A dual-path MIMO room division network system and a dual-path signal transceiving method

Abstract

This invention provides a dual-channel MIMO indoor distributed network system and a dual-channel signal transceiver method. In the downlink direction, a first RRU converts the signal transmitted by the BBU into a first radio frequency (RF) signal and a first intermediate frequency (IF) signal to generate a local oscillator (LOS) signal; it outputs power; a frequency combiner combines the signal and power supply into a first signal; an antenna separates the first signal; a power-powered active mixer converts the first IF signal into a second RF signal; a power amplifier amplifies the signal power; the first RF signal and the second RF signal are transmitted; in the uplink direction, a third RF signal and a fourth RF signal are received; a power-powered low-noise amplifier amplifies the signal, converting the third RF signal into a second IF signal; the signals are combined into a second signal; a frequency combiner separates the second signal; and the first RRU converts the signal into a baseband signal and transmits it to the BBU. The solution provided by this invention can reduce the construction cost of an indoor distributed network system.

Description

Technical Field

[0001] This invention relates to the field of communication technology, and in particular to a dual-channel MIMO indoor distribution network system and a dual-channel signal transceiver method. Background Technology

[0002] In real-world applications, most mobile communication services occur indoors. To ensure the quality of mobile communication for terminals indoors, it is necessary to build an indoor distributed network system to achieve indoor signal coverage. Furthermore, to increase data capacity, the indoor distributed network system can be configured as a dual-path MIMO (Multiple-in Multiple-out) system.

[0003] In existing dual-channel MIMO indoor distribution network systems, the Remote Radio Unit (RRU) transmits two radio frequency (RF) signals with the same frequency. The RRU shifts one RF signal to an intermediate frequency (IF) signal and sends this IF signal, a local oscillator (LO) signal matching the IF signal, and the other RF signal to a frequency combiner. The frequency combiner combines the RF signal, IF signal, and LO signal into a single signal and transmits this single signal to the antenna. The antenna performs frequency separation processing on this single signal to reconstruct the RF signal, IF signal, and LO signal. Based on the LO signal, it performs frequency conversion processing on the IF signal to restore the IF signal to the RF signal. The antenna then transmits both RF signals to achieve indoor signal coverage.

[0004] Because the power of the signal output by the RRU gradually decreases during transmission to the antenna, the RRU needs to output a high-power signal in order to ensure that the signal transmitted by the antenna has sufficient power. However, outputting a high-power signal requires the use of expensive devices that support high-power output, which results in the high construction cost of existing dual-channel MIMO indoor distribution network systems. Summary of the Invention

[0005] The purpose of this invention is to provide a dual-channel MIMO indoor distributed network system and a dual-channel signal transceiver method, so as to reduce the construction cost of the dual-channel MIMO indoor distributed network system. The specific technical solution is as follows:

[0006] In a first aspect, embodiments of the present invention provide a dual-channel MIMO indoor distribution network system, the indoor distribution network system including a baseband processing unit (BBU), a first radio frequency pull unit (RRU), a frequency combiner, a signal transmission link, and an antenna, wherein the antenna is an active frequency conversion dual-polarized antenna, and the antenna includes: a power amplifier, a low-noise amplifier, a multiplexer, and an active mixer;

[0007] The BBU is used to send downlink baseband modulation signals to the first RRU, wherein each set of downlink baseband modulation signals contains two signals.

[0008] The first RRU is used to convert two signals contained in a set of downlink baseband modulation signals into a first radio frequency signal and a first intermediate frequency signal respectively in the downlink direction, and generate a local oscillator signal for frequency conversion of the first intermediate frequency signal; output a power supply to send the first radio frequency signal, the first intermediate frequency signal, the local oscillator signal and the power supply to the frequency combiner.

[0009] The frequency combiner is used to combine the first intermediate frequency signal, local oscillator signal, first radio frequency signal and power supply from the first RRU in the downlink direction to obtain a first signal; and transmit the first signal to the antenna through the signal transmission link.

[0010] The antenna is used to separate the first signal in the downlink direction using a multiplexer to obtain a first intermediate frequency signal, a local oscillator signal, a first radio frequency signal, and a power supply; to power an active mixer with the power supply, and to convert the first intermediate frequency signal into a second radio frequency signal based on the local oscillator signal using the active mixer; to power a power amplifier with the power supply, and to amplify the first radio frequency signal and the second radio frequency signal using the power amplifier; and to transmit the amplified first radio frequency signal and the second radio frequency signal respectively, wherein the first radio frequency signal and the second radio frequency signal have the same frequency.

[0011] The antenna is also used to receive a third radio frequency signal and a fourth radio frequency signal transmitted by the terminal in the uplink direction; to power a low-noise amplifier with a power supply, and to amplify the third radio frequency signal and the fourth radio frequency signal through the low-noise amplifier; to power an active mixer with a power supply, and to convert the amplified third radio frequency signal into a second intermediate frequency signal based on the local oscillator signal through the active mixer; to perform signal combining processing on the second intermediate frequency signal and the fourth radio frequency signal through a multiplexer to obtain a second signal; and to send the second signal to the frequency combiner through a signal transmission link.

[0012] The frequency combiner is also used to separate the second signal from the antenna into a fourth radio frequency signal and a second intermediate frequency signal in the uplink direction, and send the fourth radio frequency signal and the second intermediate frequency signal to the first RRU.

[0013] The first RRU is also used to convert the fourth radio frequency signal and the second intermediate frequency signal into two uplink baseband modulation signals in the uplink direction, and send the two uplink baseband modulation signals to the BBU.

[0014] Secondly, embodiments of the present invention provide a dual-channel signal transceiver method applied to an indoor distributed network system. The indoor distributed network system includes a baseband processing unit (BBU), a first radio frequency pull unit (RRU), a frequency combiner, a signal transmission link, and an antenna. The antenna is an active frequency conversion dual-polarized antenna and includes a power amplifier, a low-noise amplifier, a multiplexer, and an active mixer.

[0015] The BBU sends downlink baseband modulation signals to the first RRU, wherein each set of downlink baseband modulation signals contains two signals.

[0016] In the downlink direction, the first RRU converts two signals contained in a set of downlink baseband modulation signals into a first radio frequency signal and a first intermediate frequency signal, respectively, and generates a local oscillator signal for frequency conversion of the first intermediate frequency signal;

[0017] The first RRU outputs a power supply to send the first radio frequency signal, the first intermediate frequency signal, the local oscillator signal and the power supply to the frequency combiner.

[0018] In the downlink direction, the first intermediate frequency signal, local oscillator signal, first radio frequency signal and power supply from the first RRU are combined by a frequency combiner to obtain a first signal.

[0019] The first signal is transmitted from the frequency combiner to the antenna via a signal transmission link;

[0020] In the downlink direction, the first signal is separated by a multiplexer through an antenna to obtain a first intermediate frequency signal, a local oscillator signal, a first radio frequency signal, and a power supply. The power supply powers an active mixer, which converts the first intermediate frequency signal into a second radio frequency signal based on the local oscillator signal. The power supply powers a power amplifier, which amplifies the first and second radio frequency signals. The first and second radio frequency signals have the same frequency.

[0021] The first and second radio frequency signals, after being amplified by power, are transmitted through the antenna, respectively.

[0022] The antenna receives the third and fourth radio frequency signals transmitted by the terminal in the uplink direction. The power supply powers the low noise amplifier, which amplifies the third and fourth radio frequency signals. The power supply powers the active mixer, which converts the amplified third radio frequency signal into a second intermediate frequency signal based on the local oscillator signal. The multiplexer performs signal combining on the second intermediate frequency signal and the fourth radio frequency signal to obtain the second signal.

[0023] A second signal is transmitted from the antenna to the frequency combiner via a signal transmission link;

[0024] In the uplink direction, the second signal from the antenna is separated into a fourth radio frequency signal and a second intermediate frequency signal by a frequency combiner, and the fourth radio frequency signal and the second intermediate frequency signal are sent to the first RRU.

[0025] The first RRU converts the fourth radio frequency signal and the second intermediate frequency signal into two uplink baseband modulation signals in the uplink direction, and sends the two uplink baseband modulation signals to the BBU.

[0026] Beneficial effects of the embodiments of the present invention:

[0027] This invention provides a dual-MIMO indoor distributed antenna system. The antenna in this system can transmit at least two radio frequency (RF) signals with the same frequency, meaning the system supports dual-MIMO functionality. Furthermore, in this system, the signal transmitted by the first remote root unit (RRU) to the antenna via a frequency combiner includes a current source. This current allows the first RRU to power the antenna, making it an active antenna. This enables the antenna to use an active mixer (which operates only when powered) to convert the first intermediate frequency (IF) signal to a second RF signal based on the local oscillator signal. The antenna can also use a power amplifier (which operates only when powered) to amplify the power of the first and second RF signals, allowing it to transmit high-power signals. Therefore, the antenna in this indoor distributed antenna system can amplify the transmitted signal itself, ensuring a high-power signal. The first RRU does not need to transmit a high-power signal to the antenna, thus eliminating the need for expensive high-power output devices in the first RRU and reducing the overall cost of the indoor distributed antenna system.

[0028] Furthermore, after receiving the third and fourth radio frequency signals, the antenna can use a low-noise amplifier, which can only be used when powered on, to amplify the third and fourth radio frequency signals. This allows the dual-channel MIMO indoor distribution network system provided in this embodiment of the invention to also improve the power of the received third and fourth radio frequency signals without requiring the terminal to transmit a high-power signal. The dual-channel MIMO indoor distribution network system provided in this embodiment of the invention can also ensure the power of the uplink signal reported by the terminal.

