A mechanical servo digital phased array system

Abstract

The present invention discloses a mechanical servo digital phased array system, including a baseband processing module and a radio frequency remote module, wherein the baseband processing module is connected to the radio frequency remote module, wherein the radio frequency remote module includes a first control unit, a second control unit, a processor, a transceiver, a TR component and an antenna isolator, and in terms of the transmission direction, the baseband processing module sends baseband data to the first control unit through a pair of optical fibers, and the baseband data is shaped in the first control unit and sent to the transceiver. The present invention discloses a mechanical servo digital phased array system, which forms a beam in a digital manner, thereby capturing and tracking an aerial node, and communicating with the aerial node by controlling the beam.

Description

Technical Field

[0001] The invention belongs to the technical field of digital phased array control, and in particular relates to a mechanical servo digital phased array system. Background Art

[0002] As phased array systems are increasingly used in military and civilian electronic systems, phased array technology itself is also constantly developing. However, many existing phased array systems use analog phased arrays to form beams, which have disadvantages such as small dynamic range, low beam accuracy, and difficulty in forming multiple beams simultaneously.

[0003] Therefore, further improvements are made to the above problems. Summary of the invention

[0004] The main purpose of the present invention is to provide a mechanical servo digital phased array system, which forms a beam in a digital manner to capture and track an aerial node and communicate with the aerial node by controlling the beam.

[0005] To achieve the above object, the present invention provides a mechanical servo digital phased array system, comprising a baseband processing module (BBU) and a radio remote unit (RRU), wherein the baseband processing module is connected to the radio remote unit, wherein:

[0006] The radio remote module includes a first control unit (FPGA1), a second control unit (FPGA2), a processor (DSP), a transceiver (AD9361), a TR component and an antenna isolator, wherein:

[0007] In the transmission direction, the baseband processing module (FPGA0) sends the baseband data to the first control unit through a pair of optical fibers, the baseband data is shaped in the first control unit and sent to the transceiver, and after the transceiver completes the up-conversion, the analog intermediate frequency data is sent to the TR component, and the TR component completes the secondary frequency conversion and then sends it to the corresponding antenna array element connected to the antenna isolator;

[0008] For the receiving direction, the RF analog signal received from the antenna array element enters the TR component through the antenna isolator, and the TR component performs a down-conversion and sends the analog intermediate frequency signal to the transceiver, so that after the transceiver completes the secondary frequency conversion, the baseband IQ data is sent to the first control unit, so that after the shaping processing is completed in the first control unit, the synthesized baseband data is sent to the baseband processing module;

[0009] The processor is used to implement the correction algorithm, DOA estimation, shaping vector generation and configuration of the transceiver, and the first control unit sends the processed array data to the processor in real time (via the RapidIO interface), thereby completing the correction and DOA estimation;

[0010] The second control unit is used for interface expansion to control multiple TR components to complete the shaping and correction process (the main modules of FPGA2 are gtx, tr_ctrl_top and fs_if. Among them, gtx is responsible for communicating with FPGA1 and receiving TR control instructions from FPGA1. TR_if1..8 is responsible for directly communicating with TR components 1 to 8 and actually generating TR control interface signals. The fs_if module is responsible for controlling the frequency synthesis interface).

[0011] As a further preferred technical solution of the above technical solution, the first control unit includes a GTX interface, a sending shaping module, a receiving shaping module, a correction top-level module, a sending (9361) interface, a receiving (9361) interface, a sending shaping vector update module, a sending shaping vector update module, a DOA data extraction module, a DSP interface module, an SRIO interface module, a TR control GTX interface module, a servo control interface module and an initial scanning module, wherein:

[0012] For the GTX interface, data is exchanged with the baseband processing module to transmit baseband data, including modulated baseband data sent and unmodulated baseband data received; the interface is also used to transmit the content of the baseband processing module to the radio remote module, including control signals and clock synchronization signals;

