CN103873399B - Signal interference processing method, device and trunking - Google Patents
Signal interference processing method, device and trunking Download PDFInfo
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- CN103873399B CN103873399B CN201210531488.1A CN201210531488A CN103873399B CN 103873399 B CN103873399 B CN 103873399B CN 201210531488 A CN201210531488 A CN 201210531488A CN 103873399 B CN103873399 B CN 103873399B
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B7/00—Radio transmission systems, i.e. using radiation field
- H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
- H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
- H04B7/08—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the receiving station
- H04B7/0837—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the receiving station using pre-detection combining
- H04B7/0842—Weighted combining
- H04B7/086—Weighted combining using weights depending on external parameters, e.g. direction of arrival [DOA], predetermined weights or beamforming
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L25/00—Baseband systems
- H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
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Abstract
The embodiment of the present invention provides a kind of signal interference processing method, device and trunking.Signal interference processing unit of the present invention, including:Power distribution module, disturbance reconstruction module and power combing module;Power distribution module, first signal to be sent for obtaining first antenna isolates the secondary signal of the first setting power from the first signal, and secondary signal is inputted to disturbance reconstruction module;Disturbance reconstruction module, interference-cancelled signals are generated for secondary signal, and interference-cancelled signals are inputted to power combing module;Power combing module, the 3rd signal for being received using interference-cancelled signals to the second antenna carry out Interference Cancellation.The interference for the signal that the signal that first antenna is launched receives for the second antenna is avoided, meanwhile, avoid the service efficiency for when by the way of time-division or frequency division, reducing frequency spectrum.
Description
Technical Field
The present invention relates to communications technologies, and in particular, to a method and an apparatus for processing signal interference, and a relay device.
Background
In the current base station system, the base station transmits data to the core network through the network cable, but it is not practical to lay an optical fiber network for the base station system in places where there is no wired resource or it is inconvenient to lay lines, such as the terrains like gobi and mountains, or in time-critical scenes like disaster areas after earthquake, and therefore the problem of the above-mentioned scenes is effectively solved for the wireless backhaul technology (wirelessbackhaul) of the base station system.
In the prior art, in a wireless backhaul technology, User Equipment (User Equipment, abbreviated as UE) sends data to Relay Equipment (Relay), and then the Relay Equipment sends the data to a remote base station, and further sends the data to a core network. Generally, a time division or frequency division manner is adopted to avoid interference generated between data sent by the Relay to the UE and data sent by the remote base station to the Relay.
However, this method using time division or frequency division reduces the efficiency of using the frequency spectrum.
Disclosure of Invention
The embodiment of the invention provides a signal interference processing method, a signal interference processing device and relay equipment, and aims to solve the problem that the spectrum use efficiency is reduced due to the fact that a time division or frequency division method is adopted to avoid self-interference in the prior art.
In one aspect, the present invention provides a signal interference processing apparatus, including: the device comprises a power distribution module, an interference reconstruction module and a power synthesis module;
the power distribution module is configured to acquire a first signal to be transmitted by a first antenna, separate a second signal with a first set power from the first signal, and input the second signal to the interference reconstruction module;
the interference reconstruction module is configured to generate an interference cancellation signal according to the second signal, and input the interference cancellation signal to the power synthesis module;
and the power synthesis module is used for carrying out interference cancellation on a third signal received by the second antenna by adopting the interference cancellation signal.
In a first possible implementation manner of the first aspect of the present invention, the interference reconstruction module includes: the device comprises a power distribution unit, a signal adjusting unit and a power synthesizing unit;
the power distribution unit is configured to separate the second signal into at least two sub-signals with a second set power, and input the at least two sub-signals to the signal adjustment unit;
the signal adjusting unit is used for respectively carrying out amplitude adjustment and/or time delay adjustment on the sub-signals and inputting the adjusted and/or time delay adjusted sub-signals to the power synthesizing unit;
and the power synthesis unit is used for performing power synthesis on the adjusted and/or time-delay-adjusted sub-signals to generate the interference cancellation signal.
With reference to the first possible implementation manner of the first aspect of the present invention, in a second possible implementation manner, the second set powers of the at least two paths of sub signals are the same or different.
With reference to the first aspect, or the first possible implementation manner or the second possible implementation manner of the first aspect, in a third possible implementation manner, the first antenna and the second antenna are disposed on the signal interference processing apparatus; or, the first antenna and the second antenna are base station antennas.
With reference to the third possible implementation manner of the first aspect of the present invention, in a fourth possible implementation manner, if the first antenna and the second antenna are disposed on the signal interference processing apparatus, the apparatus further includes: at least one interface unit;
the interface unit is configured to input a third signal received by the second antenna, and output the third signal to the power combining module.
With reference to the fourth possible implementation manner of the first aspect of the present invention, in a fifth possible implementation manner, the interface unit is further configured to input a fourth signal obtained by separating, by the power distribution module, a second signal with a first set power from the first signal, and output the fourth signal to the first antenna;
the first antenna is further configured to transmit the fourth signal.
