A phase synchronization system between multiple base station devices

Abstract

The present invention discloses a phase synchronization system between multiple base station devices, comprising: a baseband processing unit; a first active antenna unit comprising: a first power divider, a first amplifier, a first external interface and a second amplifier; a second active antenna unit comprising: a second external interface and a third amplifier; the first external interface is connected to the second external interface; the baseband processing unit is used to send a first signal to the first active antenna unit; the first active antenna unit is used to convert the first signal into a first local oscillator signal, and transmit the first local oscillator signal to the first power divider, so that the first power divider divides the first local oscillator signal into a second local oscillator signal and a third local oscillator signal; wherein the second local oscillator signal is transmitted to an internal frequency mixing device of the first active antenna unit; the third local oscillator signal is transmitted to the second external interface; the second active antenna unit is used to transmit the third local oscillator signal to the internal frequency mixing device of the second active antenna unit.

Description

Technical Field

[0001] The present invention relates to the field of communication technology, and in particular to a phase synchronization system between multiple base station devices. Background Art

[0002] With the evolution of communication perception technology, the perception distance is very important for base station equipment. The existing multi-base station designs with perception capabilities are mainly dual-station perception design and multi-station collaborative perception design. Taking the dual-station perception design as an example, it is assumed that there are two AAUs (Active Antena Units), namely the first active antenna unit and the second active antenna unit; the dual-station collaborative perception solution uses the first active antenna unit and the second active antenna unit for joint transmission and reception. In theory, the receiving gain can be improved through joint transmission and reception, thereby improving the transmission capability or receiving capability of the entire system. However, this type of networking will cause phase jitter when the first active antenna unit and the second active antenna unit have different internal clock reference sources, that is, due to the differences in the crystal oscillator devices (such as digital baseband processing units and phase-locked loops) inside the first active antenna unit and the second active antenna unit, thereby deteriorating the phase noise performance and limiting the perception distance between the first active antenna unit and the second active antenna unit. Summary of the invention

[0003] The embodiment of the present invention provides a phase synchronization system between multiple base station devices, which can effectively solve the problem of phase jitter and phase asynchronism caused by different internal clock reference sources when the first active antenna unit and the second active antenna unit are jointly sensed in the prior art. The first active antenna unit and the second active antenna unit both use the local oscillator signal processed by the first active antenna unit to achieve the same signal source, that is, the phase synchronization between the two active antenna units is achieved, and the sensing distance of the two active antenna units is improved.

[0004] An embodiment of the present invention provides a phase synchronization system between multiple base station devices, comprising: a first active antenna unit, a second active antenna unit and a baseband processing unit;

[0005] The first active antenna unit comprises: a first power distributor, a first amplifier, a first external interface and a second amplifier;

[0006] The second active antenna unit includes: a second external interface and a third amplifier;

[0007] The first external interface is connected to the second external interface;

[0008] The baseband processing unit is used to send a first signal to the first active antenna unit when the first active antenna unit is used as a signal input source;

[0009] The first active antenna unit is used to convert the first signal into a first local oscillator signal, and transmit the first local oscillator signal to a first power divider, so that the first power divider divides the first local oscillator signal into a second local oscillator signal and a third local oscillator signal; wherein the second local oscillator signal is transmitted to an internal frequency mixing device of the first active antenna unit; and the third local oscillator signal is transmitted to a second external interface of the second active antenna unit via the first amplifier and the first external interface;

[0010] The second active antenna unit is used to transmit the third local oscillator signal to the internal mixing device of the second active antenna unit via the third amplifier.

[0011] Further, the first active antenna unit further includes: a first switch and a second switch;

[0012] The second local oscillator signal is transmitted to the internal frequency mixing device of the first active antenna unit; the third local oscillator signal is transmitted to the second external interface of the second active antenna unit via the first amplifier and the first external interface, including:

[0013] The second local oscillator signal is transmitted to the internal frequency mixing device of the first active antenna unit via the second switch;

[0014] The third local oscillator signal is transmitted to the second external interface of the second active antenna unit via the first amplifier, the first switch and the first external interface.

[0015] Furthermore, the second active antenna unit further includes: a third switch and a fourth switch;

[0016] The method of transmitting the third local oscillator signal to the internal frequency mixing device of the second active antenna unit via the third amplifier includes:

[0017] The third local oscillator signal is transmitted to the internal frequency mixing device of the second active antenna unit via the third switch, the third amplifier and the fourth switch.

[0018] Furthermore, the first active antenna unit further includes: a signal conversion unit;

[0019] The signal conversion unit includes: a digital baseband processing unit, a digital phase-locked loop, an analog phase-locked loop and a radio frequency phase-locked loop connected in sequence;

[0020] The method for converting the first signal into a first local oscillator signal includes:

[0021] Transmitting the first signal to the digital baseband processing unit, so that the digital baseband processing unit converts the first signal into a reference clock signal to be recovered, and transmits the reference clock signal to be recovered to a digital phase-locked loop;

[0022] The digital phase-locked loop converts the reference clock signal to be recovered into a first reference clock signal, and transmits the first reference clock signal to the analog phase-locked loop;

[0023] The analog phase-locked loop converts the first reference clock signal into a second reference clock signal, and transmits the second reference clock signal to a radio frequency phase-locked loop;

[0024] The radio frequency phase-locked loop converts the second reference clock signal into a first local oscillator signal.