[0013] For the transmission shaping module, the baseband transmission data from the baseband processing module are shaped and weighted according to the current frame shaping vector from the processor, so as to obtain the array data of (8) array elements; (in order to reduce the amount of calculation) the correction vector is first merged with the shaping vector, and then the merged weighted vector is shaped with the baseband data;

[0014] For the receiving shaping module, the array data and the corrected shaping vector are multiplied and added to combine the received shaped baseband data (the function of this module is the same as that of the sending shaping module, but in the opposite direction);

[0015] The correction top-level module is used to implement the correction process, receives the correction control instruction from the baseband processing module, starts the correction process, sends the pre-stored correction waveform on each array element, uses the signal received by the adjacent array element to perform amplitude and phase correction between the array elements, and outputs the correction result in the form of a correction vector;

[0016] For the transmission interface module, the array element signal is formatted and output according to the data format required by (9361), directly connected to the transceiver and the data packet is output in the form of LVDS level;

[0017] For the sending shaping vector update module, the sending shaping vector is updated according to the correction and DOA results;

[0018] For the receiving beamforming vector update module, the receiving beamforming vector is updated according to the correction and DOA results;

[0019] The receiving interface module is directly connected to the transceiver, receives the data packets in the receiving direction of the transceiver in the form of LVDS level, and converts the data transmission format of the transceiver into the usual I / Q data format;

[0020] The DOA data extraction module is used to extract the data used to calculate the DOA from the data stream and output it one by one according to the agreed method;

[0021] For the DSP interface module, it schedules various types of data between the processor, implements bus arbitration through the same SRIO bus, and interacts with the processor to aggregate the data of each module;

[0022] The SRIO interface module (which instantiates 4X 3.125G SRIO interfaces) is used to exchange data with the processor;

[0023] For the TR control GTX interface module, (this module is responsible for communicating with another K7 325T FPGA to control the TR control interface on another FPGA. Since the number of user IOs of one FPGA is limited and cannot meet the needs of controlling 8 TRs separately, another K7 FPGA is added specifically for expanding and instantiating the TR control interface;

[0024] For the servo control interface, it controls the external turntable servo system and receives the control instruction from the processor, thereby controlling the turntable servo mechanism and cooperating to complete the system functions of initial scanning and tracking;

[0025] For the initial scanning module, the initial scanning work after power-on is completed by controlling the turntable, and the turntable is positioned according to the scanning results to roughly capture the position and direction of the aerial node.

[0026] As a further preferred technical solution of the above technical solution, AGC automatic gain control is performed, wherein:

[0027] AGC is completed through a 100us preamble signal at the beginning of each frame. The 100us preamble consists of 10us channel silence and 90us repeated detection sequence. The AGC control state machine has two states, namely the adjustment state and the locking state. In the adjustment state, the AGC performs open-loop dynamic adjustment according to the received spatial signal strength; in the locked state, the AGC no longer adjusts and all controllable gains are locked; the AGC is in the adjustment state before the signal arrives, and when the repeated detection sequence after the silence is received, the AGC adjustment is performed; when the system completes the signal arrival detection, that is, after the correlation operation confirms the peak value, the AGC enters the locking state, and when a frame is received, the AGC returns to the adjustment state.

[0028] As a further preferred technical solution of the above technical solution, for AGC automatic gain control, the switching condition between the two states is:

[0029] Lock state entry condition: signal arrival detection confirmation

[0030] Conditions for adjusting the status: frame duration counting is completed;

[0031] For the adjustment state, when the AGC module is in the adjustment state, the adjustment mechanism is always working. There are 3 detection points in the AGC module, which are located at the RF, IF and baseband respectively. The RF and IF detection points are located in the TR component, and are output through analog RSSI signals and enter the first control unit after passing through AD. The baseband detection point is located in the first control unit; there are also 3 control points of AGC, which are located before the 3 detection points, namely RF, IF and baseband. The RF and IF control points are located in the TR component, and a 30dB digitally controlled attenuator with an accuracy of 1dB is used. The baseband control point is in the transceiver, and the 3 control points are adjusted according to the strength of the signals at their corresponding detection points.

