Active antenna unit and communication device

Abstract

The invention provides an active antenna unit which can be applied to communication equipment with a transmitting-receiving common antenna. The active antenna unit comprises N radio frequency antenna links and L self-interference cancellers, N is an integer greater than 1, and L is an integer less than or equal to N, for example, L is equal to N. Each radio frequency antenna link comprises a transmitting channel, a receiving channel, a feed network and an antenna subarray. The N radio frequency antenna links meet at least one of the following conditions: the routing of the feed networks of at least two radio frequency antenna links is different; or, the N antenna sub-arrays are provided with isolation assemblies which are used for isolating signals among the N antenna sub-arrays. In addition, a self-interference canceller is connected between the transmitting channel and the receiving channel of at least one link and used for cancelling signals from the transmitting channel in the receiving channel of the link where the self-interference canceller is located. Therefore, the self-interference cancellers do not need to be connected between the transmitting channels and the receiving channels of different links in the N links, the number of the self-interference cancellers can be reduced, and the circuit complexity is reduced.

Description

Technical Field

[0001] The present application relates to the field of wireless communications, and in particular to an active antenna unit and a communication device. Background Art

[0002] The working modes in the communication system include time division duplexing (TDD), frequency division duplexing (FDD), full duplex, sub-band duplex, partial full duplex and other working modes. In some working modes, such as full duplex, sub-band duplex, partial full duplex, etc., the base station may use the same group or multiple groups of antenna units to transmit and receive signals at the same time, that is, there is a situation where the transmitting and receiving antennas are shared. Since the device that shares the antenna for transmission and reception will receive the uplink signal while transmitting the downlink signal, it will receive the downlink signal transmitted by the device itself, and the received downlink signal will be coupled to the receiving link. Since the transmission power of the downlink signal is large, it will cause the receiving link to be blocked, resulting in reduced receiving performance.

[0003] In order to prevent the receiving link from being blocked, a self-interference canceller is usually used to reduce the interference of the downlink signal received by the receiving link. There are multiple links inside the self-interference canceller, each of which includes devices such as an adjustable phase shifter and an adjustable attenuator, as well as a delay device, which increases the wiring complexity and control complexity.

[0004] At present, the N (N is a positive integer) transmit-N receive architecture is usually used in base stations with a shared antenna for transmission and reception, that is, the base station uses N groups of antenna units to simultaneously transmit downlink signals and receive uplink signals. Common designs include one transmit and one receive, two transmit and two receive, four transmit and four receive, etc. Taking four transmit and four receive as an example, the base station can use four groups of antenna units to receive signals while using four groups of antenna units to transmit signals. When each group of antenna units receives uplink signals, it will not only receive the downlink signals transmitted by this group of antenna units, but also receive the downlink signals transmitted by the other three groups of antenna units. In order to prevent the receiving link from being blocked, a self-interference canceller is required between each transmitting link and each receiving link to reduce interference. Therefore, 4×4 self-interference cancellers, that is, N×N self-interference cancellers, are required.

[0005] As the number of antenna units shared by both transmitting and receiving increases, the value of N also tends to increase, the number of self-interference cancellers increases dramatically, and the complexity also increases dramatically. Summary of the invention

[0006] The present application provides an active antenna unit (AAU) and a communication device, in order to reduce the circuit complexity and control complexity in the AAU.

[0007] In the first aspect, an AAU is provided, which can be applied to a communication device, such as a network device or a terminal device. In the following text, in order to facilitate the distinction between the signals of the transmitting channel and the receiving channel, the direction of the signal is described by taking the network device as an example. For example, the signal transmitted by the transmitting channel is a downlink signal, and the signal received by the receiving channel is an uplink signal. It can be understood that in different communication devices, the direction of the signal will also change accordingly. For example, for a terminal device, the signal transmitted by the transmitting channel is an uplink signal, and the signal received by the receiving channel is a downlink signal. The following description should not limit the direction of the signal and the communication device to which the AAU is applied.

[0008] Exemplarily, the AAU includes: N RF antenna links and L self-interference cancellers, N is an integer greater than 1, and L is a positive integer less than or equal to N; each of the N RF antenna links includes: a transmitting channel, a receiving channel, a feeding network connected to the transmitting channel and the receiving channel, and an antenna subarray connected to the feeding network, the feeding network is used to feed the antenna subarray, and the antenna subarray is used to transmit and receive signals; a self-interference canceller is connected between the transmitting channel and the receiving channel of at least one RF antenna link among the N RF antenna links, and the self-interference canceller is used to eliminate the signal from the transmitting channel of the same RF antenna link in the receiving channel of the RF antenna link; wherein the N RF antenna links satisfy at least one of the following items: the routing of the feeding network in at least two of the N RF antenna links is different, or, the N antenna subarrays in the N RF antenna links are provided with an isolation component, and the isolation component is used to isolate the signals between the N antenna subarrays.

[0009] Each antenna subarray may include multiple antenna elements (or simply elements). Each antenna subarray is used to transmit and receive signals, which means that multiple antenna elements in each antenna subarray are used to transmit and receive signals. In this way, each antenna subarray can transmit and receive on the same time-frequency resources. In other words, each antenna subarray is used for both transmission and reception, or in other words, the antenna elements in each antenna subarray are used for both transmission and reception.

[0010] Taking network equipment as an example, for the downlink signal transmitted by the antenna subarray, other antenna subarrays nearby can be regarded as receivers. For the convenience of distinction and explanation, the antenna subarray that transmits the downlink signal is recorded as the transmitter antenna subarray, and the antenna subarray that receives the downlink signal is recorded as the receiver antenna subarray. It can be understood that sending and receiving are relative, and each antenna subarray can be a transmitter antenna subarray or a receiver antenna subarray. Each receiver antenna subarray may receive downlink signals from multiple transmitter antenna subarrays at the same time, and may also send downlink signals while receiving.

[0011] In this solution, the routing of the feed network of different RF antenna links is different, which may specifically refer to the different layouts of the RF lines in the printed circuit boards (PCB) in different RF antenna links. Among them, the RF line can feed the signal to be transmitted to the antenna element according to a certain amplitude and phase, or send the received signal to the processing unit of the communication device (such as a base station) according to a certain amplitude and phase. The different layouts of the RF lines may include: different lengths of the RF lines, and / or different widths of the RF lines. By making different designs for the length and / or width of the RF lines, the phases and / or amplitudes of the downlink signals sent by different RF antenna links can be different.

[0012] Therefore, when the routing of the feeding networks of at least two RF antenna links (for example, the RF antenna link where the transmitter antenna subarray is located and the RF antenna link where the receiver antenna subarray is located) is different, on the one hand, through the design of the feeding network of the transmitter antenna subarray, when the transmitter antenna subarray transmits a downlink signal, the signals received by different antenna elements in the receiver antenna subarray at the near field of the transmitter antenna subarray are in opposite phases, vector-cancelled, and the energy is reduced. Therefore, the energy of the downlink signal received by the receiver antenna subarray is reduced, and the interference is reduced. On the other hand, through the design of the feeding network of the receiver antenna subarray, after each antenna element in the receiver antenna subarray receives the downlink signal, vector-cancelled in the circuit domain can be further performed, thereby further reducing the energy of the downlink signal and the interference.

[0013] Providing isolation components for antenna subarrays can also isolate mutual interference between different antenna subarrays.

[0014] On the other hand, in order to reduce the interference of the downlink signal in this link to the receiving channel, a self-interference canceller can be connected between the receiving channel and the transmitting channel to reduce the interference of the downlink signal from this link. In this application, a self-interference canceller can be connected between the receiving channel and the transmitting channel in at least one of the N RF antenna links. In this way, by introducing one or more self-interference cancellers in the N RF antenna links, the interference of the downlink signal to the receiving channel can be further reduced.

[0015] Based on the design of the feed network and the design of setting isolation components for the antenna subarrays, the mutual interference between different antenna subarrays can be reduced, that is, the mutual interference between different RF antenna links can be reduced, so that the interference received by the receiving channel in each RF antenna link mainly comes from the downlink signal of the transmitting channel of this link. Therefore, a self-interference canceller can be connected between the transmitting channel and the receiving channel in the RF antenna link to cancel the downlink signal from the transmitting channel in this link, further reducing the interference of the receiving channel. In other words, in the solution provided by the present application, there is no need to connect a self-interference canceller between the transmitting channel and the receiving channel of any two different RF antenna links in the N RF antenna links, which greatly reduces the number of self-interference cancellers, reduces the circuit complexity, and reduces the control complexity accordingly.

[0016] Optionally, N is equal to L. In other words, a self-interference canceller is connected between a receiving channel and a transmitting channel in each of the N radio frequency antenna links.

[0017] That is to say, the N radio frequency antenna links can correspond to N self-interference cancellers one by one, and each self-interference canceller is connected to a corresponding radio frequency antenna link. Compared with the current use of N×N self-interference cancellers in N radio frequency antenna links, the number of self-interference cancellers is greatly reduced, and the circuit complexity is reduced.

[0018] Therefore, the solution provided in the present application can reduce the blockage of the receiving channel by the interfering downlink signal within each RF antenna link and between different RF antenna links, which is conducive to obtaining better receiving performance.

[0019] It is understandable that the design of the feed network and the provision of isolation components for the antenna subarrays can be implemented separately or in combination. The combination of the two methods can reduce the mutual interference between different antenna subarrays to a greater extent, reduce the blocking of the receiving channel by the downlink signal, and thus reduce the deterioration of the receiving performance, thereby obtaining better receiving performance.

[0020] In combination with the first aspect, in some possible implementations of the first aspect, the feeding network in each of the multiple RF antenna links includes one or more phase shifters, and each phase shifter is connected to one or more antenna elements.

[0021] Each phase shifter can be connected to one or more antenna elements, and can be used to adjust the beam direction of the downlink signal transmitted by the one or more connected antenna elements, and can also be used to adjust the phase of the downlink signal transmitted by the one or more connected antenna elements. On the one hand, since the phase shifter can be used to adjust the beam direction of the signal, more antenna elements can be used in the antenna subarray to transmit and receive signals. The increase in the number of antenna elements in the antenna array can make the feeding network more free, that is, the feeding network can have greater freedom to optimize its amplitude and / or phase, thereby providing strong support for optimizing higher isolation.

[0022] On the other hand, the phase shifter can be used to adjust the phase, which causes a phase difference between the downlink signals emitted by the antenna elements connected to different phase shifters in the same antenna subarray. Therefore, by controlling the phase difference, the downlink signals emitted by different antenna elements can cancel each other out and reduce mutual interference.

[0023] In combination with the first aspect, in some possible implementations of the first aspect, the isolation component includes: M decoupling units located above N antenna subarrays, where M is an integer greater than or equal to N; wherein the decoupling unit located above the first antenna subarray is used to reflect part of the received signal to offset the signal from the other antenna subarrays in the first receiving channel through the reflected signal, the first antenna subarray is any one of the N antenna subarrays, the first receiving channel is a receiving channel connected to the first antenna subarray, and the other antenna subarrays are one or more antenna subarrays among the N antenna subarrays except the first antenna subarray.

[0024] Wherein, M may be an integer multiple of N or may not be an integer multiple of N. M decoupling units may be evenly distributed and cover the top of N antenna subarrays to form an antenna decoupling surface (ADS). ADS cancels the coupling signal between adjacent antenna subarrays by creating a new reflection signal (i.e., generated by reflecting part of the received signal). Therefore, by setting M decoupling units above N antenna subarrays, the mutual coupling between the antenna subarrays can be suppressed, thereby improving the isolation between the N antenna subarrays.