[0025] Furthermore, the baseband processing unit is further used for:

[0026] Acquire a first speed of a preset calibration object; wherein, when the first external interface and the second external interface are not connected, the preset calibration object moves at a uniform speed between the first active antenna unit and the second active antenna unit at the first speed;

[0027] When the first external interface is connected to the second external interface, obtaining a second speed generated by the movement of the preset calibration object between the first active antenna unit and the second active antenna unit;

[0028] Determining a first velocity error of a preset calibration object according to the first velocity and the second velocity;

[0029] determining a first phase error between the first active antenna unit and the second active antenna unit according to the first speed error;

[0030] Before transmitting the third local oscillator signal to the internal frequency mixing device of the second active antenna unit via the third switch, the third amplifier and the fourth switch, the third local oscillator signal is corrected according to the first phase error.

[0031] Further, the second active antenna unit further includes: a second power divider;

[0032] The second active antenna unit transmits the third local oscillator signal to the internal frequency mixing device of the second active antenna unit via the third switch, the third amplifier and the fourth switch, including:

[0033] The third local oscillator signal passing through the fourth switch is transmitted to the second power divider, so that the second power divider divides the third local oscillator signal into a fourth local oscillator signal and a fifth local oscillator signal; the fourth local oscillator signal is transmitted to the internal mixing device of the second active antenna unit.

[0034] Further, it also includes a third active antenna unit;

[0035] The third active antenna unit comprises: a third external interface and a fourth amplifier;

[0036] The second active antenna unit further includes: a fourth external interface and a fifth amplifier;

[0037] The third external interface is connected to the fourth external interface;

[0038] The second active antenna unit is further used to: transmit the fifth local oscillator signal to the third external interface of the third active antenna unit via the fifth amplifier and the fourth external interface;

[0039] The third active antenna unit is used to transmit the fifth local oscillator signal to the internal mixing device of the third active antenna unit via the fourth amplifier.

[0040] Furthermore, the third active antenna unit further includes: a fifth switch and a sixth switch;

[0041] The second active antenna unit further includes: a seventh switch;

[0042] The step of transmitting the fifth local oscillator signal to the third external interface of the third active antenna unit via the fifth amplifier and the fourth external interface includes:

[0043] The fifth local oscillator signal is transmitted to the third external interface of the third active antenna unit via the fifth amplifier, the seventh switch, and the fourth external interface;

[0044] The method of transmitting the fifth local oscillator signal to the internal frequency mixing device of the third active antenna unit via the fourth amplifier includes:

[0045] The fifth local oscillator signal is transmitted to the internal frequency mixing device of the third active antenna unit via the fifth switch, the fourth amplifier and the sixth switch.

[0046] Further, the second active antenna unit further includes: a third power divider and a sixth amplifier;

[0047] The baseband processing unit is further configured to send a second signal to the second active antenna unit when the second active antenna unit is used as a signal input source;

[0048] The second active antenna unit is also used to convert the second signal into a sixth local oscillator signal, and transmit the sixth local oscillator signal to the third power divider, so that the third power divider divides the sixth local oscillator signal into a seventh local oscillator signal and an eighth local oscillator signal; wherein the seventh local oscillator signal is transmitted to the second power divider via the fourth switch, so that the second power divider divides the seventh local oscillator signal into a ninth local oscillator signal and a tenth local oscillator signal; the ninth local oscillator signal is transmitted to the internal frequency mixing device of the second active antenna unit; the tenth local oscillator signal is transmitted via the fifth amplifier, the seventh switch, the fourth external interface and the third external interface of the third active antenna unit; the eighth local oscillator signal is transmitted via the sixth amplifier, the third switch, the second external interface and the first external interface of the first active antenna unit;

[0049] The first active antenna unit is used to transmit the eighth local oscillator signal to the internal frequency mixing device of the first active antenna unit via the first switch, the second amplifier and the second switch;

[0050] The third active antenna unit is used to transmit the tenth local oscillator signal to the internal mixing device of the third active antenna unit via the fifth switch, the fourth amplifier and the sixth switch.

[0051] Furthermore, the baseband processing unit is further used for:

[0052] Obtaining a third speed of a preset calibration object; wherein, when the third external interface and the fourth external interface are not connected, the preset calibration object moves at a uniform speed between the second active antenna unit and the third active antenna unit at the third speed;

[0053] When the third external interface is connected to the fourth external interface, obtaining a fourth speed of the preset calibration object;

[0054] Determine a second speed error of a preset calibration object according to the third speed and the fourth speed;

[0055] determining a second phase error between the second active antenna unit and the third active antenna unit according to the second speed error;

[0056] Before transmitting the fifth local oscillator signal to the internal frequency mixing device of the third active antenna unit via the fifth switch, the fourth amplifier and the sixth switch, the fifth local oscillator signal is corrected according to the second phase error.

[0057] The following beneficial effects are achieved by implementing the present invention:

[0058] The present invention provides a phase synchronization system between multiple base station devices, including: a first active antenna unit, a second active antenna unit and a baseband processing unit; the first active antenna unit includes: a first power divider, a first amplifier, a first external interface, a second amplifier and a second switch; the second active antenna unit includes: a second external interface, a third amplifier and a third switch; the first external interface is connected to the second external interface. By arranging components inside the first active antenna unit and the second active antenna unit, the first active antenna unit provides a first external interface, and the second active antenna unit provides a second external interface. By communicating the first external interface and the second external interface, when the first active antenna unit and the second active antenna unit are combined, only the first signal needs to be sent to the first active antenna unit through the baseband processing unit. After the first active antenna unit independently converts the sent first signal into a local oscillator signal, it directly enters the second external interface through the first external interface, avoiding the second active antenna unit itself converting the first signal into a local oscillator signal, thereby solving the problem of phase jitter and phase asynchronism caused by different internal clock reference sources when the first active antenna unit and the second active antenna unit are jointly sensed. The first active antenna unit and the second active antenna unit both use the local oscillator signal processed by the first active antenna unit, and the signals are homologous, that is, the phase synchronization between the two active antenna units is achieved, thereby improving the perception distance of the two active antenna units. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] Figure 1 It is a schematic diagram of the internal signal processing flow of the traditional active antenna unit joint sensing provided by an embodiment of the present invention.