[0029] Furthermore, in the solution provided by the embodiments of the present invention, the power supply for the antenna is uniformly provided by the first RRU. When there are many antennas in the indoor distributed network system, it is not necessary to configure a separate power supply for each antenna. This makes the structure of the indoor distributed network system provided by the embodiments of the present invention relatively simple and easy to configure. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0031] Figure 1 This is a schematic diagram of the structure of the first dual-path MIMO indoor distribution network system provided in an embodiment of the present invention;

[0032] Figure 2 This is a schematic diagram of the structure of a first RRU and a frequency combiner provided in an embodiment of the present invention;

[0033] Figure 3 This is a schematic diagram of the structure of the first type of antenna provided in an embodiment of the present invention;

[0034] Figure 4 This is a schematic diagram of the structure of the second type of first RRU and frequency combiner provided in an embodiment of the present invention;

[0035] Figure 5 This is a schematic diagram of the structure of a second type of antenna provided in an embodiment of the present invention;

[0036] Figure 6 A schematic diagram of a coupler provided in an embodiment of the present invention;

[0037] Figure 7 This is a schematic diagram of a coupler and antenna provided in an embodiment of the present invention;

[0038] Figure 8 This is a schematic diagram of the structure of a second type of dual-path MIMO indoor distribution network system provided in an embodiment of the present invention;

[0039] Figure 9 This is a schematic diagram of the structure of a third type of dual-path MIMO indoor distribution network system provided in an embodiment of the present invention;

[0040] Figure 10 This is a schematic diagram of the structure of the fourth dual-path MIMO indoor distribution network system provided in the embodiments of the present invention;

[0041] Figure 11 This is a schematic diagram of the structure of a third type of antenna provided in an embodiment of the present invention;

[0042] Figure 12 This is a flowchart illustrating a dual-channel signal transceiver method provided in an embodiment of the present invention. Detailed Implementation

[0043] In this embodiment of the invention, the term "and / or" describes the relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. The character " / " generally indicates that the preceding and following associated objects have an "or" relationship.

[0044] In this embodiment of the invention, the term "multiple" refers to two or more, and other quantifiers are similar.

[0045] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art based on the embodiments of the present invention are within the scope of protection of the present invention.

[0046] To reduce the construction cost of a dual-channel MIMO indoor distribution network system, this invention provides a dual-channel MIMO indoor distribution network system and a dual-channel signal transceiver method.

[0047] A dual-channel MIMO indoor distribution network system, the indoor distribution network system includes a BBU (Building Baseband Unit), a first RRU, a frequency combiner, a signal transmission link and an antenna, the antenna being an active frequency conversion dual-polarized antenna, the antenna including: a power amplifier, a low-noise amplifier, a multiplexer, and an active mixer.

[0048] The aforementioned BBU is used to send downlink baseband modulation signals to the first RRU, wherein each set of downlink baseband modulation signals contains two signals.

[0049] The aforementioned first RRU is used to convert two signals contained in a set of downlink baseband modulation signals into a first radio frequency signal and a first intermediate frequency signal respectively in the downlink direction, and generate a local oscillator signal for frequency conversion of the first intermediate frequency signal; output a power supply to send the aforementioned first radio frequency signal, first intermediate frequency signal, local oscillator signal and power supply to the frequency combiner.

[0050] The aforementioned frequency combiner is used to perform signal combining processing on the first intermediate frequency signal, local oscillator signal, first radio frequency signal and power supply from the first RRU in the downlink direction to obtain a first signal; and to transmit the aforementioned first signal to the antenna through the signal transmission link.

[0051] The antenna described above is used to separate the first signal in the downlink direction using a multiplexer to obtain a first intermediate frequency signal, a local oscillator signal, a first radio frequency signal, and a power supply; to power an active mixer with the power supply, and to convert the first intermediate frequency signal into a second radio frequency signal based on the local oscillator signal using the active mixer; to power a power amplifier with the power supply, and to amplify the first radio frequency signal and the second radio frequency signal using the power amplifier; and to transmit the amplified first radio frequency signal and the second radio frequency signal respectively, wherein the first radio frequency signal and the second radio frequency signal have the same frequency.

[0052] The aforementioned antenna is also used to receive the third and fourth radio frequency signals transmitted by the terminal in the uplink direction; to power a low-noise amplifier, which amplifies the third and fourth radio frequency signals; to power an active mixer, which converts the amplified third radio frequency signal into a second intermediate frequency signal based on the local oscillator signal; to combine the second intermediate frequency signal and the fourth radio frequency signal using a multiplexer to obtain a second signal; and to send the second signal to the frequency combiner via a signal transmission link.

[0053] The aforementioned frequency combiner is also used to separate the second signal from the antenna into a fourth radio frequency signal and a second intermediate frequency signal in the uplink direction, and send the fourth radio frequency signal and the second intermediate frequency signal to the first RRU.

[0054] The aforementioned first RRU is also used to convert the fourth radio frequency signal and the second intermediate frequency signal into two uplink baseband modulation signals in the uplink direction, and send the two uplink baseband modulation signals to the BBU.

[0055] As can be seen from the above, the embodiments of the present invention provide a dual-channel MIMO indoor distributed network system. The antennas included in this system can transmit at least two radio frequency signals with the same frequency, meaning the system supports dual-channel MIMO functionality. Furthermore, in this system, the signal transmitted by the first RRU to the antenna via a frequency combiner includes a power supply, meaning the first RRU can power the antenna through this supply. This indicates the antenna in the system is an active antenna, enabling it to use an active mixer (which operates only when powered) to convert the first intermediate frequency signal to a second radio frequency signal based on the local oscillator signal. The antenna can also use a power amplifier (which operates only when powered) to amplify the power of the first and second radio frequency signals, allowing it to transmit high-power signals. Therefore, the antenna in the indoor distributed network system provided by the embodiments of the present invention can amplify the transmitted signal itself, ensuring a high-power signal. The first RRU does not need to transmit a high-power signal to the antenna, thus eliminating the need for expensive high-power output devices in the first RRU, thereby reducing the cost of the indoor distributed network system.

[0056] Furthermore, after receiving the third and fourth radio frequency signals, the antenna can use a low-noise amplifier, which can only be used when powered on, to amplify the third and fourth radio frequency signals. This allows the dual-channel MIMO indoor distribution network system provided in this embodiment of the invention to also improve the power of the received third and fourth radio frequency signals without requiring the terminal to transmit a high-power signal. The dual-channel MIMO indoor distribution network system provided in this embodiment of the invention can also ensure the power of the uplink signal reported by the terminal.

[0057] Furthermore, in the solution provided by this embodiment of the invention, the antenna power supply is uniformly provided by the first RRU. When the indoor distributed antenna system contains a large number of antennas, it is not necessary to configure a separate power supply for each antenna, making the structure of the indoor distributed antenna system provided by this embodiment of the invention simpler and easier to configure. In addition, the first RRU can flexibly choose to turn off the power supply, and can directly turn off the power supply of all antennas in the indoor distributed antenna system, thereby achieving energy saving of the indoor distributed antenna system.

[0058] See Figure 1 This is a schematic diagram of the structure of a first dual-path MIMO indoor distribution network system provided in an embodiment of the present invention. The indoor distribution network system includes a BBU 101, a first RRU 102, a frequency combiner 103, a signal transmission link 104, and an antenna 105. The antenna 105 is an active frequency conversion dual-polarized antenna and includes a power amplifier, a low-noise amplifier, a multiplexer, and an active mixer.

[0059] The aforementioned BBU101 is used to send downlink baseband modulation signals to the first RRU102.

[0060] Each set of downlink baseband modulation signals contains two signals.

[0061] The aforementioned first RRU102 is used to convert two signals contained in a set of downlink baseband modulation signals into a first radio frequency signal and a first intermediate frequency signal respectively in the downlink direction, and generate a local oscillator signal for frequency conversion of the first intermediate frequency signal; output a power supply to send the aforementioned first radio frequency signal, first intermediate frequency signal, local oscillator signal and power supply to the frequency combiner.

[0062] Specifically, the first RRU102 is connected to the BBU101, receives two downlink baseband modulation signals sent by the BBU101, converts one downlink baseband signal into a high-frequency first radio frequency signal, shifts the other downlink baseband signal to an intermediate frequency (IF) signal, and generates a local oscillator signal for frequency conversion of the IF signal. The frequencies of the first radio frequency signal, the first IF signal, and the local oscillator signal are all different.

[0063] For example, the frequency of the first radio frequency signal mentioned above can be 2.6 GHz.

[0064] Specifically, the first RRU102 includes a digital intermediate frequency signal processor, which is used to receive two downlink baseband modulation signals sent by BBU101 and send the two downlink baseband modulation signals to the transceiver. The transceiver converts the downlink baseband modulation signals into a first radio frequency signal, a first intermediate frequency signal and generates a local oscillator signal.

[0065] In addition, the power supply mentioned above can be regarded as a DC signal; for example, the power supply can be a 12V power supply.

[0066] In addition, the first RRU102 may also include a power amplifier. The first RRU102 first amplifies the first radio frequency signal, the first intermediate frequency signal and the local oscillator signal through the power amplifier, and then the frequency combiner 103 sends the amplified first radio frequency signal, the first intermediate frequency signal and the local oscillator signal.

[0067] The aforementioned frequency combiner 103 is used to perform signal combining processing on the first intermediate frequency signal, local oscillator signal, first radio frequency signal and power supply from the first RRU 102 in the downlink direction to obtain a first signal; and to send the aforementioned first signal to the antenna 105 through the signal transmission link 104.

