voltage regulator chip U1. Its main function is to suppress the output ripple and switching noise generated during the voltage regulation process of the chip. At the same time, it plays the role of energy storage and buffering to cope with the instantaneous changes in load current, ensure that the output 5V voltage is stable and reliable, and provide a high-quality input source for the subsequent current limiting resistor R and the second-stage voltage regulator circuit.

[0093] The third filter network (C35, C36) is placed after the current-limiting resistor R and before the second voltage regulator chip U2. It is used to further filter out the noise that may be coupled from the previous stage and the thermal noise introduced by the current-limiting resistor, so as to ensure the cleanliness of the voltage input to the second voltage regulator chip U2 and ensure its accuracy and efficiency in secondary voltage regulation.

[0094] The fourth filter network (C37, C38) is located at the final output of the entire power supply branch. Its core function is to perform final shaping and smoothing of the 3.3V voltage output by the second voltage regulator chip U2, thoroughly filter out high-frequency switching noise and line interference, and ensure that the DC voltage delivered to each load module has an extremely low ripple coefficient and high stability, meeting the stringent power supply quality requirements of the integrated circuit inside the antenna.

[0095] Through the synergistic effect of the above four-stage filtering network, the DC regulated power supply branch achieves noise suppression throughout the entire process from input to output, significantly improving the electromagnetic compatibility (EMC) and power integrity of the system, and ultimately ensuring the long-term stable operation of the multi-functional antenna in complex electromagnetic environments.

[0096] In a preferred embodiment of this utility model, the radio frequency signal transmission branch 4 includes:

[0097] The third DC blocking capacitor C3, the first end of which is connected to the input terminal RF_IN of the signal separation circuit;

[0098] A radio frequency amplifier RF, the input terminal of which is connected to the second terminal of the third DC blocking capacitor C3;

[0099] The fourth DC blocking capacitor C50, the first end of which is connected to the output terminal of the RF amplifier RF;

[0100] Detector diode D, the input terminal of which is connected to the second terminal of the fourth DC blocking capacitor C50;

[0101] The signal conditioning and output buffer module 44 is connected to the output terminal of the detector diode D.

[0102] Specifically, in the embodiments of this utility model, referring to Figure 6 After the composite signal enters the RF signal transmission branch 4 from the input terminal RF_IN, it first passes through the third DC blocking capacitor C3 with a nominal level of 5.5dBm. This capacitor effectively blocks the DC component in the composite signal, allowing only the RF signal to pass through, thus achieving initial separation of AC and DC signals. The clean RF signal is then sent to the RF amplifier RF for signal amplification. This amplifier has a gain of 21dB, which can effectively compensate for the path loss of the signal during transmission and ensure that its strength meets the requirements of subsequent processing.

[0103] Considering that DC offset may be introduced during the amplification of the RF signal, and that the subsequent detection circuit needs to operate under pure AC conditions to ensure measurement accuracy, a fourth DC blocking capacitor C50 is set at the output of the RF amplifier. This capacitor is used to block the DC component, ensuring that the signal input to the detection stage is a pure RF AC signal. After the amplified RF signal passes through the fourth DC blocking capacitor C50 to filter out any possible DC offset, it is sent to the detector diode D. The detector diode D uses its nonlinear characteristics to perform envelope detection on the RF signal, converting it into a low-frequency voltage signal proportional to the amplitude of the RF signal. This signal contains accurate RF strength information, providing a crucial input for subsequent processing.

[0104] Accordingly, the low-frequency voltage signal is further fed into the signal conditioning and output buffer module 44. The core of this module consists of a two-stage operational amplifier circuit, including a first operational amplifier OP1 responsible for signal amplification and a second operational amplifier OP2 responsible for output buffering and impedance matching. It can amplify, condition, and transform the impedance of the detected low-frequency signal, and finally provide a stable and powerful standard signal for the back-end system.

[0105] In a preferred embodiment of the present invention, the signal conditioning and output buffer module 44 includes a first operational amplifier OP1 and a second operational amplifier OP2;

[0106] The non-inverting input of the first operational amplifier OP1 is connected to the output of the detector diode D through the seventh resistor R7, the inverting input of the first operational amplifier OP1 is connected to the ground through the eighth resistor R8, and the ninth resistor R9 is connected in series between the inverting input and the output of the first operational amplifier OP1.

[0107] The non-inverting input of the second operational amplifier OP2 is connected to the output of the first operational amplifier OP1 through the tenth resistor R10, the inverting input of the second operational amplifier OP2 is connected to its output, and the output of the second operational amplifier OP2 is connected to an external load through the eleventh resistor R11.

