• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    Extract A directional system containing a large number of direction sensors (11) to monitor a spatial area. Each sensor (11) transmits time series information about possible targets to a remote receiver 5 (13), the time series information being processed by a processor (14) to select at least one frequency line track (23). Several target parameters associated with a frequency line track are processed by a processor (15) to derive tone association information about 10 potential targets, which tone association information is displayed on a display means (16). 1008464
    公开号:NL1008464A
    申请号:NL1008464
    申请日:1997-07-09
    公开日:2016-03-04
    发明作者:Christopher Rossiter Michael
    申请人:Gec-Marconi Ltd；
    IPC主号:
    专利说明:

    IMPROVEMENTS OF OR RELATING TO DIRECTION SYSTEMS
    This invention relates to the resolution of ambiguities associated with a large number of targets in a spatial area monitored by a large number of direction sensors.
    Nowadays, if an unknown number of targets is present in a spatial area that is monitored by a large number of direction sensors at known positions, it is difficult to estimate the number and positions of those targets.
    Ideally, if only the angle of arrival of tone information from a target to a direction sensor can be determined, and if the tone information can be detected by a large number of direction sensors, the position for that target can be found by the bearing intersection of the direction vectors extending from each direction sensor at an angle of arrival of the tone information.
    In practice, however, propagation effects usually limit the number of targets detected by one of such sensors, making it no longer possible to estimate the number and positions of multiple targets by simple examination of the bearing intersection.
    A frequency line track is a tone signal and associated parameters such as bearing estimation (or an angle of arrival at a sensor), signal strength, frequency, or bandwidth.
    It is an object of this invention to prevent or mitigate this drawback.
    According to a first aspect of the present invention, there is provided a direction system for resolving ambiguities associated with a large number of targets in a spatial area to detect transformation from a plurality of targets including a large number of direction sensors arranged in a network in the network spatial area, each directional sensor having a transmitter for transmitting time series information about targets to a remote receiver operatively connected to a processor provided with means for selecting frequency line track information from the time series information, means for frequency line track information provided by comparing neighboring pairs of sensors to derive tone association information about possible target positions, and a display means to display the association information.
    Preferably, a spectrogram may be provided to display tone information derived from the time series information on the display means, and the display means may be arranged to display the association information as an overlay on the spectrogram.
    The direction sensors can be sound buoys.
    The frequency line track information may include time series signals and parameter data associated with the time series signals. The processor may further comprise means for transforming the time series signals into frequency series signals and may also include means for determining discrete frequencies in the frequency series signals. The processor can also determine frequency line tracks from the discrete frequencies that exist for longer than a predetermined time.
    Preferably, the processor may be arranged to derive association information about potential target position by combining weighted summation of polling, Doppler, relationship, and harmonic association proof factors generated by the processor for a selected area of the spatial area, for each frequency line track.
    Preferably, the proof factor for piling association of a frequency line track for a selected area is increased for each direction sensor when an angle of arrival estimate of the frequency line track taken from the center of the selected area is less than or equal to 90 ° from the center of that area.
    Alternatively, the proof factor for piling association of a frequency line track for a selected area is lowered for each direction sensor when an angle of arrival estimate of the frequency line track taken from the center of the selected area is more than 90 ° apart from the center of that area.
    Preferably, the proof factor for Doppler association of frequency line trace for a selected area can be increased for each direction sensor when a substantially equal frequency line trace is determined by the processor for its nearest neighbor direction sensor, when the nearest neighbor direction sensor associates the same frequency line trace has with that selected area, at a substantially equal time and the frequency line tracks are substantially Doppler consistent. The proof factor for Doppler association of a frequency line track for a selected area can also be increased for each direction sensor when substantially equal bandwidth estimates are determined by the processor for the Doppler consistent frequency line tracks. Preferably, the proof factor for Doppler association of a frequency line track for a selected area can also be increased for each direction sensor when substantially equal dispersion estimates are determined by the Doppler consistency frequency line track processor.
