WO2000026690A1 - Adaptive dwell timing for radar tracking - Google Patents
Adaptive dwell timing for radar tracking Download PDFInfo
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- WO2000026690A1 WO2000026690A1 PCT/US1999/025449 US9925449W WO0026690A1 WO 2000026690 A1 WO2000026690 A1 WO 2000026690A1 US 9925449 W US9925449 W US 9925449W WO 0026690 A1 WO0026690 A1 WO 0026690A1
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Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
- G01S13/88—Radar or analogous systems specially adapted for specific applications
- G01S13/91—Radar or analogous systems specially adapted for specific applications for traffic control
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
- G01S13/66—Radar-tracking systems; Analogous systems
- G01S13/72—Radar-tracking systems; Analogous systems for two-dimensional tracking, e.g. combination of angle and range tracking, track-while-scan radar
- G01S13/723—Radar-tracking systems; Analogous systems for two-dimensional tracking, e.g. combination of angle and range tracking, track-while-scan radar by using numerical data
- G01S13/726—Multiple target tracking
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/02—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00
- G01S7/28—Details of pulse systems
- G01S7/285—Receivers
- G01S7/295—Means for transforming co-ordinates or for evaluating data, e.g. using computers
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
- G01S13/74—Systems using reradiation of radio waves, e.g. secondary radar systems; Analogous systems
- G01S13/76—Systems using reradiation of radio waves, e.g. secondary radar systems; Analogous systems wherein pulse-type signals are transmitted
- G01S13/78—Systems using reradiation of radio waves, e.g. secondary radar systems; Analogous systems wherein pulse-type signals are transmitted discriminating between different kinds of targets, e.g. IFF-radar, i.e. identification of friend or foe
- G01S13/781—Secondary Surveillance Radar [SSR] in general
Definitions
- the present invention relates to air traffic control (“ATC”) radar systems, and more particularly to a data processing system for an air traffic control radar system.
- ATC air traffic control
- MODE-S Mode Select Beacon System Sensor
- the primary target responses depend upon a reflection of a radar pulse of short duration from, for example, an aircraft wherein the range ofthe aircraft is determined from the round-trip time ofthe radar pulse.
- the secondary target data rely upon a response from a transponder or beacon located in the aircraft upon interrogation ofthe aircraft by a transmitted radar pulse transmitted by the ground-based antenna.
- the transponder response may indicate range, bearing, altitude, and identity of such aircraft.
- the radar antenna can be mechanically or electronically scanned and typically focuses the radar pulses in a fairly narrow angular beam.
- a system incorporating an electronically-scanned antenna is disclosed, for example, in U.S. Patent No. 5,825,322.
- a transmitter controlled by data processing electronics typically controls the signal strength and the duration ofthe pulses emitted by the antenna.
- the antenna commonly also serves as a receiver for returning signals, which are received when the antenna points at a target, but may also include superimposed interference signals due to noise.
- Data processing electronics processes the received signals using known processing algorithms to extract, for example, the position, velocity, direction of motion, and the type of target.
- a “target report” is an association of target data (r, ⁇ ) with a specific object (target).
- a “target track” is a time-sequence of target reports that have a high probability of being correlated and may be visually displayed indicating a "course” ofthe target.
- “Correlation” is a process used to establish a connection between multiple target reports.
- Search acquisition time is the time required to scan a wedge- shaped area bounded by a predetermined arc and a predetermined distance from the radar site.
- a “search radius” is the radius of a circular area surrounding a target in which the target is expected to be located in a subsequent radar scan.
- “Process delay time” refers to the time required to organize and buffer incoming and outgoing data.
- the buffering process typically introduces "jitter” in the target data causing a time spread in the arrival time ofthe data at the STARS processor.
- the "Dwell delay” is defined as the sum ofthe “jitter” due to process delay of incoming data (see above) and the time needed for the radar to scan all potential targets within the search radius of a target being tracked.
- the STARS processing system is subject to various regulatory and technical requirements.
- One aspect ofthe ofthe STARS system requirements relates to data processing times; that is, to satisfy STARS requirements, certain specified data processing tasks may not exceed certain predefined time intervals. These time intervals are specified by statistical measures requiring, for example, that 95% ofthe targets are properly identified and correlated with a target track within 1 second for radar scenarios with a mixture of primary and secondary received target data.