[0108] Specifically, in the embodiments of this utility model, referring to Figure 6 The low-frequency voltage signal output from the detector diode D is current-limited by the seventh resistor R7 and then input to the non-inverting input of the first operational amplifier OP1. The first operational amplifier OP1, together with the eighth resistor R8 and the ninth resistor R9, forms a non-inverting proportional amplifier circuit to initially amplify and condition the input signal. Its amplification factor is determined by the resistance ratio of the eighth resistor R8 to the ninth resistor R9. To ensure the stability of the operational amplifier's operation, capacitors C54 and C55 are connected in parallel between its positive power supply pin VCC and ground for power supply decoupling, effectively suppressing high-frequency noise on the power line.

[0109] The signal amplified by the first operational amplifier OP1 is coupled to the non-inverting input of the second operational amplifier OP2 through the tenth resistor R10. The second operational amplifier OP2 is configured as a voltage follower, with its inverting input directly shorted to its output, resulting in extremely high input impedance and extremely low output impedance. This structure achieves excellent impedance transformation and buffer isolation, enabling it to drive subsequent loads without affecting the performance of the preceding amplifier circuit. Finally, the conditioned signal is current-limited and output to the external load through the eleventh resistor R11, completing the entire process of conditioning, amplifying, and buffering the detected signal.

[0110] In a preferred embodiment of this utility model, the radio frequency signal transmission branch 4 further includes:

[0111] The first LC filter module 41 is connected between the third DC blocking capacitor C3 and the radio frequency amplifier RF;

[0112] Attenuation module 42 is connected between the first LC filter module 41 and the radio frequency amplifier RF;

[0113] The second LC filter module 43 is connected in parallel between the RF amplifier RF and the fourth DC blocking capacitor C50.

[0114] Specifically, in the embodiments of this utility model, referring to Figure 6 Even after the composite signal passes through the third DC blocking capacitor C3 to filter out the DC component, the resulting radio frequency (RF) signal may still carry out-of-band noise or harmonic interference. To ensure the purity of the signal input to the RF amplifier and prevent out-of-band noise from being amplified, this invention incorporates a first LC filter module 41 in the signal path. This first LC filter module 41 consists of an inductor L41 and capacitors C41 and C42 connected in parallel across it, forming a low-pass or band-pass filter network. Its function is to effectively filter out high-frequency noise and out-of-band noise in the RF signal, providing a clean input signal for subsequent amplification stages, thereby improving the signal-to-noise ratio and preventing interference signals from causing amplifier saturation.

[0115] To further optimize the signal dynamic range and prevent the RF amplifier from entering the nonlinear operating region or even distorting due to excessively strong input signals, an attenuation module 42 is introduced after the first LC filter module 41. This attenuation module 42 consists of a second resistor R2 and two resistors R1 and R3 connected in parallel across it, forming an adjustable π-type or T-type resistor attenuation network. This network is designed to adjust the attenuation rate and set the detection range, with a nominal attenuation of -6dBm. By selecting appropriate resistor values, this module can accurately attenuate the signal amplitude, adjusting the signal power to the optimal input level range of the RF amplifier without introducing additional nonlinear distortion. This protects the amplifier from overload damage and ensures amplification linearity.

[0116] After amplification, the output of the radio frequency (RF) signal inevitably generates new harmonic components and spurious noise introduced by the amplifier's nonlinearity, in addition to the required main frequency signal. To suppress these unwanted frequency components and purify the output spectrum, a grounded capacitor C45 is first connected in parallel at the output of the RF amplifier. This capacitor provides a low-impedance path to ground for the core high-frequency noise, initially filtering out some extremely high-frequency spurious interference. Based on this, a second LC filter module 43 is further connected in parallel. This second LC filter module 43 consists of inductors L42 and L43 and capacitors C46, ​​C47, C48, and C49, forming a multi-order LC filter network. Inductors L42 and L43 are connected in series in the main path, while capacitors C46, ​​C47, and C48 are connected in parallel between nodes, working together with C49 to form a high-performance low-pass or band-stop filter, effectively filtering out high-order harmonics and out-of-band noise generated by the amplifier. Finally, the filtered clean radio frequency signal is then blocked by the fourth DC blocking capacitor C50 before being output, which significantly improves the spectral purity and overall quality of the output signal and meets the system's high standard requirements for radio frequency signals.