[0060] Figure 2 It is a schematic diagram of the gain capability obtained by joint transmission and reception between dual active antenna units provided by an embodiment of the present invention.

[0061] Figure 3 It is a structural diagram of a phase synchronization system between multiple base station devices provided by an embodiment of the present invention.

[0062] Figure 4 It is a schematic diagram of an internal signal processing flow for joint perception by a first active antenna unit and a second active antenna unit provided by an embodiment of the present invention.

[0063] Figure 5 It is an internal circuit diagram of a first active antenna unit and a second active antenna unit provided by one embodiment of the present invention.

[0064] Figure 6 It is a schematic diagram of a phase error elimination principle between a first active antenna unit and a second active antenna unit provided by an embodiment of the present invention.

[0065] Figure 7It is a schematic diagram of the internal signal processing flow when the first active antenna unit, the second active antenna unit and the third active antenna unit jointly sense to form a chain connection provided by an embodiment of the present invention.

[0066] Figure 8 It is an internal circuit diagram of the first active antenna unit, the second active antenna unit and the third active antenna unit when the first active antenna unit is used as a signal input source, provided by an embodiment of the present invention.

[0067] Fig. 9 It is a schematic diagram of the internal signal processing flow when the first active antenna unit, the second active antenna unit and the third active antenna unit jointly sense to form a star-type connection provided by an embodiment of the present invention.

[0068] Fig.10 It is an internal circuit diagram of the first active antenna unit, the second active antenna unit and the third active antenna unit when the second active antenna unit is used as a signal input source, provided by one embodiment of the present invention.

[0069] Fig.11 It is a schematic diagram of a phase error elimination principle among a first active antenna unit, a second active antenna unit and a third active antenna unit provided by an embodiment of the present invention.

[0070] Fig.12 It is a schematic diagram of a structure in which each active antenna unit is connected via an external local oscillator generator provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0071] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0072] like Figure 1 As shown, in a traditional AAU (Active Antena Unit) or RRU (Remote Radio Unit), the synchronized clock signal will pass through the following Figure 1 The clock circuit part of any one of the schemes 1-3 described above; it can be seen that no matter which scheme is adopted, the clock between the two active antenna units will pass through the chip or phase-locked loop unit in the dotted box, and pass through each of the units. Due to the inconsistency between the units, the phase difference between the first active antenna unit and the second active antenna unit will be caused, further causing the following Figure 2 The phase fluctuation error shown in the figure causes the problem that the beams cannot be synthesized in the same direction.

[0073] In order to solve the above-mentioned phase inconsistency problem caused by the internal module differences between the active antenna units, the present invention proposes a phase synchronization system between multiple base station devices.

[0074] like Figure 3-Figure 5 As shown, a phase synchronization system between multiple base station devices provided by an embodiment of the present invention includes: a first active antenna unit, a second active antenna unit and a baseband processing unit;

[0075] The first active antenna unit comprises: a first power distributor, a first amplifier, a first external interface and a second amplifier;

[0076] The second active antenna unit includes: a second external interface and a third amplifier;

[0077] The first external interface is connected to the second external interface;

[0078] The baseband processing unit is used to send a first signal to the first active antenna unit when the first active antenna unit is used as a signal input source;

[0079] The first active antenna unit is used to convert the first signal into a first local oscillator signal, and transmit the first local oscillator signal to a first power divider, so that the first power divider divides the first local oscillator signal into a second local oscillator signal and a third local oscillator signal; wherein the second local oscillator signal is transmitted to the internal frequency mixing device of the first active antenna unit via the second switch; and the third local oscillator signal is transmitted to the second external interface of the second active antenna unit via the first amplifier and the first external interface;

[0080] The second active antenna unit is used to transmit the third local oscillator signal to the internal mixing device of the second active antenna unit via the third amplifier.

[0081] In a preferred embodiment, the first active antenna unit also includes: a first switch and a second switch; the second local oscillator signal is transmitted to an internal mixing device of the first active antenna unit; the third local oscillator signal is transmitted to the second external interface of the second active antenna unit via the first amplifier and the first external interface, including: the second local oscillator signal is transmitted to the internal mixing device of the first active antenna unit via the second switch; the third local oscillator signal is transmitted to the second external interface of the second active antenna unit via the first amplifier, the first switch and the first external interface.

[0082] In a preferred embodiment, the second active antenna unit further includes: a third switch and a fourth switch; the transmitting the third local oscillator signal to the internal mixing device of the second active antenna unit via the third amplifier includes: transmitting the third local oscillator signal to the internal mixing device of the second active antenna unit via the third switch, the third amplifier and the fourth switch.