    Preferably, the proof factor for ratio association of a frequency line track for a selected area can be increased for each direction sensor when a pair of frequency line tracks for a direction sensor are substantially Doppler consistent with a pair of frequency line tracks for its nearest neighbor direction sensor and substantially have constant frequency ratios between the frequency line tracks of the pairs.
    Preferably, the evidence factor for harmonic association of a frequency line track for a selected area can be increased for each direction sensor when a group, with a size greater than a predetermined minimum, of substantially equivalent harmonic frequency line tracks for the selected area is determined. The evidence factor for harmonic association for a selected area can also be increased for each direction sensor when substantially Doppler-equivalent fundamental frequencies are determined for groups of frequency line traces at that direction sensor and groups of frequency line traces at its nearest neighbor sensor associated with the same selected area.
    Preferably, the processor may be arranged to generate the display for a selected area by combining weighted summation of bearing, Doppler, and ratio association evidence factors for each frequency line track. A weighted summation of bearing, Doppler, ratio, and harmonic evidence factors for a frequency line trace can be used to assign a brightness intensity value to indicate a level of association of the frequency line trace with the selected area. A color line can be assigned to the frequency line tracks in a selected area to differentiate those frequency line tracks from frequency line tracks of other selected areas displayed simultaneously on the display means.
    The method may include deriving tone information from the received time series information, displaying the tone information on a spectrogram, and arranging the association information as an overlay on the spectrogram.
    The frequency line track information may include time series signals and parameter data associated with the time series signals, and the method may transform the time series signals into frequency series signals, select discrete frequencies from the frequency series signals and determine each frequency line track from the discrete frequency series signals longer than one predetermined time.
    The method may include deriving association information about possible target positions by combining a weighted summation of evidence factors for a selected area of the spatial area, using polling, doppler, ratio, and harmonic association calculations for each frequency line trace.
    Preferably, the method may include calculating the evidence factor for bearing association in the selected area by increasing that evidence factor for each direction sensor when an angle of arrival estimate of a frequency line track taken from the center of the selected area is less than or equal 90 ° from the center of that area. Alternatively, the method may include calculating the proof factor for bearing association in the selected area by decreasing that proof factor for each direction sensor when an angle of arrival estimate of a frequency line track taken from the center of the selected area separated by more than 90 ° is from the center of that area.
    Preferably, the method may include calculating a proof factor for Doppler association in the selected area by increasing that proof factor for each direction sensor when a substantially equal frequency line trace exists for that selected area at its nearest neighbor direction sensor, when the most nearby neighbor direction sensor that has equal frequency line trace associated with the selected area at substantially the same time and the frequency line tracks are substantially Doppler consistent. The method may include calculating a Doppler association proof factor in the selected area by also increasing the proof factor for each direction sensor when substantially equal bandwidth estimates exist for the Doppler consistency frequency line traces. The method may include calculating the Doppler association proof factor in the selected area by increasing that proof factor for each direction sensor when substantially equal scatter estimates exist for the Doppler consistent frequency line traces.
    Preferably, the method may include calculating the proof factor for ratio association in the selected area by increasing that proof factor for each direction sensor when a pair of frequency line tracks for that direction sensor are substantially Doppler consistent with a pair of frequency line tracks for its nearest neighbor direction sensor and have substantially equal frequency ratios between the pairs' frequent tracks.
    The method may include calculating the harmonic association evidence factor of a frequency line trace for a selected area by increasing that evidence factor for each direction sensor when a group, of a size greater than a predetermined minimum, determines substantially equivalent harmonic frequency line tracks are for the selected area. The method may include calculating the evidence factor for harmonic association in the selected area by also increasing that evidence factor for each direction sensor when substantially Doppler-equivalent fundamental frequencies are determined for groups of frequency line traces at that direction sensor and groups of frequency line traces at its nearest neighbor direction sensor associated with the selected area.