- Systems processing target data must provide reliable results within the specified data processing time even under challenging conditions, such as garble, malfunction or a total failure of a secondary radar site.
- a controller must be able to rely on information received from the primary radar which lacks the identity code ofthe target otherwise supplied by the airborne transponder or beacon.
- Beacon reports from airborne transponders may be garbled in high traffic areas (target bunching), making it difficult to compile a reliable target report and ultimately a target track.
- Targets most likely to be misidentified are those having a relatively high angular velocity relative to the antenna, such as targets moving at high speed and/or targets located close to the radar site. Also, target tracks crossing at a shallow angle may be subject to swapping of identities.
- a conventional radar tracking system may typically use a fixed dwell time of 450 ms and attempts to correlate target data with a target track every 150 ms, hereinafter to be referred to as a time "quantum.”
- a fixed dwell time for all target ranges, for short- and long- range radars, and for radars with different antenna periods is a compromise, since the search acquisition time for a defined search radius depends on the distance ofthe target from the antenna, and the antenna period.
- the search acquisition time may be 0.5 second so that the fixed dwell time of 450 ms is insufficient.
- a search acquisition time of only 50 ms may be sufficient for distant targets which can therefore be correlated with a target track within a much shorter time.
- a radar processing system processing target data with a constant 450 ms dwell time for all situations therefore appears to be inefficient and makes it difficult to satisfy a mandated one second response time for processing, correlating and displaying STARS target data as target tracks in 95% ofthe acquired target samples under all conditions.
- a radar system relying primarily on radar signals reflected from a target for correlating target data between different antenna scans has a processor which processes the received target data with a search acquisition time that is adapted to the distance of the target from the radar site.
- the radar system may be part of a conventional air traffic control (“ATC") radar system, such as the STARS ATC system.
- ATC air traffic control
- a radar system includes an antenna acquiring radar signals from a target, with the radar signals providing target data representing spatial coordinates ofthe target.
- a processor produces a target report corresponding to the target by correlating with the target during a search acquisition time one ofthe target data having coordinates within a predetermined range ofthe target. The search acquisition time for the target data having coordinates within the predetermined range is adjusted depending on the distance ofthe target from the radar site.
- Embodiments ofthe invention may include one or more ofthe following features.
- the processor may also correlate the target report with a target track which can be displayed on a display.
- the search acquisition time depends on operating parameters ofthe radar system and may also depend on at least one ofthe velocity, acceleration and maneuvers ofthe target.
- the operating parameters may include a rotation period ofthe antenna and a beam width of a radar beam emitted by the antenna.
- At least one additional antenna may be provided to supply additional target data, with the additional target data supplied to and processed by the processor.
- the antenna or antennas may be connected to the processor via a gateway and communication links implemented as serial data links and/or LANs.
- a processor of a radar system for correlating target data with a target track includes input means which obtain target data of a radar target, and processing means which produce within a processing time period a target report corresponding to the target by correlating with the target one ofthe target data having coordinates within a predetermined range ofthe target.
- the processor further includes output means providing displayable signals correlated with the target report.
- the processing time period is determined according to at least one ofthe spatial coordinates ofthe target with respect to the radar site.
- Embodiments ofthe invention may include one or more ofthe following features.
- the displayable signals may be displayed on a display monitor as a target track, wherein the target track represents a sequence of target reports that have a high probability of being correlated.
- the displayable signals may be stored in a memory for further processing and/or analysis.
- the target data received by the input means may include the target data from at least one primary antenna and at least one secondary antenna.
- the target report and/or the target track may be formed from an identification code ofthe secondary antenna, if the identification code ofthe secondary antenna is intelligible, and from the target data ofthe primary antenna and at least a portion of the target data of the secondary antenna, if the identification code of the secondary antenna cannot be extracted from the data.
- Methods of radar tracking are also provided herein, including providing a radar acquisition system with at least one antenna, wherein the system produces target data from at least the target, determining a search acquisition time based on at least one ofthe coordinates ofthe target and a search range, and correlating during the search acquisition time target data obtained during successive scans ofthe antenna and located within the search range to form a target track.