[0068] Specifically, the aforementioned frequency combiner 103 can combine the first radio frequency signal, the first intermediate frequency signal, and the local oscillator signal into a single signal. The frequency combiner also includes an inductor and capacitor for power supply. The frequency combiner 103 inputs a power supply received from the first RRU 102 into the inductor and capacitor, and then fuses this power supply with a signal generated based on the first radio frequency signal, the first intermediate frequency signal, and the local oscillator signal through the inductor and capacitor to obtain a first signal.

[0069] The common antenna port of the aforementioned frequency combiner 103 is connected to the aforementioned signal transmission link 104, and the generated first signal is transmitted to the signal transmission link through the aforementioned common antenna port.

[0070] Specifically, the aforementioned signal transmission link 104 can be a single link or contain multiple different links.

[0071] In the case where the signal transmission link 104 includes multiple different links, the signal transmission link 104 may include a power divider to separate the received first signal into multiple different signals, which are then transmitted to antennas 105 connected to different links. Specifically, the number of different signals obtained is the same as the number of links included in the signal transmission link 104.

[0072] In one embodiment, the structure of the first RRU102 and the frequency combiner 103 described above can be seen below. Figure 2 The embodiments shown are not described in detail here.

[0073] The antenna 105 is used to separate the first signal in the downlink direction using a multiplexer to obtain a first intermediate frequency signal, a local oscillator signal, a first radio frequency signal, and a power supply; to power an active mixer with the power supply, and to convert the first intermediate frequency signal into a second radio frequency signal based on the local oscillator signal using the active mixer; to power a power amplifier with the power supply, and to amplify the first radio frequency signal and the second radio frequency signal using the power amplifier; and to transmit the amplified first radio frequency signal and the second radio frequency signal respectively.

[0074] The first radio frequency signal and the second radio frequency signal have the same frequency.

[0075] Specifically, the multiplexer includes an inductor, which separates one power supply from the first signal. Then, the first signal after the power supply is separated is further divided into a first radio frequency signal, a first intermediate frequency signal, and a local oscillator signal with different powers.

[0076] The antenna 105 may also include a DC power converter, which converts the separated power supply into a more stable power supply to power the devices contained in the antenna 105. The converted power supply can be a 5V power supply.

[0077] The first intermediate frequency signal and the local oscillator signal are input into an active mixer. The active mixer converts the first intermediate frequency signal into a second radio frequency signal with the same frequency as the first radio frequency signal based on the local oscillator signal. The active mixer may include a power amplifier, which can amplify the power of the local oscillator signal to ensure that the local oscillator signal has a large power. Then, based on the power-amplified local oscillator signal, the first intermediate frequency signal is converted into the second radio frequency signal, resulting in a better frequency conversion effect.

[0078] In this embodiment of the invention, the antenna 105 may include two different power amplifiers, which are used to amplify the power of the first radio frequency signal and the second radio frequency signal, respectively.

[0079] In addition, the antenna 105 may also include an attenuator. Before the first radio frequency signal and the second radio frequency signal are input into the power amplifier, the first radio frequency signal and the second radio frequency signal can be input into the attenuator for attenuation processing, and then the attenuated first radio frequency signal and the second radio frequency signal can be input into the power amplifier.

[0080] Furthermore, the antenna 105 may also include a filter, into which the amplified first and second radio frequency signals are input for filtering and processing before transmission.

[0081] The antenna 105 may include a dual-polarized antenna array, which contains two different arrays that transmit a first radio frequency signal and a second radio frequency signal respectively.

[0082] In one embodiment, the structure of the antenna 105 described above can be seen below. Figure 3 The embodiments shown are not described in detail here.

[0083] Specifically, the foregoing content describes the signal processing process performed by the dual-channel MIMO indoor distribution network system in the downlink direction when transmitting signals to the terminal. Next, the process of the dual-channel MIMO indoor distribution network system processing the received signals after receiving the signals transmitted by the terminal in the uplink direction will be described.

[0084] The antenna 105 described above is also used to receive a third radio frequency signal and a fourth radio frequency signal transmitted by the terminal in the uplink direction; to power a low-noise amplifier with a power supply, and to amplify the third radio frequency signal and the fourth radio frequency signal through the low-noise amplifier; to power an active mixer with a power supply, and to convert the amplified third radio frequency signal into a second intermediate frequency signal based on the local oscillator signal through the active mixer; to perform signal combining processing on the second intermediate frequency signal and the fourth radio frequency signal through a multiplexer to obtain a second signal; and to send the second signal to the frequency combiner 103 through the signal transmission link 104.

[0085] Specifically, the antenna 105 described above can receive a third radio frequency signal and a fourth radio frequency signal respectively through two different elements contained in the dual-polarized antenna array. For example, the noise figures of the third and fourth radio frequency signals received by the antenna 105 are <3dB.

[0086] The antenna 105 may contain two different low-noise amplifiers, which are used to amplify the third radio frequency signal and the fourth radio frequency signal, respectively.

[0087] In addition, the antenna 105 may also include an attenuator, which is used to attenuate the amplified third radio frequency signal and the fourth radio frequency signal respectively. The fourth radio frequency signal output by the attenuator is then directly input into the multiplexer, and the third radio frequency signal is input into the active mixer. The active mixer converts the third radio frequency signal into a second intermediate frequency signal, and then the second intermediate frequency signal is input into the multiplexer.

[0088] After receiving the second intermediate frequency signal and the fourth radio frequency signal, the multiplexer performs signal combining on the second intermediate frequency signal and the fourth radio frequency signal to obtain the second signal.

[0089] The aforementioned frequency combiner 103 is also used to separate the second signal from the antenna into a fourth radio frequency signal and a second intermediate frequency signal in the uplink direction, and send the fourth radio frequency signal and the second intermediate frequency signal to the first RRU 102.

[0090] The aforementioned first RRU102 is also used to convert the fourth radio frequency signal and the second intermediate frequency signal into two uplink baseband modulation signals in the uplink direction, and send the two uplink baseband modulation signals to BBU101.

[0091] Specifically, the transceiver included in the first RRU102 can convert the received fourth radio frequency signal and second intermediate frequency signal into two uplink baseband modulation signals, and send the two uplink baseband modulation signals to the digital intermediate frequency processor, which then sends the two uplink baseband modulation signals to the BBU.

[0092] In addition, the first RRU102 may also include a low-noise amplifier to amplify the fourth radio frequency signal and the second intermediate frequency signal after receiving them. Furthermore, the first RRU102 may also include a filter for filtering the fourth radio frequency signal and the second intermediate frequency signal.

[0093] As can be seen from the above, the embodiments of the present invention provide a dual-channel MIMO indoor distributed network system. The antennas included in this system can transmit at least two radio frequency signals with the same frequency, meaning the system supports dual-channel MIMO functionality. Furthermore, in this system, the signal transmitted by the first RRU to the antenna via a frequency combiner includes a power supply, meaning the first RRU can power the antenna through this supply. This indicates the antenna in the system is an active antenna, enabling it to use an active mixer (which operates only when powered) to convert the first intermediate frequency signal to a second radio frequency signal based on the local oscillator signal. The antenna can also use a power amplifier (which operates only when powered) to amplify the power of the first and second radio frequency signals, allowing it to transmit high-power signals. Therefore, the antenna in the indoor distributed network system provided by the embodiments of the present invention can amplify the transmitted signal itself, ensuring a high-power signal. The first RRU does not need to transmit a high-power signal to the antenna, thus eliminating the need for expensive high-power output devices in the first RRU, thereby reducing the cost of the indoor distributed network system.

[0094] Furthermore, after receiving the third and fourth radio frequency signals, the antenna can use a low-noise amplifier, which can only be used when powered on, to amplify the third and fourth radio frequency signals. This allows the dual-channel MIMO indoor distribution network system provided in this embodiment of the invention to also improve the power of the received third and fourth radio frequency signals without requiring the terminal to transmit a high-power signal. The dual-channel MIMO indoor distribution network system provided in this embodiment of the invention can also ensure the power of the uplink signal reported by the terminal.

[0095] Furthermore, in the solution provided by this embodiment of the invention, the antenna power supply is uniformly provided by the first RRU. When the indoor distributed antenna system contains a large number of antennas, it is not necessary to configure a separate power supply for each antenna, making the structure of the indoor distributed antenna system provided by this embodiment of the invention simpler and easier to configure. In addition, the first RRU can flexibly choose to turn off the power supply, and can directly turn off the power supply of all antennas in the indoor distributed antenna system, thereby achieving energy saving of the indoor distributed antenna system.

[0096] Furthermore, since both RF signals are amplified by power amplifiers in the downlink direction, the RF performance of the two RF signals is relatively balanced, and the gains of the two dual-polarized elements are also the same. Therefore, the MIMO effect of the entire dual-channel MIMO indoor distribution network system can achieve a relatively ideal signal transmission effect.

[0097] In one embodiment of the present invention, the first RRU 102 and the frequency combiner 103 can be configured in the same device, in which case the housing of the device may contain only one output interface for outputting the first signal processed by the frequency combiner 103. Alternatively, the first RRU 102 and the frequency combiner 103 may be configured in two different devices, in which case the housing of the first RRU 102 may contain multiple different output interfaces for outputting the first radio frequency signal, the first intermediate frequency signal, the local oscillator signal, and the power supply, respectively.

[0098] See Figure 2 This is a schematic diagram of the structure of the first RRU and the frequency combiner provided in the embodiment of the present invention.

[0099] The part enclosed by the rectangular dashed box in the figure is the first RRU102, and the rest is the frequency combiner 103.

