A TDM-MIMO radar velocity measurement extension method based on array characteristics and track information

Abstract

The embodiment of the application discloses a TDM-MIMO radar velocity measurement expansion method based on array characteristics and track information, which comprises the following steps: obtaining possible virtual array Doppler phase offset compensation by assuming target motion direction; performing FFT processing on the compensated virtual array signal to obtain an angle spectrum; utilizing the correlation between the angle spectrum and the ambiguous velocity to obtain two kinds of different direction unambiguous velocities; combining the track information to determine which kind of unambiguous velocity is true, so as to realize velocity measurement range expansion. The TDM-MIMO radar velocity measurement expansion method based on array characteristics and track information can further improve the TDM-MIMO radar velocity measurement range by combining array characteristics and tracking information. In addition, the method does not increase the calculation complexity. Compared with the method of expanding the velocity measurement range by only utilizing array characteristics, the method can greatly improve the TDM-MIMO radar velocity measurement range without increasing the calculation amount, and has high engineering practical value in the fields of traffic and automobiles.

Description

Technical Field

[0001] This invention relates to the field of millimeter-wave radar technology, specifically to a TDM-MIMO radar velocity measurement extension method based on array characteristics and track information. Background Technology

[0002] Currently, millimeter-wave MIMO radar using TDM waveforms is widely used in the transportation and automotive fields. TDM-MIMO radar expands the array aperture to improve angle measurement performance by using time-division multiplexing of the transmitting antenna, but due to N... t With each transmitting antenna alternately transmitting signals, the unambiguous velocity measurement range will decrease to (1 / N) of its previous value. t An excessively low speed detection range would affect the application of radar in fields such as transportation and automobiles.

[0003] However, existing TDM-MIMO radars, using array angle estimation and phase offset compensation methods, can at most extend velocity measurement to [-λ / (4T] c ),λ / (4T c This speed measurement range will still limit the application scenarios of common millimeter-wave radars, such as T... c The 80GHz carrier frequency 4-transmit 4-receive TDM-MIMO radar with a speed of 26µs, which uses array characteristics to extend the speed measurement range to [-129.8km / h, 129.8km / h], still cannot meet the needs of applications in highway scenarios. Summary of the Invention

[0004] In view of this, the present invention provides a TDM-MIMO radar velocity measurement extension method based on array characteristics and track information.

[0005] The TDM-MIMO radar velocity measurement extension method based on array characteristics and track information mainly includes:

[0006] Possible virtual array Doppler phase offset compensation is obtained by assuming the target's motion direction; the angle spectrum is obtained by performing FFT processing on the compensated virtual array signal; the correlation between the angle spectrum and the fuzzy velocity is used to obtain two different unfuzzy velocities in different directions; and the trajectory information is combined to determine which unfuzzy velocity is true, thereby expanding the speed measurement range.

[0007] According to a preferred embodiment of the present invention, obtaining possible virtual array Doppler phase offset compensation by assuming the target motion direction includes:

[0008] The MIMO radar system transmits FMCW signals according to the TDM waveform, and the received echo signals are mixed by a mixer to obtain the beat signal.

[0009] At this point, the TDM-MIMO radar system determines the unambiguous velocity range as follows:

[0010]

[0011] Among them, V max The maximum unambiguous velocity that radar can measure, λ is the wavelength of the FMCW signal, and T c N represents the pulse interval between adjacent transmit antennas in the TDM waveform. t This refers to the number of transmitting antennas;

[0012] The sampled beat signal is processed by 2D-FFT to obtain the range-Doppler matrix;

[0013] CFAR is used to perform target detection on the range-Doppler matrix, and the target's range and Doppler index are obtained;

[0014] When the direction of the target's motion can be determined, the non-fuzzy velocity range becomes:

[0015] Assuming the target moves away from the radar,

[0016] Assuming the target approaches the radar,

[0017] Among them, V max2 V represents the maximum unambiguous velocity under the current assumptions. est The fuzzy velocity of the target under the current assumption;

[0018] By selecting an assumption about the target's motion direction, the blurred velocity V of the target under the current assumption is calculated using Doppler indexing. est ;

[0019] Based on the current assumptions, the target's ambiguous velocity V est Calculate N t Possible Doppler phase biases:

[0020] Assuming the target moves away from the radar

[0021] Assuming target approach radar

[0022] in, The Doppler phase bias is based on the current assumption.