- Embodiments ofthe method ofthe invention may include one or more ofthe following features.
- Correlating target data may include executing a correlation process during a quantized time period, and repeating the correlation process for subsequent quantized time periods until the target data are correlated or a predetermined timer has expired.
- Correlating target data may also include assigning a probability for the target data of being representative ofthe target based on a motion characteristics ofthe target, which may include a velocity, acceleration and/or direction of movement ofthe target.
- the predetermined range ofthe target may be substantially independent ofthe distance ofthe target from the radar site, and the search acquisition time may therefore be shorter for targets that are more distant from the radar site.
- a computer program residing on a computer-readable medium, includes instructions for causing a computer to accept radar target data representing spatial coordinates of a target and acquired during successive scans of a radar antenna, and to select from a subsequent scan target data having coordinates within a predetermined range ofthe spatial coordinates ofthe target determined during a previous scan.
- the instructions further cause the computer to compute a search acquisition time based on the predetermined range, and to correlate during the search acquisition time the target data with a target track.
- the search acquisition time may be shorter for targets that are more distant from the radar antenna than for targets that are closer to the radar antenna.
- Correlating the target data with a target track may include executing a correlation routine during a dwell delay time which includes the search acquisition time and a jitter, wherein the dwell delay time is subdivided into time quanta having a predetermined time duration.
- FIG. 1 is a schematic block diagram of a radar system
- FIG. 2 is a data flow diagram of an air traffic control radar system incorporating primary and secondary antennas
- FIG. 3 shows beacon reports of an exemplary secondary short range radar system
- FIG. 4 shows uncorrelated target data of an exemplary primary short range radar system
- FIG. 5 is a timing diagram ofthe radar system of FIG. 1,
- FIG. 6 shows the coverage provided by the radar system of FIG. 1 and corresponding search areas
- FIG. 7 shows the search acquisition time according to an embodiment ofthe invention
- FIGS. 8 and 9 shows the dwell delay time for the short range radar of FIG. 4, and FIG. 10 is a process flow chart for correlating target data.
- the average time required to process target data and to correlate the target data with track data can be shortened by using a variable search acquisition time for more distant targets. With the shorter search acquisition time, cycle time (quantum) in the processor can also be decreased.
- a conventional air traffic control radar system includes a radar acquisition system 10 with a primary and/or secondary radar antenna 11 mounted on a rotating mechanical pedestal 12.
- a transmitter portion of a transmitter/receiver/processor 14 (shown as a single unit) supplies target data via a link 13 to the antenna 11 for transmission.
- the transmitter/ receiver/ processor 14 may be a single unit or several cooperating units (not shown).
- the transmitter portion 14 is a conventional radar transmitter, comprising electronics and software.
- the signals from the transmitter portion 14 determine the nature ofthe interrogation signals sent by the antenna 11.
- the antenna 11 is also connected via the link 13 to a receiver portion ofthe transmitter/ receiver/ processor 14, comprising conventional electronics and software for receiving and relaying return signals received by the antenna 11.
- the pedestal 12 may support both the primary antenna 11 and a secondary antenna (not shown) which may be integrated in the primary antenna 11 and may transmit an interrogation signal to beacon- or transponder- equipped aircraft (not shown).
- the secondary antenna may be scanned mechanically or electronically, as mentioned above.
- Typical primary target data are preferably in digital form and encoded in polar coordinates (r, ⁇ ).
- the target data reflect the round trip time ofthe radar pulse between the antenna and the target and the azimuthal position ofthe target with respect to a reference direction, such as true North, and are transmitted via a link 15, such as a serial communication channel, to a common gateway 16.
- additional radar acquisition systems 10' including both primary and secondary antennas may be connected to the gateway 16 via additional links 15', as is known in the art.
- the gateway 16 is connected via a link 17, which may be implemented as a LAN, to a STARS processor 18 which buffers and correlates the target data to produce target track reports.
- the correlated data are then transmitted via a link 19 which may also be a LAN, for display on a radar display 20 located, for example, at an ATC facility (not shown). Alternatively or in addition, the correlated data may also be stored in a memory (not shown).