With reference to the fourth possible implementation manner or the fifth possible implementation manner of the first aspect of the present invention, in a sixth possible implementation manner, the interface unit includes: the filter is used for carrying out spectrum separation on the uplink signal and the downlink signal transmitted by the first antenna; and/or performing spectrum separation on the uplink signal and the downlink signal transmitted by the second antenna.
With reference to the sixth possible implementation manner of the first aspect of the present invention, in a seventh possible implementation manner, the interface unit further includes: a circulator; the circulator is used for carrying out time separation on the uplink signal and the downlink signal transmitted by the first antenna; and/or performing time separation on the uplink signal and the downlink signal transmitted by the second antenna.
With reference to the foregoing various possible implementation manners of the first aspect, in a ninth possible implementation manner, the method further includes: the radio frequency unit is used for carrying out analog-to-digital conversion on the first signal and inputting the first signal converted into an analog signal to the power distribution module; or,
and the power synthesis module is used for performing analog-to-digital conversion on the third signal and inputting the third signal converted into a digital signal to the power synthesis module.
With reference to the foregoing various possible implementation manners of the first aspect, in a tenth possible implementation manner, the method further includes: and the access digital processing unit is used for performing access processing on the third signal subjected to interference cancellation and transmitting the third signal to the digital processing unit of the base station.
In a second aspect, the present invention provides a relay device, including the signal interference processing apparatus and the digital processing unit as described above;
and the digital processing unit is used for receiving a third signal transmitted by the interference processing device and carrying out data packet filtering processing on the third signal.
In a third aspect, the present invention provides a signal interference processing method, including:
acquiring a first signal to be transmitted by a first antenna;
separating a second signal with first set power from the first signal;
generating an interference cancellation signal according to the second signal;
and carrying out interference cancellation on the third signal received by the second antenna by adopting the interference cancellation signal.
In a first possible implementation manner of the third aspect, the generating an interference cancellation signal according to the second signal includes:
separating the second signal into at least two sub-signals with second set power;
respectively carrying out amplitude adjustment and/or time delay adjustment on the sub-signals;
and performing power synthesis on the adjusted and/or time delay-adjusted sub-signals to generate the interference cancellation signal.
With reference to the first possible implementation manner of the third aspect, in a second possible implementation manner, the second set powers of the at least two paths of sub signals are the same or different.
The signal interference processing method, the signal interference processing device and the relay equipment in the embodiments of the present invention are configured to obtain a first signal to be transmitted by a first antenna through a power distribution module, separate a second signal with a first set power from the first signal, input the second signal to an interference reconstruction module, generate an interference cancellation signal from the second signal through the interference reconstruction module, input the interference cancellation signal to a power synthesis module, and finally perform interference cancellation on a third signal received by a second antenna through the power synthesis module by using the interference cancellation signal. The interference of the signal transmitted by the first antenna to the signal received by the second antenna is avoided, and meanwhile, the signal interference processing device provided by the embodiment does not transmit the signal received by the second antenna and the signal to be transmitted by the first antenna in a time division or frequency division manner, so that the use efficiency of the frequency spectrum is reduced when the time division or frequency division manner is adopted.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.
Fig. 1 is a schematic structural diagram of a signal interference processing apparatus according to a first embodiment of the present invention;
fig. 2 is a schematic structural diagram of a possible interference reconstruction module according to a first embodiment;
fig. 3 is a schematic diagram of a first working principle of an interference reconstruction module according to an embodiment;
fig. 4 is a schematic structural diagram of a second signal interference processing apparatus according to an embodiment of the present invention;
fig. 5 is a schematic diagram of the working principle of the relay device provided with the signal interference processing device according to the present invention;
fig. 6 is a schematic structural diagram of a relay device according to a first embodiment of the present invention;
fig. 7 is a schematic structural diagram of a second relay device according to an embodiment of the present invention;
fig. 8 is a schematic structural diagram of a third relay device according to an embodiment of the present invention;
fig. 9 is a schematic structural diagram of a fourth relay apparatus according to the present invention;
FIG. 10 is a flowchart illustrating a signal interference processing method according to a first embodiment of the present invention
Fig. 11 is a flowchart of a first method for generating an interference cancellation signal according to an embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The techniques described herein may be used in various communication systems, such as current 2G, 3G communication systems and next generation communication systems, such as Global System for Mobile communications (GSM), Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Wideband Code Division Multiple Access (WCDMA), Frequency Division Multiple Access (FDMA), Orthogonal Frequency Division Multiple Access (OFDMA), Long Term-Division Multiple Access (Long Term-Multiple Access), single carrier-FDMA (SC-FDMA), General Packet Radio Service (GPRS), Long Term Evolution (LTE, Long Term Evolution), and other types of communication systems.
Fig. 1 is a schematic structural diagram of a first embodiment of a signal interference processing apparatus according to the present invention, and referring to fig. 1, the signal interference processing apparatus may be disposed on a relay device, for example: relay, or may also be set in a base station as a Relay device, for example: NodeB, eNodeB, etc. The relay device has two groups of antennas, and the signal interference processing device can be used for processing the interference of the transmission signal of one group of antennas to the reception signal of the other group of antennas.