[0025] In combination with the first aspect, in some possible implementations of the first aspect, the isolation component includes: at least one isolation unit located between two adjacent antenna subarrays among N antenna subarrays, and the at least one isolation unit located between adjacent antenna subarrays is used to isolate interference signals between at least some of the N antenna subarrays.

[0026] The isolation unit may be disposed between adjacent antenna subarrays to reduce interference between antenna subarrays and improve isolation between antenna subarrays by absorbing energy of downlink signals transmitted by the antenna subarrays, changing phases or amplitudes, and the like.

[0027] Each of the N antenna subarrays includes multiple antenna elements, and the isolation component further includes: at least one isolation unit located between adjacent antenna elements in each antenna subarray, and the at least one isolation unit located between the adjacent antenna elements is used to isolate interference signals between at least some of the multiple antenna elements.

[0028] The isolation unit may be further disposed between adjacent antenna elements to reduce interference between the antenna elements and improve isolation between the antenna elements.

[0029] Optionally, the at least one isolation unit is made of one or more of absorbing materials, scattering materials, and metamaterials.

[0030] Among them, absorbing materials can absorb or significantly reduce the electromagnetic wave energy received on their surface, so they can be used to prepare isolation units. Scattering materials and metamaterials can both regulate the amplitude and phase of electromagnetic waves, change their scattering and reflection paths, and thus achieve the effect of canceling downlink signals, so they can be used to prepare isolation units.

[0031] In the present application, each isolation unit can be made of one of absorbing materials, scattering materials, and metamaterials. In the case where the isolation assembly includes multiple isolation units, different isolation units can be made of the same material, such as one of absorbing materials, scattering materials, and metamaterials; different isolation units can also be made of different materials, such as multiple of absorbing materials, scattering materials, and metamaterials.

[0032] In combination with the first aspect, in some possible implementations of the first aspect, the receiving channel in each RF antenna link includes a low noise amplifier (LNA), an analog-to-digital converter (ADC), and a narrowband filter connected between the ADC and the LNA, wherein the narrowband filter is used to filter frequency signals other than a preset frequency.

[0033] That is to say, the narrowband filter can allow a signal of a preset frequency to pass through, while filtering signals of other frequencies, so that the interference of the passing signal is small. In this way, the ADC is less affected by other signals, the ADC is not saturated, the receiving link is not blocked as a whole, and the receiving performance is less affected.

[0034] Optionally, the preset frequency may be an uplink frequency.

[0035] That is, except for the uplink signal, other signals cannot pass through the narrowband filter. Connecting a narrowband filter in the receiving link is particularly suitable for working modes where the uplink and downlink use different frequency bands, such as the sub-band duplex working mode.

[0036] Furthermore, the receiving channel in each radio frequency antenna link also includes a switch element, and the switch element is used to control the received signal to flow to the ADC through or not through the narrowband filter.

[0037] By connecting the switch element in the receiving channel, the control signal can flow to the ADC through different paths in different working modes. For example, in the sub-band duplex working mode, the control signal flows from the narrowband filter to the ADC, that is, the downlink signal is filtered by the narrowband filter; in the TDD, FDD and other working modes, the control signal flows from the switch element to the ADC without passing through the narrowband filter.

[0038] In combination with the first aspect, in some possible implementations of the first aspect, at least two antenna subarrays among the N antenna subarrays are respectively connected to ADCs on the same receiving channel through phase shifters, and the phase shifters are used to adjust the phase of the uplink signal and the phase of the downlink signal received by the connected antenna subarrays.

[0039] That is to say, multiple antenna subarrays are connected to the same ADC through phase shifters. Since the phases of different antenna subarrays can be adjusted through phase shifters, the uplink signal can be superimposed and enhanced in phase, and the downlink signal can be canceled in reverse by adjusting the phase.

[0040] One possible design is that the N antenna subarrays are respectively connected to the ADC on the same receiving channel through phase shifters, and the ADC on the receiving channel in each of the N RF antenna links is connected to the N antenna subarrays.

[0041] Through the above design, N antenna subarrays can be combined with one receiving channel. In this way, the uplink signal can be enhanced and the downlink signal can be weakened in the same receiving channel by adjusting (or optimizing) the phase of the N antenna subarrays. And the receiving channel in each RF antenna link of the N RF antenna links can achieve uplink signal enhancement and downlink signal weakening in the same way.

[0042] In the application, the goal of adjusting the phase is: through adjustment, the uplink signals are superimposed in phase and the downlink signals are canceled in opposite directions. The uplink signals are superimposed in phase, that is, the uplink signals from different antenna subarrays are superimposed in phase, and the energy is enhanced. The uplink signals from different antenna subarrays are in phase, which can specifically refer to the uplink signals from different antenna subarrays having a phase difference of an integer multiple of 2π. The downlink signals are canceled in opposite directions, that is, the downlink signals from different antenna subarrays cancel in opposite directions and the energy is weakened. The downlink signals from different antenna subarrays are in opposite phase, which can specifically refer to the downlink signals from different antenna subarrays having a phase difference of an odd multiple of π.

[0043] Among them, the uplink signals from different antenna subarrays have a phase difference of an integer multiple of 2π, and the downlink signals from different antenna subarrays have a phase difference of an odd multiple of π, which is an ideal target for phase adjustment. In practical applications, through continuous adjustment and optimization, the phase difference between the uplink signals from different antenna subarrays can be close to an integer multiple of 2π, and the phase difference between the downlink signals from different antenna subarrays can be close to an odd multiple of π.

[0044] In a second aspect, an AAU is provided, which can be applied to a communication device, such as a network device or a terminal device.

[0045] Exemplarily, the AAU includes: N RF antenna links, N is an integer greater than 1; each of the N RF antenna links includes: a transmitting channel, a receiving channel, a feeding network connected to the transmitting channel and the receiving channel, and an antenna subarray connected to the feeding network, the feeding network is used to feed the antenna subarray, and the antenna subarray is used to transmit and receive signals; wherein the receiving channel of each RF antenna link includes an LNA, a narrowband filter and an ADC, the narrowband filter is connected between the LNA and the ADC, and is used to filter other signals except for a preset frequency.

[0046] That is to say, the narrowband filter can allow a signal of a preset frequency to pass through, while filtering signals of other frequencies, so that the interference of the passing signal is small. In the above scheme, by adding a narrowband filter to the receiving channel to filter out the signal, the energy of the interference signal entering the ADC is low, the ADC is less affected by the interference signal, the ADC is not saturated, the receiving link is not blocked as a whole, and the receiving performance is less affected.

[0047] Optionally, the preset frequency is an uplink frequency.

[0048] That is, except for the uplink signal, other signals cannot pass through the narrowband filter. Connecting a narrowband filter in the receiving link is particularly suitable for working modes where the uplink and downlink use different frequency bands, such as the sub-band duplex working mode.

[0049] In combination with the second aspect, in some possible implementations of the second aspect, the receiving channel in each RF antenna link also includes a switching element, and the switching element is used to control the received signal to flow to the ADC through or not through the narrowband filter.

[0050] By connecting the switch element in the receiving channel, the control signal can flow to the ADC through different paths in different working modes. For example, in the sub-band duplex working mode, the control signal flows from the narrowband filter to the ADC, that is, the downlink signal is filtered by the narrowband filter; in the TDD, FDD and other working modes, the control signal flows from the switch element to the ADC without passing through the narrowband filter.

[0051] According to a third aspect, an AAU is provided, which can be applied to a communication device, such as a network device or a terminal device.

[0052] Exemplarily, the AAU includes: N RF antenna links, N is an integer greater than 1; each of the N RF antenna links includes: a transmitting channel, a receiving channel, a feeding network connected to the transmitting channel and the receiving channel, and an antenna subarray connected to the feeding network, the feeding network is used to feed the antenna subarray, and the antenna subarray is used to transmit and receive signals; wherein at least two of the N antenna subarrays are respectively connected to ADCs on the same receiving channel through phase shifters, and the phase shifter is used to adjust the phase of the uplink signal and the phase of the downlink signal received by the connected antenna subarray.

[0053] That is to say, multiple antenna subarrays are connected to the same ADC through phase shifters. Since different antenna subarrays can adjust the phase through phase shifters, it is possible to enhance some signals and weaken some signals by adjusting the phase. Taking network equipment as an example, the enhancement of uplink signals and the weakening of downlink signals are achieved. Among them, the principle of enhancing and weakening signals through phase adjustment can be referred to the relevant description in the first aspect, which will not be repeated here.

[0054] In the above scheme, by connecting multiple antenna subarrays to the same receiving channel through phase shifters respectively, so as to enhance some signals and weaken some signals by adjusting the phase, the energy of the interference signal entering the ADC can be lower, the ADC is less affected by the interference signal, the ADC is not saturated, the receiving link is not blocked as a whole, and the receiving performance is less affected.

[0055] In combination with the third aspect, in some possible implementations of the third aspect, the N antenna subarrays are respectively connected to the ADCs on the same receiving channel through phase shifters, and the ADCs on the receiving channel in each of the N RF antenna links are connected to the N antenna subarrays.

[0056] Through the above design, the N phase shifters connected to the N antenna subarrays can respectively perform phase adjustment (or optimization) on the signals of the antenna subarrays to which they are connected, so that the N receiving channels can respectively enhance the uplink signal and weaken the downlink signal, which is beneficial to improving the receiving performance.

[0057] In a fourth aspect, a communication device is provided, comprising a baseband unit (BBU), and the AAU in any possible implementation of the first to third aspects and the first to third aspects.

[0058] Optionally, the communication device is a network device.

[0059] Optionally, the communication device is a terminal device.

[0060] It should be understood that the fourth aspect of the present application corresponds to the technical solutions of the first to third aspects of the present application, and the beneficial effects achieved by the corresponding feasible implementation methods are similar and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] Figure 1 It is a schematic diagram of the architecture of a communication system to which the communication device provided in the embodiment of the present application is applicable;

[0062] Figure 2 It is a schematic diagram of the TDD working mode;

[0063] Figure 3It is a schematic diagram of FDD working mode;

[0064] Figure 4 It is a schematic diagram of full-duplex working mode;

[0065] Figure 5 It is a schematic diagram of the sub-band duplex working mode;

[0066] Figure 6 It is a schematic diagram of part of the full-duplex working mode;

[0067] Figure 7 is a schematic diagram of a self-interference canceller;

[0068] Figure 8 It is a schematic diagram of a base station architecture with four transmit and four receive;

[0069] Fig. 9 is Figure 8 Schematic diagram of a self-interference canceller used in a base station;

[0070] Fig.10 is a schematic diagram of the radio frequency antenna link in the current AAU;

[0071] Fig.11 is a schematic diagram of an AAU provided in an embodiment of the present application;

[0072] Fig.12 is a schematic diagram of routing of a feed network provided in an embodiment of the present application;

[0073] Fig.13 It is a schematic diagram of reducing interference through different routings of a feed network provided by an embodiment of the present application;

[0074] Fig.14 is a top view of a decoupling unit provided in an embodiment of the present application;

[0075] Fig.15 It is a schematic diagram of the antenna decoupling surface to reduce interference;

[0076] Fig.16 is a schematic diagram of an isolation unit made of scattering material for reducing interference;

[0077] Fig.17 is a schematic diagram of an isolation unit located between antenna subarrays;

[0078] Fig.18 is another schematic diagram of an isolation unit located between antenna subarrays;

[0079] Fig.19 is a schematic diagram of an isolation unit located between antenna subarrays and between antenna elements;

[0080] Fig. 20is another schematic diagram of an isolation unit located between antenna subarrays and between antenna elements;

[0081] Fig.21 is another schematic diagram of an isolation unit located between antenna subarrays and between antenna elements;

[0082] Fig. 22 is another schematic diagram of an isolation unit located between antenna subarrays;

[0083] Fig.23 is another schematic diagram of the AAU provided in an embodiment of the present application;

[0084] Fig.24 is another schematic diagram of the AAU provided in an embodiment of the present application;

[0085] Fig.25 is another schematic diagram of the AAU provided in an embodiment of the present application;

[0086] Fig.26 is another schematic diagram of the AAU provided in an embodiment of the present application;

[0087] Fig. 27 is another schematic diagram of the AAU provided in an embodiment of the present application;

[0088] Fig.28 is another schematic diagram of the AAU provided in an embodiment of the present application;

[0089] Fig.29 is another schematic diagram of the AAU provided in an embodiment of the present application;

[0090] Fig.30 This is another schematic diagram of the AAU provided in an embodiment of the present application. DETAILED DESCRIPTION

[0091] The technical solution in this application will be described below in conjunction with the accompanying drawings.