[0032] For the locked state, the locked state is entered in a certain order. First, the intermediate frequency gain is locked immediately, after T1+T2 (intermediate frequency detection delay + intermediate frequency digital control attenuation delay), the radio frequency gain is locked, after T3+T4 (radio frequency detection delay + intermediate frequency digital control attenuation delay), the baseband gain is locked. The locking process is as follows:

[0033] After the signal arrival detection is confirmed, first release the IF and RF attenuators (set to zero), and then detect RSSI after the control takes effect. Take the 16-bit average of the detection results, and configure the attenuator according to the detection results (first attenuate the IF, then attenuate the RF). If both levels of RSSI are saturated in the first detection result, fully attenuate both levels of attenuators. After the control takes effect, re-detect RSSI, and also take the 16-bit average. Adjust the RF attenuation according to the second RSSI detection result, and lock the baseband gain after the control takes effect.

[0034] As a further preferred technical solution of the above technical solution, electromechanical combined control is carried out, which is specifically implemented as follows:

[0035] (Mechanical scanning is the beam scanning achieved by the antenna making mechanical movements according to instructions. The mechanical scanning rate of antennas with large size and mass is not high, which affects the data rate of the antenna. During mechanical scanning, the frequency of rotation or swing of an antenna is about several to dozens of times per minute. In principle, both planar antennas and array antennas can be mechanically scanned.

[0036] The antenna does not make mechanical movements during electronic scanning. The beam transmitted or received by the antenna can change direction without inertia in a set airspace. In addition, the antenna can also change the lobe shape, such as widening the main lobe to increase the probability of finding the search. The electronic scanning system is only applicable to array antennas.

[0037] This beam control scheme uses electromechanical joint control for scanning. Mechanical scanning is completed by a one-dimensional servo turntable, and electrical scanning is completed by beamforming. The one-dimensional servo turntable used in this scheme adopts a mechanical structure with a fixed pitch angle. The array is at a fixed inclination angle with the horizontal plane. The turntable motor drives the array to scan in the horizontal direction. The scanning mode supports multiple functions such as circumferential scanning, fan scanning, and positioning. The positioning accuracy is as high as 0.01°, and the scanning speed can be specified by the host computer)

[0038] A. The pitch angle is fixed, and the motor drives the azimuth angle to 0°;

[0039] B. The azimuth angle is scanned from the 1st to the 24th level in sequence;

[0040] C. Determine the initial direction of the incoming wave based on the received signal energy;

[0041] D. Mechanically adjust the antenna array to the target position for data communication;

[0042] E. If the communication quality is lower than a preset threshold, the received signal is used to estimate the angle of arrival (DOA);

[0043] F. Based on the obtained results, the specified angle beamforming is completed by controlling the phase of the analog-digital hybrid antenna array;

[0044] G. Carry out data communication.

[0045] As a further preferred technical solution of the above technical solution, step tracking is performed. When the DOA algorithm obtains the accurate incoming wave angle, the mechanical pointing of the antenna array needs to be adjusted. The RF remote module uses each receiving time slot to do DOA, and adjusts the angle of the servo turntable in real time according to the DOA result to complete the real-time tracking of the antenna beam in the horizontal direction. The pitch direction is beamformed according to the DOA result to ensure that the beam always points to the direction of the aerial node. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 It is a structural schematic diagram of a mechanical servo digital phased array system of the present invention.

[0047] Figure 2 It is a schematic diagram of a hardware platform of a mechanical servo digital phased array system of the present invention.

[0048] Figure 3 It is a schematic diagram of a first control unit of a mechanical servo digital phased array system of the present invention.

[0049] Figure 4 It is a schematic diagram of a second control unit of a mechanical servo digital phased array system of the present invention.