- target data are received by the primary antenna receiver/processor, step 24, and the secondary antenna receiver/processor, step 24', and transmitted to a primary antenna buffer, step 26, and a secondary antenna buffer, step 26', respectively.
- the identification code can be extracted from the secondary radar data, step 28, then the data from the secondary radar can be unambiguously correlated with a target track and displayed on a display 20 or stored in a memory (not shown), as the case may be, without relying on the primary radar data.
- the identification code ofthe secondary target data contains errors so that the data cannot be reliably analyzed, then an attempt will be made to extract as much useful information from the secondary target data as possible so as to correlate the secondary target data with the existing radar tracks, thereby enhancing the reliability ofthe target report prepared from the primary target data, step 30.
- target tracks based on beacon reports received from the aircrafts' transponders by an exemplary secondary radar antenna ofthe Boston Short Range radar system are shown for 94 consecutive scans with a scan duration of 4.6 seconds, corresponding to a total scan time of 7.2 minutes.
- the horizontal axis represents the azimuthal position ofthe antenna over a full scan of 360 degrees, and the vertical axis the distance ofthe target from the radar site in nautical miles (nm).
- the radar system has a range of about 30 nm.
- the course of a target that would show as a straight line on a polar diagram is represented by a curve similar to a hyperbola. As seen in FIG. 3, most points on the display appear to be correlated with a target track and may be uniquely identified.
- target data received by an exemplary primary radar antenna ofthe Boston Short Range radar system are shown for 94 consecutive scans, with a scan duration of 4.6 seconds, corresponding to a total scan time of 7.2 minutes.
- the horizontal axis represents the azimuthal position ofthe antenna over a full scan of 360 degrees, and the vertical axis the distance ofthe target from the radar site in nautical miles.
- the exemplary primary radar system has a range of about 60 nm.
- the distances and azimuth angles are derived from the radar echos received by the primary antenna alone, without the benefit of input from the secondary antenna.
- the individual data points (blips) include, as mentioned above, not only the radar echo reflected from the targets, but may also include reflections from fixed structures, moving radar reflectors which are not targets, such as birds, and other noise. The noise will depend on the set sensitivity ofthe system.
- a radar system able to detect smaller targets will have a higher sensitivity and therefore more noise than a system optimized for the detection of larger airplanes. It is apparent from FIG. 4 that a correlation between the displayed blips and the moving targets and therefore the generation of a target track is difficult, in particular when the targets are bunched or moving fast or changing speed and direction.
- the maximum time period T max of 1 second allocated for target correlation begins when the target data are received by the processor 18 (FIG.
- T max a dwell delay time T dd , and an output processing delay time 44, whereas the processing delay 40 due to the equipment ofthe radar acquisition system 10, 10' and the transmission channels 15, 16 and 17 are excluded.
- the target data do not arrive at the input of processor 18 in the order they were received by the radar antenna 11 , but may suffer a random delay caused by, for example, processing steps performed in processor 14. This random delay is indicated in FIG. 5 as jitter 46 with a time duration T of typically 50 ms.
- the dwell delay time T dd is the sum of the jitter 46 and the search acquisition time (T sa ) 42.
- the STARS processor 18 cycles through the received target data and executes one complete cycle through each time quantum 48 a , 48 b , ..., 48 n .
- a typical ATC system presently in use operates with a fixed dwell delay time T dd of 450 ms and a time quantum duration of 150 ms.
- the exemplary first time quantum 48 a is longer than the duration ofthe jitter 46 and includes the jitter 46. If the jitter 46 has a longer time duration than the time quantum, then the jitter 46 may occupy two or more time quanta 48 a , 48 b , ... .
- the processor 18 may be able to correlate all the target data within two or three time quanta, in which case the dwell delay time T dd may be significantly shorter than the 450 ms allocated in conventional radar systems to perform the correlation process. This will be the case in particular when the targets are at a greater distance from the radar site, as will now be described in detail.
- a primary radar site R scans a radar beam 52 which at successive time intervals will assume directions 52', 52", 52'" and so on.