[0092] To facilitate understanding of the embodiments of the present application, the following points are first explained:

[0093] First, for the convenience of description, this document introduces terms such as "left", "right", "up", and "down" to describe the orientation, and terms such as "horizontal" and "vertical" to describe the direction. It should be understood that these terms are only introduced for the convenience of understanding when describing in conjunction with the accompanying drawings, and should not constitute any limitation to this application. As the direction of the antenna panel changes, such as tilting, flipping, rotating, etc., the orientation of the antenna element and the antenna subarray may change, but this will not affect the relative position relationship between each antenna subarray and each antenna element. Second, in the embodiment of the present application, "at least one" means one or more, and "more" means two or more. "And / or" describes the association relationship of associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone, where A and B can be singular or plural. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship, but it does not exclude the situation where the previous and next associated objects are in an "and" relationship. The specific meaning can be understood in conjunction with the context. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, at least one of a, b, or c can mean: a, b, c; a and b; a and c; b and c; or a, b, and c. A, b, and c can be single or multiple.

[0094] Third, in the embodiments of the present application, the use of prefixes such as "first" and "second" is only to facilitate the distinction and description of different things belonging to the same name category, and does not restrict the order, size or quantity of the things. For example, "first antenna subarray" and "second antenna subarray" are just different antenna subarrays, and do not limit the number or position of the antenna subarrays.

[0095] Fourth, "sending" and "receiving" in the embodiments of the present application refer to the direction of the signal inside the communication device and the air interface. For example, "sending a downlink signal" means that the downlink signal reaches the antenna vibrator through the transmission channel, filter, etc., and then radiates the downlink signal through the antenna vibrator; "receiving an uplink signal" means that the uplink signal is received by the antenna vibrator, and then passes through the filter, receiving channel, etc., and reaches other processing modules inside the communication device, such as the baseband chip.

[0096] Fifth, in the embodiments of the present application, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, or it can be an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present application can be understood according to specific circumstances.

[0097] Sixth, in the embodiments of the present application, multiple examples are given for ease of understanding. In some examples, the network device is described as a communication device configured with the AAU provided by the present application. For the network device, the signal it transmits is a downlink signal, and the signal it receives is an uplink signal. In other examples, the AAU can also be configured in a terminal device. Although no examples are given in this article, technicians in this field can expand other examples based on the same principle. For the sake of brevity, examples will not be given one by one in this article.

[0098] The technical solution provided in this application can be applied to various communication systems, such as: long term evolution (LTE) system, LTE FDD system, LTE TDD, sidelink (SL) communication system, worldwide interoperability for microwave access (WiMAX) communication system, fifth generation (5G) mobile communication system or new radio access technology (NR), satellite communication system, etc. Among them, the 5G mobile communication system can include non-standalone (NSA) and / or standalone (SA).

[0099] The technical solution provided by the present application can also be applied to future communication systems, such as the sixth generation (6G) mobile communication system, or a fusion system of multiple systems, etc. The technical solution provided by the present application can also be applied to device to device (D2D) communication, vehicle to everything (V2X) communication, machine to machine (M2M) communication, machine type communication (MTC), and Internet of things (IoT) communication system or other communication systems.

[0100] A device in a communication system can send a signal to another device or receive a signal from another device. The signal may include information, signaling, or data, etc. The device may also be replaced by an entity, a network entity, a communication device, a communication module, a node, a communication node, etc., and the device is used as an example for description in this application. For example, a communication system may include at least one terminal device and at least one network device. The network device may send a downlink signal to the terminal device, and / or the terminal device may send an uplink signal to the network device. It is understandable that the terminal device in this application may be replaced by a first device, and the network device may be replaced by a second device, and the two perform the corresponding communication method in this application.

[0101] The network device in the present application may be a device with wireless transceiver function. The network device may also be called a radio access network (RAN) device or an access network device. The network device may provide wireless communication function services and may access the terminal device to the wireless network.

[0102] The network device may be a base station. The base station may broadly cover the following various names, or be replaced with the following names, such as: NodeB, evolved NodeB (eNB), next generation NodeB (gNB), relay station, access point, transmitting and receiving point (TRP), transmitting point (TP), master station, auxiliary station, multi-standard wireless (motor slide retainer, MSR) node, home base station, network controller, access node, wireless node, access point (AP), transmission node, transceiver node, baseband unit (BBU), remote radio unit (RRU), active antenna unit (AAU), remote radio head (RRH), central unit (CU), distributed unit (DU), radio unit (RU), positioning node, etc. The base station may be a macro base station, a micro base station, a relay node, a donor node or the like, or a combination thereof, or a wireless controller in a cloud radio access network (CRAN) scenario, a node in an open radio access network (O-RAN or ORAN) scenario, etc. The base station may also refer to a communication module, a modem or a chip used to be arranged in the aforementioned device or apparatus. The base station may also be a mobile switching center and a device that performs the base station function in D2D, V2X, and M2M communications, a network side device in a 6G network, and a device that performs the base station function in a future communication system. The base station may support networks with the same or different access technologies. Optionally, the RAN node may also be a server, a wearable device, a vehicle or an on-board device, etc. For example, the access network device in the vehicle to everything (V2X) technology may be a road side unit (RSU). The embodiments of the present application do not limit the specific technology and specific device form adopted by the network device.In some deployments, the network device mentioned in the embodiments of the present application may be a device including a CU, or a DU, or a device including a CU and a DU, or a control plane CU node (central unit control plane (central unit-control plane, CU-CP)) and a user plane CU node (central unit user plane (central unit-user plane, CU-UP)) and a DU node. For example, the network device may include a gNB-CU-CP, a gNB-CU-UP, and a gNB-DU.

[0103] In some deployments, multiple RAN nodes collaborate to assist the terminal in achieving wireless access, and different RAN nodes implement part of the functions of the base station. For example, the RAN node can be a CU, DU, CU-CP, CU-UP, or RU. The CU and DU can be set separately, or can also be included in the same network element, such as a BBU. The RU can be included in a radio frequency device or a radio frequency unit, such as an RRU, AAU, or RRH.

[0104] The RAN node may support one or more types of fronthaul interfaces, and different fronthaul interfaces correspond to DUs and RUs with different functions. If the fronthaul interface between the DU and the RU is a common public radio interface (CPRI), the DU is configured to implement one or more baseband functions, and the RU is configured to implement one or more radio frequency functions. If the fronthaul interface between the DU and the RU is another interface, relative to the CPRI, part of the downlink and / or uplink baseband functions, such as, for downlink, one or more of precoding, digital beamforming (BF), or inverse fast Fourier transform (IFFT) / cyclic prefix (CP) are moved from the DU to the RU for implementation, and for uplink, one or more of digital beamforming (BF), or fast Fourier transform (FFT) / cyclic prefix (CP) are moved from the DU to the RU for implementation. In a possible implementation, the interface may be an enhanced common public radio interface (eCPRI). In the eCPRI architecture, the division between DU and RU is different, corresponding to different types (category, Cat) of eCPRI, such as eCPRI Cat A, B, C, D, E, F.

[0105] Taking eCPRI Cat A as an example, for downlink transmission, based on layer mapping, the DU is configured to implement layer mapping and one or more functions before it (i.e., coding, rate matching, scrambling, modulation, and one or more functions of layer mapping), while other functions after layer mapping (e.g., RE mapping, digital beamforming, or one or more functions of IFFT / adding CP) are moved to the RU for implementation. For uplink transmission, based on RE demapping, the DU is configured to implement demapping and one or more functions before it (i.e., decoding, derate matching, descrambling, demodulation, IDFT, channel equalization, and one or more functions of RE demapping), while other functions after demapping (e.g., one or more functions of digital BF or FFT / de-CP) are moved to the RU for implementation. It can be understood that for the functional description of DU and RU corresponding to various types of eCPRI, please refer to the eCPRI protocol, which will not be repeated here.

[0106] In one possible design, the processing unit for implementing the baseband function in the BBU is called a baseband high layer (BBH) unit, and the processing unit for implementing the baseband function in the RRU / AAU / RRH is called a baseband low layer (BBL) unit.

[0107] In different systems, CU (or CU-CP and CU-UP), DU or RU may also have different names, but those skilled in the art can understand their meanings. For example, in the ORAN system, CU may also be called O-CU (open CU), DU may also be called O-DU, CU-CP may also be called O-CU-CP, CU-UP may also be called O-CU-UP, and RU may also be called O-RU. Any unit in the CU (or CU-CP, CU-UP), DU and RU in this application may be implemented by a software module, a hardware module, or a combination of a software module and a hardware module.

[0108] In the embodiments of the present application, the device for realizing the function of the network device may be a network device; or it may be a device capable of supporting the network device to realize the function, such as a chip system, a hardware circuit, a software module, or a hardware circuit plus a software module. The device may be installed in the network device or used in combination with the network device. In the embodiments of the present application, only the device for realizing the function of the network device is a network device as an example for explanation, and the scheme of the embodiments of the present application is not limited.

[0109] The terminal device in this application may also be referred to as user equipment (UE), access terminal, user unit, user station, mobile station, mobile station, remote station, remote terminal, mobile equipment (ME), user terminal, terminal, wireless communication device, user agent or user device.

[0110] The terminal device may be a device that can provide voice / data connectivity, for example, a handheld device with wireless connection function, a vehicle-mounted device, etc. At present, some examples of terminal devices may be: mobile phones, tablet computers (pad), computers with wireless transceiver functions (such as laptops, PDAs, etc.), mobile internet devices (mobile internet devices, MIDs), virtual reality (virtual reality, VR) devices, augmented reality (augmented reality, AR) devices, wireless terminals in industrial control, wireless terminals in self-driving, drones, wireless terminals in remote medical, wireless terminals in smart grids, wireless terminals in transportation safety, wireless terminals in smart cities, wireless terminals in smart homes, cellular phones, cordless phones, session initiation protocol (session initiation protocol, SIP) phones, wireless local loop (wireless local loop, WLL) stations, personal digital assistants (personal digital assistants) assistant, PDA), handheld devices with wireless communication function, computing devices or other processing devices connected to a wireless modem, vehicle-mounted devices, wearable devices, terminal devices in 5G networks or terminal devices in future evolved public land mobile communication networks (public land mobile network, PLMN), etc.