[0100] The aforementioned first RRU102 includes a digital intermediate frequency processor 102A, a transceiver 102B, a filter 102C, a power amplifier 102D, a low-noise amplifier 102E, a radio frequency channel 102F, an intermediate frequency channel 102G, a local oscillator channel 102H, and a power supply channel 102I. The functions of the digital intermediate frequency processor 102A, transceiver 102B, filter 102C, power amplifier 102D, and low-noise amplifier 102E are described above and will not be detailed here.

[0101] The aforementioned radio frequency channel 102F includes two channels, which are used to transmit the first radio frequency signal and the fourth radio frequency signal, respectively. The intermediate frequency channel 102G includes two channels, which are used to transmit the first intermediate frequency signal and the second intermediate frequency signal, respectively. The local oscillator channel 102H is a unidirectional channel used to transmit the local oscillator signal. The power supply channel 102I is a unidirectional channel used to transmit power.

[0102] The aforementioned frequency combiner 103 includes two duplexers 103A, a filter 103B, and an inductor and capacitor 103C for power supply, outlined in an elliptical dashed box.

[0103] Each of the two duplexers 103A contains two different filters. The two filters in the duplexer 103A connected to the RF channel 102F are used to process the first RF signal and the fourth RF signal, respectively. The two filters in the duplexer 103A connected to the IF channel 102G are used to process the first IF signal and the second IF signal, respectively. Filter 103B is used to process the local oscillator signal. The two duplexers 103A and filter 103B can be considered as three different channels in the frequency combiner 103. After processing their respective signals, the three channels can produce a single first signal.

[0104] See Figure 3 This is a schematic diagram of the structure of the first type of antenna provided in an embodiment of the present invention.

[0105] Specifically, the first signal input to the antenna includes RF1 (Radio Frequency), IF (Intermediate Frequency), LO (Local Oscillator), and Vcc (Volt Current Condenser). RF1 represents the first radio frequency signal, IF represents the first intermediate frequency signal, LO represents the local oscillator signal, Vcc represents the power supply, and Vcc2 represents the power supply after power conversion.

[0106] The antenna 105 includes a multiplexer 105A (defined by a rectangular dashed box), an inductor 105A1 (defined by an elliptical dashed box), and three filters 105A2 for processing the first radio frequency signal, the first intermediate frequency signal, and the local oscillator signal, respectively. The antenna 105 also includes a duplexer 105B, an active mixer 105C, a power amplifier 105D, a low-noise amplifier 105E, an attenuator 105F, a dual-polarized antenna array 105H, and a DC-DC converter 105I.

[0107] The triangle contained in the active mixer 105C represents a power amplifier.

[0108] As shown in the figure, the multiplexer 105A separates IF, LO, Vcc and RF1 and inputs them into different processing links. Specifically, IF and LO are input to the active mixer 105C, Vcc is input to the DC power converter 105I, and RF1 is input to the attenuator after passing through the switch 105B.

[0109] The functions of the multiplexer 105A, active mixer 105C, power amplifier 105D, low-noise amplifier 105E, attenuator 105F, dual-polarized antenna array 105H, and DC power converter 105I can be found in the previous description and will not be repeated here.

[0110] In the RF1 processing link, the duplexer 105B connected to the dual-polarized antenna array 105H contains two filters for combining the uplink and downlink RF frequencies into one path. The duplexer 105B connected to the multiplexer 105A contains two filters for separating the uplink and downlink RF frequencies into two paths.

[0111] The duplexer 105B connected to the dual-polarized antenna array 105H in the IF processing link contains two filters for combining the uplink and downlink intermediate frequency into one path. The duplexer 105B connected to the active mixer 105C contains two filters for separating the uplink and downlink intermediate frequency into two paths.

[0112] In another embodiment of the present invention, when the above-mentioned dual-channel MIMO indoor distribution network system performs signal processing based on the TDD (Time Division Duplexing) standard, the antenna also includes a detector. Specifically, the detector is configured in the antenna 105.

[0113] The aforementioned first RRU102 is specifically used to output a transmit / receive control signal in the downlink direction, and to modulate the transmit / receive control signal based on a preset carrier, and to send a first radio frequency signal, a first intermediate frequency signal, a local oscillator signal, a modulated transmit / receive control signal and a power supply to the frequency combiner 103.

[0114] The aforementioned transmit / receive control signal is used to control the antenna 105 to switch between transmit signal state and receive signal state. The level of the transmit / receive control signal when the antenna 105 switches to transmit signal state is different from the level of the transmit / receive control signal when the antenna 105 switches to receive signal state, so that the antenna 105 can switch between transmit signal state and receive signal state when it receives transmit / receive control signals of different levels.

[0115] For example, if the transmit / receive control signal received by antenna 105 is high, the system switches to transmit signal mode; if the transmit / receive control signal received by antenna 105 is low, the system switches to receive signal mode. Alternatively, if the transmit / receive control signal received by antenna 105 is high, the system switches to receive signal mode; if the transmit / receive control signal received by antenna 105 is low, the system switches to transmit signal mode. For example, the high level could be 5V and the low level could be 0V.

[0116] Specifically, the aforementioned transmit / receive control signal can be modulated into a sine wave signal based on a preset carrier. For example, the preset carrier can be an 800MHz carrier, then the transmit / receive control signal is an 800MHz sine wave signal. When the 800MHz sine wave is output, it is in the transmit signal state, and when the 800MHz sine wave is turned off, it is in the receive signal state.

[0117] The original transmit / receive control signal can be obtained by internal clock filtering. The original signal is then modulated by a radio frequency switch based on a preset carrier wave via a switching signal transmitted by a digital intermediate frequency processor to obtain the transmit / receive control signal. Furthermore, to ensure the amplitude of the transmit / receive control signal is sufficiently large, it can be amplified using a power amplifier.

[0118] Since the original signal of the transmit / receive control signal is close to a DC signal in frequency, the power supply can also be regarded as a DC signal. If the original signal and the power supply are directly combined into a first signal, it will be difficult for the antenna 105 to distinguish the original signal and the power supply when separating the first signal. Therefore, before transmitting the transmit / receive control signal, the first RRU 102 can modulate the original signal based on a preset carrier to adjust the frequency of the original signal, so that the transmit / receive control signal obtained after modulation is different from the power supply in frequency, making it easier for the antenna 105 to separate it.

[0119] The aforementioned frequency combiner 103 is specifically used to perform signal combining processing on the downlink direction, combining the first intermediate frequency signal, local oscillator signal, first radio frequency signal, transceiver control signal and power supply from the first RRU 102 to obtain a first signal; and to transmit the aforementioned first signal to the antenna 105 through the signal transmission link 104.

[0120] See Figure 4 This is a schematic diagram of the structure of the second type of first RRU and frequency combiner provided in the embodiment of the present invention.

[0121] As mentioned above Figure 2 Compared to the illustrated embodiment, the first RRU102 further includes a switch 102J, an internal clock 102K, an RF switch 102L, and a power amplifier 102D for power amplification of the transmit / receive control signals. And with... Figure 2 Compared to the illustrated embodiment, a media multiplexer 103D is used instead. Figure 2 The system includes a duplexer 103A and a filter 103B. The dielectric multiplexer 103D contains four filters 103D1, each of which is used to process the radio frequency (RF) signal, intermediate frequency (IF) signal, local oscillator (LO) signal, and transmit / receive control signal, respectively. The RF channel 102F is merged into a single bidirectional RF channel 102F, and the IF channel 102G is merged into a single bidirectional IF channel 102G.

[0122] When outputting signals, the switch 102J is connected to the power amplifier 102D; when receiving signals, the switch 102J is connected to the low-noise amplifier 102E.

[0123] The antenna 105 is specifically used to separate the first signal in the downlink direction using a multiplexer to obtain a first intermediate frequency signal, a local oscillator signal, a first radio frequency signal, a transmit / receive control signal, and a power supply; remove the carrier wave from the transmit / receive control signal using a detector; and switch between the transmit signal state and the receive signal state based on the transmit / receive control signal after removing the carrier wave.

[0124] Specifically, since the transmit / receive control signal is modulated based on a preset carrier before transmission, the antenna 105 needs to remove the preset carrier from the transmit / receive control signal after separation to recover the original signal generated by the first RRU 102. For this purpose, a detector for removing the preset carrier needs to be added to the antenna 105.

[0125] See Figure 5 This is a schematic diagram of the structure of the second type of antenna provided in an embodiment of the present invention, which is consistent with the aforementioned Figure 3 Compared to the structure shown, the first signal of the input antenna 105 also includes SW (Switch), where SW represents the transmit / receive control signal. The multiplexer 105A additionally includes a filter 105A2 for processing the transmit / receive control signal. It does not include a duplexer 105B, but includes a detector 105J, a switch 105K, and a filter 105L.

[0126] Specifically, the functions of the detector 105J and filter 105L mentioned above can be found in the previous description, and will not be repeated here.

[0127] When transmitting signals, switch 105K in the RF1 processing link is connected to attenuator 105F and power amplifier 105D, and switch 105K in the IF and LO processing links is connected to attenuator 105F and power amplifier 105D.

[0128] When receiving signals, switch 105K in the RF1 processing link is connected to attenuator 105F and low noise amplifier 105E, and switch 105K in the IF and LO processing links is connected to attenuator 105F and low noise amplifier 105E.

[0129] As can be seen from the above, if the aforementioned dual-channel MIMO indoor distributed network system performs signal processing based on the TDD standard, it cannot simultaneously transmit and receive signals. Therefore, it is necessary to control the antenna to switch between transmit and receive signal states, performing either signal transmission or signal reception only at any given time. To this end, the first RRU generates an additional transmit / receive control signal, which is combined with a first signal sent to the antenna. After receiving the first signal and separating it from the transmit / receive control signal, the antenna can switch between transmit and receive signal states, enabling the aforementioned dual-channel MIMO indoor distributed network system to support TDD-based signal processing.