[0083] Specifically, the implementation principle of the present invention is to provide a pair of external interfaces a for the first active antenna unit and a pair of external interfaces b for the second active antenna unit by building hardware circuits in the first active antenna unit and the second active antenna unit, and connect the interfaces a and b through wiring; make any one of the first active antenna unit or the second active antenna unit serve as a signal input source of the synchronization timing signal sent by the baseband processing unit, Figure 4 The example shown in the figure is an example of using the first active antenna unit as the signal input source. A synchronization timing signal is sent to the first active antenna unit through the baseband processing unit, so that the signal at point a drawn out at the first active antenna unit can be directly transmitted to the interface b of the second active antenna unit, so that the clock circuits of the second active antenna unit and the first active antenna unit are completely homologous, eliminating the error caused by the difference in internal devices (digital baseband processing unit and various phase-locked loops) between the second active antenna unit and the first active antenna unit, thereby effectively eliminating the phase error between the first active antenna unit and the second active antenna unit.

[0084] like Figure 5 FIG. 1 is a schematic diagram of the internal circuits and port connections of the first active antenna unit 1 and the second active antenna unit 2 provided in this embodiment. In this embodiment, the first active antenna unit 1 is used as a signal input source for specific description.

[0085] The first active antenna unit 1 includes a first power divider 100, a first amplifier 101, a first switch 102, a first external interface 103, a second amplifier 105, and a second switch 104. The second active antenna unit 2 includes a second external interface 203, a third switch 202, a third amplifier 205, and a fourth switch 204. The first external interface 103 of the first active antenna unit 1 and the second external interface 203 of the second active antenna unit 2. The first external interface 103 and the second external interface 203 are connected by wiring. The baseband processing unit (BBU) is connected to the first active antenna unit 1 and the second active antenna unit 2 respectively by optical fibers. The baseband processing unit sends a first signal to the first active antenna unit.

[0086] In a preferred embodiment, the first active antenna unit further comprises: a signal conversion unit;

[0087] The signal conversion unit includes: a digital baseband processing unit, a digital phase-locked loop, an analog phase-locked loop and a radio frequency phase-locked loop connected in sequence;

[0088] The method for converting the first signal into a first local oscillator signal includes: transmitting the first signal to the digital baseband processing unit so that the digital baseband processing unit converts the first signal into a reference clock signal to be recovered, and transmits the reference clock signal to be recovered to a digital phase-locked loop; the digital phase-locked loop converts the reference clock signal to be recovered into a first reference clock signal, and transmits the first reference clock signal to an analog phase-locked loop; the analog phase-locked loop converts the first reference clock signal into a second reference clock signal, and transmits the second reference clock signal to a radio frequency phase-locked loop; the radio frequency phase-locked loop converts the second reference clock signal into a first local oscillator signal.

[0089] Specifically, the first signal transmitted by the baseband processing unit is a clock signal including phase and time synchronization. When the first active antenna unit 1 is used as the signal input end of the baseband processing unit, the baseband processing unit transmits the above signal to the first active antenna unit 1; when the first active antenna unit 1 receives the clock signal including phase and time synchronization, it is first processed by a digital baseband processing unit such as FPGA, SOC, etc., and after obtaining the clock signal to be recovered, it is processed by a digital phase-locked loop DPLL, so that the signal proximal end of the clock signal to be recovered after being processed by the digital phase-locked loop DPLL obtains a better phase noise performance, and obtains a first reference clock signal with a better phase noise performance. The first reference clock signal is then transmitted to the analog phase-locked loop APLL for processing to convert it into a second reference clock signal, and finally processed by the radio frequency phase-locked loop RFPLL to obtain the corresponding first local oscillator signal. Similarly, if the second active antenna unit 2 is used as the signal input end, when it obtains the corresponding input signal, it also calls the signal conversion unit carried by itself to convert the input signal into the corresponding local oscillator signal.

[0090] After the first active antenna unit 1 obtains the first local oscillator signal, the first local oscillator signal is transmitted to the first power divider 100, and the first power divider 100 divides the first local oscillator signal into a second local oscillator signal and a third local oscillator signal. The second local oscillator signal is transmitted to the internal frequency mixing device of the first active antenna unit 1 through the second switch 104 as the signal flow inside the first active antenna unit; wherein, when the second local oscillator signal is transmitted, the fixed end of the second switch 104 is connected to the moving end 104a. The third local oscillator signal is transmitted to the second external interface 203 through the wiring between the first external interface 103 and the second external interface 203 as the external output signal flow of the first active antenna unit through the first amplifier 101, the first switch 102 and the first external interface 103; wherein, when the third local oscillator signal is transmitted, the fixed end of the first switch 102 is connected to the moving end 102a. The second external interface 203 receives the third local oscillator signal, transmits the third local oscillator signal to the third switch 202, and then transmits the third local oscillator signal to the internal frequency mixer of the second active antenna unit 2 through the third amplifier 205 and the fourth switch 204. When transmitting the third local oscillator signal, the fixed end of the third switch 202 is connected to the moving end 202b, and the fixed end of the fourth switch 204 is connected to the moving end 204b. Through the above process, the transmission of the clock link of the first active antenna unit 1 and the second active antenna unit 2 is completed.

[0091] Since a fixed line is added between the first external interface 103 and the second external interface 203 in the above solution to connect the first active antenna unit 1 and the second active antenna unit 2, considering that the difference in this line will affect the air interface synthesis effect, the following calibration scheme is proposed to address this impact:

[0092] In a preferred embodiment, the baseband processing unit is also used to: obtain a first speed of a preset calibration object; wherein, when the first external interface and the second external interface are not connected, the preset calibration object moves at a uniform speed between the first active antenna unit and the second active antenna unit at the first speed; when the first external interface and the second external interface are connected, obtain a second speed generated by the preset calibration object moving between the first active antenna unit and the second active antenna unit; determine a first speed error of the preset calibration object based on the first speed and the second speed; determine a first phase error between the first active antenna unit and the second active antenna unit based on the first speed error; and correct the third local oscillator signal based on the first phase error before transmitting the third local oscillator signal to the internal mixing device of the second active antenna unit via the third switch, the third amplifier and the fourth switch.