[0111] Among them, wearable devices can also be called wearable smart devices, which are a general term for the intelligent design and development of wearable devices for daily wear using wearable technology, such as glasses, gloves, watches, clothing and shoes. Wearable devices are portable devices that are worn directly on the body or integrated into the user's clothes or accessories. Wearable devices are not only hardware devices, but also realize powerful functions through software support, data interaction, and cloud interaction. Broadly speaking, wearable smart devices include full-featured, large-sized, and independent of smartphones to achieve complete or partial functions, such as smart watches or smart glasses, as well as those that only focus on a certain type of application function and need to be used in conjunction with other devices such as smartphones, such as various smart bracelets and smart jewelry for vital sign monitoring.

[0112] In addition, the terminal device can also be a terminal device in the IoT system, which can also be called an IoT node. IoT is an important part of the future development of information technology. Its main technical feature is to connect objects to the network through communication technology, thereby realizing an intelligent network of human-machine interconnection and object-to-object interconnection. The connection can be through broadband technology or narrowband technology. IoT technology can achieve massive connections, deep coverage, and terminal power saving through narrowband (NB) technology, for example.

[0113] In addition, terminal devices can also include sensors such as smart printers, train detectors, and gas stations. Their main functions include collecting data (part of the terminal equipment), receiving control information and downlink data from network devices, and sending electromagnetic waves to transmit uplink data to network devices.

[0114] The terminal device in the present application may be a virtualized device, for example, implemented by general hardware and instantiated virtualization functions, or by dedicated hardware and instantiated virtualization functions. The general hardware may be a server, for example, a cloud server.

[0115] Figure 1 FIG. 1 is a schematic diagram of the architecture of a communication system 10 to which the communication device provided in the embodiment of the present application is applicable. Figure 1 As shown, the communication system 10 includes a wireless access network 100 and a core network 200. Optionally, the communication system 10 also includes the Internet 300. The wireless access network 100 may include at least one wireless access network device (such as Figure 1 110a and 110b), and may also include at least one terminal device (such as Figure 1 120a-120j in FIG. 120b). The terminal device can be connected to the wireless access network device in a wireless manner. The terminal devices and the wireless access network devices can be connected to each other in a wired or wireless manner. Figure 1This is just a schematic diagram. The communication system 10 may also include other network devices, such as wireless relay devices and wireless backhaul devices. Figure 1 Not drawn in.

[0116] The wireless access network device may be a base station deployed in the air, such as a satellite base station 110a; or a base station deployed indoors, such as a micro base station or an indoor station 110b. It should be understood that the present application does not limit the specific technology and specific device form used by the wireless access network device. For ease of description, the following description takes a base station as an example of a wireless access network device.

[0117] The terminal device may be a terminal device deployed in the air, such as Figure 1 The helicopter or drone 120i in the figure can also be a terminal device deployed on the ground, such as Figure 1 The mobile phones 120a, 120e, 120f and 120j, the vehicle 120b, the computer 110b, the printer 120h, etc.

[0118] Base stations and terminals can be fixed or movable. Base stations and terminals can be deployed on land, including indoors or outdoors, handheld or vehicle-mounted; they can also be deployed on the water surface; they can also be deployed on aircraft, balloons, and artificial satellites in the air. The embodiments of this application do not limit the application scenarios of base stations and terminals.

[0119] Base stations and terminals, base stations and base stations, and terminals and terminals can communicate through authorized spectrum, unauthorized spectrum, or both; they can communicate through spectrum below 6 gigahertz (GHz), spectrum above 6 GHz, or spectrum below 6 GHz and spectrum above 6 GHz. The embodiments of the present application do not limit the spectrum resources used for wireless communication.

[0120] There are many working modes in current communication systems, such as TDD, FDD, full duplex, sub-band duplex, partial full duplex, etc. The following will briefly describe the above working modes in conjunction with the accompanying drawings.

[0121] Figure 2 Figure 1 is a schematic diagram of the TDD working mode. As shown in the figure, in the TDD working mode, the network device sends and receives signals on all frequency bandwidths of f0. For example, the network device can Figure 2 The downlink signal is sent in the downlink time slot indicated by the blank box in the middle. The uplink signal is received in the uplink time slot shown in the box. Correspondingly, the terminal device receives the downlink signal in the downlink time slot and sends the uplink signal in the uplink time slot. It should be understood that Figure 2 The ratio of uplink time slot to downlink time slot is shown as 1:4, which is just one possible ratio of uplink and downlink time slots. TDD may also have other time slot ratios, which is not limited in this application.

[0122] Figure 3 is a schematic diagram of the FDD working mode. As shown in the figure, in the FDD working mode, the network equipment uses all time slots (such as Figure 3 The downlink signal is sent in all time slots on the f2 frequency bandwidth (such as Figure 3 With fill pattern ) receives uplink signals. Accordingly, the terminal device receives downlink signals in all time slots on the f1 frequency bandwidth and sends uplink signals in all time slots on the f2 frequency bandwidth. Among them, f1 can be called a downlink frequency, and f2 can be called an uplink frequency.

[0123] Figure 4 is a schematic diagram of full-duplex working mode. The network equipment is in all time slots on all frequency bandwidths of f0 (such as Figure 4 With fill pattern The full-duplex working mode can reuse frequency resources and improve frequency efficiency, but because network devices send and receive signals on the same time-frequency resources, there will be serious interference problems.

[0124] Figure 5 is a schematic diagram of the sub-band duplex working mode. The sub-band duplex working mode can be regarded as a variation of the TDD working mode. In the sub-band duplex working mode, all time slots on a small part of the frequency bandwidth f3 in the frequency bandwidth f0 are uplink time slots, such as Figure 5 The pattern with fill corresponding to frequency f3 As shown in the box, the network device can receive uplink signals in all time slots on the f3 frequency bandwidth, and the terminal device can send uplink signals in all time slots on the f3 frequency bandwidth; in the f0 frequency bandwidth, excluding the f3 frequency bandwidth, the uplink and downlink time slots are still divided according to the TDD working mode. For example, the network device can Figure 5 The downlink signal is sent in the downlink time slot indicated by the blank box in the middle. Correspondingly, the terminal device receives the downlink signal in the downlink time slot and sends the uplink signal in the uplink time slot.

[0125] Sub-band duplex working mode can improve uplink coverage and enhance the signal-to-noise ratio of uplink signals, that is, enhance the signal-to-noise ratio of signals sent by terminal devices to network devices. Figure 4 The full-duplex working mode shown is similar, network devices can send and receive signals on the same time-frequency resources, and there is severe interference. Although the frequency of the received signal is different from the frequency of the transmitted signal, the downlink signal will also be coupled to the receiving channel, and because the transmission power of the downlink signal is large, the receiving channel will be blocked, thereby reducing the receiving channel performance.

[0126] Figure 6 This is a schematic diagram of the partial full-duplex working mode. The time and frequency resources of partial full-duplex are a fusion of sub-band duplex, full-duplex, and TDD working modes. As shown in the figure, in the f0 frequency bandwidth, the time slots on the partial frequency bandwidth are divided into uplink and downlink time slots according to TDD, such as Figure 6 The time-frequency resources in are shown from the first row to the sixth row from top to bottom; all time slots on a part of the frequency bandwidth are uplink time slots, such as Figure 6 The time-frequency resources in are shown in the second and fifth rows from top to bottom; all time slots on some frequency bandwidths are full-duplex time slots, such as Figure 6 As shown in the fourth row from top to bottom in the time-frequency resources in FIG. 1 , the time slots on a part of the frequency bandwidth are switched between downlink time slots, uplink time slots and full-duplex time slots over time, as shown in FIG. Figure 6 The time-frequency resources in are shown in the third row from top to bottom.

[0127] It should be noted that any receiver has a certain receiving dynamic range. When the receiving power exceeds the maximum power allowed by the receiving dynamic range, the nonlinear device of the receiver will be saturated, resulting in nonlinear distortion, which will cause multi-order products of intermodulation and cross-modulation. This is receiver blocking, which will cause the receiver to not work properly. Receiver blocking may also occur in the receiving channel, that is, receiving channel blocking. Accordingly, this interference is called blocking interference.

[0128] In certain working modes, such as full-duplex, sub-band duplex, partial full-duplex and other working modes, network devices can use the same group or multiple groups of antenna units to transmit and receive signals at the same time, that is, share the same antenna for transmission and reception. Shared antenna for transmission and reception means sharing the same group or multiple groups of antenna units for transmission and reception, where a group of antenna units can include one or more antenna units. When sharing the same antenna for transmission and reception, there may be a situation where the receiving channel is blocked. In order to prevent the receiving channel from being blocked, a self-interference canceller is usually used to reduce the interference of the downlink signal received by the receiving channel. The self-interference canceller aims to construct an RF signal with the same amplitude and opposite phase as the interference signal, and synthesize it with the interference signal, thereby forming a canceling effect on the interference signal. Figure 7 is an example of a self-interference canceller. Figure 7As shown, the self-interference canceller may include multiple links, each tap link includes components such as an adjustable phase shifter and an adjustable attenuator, and the circuit complexity is high.

[0129] At present, the common base station architectures with a common antenna for transmission and reception include one transmission and one reception, two transmissions and two receptions, four transmissions and four receptions, etc. Taking four transmissions and four receptions as an example, the base station uses four sets of antenna units to transmit signals and can also use these four sets of antenna units to receive signals. Figure 8 This is a schematic diagram of a base station architecture with four transmit and four receive signals. Figure 8 From left to right, four RF antenna links are shown, each of which includes a transmitting channel, a receiving channel, an antenna shared by the transmitting channel and the receiving channel, and a filter and a circulator connected between the transmitting channel, the receiving channel and the antenna. In order from left to back, the four antenna subarrays are respectively recorded as antenna b1, antenna b2, antenna b3, and antenna b4; the four transmitting channels are respectively recorded as the first transmitting channel, the second transmitting channel, the third transmitting channel, and the fourth transmitting channel; the four receiving channels are respectively recorded as the first receiving channel, the second receiving channel, the third receiving channel, and the fourth receiving channel; the four RF antenna links are respectively recorded as the first RF antenna link, the second RF antenna link, the third RF antenna link, and the fourth RF antenna link.

[0130] Taking the first RF antenna link as an example, due to the isolation limitation of the circulator, a part of the downlink signal transmitted by the first transmitting channel (for example, denoted as a1) will be coupled from the circulator in the link to the first receiving channel; another part of the component (for example, denoted as a2) will enter the circulator after being reflected from the input port of the filter in the link, and then enter the first receiving channel; another part of the component (for example, denoted as a3) will enter the filter and circulator in the link after being reflected from the input port of antenna b1, and then enter the first receiving channel; another part of the downlink signal components, such as the downlink signal component transmitted by the second transmitting channel (for example, denoted as a4), the downlink signal component transmitted by the third transmitting channel (for example, denoted as a5) and the downlink signal component transmitted by the fourth transmitting channel (for example, denoted as a6) are respectively coupled from the antennas b2, b3 and b4 connected to them to the antenna b1, and then enter the first receiving channel through the filter and circulator in the first RF antenna link. Since the power of these downlink signal components a1 to a6 is still relatively large when entering the first receiving channel, the first receiving channel will be blocked, thereby affecting the receiving performance. By analogy, the second receiving channel, the third receiving channel and the fourth receiving channel will also receive similar components of the downlink signal, resulting in blocking of each receiving channel and affecting the receiving performance.