The signal interference processing apparatus includes: the device comprises a power distribution module 10, an interference reconstruction module 11 and a power synthesis module 12.
The power distribution module 10 is configured to obtain a first signal to be transmitted by the first antenna 14, separate a second signal with a first set power from the first signal, and input the second signal to the interference reconstruction module 11.
The function of the power distribution module 10 can be implemented by using a power divider, a directional coupler, and the like. In this embodiment, the first antenna 14 and the second antenna 13 may be antennas provided on the relay device, or may be antennas directly provided on the signal interference processing apparatus. The first signal is a signal to be transmitted by the first antenna 14, and the third signal is a signal received by the second antenna 13.
Specifically, the first signal to be transmitted by the first antenna 14 may be an uplink signal or a downlink signal. If the first signal is an uplink signal, the first signal may be a signal that is sent to the relay device by the UE and then sent to the remote base station by the first antenna of the relay device; if the first signal is a downlink signal, the first signal may be a signal that is sent to the relay device by the remote base station and then sent to the UE by the relay device. The power distribution module 10 may perform power distribution on the first signal, and separate the second signal from the first signal, where a specific power value of the first set power may be set according to an actual requirement or an empirical value, which is not limited herein, and it is understood that a signal obtained after the second signal is separated from the first signal needs to meet a normal requirement of being sent to the UE or the remote base station.
And an interference reconstruction module 11, configured to generate an interference cancellation signal according to the second signal, and input the interference cancellation signal to the power synthesis module 12.
Specifically, after the interference reconstruction module 11 receives the second signal input by the power distribution module 10, the interference reconstruction module 11 may process the second signal by adjusting the amplitude and/or adjusting the phase, so as to generate an interference cancellation signal. It should be noted that, because the signal transmitted by the first antenna 14 can generate interference on the signal received by the second antenna 13, and the signal received by the second antenna 13 is usually mixed with the signal transmitted by the first antenna 14, in this embodiment of the present invention, the second signal with a certain power is separated from the first signal to be transmitted by the first antenna 14 to perform interference cancellation on the third signal received by the second antenna 13. The interference reconstruction module 11 may make the amplitude and/or phase of the obtained interference signal closer to the signal interfering with the third signal received by the second antenna 13 by performing amplitude and/or phase adjustment processing on the second signal. It is to be understood that the amplitude adjustment and/or the phase adjustment performed by the interference reconstruction module 11 may be performed based on empirical values.
And a power combining module 12, configured to perform interference cancellation on the third signal received by the second antenna 13 by using the interference cancellation signal.
The function of the power combining module 12 can be implemented by using a combiner, a power divider, a coupler, and the like. Specifically, the power combining module 12 performs power combining on the interference cancellation signal and the third signal received by the second antenna 13, and cancels the interference signal in the third signal through the interference cancellation signal, so that the combined signal is closer to the signal received by the second antenna 13 in an ideal state because the interference is cancelled.
It should be noted that the third signal received by the second antenna 13 may be an uplink signal or a downlink signal. If the third signal is an uplink signal, the third signal may be a signal sent by the UE and received by the second antenna 13 of the relay device, and the relay device may also send a signal obtained by performing interference cancellation on the third signal to the remote device; if the third signal is a downlink signal, the third signal may be a signal received by the second antenna 13 of the relay device and sent by the remote device, and the relay device may also send a signal obtained by cancelling the third signal with interference to the UE.
Optionally, in order to facilitate using the signal interference processing apparatus according to the embodiment of the present invention, the first antenna and the second antenna according to the embodiment of the present invention may be directly disposed on the signal interference processing apparatus, so that the function of transmitting and receiving signals is directly implemented by the first antenna and the second antenna without any improvement on the existing relay device.
Or, the first antenna and the second antenna may be antennas on relay equipment such as a base station, so that the signal interference processing apparatus may utilize antennas on existing relay equipment, which may save cost.
In the signal interference processing apparatus provided in this embodiment, a power distribution module is used to separate a second signal with a certain power from a first signal to be transmitted by a first antenna, an interference reconstruction module is used to generate an interference cancellation signal according to the second signal, and an interference cancellation signal is used in a power synthesis module to perform interference cancellation on a third signal received by a second antenna. Therefore, the interference of the signal transmitted by the first antenna to the signal received by the second antenna is reduced, and the use efficiency of the frequency spectrum is improved.
Based on the embodiment shown in fig. 1, fig. 2 is a schematic structural diagram of a first possible embodiment of an interference reconstruction module, and referring to fig. 2, the interference reconstruction module 11 includes: power distribution section 110, signal adjustment section 111, and power combining section 112.
The power dividing unit 110 is configured to divide the second signal into at least two sub-signals with a second set power, and input the at least two sub-signals to the signal adjusting unit 111.
Based on the embodiment shown in fig. 2, fig. 3 is a schematic diagram of an operating principle of a first embodiment of the interference reconstruction module, and referring to fig. 2 and 3, the power distribution unit 110 may separate the second signal into at least two sub-signals with second set power, where the power of the at least two sub-signals may be equal or unequal, which is not limited herein.