[0117] Furthermore, considering that the signal processed by attenuation module 42 may still contain extremely high-frequency noise or interference introduced by distributed parameters when transmitted to the RF amplifier input, to ensure the signal quality of the final input amplifier, capacitor C43 is connected in series in the path between the output of attenuation module 42 and the RF amplifier input, and capacitor C44 is connected in parallel between this node and ground. Capacitor C43 acts as DC blocking and AC signal coupling, further blocking any DC offset that may exist in the preceding stage; while C44 provides a low-impedance path to ground for high-frequency interference signals, effectively bypassing residual high-frequency noise. C43 and C44 together form a simple high-pass or band-pass filter structure, working in conjunction with the aforementioned modules to perform final signal preprocessing, thereby providing a cleaner and more stable input environment for the RF amplifier, maximizing the amplifier's linear performance and operating efficiency.

[0118] Since the detected signal output by the detector diode D is typically a weak, non-standard level signal containing high-frequency residual components, direct processing is susceptible to interference and lacks accuracy. Therefore, a sixth resistor R6 is connected in series between the output of the detector diode D and the input of the seventh resistor R7. Simultaneously, at the node between diode D and the sixth resistor R6, capacitors C5, C52, and the fifth resistor R5 are connected in parallel in sequence, and capacitor C53 is connected in parallel between the sixth resistor R6 and the seventh resistor R7. The sixth resistor R6 primarily serves as a current limiter, protecting the subsequent conditioning circuit from excessive current surges. The parallel capacitors C5 and C52 efficiently filter out residual high-frequency carrier waves and harmonic components in the detected signal. The fifth resistor R5 provides a discharge path for the DC component and, in conjunction with the capacitors, adjusts the time constant to optimize response speed. Finally, the capacitor C53, connected in parallel between the sixth resistor R6 and the seventh resistor R7, further filters out noise that may couple between the two resistors, acting as a decoupling and signal smoothing agent. This network collectively performs preliminary shaping, filtering, and impedance matching on the raw signal after detection, significantly improving the signal-to-noise ratio and stability, and laying a reliable foundation for subsequent high-precision conditioning of the operational amplifier.

[0119] Reference Figure 6In the RF signal transmission branch 4, multiple current sources are distributed, namely I1, I2, I3, I4, and I5. Specifically, current source I1 is located between the third DC blocking capacitor C3 and the first LC filter module 41, providing a stable bias current for the filter network; I2 is located at the output of the first LC filter module 41, serving as impedance matching and signal buffering; I3 is located between the attenuation module 42 and capacitor C43, compensating for signal loss introduced by the attenuation network; I4 is located between capacitor C43 and the RF amplifier RF, providing a precise quiescent operating point for the amplifier input stage; and I5 is located between the RF amplifier RF and the fourth DC blocking capacitor C50, stabilizing the amplifier output level and improving load capacity. These current sources are sequentially distributed at key nodes in the signal path, collectively providing stable and precise bias for each stage of the circuit, ensuring high linearity and low noise performance of the RF signal during filtering, attenuation, amplification, and transmission, thereby guaranteeing the overall stability and signal processing accuracy of the branch.

[0120] In summary, this invention innovatively constructs a fusion system integrating power transmission and signal coverage by achieving the co-transmission of DC power supply and RF signals within a single RF feed line. The system integrates electrical signals using a feed-transmitter module, synchronously distributes composite signals through a feed branch distributor, and efficiently separates pure DC power and RF signals using a signal separation circuit integrated within the antenna. This provides stable power to the multi-functional antenna without requiring additional dedicated power lines. This solution not only significantly reduces the complexity and cost of system deployment but also effectively improves network flexibility and scalability, providing reliable technical support for modern indoor communication and IoT applications.

[0121] The above description is only a preferred embodiment of the present utility model and does not limit the implementation method and protection scope of the present utility model. Those skilled in the art should realize that all solutions obtained by equivalent substitutions and obvious changes made based on the description and illustrations of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A common transmission system based on an RF feeder, characterized in that, include: The power supply transmitter module (1) is integrated into the transmitter port of the fiber optic repeater remote unit (6). The integrated output terminal (13) of the power supply transmitter module (1) outputs a composite signal of radio frequency signal and DC power. A power supply branch distributor (2), the composite signal input terminal (21) of which is connected to the integrated output terminal (13) of the power supply transmitter module (1); The feed antenna (5) has a signal separation circuit integrated inside it. The input terminal (RF_IN) of the signal separation circuit is connected to the direct output terminal (22) or the coupled output terminal (23) of the feed branch distributor (2). The signal separation circuit includes a parallel DC regulated power supply branch (3) and a radio frequency signal transmission branch (4) to separate the received composite signal into DC and radio frequency signals.

2. The common transmission system based on radio frequency feeder according to claim 1, characterized in that, The radio frequency signal input terminal (11) of the power supply transmitter module (1) is connected to the transmitter port of the fiber optic repeater remote unit (6), and the DC input terminal (12) of the power supply transmitter module (1) is connected to an external DC power supply.