[0131] If the aforementioned self-interference canceller is used to suppress the blocking of each receiving channel, a self-interference canceller needs to be used between each receiving channel and each transmitting channel to reduce interference. Fig. 9Shown in Figure 8 An example of a self-interference canceller is shown in the base station architecture. Fig. 9 As shown, a self-interference canceller is connected between the first transmitting channel and the first receiving channel, the second receiving channel, the third receiving channel, and the fourth receiving channel; a self-interference canceller is also connected between the second transmitting channel and the first receiving channel, the second receiving channel, the third receiving channel, and the fourth receiving channel; a self-interference canceller is also connected between the third transmitting channel and the first receiving channel, the second receiving channel, the third receiving channel, and the fourth receiving channel; a self-interference canceller is also connected between the fourth transmitting channel and the first receiving channel, the second receiving channel, the third receiving channel, and the fourth receiving channel. In summary, in order to prevent the receiving channel from being blocked, the base station uses a total of 16 self-interference cancellers, forming a 4×4 fully connected network.

[0132] As the number of antenna units shared by both transmitting and receiving increases, the value of N also tends to increase, the number of self-interference cancellers increases dramatically, and the circuit complexity also increases dramatically.

[0133] In view of this, the present application provides an AAU, which adopts isolation technology between different RF antenna links and provides multiple solutions for isolation technology, such as optimizing the design of the feed network to make the amplitude and / or phase of the signals of different links different, thereby reducing the near-field energy of the receiving antenna; for example, using an antenna decoupling surface (ADS) above the antenna subarray to reduce the signal interference between the antenna subarrays; for example, using isolation units such as absorbing materials, scattering materials, and metamaterials between adjacent antenna subarrays to reduce the signal interference between the antenna subarrays, etc. Between the transmitting channel and the receiving channel in the same RF antenna link, a self-interference canceller can be used to eliminate the signal interference of this link. In this way, in addition to using a self-interference canceller in this link to eliminate interference, the interference between different links can be eliminated by other means, the use of self-interference cancellers is greatly reduced, and the complexity is also greatly reduced.

[0134] For ease of understanding and explanation, before introducing the embodiments of the present application, a brief explanation of the terms involved in this document is first given.

[0135] 1. AAU: The main equipment of 5G base stations, it is the implementation plan of large-scale antenna arrays. AAU can be regarded as a combination of remote radio unit (RRU) and antenna.

[0136] 2. Antenna subarray: In this application, in order to distinguish antenna elements connected to different RF channels (including transmit channels and receive channels), antenna elements connected to the same RF channel are defined as an antenna subarray. The same antenna subarray is connected to the same RF channel, and different antenna subarrays are connected to different RF channels.

[0137] 3. Antenna vibrator: It can also be called vibrator or radiation unit. It is the most basic unit of the antenna. Antenna vibrator is made of conductive metal. When alternating current flows on the wire, electromagnetic wave radiation can occur. Therefore, antenna vibrator can also be called radiator, radiation unit, etc.

[0138] 4. Feed network: It can also be called a power distribution unit. In this application, the feed network is used to feed the connected antenna subarray (specifically, it can refer to the antenna element in the antenna subarray). The feed network can feed the RF signal to the antenna subarray according to a certain amplitude and phase, or send the wireless signal received by the antenna subarray to the signal processing unit inside the communication device according to a certain amplitude and phase.

[0139] 5. Antenna: including a reflector (also called a base plate), a feed network and an antenna vibrator. Optionally, the antenna also includes a radome. For ease of understanding and explanation, this document mainly shows the antenna vibrator and the feed network, as well as the RF channel connected to the feed network, in conjunction with the accompanying drawings, while other components such as the reflector and the radome are not shown. However, this should not constitute any limitation to the present application. The present application does not limit the structure of the antenna and the shape of the antenna vibrator.

[0140] It should be understood that the specific structure of the antenna and its working principle can be found in the existing technology, and this application will not describe them in detail.

[0141] The technical solution of the present application will be described in detail below with reference to the accompanying drawings.

[0142] For ease of understanding, first combine Fig.10 Provides information about the current RF antenna link.

[0143] Fig.10 This is a schematic diagram of the RF antenna link in the current AAU. Fig.10As shown, in the order from the antenna subarray to the back, each RF antenna link includes: an antenna subarray, a feed network, a filter, a circulator, a transmitting channel and a receiving channel. Among them, the transmitting channel and the receiving channel are connected to the circulator, the circulator is connected to the filter, and the filter is connected to the antenna subarray through the feed network. The circulator, also known as a circulator, is a multi-port device used to transmit electromagnetic waves incident from any port to the next port in the direction sequence determined by the static bias magnetic field, and can transmit high-frequency signal energy in one direction. In the AAU, the circulator can transmit the signal from the transmitting channel (such as a downlink signal) to the filter, and can also transmit the signal from the filter (such as an uplink signal) to the receiving channel. The filter can be used to effectively filter out the frequency point of a specific frequency in the power line or the frequency outside the frequency point, obtain a power signal of a specific frequency, or eliminate a power signal of a specific frequency. In the AAU, the filter can filter the noise of the signal flowing through to a certain extent. The feeding network can feed the antenna subarray through the RF line. The RF line includes stripline or microstrip line feeding. By designing the RF line, such as the width and / or length, the feeding network can feed the signal from the transmitting channel to the antenna subarray at a certain phase and amplitude, or feed the signal from the antenna subarray to the filter at a certain phase and amplitude.

[0144] The antenna subarray includes one or more antenna elements, which are arranged according to a certain rule to form a subarray. The antenna subarray shown in the figure includes 6 antenna elements. The 6 antenna elements are connected to the same filter through a feed network, as shown in the figure, so it can be called one drives six.

[0145] It should be understood that the quantitative relationship between the filter and the antenna element in the figure is only an example. In actual applications, one filter can be connected to a larger or smaller number of antenna elements, for example, one drive three, one drive four, one drive nine, etc. Multiple antenna elements can also be divided into more groups, for example, 9 antenna elements are divided into three groups and connected to the filter. This application does not limit this.

[0146] Further, as shown in the figure, the transmission channel includes: a power amplifier (PA), a radio frequency driver (Drv) amplifier (shown as Drv in the figure), a digital-to-analog converter (DAC), etc. Among them, the DAC is used to convert the digital signal to be transmitted in the transmission channel into an analog signal, and the PA is used to amplify the power of the signal.

[0147] The receiving channel includes: LNA and ADC, etc. LNA is used to eliminate noise, and ADC is used to convert the received digital signal into an analog signal.

[0148] It should be understood that Fig.10 The components included in the RF antenna chain shown are only examples, and the RF antenna chain may also include other components, or other components that can be used to achieve the same or similar functions may be used to replace the components. Fig.10 One or more devices in the present application are not limited to this.

[0149] It should be noted that in Fig.10 And later Fig.11 , Figures 23 to 30 In the RF antenna link shown, each antenna subarray is connected to a RF channel, and each antenna subarray can be driven by the connected RF channel. For the sake of brevity, the following description will not be repeated.

[0150] Fig.11 Schematic diagram of the AAU provided in the embodiment of the present application. Fig.11 As shown, the AAU includes: N (N is an integer greater than 1) radio frequency antenna links. Each radio frequency antenna link includes an antenna subarray. In other words, the N radio frequency antenna links include N antenna subarrays. The N radio frequency antenna links correspond to the N antenna subarrays one by one. It is not difficult to see that Fig.10 The components included in the RF antenna chain are Fig.11 The same device can be found in Fig.10 The relevant instructions will not be repeated here.

[0151] Fig.11 An example is shown where N is 2. As shown in the figure, the two antenna subarrays of the two RF antenna links are respectively shown as antenna subarray 1 and antenna subarray 2 in the figure. By designing different routings for the feed networks in the two RF antenna links and / or providing isolation components in the antenna subarrays, interference between the antenna subarrays can be reduced.

[0152] Among them, the routing of the feed network of different RF antenna links is different, which may specifically refer to the different layouts of the RF circuits in the PCB in different RF antenna links. The different layouts of the RF circuits may include: different lengths of the RF circuits, and / or different widths of the RF circuits. As an example and not a limitation, the RF circuit includes a microstrip line or a stripline. For the convenience of explanation, this article will record the design scheme of different routings of the feed network of different RF antenna links as Scheme 1.

[0153] For ease of understanding, Fig.12 The feeding networks in different RF antenna chains are shown. Fig.12The feed network shown is the routing of the feed network in 8 RF antenna links. Each RF antenna link corresponds to a horizontal routing in the figure, and the 8 RF antenna links correspond to the 8 horizontal routings in the figure.

[0154] Fig.12 There are slight differences between the 8 traces shown. Fig.12 As shown at a of the feed network 2 and b of the feed network 4, the line length shown at b is greater than the line length shown at a, which means that the lengths of the RF lines of the feed network 2 and the RF lines of the feed network 4 at this position are different; the line shown at b is also thicker than the line shown at b, which means that the widths of the RF lines of the feed network 2 and the RF lines of the feed network 4 at this position are also different. It is not difficult to find out through careful observation that Fig.12 The routing of the eight RF lines shown in the figure is not exactly the same. Through different routing designs, the phases of the signals transmitted by the eight RF antenna links can be different, so that the signals tend to have opposite phases in the near field and the energy cancels out.

[0155] For the convenience of explanation, the following description takes the network device configured with the AAU as an example. For the downlink signal transmitted by the antenna subarray, other antenna subarrays in its vicinity can be regarded as receivers, so the multiple antenna subarrays are distinguished and named as the transmitter antenna subarray and the receiver antenna subarray in the following description. It can be understood that each antenna subarray can be a transmitter antenna subarray or a receiver antenna subarray. Sending or receiving is relative to the signal.

[0156] Fig.13 This is a schematic diagram of reducing interference through different routing of the feed network. Fig.13 The routing of the feed network of the transmitter antenna subarray is different from that of the receiver antenna subarray. By designing different routings for the feed networks in different RF antenna links, on the one hand, when the transmitter antenna subarray transmits a downlink signal, the downlink signals received by different antenna elements of the receiver antenna subarray in the near field of the transmitter antenna subarray are in opposite phases, vector-cancelled, and the energy is reduced. Therefore, the energy of the downlink signal received by the receiver antenna subarray is reduced, interference is reduced, and the downlink signals received by the antenna in the far field (such as the terminal antenna) are in the same phase and have superimposed energy. On the other hand, by designing the feed network of the receiver antenna subarray, each antenna element in the receiver antenna subarray can further vector-cancel in the circuit domain after receiving the downlink signal, for example Fig.13 The downlink signals ① and ② with opposite phases are received by different antenna elements, so that the energy of the downlink signal is further reduced and the interference is further reduced.

[0157] It should be understood that Fig.12The feed networks in the eight RF antenna links shown are only examples. In actual design, technicians can continuously optimize the routing of the feed networks through multiple tests to achieve the above two purposes. Therefore, there may be cases where the feed networks in the eight RF links are partially different. In other words, when N is greater than 2, the routing of the feed networks of at least two RF antenna links among the N RF antenna links is different.

[0158] In addition to the different routing designs for the feed network, this solution also provides a solution for setting up isolation components to reduce interference between antenna subarrays.