[0093] Specifically, Figure 6As shown in (a), when the first active antenna unit 1 and the second active antenna unit 2 are set up on the site or the site is opened on the existing network, a preset calibration object is provided, which is controlled externally and can be an object such as a drone or a remote control car. The preset calibration object is used to move uniformly between the first active antenna unit 1 and the second active antenna unit 2 at an initial speed V (i.e., the above-mentioned first speed). The first active antenna unit 1 and the second active antenna unit 2 carry out joint perception, so that the two communicate through the first external interface 103 and the second external interface 203. Use any of the methods of the first active antenna unit 1 sending and the second active antenna unit 2 receiving, or the second active antenna unit 2 sending and the first active antenna unit 1 receiving, and then calculate the speed V1 (i.e., the above-mentioned second speed) generated by the preset calibration object moving between the first active antenna unit 1 and the second active antenna unit 2 through the joint perception between the two modules; calculate the first speed error of the preset calibration object according to the formula Δv1=V-V1; calculate the phase error (i.e., the above-mentioned first phase error) between the first active antenna unit 1 and the second active antenna unit 2 by the following formula:

[0094]

[0095] in, is the phase error between the first active antenna unit 1 and the second active antenna unit 2; V1 is the time width of the perception time slot between the first active antenna unit 1 and the second active antenna unit 2 (the time width of Chirp when using frequency modulated continuous wave); λ1 is the perception wavelength of the first active antenna unit 1 and the second active antenna unit 2; Δv1 is the first speed error.

[0096] like Figure 6 As shown in (b), after the first phase error is determined according to the above calculation, in actual use, when the first active antenna unit 1 and the second active antenna unit 2 jointly transmit and receive, the baseband processing unit multiplies the phase of the RF local oscillator signal transmitted to the second active antenna unit 2 through the inter-unit routing by a The redundant phase can be removed. Even if the third local oscillator signal transmitted to the second active antenna unit 2 is a signal corrected by the baseband processing unit according to the first error.

[0097] By implementing the above solution, the influence of phase noise inconsistency between the two active antenna units during joint perception can be eliminated, and the perception ability between the two units can be enhanced. Furthermore, by adding a speed dimension calibration method at the factory or when the station is opened, the phase error caused by the local oscillator routing is eliminated, so that the phase error further reduces the perception ability between the two units.

[0098] In a preferred embodiment, the second active antenna unit also includes: a second power divider; the second active antenna unit transmits the third local oscillator signal to the internal mixing device of the second active antenna unit via the third switch, the third amplifier and the fourth switch, including: transmitting the third local oscillator signal passing through the fourth switch to the second power divider, so that the second power divider divides the third local oscillator signal into a fourth local oscillator signal and a fifth local oscillator signal; transmitting the fourth local oscillator signal to the internal mixing device of the second active antenna unit.

[0099] In a preferred embodiment, it also includes a third active antenna unit; the third active antenna unit includes: a third external interface and a fourth amplifier; the second active antenna unit also includes: a fourth external interface and a fifth amplifier; the third external interface is connected to the fourth external interface; the second active antenna unit is also used to: transmit the fifth local oscillator signal to the third external interface of the third active antenna unit via the fifth amplifier and the fourth external interface; the third active antenna unit is used to transmit the fifth local oscillator signal to the internal mixing device of the third active antenna unit via the fourth amplifier.

[0100] In a preferred embodiment, the third active antenna unit further includes: a fifth switch and a sixth switch; the second active antenna unit further includes: a seventh switch; the step of transmitting the fifth local oscillator signal to the third external interface of the third active antenna unit via the fifth amplifier and the fourth external interface includes: transmitting the fifth local oscillator signal to the third external interface of the third active antenna unit via the fifth amplifier, the seventh switch, and the fourth external interface; the step of transmitting the fifth local oscillator signal to the internal mixing device of the third active antenna unit via the fourth amplifier includes: transmitting the fifth local oscillator signal to the internal mixing device of the third active antenna unit via the fifth switch, the fourth amplifier and the sixth switch.

[0101] Specifically, when there are multiple active antenna units, it is necessary to build a hardware circuit in each active antenna unit, and connect the two units by routing through the external interface of the hardware circuit. In this embodiment, three active antenna units are used as an example, and on this basis, multiple active antenna units can be further expanded and connected, which will not be listed one by one here.

[0102] like Figure 7 Shown and Figure 8 The third active antenna unit 3 shown includes at least a third external interface 303, a fifth switch 302, a fourth amplifier 305 and a sixth switch 304. The second active antenna unit 2 also includes a second power divider 206, a fourth external interface 210, a fifth amplifier 207 and a seventh switch 208. The third external interface 303 and the fourth external interface 210 are connected by wiring.

[0103] After the original circuit is optimized into the above circuit, the second active antenna unit 2, which is used to communicate with the first active antenna unit 1 and the third active antenna unit 3, has two external interfaces. When the first active antenna unit 1 is still used as the signal input source, the three units are constituted as follows Figure 7 Chain type connections shown.