- the radar has a minimum and maximum range depicted by the circles 54 and 56, respectively.
- the exemplary primary short range antenna discussed with reference to FIGS. 3 and 4 may have the antenna period of 4.6 seconds.
- the beam 52 exemplary antenna advances to the beam direction 52' subtending an angle of 32.4 degrees between 52 and 52'.
- a target R located initially at the center of circle 58 at a distance 60 from the radar site may cover a distance 62 from the center ofthe circle 58.
- the radius 62 is called "search radius" and depends on a number of characteristics, including the speed and acceleration/deceleration ofthe target. Only target data points located inside the search area 58 will be examined for correlation with a previous established target data point or target report.
- One actual search radius 58 of a short range radar producing low noise, high-quality tracks is approximately 1 nautical mile, corresponding to a scan angle of 11.5 degrees subtended between the radar beams 52 and 52' for a target distance 60 of 10 nm. The angle of 11.5 degrees is scanned during approximately 140 ms which approximately is the time duration of a processing quantum presently used in a conventional ATC system.
- the search radii used in actual radar systems depend slightly on the distance from the radar site to accommodate the distance-dependent beam size and noise. For example, the search radius may be 0.6 nm at a distance of 4 nm, increasing to 1.1 nm at a distance of 60 nm. The scope ofthe invention is not limited by an actual variation ofthe search radius with distance.
- the search acquisition time can be reduced for the more distant targets due to the constant angular velocity ofthe mechanically scanned antenna.
- the angle between 52" and 52'" is 1.9 degrees, corresponding to a search acquisition time of 24 ms for the exemplary short range radar having an antenna period of 4.6 seconds.
- more distant target data and target reports may be correlated within a shorter time than target data originating from closer targets.
- FIG. 7 shows a typical search acquisition time expressed in ms for the exemplary short range radar in a circular search area with a radius increasing steadily from 0.6 nm for a target distance of 4 nm to 1.1 nm for a target distance of 60 nm.
- the search acquisition times are listed in the right-hand column of Table 1 and illustrated in FIG. 7. As seen from curve 72 of FIG. 7, the search acquisition times are considerably shorter than the presently used processing quantum of 150 ms, except for targets very close to the radar site. It can therefore be expected that shorter processing quanta can significantly reduce the dwell delay time T dd 42 and thereby also the maximum processing time T max of 1 second without degrading the overall performance ofthe radar system.
- processing ofthe radar signal and correlation with target reports and target tracks in the STARS processor 18 is "quantized,” meaning that during each process "quantum” the processor 18 cycles through all the data once to establish correlation.
- the dwell delay time 42 to correlate a particular radar signal with a target report to establish a target track can be determined as the sum of the jitter delay 46 inherent in the transmission ofthe target data from the radar acquisition system 10 to the processor 18 and the processing time to establish correlation, with the result rounded up to the next quantum.
- One formula for the dwell delay time T dd measured in ms for a particular target report is:
- FIG. 8 shows a graphic representation ofthe total delay time T dd computed with
- the average total delay time can be further reduced by using quanta of shorter duration which may require faster processors 18 and correlators.
- a quantum duration of 30 ms is used to compute the total delay time shown as curve 92.
- the average total delay time is hereby reduced to approximately 130 ms, as depicted by the horizontal line 98.
- a quantum duration of 100 ms increases the average total delay time to 212 ms (not shown).
- shorter quanta can reduce the average delay time.
- the major reduction in the total delay time is due to the significantly shortened search acquisition times for the more distant targets listed in Table 1 and shown in FIG. 7.
- ATC radar system As mentioned above, under STARS guidelines, five percent of responses are allowed to exceed one second.
- a small number of residual target data that cannot be correlated with a target track, or target tracks that cannot be correlated with target data may be processed in compliance with the conventional correlation algorithm allowing for a maximum total dwell delay time of 450 ms.
- these target data and target tracks can then be either sent to the display and discarded from the wait queue, or discarded from the wait queue without being sent to the display, as described below.
- the system disclosed herein can reduce the average dwell time by approximately 250-300 ms out of 450 ms.