The signal adjusting unit 111 is configured to perform amplitude adjustment and/or delay adjustment on the sub-signals, and input the adjusted and/or delay-adjusted sub-signals to the power combining unit 112.
Specifically, referring to fig. 3, the signal adjusting unit 111 may perform amplitude adjustment and/or delay adjustment on each path of sub-signal, where the sub-signal after the amplitude adjustment and/or delay adjustment may eliminate a self-interference signal of the signal interference processing apparatus, and may also eliminate multipath self-interference caused by environmental reflection in a third signal received by the second antenna. It should be noted that the amplitude and the adjustment amplitude of the time delay adjusted by the signal adjusting unit 111 may be fixed, or may be changed according to actual requirements. Specifically, the amplitude adjustment and/or the delay adjustment are controlled by a specific algorithm, which is not limited in the present invention.
And a power synthesis unit 112, configured to perform power synthesis on the amplitude-adjusted and/or delay-adjusted sub-signals, so as to generate an interference cancellation signal. The power combining unit 112 transmits the generated interference cancellation signal to the power combining module 12 in fig. 1.
Optionally, in an implementation scenario in which the first antenna and the second antenna are disposed on the signal interference processing apparatus, the signal interference processing apparatus may further include: at least one interface unit.
And the interface unit is used for inputting the third signal received by the second antenna and outputting the third signal to the power synthesis module. That is, the interface unit serves as an interface between the second antenna and the power combining module in the signal interference processing apparatus.
The interface unit is further configured to input a fourth signal obtained by separating the second signal with the first set power from the first signal by the power distribution module, and output the fourth signal to the first antenna, where the first antenna is further configured to transmit the fourth signal. That is, the interface unit may also serve as an interface between the first antenna and the power distribution module in the signal interference processing apparatus.
Specifically, the first antenna and the second antenna may share one interface unit or may be connected to one interface unit, fig. 4 is a schematic structural diagram of a second embodiment of the signal interference processing apparatus according to the present invention, and as shown in fig. 4, the signal interference processing apparatus provided in this embodiment includes 2 interface units, the first antenna 14 is connected to the first interface unit 16, and the second antenna 13 is connected to the second interface unit 15. In the signal interference processing apparatus shown in fig. 4, a solid black line with an arrow indicates a transmission process of a signal, which may be an uplink signal or a downlink signal, but with the signal interference processing apparatus 11 provided in this embodiment, the uplink signal and the downlink signal may be received at the same time, that is, the second antenna 13 receives the downlink signal and also transmits the uplink signal, and the corresponding first antenna 14 also receives the uplink signal while transmitting the downlink signal. Of course, if the second antenna 13 receives an uplink signal and transmits a downlink signal, the first antenna 14 performs corresponding adjustment. The present embodiment is not limited to specific signals transmitted or received by the first antenna 14 and the second antenna 13. In order to ensure that the uplink signal and the downlink signal are transmitted simultaneously, the present embodiment introduces an interface unit, which is used for performing duplex transmission on the uplink signal and the downlink signal.
Optionally, when the signal interference processing apparatus is disposed on a base station in a Frequency Division Duplex (FDD) mode as a relay device, an access digital processing unit of the signal interference processing apparatus may be connected to a digital processing unit of the base station through a network cable, the digital processing unit of the base station is mainly configured to filter an uplink signal or a downlink signal, and the signal interference processing apparatus may receive the filtered uplink signal or downlink signal input by the digital processing unit. The interface unit may include: and the filter is used for performing spectrum separation on the uplink signal and the downlink signal transmitted by the first antenna and/or performing spectrum separation on the uplink signal and the downlink signal transmitted by the second antenna.
When the signal interference processing apparatus is disposed on a base station in a Time Division Duplex (TDD) mode as a relay device, an access digital processing unit of the signal interference processing apparatus may be connected to a digital processing unit of the base station through a network cable, and in this case, the interface unit may further include: a circulator. The circulator is used for carrying out time separation on the uplink signal and the downlink signal transmitted by the first antenna. And/or performing time separation on the uplink signal and the downlink signal transmitted by the second antenna.
Optionally, the signal interference processing apparatus may further include an access digital processing unit, configured to perform access processing on the third signal with interference cancellation, and transmit the third signal to the digital processing unit of the base station.
Specifically, the access digital processing unit arranged in the signal interference processing device can be connected with the digital processing unit in the base station as the relay equipment through a network cable, so that in the process of arranging the signal interference processing device on the base station as the relay equipment, relevant modules and circuits in the base station do not need to be modified and upgraded, and the installation process is simplified. Also, in the case where the access digital processing unit is integrally provided with the existing base station as the relay device, since the existing base station integrates the function of the access digital processing unit, the signal interference processing apparatus may not include the access digital processing unit.