[0130] If the aforementioned dual-channel MIMO indoor distributed network system performs signal processing based on the FDD (Frequency Division Duplexing) standard, then this dual-channel MIMO indoor distributed network system can simultaneously transmit and receive signals. Therefore, the first RRU does not need to send transmit / receive control signals, nor does it need to install a detector in the dual-channel MIMO indoor distributed network system. Thus, the structure of the aforementioned dual-channel MIMO indoor distributed network system can be as described above. Figure 1 The structure shown, which is the dual-channel MIMO indoor distribution network system provided in this embodiment of the invention, can support both TDD and FDD signal processing.

[0131] In another embodiment of the present invention, the above-mentioned indoor distributed network system includes a coupler, each coupler corresponding to an antenna 105. The input port of the coupler is directly or indirectly connected to the common antenna port of the first signal output by the frequency combiner 103. The coupling port of the coupler is connected to the input port of the corresponding antenna 105. The low-pass element included in the coupler is connected between the input port and the coupling port of the coupler.

[0132] The aforementioned low-pass components can be high-frequency inductors, low-pass filters, quarter-wavelength microstrip lines, etc., serving as the feed path in the coupler.

[0133] The aforementioned coupler is used to feed a first signal received through the input port into the coupling port, wherein the power supply contained in the first signal is fed into the coupling port through the aforementioned low-pass element.

[0134] In one embodiment of the present invention, the input port of the coupler is directly or indirectly connected to the common antenna port of the frequency combiner 103, so the input port of the coupler can receive the first signal output by the frequency combiner 103. As can be seen from the working principle of the coupler, the coupler can feed the high-frequency signal in the first signal input to the input port into the coupling port. Specifically, the high-frequency signal includes a first radio frequency signal, a first intermediate frequency signal, and a local oscillator signal, but the power supply can be considered a DC signal, which is not a high-frequency signal. The coupler cannot directly feed the power supply into the coupling port. Therefore, in the scheme provided by the embodiment of the present invention, a low-pass element is connected between the input port and the coupling port of the coupler to feed the power supply in the first signal from the input port into the coupling port.

[0135] Specifically, the coupler can be included in the signal transmission link 104 and connected to the antenna 105, or it can be installed in the same device as the antenna 105, in which case the antenna 105 and the coupler together form a device.

[0136] If the coupler is included in the signal transmission link 104, the housing of the antenna 105 may include an interface as an input port connected to the coupling port of the coupler. If the coupler and the antenna 105 are installed in the same device, the housing of the device may include two different interfaces as the input port and the through port of the coupler, respectively.

[0137] See Figure 6 This is a schematic diagram of a coupler provided in an embodiment of the present invention.

[0138] As shown in the figure, the above coupler includes an input port, a coupling port, a through port, a coupling line, a DC blocking capacitor, and an absorption load. The curve between the input port and the coupling port is a low-pass element. The other parts are similar in structure to couplers in the prior art, and will not be described in detail here.

[0139] In another embodiment of the present invention, the antennas included in the above-mentioned indoor distributed network system form at least one antenna group. The couplers corresponding to each antenna 105 in each antenna group are connected sequentially according to the connection order. The input port of the coupler corresponding to the antenna at the beginning of the connection order is connected to the above-mentioned common antenna port. The through port of the coupler corresponding to each first antenna is connected to the input port of the coupler corresponding to the next antenna 105 in the connection order. The through port of the coupler corresponding to the second antenna is connected to the load device.

[0140] The second antenna mentioned above is the antenna located at the end of the connection sequence in the antenna group, and the first antenna mentioned above is the other antenna in the antenna group besides the second antenna.

[0141] Specifically, the above-mentioned indoor distributed antenna system may include one or more antenna groups. Furthermore, the embodiments of the present invention do not limit the specific number of antennas included in each antenna group. If the above-mentioned indoor distributed antenna system includes multiple antenna groups, the number of antennas included in each antenna group may be the same or different.

[0142] Each antenna group may contain one or more antennas. If each antenna group contains only one antenna, then that antenna serves as both the first antenna and the second antenna. The input port of that antenna is directly connected to the common antenna port of the frequency combiner 103, and the through port is directly connected to the load device.

[0143] The input port of the coupler at the front end of each antenna group is connected to the common antenna port of the frequency combiner 103, and can directly receive the first signal. The input ports of the couplers corresponding to the other antennas 105 are all connected to the through port of the previous antenna 105 in the antenna group. After each coupler receives the first signal through its input port, in addition to feeding the first signal into the coupling port, it will also output the first signal from the through port, so that the next coupler connected to the through port can also receive the first signal, thereby enabling each coupler in the antenna group to receive the aforementioned first signal.

[0144] Furthermore, if the through port of the coupler corresponding to the second antenna is empty (i.e., not connected to a load device), the first signal will be output through the through port of the second antenna, resulting in signal reflection and affecting the signal transmission process of antenna 105. Therefore, to ensure the quality of the signal transmitted by antenna 105, a load device is connected to the through port of the second antenna in this embodiment of the invention. For example, the load device can be an antenna or other load devices, such as a 50-ohm load.

[0145] As can be seen from the above, in each antenna group provided in the embodiments of the present invention, the coupler corresponding to each antenna can receive the first signal output by the frequency combiner and feed the received first signal into the corresponding antenna, so that the antenna can transmit signals outward. This enables the dual-channel MIMO indoor distribution network system provided in the embodiments of the present invention to support a large number of antennas working together and to complete large-scale network coverage.

[0146] See Figure 7 This is a schematic diagram of a coupler and antenna provided in an embodiment of the present invention.

[0147] Specifically, Figure 7 The coupler and antenna shown are configured in the same device. The part enclosed by the solid line is the antenna, and the rest is the coupler. The square to the left of the top horizontal line represents the coupler's input port, and the square to the right represents the coupler's through port. The structure of the coupler is the same as described above. Figure 6 The embodiment shown is the same, and the antenna structure is the same as described above. Figure 3 The embodiments shown are the same. Further details regarding these embodiments will not be repeated here.

[0148] Next, in the following text Figure 8 and Figure 9 The structure of the antenna array in the indoor distributed antenna network system is illustrated in the diagram. It should be noted that... Figure 8 and Figure 9 Each antenna group contains four different antenna groups. The figure shows only one embodiment. This invention does not limit the number of antenna groups in an indoor distributed antenna network system.

[0149] See Figure 8This is a schematic diagram of the structure of a second type of dual-path MIMO indoor distribution network system provided in an embodiment of the present invention.

[0150] The structure and function of BBU101, the first RRU102, and the frequency combiner 103 in the figure have been described above and will not be repeated here.

[0151] Figure 8 Each dashed box encloses an antenna group. This indoor distributed antenna network system contains four different antenna groups. To input the first signal into these four different antenna groups, the signal transmission link in this embodiment includes a power divider to split the first signal into four paths, each input into a different antenna group. Furthermore, signals transmitted in the uplink direction from antennas in different antenna groups to the frequency combiner 103 can be combined into a single signal, and the combined signal can be transmitted to the frequency combiner 103.

[0152] Figure 8 In the indoor distributed network system shown, the coupler is located in the signal transmission link. The mushroom-shaped device in the figure represents antenna 105. The rectangle above each antenna 105 represents the coupler corresponding to that device. The square box on the left side of each coupler represents the input port of the coupler, and the square box on the right side represents the through port of the coupler. At the very end of each antenna group is an antenna that serves as a load device. The antenna here is only one form of load device, and the embodiment of the present invention does not limit the form of the load device.

[0153] See Figure 9 This is a schematic diagram of the structure of the third type of dual-path MIMO indoor distribution network system provided in the embodiments of the present invention.

[0154] The structure and function of BBU101, the first RRU102, and the frequency combiner 103 in the figure have been described above and will not be repeated here.

[0155] Figure 9 Each dashed box encloses an antenna group. This indoor distributed antenna network system contains four different antenna groups. To input the first signal into these four different antenna groups, the signal transmission link in this embodiment includes a power divider to split the first signal into four paths, each input into a different antenna group. Furthermore, signals transmitted in the uplink direction from antennas in different antenna groups to the frequency combiner 103 can be combined into a single signal, and the combined signal can be transmitted to the frequency combiner 103.

[0156] Figure 9In the indoor distributed network system shown, the coupler and antenna are installed in the same device. The mushroom-shaped device in the figure represents a device containing an antenna and a coupler. The square box on the left side of each device represents the input port of the device, which is connected to the input port of the coupler contained in the device. The square box on the right side represents the through port of the device, which is connected to the through port of the coupler contained in the device. The rectangle connected to the very end of each antenna group represents the load device.

[0157] In another embodiment of the present invention, the antenna 105 further includes a transmit / receive gain adjustment circuit. For each antenna group, the transmit / receive gain of the transmit / receive gain adjustment circuit configured on the antenna 105 located further back in the connection sequence is greater.

[0158] Specifically, the aforementioned transmit / receive gain adjustment circuit may include an attenuator and power amplifier in the downlink link, and an attenuator and low-noise amplifier in the uplink link. The location and function of the attenuator, power amplifier, and low-noise amplifier within the antenna link can be found in the preceding text. Figure 3 The embodiments shown will not be described in detail here.

[0159] The aforementioned transmit / receive gain adjustment circuit can adjust the signals transmitted and received by antenna 105, thereby improving the signal transmission and reception performance of antenna 105.