- the system can also reduce the frequency of correlation errors for targets that are close to a primary radar antenna by accommodating the longer dwell delay times for closer targets within the limits ofthe maximum statistically permissible overall dwell delay.
- a process flow chart 100 depicts processing steps by which the processor 18 may take advantage ofthe variable dwell time disclosed herein.
- the processor 18 receives target data from the gateway 16 via the communications link 17, step 102.
- the target data may be in digital form and include a header and coordinate information about the target, such as the target's distance d from the radar site and the azimuthal angle ⁇ .
- processor 18 determines, for example from Table 1 , the search acquisition time associated with the particular target data, step 104.
- the processor accounts for the time jitter introduced by the radar processor 14 and the buffer 16, step 106.
- the jitter may be determined experimentally, with the corresponding value periodically updated and stored in a memory located, for example, in the processor 18 (not shown).
- a set processing quantum determines a fixed cycle time (time quantum) during which the processor 18 attempts to correlate the target data received from the gateway 16 with target reports to establish or continue a target track, step 108.
- the processing time quantum may be a constant depending on the processing capabilities ofthe processor 18.
- a timer is started which counts by process quanta and runs until target data and target reports have been correlated.
- the process compares the target data with target reports, step 112.
- Target data of targets distant from the radar site and having a short search acquisition time can be correlated more quickly, for example within one or two time quanta, step 114, and the correlated target data are sent to the display and/or transmitted or stored for further processing, step 120.
- step 116 For target data that are not correlated with radar reports, the process goes to step 116 to check if the timer has expired, i.e., if the timer has reached the maximum permitted dwell delay time of 450 ms. If the timer has not expired, the process returns to step 112 to attempt further correlation. Otherwise, a decision is made based on conventional data correlation algorithms to check, if any data that could not be properly correlated have a probability of being correlated based on a predetermined threshold value, step 118. If correlation is satisfactory, these data are assigned to a corresponding target report and target track and send to the display 20 and/or transmitted or stored for further processing, step 120. Otherwise, such poorly correlated or un-correlated data are discarded, step 122. It should be understood that these processing steps represent one embodiment of steps for implementing variable dwell time processing, and other methods and systems are encompassed within the scope ofthe invention.
- the invention can be implemented in digital electronic circuitry, or in computer hardware, firmware, software, or in combinations of them.
- Apparatus ofthe invention can be implemented in a computer program product tangibly embodied in a machine-readable storage device for execution by a programmable processor; and method steps ofthe invention can be performed by a programmable processor executing a program of instructions to perform functions ofthe invention by operating on input data and generating output.
- the invention can advantageously be implemented in one or more computer programs that are executable on a programmable system including at least one programmable processor coupled to receive data and instructions from, and to transmit data and instructions to, a data storage system, at least one input device, and at least one output device.
- Each computer program can be implemented in a high-level procedural or object-oriented programming language, or in assembly or machine language if desired; and in any case, the language can be a compiled or interpreted language.
- Suitable processors include, by way of example, both general and special purpose microprocessors. Generally, a processor will receive instructions and data from a read-only memory and/or a random access memory.
- Storage devices suitable for tangibly embodying computer program instructions and data include all forms of nonvolatile memory, including by way of example semiconductor memory devices, such as EPROM, EEPROM, and flash memory devices; magnetic disks such as internal hard disks and removable disks; magneto-optical disks; and CD-ROM disks. Any ofthe foregoing can be supplemented by, or incorporated in, ASICs (application-specific integrated circuits).