[0050] Figure 5 It is a control function block diagram of the AGC adjustment state of a mechanical servo digital phased array system of the present invention.

[0051] Figure 6 It is a timing diagram of entering the AGC locking state of a mechanical servo digital phased array system of the present invention. DETAILED DESCRIPTION

[0052] The following description is used to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are only examples, and those skilled in the art can think of other obvious variations. The basic principles of the present invention defined in the following description can be applied to other embodiments, variations, improvements, equivalents, and other technical solutions that do not deviate from the spirit and scope of the present invention.

[0053] In the preferred embodiments of the present invention, those skilled in the art should note that the aerial nodes and the like involved in the present invention may be regarded as prior art.

[0054] Preferred embodiments.

[0055] The mechanical servo digital phased array system is a ground node device used for wireless communication with the aerial node.

[0056] Among them, the aerial node contains an omnidirectional antenna, which is used to periodically send signaling to facilitate the ground node to capture and track and communicate.

[0057] The ground node equipment includes a servo turntable, a BBU node, and an RRU node. The RRU node is a beam control device. The ground node is responsible for capturing and tracking the aerial node and communicating with the aerial node by controlling the beam.

[0058] The present invention discloses a mechanical servo digital phased array system, comprising a baseband processing module (BBU) and a radio remote unit (RRU), wherein the baseband processing module is connected to the radio remote unit, wherein:

[0059] The radio remote module includes a first control unit (FPGA1), a second control unit (FPGA2), a processor (DSP), a transceiver (AD9361), a TR component and an antenna isolator, wherein:

[0060] In the transmission direction, the baseband processing module (FPGA0) sends the baseband data to the first control unit through a pair of optical fibers, the baseband data is shaped in the first control unit and sent to the transceiver, and after the transceiver completes the up-conversion, the analog intermediate frequency data is sent to the TR component, and the TR component completes the secondary frequency conversion and then sends it to the corresponding antenna array element connected to the antenna isolator;

[0061] For the receiving direction, the RF analog signal received from the antenna array element enters the TR component through the antenna isolator, and the TR component performs a down-conversion and sends the analog intermediate frequency signal to the transceiver, so that after the transceiver completes the secondary frequency conversion, the baseband IQ data is sent to the first control unit, so that after the shaping processing is completed in the first control unit, the synthesized baseband data is sent to the baseband processing module;

[0062] The processor is used to implement the correction algorithm, DOA estimation, shaping vector generation and configuration of the transceiver, and the first control unit sends the processed array data to the processor in real time (via the RapidIO interface), thereby completing the correction and DOA estimation;

[0063] The second control unit is used for interface expansion to control multiple TR components to complete the shaping and correction process (the main modules of FPGA2 are gtx, tr_ctrl_top and fs_if. Among them, gtx is responsible for communicating with FPGA1 and receiving TR control instructions from FPGA1. TR_if1..8 is responsible for directly communicating with TR components 1 to 8 and actually generating TR control interface signals. The fs_if module is responsible for controlling the frequency synthesis interface).

[0064] Specifically, the first control unit includes a GTX interface, a sending shaping module, a receiving shaping module, a correction top-level module, a sending (9361) interface, a receiving (9361) interface, a sending shaping vector update module, a sending shaping vector update module, a DOA data extraction module, a DSP interface module, an SRIO interface module, a TR control GTX interface module, a servo control interface module and an initial scanning module, wherein:

[0065] For the GTX interface, data is exchanged with the baseband processing module to transmit baseband data, including modulated baseband data sent and unmodulated baseband data received; the interface is also used to transmit the content of the baseband processing module to the radio remote module, including control signals and clock synchronization signals;

[0066] For the transmission shaping module, the baseband transmission data from the baseband processing module are shaped and weighted according to the current frame shaping vector from the processor, so as to obtain the array data of (8) array elements; (in order to reduce the amount of calculation) the correction vector is first merged with the shaping vector, and then the merged weighted vector is shaped with the baseband data;