The invention also provides an embodiment of a Relay device, which can be a Relay, NodeB, eNodeB, or other type device, and is provided with the signal interference processing apparatus provided by the embodiment of the invention. The present embodiment is described taking a base station as an example of a relay device. Fig. 5 is a schematic diagram of the working principle of the relay device provided with the signal interference processing device according to the present invention, and referring to fig. 5, the relay device is composed of the existing base station and the signal interference processing device, so that the communication between the core network connected to the remote base station and the UE is ensured, and the signal interference processing device is conveniently connected to the digital processing unit of the existing base station, and the signal interference processing device can generate an interference cancellation signal according to the transmission signal of one group of antennas, and simultaneously combine the interference cancellation signal with the reception signal of the other group of antennas, so as to eliminate the interference of the transmission signal on the reception signal, thereby reducing the interference of the transmission signal of the first antenna on the reception signal of the second antenna, and improving the use efficiency of the frequency spectrum.
The digital processing unit in the base station as the relay device is used for receiving the third signal transmitted by the interference processing device and filtering the third signal.
Specifically, the third signal may also have a residual interference signal, and the residual interference signal is filtered by a digital processing unit in the base station as the relay device.
The relay devices provided by the present invention have slightly different internal structures in different implementation scenarios, and the following embodiments respectively describe the relay devices in different scenarios.
Fig. 6 is a schematic structural diagram of a first embodiment of the relay device in the present invention, and it should be noted that, as shown in fig. 6, a solid black line with an arrow indicates an uplink signal, a dashed black line with an arrow indicates a downlink signal, and the uplink signal and the downlink signal may be divided into multiple uplink signals and multiple downlink signals in the signal interference processing apparatus, and each of the uplink signals and the downlink signals in fig. 6 is illustrated as being divided into two paths. The signal interference processing device of the relay device is provided with a first antenna and a second antenna, and the first antenna and the second antenna may respectively comprise one or more antennas. In this embodiment, the base station serving as the relay device transmits signals in the FDD mode. The access digital processing unit 18 of the signal interference processing device is connected with the digital processing unit 19 of the base station through a network cable.
The signal interference processing device can receive the downlink signal sent to the UE by the remote base station and send the downlink signal to the UE; the uplink signal sent by the UE to the remote base station may also be received, and the uplink signal is sent to the remote base station, so the first antenna shown in fig. 6 may receive the downlink signal sent by the remote base station, and may also send the uplink signal to the remote base station. The second antenna may receive an uplink signal transmitted by the UE, or may transmit a downlink signal to the UE.
Since the signal interference processing apparatus in this embodiment is connected to an existing base station for FDD mode transmission as a relay device, the interface unit may include a first filter 16 and a second filter 15 in order to perform duplex transmission of an uplink signal and a downlink signal.
The first filter 16 is configured to perform frequency division transmission on the uplink signal received by the first antenna and the downlink signal to be sent.
And a second filter 15, configured to perform frequency division transmission on the downlink signal received by the second antenna and the uplink signal to be sent.
In the signal interference processing apparatus of this embodiment, two sets of radio frequency units are provided, and since the signal interference processing apparatus can process the uplink signal and the downlink signal simultaneously, one set of radio frequency units includes: a first transmitting signal processing module 171 and a first receiving signal processing module 172, and another set of radio frequency units includes: a second transmit signal processing module 173 and a second receive signal processing module 174. Of course, the first antenna and the second antenna may share a set of rf units.
Taking the first group of radio frequency units as an example, the first transmit signal processing module 171 is configured to convert the downlink signal to be transmitted, received from the digital processing unit 19 in the existing base station, from a digital signal to an analog signal, and transmit the analog signal to the third power distribution module 103 and the fourth power distribution module 104.
The first received signal processing module 172 converts the uplink signal received by the first antenna from an analog signal to a digital signal, and transmits the digital signal to the digital processing unit 19 for access processing. Specifically, the uplink signal received by the first antenna is synthesized by the first power synthesis module 121 and the second power synthesis module 122, and then input to the first received signal processing module 172.
Take the second group of rf units as an example. The second transmit signal processing module 173 is configured to convert the uplink signal to be transmitted, received from the access digital processing unit 18, from a digital signal to an analog signal, and transmit the analog signal to the first power distribution module 101 and the second power distribution module 102.
The second received signal processing module 174 converts the downlink signal received by the second antenna from an analog signal to a digital signal, and transmits the digital signal to the access digital processing unit 18 for access processing. Specifically, the downlink signal received by the second antenna is synthesized by the third power synthesis module 123 and the fourth power synthesis module 124, and then input to the second received signal processing module 172.
The operation principle of the relay device according to the present embodiment will be described with reference to fig. 6.
First, the relay device will be described by taking an example of processing a downlink signal.
The second antenna receives a downlink signal (i.e., a third signal) transmitted by the remote base station, where the signal is an analog signal. The second antenna transmits the downlink signal to the second filter 15, and since the second antenna also transmits the uplink signal at the same time, the second filter 15 performs frequency division transmission processing on the downlink signal and the uplink signal to be transmitted, and transmits the downlink signal to the third power combining module 123 and the fourth power combining module 124. The third power combining module 123 and the fourth power combining module 124 correspond to a downlink signal received by the second antenna, respectively.