[0159] One design of the isolation component is an antenna decoupling surface (ADS). Optionally, the isolation component includes M decoupling units located above N antenna subarrays. The number M of decoupling units can be a multiple of the number N of antenna subarrays, for example, M=N, or M=αN, where α is a non-zero coefficient. The M decoupling units can be evenly arranged and covered above the antenna element. The M decoupling units are combined together to form an antenna decoupling surface as a whole. The antenna decoupling surface can reflect part of the received signal to reduce interference. For the convenience of explanation, this article will record the design scheme of setting an antenna decoupling surface above N antenna subarrays as Scheme 2.

[0160] Fig.14 is a top view of the decoupling unit. Fig.14 (a) to (h) show decoupling units of different shapes. However, it should be understood that Fig.14 The above is only an example, and the present application does not limit the shape of the decoupling unit. In the embodiment of the present application, the M decoupling units above the N antenna subarrays can be decoupling units of the same shape.

[0161] Fig.15 It is a schematic diagram of the antenna decoupling surface to reduce interference. Fig.15Antenna subarrays A, B, C, and D are shown. For ease of understanding and explanation, this article takes the interference of antenna subarrays A and B on antenna subarray C as an example to describe the role of the decoupling surface. When antenna subarray A transmits a signal, the transmitted signal can propagate in different directions, such as but not limited to the paths shown in ① and ④ in the figure. Among them, a part of the signal propagating along path ① can continue to propagate outward through the decoupling surface, as shown in path ② in the figure, and the other part is reflected by the decoupling surface and returns to antenna subarray A along path ③. After the signal propagating along path ④ reaches the decoupling surface, it may be reflected by the decoupling surface and reach antenna subarray C along path ⑤, causing interference to the receiving channel of antenna subarray C. In addition, the signal transmitted by antenna subarray B can also propagate in different directions, such as but not limited to the paths shown in ⑥ and ⑧ in the figure. Among them, after the signal propagated along path ⑥ reaches the decoupling surface, it may be reflected by the decoupling surface and reach the antenna subarray C along path ⑦, causing interference to the receiving channel of antenna subarray C; the signal propagated along path ⑧ may also reach the antenna subarray C, for example, it may be directly coupled or transmitted to the receiving channel of antenna subarray C, causing interference to the receiving channel of antenna subarray C.

[0162] besides, Fig.15 The antenna subarray D in Fig.15 Other antenna subarrays not shown in the figure may also cause interference to antenna subarray C.

[0163] Since the phases of the interference signals reaching the antenna subarray C along different paths are likely to be different, by designing the relative position of the decoupling surface and the antenna subarray, the energy of these interference signals can be reduced based on the principle of opposite phases and energy cancellation, thereby reducing the interference to the receiving channel of the antenna subarray C. One possible design is that the distance between the decoupling surface and the upper surface of the antenna subarray (such as Fig.15 The h) shown in FIG. 1 is one quarter of the wavelength of the electromagnetic wave signal.

[0164] Understandably, Fig.15 The example of the decoupling surface is just to take the interference signal between three antenna subarrays as an example to describe the role of the decoupling surface. In actual applications, antenna subarray C may be interfered by the signal transmitted by more antenna subarrays. And each antenna subarray in the antenna array may also be interfered by the signal transmitted by more antenna subarrays. Fig.15 Like the world subarray C in the figure, it is interfered by the signals emitted by one or more other antenna subarrays around it. Therefore, the decoupling surface can also be applied to a larger range, such as the N antenna subarrays in this solution, to reduce the interference between different antenna subarrays. For example, the decoupling surface above an antenna subarray (referred to as the first antenna subarray) between the N antenna subarrays can reflect part of the signals from other antenna subarrays, thereby canceling the signals from other antenna subarrays in the receiving channel connected to the first antenna subarray.

[0165] It should be noted that since the antenna decoupling surface is located above the antenna subarray, Fig.11 and later Fig.23 It is not shown in the figure for the convenience of illustration, but this shall not constitute any limitation to the present application.

[0166] Another design of the isolation component is to set an isolation unit made of absorbing material, scattering material or metamaterial between the antenna subarrays. For the convenience of description, this paper will record the design scheme of setting an isolation unit between N antenna subarrays as scheme three.

[0167] Among them, absorbing materials can absorb or weaken the electromagnetic wave energy received on their surface, so they can be used to prepare isolation units. Scattering materials and metamaterials can both regulate the amplitude and phase of electromagnetic waves and change their scattering or reflection paths to achieve the effect of canceling downlink signals, so they can be used to prepare isolation units.

[0168] In the present application, each isolation unit can be made of one of absorbing materials, scattering materials, and metamaterials. In the case where the isolation assembly includes multiple isolation units, different isolation units can be made of the same material, such as one of absorbing materials, scattering materials, and metamaterials; different isolation units can also be made of different materials, such as any two or three of absorbing materials, scattering materials, and metamaterials.

[0169] As an example, Fig.16 Schematic diagram of an isolation unit made of scattering material for reducing interference. Fig.16 The figure shows an isolation unit located between two antenna elements A and B. The isolation unit is located near the midpoint between the two antenna elements and is placed parallel to the reflector. Since the isolation unit is made of scattering material, the signal from antenna element A is scattered by the isolation unit, so that part of the signal originally propagated through path 1 is propagated through path 2, and the signal component of path 1 and the signal component of path 2 have equal amplitude and opposite phase. In this way, the signal can be offset, reducing the interference to antenna element B.

[0170] It should be understood that Fig.16 This is only an example, and the present application does not limit the number and position of the isolation units.

[0171] Optionally, the isolation component includes at least one isolation unit located between adjacent antenna subarrays in the N antenna subarrays, and the at least one isolation unit is used to isolate interference signals between at least part of the antenna subarrays in the N antenna subarrays.

[0172] Fig.17 is a schematic diagram of the isolation unit located between antenna subarrays. Fig.17Eight antenna subarrays are shown, as indicated by the hollow boxes marked by A, B, C, D, E, F, G, and H in the figure. An isolation unit is provided between every two adjacent antenna subarrays, as indicated by the solid boxes in the figure. It can be seen that the isolation unit is located between adjacent antenna subarrays. For example, at the junction of antenna subarray A and antenna subarray B, at the junction of antenna subarray B and antenna subarray C, etc. in the figure, an isolation unit is provided between every two adjacent antenna elements in the horizontal direction (it should be understood that the two antenna elements are antenna elements in different subarrays); for another example, at the junction of antenna subarray A and antenna subarray E, at the junction of antenna subarray B and antenna subarray F, an isolation unit is also provided between every two adjacent antenna elements in the vertical direction (it should be understood that the two antenna elements are antenna elements in different subarrays).

[0173] Therefore, these isolation units can be used to isolate interference signals between different antenna subarrays, such as interference signals between antenna subarray A and antenna subarray B, interference signals between antenna subarray A and antenna subarray C, interference signals between antenna subarray A and antenna subarray E, and so on.

[0174] It should be understood that the antenna element is not limited to Fig.17 Used in the antenna shown, the antenna element can also be an antenna element in a dual-polarized antenna, or an antenna element in an antenna of other forms.

[0175] Fig.18 is another schematic diagram of the isolation unit located between antenna subarrays. Fig.18 The figure shows antenna elements in a dual-polarized antenna with 6 rows and 6 columns. The antenna elements in each column with the same polarization direction belong to a subarray, and each column includes two subarrays with different polarization directions. Fig.17 A total of 12 antenna subarrays are shown, namely A, B, C, D, E, F, G, H, I, J, K, and L in the figure.

[0176] It should be noted that the dual-polarized antenna can also be called a cross-polarized antenna. The dual-polarized antenna includes two antenna elements with different polarization directions. Each dual-polarized antenna can be in a cross shape, and the two cross-distributed (or placed) antenna elements can form a dual-polarized radiation of ±45°. The polarization direction of one antenna subarray is +45°, and the polarization direction of the other antenna subarray is -45°; or, the polarization direction of one antenna subarray is horizontal polarization, and the polarization direction of the other antenna subarray is vertical polarization. This application is not limited to this. Since the antenna elements in the two antenna subarrays are used to form a dual-polarized antenna, there are some limitations on the setting of an isolation unit between the two antenna subarrays that constitute the dual-polarized antenna. However, the interference between the antenna subarrays can be reduced by designing different routings for the feeding networks in the two RF links, and / or by setting a decoupling unit above the antenna subarray.

[0177] In this embodiment, for the convenience of description and distinction, two subarrays constituting a dual-polarized antenna subarray are recorded as a group of antenna subarrays. Fig.17 A total of 6 groups of antenna subarrays are shown, and isolation units are provided between the groups. These isolation units can be located between two adjacent groups of antenna subarrays, and specifically between two adjacent groups of antenna elements in the horizontal direction, as shown by the solid boxes in the figure. These isolation units can be used to isolate interference signals between different groups of antenna subarrays, for example, interference signals between antenna subarrays A and B and antenna subarrays C and D, interference signals between antenna subarrays A and B and antenna subarrays E and F, interference signals between antenna subarrays C and D and antenna subarrays E and F, and so on, which are not listed here.

[0178] It can be understood that, when the antenna in the AAU is a dual-polarization antenna, N is an even number.

[0179] Furthermore, the isolation component further includes: at least one isolation unit located between adjacent antenna elements, the at least one isolation unit being used to isolate interference signals between the antenna elements. For ease of explanation, the design scheme of providing an isolation unit between the antenna elements herein can be regarded as an optional scheme provided on the basis of scheme three.

[0180] That is to say, the isolation component can be used not only to isolate interference signals between different antenna subarrays, but also to isolate interference signals between different antenna elements.

[0181] Fig.19 and Fig. 20 It is a schematic diagram of the isolation unit located between antenna subarrays and between antenna elements. Fig.19 The antenna subarray in Fig.17 The antenna subarray in is similar to that in Fig.17 The description of antenna subarray in Fig. 20The antenna subarray in Fig.18 The antenna subarray in is similar to that in Fig.18 The description of the antenna subarray in is not repeated here. The difference is that Fig.19 and Fig. 20 The isolation components include not only the isolation units located between the antenna subarrays (as shown in the figure, the isolation unit A), but also the isolation units located between the antenna elements (as shown in the figure, the isolation unit B). Although the isolation units in the figure are located in different positions, the principle of isolating interference signals at different positions is the same. Please refer to the previous description of different materials used to isolate interference signals, as well as Figures 16 to 18 The description of the isolation unit can be used to understand this and will not be repeated here.

[0182] It should be understood that Figures 17 to 20 This is just a possible distribution of the isolation unit, and should not constitute any limitation to the present application. Due to the particularity of the dual-polarized antenna, it is impossible to set an isolation unit between the two sub-arrays that constitute the dual-polarized antenna. However, in the antenna array composed of other antenna forms, an isolation unit can also be set between every two adjacent antenna sub-arrays. In addition, Fig.17 and Fig.18 The isolation unit between each two antenna subarrays may also be an isolation unit of other forms. For specific examples, see Fig. 22 .

[0183] It should also be understood that Figures 17 to 20 The position of the isolation unit shown is only one possible design. The position of the isolation unit is not limited to being set between two adjacent antenna elements in the horizontal direction or the vertical direction, and can also be set at other positions.

