Fast continuous beam control method based on multi-channel phased-array antenna

Abstract

The invention discloses a fast continuous beam control method based on a multi-channel phased-array antenna, which relates to the technical field of phased-array antenna beam control, and comprises the following steps: receiving a beam control instruction, calculating the theoretical amplitude and phase of each vector synthesizer channel, and compensating and weighting the theoretical amplitude and phase of the channel to obtain the final amplitude and phase of the channel; the number M of required FLASH is calculated, and the calculated final amplitude phases of all channels are sequentially and circularly stored in the first FLASH, the second FLASH to the Mth FLASH in an assembly line mode; ping-pong operation is adopted to read original voltage data of all channels, and in the FLASH reading process, beam control data is distributed according to an assembly line mode; according to the invention, the phased-array antenna gets rid of the limitation of mutual influence of a control time sequence and a communication time sequence, and beam switching can be continuously and rapidly carried out.

Description

Technical Field

[0001] The present invention relates to the technical field of phased array antenna wave control, and particularly relates to a fast continuous beam control method based on a multi-channel phased array antenna. Background Art

[0002] Recently, due to characteristics such as high beam pointing accuracy and fast beam forming speed, phased array antennas have been widely used in fields such as radar and communication. To improve the beam pointing accuracy of phased array antennas, phased array antennas generally achieve this by increasing the number N of linear array elements, that is, by choosing a multi-channel design, and the number of channels can reach several hundred or even several thousand array elements. Also, because the signal processing system often has limitations on the coherent processing time (CPI), it is required that the phased array antenna complete beam configuration within dozens of microseconds or even a few microseconds. Therefore, there are clear requirements for the beam control time of phased array antennas.

[0003] First, the industry generally uses the method of matching a DA chip with a vector synthesizer for beam configuration. The control process of the vector synthesizer is divided into the following steps: receiving a beam control instruction and performing channel theoretical amplitude-phase calculation; compensating and weighting the channel theoretical amplitude-phase to obtain the final channel amplitude-phase; looking up the quantization voltage data according to the final channel amplitude-phase; and sending the quantization voltage data to the DA chip, thereby completing the channel amplitude-phase control of the vector synthesizer. The more channels there are, the longer it takes for the vector synthesizer to complete the channel amplitude-phase control. And due to channel differences, in order to ensure sufficient phase amplitude control accuracy for each channel, the quantization voltage data is huge, and it is usually difficult for high-speed reading chips such as DDR3 / DDR4 to store such a large amount of data. Therefore, the FLASH reading time has become the most direct factor affecting the beam control time. Second, when a DSP is used as the main control chip at the signal processor end, the beam control instruction sent and the beam update signal will be asynchronous, which will make it difficult to ensure the accuracy of the calculated beam control time advance. Finally, at present, in order to achieve multi-channel control of phased array antennas, most use a distributed control method, decomposing the entire antenna array into multiple sub-arrays (usually dozens of sub-arrays or modules), and using a parameterized pipeline design for channel amplitude-phase control, which to a certain extent solves the problem of long channel amplitude-phase control time for multi-channel antennas. However, because distributed calculation requires independent microprocessors (including but not limited to FPGA, DSP) and data storage devices to be configured for each sub-array, it has increased huge costs at the present stage.

[0004] Beam control commands are often sent in serial port mode, ranging from a dozen bytes to dozens or hundreds of bytes, and the communication rate is generally not higher than 40 Mbps. Therefore, the communication takes dozens of microseconds. During these dozens of microseconds, the phased array antenna end cannot re-complete the beam configuration, severely restricting the flexibility of the radar system. Additionally, for high PRF radar systems, the configuration time of dozens of microseconds is also unacceptable. If we want to achieve multi-beam continuous beam control, we must change the beam configuration method. With the process of device localization, the cost of more and more devices has doubled. The past practice of trading resources for time can no longer meet the existing needs, and distributed beam control has encountered great resistance. Summary of the Invention

[0005] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a fast continuous beam control method based on a multi-channel phased array antenna.