[0067] For the receiving shaping module, the array data and the corrected shaping vector are multiplied and added to combine the received shaped baseband data (the function of this module is the same as that of the sending shaping module, but in the opposite direction);

[0068] The correction top-level module is used to implement the correction process, receives the correction control instruction from the baseband processing module, starts the correction process, sends the pre-stored correction waveform on each array element, uses the signal received by the adjacent array element to perform amplitude and phase correction between the array elements, and outputs the correction result in the form of a correction vector;

[0069] For the transmission interface module, the array element signal is formatted and output according to the data format required by (9361), directly connected to the transceiver and the data packet is output in the form of LVDS level;

[0070] For the sending shaping vector update module, the sending shaping vector is updated according to the correction and DOA results;

[0071] For the receiving beamforming vector update module, the receiving beamforming vector is updated according to the correction and DOA results;

[0072] The receiving interface module is directly connected to the transceiver, receives the data packets in the receiving direction of the transceiver in the form of LVDS level, and converts the data transmission format of the transceiver into the usual I / Q data format;

[0073] The DOA data extraction module is used to extract the data used to calculate the DOA from the data stream and output it one by one according to the agreed method;

[0074] For the DSP interface module, it schedules various types of data between the processor, implements bus arbitration through the same SRIO bus, and interacts with the processor to aggregate the data of each module;

[0075] The SRIO interface module (which instantiates 4X 3.125G SRIO interfaces) is used to exchange data with the processor;

[0076] For the TR control GTX interface module, (this module is responsible for communicating with another K7 325T FPGA to control the TR control interface on another FPGA. Since the number of user IOs of one FPGA is limited and cannot meet the needs of controlling 8 TRs separately, another K7 FPGA is added specifically for expanding and instantiating the TR control interface;

[0077] For the servo control interface, it controls the external turntable servo system and receives the control instruction from the processor, thereby controlling the turntable servo mechanism and cooperating to complete the system functions of initial scanning and tracking;

[0078] For the initial scanning module, the initial scanning work after power-on is completed by controlling the turntable, and the turntable is positioned according to the scanning results to roughly capture the position and direction of the aerial node.

[0079] More specifically, an AGC automatic gain control is performed, wherein:

[0080] AGC is completed through a 100us preamble signal at the beginning of each frame. The 100us preamble consists of 10us channel silence and 90us repeated detection sequence. The AGC control state machine has two states, namely the adjustment state and the locking state. In the adjustment state, the AGC performs open-loop dynamic adjustment according to the received spatial signal strength; in the locked state, the AGC no longer adjusts and all controllable gains are locked; the AGC is in the adjustment state before the signal arrives, and when the repeated detection sequence after the silence is received, the AGC adjustment is performed; when the system completes the signal arrival detection, that is, after the correlation operation confirms the peak value, the AGC enters the locking state, and when a frame is received, the AGC returns to the adjustment state.

[0081] Furthermore, for AGC automatic gain control, the switching condition between the two states is:

[0082] Lock state entry condition: signal arrival detection confirmation

[0083] Conditions for adjusting the status: frame duration counting is completed;

[0084] For the adjustment state, when the AGC module is in the adjustment state, the adjustment mechanism is always working. There are 3 detection points in the AGC module, which are located at the RF, IF and baseband respectively. The RF and IF detection points are located in the TR component, and are output through analog RSSI signals and enter the first control unit after passing through AD. The baseband detection point is located in the first control unit; there are also 3 control points of AGC, which are located before the 3 detection points, namely RF, IF and baseband. The RF and IF control points are located in the TR component, and a 30dB digitally controlled attenuator with an accuracy of 1dB is used. The baseband control point is in the transceiver, and the 3 control points are adjusted according to the strength of the signals at their corresponding detection points.