[0160] Specifically, the first signal passes through various couplers during transmission, causing interference. Theoretically, the longer the transmission link the first signal passes through, the more severe the interference. In other words, the more severe the interference is received by the antenna 105 located further back in the connection sequence of each antenna group. Interference with the first signal will affect the quality of the signal transmitted by the antenna 105. Therefore, the signal can be adjusted by the downlink transmit / receive gain adjustment circuit before the antenna 105 transmits the signal.

[0161] In addition, in the uplink direction, the antenna 105 will also be subject to interference during the transmission of signals to the frequency combiner 103. Theoretically, the longer the transmission link the signal passes through during transmission, the more severe the interference will be. That is, the signal output by the antenna 105 located further back in the connection sequence of each antenna group will be subject to more severe interference. Therefore, the uplink transmit / receive gain adjustment circuit can be used to adjust the signal before the antenna 105 transmits the signal to the frequency combiner 103.

[0162] To ensure that the quality of signals transmitted by each antenna 105 and the quality of signals sent to the inter-frequency combiner 103 are approximately consistent, different transmit / receive gains need to be configured for the transmit / receive gain adjustment links within each antenna 105 according to the degree of interference to the signals transmitted or received by each antenna 105. The greater the interference, the greater the transmit / receive gain needs to be configured. That is, the transmit / receive gain of the transmit / receive gain adjustment circuit configured for the antenna 105 located further back in the connection sequence is greater.

[0163] As can be seen from the above, by configuring different transmit and receive gains for different antennas, the quality of the signals transmitted by each antenna 105 and the quality of the signals sent to the frequency combiner 103 can be kept approximately consistent, thereby enabling each antenna in the entire indoor distribution network system to achieve approximately the same transmit and receive signal effect.

[0164] In one embodiment of the present invention, the antenna 105 includes an interface component that can adjust the transmit / receive gain of the transmit / receive gain adjustment circuit. The interface component includes at least one of the following components: jumper, DIP switch, knob, and button.

[0165] Specifically, the aforementioned transmit / receive gain adjustment circuit includes an attenuator with six control signals. By adjusting the values ​​of each control signal, the attenuation level of the signal can be controlled, thereby adjusting the transmit / receive gain of the circuit. The method of adjusting the attenuator is prior art and will not be described further in this embodiment.

[0166] In this embodiment of the invention, the antenna housing may include an interface for adjusting the transmit and receive gain of the transmit and receive gain adjustment circuit. This interface is connected to the control interface of the attenuator for adjusting the control signal, and can be connected to an external interface component. Users can adjust the transmit and receive gain of the transmit and receive gain adjustment circuit through this interface component, thereby facilitating the flexible configuration of the transmit and receive gain of each antenna.

[0167] In another embodiment of the present invention, when the above-mentioned dual-channel MIMO indoor distribution network system performs signal processing based on the TDD standard,

[0168] The aforementioned first RRU102 is specifically used to generate a first local oscillator signal for frequency conversion of the first intermediate frequency signal when the control antenna enters the signal transmission state; to send the first intermediate frequency signal, the first local oscillator signal, the first radio frequency signal, and power supply to the inter-frequency combiner 103; and to generate a second local oscillator signal for frequency conversion of the first intermediate frequency signal when the control antenna 105 enters the signal reception state; and to send the first intermediate frequency signal, the second local oscillator signal, the first radio frequency signal, and power supply to the inter-frequency combiner 103.

[0169] The power or frequency of the first local oscillator signal and the second local oscillator signal are different.

[0170] Specifically, both the first local oscillator signal and the second local oscillator signal are local oscillator signals, which can be used to convert the first intermediate frequency signal. The processing procedure of the first RRU102 for the first local oscillator signal and the second local oscillator signal is the same as the processing procedure of the first RRU102 for the local oscillator signal mentioned above, and will not be repeated here.

[0171] The antenna 105 is specifically used to enter a signal transmission state when the first signal is separated and processed by a multiplexer to obtain a first local oscillator signal, and to enter a signal reception state when the first signal is separated and processed by a multiplexer to obtain a second local oscillator signal.

[0172] Specifically, the process by which antenna 105 processes the first local oscillator signal or the second local oscillator signal can be found in the preceding description. Figure 1 The process by which the antenna 105 processes the local oscillator signal is not described in detail here.

[0173] As mentioned above Figure 1 Compared to the illustrated embodiment, the only difference is that since the power or frequency of the first local oscillator signal and the second local oscillator signal are different, the antenna 105 can determine whether the local oscillator signal generated by the first RRU 102 is the first local oscillator signal or the second local oscillator signal based on the power or frequency of the local oscillator signal obtained by the multiplexer separation processing. Thus, it can enter the signal transmission state when the first local oscillator signal is received and enter the signal reception state when the second local oscillator signal is received, thereby enabling the antenna 105 to switch between the signal transmission state and the signal reception state.

[0174] As can be seen from the above, if the signal processing in the solution provided by the embodiments of the present invention is based on the TDD standard, the first RRU can transmit the first local oscillator signal or the second local oscillator signal to the antenna by adjusting the power or frequency of the local oscillator signal, thereby controlling the antenna to switch between the signal transmission state and the signal reception state. Moreover, the first RRU does not need to send an additional transmit / receive control signal to control the antenna to switch between the signal transmission state and the signal reception state, making the structure of the first RRU, the frequency combiner and the antenna in the indoor distributed network system provided by the embodiments of the present invention relatively simple.

[0175] In another embodiment of the present invention, the antenna 105 is capable of performing multiplexing of the first signal in the downlink direction to obtain first radio frequency signals of different frequency bands, and is capable of receiving third radio frequency signals of different frequency bands and fourth radio frequency signals of different frequency bands in the uplink direction.

[0176] The aforementioned frequency combiner 103 can perform signal combining processing on first radio frequency signals of different frequency bands in the downlink direction, and can separate the second signal from antenna 105 into a fourth radio frequency signal of different frequency bands in the uplink direction.

[0177] Specifically, regardless of the frequency bands of the first and fourth radio frequency signals, the processing procedure of the antenna 105 and the frequency combiner 103 for the first and fourth radio frequency signals is the same as described above. Figure 1 The embodiments shown are all similar, and will not be described again in the embodiments of the present invention.

[0178] As can be seen from the above, the indoor distributed network system provided in this embodiment of the invention can transmit and receive signals of various frequencies, and the signals processed by the indoor distributed network system can switch between different frequency bands, supporting the processing of signals of different frequency bands.

[0179] In one embodiment of the present invention, the above-mentioned indoor distributed network system further includes a second RRU.

[0180] See Figure 10 This is a schematic diagram of the fourth type of dual-path MIMO indoor distribution network system provided in this embodiment of the invention, which is consistent with the aforementioned... Figure 1 Compared to the illustrated embodiment, the above-described indoor distributed network system further includes a second RRU106, and with Figure 1 In addition to the frequency combiner 103, there is also a filter for processing the fifth and sixth radio frequency signals.

[0181] The aforementioned second RRU106 is used to convert a downlink baseband modulation signal from BBU101 into a fifth radio frequency signal in the downlink direction, and send the fifth radio frequency signal to the frequency combiner 103.

[0182] The frequency of the fifth radio frequency signal is different from that of the first radio frequency signal.

[0183] Specifically, unlike the first RRU102, the second RRU106 does not output power to the outside and only outputs one fifth radio frequency signal. The second RRU106 can process signals based on the FDD standard.

[0184] The second RRU106 mentioned above can be the same as the RRU in the prior art, transmitting a high-power fifth radio frequency signal. For example, the power of the fifth radio frequency signal can be 100W and the frequency of the fifth radio frequency signal can be 1.8GHz. Unlike the fifth radio frequency signal, the frequencies of the first radio frequency signal and the second radio frequency signal can be 2.6GHz.

[0185] The second RRU106 mentioned above can also transmit a low-power fifth radio frequency signal, similar to the first RRU mentioned above.

[0186] The aforementioned frequency combiner 103 is specifically used to perform signal combining processing on the downlink direction, combining the first intermediate frequency signal, local oscillator signal, first radio frequency signal, power supply from the first RRU 102 and the fifth radio frequency signal from the second RRU 106 to obtain a first signal.

[0187] As mentioned above Figure 1 Compared to the embodiments shown, the above-mentioned frequency combiner 103 not only performs combination processing on the first intermediate frequency signal, the local oscillator signal, the first radio frequency signal, and the power supply, but also combines the fifth radio frequency signal into the first signal.

[0188] The antenna 105 is specifically used to separate the first signal in the downlink direction using a multiplexer to obtain a first intermediate frequency signal, a local oscillator signal, a first radio frequency signal, a power supply signal, and a fifth radio frequency signal.

[0189] The aforementioned antenna 105 is also used to transmit a fifth radio frequency signal; and in the uplink direction, to receive a sixth radio frequency signal transmitted by the terminal.

[0190] Specifically, if the fifth radio frequency signal output by the second RRU106 is a high-power signal, the antenna 105 may not amplify the power of the fifth radio frequency signal, but may directly filter the fifth radio frequency signal through a filter and transmit it outward through one of the antenna arrays in the two-polarized antenna array.

[0191] If the fifth radio frequency signal output by the second RRU106 is not a high-power signal, the antenna 105 can first amplify the power of the fifth radio frequency signal through a power amplifier, and then filter the amplified fifth radio frequency signal through a filter before transmitting it outward through one of the antenna arrays in the two-polarized antenna array.

[0192] Specifically, the method of power amplification of the fifth radio frequency signal is the same as the method of power amplification of the first radio frequency signal by the aforementioned antenna 105, and will not be repeated here.

[0193] The antenna 105 is specifically used to perform signal combining processing on the second intermediate frequency signal, the fourth radio frequency signal, and the sixth radio frequency signal through a multiplexer to obtain the second signal.