[0006] The purpose of the present invention is achieved through the following technical solutions: A fast continuous beam control method based on a multi-channel phased array antenna, including: Receiving a beam control command, calculating the theoretical amplitude and phase of each vector synthesizer channel, compensating and weighting the channel theoretical amplitude and phase to obtain the final channel amplitude and phase; Calculating the required number of FLASHs M, and sequentially storing all the calculated final channel amplitude and phase in a pipelined manner into the 1st, 2nd, to the Mth FLASH; Using ping-pong operation to read the original voltage data of all channels, and during the FLASH reading process, distributing the beam control data in a pipelined manner; The step of using ping-pong operation to read the original voltage data of all channels includes: After receiving the beam control command, starting to read the 1st, 2nd, to the Mth FLASH every other microprocessor driving clock cycle t in sequence; after M*t time, the first group of FLASH data reading is completed, and after every t time later, M groups of FLASH are sequentially read and completed, and the cycle continues until all the original voltage data of all channels is read.

[0007] Further, the number of FLASHs M is the ceiling value of the quotient of the FLASH chip reading time and the microprocessor driving clock cycle.

[0008] Further, it also includes: After completing multiple beam configurations within a communication cycle, identifying the beam number through the effective level length of the beam update signal, and performing beam free switching according to the identified beam number.

[0009] Further, the effective level of the beam update signal is active low, active high, or active with a special waveform, and the special waveform is generated by encoding through the mechanism of an asynchronous serial port.

[0010] Further, the identification of the beam number by the effective level length of the beam update signal includes: Dividing the range [a, b] of the effective level of the beam update signal into p intervals on average, where p is the number of beams; Identifying the beam with the effective level range of [a, a + (b - a) / p] as beam 1, [a + (b - a) / p, a + 2(b - a) / p] as beam 2, and so on to identify beam p.

[0011] Further, the multi-channel phased array antenna uses a centralized beam controller for beam control.

[0012] The beneficial effects of the present invention are: 1) The present invention makes adaptive modifications to the existing signal processing flow, enabling the phased array antenna to get rid of the limitation of the mutual influence between the control timing and the communication timing, and capable of continuously and quickly performing beam switching.

[0013] 2) Combining with the existing test conditions of the phased array antenna, the present invention can realize multi-direction and multi-frequency point tests of the phased array antenna, greatly improving the test and debugging efficiency of the phased array antenna.

[0014] 3) The present invention uses centralized beam control, which can not only improve the resource utilization rate, ensure the consistency of array surface control, but also greatly reduce the cost. Compared with the distributed beam control method, it can better meet the needs of current engineering applications. Description of the Drawings

[0015] Figure 1 It is a schematic diagram of ping-pong operation reading provided by an embodiment of the present invention; Figure 2 It is a signal schematic diagram when realizing beam identification and free switching provided by an embodiment of the present invention; Figure 3 It is a beam update signal diagram provided by an embodiment of the present invention. Detailed Embodiments

[0016] Next, the technical solutions of the present invention will be clearly and completely described in conjunction with the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts fall within the protection scope of the present invention.

[0017] Refer to Figures 1 - 3, the present invention provides a technical solution: Embodiment

[0018] A fast continuous beam control method based on a multi-channel phased array antenna, comprising: Step 1, receive a beam control instruction, calculate the theoretical amplitude and phase of each vector synthesizer channel, compensate and weight the channel theoretical amplitude and phase to obtain the final channel amplitude and phase; the final channel amplitude and phase data, that is, the attenuation value and phase shift value of each channel.

[0019] Step 2, calculate the required number of FLASHs M, and sequentially store all the calculated final channel amplitudes and phases in the first, second, to the Mth FLASHs in a pipelined manner; Further, the number of FLASHs M is the ceiling value of the quotient of the FLASH chip read time and the microprocessor driving clock cycle. The number of groups for ping-pong operation should match the FLASH chip read time and the microprocessor driving clock.

[0020] Step 3, read the original voltage data of all channels using ping-pong operation, and during the FLASH reading process, distribute the beam control data in a pipelined manner.