[0104] Since the signal input source has not changed, the signal flow of the local oscillator signal in the first active antenna unit 1 and the second active antenna unit 2 has not changed. After adding the above components, the second active antenna unit 2 transmits the third local oscillator signal through the fourth switch 204 to the second power divider 206; the second power divider 206 divides the third local oscillator signal into two to obtain the fourth local oscillator signal and the fifth local oscillator signal. The fourth local oscillator signal is transmitted to the internal mixer of the second active antenna unit 2. The fifth local oscillator signal is transmitted to the third external interface 303 of the third active antenna unit 3 via the fifth amplifier 207, the seventh switch 208, and the fourth external interface 210; wherein, when transmitting the fifth local oscillator signal, the fixed end of the seventh switch 208 is connected to the moving end 208a, and the other unconnected moving end 208b is connected to a load resistor 209 and then grounded. After the fifth local oscillator signal enters the third external interface 303, it is transmitted to the internal mixing device of the third active antenna unit 3 through the fifth switch 302, the fourth amplifier 305 and the sixth switch 304; wherein, when the fifth local oscillator signal is transmitted, the fixed end of the fifth switch 302 is connected to the moving end 302b, and the fixed end of the sixth switch 304 is connected to the moving end 304b.

[0105] Through the above further optimization process, the transmission of the clock link is completed between the first active antenna unit 1, the second active antenna unit 2 and the third active antenna unit 3.

[0106] In a preferred embodiment, the second active antenna unit further comprises: a third power divider and a sixth amplifier; the baseband processing unit is further used to send a second signal to the second active antenna unit when the second active antenna unit is used as a signal input source; the second active antenna unit is further used to convert the second signal into a sixth local oscillator signal, and transmit the sixth local oscillator signal to the third power divider, so that the third power divider divides the sixth local oscillator signal into a seventh local oscillator signal and an eighth local oscillator signal; wherein the seventh local oscillator signal is transmitted to the second power divider via the fourth switch, so that the second power divider divides the seventh local oscillator signal into a ninth local oscillator signal and a tenth local oscillator signal. oscillation signal; the ninth local oscillation signal is transmitted to the internal mixing device of the second active antenna unit; the tenth local oscillation signal is transmitted via the fifth amplifier, the seventh switch, the fourth external interface and the third external interface of the third active antenna unit; the eighth local oscillation signal is transmitted via the sixth amplifier, the third switch, the second external interface and the first external interface of the first active antenna unit; the first active antenna unit is used to transmit the eighth local oscillation signal via the first switch, the second amplifier and the second switch to the internal mixing device of the first active antenna unit; the third active antenna unit is used to transmit the tenth local oscillation signal via the fifth switch, the fourth amplifier and the sixth switch to the internal mixing device of the third active antenna unit.

[0107] Specifically, Fig. 9 and Fig.10 As shown, when there are three active antenna units, in addition to using the first active antenna unit 1 as the signal input source to form a chain-type connection between the three active antenna units, the signal input source can also be changed from the first active antenna unit 1 to the second active antenna unit 2 to form a star-type connection with the second active antenna unit 2 as the center.

[0108] When the second active antenna unit 2 is used as a signal input source, the second active antenna unit 2 further includes: a third power divider 200 and a sixth amplifier 201 .

[0109] The baseband processing unit sends a second signal to the second active antenna unit 2, and after being processed by the signal conversion module inside the second active antenna unit, a sixth local oscillator signal is obtained and transmitted to the third power divider 200; the third power divider 200 divides the sixth local oscillator signal into two to obtain a seventh local oscillator signal and an eighth local oscillator signal. The seventh local oscillator signal is transmitted to the second power divider 206 via the fourth switch 204, and the second power divider 206 divides the seventh local oscillator signal into two to obtain a ninth local oscillator signal and a tenth local oscillator signal; wherein, when transmitting the seventh local oscillator signal, the fixed end of the fourth switch 204 is connected to the moving end 204a. The ninth local oscillator signal is transmitted to the internal mixing device of the second active antenna unit 2. After the tenth local oscillator signal passes through the fifth amplifier 207, the seventh switch 208, and the fourth external interface 210, it enters the third external interface 303 of the third active antenna unit 3 through the wiring between the fourth external interface 210 and the third external interface 303; wherein, when transmitting the tenth local oscillator signal, the fixed end of the seventh switch 208 is connected to the movable end 208a. After receiving the tenth local oscillator signal, the third external interface 303 transmits it to the internal frequency mixing device of the third active antenna unit 3 through the fifth switch 302, the fourth amplifier 305, and the sixth switch 304; wherein, when transmitting the tenth local oscillator signal, the fixed end of the fifth switch 302 is connected to the movable end 302b, and the fixed end of the sixth switch 304 is connected to the movable end 304b. After passing through the sixth amplifier 201, the third switch 202, and the second external interface 203, the eighth local oscillator signal enters the first external interface 103 of the first active antenna unit 1 through the wiring between the first external interface 103 and the second external interface 203; wherein, when transmitting the eighth local oscillator signal, the fixed end of the third switch 202 is connected to the moving end 202a. After receiving the eighth local oscillator signal, the first external interface 103 transmits it to the internal frequency mixing device of the first active antenna unit 1 through the first switch 102, the second amplifier 105, and the second switch 104; wherein, when transmitting the eighth local oscillator signal, the fixed end of the first switch 102 is connected to the moving end 102b, and the fixed end of the second switch 104 is connected to the moving end 104b.

[0110] Through the above process, the transmission of the clock link is completed between the first active antenna unit 1, the second active antenna unit 2 and the third active antenna unit 3.

[0111] Similarly, after the third active antenna unit 3 is added, the phase error between the second active antenna unit 2 and the third active antenna unit 3 caused by the wiring needs to be eliminated.