Referring to fig. 6, the third power distribution module 103 and the fourth power distribution module 104 obtain a downlink signal (i.e., a first signal) to be sent by the first antenna, separate a path of second signal with a first set power from the downlink signal, and send the second signal to the interference reconstruction module 11, where the interference reconstruction module 11 generates an interference cancellation signal according to the second signal, and optionally, the interference reconstruction module 11 may obtain the interference cancellation signal by using the technical scheme shown in fig. 3. The interference reconstruction module 11 inputs the interference cancellation signal to the third power synthesis module 123 and the fourth power synthesis module 124, respectively, and performs power synthesis with the downlink signal sent by the remote base station received by the second antenna, so as to cancel the interference of the signal transmitted by the first antenna to the signal received by the second antenna.
The downlink signal after being combined and processed by the interference cancellation signal through the third power combining module 123 and the fourth power combining module 124 passes through the second received signal processing module 174, the access digital processing unit 18, the digital processing unit 19 of the existing base station, the first transmitted signal processing module 171, the power distribution module (i.e., the third power distribution module 103 and the fourth power distribution module 104), the first filter 16, and is finally transmitted to the UE through the first antenna.
Specifically, when the downlink signal passes through the second received signal processing module 174, the second received signal processing module 174 converts the downlink signal from an analog signal to a digital signal, and inputs the digital signal to the access digital processing unit 18, and the access digital processing unit 18 performs access processing on the downlink signal. The access digital processing unit 18 inputs the downlink signal after the access processing to the digital processing unit 19 of the base station through the network cable, and the digital processing unit 19 of the base station performs corresponding filtering processing on the downlink signal. The digital processing unit 19 of The base station transmits The filtered downlink signal to a transmission signal processing module in another group of radio frequency units through a Common Public radio interface (CRPI), that is, The first transmission signal processing module 171 in fig. 6, The first transmission signal processing module 171 converts The downlink signal from a digital signal into an analog signal, and when The downlink signal is converted from a digital signal into an analog signal by The first transmission signal processing module 171 and transmitted to The third power distribution module 103 and The fourth power distribution module 104, The third power distribution module 103 and The fourth power distribution module 104 perform power distribution on The downlink signal again, separate a signal (that is, a second signal) with a first set power and transmit The signal to The interference reconstruction module 11, so as to generate an interference cancellation signal and transmit The signal to The power synthesis modules, that is, The third power synthesis module 123 and The fourth power synthesis module 124 in fig. 6, so that the power synthesis module synthesizes the interference cancellation signal with the downlink signal received by the second antenna to cancel the signal interference. Meanwhile, the downlink signal (i.e., the fourth signal) obtained by separating the third power distribution module 103 and the fourth power distribution module 104 is transmitted to the first filter 16, and is sent to the UE through the first antenna.
It should be noted that, in the initialization stage of the relay device, when the second antenna device receives a downlink signal, at this time, because the first antenna device does not have a downlink signal to be sent, and the third power distribution module 103 and the fourth power distribution module 104 do not obtain the downlink signal to be sent, no interference cancellation signal is generated in the power synthesis module 11, the power synthesis processing is not performed when the downlink signal passes through the third power synthesis module 123 and the fourth power synthesis module 124, and after the signal with the first set power (i.e., the second signal) is separated when the downlink signal passes through the third power distribution module 103 and the fourth power distribution module 104, the power synthesis module 11 can generate the interference cancellation signal according to the second signal.
The technical solution of the present embodiment for processing the uplink signal with the black solid line is similar to the technical solution of the present embodiment for processing the downlink signal, and the difference is that the uplink signal sent by the UE to the remote base station is received by the first antenna and finally sent by the second antenna. In this embodiment, the first antenna is used for receiving uplink signals and transmitting downlink signals, and the second antenna is used for receiving downlink signals and transmitting uplink signals. The function of the first antenna and the function of the second antenna are replaced with each other, which does not affect the technical solution provided by the present invention, and therefore, the present invention is not limited.
Fig. 7 is a schematic structural diagram of a second embodiment of the relay device in the present invention, and the technical solution and the working principle thereof are similar to those of the second embodiment of the relay device in the present invention, and are not described herein again. It should be noted that, as shown in fig. 7, when the interference processing apparatus in this embodiment is connected to the digital processing module of the base station in TDD mode transmission as a relay device, two circulators, i.e., a first circulator 20 and a second circulator 21, need to be added on the basis of fig. 6.
The first circulator 20 and the second circulator 21 are configured to perform time division transmission processing on the uplink signal and the downlink signal.
Specifically, the first circulator 20 and the second circulator 21 are configured to separate the uplink signal and the downlink signal into different radio frequency channels for corresponding processing. Referring to fig. 7, taking the second circulator 21 as an example, the second circulator 21 separates the uplink signal and the downlink signal into a second transmit signal processing module 173 and a second receive signal processing module 174, respectively, for corresponding processing.