[0023] Calculate the phase P of the virtual array signal S, assuming the MIMO radar system has N receiving antennas. r =4, let the angle of the moving target be θ, and the phase P of the virtual array signal S be:

[0024]

[0025] in, Induce a step phase for the target in the θ direction. V is the phase deflection caused by the target motion. r The true radial velocity of the target;

[0026] Apply N to the virtual array signal S t Phase is The compensation is obtained by virtual array Doppler phase offset compensation S c .

[0027] According to a preferred embodiment of the present invention, FFT processing is performed on the compensated virtual array signal to obtain the angular spectrum, including:

[0028] Doppler phase offset compensation for virtual array S c Perform FFT processing to obtain N t When the phase offset is correctly compensated, the spectral peak of the angle spectrum is the largest when the phase offset is lower.

[0029] The peak values ​​of these angle spectra are compared, and the phase offset compensation corresponding to the largest peak value is selected. As a candidate phase bias, the fuzzy multiplicity m i The candidate velocity fuzzy multiplicity is used, and the angle corresponding to this spectral peak is used as the angle estimate of the target.

[0030] According to a preferred embodiment of the present invention, by utilizing the correlation between the angle spectrum and the fuzzy velocity, two different unfuzzing velocities in different directions are obtained, including:

[0031] The defuzzification velocity of the target in two different directions is calculated using the fuzzy multiplicity mi:

[0032] V r+ =V est+ +m i+ ·V max2 Assuming the target moves away from the radar

[0033] V r- =V est- -m i- ·V max2 Assuming the target approaches the radar

[0034] V est+ -V est- =V max2 m i+ +m i- +1=N t

[0035] Among them, V r+ V is the unambiguous velocity of the target when it departs from the hypothesis. r- V is the unambiguous velocity of the target when approaching the hypothesis. est+ and mi+ V represents the fuzzy velocity and fuzzy multiplicity of the target when it departs from the assumption. est- and m i- The fuzzy velocity and fuzzy multiplicity of the target when approaching the assumption.

[0036] According to a preferred embodiment of the present invention, by combining track information and determining which unambiguous velocity is true, thereby expanding the velocity measurement range, the method includes:

[0037] The target's position information is calculated using the target's distance index and angle estimate, and then track association is performed.

[0038] According to a preferred embodiment of the present invention, the target position information is calculated using the target's distance index and angle estimation value, and track association is performed, including:

[0039] The unfuzzing velocities in two different directions are compared with the radial velocity direction of the associated track, and the unfuzzing velocity that is the same as the radial velocity direction of the track is selected as the final radial velocity V. r ;

[0040] Thus, the speed range of the TDM-MIMO radar is extended to:

[0041]

[0042] The TDM-MIMO radar velocity measurement extension method based on array characteristics and track information provided in this invention has at least one of the following technical effects:

[0043] The TDM-MIMO radar speed measurement extension method based on array characteristics and track information in this embodiment of the invention can further improve the speed measurement range of TDM-MIMO radar by combining array characteristics and tracking information. On the other hand, most TDM-MIMO radars used in the transportation and automotive fields will perform tracking filtering on the target after obtaining the target distance, speed and angle information. Using this method will not increase the computational complexity too much.

[0044] Compared to methods that only utilize array characteristics to extend the speed measurement range, the method proposed in this invention can further extend the speed measurement range. Moreover, this method can significantly improve the speed measurement range of TDM-MIMO radar without increasing the amount of computation, and has extremely high engineering practical value in the fields of transportation and automobiles.