[0194] Specifically, after receiving the sixth radio frequency signal, antenna 105 can directly perform signal combining on the sixth radio frequency signal. Alternatively, the sixth radio frequency signal can be amplified by a low-noise amplifier before being combined.

[0195] The method for amplifying the sixth radio frequency signal is the same as the method for amplifying the fourth radio frequency signal by the aforementioned antenna 105, and will not be repeated here.

[0196] Therefore, the antenna 105 needs to transmit not only the first radio frequency (RF) signal, but also the second and fifth RF signals, and the first, second, and fifth RF signals operate in different frequency bands. Furthermore, the antenna 105 needs to receive not only the third and fourth RF signals, but also the sixth RF signal, and the third, fourth, and sixth RF signals operate in different frequency bands. Therefore, the antenna 105 needs to support signal transmission and reception in different frequency bands. The antenna 105 supports a wide frequency band; if the fifth RF signal has a frequency of 1.8 GHz (different from the first RF signal), and the first and second RF signals have frequencies of 2.6 GHz, then the operating frequency band of the antenna 105 can be 1.7-2.7 GHz.

[0197] The aforementioned frequency combiner is specifically used to separate the second signal from antenna 105 into a fourth radio frequency signal, a second intermediate frequency signal, and a sixth radio frequency signal in the uplink direction; to send the fourth radio frequency signal and the second intermediate frequency signal to the first RRU 102, and to send the sixth radio frequency signal to the second RRU 106.

[0198] Specifically, the processing method of the first RRU102 for the fourth radio frequency signal and the second intermediate frequency signal can be found in the aforementioned... Figure 1 The embodiments shown are not described in detail in this embodiment of the invention.

[0199] In addition, the second RRU can directly convert the sixth radio frequency signal into an uplink baseband modulation signal and send the uplink baseband modulation signal to BBU101.

[0200] The second RRU106 may also include a low-noise amplifier, which can amplify the sixth RF signal and then convert it into an uplink baseband modulation signal for transmission to BBU101. Specifically, the method by which the second RRU106 amplifies the sixth RF signal is the same as the method by which the first RRU102 amplifies the third and fourth RF signals, and will not be repeated here.

[0201] The second RRU106 processes signals based on the FDD standard, and the first RRU102 can process signals based on either the FDD or TDD standard. If the second RRU106 processes signals based on the FDD standard and the first RRU102 processes signals based on the TDD standard, then the indoor distributed network system provided in this embodiment of the invention can simultaneously support signal processing based on both the TDD and FDD standards.

[0202] See Figure 11 This is a schematic diagram of the structure of the third type of antenna provided in an embodiment of the present invention, which is consistent with the aforementioned Figure 3Compared to the illustrated embodiment, RF2 represents the fifth radio frequency signal. The multiplexer within this antenna additionally includes a filter for processing the fifth and sixth radio frequency signals, and also contains an additional filter connected to one of the antenna elements in the dual-polarized antenna array. Specifically, the function of the aforementioned filter can be found in the preceding description and will not be repeated here.

[0203] Corresponding to the aforementioned dual-channel MIMO indoor distribution network system, this embodiment of the invention also provides a dual-channel signal transceiver method.

[0204] See Figure 12 This is a flowchart illustrating a dual-channel signal transceiver method provided in an embodiment of the present invention, applied to an indoor distributed network system. The indoor distributed network system includes a BBU, a first RRU, a frequency combiner, a signal transmission link, and an antenna. The antenna is an active frequency conversion dual-polarized antenna, which includes a power amplifier, a low-noise amplifier, a multiplexer, and an active mixer. Specifically, the specific structure of the indoor distributed network system can be found in the structure of the aforementioned dual-channel MIMO indoor distributed network system, and the specific structures of the various devices included in the indoor distributed network system can also be found in the aforementioned embodiments, and will not be repeated here.

[0205] The above method includes the following steps S1201-S1211.

[0206] S1201: Send downlink baseband modulation signal to the first RRU through the above BBU.

[0207] Each set of downlink baseband modulation signals contains two signals.

[0208] S1202: In the downlink direction, the first RRU converts two signals contained in a set of downlink baseband modulation signals into a first radio frequency signal and a first intermediate frequency signal, respectively, and generates a local oscillator signal for frequency conversion of the first intermediate frequency signal.

[0209] S1203: Output a power supply through the first RRU to send the aforementioned first radio frequency signal, first intermediate frequency signal, local oscillator signal and power supply to the frequency combiner.

[0210] S1204: In the downlink direction, the first intermediate frequency signal, local oscillator signal, first radio frequency signal and power supply from the first RRU are combined by a frequency combiner to obtain a first signal.

[0211] S1205: The first signal mentioned above is sent from the frequency combiner to the antenna via the signal transmission link.

[0212] S1206: In the downlink direction, the first signal is separated by a multiplexer through the antenna to obtain a first intermediate frequency signal, a local oscillator signal, a first radio frequency signal, and a power supply. The power supply powers the active mixer, which converts the first intermediate frequency signal into a second radio frequency signal based on the local oscillator signal. The power supply powers the power amplifier, which amplifies the first radio frequency signal and the second radio frequency signal.

[0213] The first radio frequency signal and the second radio frequency signal have the same frequency.

[0214] S1207: Transmits the first radio frequency signal and the second radio frequency signal after power amplification through the antenna respectively.

[0215] S1208: Receives the third and fourth radio frequency signals transmitted by the terminal in the uplink direction via the antenna, powers a low-noise amplifier, amplifies the third and fourth radio frequency signals via the low-noise amplifier, powers an active mixer, converts the amplified third radio frequency signal into a second intermediate frequency signal based on the local oscillator signal via the active mixer, and performs signal combining processing on the second intermediate frequency signal and the fourth radio frequency signal via a multiplexer to obtain the second signal.

[0216] S1209: Send a second signal from the antenna to the frequency combiner via the signal transmission link.

[0217] S1210: In the uplink direction, the second signal from the antenna is separated into a fourth radio frequency signal and a second intermediate frequency signal by a frequency combiner, and the fourth radio frequency signal and the second intermediate frequency signal are sent to the first RRU.

[0218] S1211: The first RRU converts the fourth radio frequency signal and the second intermediate frequency signal into two uplink baseband modulation signals in the uplink direction, and sends the two uplink baseband modulation signals to the BBU.

[0219] Specifically, the dual-channel signal transceiver method implemented in the above-mentioned indoor distributed network system is similar to that described above. Figure 1 The dual-channel MIMO indoor distribution network system shown performs the same steps when receiving and transmitting signals, and will not be described again in this embodiment of the invention.

[0220] As can be seen from the above, the embodiments of the present invention provide a dual-channel MIMO indoor distributed network system. The antennas included in this system can transmit at least two radio frequency signals with the same frequency, meaning the system supports dual-channel MIMO functionality. Furthermore, in this system, the signal transmitted by the first RRU to the antenna via a frequency combiner includes a power supply, meaning the first RRU can power the antenna through this supply. This indicates the antenna in the system is an active antenna, enabling it to use an active mixer (which operates only when powered) to convert the first intermediate frequency signal to a second radio frequency signal based on the local oscillator signal. The antenna can also use a power amplifier (which operates only when powered) to amplify the power of the first and second radio frequency signals, allowing it to transmit high-power signals. Therefore, the antenna in the indoor distributed network system provided by the embodiments of the present invention can amplify the transmitted signal itself, ensuring a high-power signal. The first RRU does not need to transmit a high-power signal to the antenna, thus eliminating the need for expensive high-power output devices in the first RRU, thereby reducing the cost of the indoor distributed network system. Furthermore, after receiving the third and fourth radio frequency signals, the antenna can use a low-noise amplifier, which can only be used when powered on, to amplify the third and fourth radio frequency signals. This allows the dual-channel MIMO indoor distribution network system provided in this embodiment of the invention to also improve the power of the received third and fourth radio frequency signals without requiring the terminal to transmit a high-power signal. The dual-channel MIMO indoor distribution network system provided in this embodiment of the invention can also ensure the power of the uplink signal reported by the terminal.

Claims

1. A dual-channel MIMO indoor distribution network system, characterized in that, The indoor distributed network system includes a baseband processing unit (BBU), a first radio frequency pull unit (RRU), a frequency combiner, a signal transmission link, and an antenna. The antenna is an active frequency conversion dual-polarized antenna and includes a power amplifier, a low-noise amplifier, a multiplexer, and an active mixer. The BBU is used to send downlink baseband modulation signals to the first RRU, wherein each set of downlink baseband modulation signals contains two signals. The first RRU is used to convert two signals contained in a set of downlink baseband modulation signals into a first radio frequency signal and a first intermediate frequency signal respectively in the downlink direction, and generate a local oscillator signal for frequency conversion of the first intermediate frequency signal; output a power supply to send the first radio frequency signal, the first intermediate frequency signal, the local oscillator signal and the power supply to the frequency combiner. The frequency combiner is used to combine the first intermediate frequency signal, local oscillator signal, first radio frequency signal and power supply from the first RRU in the downlink direction to obtain a first signal; and transmit the first signal to the antenna through the signal transmission link. The antenna is used to separate the first signal in the downlink direction using a multiplexer to obtain a first intermediate frequency signal, a local oscillator signal, a first radio frequency signal, and a power supply; to power an active mixer with the power supply, and to convert the first intermediate frequency signal into a second radio frequency signal based on the local oscillator signal using the active mixer; to power a power amplifier with the power supply, and to amplify the first radio frequency signal and the second radio frequency signal using the power amplifier; and to transmit the amplified first radio frequency signal and the second radio frequency signal respectively, wherein the first radio frequency signal and the second radio frequency signal have the same frequency. The antenna is also used to receive a third radio frequency signal and a fourth radio frequency signal transmitted by the terminal in the uplink direction; to power a low-noise amplifier with a power supply, and to amplify the third radio frequency signal and the fourth radio frequency signal through the low-noise amplifier; to power an active mixer with a power supply, and to convert the amplified third radio frequency signal into a second intermediate frequency signal based on the local oscillator signal through the active mixer; to perform signal combining processing on the second intermediate frequency signal and the fourth radio frequency signal through a multiplexer to obtain a second signal; and to send the second signal to the frequency combiner through a signal transmission link. The frequency combiner is also used to separate the second signal from the antenna into a fourth radio frequency signal and a second intermediate frequency signal in the uplink direction, and send the fourth radio frequency signal and the second intermediate frequency signal to the first RRU. The first RRU is also used to convert the fourth radio frequency signal and the second intermediate frequency signal into two uplink baseband modulation signals in the uplink direction, and send the two uplink baseband modulation signals to the BBU.