Fig. 8 is a schematic structural diagram of a third embodiment of the relay device in the present invention, and a technical scheme and a working principle thereof are similar to those of the third embodiment of the relay device in the present invention, and are not described herein again. It should be noted that, when the interference processing apparatus in this embodiment is connected to the digital processing module 19 of the base station for FDD mode transmission as a relay device, the digital processing unit 19 on the base station is integrated with a group of radio frequency units, and the digital processing unit 19 has a function of performing interconversion between an analog signal and a digital signal on the signal. In this case, a group of rf units needs to be replaced by a third filter 22 connected to the digital processing unit 19 of the base station on the basis of fig. 6.
The third filter 22 is connected to the data processing unit 19 through a network cable, the third filter 22 transmits the uplink signal sent to the data processing unit, i.e. the uplink signal is indicated by a black arrow line in fig. 8, to the digital processing unit 19, and transmits the downlink signal transmitted to the third filter 22 by the digital processing unit 19 to the third power distribution module 103 and the fourth power distribution module 104.
Fig. 9 is a schematic structural diagram of a fourth relay device in the present invention, and a technical scheme and a working principle thereof are similar to those of the fourth relay device in the present invention, and are not described herein again. It should be noted that, when the interference processing apparatus in this embodiment is connected to the digital processing module 19 of the existing base station for FDD mode transmission as a relay device, the digital processing unit 19 on the base station is integrated with the radio frequency unit, and the access digital processing unit 18 is integrated with the radio frequency unit. The access digital processing unit 18 has a function of converting the signals between analog signals and digital signals. Now it is necessary to replace the fourth filter 23 with a group of radio frequency units connected to the access digital processing unit 18 on the basis of fig. 8.
Since the circuit of the rf unit cannot be modified when the signal interference processing apparatus is installed in an existing base station in a case where the access data processing unit 18 is integrated with the rf unit, specifically, the second transmit signal processing module 173 and the second receive signal processing module 174, a fourth filter 23 is provided to be connected to the access data processing unit 18 through a network cable, and is configured to receive the uplink signal transmitted by the access digital processing unit 18 and transmit the uplink signal to the first power distribution module 101 and the second power distribution module 102. Or is configured to receive the downlink signals transmitted by the third power combining module 123 and the fourth power combining module 124, and transmit the downlink signals to the access digital processing unit 18.
Fig. 10 is a flowchart of a first embodiment of a signal interference processing method according to the present invention, as shown in fig. 10, including the following steps:
step 100, a first signal to be transmitted of a first antenna is obtained.
Specifically, a power allocation module in the signal interference processing apparatus acquires a first signal to be transmitted by a first antenna. The first signal may be an uplink signal or a downlink signal.
Step 101, a second signal with a first set power is separated from the first signal.
Specifically, the power distribution module in the signal interference processing apparatus separates a second signal with a first set power from the first signal. The specific power value of the first set power may be set according to an actual requirement or an empirical value, which is not limited herein, and it can be understood that a signal obtained by separating the second signal from the first signal needs to ensure that a normal requirement of communication is satisfied.
And 102, generating an interference cancellation signal according to the second signal.
Specifically, an interference reconstruction module in the signal interference processing apparatus generates an interference cancellation signal according to the second signal.
And 103, carrying out interference cancellation on the third signal received by the second antenna by adopting the interference cancellation signal.
Specifically, a power combining module in the signal interference processing apparatus performs power combining on the interference cancellation signal and the third signal received by the second antenna, so as to cancel interference of the first signal to be transmitted by the first antenna on the third signal received by the second antenna. And the third signal may also be an upstream signal or a downstream signal.
It should be noted that the first signal to be sent by the first antenna may be an uplink signal or a downlink signal, that is, the first antenna may be an interface antenna corresponding to the remote base station or an interface antenna corresponding to the UE, and similarly, the corresponding second antenna may be an interface antenna corresponding to the UE or an interface antenna corresponding to the remote base station. And, for the method provided by the invention, the uplink signal and the downlink signal can be processed simultaneously. Taking the first antenna as the interface antenna corresponding to the remote base station as an example, the first antenna may receive the downlink signal sent by the remote base station and simultaneously send the uplink signal to the remote base station. Correspondingly, the second antenna may receive an uplink signal sent by the UE, and send a downlink signal to the UE at the same time.
The method provided in this embodiment adopts the technical solution provided in fig. 1, and achieves similar technical effects, which are not described herein again.
Further, fig. 11 is a flowchart of a first embodiment of the method for generating an interference cancellation signal according to the present invention, and as shown in fig. 11, for step 102, the interference cancellation signal may be generated by the following steps:
and 102a, separating the second signal into at least two sub-signals with second set power.
Specifically, the power distribution unit in the interference reconstruction module separates the second signal into at least two sub-signals with second set power. The second setting powers of the at least two paths of sub-signals are the same or different, and are not limited herein.
And 102b, respectively carrying out amplitude adjustment and/or time delay adjustment on the sub-signals.
And a signal adjusting unit in the interference reconstruction module respectively adjusts the amplitude and/or the time delay of the sub-signals. The signal adjusting unit may perform amplitude adjustment and/or delay adjustment on each path of sub-signals, and the sub-signals after amplitude adjustment and/or delay adjustment may eliminate a self-interference signal of the signal interference processing apparatus, and may also eliminate multipath self-interference caused by environmental reflection in a third signal received by the second antenna. It should be noted that the amplitude value adjusted by the signal adjusting unit and the adjustment amplitude of the time delay may be fixed, or may be changed according to actual requirements.