[0045] Some additional features of the present invention will be described in the following description. These additional features will become apparent to those skilled in the art upon examination of the following description and the accompanying drawings, or upon understanding the production or operation of the embodiments. The features disclosed in this invention can be implemented and achieved through the practice or use of various methods, means, and combinations thereof with respect to the specific embodiments described below. Attached Figure Description

[0046] The accompanying drawings, which are provided to further illustrate the invention and constitute a part of this invention, illustrate exemplary embodiments of the invention and are used to explain the invention, but do not constitute a limitation thereof. In the drawings, the same reference numerals denote the same parts.

[0047] Figure 1 The FMCW waveform diagram of the TDM-MIMO radar;

[0048] Figure 2 This is a schematic diagram showing the positional relationship of the TDM-MIMO radar array;

[0049] Figure 3 This is a schematic diagram of a TDM-MIMO radar virtual array.

[0050] Figure 4 This is a schematic diagram of the possible angle spectrum after phase offset compensation for the departure and approach assumptions in Example 1;

[0051] Figure 5 The table shows the simulation results of velocity fuzziness resolution for the initial stage of the trajectories of four moving targets using the method of this invention.

[0052] Figure 6 This is a flowchart illustrating the TDM-MIMO radar velocity measurement extension method based on array characteristics and track information, as shown in an embodiment of the present invention. Detailed Implementation

[0053] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0054] It should be noted that when the terms "first," "second," etc., are used in the specification, claims, and accompanying drawings of this invention, they are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate for the embodiments of the invention described herein. Furthermore, when the terms "comprising" and "having," and any variations thereof, are used, it is intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0055] In this invention, when terms such as "upper," "lower," "left," "right," "front," "rear," "top," "bottom," "inner," "outer," "middle," "vertical," "horizontal," "lateral," and "longitudinal" are used, they indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for the purpose of better describing this invention and its embodiments, and are not intended to limit the indicated device, element, or component to having a specific orientation, or to be constructed and operated in a specific orientation.

[0056] Furthermore, in addition to indicating direction or positional relationship, some of the aforementioned terms may also have other meanings. For example, the term "above" may also be used in certain situations to indicate a dependency or connection. Those skilled in the art can understand the specific meaning of these terms in this invention based on the specific circumstances.

[0057] Furthermore, in this invention, the terms "installation," "setting," "equipped with," "connection," "linking," and "sleeving," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0058] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0059] This invention discloses a TDM-MIMO radar velocity measurement extension method based on array characteristics and track information.

[0060] like Figures 1 to 6 As shown, this TDM-MIMO radar velocity extension method based on array characteristics and track information mainly includes:

[0061] Possible virtual array Doppler phase offset compensation is obtained by assuming the target's motion direction;

[0062] The angle spectrum is obtained by performing FFT processing on the compensated virtual array signal;

[0063] By utilizing the correlation between the angular spectrum and the fuzzy velocity, two different fuzzy velocities in different directions are obtained;

[0064] By combining flight track information, it can determine which unambiguous velocity is true, thereby expanding the velocity measurement range.

[0065] Among these, obtaining possible virtual array Doppler phase offset compensation by assuming the target motion direction can include:

[0066] The MIMO radar system transmits FMCW signals according to the TDM waveform, and the received echo signals are mixed by a mixer to obtain the beat signal.

