A multi-stage adaptive signal receiving method with large dynamic range

Abstract

The present invention discloses a multi-stage adaptive signal reception method with large dynamic range, belonging to the field of electronic countermeasures. First, a multi-stage gain fusion unit with two routing switch selections is constructed, each including an N-stage coupled cascade amplification channel and an M-stage coupled cascade attenuation channel. Next, based on the signal amplitude information uploaded by the detector, the signal input is determined to be in the N-stage amplification channel or the M-stage attenuation channel, and the required output gain or attenuation is calculated based on the signal amplitude. Next, the noise coefficient and cascade propagation loss of the signal channel are calculated. Finally, an intelligent feedback network is used to determine the actual operating attenuation coefficient. Finally, the multi-stage gain fusion network adaptively feeds back the gain multiplier, i.e., reversely controlling the gain and matching the output level.

Description

Technical Field

[0001] The invention belongs to the field of electronic countermeasures, and in particular relates to a multi-order adaptive large dynamic signal receiving method. Background Art

[0002] With the advancement of modern electronic warfare technology, the receiving systems of electronic countermeasures equipment are becoming more sensitive, with superior frequency and bandwidth performance. Broadband RF channels typically contain signals of many different frequencies, and to achieve the greatest possible interference distance and adapt to increasingly complex electromagnetic operating environments, radar signals of varying strengths must be received as effectively as possible by the countermeasures system. Especially for millimeter-wave countermeasures systems operating over wide bandwidths, a wider dynamic range enhances the equipment's environmental adaptability. Therefore, large-dynamic reception technology is currently a key research topic.

[0003] Currently, achieving a wide dynamic range at the receiving end of radar systems primarily involves reducing system sensitivity, minimizing ambient noise, and enhancing the signal strength of the receiver's front-end processing. However, while ensuring proper operation of the equipment, improving the materials and performance of electronic components is limited, and this approach makes improving sensitivity increasingly difficult. Alternatively, efforts can be made to maximize signal reception, particularly in electronic countermeasures. This approach can accommodate more complex noise environments and mitigate the impact of channel saturation on the RF processing backend. However, this approach offers a relatively limited approach to raising the upper limit of the received level. Furthermore, maintaining a normal operating noise figure range and gain flatness are essential considerations in designing systems with a wide dynamic range. In practical engineering practice, these multiple factors must be comprehensively considered to develop feasible solutions. Summary of the Invention

[0004] The present invention proposes a multi-stage adaptive large dynamic signal receiving method. For high-frequency signals and large bandwidth conditions, traditional large dynamic receiving methods are single, have limited performance, and cannot adaptively ensure the stability of large dynamic reception.

[0005] The technical solution to realize the present invention is: a multi-stage adaptive signal large dynamic reception method, comprising the following steps:

[0006] Step 1: Construct a coupled cascade amplification channel and a coupled cascade attenuation channel to form a multi-stage gain fusion unit.

[0007] Step 2: Based on the amplitude information of the signal uploaded by the detector and compared with the amplitude control threshold, the amplification channel or the attenuation channel is selected in the multi-stage fusion gain unit.

[0008] Step 3: Increase the number of gain stages, and perform real-time calculations through adaptive gain feedback. Calculate the output level after the gain of this stage based on the signal amplitude to see if it meets the intermediate frequency processing requirements.

[0009] Step 4: Calculate the noise coefficient of the signal channel and perform adaptive channel control to ensure signal quality.

[0010] Step 5: Calculate the cascade propagation loss and adaptively ensure the flatness of broadband signal transmission.

[0011] Step 6: Track and feedback the gain in real time through the intelligent feedback network, determine the gain level, and output the safe range level value.

[0012] Compared with the prior art, the present invention has the following significant advantages:

[0013] (1) The principle of the present invention is simple and easy to implement. The signal amplitude that meets the intermediate frequency processing requirements can be output through the gain feedback mechanism. The detector measures the amplitude at a fast rate, with high accuracy and good output stability. The signal gain can be adaptively controlled through the feedback network.

[0014] (2) According to the frequency and bandwidth characteristics of the detection signal, the typical center frequency of the back-end digital signal processing is intelligently matched to fully receive the signal level range in the environment, while ensuring the flatness and noise coefficient of the receiving front-end signal transmission, thereby increasing the signal-to-noise ratio in the channel and improving the receiving dynamic range. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a flow chart of a multi-stage adaptive signal large dynamic reception method of the present invention.

[0016] Figure 2 This is a working block diagram of a multi-stage adaptive signal large dynamic receiving method of the present invention.

[0017] Figure 3 Schematic diagram of the large dynamic signal receiving bandwidth. DETAILED DESCRIPTION

[0018] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. 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.

[0019] The following will further introduce the specific implementation methods, as well as the technical difficulties and inventive points of this invention in combination with this design example.