    Preferably, the method includes generating a spectrogram to display tone information derived from the time series information on a display means and generating the display using an overlay for the spectrogram of a combination of weighted summation for polling, Doppler and relationship association evidence factors generated for the selected area. The method may include assigning a brightness intensity value for each frequency line trace in the selected area using the weighted summation of bearing, Doppler, ratio, and harmonic evidence to establish a level of association of the frequency line trace with the selected area to give. The method may include differentiating frequency line tracks displayed simultaneously on the same display means for a selected area by assigning a color to each selected area and assigning that color to frequency line tracks corresponding to the selected areas.
    The invention is further described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a block diagram of a directional system comprising means for solving target ambiguities; Figure 2 is a block diagram showing the pre-processing; Figure 3 is a block diagram showing a first step of processing, and Figure 4 is a block diagram showing a second step of processing.
    In Figure 1, a directional system 10 is arranged to resolve ambiguities associated with a large number of targets in a spatial area and includes a large number of sound buoys 11, positioned over the entire spatial area, to monitor tone information from a large number of targets and these are operatively connected to respective transmitters 12 for transmitting the time series information to a remote receiver 13.
    The receiver 13 receives the information sent by all transmitters 12 and transmits an input signal 17 to a pre-processor 14 which is operatively connected to a processor 15 which is further operatively connected to a display screen 16. This can be of any suitable form and a spectrogram contain.
    Figure 2 is a block diagram of the pre-processor 14 that receives the input signal 17 containing time series signals and parameter estimates corresponding to each time series signal. The time series signal portion of the input signal 17 is converted by a Fourier transformer 18 into a frequency spectrum signal 19. Discrete frequencies 20 are found in the frequency spectrum signal 19 by using a discrete frequency detector 21. A detector 22 is used to detect frequency line tracks 23 longer than one predetermined time.
    Each frequency line track 23 has a large number of corresponding parameter estimates that provide information about that frequency line track. These can be: (a) A unique identifier. (b) A discrete frequency number indicating the position of the discrete frequency in the frequency spectrum signal 19. (c) An accurate frequency estimate, measured in Hertz. (d) A signal strength determined as a multiple of the theoretical noise standard deviation. (e) An angle of arrival estimate. (f) A count of the number of good side effects. (g) A bandwidth estimate. (h) A distribution estimate.
    The frequency line tracks 23 are transmitted to the processor 15 which determines a reliability factor, for each selected area, that a potential target exists in that area and is separated in first and second steps. The first step 24 (described later with reference to Figure 3) searches for evidence of each sound buoy 14 about a target using the parameter estimates to determine whether a line track 23 can be independently associated with the selected area. The second step 25 (described later with reference to Figure 4) searches for evidence from pairs of sound buoys 11 about a target using the parameter estimates to determine whether pairs of line tracks 23 can be associated with the selected area.
    A problem arises if all possible sound buoy pairs 11 were examined for association with the selected area, since the number of possible pairs is approximately proportional to the square of the number of sound buoys 11. Since many of these pairs would not provide useful information, since their separation to prevent sound buoys 11 from detecting the same targets due to propagation effects, the following processing approach is designed. The number of pairs is set equal to the number of sound buoys 11 and each sound buoy 11 is exclusively associated with its neighbor nearest sound buoy 11.
    Referring to Figure 3, a first element of the first processing step 24 is for each sound buoy to pass the parameter estimation portion for each line track 23 through a filter 26 that selects line tracks 23 that have not previously been separated from the selected area, then updating of a proof factor 27 for bearing association for each line track. Bearing association is a function of bearing separation of a line track from the center of the selected area.
    If the line trace estimate is separated by more than 90 ° from the bearing of the selected area center, the evidence factor 27 is lowered. The line track will be considered as separate from the selected area if the evidence factor 27 is lowered below a specified threshold. If a line track is separated from the selected area, it is not possible that it will be re-associated with that area at a later time.