[0067] At this point, the TDM-MIMO radar system determines the unambiguous velocity range as follows:

[0068]

[0069] Among them, V max The maximum unambiguous velocity that radar can measure, λ is the wavelength of the FMCW signal, and T c N represents the pulse interval between adjacent transmit antennas in the TDM waveform. t This refers to the number of transmitting antennas;

[0070] The sampled beat signal is processed by 2D-FFT to obtain the range-Doppler matrix;

[0071] CFAR is used to perform target detection on the range-Doppler matrix, and the target's range and Doppler index are obtained;

[0072] When the direction of the target's motion can be determined, the unambiguous velocity range becomes (i.e., assuming that there are only targets moving away from or only targets approaching the radar in the scene, then the unambiguous velocity range becomes):

[0073] Assuming the target moves away from the radar,

[0074] Assuming the target approaches the radar,

[0075] Among them, V max2 V represents the maximum unambiguous velocity under the current assumptions. est The fuzzy velocity of the target under the current assumption;

[0076] By selecting an assumption about the target's motion direction, the blurred velocity V of the target under the current assumption is calculated using Doppler indexing.est ;

[0077] Based on the current assumptions, the target's ambiguous velocity V est Calculate N t Possible Doppler phase biases:

[0078] Assuming the target moves away from the radar

[0079] Assuming target approach radar

[0080] in, The Doppler phase bias is based on the current assumptions.

[0081] Calculate the phase P of the virtual array signal S. Assume the number of receiving antennas in the MIMO radar system is Nr = 4, and the moving target angle is θ. The phase P of the virtual array signal S is:

[0082]

[0083] in, Induce a step phase for the target in the θ direction. Vr represents the phase deflection caused by the target's motion, and Vr represents the target's true radial velocity.

[0084] Apply N to the virtual array signal S t Phase is The compensation is obtained by virtual array Doppler phase offset compensation S c .

[0085] The angle spectrum obtained by performing FFT processing on the compensated virtual array signal can include:

[0086] Doppler phase offset compensation for virtual array S c Perform FFT processing to obtain N t When the phase offset is correctly compensated, the spectral peak of the angle spectrum is the largest when the phase offset is lower.

[0087] The peak values ​​of these angle spectra are compared, and the phase offset compensation corresponding to the largest peak value is selected. As a candidate phase bias, the fuzzy multiplicity m i The candidate velocity fuzzy multiplicity is used, and the angle corresponding to this spectral peak is used as the angle estimate of the target.

[0088] Among them, by utilizing the correlation between the angle spectrum and the fuzzy velocity, two different unfuzzy velocities in different directions can be obtained, which may include:

[0089] Using fuzzy multiplicity m i Calculate the unambiguity resolution rate for the target in two different directions:

[0090] Vr+ =V est+ +m i+ ·V max2 Assuming the target moves away from the radar

[0091] V r- =V est- -m i- ·V max2 Assuming the target approaches the radar

[0092] V est+ -V est- =V max2 m i+ +m i- +1=N t

[0093] Among them, V r+ V is the unambiguous velocity of the target when it departs from the hypothesis. r- V is the unambiguous velocity of the target when approaching the hypothesis. est+ and m i+ V represents the fuzzy velocity and fuzzy multiplicity of the target when it departs from the assumption. est- and m i- The fuzzy velocity and fuzzy multiplicity of the target when approaching the assumption.

[0094] Among these, combining track information to determine which unambiguous velocity is true, thereby expanding the velocity measurement range, can include:

[0095] The target's position information is calculated using the target's distance index and angle estimate, and then track association is performed.

[0096] This process, which involves calculating the target's position information using its distance index and angle estimate, and then associating it with flight paths, may include:

[0097] The unfuzzing velocities in two different directions are compared with the radial velocity direction of the associated track, and the unfuzzing velocity that is the same as the radial velocity direction of the track is selected as the final radial velocity V. r ;

[0098] Thus, the speed range of the TDM-MIMO radar is extended to:

[0099]

[0100] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0101] The TDM-MIMO radar velocity measurement extension method based on array characteristics and track information of the present invention obtains possible virtual array Doppler phase offset compensation by assuming the target's motion direction, performs FFT processing on the compensated virtual array signal to obtain the angle spectrum, utilizes the correlation between the angle spectrum and the ambiguous velocity to obtain two different unambiguous velocities in different directions, and then combines the track information to determine which unambiguous velocity is true, thereby realizing the extension of the velocity measurement range.