[0184] Fig.21 is another schematic diagram of the isolation unit located between antenna subarrays and between antenna elements. Fig.21 As shown, multiple isolation units are located between each two adjacent antenna subarrays of multiple antenna subarrays. If the two antenna elements that form a cross-polarized antenna are called a group of antenna elements, each isolation unit can be located at the center of the four groups of antenna elements, or in other words, between the two groups of antenna elements on the diagonal line. It is not difficult to understand that setting the isolation unit at the center of the four groups of antenna elements can reduce the interference between different groups of antenna subarrays and between different groups of antenna elements. The isolation effect is similar to Fig. 20 Similar, and the number of isolation units can be saved.

[0185] It should be understood that the above Figures 17 to 21The shapes and positions of the isolation units shown are examples, and those skilled in the art can design isolation units of more shapes based on the same concept, and can also set isolation units at other positions between antenna subarrays and between antenna elements to improve isolation. This application does not limit this.

[0186] Fig. 22 is another schematic diagram of an isolation unit located between antenna subarrays. As an example, Fig. 22 (a), (b), (c), (d) and (e) in FIG. 3 show several different forms of isolation units located between adjacent antennas. Although the forms of the isolation units are different, the principles of isolating interference signals are the same. Please refer to the above description of different materials used to isolate interference signals, as well as Figures 16 to 20 The description of the isolation unit can be used to understand this and will not be repeated here.

[0187] It should be noted that Fig. 22 A possible antenna form is shown, which not only shows the antenna element, but also shows the feeding network and reflector connected to the antenna element.

[0188] It should also be understood that in the same antenna array, such as N antenna subarrays of the present application, the following can be used: Figures 16 to 22 The isolation units shown may be of one or more shapes, or isolation units of other shapes may also be used, and the present application does not limit this.

[0189] The above-mentioned techniques of setting up isolation components between antenna subarrays (or even between antenna elements) and designing different routings for the feed networks of different RF antenna links can be collectively referred to as high-isolation antenna technologies. These high-isolation antenna technologies can eliminate interference signals from different antenna subarrays and improve the isolation between antenna subarrays, that is, improve the isolation between N RF antenna links.

[0190] In addition to the aforementioned solutions 1 to 3, among the N RF antenna links provided in the present application, a self-interference eliminator is connected between the transmit channel and the receive channel of at least one RF antenna link, such as Fig.11 As shown. The self-interference eliminator can be used to eliminate the interference of the signal of the transmission channel in this link to the receiving channel. For the circuit design of the self-interference eliminator, please refer to the previous article combined with Figure 7 For the convenience of explanation, the design scheme of connecting the self-interference eliminator between the transmitting channel and the receiving channel in the same RF antenna link is recorded as scheme 4 in this paper.

[0191] One possible design is that a self-interference eliminator is connected between the transmit channel and the receive channel of each of the N RF antenna links, that is, there are a total of N self-interference eliminators in the AAU. Fig.11 As shown in , a self-interference eliminator is connected between the transmitting channel and the receiving channel of each of the two RF antenna links. Fig.11 The AAU shown in FIG. 1 includes two self-interference cancellers. Fig. 9 Taking the design shown as an example, if N is 2, then a total of 2×2 (ie, 4) self-interference cancellers are included. It can be seen that the number of self-interference cancellers is reduced.

[0192] In other words, in N RF antenna links, if a self-interference eliminator is connected between the transmit channel and the receive channel of each RF antenna link, a total of N (ie, L=N) self-interference eliminators are required. Fig. 9 In the design shown, N×N self-interference cancellers are required. Therefore, in the AAU provided by the present application, the reduction in the number of self-interference cancellers is more significant as N increases.

[0193] Furthermore, the feed network in the AAU includes a phase shifter, each feed network may include one or more phase shifters, and each phase shifter may be connected to one or more antenna elements. Fig.11 As shown, a feeding network includes two phase shifters, each of which is connected to three antenna elements.

[0194] On the one hand, since the phase shifter can be used to adjust the beam direction of the signal, more antenna elements can be used in the antenna subarray to transmit and receive signals. The increase in the number of antenna elements in the antenna array can make the feeding network more free. In other words, the feeding network can have greater freedom to optimize its amplitude and / or phase, thereby providing strong support for optimizing higher isolation.

[0195] On the other hand, each phase shifter can be used to adjust the phase of the signal transmitted or received by the connected antenna element, which causes a phase difference between the downlink signals transmitted by the antenna elements connected to different phase shifters in the same antenna subarray. Therefore, the downlink signals transmitted by different antenna elements can be canceled out by controlling the phase difference, thereby reducing mutual interference.

[0196] It should be understood that, although not shown in the figure, the feeding network may also include other devices, such as attenuators, power dividers, etc., and the present application includes but is not limited to these.

[0197] Fig.23 This is another schematic diagram of the AAU provided in an embodiment of the present application. Fig.23In the AAU shown, every two antenna subarrays form a group to form an array of dual-polarized antennas. An isolation unit can be provided between each group of antenna subarrays and between every two adjacent dual-polarized antennas. Fig.23 The specific location of the isolation unit can be found in the above text. Fig.21 The figure shows three columns of antenna elements, each column is a group (that is, two) of antenna subarrays, so the three groups (or three columns) of antenna subarrays are connected to six RF channels. Each antenna subarray and the RF channel connected to it belong to an RF antenna link. The feeding network in each RF antenna link includes two phase shifters, and each phase shifter is connected to three antenna elements. For the relationship between the phase shifter and the antenna element, please refer to the relevant description above, which will not be repeated.

[0198] For the sake of distinction, the connection between the first antenna subarray and the RF channel from left to right is shown with a solid line in the figure, and the connection between the two antenna subarrays on the right and the RF channels is shown with a dotted line. For the sake of simplicity, only two RF channels are shown in the figure, and the other RF channels can be obtained by referring to the structure shown in the figure.

[0199] In addition, a self-interference canceller can be connected between the transmission channel and the receiving channel of each of the N radio frequency antenna links. The structure of the self-interference canceller can be found in the figure and its related description, and will not be described in detail.

[0200] It should be understood that the above text describes the AAU provided in the embodiment of the present application in combination with multiple accompanying drawings. Based on the same concept, technicians in this field can also make simple changes to expand more possible structures, and these structures should all fall within the scope of protection of the present application.

[0201] In the embodiments of the present application, the design of the feed network and the design of setting isolation components for the antenna subarray can reduce the mutual interference between different antenna subarrays. Applying at least one of these two designs in multiple RF antenna links can reduce the mutual interference between different RF antenna links. In this way, the interference received by the receiving channel in each RF antenna link mainly comes from the downlink signal of the transmitting channel of this link. Therefore, a self-interference canceller can be connected between the transmitting channel and the receiving channel in the RF antenna link to cancel the downlink signal from the transmitting channel in this link, further reducing the interference of the receiving channel. In other words, in the solution provided by the present application, there is no need to connect a self-interference canceller between the transmitting channel and the receiving channel of any two different RF antenna links in the N RF antenna links, which greatly reduces the number of self-interference cancellers, reduces the circuit complexity, and reduces the control complexity accordingly.

[0202] On the other hand, in the receiving channel, since the interference signal has a greater impact on the ADC, it may cause ADC saturation or automatic gain control of the receiving channel, causing a significant deterioration in receiving sensitivity. Therefore, the interference signal can be reduced before the received signal enters the ADC to reduce the impact of the interference signal on the ADC.

[0203] Two solutions for further reducing interference in the receiving channel are provided below, which will be described in detail with reference to the accompanying drawings.

[0204] A possible design to further reduce interference in the receiving channel is that the receiving channel in each RF antenna link includes an LNA, an ADC, and a narrowband filter connected between the ADC and the LNA, and the narrowband filter is used to filter other frequency signals except for the preset frequency. For the convenience of explanation, this article will record the design scheme of connecting a narrowband filter between the LNA and ADC of the receiving channel as Scheme 5.

[0205] Fig.24 is another schematic diagram of the AAU provided in the embodiment of the present application. For ease of understanding and explanation, Fig.24 Specifically, a radio frequency antenna link in the AAU is shown. Fig.24 In the RF antenna link shown, a narrow band filter is connected between the ADC and LNA of the receiving channel. The narrow band filter is a filter with a very narrow passband, which only allows frequencies within a very narrow range to pass through and cuts other frequencies. In the embodiment of the present application, the narrow band filter can pass a certain preset frequency (such as Figure 5 The narrowband filter can filter out the frequency f3) of the signal, while cutting off the signals of other frequencies, which cannot pass through the narrowband filter. Figure 5 In the sub-band duplex working mode shown, the uplink signal is conducted and other signals are filtered out, so that the signal interference entering the ADC is small.

[0206] Since the communication device to which the AAU belongs may need to switch between several different working modes, the above narrowband filter can be used in some working modes, such as the sub-band duplex working mode, and not used in other working modes, such as FDD, TDD and partial full-duplex working modes. Fig.24 Improvements are made on this basis by adding switching elements to control the signal to flow to the ADC through different paths in different working modes.

[0207] Optionally, the receiving channel in each RF antenna link further includes a switch element, and the switch element in each RF antenna link is used to control whether the received signal flows to the ADC through the narrowband filter or not. It should be understood that the design scheme of controlling the signal flow through the switch element can be regarded as an optional scheme provided on the basis of scheme five.

[0208] Fig.25 and Fig.26 These are two other schematic diagrams of the AAU provided in the embodiments of the present application. Fig.25 and Fig.26 exist Fig.10 The existing AAU shown in the figure has a switch element added to it. Fig.10 The same content can be found above Fig.10 The relevant instructions will not be repeated here.

[0209] exist Fig.25 In the embodiment, a switch element is connected in parallel at both ends of the narrowband filter. The switch element may be, for example, a single-pole single-throw switch, which is disconnected in the sub-band duplex working mode so that the signal flows to the ADC through the narrowband filter; and is closed in other working modes so that the signal flows to the ADC through the switch element without passing through the narrowband filter.

[0210] exist Fig.26 In the embodiment, the narrowband filter can also be connected in parallel with the wire and connected between the switch element and the LNA. The switch element can be, for example, a single-pole double-throw switch. In the sub-band duplex working mode, the branch where the narrowband filter is located is turned on, so that the signal flows to the ADC through the narrowband filter; in other working modes, the branch where the wire is located is turned on, and the branch port where the narrowband filter is located is turned on, so that the signal flows to the ADC through the wire without passing through the narrowband filter. In this way, it is possible to switch between the two branches containing the narrowband filter and the branch without the narrowband filter to adapt to different working modes. Fig.26 This is just an example. After being connected in parallel with the wire, the narrowband filter can also be connected between the switch element and the ADC, which can also achieve the effect of switching between the two branches.

[0211] It should be understood that Fig.25 and Fig.26 The switching elements shown and the connection relationship with other devices in the receiving channel are only examples. Those skilled in the art can make equivalent transformations based on the same concept to obtain more possible circuit designs, and these transformations should all fall within the scope of protection of this application.

[0212] Another possible design for further reducing interference in the receiving channel is that at least two of the N antenna subarrays are connected to the ADC on the same receiving channel through phase shifters, and each phase shifter is used to adjust the phase of the uplink signal and the phase of the downlink signal received by the connected antenna subarray. For the convenience of explanation, this article will record the design scheme of connecting multiple antenna subarrays to the ADC of the same receiving channel as scheme six.

[0213] Fig. 27 This is another schematic diagram of the AAU provided in an embodiment of the present application. Fig. 27 exist Fig.10 Based on the existing AAU shown in FIG. 1 , multiple antenna subarrays are connected to the ADC on the same receiving channel through phase shifters. Fig.10 The same content can be found above Fig.10 The relevant instructions will not be repeated here.