    If the line trace estimate is less than or equal to 90 ° separated from the selected area center bearing, the following equation describes updating the evidence factor 27. e * + 1 = (ek + A) cos (ö *) where ek The proof factor is 27, A is a constant increase factor and 0k is the angle separation of the line-track bearing estimate of the bearing of the selected area center during the update.
    A threshold for possible association of a line track with a selected area can be derived from the expectation E of the evidence factor 27 by the following equation:
    For example, if the constant A is assigned a value of 0.5 and the line trace is assumed to be associated if the bearing separation is always less than a 31 °, then the expected value is 3. The value 3 provides the threshold for association of a line track 23 with an area. With this threshold, at least seven update intervals for a line track 23 are needed to be associated with an area if the bearing separation is always less than 10 ° and at least eighteen updating intervals if the bearing association is closer to 30 °.
    When a sound buoy 11 will be in the selected area, no change is made to any of the evidence for association of a line track 23 with that area.
    A second element of the first step 24 is determining sets of line tracks 23 from each sound buoy 11 that are likely associated with the selected area and that can be harmonically associated. This is achieved by applying the parameter estimates of the line tracks 23 associated with the selected area to a harmonic detector 28. The harmonic detector 28 makes a fundamental frequency assumption and then determines frequency estimates for the line tracks 23 that can be harmonically associated with that fundamental frequency. When all the line tracks 23 have been checked, a harmonic proof factor 29 is increased if more than three harmonic associations are made. Once a harmonic association of line track 23 has been made, that line track 23 is removed from additional investigations into other harmonic associations.
    Referring to Figure 4, a first element of the second step 25 of processing is to make an investigation to determine whether line tracks 23 are Doppler consistent over a pair of sound cuffs 11. This is achieved by using a Doppler detector 33 to determine a Doppler evidence factor 34 that is increased if a line track 23 exists on the nearest neighbor buoy 11 that meets the following limitations: (a) the line tracks 23 are associated with the same selected area, (b) the line tracks (23) exist in the same update interval, and (c) the line tracks (23) are Doppler consistent.
    A source frequency of a line track is estimated using estimates of speed and course obtained in any suitable way, using the following equation: fs = fo / (1 - u / c cos (Θ - Φ)) where fs and fo the source and observed frequencies are, u is the target speed, c is the sound speed in water, Θ is the bearing estimate for the line track and Φ is the target course.
    In order to allow errors in the rate estimate, two estimates f1 and f2 are made for the source frequency. f1 = fo / (1 - u / c cos (Θ - Φ - ε)) f2 = fo / (1 - u / c cos (Θ - Φ + ε)) where £ is an estimate of the error.
    An upper frequency limit fu and a lower frequency limit f1 are calculated as follows: fu = max (f1, f2) (1 + h / c) f1 = min (f1, f2) (1 - h / c)
    A line track 23 on the nearest neighbor buoy 11 is considered to be Doppler consistent if the frequency estimate for that line track 23 is located between the upper and lower frequency limits fu and f1.
    If a Doppler consistent line track 23 is detected by detector 23 on the nearest neighbor buoy buoy 11, the Doppler proof factor 34 for the line track 23 for the buoy buoy 11 is increased.
    A second element of the second processing step 25 is to determine a ratio proof factor 35 using a ratio detector 36 that searches for line track 23 pairs that have a constant frequency ratio over sound buoy 11 pairs.
    If a line track A on a first sound buoy is Doppler consistent with the line track C on a second sound buoy and a line track B on the first sound buoy is Doppler consistent with the line track D on the second sound buoy, then the line tracks A, B, C suffice. and D to the ratio criterion if the line track frequencies meet the following condition:
    where t represents a tolerance measurement, which is a function of the spectral solution and the individual line track frequencies.
    The ratio proof factor 35 for line tracks A and B should be increased if the criterion is met. The proof factor 35 for the tracks C and D is not increased when the condition is met if the detector 36 is intended to be for a single sound buoy 11 and only the proof factor 35 for that sound buoy 11 is updated.