[0102] like Figure 6 As shown, the specific implementation steps are as follows:

[0103] For a transmitting antenna number of N t The number of receiving antennas is N r The spacing between array elements is as follows Figure 1 The MIMO radar system shown is, according to Figure 1 The TDM waveform shown has an adjacent transmit antenna pulse interval of T. c Transmit an FMCW signal. The received echo signal is mixed by a mixer to obtain the beat signal.

[0104] The above TDM-MIMO radar system has a defined unambiguous velocity range as follows:

[0105]

[0106] The sampled beat signal is processed by 2D-FFT to obtain the range-Doppler matrix. CFAR is then used to perform target detection on the range-Doppler matrix, yielding the target's range and Doppler index.

[0107] When the direction of the target's motion can be determined, the non-fuzzy velocity range becomes:

[0108] Assuming the target moves away from the radar,

[0109] Assuming the target approaches the radar,

[0110] By selecting an assumption about the target's motion direction, the blurred velocity V of the target under the current assumption is calculated using Doppler indexing. est .

[0111] According to V est Calculate N t Possible Doppler phase biases.

[0112] Assuming the target moves away from the radar

[0113] Assuming target approach radar

[0114] The positional relationship of the array elements in the virtual array is as follows: Figure 2 , Figure 3 As shown, due to the existence of T signals between the transmitted signals of each transmitting antenna... c The time delay means that the moving target and the radar will undergo a displacement over this time interval, resulting in a phase shift along the array dimension. For ease of understanding, assume the number of receiving antennas is N. r =4, let the angle of the moving target be θ, and the phase P of the virtual array signal S is given by the formula.

[0115]

[0116] in, This introduces a step phase for the target in the θ direction. V is the phase deflection caused by the target motion. r The target is the true radial velocity.

[0117] Apply N to the virtual array signal S t Phase is The compensation is obtained as Sc, and FFT is performed on Sc to obtain N. t For angle spectra with phase offset, the peak value is largest when phase offset compensation is correct. The peak values ​​from these angle spectra are compared, and the phase offset compensation corresponding to the largest peak value is selected. As a candidate phase bias, the fuzzy multiplicity m i The velocity fuzziness multiplicity is the candidate, and the angle corresponding to this spectral peak is used as the angle estimate of the target.

[0118] Using m i Calculate the unambiguity resolution rate for the target in two different directions:

[0119] V r+ =V est+ +m i+ ·V max2 Assuming the target moves away from the radar (1)

[0120] V r- =V est- -m i- ·V max2 Assuming the target approaches the radar (2)

[0121] V est+ -V est- =V max2 ,m i+ +m i- +1=N t (3)

[0122] The target's position information is calculated using the target's distance index and angle estimate, and then track association is performed.

[0123] The unfuzzing velocities in two different directions are compared with the radial velocity direction of the associated track, and the unfuzzing velocity that is the same as the radial velocity direction of the track is selected as the final radial velocity V. r .

[0124] This expands the speed range of the TDM-MIMO radar to:

[0125]

[0126] The following section will take a 3-transmitter, 4-receiver TDM-MIMO radar system as an example for further detailed explanation.

[0127] Angle spectrum of a 3-transmitter, 4-receiver TDM-MIMO array under six possible velocity ambiguity conditions. TDM waveform T c =26us, λ=3.75mm, virtual array spacing d=λ, target located in the direction of θ=-4.57°, radial velocity -57m / s.

[0128] The TDM-MIMO radar system described above determines the unambiguous velocity range as [-12.02m / s, 12.02m / s], and the target's motion produces velocity ambiguity.

[0129] The sampled beat signal is processed by 2D-FFT to obtain the range-Doppler matrix. CFAR is then used to perform target detection on the range-Doppler matrix, yielding the target's range and Doppler index.