[0214] exist Fig. 27 In the example of connecting two antenna subarrays to the ADC of the same receiving channel through phase shifters for easy understanding, the example of connecting two antenna subarrays to the ADC of the same receiving channel through phase shifters is shown. Connecting to the ADC specifically means connecting to the input end of the ADC, that is, the uplink signals and downlink signals received by the two antenna subarrays are phase-adjusted by the phase shifters and then enter the ADC. Fig. 27 This is just an example, and the present application does not limit the number of antenna sub-arrays connected to the ADC on the same receiving channel.

[0215] Connecting multiple antenna subarrays to the same receiving channel can also be understood as merging multiple antenna subarrays with one receiving channel. Through such a design, the phases of multiple antenna subarrays can be adjusted (or optimized) to achieve the enhancement of uplink signals and the weakening of downlink signals in the same receiving channel. And the receiving channel in each RF antenna link of the N RF antenna links can achieve the enhancement of uplink signals and the weakening of downlink signals in the same way.

[0216] It should be understood that the goal of adjusting the phase is: through adjustment, the uplink signals are superimposed in phase and the downlink signals are canceled in opposite directions. The uplink signals are superimposed in phase, that is, the uplink signals from different antenna subarrays are superimposed in phase, and the signal is enhanced. The uplink signals from different antenna subarrays are in phase, which can specifically refer to the uplink signals from different antenna subarrays having a phase difference of an integer multiple of 2π. The downlink signals are canceled in opposite directions, that is, the downlink signals from different antenna subarrays cancel each other in opposite directions, and the energy is weakened. The downlink signals from different antenna subarrays are in opposite phase, which can specifically refer to the downlink signals from different antenna subarrays having a phase difference of an odd multiple of π.

[0217] Among them, the uplink signals from different antenna subarrays have a phase difference of an integer multiple of 2π, and the downlink signals from different antenna subarrays have a phase difference of an odd multiple of π, which is an ideal target for phase adjustment. In practical applications, through continuous adjustment and optimization, the phase difference between the uplink signals from different antenna subarrays can be close to an integer multiple of 2π, and the phase difference between the downlink signals from different antenna subarrays can be close to an odd multiple of π.

[0218] In a possible design, the N antenna subarrays in the AAU can be connected to the ADC on each receiving channel of the N receiving channels through phase shifters, or the N antenna subarrays in the AAU can be connected to the ADC on the same receiving channel through phase shifters, and the ADC on the receiving channel in each of the N RF antenna links in the AAU is connected to the N antenna subarrays. In this way, an N×N fully connected network is formed between the N antenna subarrays and the N receiving channels.

[0219] Through the above design, N antenna subarrays can be combined with one receiving channel, and each of the N receiving channels is respectively combined with the N antenna subarrays. In this way, the N phase shifters connected to the N antenna subarrays can respectively adjust the phase (or optimize) of the signals of the antenna subarrays to which they are connected, so that the N receiving channels can respectively enhance the uplink signal and weaken the downlink signal, thereby helping to improve the receiving performance.

[0220] It should be understood that among the multiple solutions provided above, each solution can be combined with each other to achieve the effect of reducing interference and improving receiving performance.

[0221] For example, one or more of the above schemes 1 to 3 can be used in combination with scheme 4, and on this basis, can be further combined with scheme 5 or scheme 6 to achieve the purpose of secondary interference reduction. Among them, one or more of the above schemes 1 to 3 can be used in combination with scheme 4 to achieve the purpose of first-level interference reduction, and scheme 5 or scheme 6 can achieve the purpose of second-level interference reduction.

[0222] Based on one or more of the above-mentioned schemes 1 to 3 combined with scheme 4, the interference signal can be reduced to below the blocking level (for example, it can be the maximum power allowed by the receiving dynamic range mentioned in the above description of the receiver blocking) before the LNA in the receiving channel, or it can be reduced to a part, but it does not have to be reduced to below the blocking level. Although the degree to which the interference signal is reduced does not meet the requirement of being lower than the blocking level, the reduced interference signal has little effect on the LNA in the receiving channel, such as causing the LNA nonlinear component to be very small, and has little effect on the receiving sensitivity. However, the reduced interference signal has a greater impact on the ADC in the receiving channel, which may cause the ADC to saturate or the automatic gain of the receiving channel to fail to control, causing a significant deterioration in the receiving sensitivity.

[0223] To address the problem of interference signals having a significant impact on the ADC, Scheme 5 or 6 can be further adopted to reduce interference in the receiving channel so that the interference of the received signal is reduced to a lower level before entering the ADC.

[0224] Figures 28 to 30 These are three more schematic diagrams of the AAU provided in the embodiments of the present application. Fig.28 and Fig.29 exist Fig.23 Based on the AAU shown, the Fig.25 and Fig.26 The narrowband filter and switch element shown in the figure are equivalent to combining the above-mentioned schemes 3, 4 and 5. Fig.23 , 25 Or 26, the same content can be found above Fig.23 , 25 The relevant instructions in or 26 are not repeated here.

[0225] Fig.30 exist Fig.23 Based on the AAU shown, Fig.28 The method shown in the figure connects multiple antenna subarrays to the ADC of the same receiving channel through phase shifters, which is equivalent to combining the above-mentioned schemes 3, 4 and 6. Fig.23 Or 28, the same content can be found above Fig.23 or Fig.28 The relevant instructions in will not be repeated here.

[0226] It should be understood that although not shown in the figure, the above-mentioned scheme 1 and scheme 2 can also be further combined with Figures 28 to 30 Any combination scheme in the above can be combined to obtain better interference reduction effect.

[0227] In the embodiments of the present application, the design of the feed network and the design of setting isolation components for the antenna subarray can reduce the mutual interference between different antenna subarrays. Applying at least one of these two designs in multiple RF antenna links can reduce the mutual interference between different RF antenna links. In this way, the interference received by the receiving channel in each RF antenna link mainly comes from the downlink signal of the transmitting channel of this link. Therefore, a self-interference canceller can be connected between the transmitting channel and the receiving channel in the RF antenna link to cancel the downlink signal from the transmitting channel in this link, further reducing the interference of the receiving channel. In other words, in the solution provided by the present application, there is no need to connect a self-interference canceller between the transmitting channel and the receiving channel of any two different RF antenna links in the N RF antenna links, which greatly reduces the number of self-interference cancellers, reduces the circuit complexity, and reduces the control complexity accordingly.

[0228] In addition, by adding a narrowband filter in the receiving channel or connecting multiple antenna subarrays to the ADC in the same receiving channel to adjust the phase, secondary interference reduction in the receiving channel can be achieved, which can further reduce the impact of interference signals on each receiving channel in the AAU and further improve the receiving performance.

[0229] The present application also provides a communication device, which may include an AAU, which may be the above-mentioned Fig.11 , Figures 23 to 30 The AAU shown in any one of the items may also be an AAU that is not shown in the figure but can be obtained based on any one of the aforementioned solutions or a combination of any multiple solutions. Optionally, the communication device also includes a BBU. Optionally, the communication device is a network device. Optionally, the communication device is a terminal device.

[0230] It should be understood that the communication device may also include an AAU and other modules that can be used to implement the same or similar functions as the BBU, and this application is not limited to this.

[0231] By applying the AAU provided in the present application to communication equipment, compared with the traditional base station architecture with a shared transmit and receive antenna, the large-scale use of self-interference cancellers can be reduced, and the problems of high circuit complexity and high control complexity brought about by the N×N fully connected network can be solved; compared with the traditional solution of separating the transmit and receive antennas, the constraints on the size of the base station equipment can be eliminated, and the transmit antenna aperture and the receive antenna aperture are no longer limited by the technical barriers that need to be reduced due to the separation of the transmit antenna and the receive antenna, which is conducive to obtaining a larger uplink and downlink coverage range.

[0232] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. An active antenna unit, characterized in that: include: N radio frequency antenna links and L self-interference cancellers, N is an integer greater than 1, and L is a positive integer less than or equal to N; Each of the N RF antenna links comprises: a transmitting channel, a receiving channel, a feeding network connected to the transmitting channel and the receiving channel, and an antenna subarray connected to the feeding network, wherein the feeding network is used to feed the antenna subarray, and the antenna subarray is used to transmit and receive signals; a self-interference canceller is connected between the transmitting channel and the receiving channel of at least one RF antenna link of the N RF antenna links, and the self-interference canceller is used to cancel the signal from the transmitting channel of the same RF antenna link in the receiving channel of the RF antenna link; The N radio frequency antenna links satisfy at least one of the following: The routing of the feed networks in at least two of the N RF antenna links is different; or The N antenna subarrays in the N radio frequency antenna links are provided with isolation components, and the isolation components are used to isolate signals between the N antenna subarrays.

2. The active antenna unit according to claim 1, characterized in that: Each antenna subarray in the N antenna subarrays includes a plurality of antenna elements, and a feeding network in each radio frequency antenna link in the N radio frequency antenna links includes one or more phase shifters, and each phase shifter is connected to one or more antenna elements.

3. The active antenna unit according to claim 1 or 2, characterized in that: The isolation component includes M decoupling units located above the N antenna subarrays, where M is an integer greater than or equal to N; wherein the decoupling unit located above the first antenna subarray is used to reflect part of the received signal so as to offset the signals from other antenna subarrays in the first receiving channel through the reflected signal, the first antenna subarray is any one of the N antenna subarrays, the first receiving channel is a receiving channel connected to the first antenna subarray, and the other antenna subarrays are one or more antenna subarrays among the N antenna subarrays except the first antenna subarray.

4. The active antenna unit according to claim 1 or 2, characterized in that: The isolation component includes: at least one isolation unit located between adjacent antenna subarrays in the N antenna subarrays, and the at least one isolation unit located between the adjacent antenna subarrays is used to isolate interference signals between at least part of the antenna subarrays in the N antenna subarrays.

5. The active antenna unit according to claim 4, characterized in that: Each of the N antenna subarrays includes multiple antenna elements, and the isolation component also includes: at least one isolation unit located between adjacent antenna elements in each antenna subarray, and the at least one isolation unit located between the adjacent antenna elements is used to isolate interference signals between at least some of the multiple antenna elements.

6. The active antenna unit according to claim 4 or 5, characterized in that: The isolation unit is made of one or more of absorbing materials, scattering materials and metamaterials.

7. The active antenna unit according to any one of claims 1 to 6, characterized in that: The receiving channel in each radio frequency antenna link includes a low noise amplifier LNA, an analog-to-digital converter ADC, and a narrowband filter connected between the ADC and the LNA, and the narrowband filter is used to filter other signals outside a preset frequency.

8. The active antenna unit according to claim 7, characterized in that: The receiving channel in each RF antenna link further includes a switch element, and the switch element is used to control the received signal to flow to the ADC through or not through the narrowband filter.

9. The active antenna unit according to any one of claims 1 to 8, characterized in that: At least two antenna subarrays among the N antenna subarrays are respectively connected to the ADC on the same receiving channel through phase shifters, and the phase shifters are used to adjust the phases of uplink signals and downlink signals received by the connected antenna subarrays.

10. The active antenna unit according to any one of claims 1 to 9, characterized in that: L equals N.

11. A communication device, characterized in that: include: Baseband unit, and An active antenna unit as claimed in any one of claims 1 to 10.

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