[0021] Among them, the original voltage data is converted from the stored attenuation value and phase shift value by means of a look-up table. The principle is: address coding is performed according to the attenuation value and phase shift value. For example, there are 180 phase shift values with a step of 2°, and 32 attenuation values with a step of 0.5 dB. If the attenuation of a certain channel is 2 dB and the phase shift value is 10°, then the address to be fetched is: (10 / 2)+180*(2 / 0.5)=725, and the original voltage value corresponding to the amplitude and phase is stored at this address.

[0022] The reading of the original voltage data of all channels using ping-pong operation is as Figure 1 shown, where AddrMUX is an address selection module, connected to the interface of the external storage chip. This module will send the storage chip addresses to multiple groups of external storage chips respectively according to the preset number of channel groups, so that the entire data reading process meets the pipelining requirements; FLASH1, FLASH2, FLASH3, FLASH4 are a group of external storage chips. After receiving the addresses from the address selection module, the external storage chips retrieve the data corresponding to the addresses and send them to the data integration module. Among them, in addition to the basic channel amplitude and phase information, the data may also include the power-on and attenuation information of the channels. DataMUX is a data integration module. This module caches the data sent by the external storage chips and sends the corresponding channel data according to the channel number of the beam control module. Specifically including: After receiving the beam control instruction, start reading the 1st, 2nd, to the Mth FLASH at intervals of one microprocessor drive clock cycle t in sequence; after M*t time, the first group of FLASH data is read out, and then every t time, M groups of FLASH are read out in sequence, and the cycle continues until all the original voltage data of all channels is read out.

[0023] In a specific embodiment, the reading time of the FLASH chip is 95 ns, the microprocessor drive clock cycle is 25 ns, and the number of required FLASHs M is determined to be 4. 4 times the drive clock cycle is slightly greater than the reading time of the FLASH chip, which can meet the requirements of system stability and redundancy. Further, taking the phased array antenna element number N = 1152 and the microprocessor clock 40 MHz (the microprocessor drive clock cycle is 25 ns) as an example, all channels are divided into four groups in sequence (i.e., 1, 5, 9... 1149 is a group, 2, 6, 10... 1150 is a group, 3, 7, 11... 1151 is a group, 4, 8, 12... 1152 is a group), with 288 channels in each group, and are respectively stored in four groups of FLASHs.

[0024] After calculating the final amplitude and phase in a pipelined manner, read the four groups of FLASHs at intervals of 25 ns (corresponding to one 40 MHz clock cycle). After 100 ns, the first group of FLASH data is read out, and then every 25 ns, the four groups of FLASHs are read out in sequence, and the cycle continues until all the original voltage data of all channels is read out. That is, during the FLASH reading process, the beam control data can still be read and allocated in a pipelined manner, greatly improving the system signal processing efficiency.

[0025] Use ping-pong operation to complete high-speed data reading and use a special beam update signal to complete multi-beam switching. This solution enables the phased array antenna in multi-channel control to reduce the beam control time and greatly improve the beam control flexibility of the phased array antenna, and completes the continuous beam control of the multi-channel phased array antenna. Embodiment

[0026] Based on the above Embodiment 1, a fast continuous beam control method based on a multi-channel phased array antenna further includes: As Figure 2 shown, after completing multiple beam configurations within a communication cycle, identify the beam number through the effective level length of the beam update signal, and perform beam free switching according to the identified beam number without having to wait to read data again.

[0027] Specifically, the identifying the beam number through the effective level length of the beam update signal includes: Dividing the range [a, b] of the effective level of the beam update signal into p intervals on average, where p is the number of beams; Beams with an effective level range of [a, a + (b - a) / p] are identified as beam 1, beams with an effective level range of [a + (b - a) / p, a + 2(b - a) / p] are identified as beam 2, and so on, until beam p is identified.

[0028] Optionally, the effective level of the beam update signal is active low, active high, or active with a special waveform. The beam update signal is generally a pulse synchronization signal generated by the signal processor, and its function is to control the phased array antenna to complete beam synchronization update. Due to the synchronization requirements of the entire system, it is often required that the pulse width is less than 1 us. Therefore, the mechanism of an asynchronous serial port can be emulated for encoding to generate a special waveform. Taking active high as an example, if 0.1 us is defined as 1 bit, then the 1 us time can be evenly divided into 10 bits. Among them, the first bit is the trigger bit (high level), followed by 8 encoding bits, and finally the last bit is the end bit (high level). The corresponding encoding for each beam is shown in Table 1, achieving the switching of preset beams within 1 us. Compared with conventional low-level triggering or high-level triggering, this method not only meets the system synchronization requirements but also can effectively achieve fast switching between multiple beams. To ensure time ambiguity between systems, the above encoding can adopt encoding methods such as one-hot code and Gray code, which have no essential difference from the above encoding method. The beam update signal diagram is as Figure 3 shown.