[0130] Choosing the departure assumption for calculation, the non-fuzzy speed range becomes:

[0131] Assuming the target moves away from the radar, V est ∈[0,24.04m / s]

[0132] V was calculated est =15.12m / s

[0133] According to V est Calculate the three possible Doppler phase biases.

[0134] Assuming the target moves away from the radar

[0135] Three phase biases are applied to the virtual array signal S. The compensation was applied, and FFT processing was performed to obtain three angle spectra under the departure assumption. For ease of understanding... Figure 4 Three angle spectra under the approach assumption are also given.

[0136] Let the possible phase deviation under the departure assumption be: Possible phase deviations under the approach assumption are Therefore, there must be at least one pair. and Make

[0137] k is an integer.

[0138] At this point, the maximum spectral peak of the angle spectrum is no longer uniquely determined, from Figure 4 It can be seen that the peak amplitude values ​​of the angle spectra for [departure, 0th order ambiguity] and [approach, 2nd order ambiguity] are the largest and the angle spectra are completely consistent. It is necessary to distinguish the velocity direction through the track information to determine which case is true.

[0139] The target's position information is calculated using the target's distance index and angle estimate, and then track association is performed.

[0140] Assume the trajectory gives a radial velocity of V. a = -50m / s, and V est With opposite signs, the departure hypothesis is false, and the approach hypothesis is true. V is calculated according to equations (2) and (3). r = -57m / s.

[0141] On the other hand, the target's trajectory speed error may be large in the initial stage of the trajectory, but the speed direction is reliable. Figure 5 Simulation results are presented for a scenario with four moving targets, using a 3 / 4 track initiation method, and then applying the velocity extension method proposed in this invention. Simulation results show that the method of this invention can effectively extend the velocity measurement range of TDM-MIMO radar.

[0142] In summary, the TDM-MIMO radar speed measurement extension method based on array characteristics and track information in this invention can further improve the speed measurement range of TDM-MIMO radar by combining array characteristics and tracking information. On the other hand, most TDM-MIMO radars used in the transportation and automotive fields perform tracking filtering on the target after obtaining target distance, speed, and angle information; therefore, this method does not significantly increase computational complexity. Compared to methods that only utilize array characteristics to extend the speed measurement range, the method proposed in this invention can further extend the speed measurement range, and it does not significantly increase the computational load while greatly improving the speed measurement range of TDM-MIMO radar, making it highly valuable for engineering practice in the transportation and automotive fields.

[0143] It should be noted that all features disclosed in this specification, or all steps in all methods or processes disclosed, may be combined in any way, except for mutually exclusive features and / or steps.

[0144] Furthermore, the specific embodiments described above are exemplary. Those skilled in the art can devise various solutions inspired by the disclosure of this invention, and these solutions all fall within the scope of this invention and its protection. Those skilled in the art should understand that this specification and its accompanying drawings are illustrative and not intended to limit the scope of the claims. The scope of protection of this invention is defined by the claims and their equivalents.