[0112] In a preferred embodiment, the baseband processing unit is also used to: obtain a third speed of a preset calibration object; wherein, when the third external interface is not connected to the fourth external interface, the preset calibration object moves at a uniform speed between the second active antenna unit and the third active antenna unit at the third speed; when the third external interface is connected to the fourth external interface, obtain a fourth speed of the preset calibration object; determine a second speed error of the preset calibration object according to the third speed and the fourth speed; determine a second phase error between the second active antenna unit and the third active antenna unit according to the second speed error; and correct the fifth local oscillator signal according to the second phase error before transmitting the fifth local oscillator signal to the internal mixing device of the third active antenna unit via the fifth switch, the fourth amplifier and the sixth switch.

[0113] Specifically, Fig.11 As shown in (a), when the second active antenna unit 2 and the third active antenna unit 3 are set up or the existing network is opened, a preset calibration object that is the same as that used in the first active antenna unit 1 and the second active antenna unit 2 is provided. The preset calibration object is used to move uniformly between the second active antenna unit 2 and the third active antenna unit 3 at an initial speed V (i.e., the third speed mentioned above, where the third speed is the same as the first speed mentioned above). It is assumed that the second active antenna unit 2 and the third active antenna unit 3 carry out joint sensing, so that the two communicate through the fourth external interface 210 and the third external interface 303. Use any of the following methods: the second active antenna unit 2 transmits and the third active antenna unit 3 receives, or the third active antenna unit 3 transmits and the second active antenna unit 2 receives, and then calculate the speed V2 (i.e., the fourth speed) generated by the movement of the preset calibration object between the second active antenna unit 2 and the third active antenna unit 3 through joint perception between the two modules; calculate the second speed error of the preset calibration object according to the formula Δv2=V-V2; calculate the phase error (i.e., the second phase error) between the second active antenna unit 2 and the third active antenna unit 3 by the following formula:

[0114]

[0115] in, is the phase error between the second active antenna unit 2 and the third active antenna unit 3; T2 is the time width of the perception time slot between the second active antenna unit 2 and the third active antenna unit 3 (the time width of Chirp when using frequency modulated continuous wave); λ2 is the perception wavelength of the second active antenna unit 2 and the third active antenna unit 3; Δv2 is the second speed error.

[0116] like Fig.11As shown in (b), after the second phase error is determined according to the above calculation, in actual use, when the second active antenna unit 2 and the third active antenna unit 3 jointly transmit and receive, the baseband processing unit multiplies the phase of the RF local oscillator signal transmitted to the third active antenna unit 3 through the inter-unit wiring by a The redundant phase can be removed. Even if the fifth local oscillator signal transmitted to the third active antenna unit 3 is a signal corrected by the baseband processing unit according to the second error.

[0117] The above scheme can also be used for the second active antenna unit 2 to transmit, the first active antenna unit 1 to receive and the third active antenna unit 3 to receive. Calculating the phase error between the second active antenna unit 2 and the first active antenna unit 1 and calculating the phase error between the second active antenna unit 2 and the third active antenna unit 3 are the same as the above scheme, and will not be repeated here.

[0118] Preferably, when there are too many active antenna unit devices that need to be jointly sensed, Fig.12 The external local oscillator generator shown in the figure enables the local oscillator generator to send the same local oscillator signal to each active antenna unit connected thereto, so that the local oscillator signal enters the external interface of the active antenna unit and is directly transmitted to the internal frequency mixing device of the active antenna unit through the internal circuit. For example: when the local oscillator generator sends the local oscillator signal to AAU1 (i.e. the first active antenna unit 1 mentioned above), the first external interface 103 of the first active antenna unit 1 receives the local oscillator signal, connects the fixed end of the first switch 102 with the moving end 102b, and after the local oscillator signal is transmitted to the second amplifier 105, the fixed end of the second switch 104 is connected with the moving end 104b, so that the local oscillator signal is transmitted to the internal frequency mixing device of the first active antenna unit 1. The internal transmission of the rest of AAU2, AAU3, etc. is the same as that of AAU1, and will not be repeated here.

[0119] In addition, it should be added that, without considering the cost, the hardware circuits built into the active antenna unit can be set as follows Figure 8 and Fig.10 The circuit structure of the second active antenna unit 2 shown in FIG. 2 includes all components required for signal transmission. In the above description, only the minimum components required to ensure signal transmission are described.

[0120] It should be noted that the system embodiment described above is merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. In addition, in the drawings of the system embodiment provided by the present invention, the connection relationship between the modules indicates that there is a communication connection between them, which may be specifically implemented as one or more communication buses or signal lines. A person of ordinary skill in the art may understand and implement it without paying any creative effort.

[0121] Those skilled in the art can clearly understand that for the sake of convenience and brevity, the specific working process of the device described above can refer to the corresponding process in the aforementioned method embodiment, and will not be repeated here.