[0020] The present invention provides a method based on gain cascade coupling and parallel attenuation fusion to bidirectionally improve the dynamic range of the system receiving front end, thereby improving the sensitivity of electronic countermeasures when reception is difficult in complex environments and receiving as large signals as possible, adaptively feedback the gain channel transmission situation, avoid the influence of channel saturation on the radio frequency processing back end, and realize the large dynamic reception function of the front-end signal.

[0021] Combine Figure 1 and Figure 2 A multi-stage adaptive signal large dynamic reception method of the present invention comprises the following steps:

[0022] Step 1: Construct a total of N-stage coupled cascade amplification channel and an M-stage coupled cascade attenuation channel to form a multi-stage gain fusion unit. Among them, the gain of the first N-stage coupled cascade amplification channel is XH N , the attenuation channel gain of the first M-stage coupling cascade is XL M , where M and N can be set according to actual index requirements and device performance.

[0023] Step 2: The detector uploads the signal amplitude A c , compared with the proposed intermediate frequency level value A0, the multi-stage fusion gain unit adaptively selects the amplification channel or the attenuation channel. A0 is the typical level amplitude of the signal intermediate frequency processing.

[0024] Step 3: Increase the gain level according to the signal amplitude A uploaded by the detector. c Calculate the output level after the gain of this stage in real time to determine whether it meets the intermediate frequency processing requirements, as follows:

[0025] Calculate the level value A after the i-th level gain i :

[0026] A i =G1×G2×…×G i ×A c

[0027] ΔA i =A i -A0

[0028] Among them, G i Represents the gain of the i-th stage.

[0029] Judgment A i The difference ΔA from the amplitude control threshold A0 i Is it greater than the voltage receiving range ΔA0? If so, adjust to the next level of gain in real time through adaptive gain feedback. Let i = i + 1 and calculate the corresponding level value A after gain at this time. i .

[0030] Step 4: Calculate the noise coefficient of the signal channel of the first i-level gain according to the formula to determine whether it meets the reference noise threshold NF A If the requirements are met, go to the next step to calculate the propagation loss; otherwise, select the level that meets the requirements according to the noise coefficient requirements. The noise coefficient is generally controlled within a certain range, thereby controlling the signal transmission quality.

[0031] In step 4, calculate the total output noise figure NF of the signal channel of the first i-stage gain O , real-time tracking of the channel's anti-blocking capability, thereby achieving stability in large dynamic channel reception. The calculation process is as follows:

[0032]

[0033] Among them, NF i represents the noise figure of the i-th stage.

[0034] Determine whether NF0 meets the reference noise threshold NF A If the requirements are met, go to the next step to calculate the propagation loss; otherwise, select the level that meets the requirements according to the noise coefficient requirements. The noise coefficient is generally controlled within a certain range, thereby controlling the signal transmission quality.

[0035] Step 5: Calculate the propagation loss and determine whether the propagation loss meets the circuit's predetermined index L. A If satisfied, go to step 3 and continue to adjust the gain level through adaptive gain feedback; otherwise, go to the next step;

[0036] L i =10lg[1-(μ i ×ΔA i ) 2 ]

[0037] where μ i =Voltage reflection coefficient. When the number of gain stages reaches a certain value, the channel can easily generate a large standing wave ratio (SWR), necessitating isolation between gain devices. Propagation loss is used as a criterion to ensure the flatness of broadband signal transmission, thereby guaranteeing high dynamic reception capability within the signal channel of electronic countermeasure equipment. The propagation loss of each stage is generally related to the reflection coefficient of the device at that stage, and the allowable propagation loss range can be set based on actual requirements.

[0038] Step 6: Real-time tracking and feedback of the current gain, determination of the gain level, and output of the safe range level value, as follows:

[0039] The multi-stage gain fusion unit determines the gain level i. If the attenuation channel is selected, i≤M; if the amplification channel is selected, i≤N. Generally, the gain of a single stage is G iThe maximum adjustable range is approximately 40dB, ensuring that the gain circuit operates in the linear region as much as possible to prevent oversaturation, which would affect device reliability.

[0040] Extracted feedback gain G = G1 × G2 × … × G i After receiving the front-end signal and passing through the multi-stage gain fusion unit gain, the comprehensive matching outputs the safety range level value A to the back-end, A=A i .

[0041] Example:

[0042] The present invention provides a multi-stage adaptive signal large dynamic reception method, the method steps are as follows:

[0043] Figure 3 This is a schematic diagram of the large dynamic signal receiving bandwidth. It constructs a 4-stage coupled cascade amplification channel and a 4-stage coupled cascade attenuation channel. The gain of each stage can be adjusted to 20dB, forming a multi-stage gain fusion unit.