    A third element of the second processing step 25 is determining whether substantially equal harmonic groups exist at different sound buoys 11 and that both are associated with the selected regions. This is achieved by detecting harmonic groups with a harmonic group detector 37. If the fundamental frequencies for each group are Doppler consistency, then the harmonic evidence factor 29 can be increased.
    A final element of the second processing step 25 is determining whether line tracks 23 that are Doppler consistent have equal bandwidth and distribution estimates. This is achieved by a hand-wide te and spread detector 38. If the line tracks have equal estimates for either bandwidth or spread, the Doppler evidence factor 34 is increased, since the line tracks 23 probably have a common source.
    A reliability factor can be calculated for each selected area and a display for each sensor can be generated. The reliability factor for the existence of a target in a selected area is derived from the functions performed in the first and second steps 24, 25 of the processing. The processor 15 combines the evidence factors for all line tracks 23 on all sound cuffs 11 to derive the reliability factor using the following equation:
    Where CF is the confidence factor for the selected area, W1 and W2 are weighting factors.
    A maximum reliability factor is achieved if each line track 23 associated with the selected area is Doppler consistent with a line track 23 on the nearest neighbor noise buoy and is included in at least one ratio calculation. The reliability factor is low if the selected area does not contain Doppler consistent line traces 23.
    The reliability factor does not include the harmonic proof factor 29 as it does not provide information about how the line tracks 23 are associated about sound buoys.
    A display for each selected area can be generated by assigning a brightness intensity value to indicate the level of association for each line track. The display is preferably in the form of an overlay for a spectrogram 16.
    The brightness intensity value BIV for each line track 23 is determined by the following function: where W1, W2, W3 and W4 represent weighting factors
    BIV = Wl. Regional EF + W2. Doppler EF + W3. Ratio EF * W4. Harmonics EF applied to each of the evidence factors.
    All line traces 23 that are not associated with selected areas will be set to a brightness intensity value of zero. Color can be used to differentiate the results for various selected areas that are displayed simultaneously.
    权利要求:
    Claims (36)
    [1]
    A direction system, for resolving ambiguities associated with a large number of targets in a spatial area to detect transformation from a number of targets, comprising a large number of direction sensors arranged in a network in the spatial area, each direction sensor being a transmitter for transmitting time series information about targets to a remote receiver operatively connected to a processor provided with means for selecting frequency line track information from the time series information, means for comparing the frequency line track information provided by neighboring pairs of sensors to display tone association information about possible target positions, and a display means to display the association information.
    [2]
    A directional system according to claim 1, comprising a spectrogram for displaying tone information derived from the series information (17) on the display means (16), characterized in that the display means (16) is arranged to display the association information to give as an overlay on the spectrogram.
    [3]
    A directional system according to claim 1 or 2, characterized in that the directional sensors (11) are sound buoys.
    [4]
    A directional system according to any one of the preceding claims, characterized in that the frequency line track information (23) contains time series signals and parameter data associated with the time series signals (17).
    [5]
    A directional system according to claim 4, characterized in that the processor (15) further comprises means (18) for transforming the time series signals (17) into frequency series signals (19).
    [6]
    A directional system according to claim 5, characterized in that the processor (15) also comprises means (21) for determining discrete frequencies (20) in the frequency series signals (19).
    [7]
    A directional system according to claim 6, characterized in that the processor (15) also determines frequency line tracks (23) from the discrete frequencies (20) that exist longer than a predetermined time.
    [8]
    A targeting system according to any one of the preceding claims, characterized in that the processor (15) is arranged to derive association information about possible target positions by the combination of weighted summation of bearing (27), Doppler (34) , ratio (35) and harmonic (29) association factors, generated by the processor (15), for a selected area of the spatial area, for each frequency line track (23).
    [9]
    A directional system according to claim 8, characterized in that the proof factor (27) for bearing association of a frequency line track (23) for a selected area is increased for each direction sensor (11) when an angle of arrival estimate of the frequency line track (23), taken from the center of the selected area, is less than or equal to 90 ° separated from the center of that area.