[0122] The above is a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several improvements and modifications without departing from the principle of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A phase synchronization system between multiple base station devices, characterized in that: include: A first active antenna unit, a second active antenna unit, a baseband processing unit and a third active antenna unit; The first active antenna unit includes: a first power divider, a first amplifier, a first external interface, a second amplifier, a first switch, a second switch and a signal conversion unit; wherein the signal conversion unit includes a digital baseband processing unit, a digital phase-locked loop, an analog phase-locked loop and a radio frequency phase-locked loop connected in sequence; The second active antenna unit includes: a second external interface, a third amplifier, a third switch, a fourth switch, a fourth external interface, a fifth amplifier and a second power divider; The third active antenna unit comprises: a third external interface and a fourth amplifier; The first external interface is connected to the second external interface, and the third external interface is connected to the fourth external interface; The baseband processing unit is used to send a first signal to the first active antenna unit when the first active antenna unit is used as a signal input source; The first active antenna unit is used to transmit the first signal to the digital baseband processing unit, so that the digital baseband processing unit converts the first signal into a reference clock signal to be recovered, and transmits the reference clock signal to be recovered to a digital phase-locked loop; the digital phase-locked loop converts the reference clock signal to be recovered into a first reference clock signal, and transmits the first reference clock signal to an analog phase-locked loop; the analog phase-locked loop converts the first reference clock signal into a second reference clock signal, and transmits the second reference clock signal to a radio frequency phase-locked loop; the radio frequency phase-locked loop converts the second reference clock signal into a first local oscillator signal, and transmits the first local oscillator signal to a first power divider, so that the first power divider divides the first local oscillator signal into a second local oscillator signal and a third local oscillator signal; wherein the second local oscillator signal is transmitted to the internal mixing device of the first active antenna unit via the second switch; the third local oscillator signal is transmitted to the second external interface of the second active antenna unit via the first amplifier, the first switch and the first external interface; The baseband processing unit is further used to: obtain a first speed of a preset calibration object; wherein, when the first external interface is not connected to the second external interface, the preset calibration object moves at a uniform speed between the first active antenna unit and the second active antenna unit at the first speed; when the first external interface is connected to the second external interface, obtain a second speed generated by the preset calibration object moving between the first active antenna unit and the second active antenna unit; determine a first speed error of the preset calibration object according to the first speed and the second speed; determine a first phase error between the first active antenna unit and the second active antenna unit according to the first speed error; and correct the third local oscillator signal according to the first phase error before transmitting the third local oscillator signal to the internal mixing device of the second active antenna unit via the third switch, the third amplifier and the fourth switch; The second active antenna unit is used to transmit the third local oscillator signal to the internal mixing device of the second active antenna unit via the third switch, the third amplifier and the fourth switch; wherein the third local oscillator signal passing through the fourth switch is transmitted to the second power divider, so that the second power divider divides the third local oscillator signal into a fourth local oscillator signal and a fifth local oscillator signal; the fourth local oscillator signal is transmitted to the internal mixing device of the second active antenna unit; the fifth local oscillator signal is transmitted to the third external interface of the third active antenna unit via the fifth amplifier and the fourth external interface, so that the third active antenna unit transmits the fifth local oscillator signal to the internal mixing device of the third active antenna unit via the fourth amplifier.

2. A phase synchronization system between multiple base station devices as claimed in claim 1, characterized in that: The third active antenna unit further includes: a fifth switch and a sixth switch; The second active antenna unit further includes: a seventh switch; The step of transmitting the fifth local oscillator signal to the third external interface of the third active antenna unit via the fifth amplifier and the fourth external interface includes: The fifth local oscillator signal is transmitted to the third external interface of the third active antenna unit via the fifth amplifier, the seventh switch, and the fourth external interface; The method of transmitting the fifth local oscillator signal to the internal frequency mixing device of the third active antenna unit via the fourth amplifier includes: The fifth local oscillator signal is transmitted to the internal frequency mixing device of the third active antenna unit via the fifth switch, the fourth amplifier and the sixth switch.

3. A phase synchronization system between multiple base station devices as claimed in claim 2, characterized in that: The second active antenna unit further comprises: a third power divider and a sixth amplifier; The baseband processing unit is further configured to send a second signal to the second active antenna unit when the second active antenna unit is used as a signal input source; The second active antenna unit is also used to convert the second signal into a sixth local oscillator signal, and transmit the sixth local oscillator signal to the third power divider, so that the third power divider divides the sixth local oscillator signal into a seventh local oscillator signal and an eighth local oscillator signal; wherein the seventh local oscillator signal is transmitted to the second power divider via the fourth switch, so that the second power divider divides the seventh local oscillator signal into a ninth local oscillator signal and a tenth local oscillator signal; the ninth local oscillator signal is transmitted to the internal frequency mixing device of the second active antenna unit; the tenth local oscillator signal is transmitted via the fifth amplifier, the seventh switch, the fourth external interface and the third external interface of the third active antenna unit; the eighth local oscillator signal is transmitted via the sixth amplifier, the third switch, the second external interface and the first external interface of the first active antenna unit; The first active antenna unit is used to transmit the eighth local oscillator signal to the internal mixing device of the first active antenna unit via the first switch, the second amplifier and the second switch; The third active antenna unit is used to transmit the tenth local oscillator signal to the internal mixing device of the third active antenna unit via the fifth switch, the fourth amplifier and the sixth switch.

4. A phase synchronization system between multiple base station devices as claimed in claim 3, characterized in that: The baseband processing unit is further used for: Obtaining a third speed of a preset calibration object; wherein, when the third external interface and the fourth external interface are not connected, the preset calibration object moves at a uniform speed between the second active antenna unit and the third active antenna unit at the third speed; When the third external interface is connected to the fourth external interface, obtaining a fourth speed of the preset calibration object; Determining a second speed error of a preset calibration object according to the third speed and the fourth speed; determining a second phase error between the second active antenna unit and the third active antenna unit according to the second speed error; Before transmitting the fifth local oscillator signal to the internal frequency mixing device of the third active antenna unit via the fifth switch, the fourth amplifier and the sixth switch, the fifth local oscillator signal is corrected according to the second phase error.

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