3. The common transmission system based on radio frequency feeder according to claim 2, characterized in that, The fed transmitting module (1) includes: The first DC blocking capacitor (C1) is connected between the radio frequency signal input terminal (11) and the integrated output terminal (13); A first radio frequency choke inductor (L1) is connected between the DC input terminal (12) and the integrated output terminal (13).

4. The common transmission system based on radio frequency feeder according to claim 1, characterized in that, The power supply branch distributor (2) includes: The second DC blocking capacitor (C2) has its first end connected to the second transmission line (25) and its second end connected to the ground terminal. A load resistor (R0) is connected between the second DC blocking capacitor (C2) and the ground terminal. One end of the second transmission line (25) is connected to the first transmission line (24), and the other end is connected to the coupling output terminal (23). The first transmission line (24) is connected between the composite signal input terminal (21) and the through output terminal (22). The second RF choke inductor (L2) has its first end connected to the first transmission line (24) and its second end connected to the second transmission line (25).

5. A common transmission system based on an RF feeder according to claim 1, characterized in that, The DC regulated power supply branch (3) includes: The third RF choke inductor (L3) has its first terminal connected to the input terminal (RF_IN) of the signal separation circuit; The first voltage regulator chip (U1) has its input terminal connected to the second terminal of the third RF choke inductor (L3), and its output terminal outputs a first DC voltage. The second voltage regulator chip (U2) has its input terminal connected to the output terminal of the first voltage regulator chip (U1), and its output terminal outputs a second DC voltage. A current-limiting resistor (R) is connected in series between the first voltage regulator chip (U1) and the second voltage regulator chip (U2) to limit the current flowing through the second voltage regulator chip (U2).

6. A common transmission system based on an RF feeder according to claim 5, characterized in that, The DC regulated power supply branch (3) also includes multiple filter networks, which are connected in parallel to each node of the DC regulated power supply branch (3) to filter out voltage ripple at different nodes.

7. A common transmission system based on an RF feeder according to claim 6, characterized in that, The filtering network includes: The first filtering network includes a first filtering capacitor (C31) and a second filtering capacitor (C32), which are connected in parallel between the third RF choke inductor (L3) and the first voltage regulator chip (U1). The second filter network includes a third filter capacitor (C33) and a fourth filter capacitor (C34), which are connected in parallel between the first voltage regulator chip (U1) and the current limiting resistor (R). The third filtering network includes a fifth filtering capacitor (C35) and a sixth filtering capacitor (C36), which are connected in parallel between the current limiting resistor (R) and the second voltage regulator chip (U2). The fourth filter network includes a seventh filter capacitor (C37) and an eighth filter capacitor (C38), which are connected in parallel between the second voltage regulator chip (U2) and the load.

8. A common transmission system based on an RF feeder according to claim 1, characterized in that, The radio frequency signal transmission branch (4) includes: The third DC blocking capacitor (C3) has its first terminal connected to the input terminal (RF_IN) of the signal separation circuit; A radio frequency (RF) amplifier, the input of which is connected to the second terminal of the third DC blocking capacitor (C3); The fourth DC blocking capacitor (C50) has its first terminal connected to the output terminal of the radio frequency amplifier (RF). A detector diode (D), the input terminal of which is connected to the second terminal of the fourth DC blocking capacitor (C50); The signal conditioning and output buffer module (44) is connected to the output terminal of the detector diode (D).

9. A common transmission system based on an RF feeder according to claim 8, characterized in that, The signal conditioning and output buffer module (44) includes a first operational amplifier (OP1) and a second operational amplifier (OP2); The non-inverting input of the first operational amplifier (OP1) is connected to the output of the detector diode (D) through the seventh resistor (R7), the inverting input of the first operational amplifier (OP1) is connected to the ground through the eighth resistor (R8), and a ninth resistor (R9) is connected in series between the inverting input and the output of the first operational amplifier (OP1). The non-inverting input of the second operational amplifier (OP2) is connected to the output of the first operational amplifier (OP1) through the tenth resistor (R10), the inverting input of the second operational amplifier (OP2) is connected to its output, and the output of the second operational amplifier (OP2) is connected to an external load through the eleventh resistor (R11).

10. A common transmission system based on an RF feeder according to claim 8, characterized in that, The radio frequency signal transmission branch (4) also includes: The first LC filter module (41) is connected between the third DC blocking capacitor (C3) and the radio frequency amplifier (RF); An attenuation module (42) is connected between the first LC filter module (41) and the radio frequency amplifier (RF); The second LC filter module (43) is connected in parallel between the radio frequency amplifier (RF) and the fourth DC blocking capacitor (C50).

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