Claims

1. A TDM-MIMO radar velocity measurement extension method based on array characteristics and track information, characterized in that, It includes: Possible virtual array Doppler phase offset compensation is obtained by assuming the target's motion direction; Specifically: the MIMO radar system transmits FMCW signals according to the TDM waveform, and the received echo signals are mixed by a mixer to obtain the beat signal; the unambiguous velocity range of the TDM-MIMO radar system is determined; the sampled beat signal is processed by 2D-FFT to obtain the range-Doppler matrix; the range-Doppler matrix is ​​used to perform target detection using CFAR to obtain the target's range and Doppler index; Assuming the scenario only contains targets moving away from or approaching the radar; calculate the phase P of the virtual array signal S; apply various phase compensations to the virtual array signal S to obtain the virtual array Doppler phase offset compensation S. c ; The angle spectrum is obtained by performing FFT processing on the compensated virtual array signal; Specifically, this involves: compensating for the phase offset of the virtual array Doppler signal. c FFT processing is performed to obtain angle spectra under various phase biases; the peak values ​​of these angle spectra are compared, and the phase bias compensation corresponding to the largest peak value is selected as the candidate phase bias, the corresponding fuzzy multiplicity is the candidate velocity fuzzy multiplicity, and the angle corresponding to this peak value is used as the angle estimate of the target. By utilizing the correlation between the angular spectrum and the fuzzy velocity, two different fuzzy velocities in different directions are obtained; Specifically: The unfuzzy velocity of the target in two different directions is calculated using fuzzy multiplicity, including the unfuzzy velocity of the target when leaving the hypothesis and the unfuzzy velocity of the target when approaching the hypothesis; By combining flight track information, it can determine which unambiguous velocity is true, thereby expanding the velocity measurement range; Specifically, the target's position information is calculated using the target's distance index and angle estimation value, and then track association is performed. The unambiguous velocities in two different directions are compared with the radial velocity direction of the associated track, and the unambiguous velocity that is the same as the radial velocity direction of the track is selected as the final radial velocity, thereby expanding the speed measurement range.

2. The TDM-MIMO radar velocity measurement extension method based on array characteristics and track information according to claim 1, characterized in that, The unambiguous velocity range of the TDM-MIMO radar system is determined as follows: in, This represents the maximum unambiguous velocity that radar can measure. The wavelength of the FMCW signal. The pulse interval between adjacent transmit antennas in the TDM waveform. This refers to the number of transmitting antennas; Assuming the scenario only contains targets moving away from or approaching the radar, the unambiguous velocity range becomes: Among them, V max2 The maximum unambiguous velocity under the current assumptions. The fuzzy velocity of the target under the current assumption; By selecting an assumption about the target's motion direction, the blurred velocity of the target under the current assumption is calculated using Doppler indexing. ; Based on the current assumptions regarding the target's blurred velocity calculate Possible Doppler phase biases: in, The Doppler phase bias is based on the current assumption; Calculate the phase P of the virtual array signal S, assuming the number of receiving antennas in the MIMO radar system is... Let the angle of the moving target be... The phase P of the virtual array signal S is: in, for The direction of the target causes the step phase. The phase deflection caused by the target motion. The true radial velocity of the target; Apply a signal S to the virtual array Phase is The compensation is obtained by virtual array Doppler phase offset compensation S c .

3. The TDM-MIMO radar velocity measurement extension method based on array characteristics and track information according to claim 2, characterized in that, Doppler phase offset compensation for virtual array S c Perform FFT processing to obtain When the phase offset is correctly compensated, the spectral peak of the angle spectrum is the largest when the phase offset is lower. The peak values ​​of these angle spectra are compared, and the phase offset compensation corresponding to the largest peak value is selected. As a candidate phase bias, fuzzy multiplicity The candidate velocity fuzzy multiplicity is used, and the angle corresponding to this spectral peak is used as the angle estimate of the target.

4. The TDM-MIMO radar velocity measurement extension method based on array characteristics and track information according to claim 3, characterized in that, By utilizing the correlation between the angular spectrum and the fuzzy velocity, two types of unfuzzy velocities with different directions are obtained, including: Using fuzzy multiplicity Calculate the unambiguity resolution rate of the target in two different directions: in, The unambiguous velocity of the target when it departs from the assumption. The unambiguity velocity of the target when approaching the assumption. and The fuzzy velocity and fuzzy multiplicity of the target when it departs from the assumption. and The fuzzy velocity and fuzzy multiplicity of the target when approaching the assumption.

5. The TDM-MIMO radar velocity measurement extension method based on array characteristics and track information according to claim 4, characterized in that, The unfuzzy velocities in two different directions are compared with the radial velocity direction of the associated track, and the unfuzzy velocity that is the same as the radial velocity direction of the track is selected as the final radial velocity. ; Thus, the speed range of the TDM-MIMO radar is extended to: 。

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