    [10]
    A directional system according to claim 8, characterized in that the evidence factor (27) for bearing association of a frequency line track (23) for a selected area is lowered for each direction sensor (11) when an angle of arrival estimate of the frequency line track (23), taken from the center of the selected area, is more than 90 ° separated from the center of that area.
    [11]
    A directional system according to claims 8 to 10, characterized in that the proof factor (34) for Doppler association of frequency line track (23) for a selected area is increased for each direction sensor (11) when a substantially equal frequency line track (23) is determined by the processor (15) for its nearest neighbor direction sensor (11), when the nearest neighbor direction sensor (11) has the same frequency line track (23) associated with that selected area, at a substantially equal time and the frequency line tracks (23) are substantially Doppler consistent.
    [12]
    A directional system according to claim 11, characterized in that the evidence factor (34) for Doppler association of a frequency line track (23) for a selected area is also increased for each direction sensor (11) when substantially equal bandwidth estimates are determined by the processor (15) for the Doppler consistency frequency line tracks (23).
    [13]
    A directional system according to claim 11 or 12, characterized in that the proof factor (34) for Doppler association of a frequency line track (23) for a selected area is also increased for each direction sensor (11) when substantially equal distribution - estimates are determined by the Doppler consistency frequency line processor (15) processor (15).
    [14]
    A directional system according to claims 8 to 13, characterized in that the proof factor (35) for ratio association of a frequency line track (23) for a selected area is increased for each direction sensor (11) when a pair of frequency line tracks (23) a direction sensor (11) being substantially Doppler consistent with a pair of required line tracks (23) for its nearest neighbor direction sensor (11) and having substantially constant frequency ratios between the frequency line tracks (23) of the pairs.
    [15]
    A directional system according to claims 8 to 14, characterized in that the evidence factor (29) for harmonic association of a frequency line track (23) for a selected area is increased for each direction sensor (11) when a group, with a size greater than a predetermined minimum, of substantially equivalent harmonic frequency line tracks (23) for the selected range.
    [16]
    A directional system according to claim 15, characterized in that the evidence factor (29) for harmonic association for a selected area is also increased for each direction sensor (11) when substantially Doppler-equivalent fundamental frequencies are determined for groups of frequency line tracks (23) at that direction sensor (11) and groups of frequency line tracks (23) at its nearest neighbor direction sensor (11) associated with the same selected area.
    [17]
    A pointing system according to any of claims 8 to 16, characterized in that the processor (15) is arranged to generate the display for a selected area by combining weighted summation of polling (29), Doppler (34) and ratio (35) association proof factors for each frequency line track (23).
    [18]
    A directional system according to claim 17, characterized in that a weighted summation of bearing (27), Doppler (34), ratio (35) and harmonic (29) association proof factors for a frequency line track (23) is used to assign a brightness intensity value to indicate a level of association of the frequency line trace (23) with the selected area.
    [19]
    A directional system according to claim 17 or 18, characterized in that frequency line tracks (23) in a selected area are assigned a color to differentiate those frequency line tracks (23) from frequency line tracks (23) of other selected areas displayed simultaneously on the display means (16).
    [20]
    20. A method for resolving ambiguities associated with a large number of targets in a spatial area to detect information from a plurality of targets, including deploying a large number of directional sensors in a spatial area, transmitting time series information about targets in the spatial area for the direction sensors to a remote receiver, processing received time series information to select frequency line track information, comparing the frequency line track information provided by neighboring pairs of sensors to derive tone association information about possible target positions, and displaying the association information on a display means.
    [21]
    A method according to claim 20, characterized by deriving tone information (17) from the received time series information, displaying the tone information on a spectrogram and arranging the association information as an overlay on the spectrogram.
    [22]
    A method according to claim 20 or 21, and wherein the frequency line track information (23) comprises time series signals and parameter data associated with the time series, characterized by transforming the time series signals (17) into frequency series signals (19).
    [23]
    A method according to claim 22, characterized by selecting discrete frequencies (20) from the frequency series signals (19).