[0085] For the locked state, the locked state is entered in a certain order. First, the intermediate frequency gain is locked immediately, after T1+T2 (intermediate frequency detection delay + intermediate frequency digital control attenuation delay), the radio frequency gain is locked, after T3+T4 (radio frequency detection delay + intermediate frequency digital control attenuation delay), the baseband gain is locked. The locking process is as follows:

[0086] After the signal arrival detection is confirmed, first release the IF and RF attenuators (set to zero), and then detect RSSI after the control takes effect. Take the 16-bit average of the detection results, and configure the attenuator according to the detection results (first attenuate the IF, then attenuate the RF). If both levels of RSSI are saturated in the first detection result, fully attenuate both levels of attenuators. After the control takes effect, re-detect RSSI, and also take the 16-bit average. Adjust the RF attenuation according to the second RSSI detection result, and lock the baseband gain after the control takes effect.

[0087] Furthermore, electromechanical joint control is performed, and electromechanical joint scanning is specifically implemented as follows:

[0088] (Mechanical scanning is the beam scanning achieved by the antenna making mechanical movements according to instructions. The mechanical scanning rate of antennas with large size and mass is not high, which affects the data rate of the antenna. During mechanical scanning, the frequency of rotation or swing of an antenna is about several to dozens of times per minute. In principle, both planar antennas and array antennas can be mechanically scanned.

[0089] The antenna does not make mechanical movements during electronic scanning. The beam transmitted or received by the antenna can change direction without inertia in a set airspace. In addition, the antenna can also change the lobe shape, such as widening the main lobe to increase the probability of finding the search. The electronic scanning system is only applicable to array antennas.

[0090] This beam control scheme uses electromechanical joint control for scanning. Mechanical scanning is completed by a one-dimensional servo turntable, and electrical scanning is completed by beamforming. The one-dimensional servo turntable used in this scheme adopts a mechanical structure with a fixed pitch angle. The array is at a fixed inclination angle with the horizontal plane. The turntable motor drives the array to scan in the horizontal direction. The scanning mode supports multiple functions such as circumferential scanning, fan scanning, and positioning. The positioning accuracy is as high as 0.01°, and the scanning speed can be specified by the host computer)

[0091] A. The pitch angle is fixed, and the motor drives the azimuth angle to 0°;

[0092] B. The azimuth angle is scanned from the 1st to the 24th level in sequence;

[0093] C. Determine the initial direction of the incoming wave based on the received signal energy;

[0094] D. Mechanically adjust the antenna array to the target position for data communication;

[0095] E. If the communication quality is lower than a preset threshold, the received signal is used to estimate the angle of arrival (DOA);

[0096] F. Based on the obtained results, the specified angle beamforming is completed by controlling the phase of the analog-digital hybrid antenna array;

[0097] G. Carry out data communication.

[0098] Preferably, step tracking is performed. When the DOA algorithm obtains the accurate incoming wave angle, the mechanical pointing of the antenna array needs to be adjusted. The RF remote module uses each receiving time slot to do DOA. According to the DOA result, the angle of the servo turntable is adjusted in real time to complete the real-time tracking of the antenna beam in the horizontal direction. The pitch direction is beamformed according to the DOA result so that the beam always points to the direction of the aerial node.

[0099] Preferably, it also includes a control interface for a mechanical servo, wherein:

[0100] a) The maximum rotation speed of the mechanical servo turntable is 360° / s, the acceleration is 50° / s, and the movement mode is:

[0101] The host computer specifies the motion arc, and the mechanical servo turntable accelerates first and then decelerates:

[0102] b) The control mode of the mechanical servo turntable is: RS422 serial port, the control baud rate is designed to be 115200,

[0103] If the data volume is 8 bytes, the control time is:

[0104]

[0105] c) The control time is calculated as follows:

[0106] Assume the target movement distance is α and the running time is t, then the relationship between time and distance is:

[0107]

[0108] Taking the maximum movement of 360° as an example, the required rotation time is 5.37s. When the highest speed point is 180°, the speed value is 134.16°, which is less than the maximum speed limit of 360° / s.