2. The dual-path MIMO room division network system of claim 1, wherein, In the case where the dual-channel MIMO indoor distribution network system performs signal processing based on the time-division duplex (TDD) standard, the antenna also includes a detector; The first RRU is specifically used to output a transmit / receive control signal in the downlink direction, and to modulate the transmit / receive control signal based on a preset carrier, and to send a first radio frequency signal, a first intermediate frequency signal, a local oscillator signal, the signal-modulated transmit / receive control signal and power supply to the multi-frequency combiner. The transmit / receive control signal is used to control the antenna to switch between transmit signal state and receive signal state. The frequency combiner is specifically used to perform signal combining processing on the downlink direction, combining the first intermediate frequency signal, local oscillator signal, first radio frequency signal, transceiver control signal and power supply from the first RRU to obtain a first signal; and to transmit the first signal to the antenna through the signal transmission link; The antenna is specifically used to separate the first signal in the downlink direction using a multiplexer to obtain a first intermediate frequency signal, a local oscillator signal, a first radio frequency signal, a transmit / receive control signal, and a power supply. The carrier wave in the transmit / receive control signal is removed by a detector; based on the transmit / receive control signal after removing the carrier wave, the system switches between transmit signal state and receive signal state.

3. The dual-path MIMO room division network system of claim 1, wherein, The indoor distributed network system includes couplers, each coupler corresponding to an antenna. The input port of the coupler is directly or indirectly connected to the common antenna port of the first signal output by the frequency combiner. The coupling port of the coupler is connected to the input port of the corresponding antenna. The low-pass element included in the coupler is connected between the input port and the coupling port of the coupler. The coupler is used to feed a first signal received through the input port into the coupling port, wherein the power contained in the first signal is fed into the coupling port through the low-pass element.

4. The dual-channel MIMO indoor distribution network system according to claim 3, characterized in that, The indoor distributed antenna system includes at least one antenna group. The couplers corresponding to each antenna in each antenna group are connected sequentially according to the connection order. The input port of the coupler corresponding to the antenna at the beginning of the connection order is connected to the common antenna port. The through port of the coupler corresponding to each first antenna is connected to the input port of the coupler corresponding to the next antenna in the connection order. The through port of the coupler corresponding to the second antenna is connected to the load device. The second antenna is the antenna at the end of the connection order in the antenna group, and the first antenna is any antenna in the antenna group other than the second antenna.

5. The dual-path MIMO room division network system of claim 4, wherein, The antenna also includes a transmit / receive gain adjustment circuit. For each antenna group, the transmit / receive gain of the antenna configured with the transmit / receive gain adjustment circuit is greater the further back in the connection sequence.

6. The dual-path MIMO room division network system of claim 5, wherein, The antenna includes an interface component capable of adjusting the transmit / receive gain of the transmit / receive gain adjustment circuit. The interface component includes at least one of the following components: jumper, DIP switch, knob, and button.

7. The dual-channel MIMO indoor distribution network system according to claim 1, characterized in that, In the case where the dual-channel MIMO indoor distribution network system performs signal processing based on the TDD standard... The first RRU is specifically configured to, when the control antenna enters the signal transmission state, generate a first local oscillator signal for frequency conversion of the first intermediate frequency signal; send the first intermediate frequency signal, the first local oscillator signal, the first radio frequency signal, and power to the frequency combiner; when the control antenna enters the signal reception state, generate a second local oscillator signal for frequency conversion of the first intermediate frequency signal; and send the first intermediate frequency signal, the second local oscillator signal, the first radio frequency signal, and power to the frequency combiner, wherein the power or frequency of the first local oscillator signal and the second local oscillator signal are different. Specifically, the antenna is used to enter a signal transmission state when the first signal is separated and processed by a multiplexer to obtain a first local oscillator signal, and to enter a signal reception state when the first signal is separated and processed by a multiplexer to obtain a second local oscillator signal.

8. The dual-channel MIMO indoor distribution network system according to any one of claims 1-7, characterized in that, The antenna can separate and process the first signal in the downlink direction through a multiplexer to obtain first radio frequency signals of different frequency bands, and can receive third radio frequency signals of different frequency bands and fourth radio frequency signals of different frequency bands in the uplink direction. The frequency combiner can perform signal combining processing on first radio frequency signals of different frequency bands in the downlink direction, and can separate the second signal from the antenna into a fourth radio frequency signal of different frequency bands in the uplink direction.

9. The dual-channel MIMO indoor distribution network system according to claim 8, characterized in that, The indoor distribution network system also includes a second RRU; The second RRU is used to convert a downlink baseband modulation signal from the BBU into a fifth radio frequency signal in the downlink direction, and send the fifth radio frequency signal to the frequency combiner, wherein the frequency of the fifth radio frequency signal is different from the frequency of the first radio frequency signal; The frequency combiner is specifically used to perform signal combining processing on the downlink direction, combining the first intermediate frequency signal, local oscillator signal, first radio frequency signal, power supply from the first RRU and the fifth radio frequency signal from the second RRU to obtain a first signal; The antenna is specifically used to separate the first signal in the downlink direction using a multiplexer to obtain a first intermediate frequency signal, a local oscillator signal, a first radio frequency signal, a power supply signal, and a fifth radio frequency signal. The antenna is also used to transmit a fifth radio frequency signal; and in the uplink direction, to receive a sixth radio frequency signal transmitted by the terminal; The antenna is specifically used to perform signal combining processing on the second intermediate frequency signal, the fourth radio frequency signal, and the sixth radio frequency signal through a multiplexer to obtain the second signal. The frequency combiner is specifically used to separate the second signal from the antenna into a fourth radio frequency signal, a second intermediate frequency signal, and a sixth radio frequency signal in the uplink direction; send the fourth radio frequency signal and the second intermediate frequency signal to the first RRU, and send the sixth radio frequency signal to the second RRU.

10. The dual-path MIMO room division network system of any of claims 1-7, wherein, The antenna also includes: a dual-polarized antenna array; Specifically, the antenna is used to transmit a first radio frequency signal and a second radio frequency signal with amplified power through two antenna arrays in the downlink direction; and to receive a third radio frequency signal and a fourth radio frequency signal transmitted by the terminal through two antenna arrays in the uplink direction.

11. A two-way signal transceiving method, characterized by, Applied to an indoor distributed network system, the indoor distributed network system includes a baseband processing unit (BBU), a first radio frequency pull unit (RRU), a frequency combiner, a signal transmission link, and an antenna. The antenna is an active frequency conversion dual-polarized antenna, and the antenna includes: a power amplifier, a low-noise amplifier, a multiplexer, and an active mixer. The BBU sends downlink baseband modulation signals to the first RRU, wherein each set of downlink baseband modulation signals contains two signals; In the downlink direction, the first RRU converts two signals contained in a set of downlink baseband modulation signals into a first radio frequency signal and a first intermediate frequency signal, respectively, and generates a local oscillator signal for frequency conversion of the first intermediate frequency signal; The first RRU outputs a power supply to send the first radio frequency signal, the first intermediate frequency signal, the local oscillator signal and the power supply to the frequency combiner. In the downlink direction, the first intermediate frequency signal, local oscillator signal, first radio frequency signal and power supply from the first RRU are combined by a frequency combiner to obtain a first signal. The first signal is transmitted from the frequency combiner to the antenna via a signal transmission link; In the downlink direction, the first signal is separated by a multiplexer through an antenna to obtain a first intermediate frequency signal, a local oscillator signal, a first radio frequency signal, and a power supply. The power supply powers an active mixer, which converts the first intermediate frequency signal into a second radio frequency signal based on the local oscillator signal. The power supply powers a power amplifier, which amplifies the first and second radio frequency signals. The first and second radio frequency signals have the same frequency. The first and second radio frequency signals, after being amplified by power, are transmitted through the antenna, respectively. The antenna receives the third and fourth radio frequency signals transmitted by the terminal in the uplink direction. The power supply powers the low noise amplifier, which amplifies the third and fourth radio frequency signals. The power supply powers the active mixer, which converts the amplified third radio frequency signal into a second intermediate frequency signal based on the local oscillator signal. The multiplexer performs signal combining on the second intermediate frequency signal and the fourth radio frequency signal to obtain the second signal. A second signal is transmitted from the antenna to the frequency combiner via a signal transmission link; In the uplink direction, the second signal from the antenna is separated into a fourth radio frequency signal and a second intermediate frequency signal by a frequency combiner, and the fourth radio frequency signal and the second intermediate frequency signal are sent to the first RRU. The first RRU converts the fourth radio frequency signal and the second intermediate frequency signal into two uplink baseband modulation signals in the uplink direction, and sends the two uplink baseband modulation signals to the BBU.

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