    [24]
    A method according to claim 23, characterized by determining each frequency line track (23) from the discrete frequencies (20) that exist longer than a predetermined time.
    [25]
    A method according to any of claims 20 to 24, characterized by deriving association information about possible target positions by combining a weighted summation of evidence factors for a selected area of the spatial area, using polling (27), Doppler (34), ratio (35) and harmonic (29) association calculations for each frequency line track (23).
    [26]
    A method according to claim 25, characterized by calculating the evidence factor (27) for bearing association in the selected area by increasing that evidence factor (27) for each direction sensor (11) when an angle of arrival estimate of a frequency line track (23), taken from the center of the selected area, is less than or equal to 90 ° separated from the center of that area.
    [27]
    A method according to claim 25, characterized by calculating the evidence factor (27) for bearing association in the selected area by decreasing that evidence factor (27) for each direction sensor (11) when an angle of arrival estimate of a frequency line track (23), taken from the center of the selected area, is more than 90 ° separated from the center of that area.
    [28]
    A method according to any one of claims 25 to 27, characterized by calculating a Doppler association proof factor (34) in the selected area by increasing that proof factor (34) for each direction sensor (11) when a substantially equal frequency line track (23) exists for that selected area at its nearest neighbor direction sensor (11), when the nearest neighbor direction sensor (11) has that same frequency line track associated with the selected area at substantially the same time and the frequency line tracks (23) in mainly Doppler consistent.
    [29]
    A method according to claim 28, characterized by calculating a Doppler association proof factor (34) in the selected area by also increasing the proof factor (34) for each direction sensor (11) when substantially equal bandwidth estimates exist for the Doppler consistency frequency line tracks (23).
    [30]
    A method according to claim 28 or 29, characterized by calculating the Doppler association proof factor (34) in the selected area by increasing that proof factor (34) for each direction sensor (11) when substantially similar distribution estimates exist for the Doppler consistent frequency line tracks (23).
    [31]
    A method according to any one of claims 25 to 30, characterized by calculating the proof factor (35) for ratio association in the selected area by increasing that proof factor (35) for each direction sensor (11) when a pair of frequency line traces (23) for that direction sensor (11) are substantially Doppler consistent with a pair of frequency line traces (23) for its nearest neighbor direction sensor (11) and have substantially equal frequency ratios between the frequency line traces (23) of the pairs.
    [32]
    A method according to claims 25 to 31, characterized by calculating the proof factor (29) for harmonic association of a frequency line track (23) for a selected area by increasing that proof factor (29) for each direction sensor (11) when a group of dimensions greater than a predetermined minimum of substantially equivalent harmonic frequency line tracks (23) are determined for the selected area.
    [33]
    A method according to claims 25 to 32, characterized by calculating the proof factor (29) for harmonic association in the selected area by also increasing that proof factor (29) for each direction sensor (11) when substantially Dop Pler-equivalent fundamental frequencies are determined for groups of frequency line tracks (23) at that direction sensor (11) and groups of frequency line tracks (23) at its nearest neighbor direction sensor (11) associated with the selected area.
    [34]
    A method according to any one of claims 25 to 33, characterized by generating a spectrogram to display tone information derived from the time series information (17) on a display means (16) and generating the display under using as a spectrogram overlay a combination of weighted summation for bearing (27), Doppler (34) and ratio (35) association proof factors generated for the selected area.
    [35]
    A method according to claim 34, characterized by assigning a brightness intensity value for each frequency line trace (23) in the selected area using the weighted summation of bearing (27), Doppler (34), ratio (35) ) and harmonic (29) evidence factors to indicate a level of association of the frequency line track (23) with the selected area.
    [36]
    A method according to claim 34 or 35, characterized by differentiating frequency line tracks (23) displayed simultaneously on the same display means (6) for a selected area by assigning a color to each selected area and assigning that color on frequency line tracks (23) corresponding to the selected areas.