[0109] When running at maximum speed, the angle for the 200ms run is 26°, which is less than half the beam angle (45°).

[0110] Therefore, during the signal search process, the signal search can be performed while the operation is in progress.

[0111] It is worth mentioning that the technical features such as aerial nodes involved in the patent application of this invention should be regarded as prior art. The specific structure, working principle and possible control method and spatial layout method of these technical features can be selected by conventional methods in the field, and should not be regarded as the inventive point of this patent. This patent will not be further elaborated.

[0112] For those skilled in the art, it is still possible to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A mechanical servo digital phased array system, characterized in that: It includes a baseband processing module and a radio remote module, wherein the baseband processing module is connected to the radio remote module, wherein: The radio remote module includes a first control unit, a second control unit, a processor, a transceiver, a TR component and an antenna isolator, wherein: In the transmission direction, the baseband processing module sends the baseband data to the first control unit through a pair of optical fibers, the baseband data is shaped in the first control unit and sent to the transceiver, the transceiver completes up-conversion, sends the analog intermediate frequency data to the TR component, and the TR component completes secondary frequency conversion and then sends it to the antenna array element through the antenna isolator; For the receiving direction, the RF analog signal received from the antenna array element enters the TR component through the antenna isolator, and the TR component performs a down-conversion and sends the analog intermediate frequency signal to the transceiver, so that after the transceiver completes the secondary frequency conversion, the baseband IQ data is sent to the first control unit, so that after the shaping processing is completed in the first control unit, the synthesized baseband data is sent to the baseband processing module; The processor is used to implement the correction algorithm, DOA estimation, shaping vector generation and configuration of the transceiver, and the first control unit sends the processed array data to the processor in real time, thereby completing the correction and DOA estimation; The second control unit is used for interface expansion, thereby controlling multiple TR components to complete the shaping and correction process; The first control unit includes a GTX interface, a sending shaping module, a receiving shaping module, a correction top-level module, a sending interface, a receiving interface, a sending shaping vector update module, a receiving shaping vector update module, a DOA data extraction module, a DSP interface module, an SRIO interface module, a TR control GTX interface module, a servo control interface module and an initial scanning module, wherein: For the GTX interface, data is exchanged with the baseband processing module to transmit baseband data, including modulated baseband data sent and unmodulated baseband data received; the interface is also used to transmit the content of the baseband processing module to the radio remote module, including control signals and clock synchronization signals; For the sending shaping module, the current frame shaping vector from the processor is first combined with the correction vector from the correction top module, and then the combined weighted vector is subjected to shaping operation with the baseband data from the baseband processing module, thereby obtaining the array element data; For the receiving shaping module, the array data and the corrected shaping vector are multiplied and self-added to combine the received shaping baseband data; The correction top-level module is used to implement the correction process, receives the correction control instruction from the baseband processing module, starts the correction process, sends the pre-stored correction waveform on each array element, uses the signal received by the adjacent array element to perform amplitude and phase correction between the array elements, and outputs the correction result in the form of a correction vector; For the transmission interface module, the array element signal is formatted and output according to the required data format, directly connected to the transceiver and the data packet is output in the form of LVDS level; For the sending shaping vector update module, the sending shaping vector is updated according to the correction and DOA results; For the receiving beamforming vector update module, the receiving beamforming vector is updated according to the correction and DOA results; The receiving interface module is directly connected to the transceiver, receives the data packets in the receiving direction of the transceiver in the form of LVDS level, and converts the data transmission format of the transceiver into the usual I / Q data format; The DOA data extraction module is used to extract the data used to calculate the DOA from the data stream and output it one by one according to the agreed method; For the DSP interface module, it schedules various types of data between the processor and implements bus arbitration through the same SRIO bus, and serves as a summary interface for various modules that interact with the processor; The SRIO interface module is used to exchange data with the processor; For TR control GTX interface module, it is used to expand and instantiate the control interface of TR; For the servo control interface, it controls the external turntable servo system and receives control instructions from the processor to cooperate in completing the system functions of initial scanning and tracking; For the initial scanning module, the initial scanning work after power-on is completed by controlling the turntable, and the turntable is positioned according to the scanning results to roughly capture the position and direction of the aerial node.