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AU19066/00A AU1906600A (en) | 1998-10-30 | 1999-10-28 | Adaptive dwell timing for radar tracking |
EP99962667A EP1123516B1 (en) | 1998-10-30 | 1999-10-28 | Adaptive dwell timing for radar tracking |
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US10636498P | 1998-10-30 | 1998-10-30 | |
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US09/416,857 US6211810B1 (en) | 1998-10-30 | 1999-10-12 | Adaptive dwell timing for radar tracking |
US09/416,857 | 1999-10-12 |
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Cited By (2)
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Families Citing this family (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP1371999A1 (en) * | 2002-06-12 | 2003-12-17 | Oerlikon Contraves Ag | Method and system for tracking a target |
US8190162B2 (en) * | 2003-09-15 | 2012-05-29 | Broadcom Corporation | Radar detection circuit for a WLAN transceiver |
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EP2753952B1 (en) * | 2011-09-09 | 2020-02-26 | Accipiter Radar Technologies, INC. | Device and method for 3d sampling with avian radar |
CN105372659A (en) * | 2015-11-20 | 2016-03-02 | 上海无线电设备研究所 | Road traffic monitoring multi-target detection tracking method and tracking system |
US11074104B2 (en) * | 2019-04-09 | 2021-07-27 | International Business Machines Corporation | Quantum adaptive circuit dispatcher |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4489388A (en) * | 1980-10-29 | 1984-12-18 | Hollandse Signaalapparaten B.V. | Plot generator |
US5128683A (en) * | 1991-04-16 | 1992-07-07 | General Electric Company | Radar system with active array antenna, elevation-responsive PRF control, and beam multiplex control |
US5712785A (en) * | 1995-06-23 | 1998-01-27 | Northrop Grumman Corporation | Aircraft landing determination apparatus and method |
US5825322A (en) * | 1993-05-19 | 1998-10-20 | Alliedsignal Inc. | Method and apparatus for rotating an electronically-scanned radar beam employing a variable-dwell scanning process |
Family Cites Families (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3587054A (en) * | 1968-09-06 | 1971-06-22 | Bell Telephone Labor Inc | Scheme allowing real time alteration of a data processing system operating strategy |
US4143373A (en) * | 1977-09-21 | 1979-03-06 | Hughes Aircraft Company | Adaptive radar systems and methods therefor |
US4593286A (en) | 1983-04-25 | 1986-06-03 | Westinghouse Electric Corp. | Method of operating an agile beam coherent radar |
US4720711A (en) * | 1985-06-17 | 1988-01-19 | Westinghouse Electric Corp. | Agile-beam track-while-scan radar system |
US4814779A (en) | 1987-03-25 | 1989-03-21 | Itt Gilfillan, A Division Of Itt Corporation | Radar system with auxiliary scanning for more dwell time on target |
US5001650A (en) * | 1989-04-10 | 1991-03-19 | Hughes Aircraft Company | Method and apparatus for search and tracking |
WO1992017796A1 (en) * | 1991-03-28 | 1992-10-15 | The Commonwealth Of Australia | Radar control task scheduling |
-
1999
- 1999-10-12 US US09/416,857 patent/US6211810B1/en not_active Expired - Lifetime
- 1999-10-28 WO PCT/US1999/025449 patent/WO2000026690A1/en active Search and Examination
- 1999-10-28 AU AU19066/00A patent/AU1906600A/en not_active Abandoned
- 1999-10-28 EP EP99962667A patent/EP1123516B1/en not_active Expired - Lifetime
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4489388A (en) * | 1980-10-29 | 1984-12-18 | Hollandse Signaalapparaten B.V. | Plot generator |
US5128683A (en) * | 1991-04-16 | 1992-07-07 | General Electric Company | Radar system with active array antenna, elevation-responsive PRF control, and beam multiplex control |
US5825322A (en) * | 1993-05-19 | 1998-10-20 | Alliedsignal Inc. | Method and apparatus for rotating an electronically-scanned radar beam employing a variable-dwell scanning process |
US5712785A (en) * | 1995-06-23 | 1998-01-27 | Northrop Grumman Corporation | Aircraft landing determination apparatus and method |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2012087662A1 (en) * | 2010-12-20 | 2012-06-28 | Raytheon Company | Omni-directional antenna at a secondary surveillance radar |
RU191451U1 (en) * | 2019-04-04 | 2019-08-06 | Публичное акционерное общество "Научно-производственное объединение "Алмаз" имени академика А.А. Расплетина" (ПАО "НПО "Алмаз") | SYNCHRONIZER |
Also Published As
Publication number | Publication date |
---|---|
EP1123516B1 (en) | 2013-02-20 |
AU1906600A (en) | 2000-05-22 |
EP1123516A1 (en) | 2001-08-16 |
WO2000026690A9 (en) | 2000-10-12 |
US6211810B1 (en) | 2001-04-03 |
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