    类似技术:
    公开号 | 公开日 | 专利标题
    US7460052B2|2008-12-02|Multiple frequency through-the-wall motion detection and ranging using a difference-based estimation technique
    US7355545B2|2008-04-08|Through the wall ranging with triangulation using multiple spaced apart radars
    US20060284757A1|2006-12-21|Through-the-wall frequency stepped imaging system utilizing near field multiple antenna positions, clutter rejection and corrections for frequency dependent wall effects
    JP2021505892A|2021-02-18|Radar processing chain for FMCW radar system
    EP0236331A1|1987-09-16|Methods of detection and identification of one or more remote objects.
    US5475651A|1995-12-12|Method for real-time extraction of ocean bottom properties
    JP2021505892A5|2022-01-11|
    US7528764B2|2009-05-05|Through the wall ranging with triangulation using multiple spaced apart radars
    JPH0921864A|1997-01-21|Method for detecting target in clutter by using radar systemand strength and angle of target
    RU2620963C1|2017-05-30|Surveillance monitoring method of trilateral road fork
    EP1711844B1|2009-10-14|Multiple frequency through-the-wall motion detection and ranging using difference-based estimation technique
    CN110431437A|2019-11-08|Method and apparatus for seeking the laterally relative speed component of radar target
    NL1008464B1|2016-03-15|Improvements from or with regard to directional systems.
    RU2626742C1|2017-07-31|Method for security monitoring an intersection location of three roads
    Chiu et al.2008|RADARSAT-2 moving object detection experiment |
    EP3553552A1|2019-10-16|Method for the recognition of a moving pedestrian
    US6462702B1|2002-10-08|Doppler-based traffic radar system
    US8102310B2|2012-01-24|Dismount step discrimination with temporal adaptive matched filtering of doppler spectral features
    US4719467A|1988-01-12|Doppler imaging of targets
    RU2636058C1|2017-11-20|Method for processing radar signals in mono-pulse radiolocation station
    RU2311686C2|2007-11-27|Method for detection and determination of present location of violator of guardeozone
    GB2521094A|2015-06-17|Improvements in or relating to targeting systems
    JP3513057B2|2004-03-31|Wide-area control support system
    JP2004517420A|2004-06-10|Method and apparatus for estimating motion parameters of a target
    US20210003692A1|2021-01-07|Velocity measurement device, velocity measurement program, recording medium, and velocity measurement method
    同族专利:
    公开号 | 公开日
    US9229087B1|2016-01-05|
    GB9619023D0|2013-12-11|
    GB9614398D0|2013-12-11|
    NL1008464B1|2016-03-15|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    GB2253107B|1982-03-05|1993-01-13|Philips Electronic Associated|Locating moving radio sources|
    US4717916A|1986-05-16|1988-01-05|Holodyne Ltd., 1986|High resolution imaging doppler interferometer|
    US4811308A|1986-10-29|1989-03-07|Michel Howard E|Seismo-acoustic detection, identification, and tracking of stealth aircraft|
    US5175710A|1990-12-14|1992-12-29|Hutson William H|Multi-dimensional data processing and display|
    CA2105462A1|1993-09-02|1995-03-03|Brian H. Maranda|Target detector and localizer for passive sonar|
    GB9420742D0|1994-10-14|1994-11-30|Lewis Owen M|Data processing apparatus and technique|
    GB2521094B|1996-07-09|2016-03-23|Thomson Marconi Sonar Ltd|Improvements in or relating to targeting systems|
    GB9621221D0|1996-10-11|2002-08-14|Thomson Marconi Sonar Ltd|Target discriminator|
    法律状态:
    2017-07-12| MK| Patent expired because of reaching the maximum lifetime of a patent|Effective date: 20170708 |
    优先权:
    申请号 | 申请日 | 专利标题
    GBGB9614398.7A|GB9614398D0|1996-07-09|1996-07-09|Targeting system|
    GBGB9619023.6A|GB9619023D0|1996-07-09|1996-09-11|Targeting system|
    [返回顶部]