2. The mechanical servo digital phased array system according to claim 1, characterized in that: Perform AGC automatic gain control, where: AGC is completed through a 100us preamble signal at the beginning of each frame. The 100us preamble consists of 10us channel silence and 90us repeated detection sequence. The AGC control state machine has two states, namely the adjustment state and the locking state. In the adjustment state, the AGC performs open-loop dynamic adjustment according to the received spatial signal strength; in the locked state, the AGC no longer adjusts and all controllable gains are locked; the AGC is in the adjustment state before the signal arrives, and when the repeated detection sequence after the silence is received, the AGC adjustment is performed; when the system completes the signal arrival detection, that is, after the correlation operation confirms the peak value, the AGC enters the locking state, and when a frame is received, the AGC returns to the adjustment state.

3. The mechanical servo digital phased array system according to claim 2, characterized in that: For AGC automatic gain control, the switching conditions between the two states are: Locking state entry conditions: signal arrival detection confirmation; Conditions for entering the adjustment state: frame duration counting is completed; For the adjustment state, when the AGC module is in the adjustment state, the adjustment mechanism is always working. There are 3 detection points in the AGC module, which are located at the RF, IF and baseband respectively. The RF and IF detection points are located in the TR component, and are output through analog RSSI signals and enter the first control unit after passing through AD. The baseband detection point is located in the first control unit; there are also 3 control points in the AGC module, which are located before the 3 detection points, namely RF, IF and baseband. The RF and IF control points are located in the TR component, and a 30dB digitally controlled attenuator with an accuracy of 1dB is used. The baseband control point is in the transceiver, and the 3 control points are adjusted according to the strength of the signals at their corresponding detection points. For the locked state, the locked state is entered in a certain order. First, the intermediate frequency gain is immediately locked, then the radio frequency gain is locked, then the baseband gain is locked after T1+T2, and finally the baseband gain is locked after T3+T4. The locking process is as follows: After the signal arrival detection is confirmed, first release the intermediate frequency and radio frequency attenuators. After the control takes effect, detect RSSI, take the average of the detection results, and configure the attenuator according to the detection results. If both levels of RSSI are saturated in the first detection result, both levels of attenuators are fully attenuated. After the control takes effect, re-detect RSSI and take the average again. Adjust the radio frequency attenuation according to the second RSSI detection result. After the control takes effect, lock the baseband gain.

4. The mechanical servo digital phased array system according to claim 3, characterized in that: Carry out electromechanical joint control, which is specifically implemented as follows: A. The pitch angle is fixed, and the motor drives the azimuth angle to 0°; B. The azimuth angle is scanned from the 1st to the 24th level in sequence; C. Determine the initial direction of the incoming wave based on the received signal energy; D. Mechanically adjust the antenna array to the target position for data communication; E. If the communication quality is lower than a preset threshold, use the received signal to estimate the angle of arrival; F. Based on the obtained results, the specified angle beamforming is completed by controlling the phase of the analog-digital hybrid antenna array; G. Carry out data communication.

5. The mechanical servo digital phased array system according to claim 4, characterized in that: Perform step tracking. When the DOA algorithm obtains the accurate angle of the incoming wave, the mechanical pointing of the antenna array needs to be adjusted. The RF remote module uses each receiving time slot to perform DOA. According to the DOA result, the angle of the turntable servo system is adjusted in real time to complete the real-time tracking of the antenna beam in the horizontal direction. In the pitch direction, beamforming is performed according to the DOA result to ensure that the beam always points to the direction of the aerial node.

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