[0044] During the test, IF bandwidths of 10MHz, 20MHz, and 30MHz were set, and signals of varying amplitudes were input to the receiving front end at different IF bandwidths, as shown below. The detector detected each signal amplitude and compared it with the IF level A0 to select the corresponding gain channel. The typical IF processing level A0 was set to -20dBm, and these levels were converted to power values for calculation.

[0045]

[0046]

[0047] Experimental results demonstrate that for broadband signals of varying frequencies and powers, the multi-stage fusion gain unit adaptively adjusts the gain accordingly, effectively compensating for the energy entering the intermediate frequency signal processing. With increasing gain levels, especially when selecting an attenuation channel, normal operation can guarantee 120dB of attenuation, depending on the performance requirements and the selected components. This method mitigates the risk of large signals posing a risk to the full load of the components. Under low-energy signal conditions, the coupled cascade amplifier's output signal power amplitude fluctuates significantly from the set value due to high broadband noise. The system balances gain and channel noise, thereby achieving dynamic range and electronic component reliability management.

[0048] The multi-stage adaptive signal reception method proposed in this invention can fully broaden the received power range based on adaptive gain calculation feedback and bidirectional feedback from a multi-stage gain fusion unit. Simultaneously, by tracking in-band propagation loss and noise power, it effectively controls the channel's transmission quality and improves the dynamic range and stability of the receiving front end. In summary, this invention can broaden the signal reception amplitude range for high-frequency, wide-bandwidth signals, meeting the demand for large-dynamic signal reception in the field of electronic countermeasures and possessing broad application value.

Claims

1. A multi-stage adaptive signal large dynamic reception method, characterized in that: The following steps are involved: Step 1: Construct a multi-stage gain fusion unit. The multi-stage gain fusion unit is composed of an N-stage coupled cascade amplification channel and an M-stage coupled cascade attenuation channel in parallel. The amplification gain of the N-stage coupled cascade amplification channel is , the attenuation gain of the M-level coupled cascade attenuation channel is , go to step 2; Step 2: Detector uploads signal amplitude ,Will Amplitude control threshold Compare, and select the amplification channel or attenuation channel in the multi-stage fusion gain unit according to the comparison result, and go to step 3; Step 3: Increase the gain level according to the signal amplitude Calculate the output level after adding the gain stages in real time to determine whether it meets the intermediate frequency processing requirements. If so, proceed to step 4. Step 4: Calculate the noise figure of the signal channel ,judge Whether the reference noise threshold is met If the requirements are met, go to step 5; otherwise, select the required number of stages according to the noise coefficient requirements; Step 5: Calculate the current cascade propagation loss ,judge Whether the circuit meets the predetermined indicators If satisfied, go to step 3 and continue to adjust the gain level; otherwise, go to step 6; Step 6: Real-time tracking and feedback of the current gain, determination of the gain level, and output of the safe range level value.

2. The multi-stage adaptive signal large dynamic reception method according to claim 1, characterized in that: In step 2, the amplitude control threshold is the proposed intermediate frequency level value.

3. The multi-stage adaptive signal large dynamic reception method according to claim 2, characterized in that: In step 3, increase the gain level according to the amplitude of the signal uploaded by the detector The output level value after increasing the gain stage is calculated in real time to determine whether it meets the intermediate frequency processing requirements, as follows: Calculate the Level value after stage gain : ； ， in, Indicates the The gain of the stage; judge Amplitude control threshold The difference Is it greater than the voltage receiving range? If yes, the next level gain is calculated in real time through adaptive gain feedback, so Calculate the corresponding level value after gain at this time .

4. The multi-stage adaptive signal large dynamic reception method according to claim 3, characterized in that: In step 4, the noise figure of the signal channel is calculated and the signal quality is guaranteed by channel adaptive control, as follows: Before calculation The total output noise figure of the signal path with the first-level gain : ， in, Indicates the Noise figure of the stage; judge Whether the reference noise threshold is met If the requirements are met, go to the next step to calculate the propagation loss; otherwise, select the required level according to the noise coefficient requirements, and control the noise coefficient within a certain range, thereby controlling the signal transmission quality.

5. The multi-stage adaptive signal large dynamic reception method according to claim 4, characterized in that: In step 5, calculate the propagation loss : ， in is the voltage reflection coefficient.

6. The multi-stage adaptive signal large dynamic reception method according to claim 5, characterized in that: In step 6, the current gain is tracked and fed back in real time, the gain level is determined, and the safe range level value is output, as follows: Multi-stage gain fusion unit determines the number of gain stages If the attenuation channel is selected, then ; If the amplified channel is selected, Extract feedback gain, receive the front-end signal and pass it through the multi-stage gain fusion unit gain, and then output the safe range level value to the back-end through comprehensive matching. , .

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