And 102c, performing power synthesis on the amplitude-adjusted and/or time-delay-adjusted sub-signals to generate interference cancellation signals.
Specifically, a power synthesis unit in the interference reconstruction module performs power synthesis on the amplitude-adjusted and/or delay-adjusted sub-signals to generate an interference cancellation signal. Optionally, referring to the technical scheme shown in fig. 3, an interference cancellation signal is generated.
The method for generating an interference cancellation signal provided in this embodiment adopts the technical scheme provided in fig. 3, so that similar technical effects are achieved, and details are not described here.
Those of ordinary skill in the art will understand that: all or a portion of the steps of implementing the above-described method embodiments may be performed by hardware associated with program instructions. The program may be stored in a computer-readable storage medium. When executed, the program performs steps comprising the method embodiments described above; and the aforementioned storage medium includes: various media that can store program codes, such as ROM, RAM, magnetic or optical disks.
Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.
Claims (7)
1. A signal interference processing apparatus, comprising: the device comprises a power distribution module, an interference reconstruction module and a power synthesis module;
the power distribution module is configured to acquire a first signal to be transmitted by a first antenna, separate a second signal with a first set power from the first signal, and input the second signal to the interference reconstruction module;
the interference reconstruction module is configured to generate an interference cancellation signal according to the second signal, and input the interference cancellation signal to the power synthesis module;
the power synthesis module is configured to perform interference cancellation on a third signal received by the second antenna by using the interference cancellation signal;
the interference reconstruction module comprises: the device comprises a power distribution unit, a signal adjusting unit and a power synthesizing unit;
the power distribution unit is configured to separate the second signal into at least two sub-signals with a second set power, and input the at least two sub-signals to the signal adjustment unit;
the signal adjusting unit is used for respectively carrying out amplitude adjustment and/or time delay adjustment on the sub-signals and inputting the adjusted and/or time delay adjusted sub-signals to the power synthesizing unit;
the power synthesis unit is used for performing power synthesis on the amplitude-adjusted and/or time-delay-adjusted sub-signals to generate the interference cancellation signal;
the first antenna and the second antenna are arranged on the signal interference processing device; or, the first antenna and the second antenna are base station antennas;
the first antenna and the second antenna are disposed on the signal interference processing apparatus, and the apparatus further includes: at least one interface unit;
the interface unit is configured to input a third signal received by the second antenna, and output the third signal to the power combining module;
the interface unit is further configured to input a fourth signal obtained by separating a second signal with a first set power from the first signal by the power distribution module, and output the fourth signal to the first antenna;
the first antenna is further configured to transmit the fourth signal.
2. The apparatus of claim 1, wherein the second setting powers of the at least two sub-signals are the same or different.
3. The apparatus of claim 1, wherein the interface unit comprises: the filter is used for carrying out spectrum separation on the uplink signal and the downlink signal transmitted by the first antenna; and/or performing spectrum separation on the uplink signal and the downlink signal transmitted by the second antenna.
4. The apparatus of claim 3, wherein the interface unit further comprises: a circulator; the circulator is used for carrying out time separation on the uplink signal and the downlink signal transmitted by the first antenna; and/or performing time separation on the uplink signal and the downlink signal transmitted by the second antenna.
5. The apparatus of claim 1, further comprising: the radio frequency unit is used for carrying out analog-to-digital conversion on the first signal and inputting the first signal converted into an analog signal to the power distribution module; or,
and the power synthesis module is used for performing analog-to-digital conversion on the third signal and inputting the third signal converted into a digital signal to the power synthesis module.
6. The apparatus of claim 1, further comprising: and the access digital processing unit is used for performing access processing on the third signal subjected to interference cancellation and transmitting the third signal to the digital processing unit of the base station.
7. A relay device, characterized by comprising the signal interference processing apparatus according to any one of claims 1 to 6 and a digital processing unit;
and the digital processing unit is used for receiving a third signal transmitted by the interference processing device and filtering the third signal.
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CN106664104A (en) * | 2014-07-15 | 2017-05-10 | 华为技术有限公司 | Signal recover method and signal transceiver device |
US9667292B2 (en) * | 2015-06-26 | 2017-05-30 | Intel Corporation | Method of processing signals, data processing system, and transceiver device |
US10230423B2 (en) * | 2015-11-10 | 2019-03-12 | Huawei Technologies Canada Co., Ltd. | System and method for balanced passive cancellation for full duplex communications |
EP3410605A1 (en) | 2017-06-02 | 2018-12-05 | Intel IP Corporation | Communication device and method for radio communication |
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CN110474656B (en) * | 2019-06-27 | 2022-02-22 | 维沃移动通信有限公司 | Signal transmitting and receiving device and electronic equipment |
CN117294411A (en) * | 2022-06-20 | 2023-12-26 | 中兴通讯股份有限公司 | Signal processing method, signal processing system, signal processing device, and storage medium |
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