[0029] Table 1: Corresponding encoding table for each beam Beam type Pulse coding Beam 1 0x01 Beam 2 0x02 …… …… Beam 255 0xFF By increasing the number of pins of the beam update signal, setting the active time of high and low levels or special waveforms, multi-beam switching is completed. There is no need to continuously send beam control commands in the middle. On the one hand, it saves the communication time required, and on the other hand, beam cycle control or frequency fast switching can be performed according to needs, greatly improving the system working efficiency. Embodiment

[0030] Based on the above Embodiment 1 or 2, a fast continuous beam control method based on a multi-channel phased array antenna further includes: the multi-channel phased array antenna uses a centralized beam controller for beam control.

[0031] Centralized beam control can not only improve resource utilization rate, ensure the consistency of array surface control, but also greatly reduce costs. Compared with the distributed beam control method, it can better meet the needs of current engineering applications.

[0032] The above are only the preferred embodiments of the present invention. It should be understood that the present invention is not limited to the forms disclosed herein, and should not be regarded as excluding other embodiments. Instead, it can be used in various other combinations, modifications, and environments, and can be changed within the scope of the concept described herein through the above teachings or the techniques or knowledge in the relevant field. Any changes and variations made by those skilled in the art without departing from the spirit and scope of the present invention shall fall within the protection scope of the appended claims of the present invention.

Claims

1. A fast continuous beam control method based on a multi-channel phased array antenna, characterized in that: Including: Receiving a beam control instruction, calculating the theoretical amplitude and phase of each vector synthesizer channel, compensating and weighting the channel theoretical amplitude and phase to obtain the final channel amplitude and phase; Calculating the required number of FLASHs M, and sequentially storing all the calculated final channel amplitude and phase into the 1st, 2nd, up to the Mth FLASH in a pipelined manner; Reading the original voltage data of all channels using ping-pong operation, and distributing the beam control data in a pipelined manner during the FLASH reading process; The reading of the original voltage data of all channels using ping-pong operation includes: Starting from when the beam control instruction is received, sequentially reading the 1st, 2nd, up to the Mth FLASH every other microprocessor drive clock cycle t; After M*t time, the first group of FLASH data reading is completed, and every M groups of FLASH are sequentially read after every t time, cycling until all the original voltage data of all channels are read.

2. The fast continuous beam control method based on a multi-channel phased array antenna according to claim 1, characterized in that: The number of FLASHs M is the ceiling value of the quotient of the FLASH chip reading time and the microprocessor drive clock cycle.

3. A fast continuous beam control method based on a multi-channel phased array antenna according to claim 1, characterized in that: Also including: After completing multiple beam configurations within one communication cycle, identifying the beam number through the effective level length of the beam update signal, and performing beam free switching according to the identified beam number.

4. A fast continuous beam control method based on a multi-channel phased array antenna according to claim 3, characterized in that: The effective level of the beam update signal is active low, active high or a special waveform is active, and the special waveform is a waveform generated by encoding through the mechanism of an asynchronous serial port.

5. A fast continuous beam control method based on a multi-channel phased array antenna according to claim 3, characterized in that: The identifying the beam number through the effective level length of the beam update signal includes: Dividing the range [a, b] of the effective level of the beam update signal into p intervals on average, where p is the number of beams; Identifying the beam with the effective level range of [a, a+(b - a) / p] as beam 1, [a+(b - a) / p, a+2(b - a) / p] as beam 2, and so on to identify beam p.

6. A fast continuous beam control method based on a multi-channel phased array antenna according to claim 1, characterized in that: The multi-channel phased array antenna uses a centralized beam controller for beam control.

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