WO2012057655A1 - A radar station, featuring broadband, linear- frequency-modulated, continuous-wave emission - Google Patents
A radar station, featuring broadband, linear- frequency-modulated, continuous-wave emission Download PDFInfo
- Publication number
- WO2012057655A1 WO2012057655A1 PCT/RU2011/000797 RU2011000797W WO2012057655A1 WO 2012057655 A1 WO2012057655 A1 WO 2012057655A1 RU 2011000797 W RU2011000797 W RU 2011000797W WO 2012057655 A1 WO2012057655 A1 WO 2012057655A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- signal
- output
- input
- channel
- master controller
- Prior art date
Links
Classifications
-
- 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
- G01S7/35—Details of non-pulse systems
Definitions
- a radar station featuring broadband, linear-frequency-modulated, continuous-wave emission
- the invention relates to the area of active radiolocation and can be used in the design and development of digital broadband radar systems for river and marine navigation.
- the prior art includes the digital broadband marine radar by Lowrance (www.lowrance.com), designed for close observation of the space with high range resolution.
- a radar range finder is also known (P.A. Bakulev / Radar Systems / / Textbook for Universities / / Moscow Radio. 2004, 320 p., 111., p. 233-234).
- the known analogs are classified as radar systems with continuous linear-frequency-modulated (LFM) emission, in which the formation of the emitted and processing of the received signals are done digitally.
- LFM linear-frequency-modulated
- the principle of operation of such radar systems is based on the use of continuous LFM probing signals and homodyne processing of signals reflected from the objects located by the radar.
- the process of emission and reception of the reflected signal is combined in time and the information about the distance to a reflecting object and its reflectivity is contained in the spectrum of the beat signal. This signal is formed as the difference between the "instantaneous" frequencies of the emitted and reflected signals from the object.
- a disadvantage of prior art is the restriction on the energy potential, specifically on the power of continuous radiation, which narrows the scope of these devices when solving the problem of detecting objects with low reflectivity.
- broadening of the emitted signal spectrum in order to improve range resolution is limited by stray deviation of the directional diagram (DD) of narrow-beam linear antenna arrays with serially-fed elements.
- DD directional diagram
- the prior art also includes navigational radar "River”, selected by us as the prototype (Manual / ZhNKYu.464429.039 RE// CJSC Scientificand production company Micran, City of Tomsk), which includes a CPU, a display device, the angular position sensor, master controller, digital signal shaper, timing signal generator, a beat signal processing unit, correcting filter, and a transceiver module, which uses two antennas for transmitting and receiving of signals.
- the principle of operation of a radar this type is based on the use of continuous LFM probing signals and homodyne processing of signals reflected from the objects located by the radar.
- the process of emission and reception of the reflected signal is combined in time and the information about the distance to a reflecting object and its reflectivity is contained in the spectrum of the beat signal.
- This signal is formed as the difference between the "instantaneous" frequencies of the emitted and reflected signals from the object.
- the disadvantages of the known engineering solution include the difficulty of its factory adjustment in serial production. This difficulty is due to the fact that to achieve high range resolution requires a broad band of the emitted LFM signal. This, in turn, requires the use of broadband passive antenna arrays with few side lobes and a low deviation of the directional diagram during signal frequency adjustment. Serial production of such antennas requires individual tuning of every one of them, which leads to high level of expenditure for this type of work.
- the main engineering task solved by the proposed solution is aimed at simplifying the factory adjustment, thereby reducing the cost of the device in serial production.
- the engineering task also includes increasing the maximum capacity of the emitted signal, which will not hinder the operation of the radar station due to overloading the receiver channel, as well as expanding the dynamic range of amplitudes of reflected signals, while retaining radar performance.
- the radar featuring broadband, linear-frequency-modulated, continuous-wave emission, which includes a CPU, a display device, an angular position sensor, master controller, digital signal shaper, timing signal generator, a beat signal processing unit, correcting filter, and a transceiver module
- the input of the display device is connected to the first port of the CPU via a unidirectional interface
- the second port of the CPU is connected to the first port of the master controller via a bidirectional interface
- the output of the angular position sensor is connected to the second port of the master controller via a unidirectional interface
- the timing inputs of the master controller, the digital signal shaper, and the beat signal processing unit are combined and connected to the output of the timing signal generator
- the input of the digital signal shaper is connected to the third port of the master controller via a unidirectional interface
- the fourth port of the master controller is connected to the digital bus of the beat signal processing unit through a bidirectional interface
- the output of the correcting filter is connected to the
- the main engineering task is overcome in the proposed solution by spatial parallelizing of the process that shapes the emitted and received reflected broadband LFM signal. This increases the maximum allowable power of the emitted signal without disrupting the radar operation due to receiver channel overload.
- FIG. 1 shows the functional diagram of the proposed continuous broadband LFM radar.
- the device contains a CPU 1 with two ports, display device 2, angular position sensor 3, master controller 4 with five ports, digital signal shaper 5, timer signal generator 6, beat signal processing unit 7, correcting filter 8, m-channel radio signal adder 9, m-channel radio signal splitter 10, m transceiver modules 11, containing a receiving and a transmission channel, and a two-channel signal splitter 12.
- Output of the timer signal generator 6 is connected with the timer inputs of the master controller 4, of the digital signal shaper 5 and of the beat signal processing unit 7, the input of the display unit 2 is connected to the first port of CPU 1 via a unidirectional interface, the second port of the CPU 1 is connected to the first port of master controller 4 through a bi-directional interface.
- Output of the angular position sensor 3 is connected to the second port of master controller 4 via a one-way interface
- input of the digital signal shaper 5 is connected with the third port of the master controller 4 via a one-way interface
- the digital port of beat signal processing unit 7 is connected to with the fourth port of master controller 4 via a bidirectional interface.
- Outputs of m transceiver modules 11 are connected to the inputs of m-channel radio signal adder 9, and the inputs of the two-channel signal splitters 12 of each of the m transceiver modules 11 are connected to the outputs of m-channel radio signal splitter 10.
- Output of the m-channel radio signal adder 9 is connected to the input of the correcting filter 8 whose output is connected to the analog input of the beat signal processing unit 7.
- Control buses of m transceiver modules 11 are combined into a one-way serial data bus, connected to the fifth port of master controller 4.
- the receiving channel of each of the m transceiver modules 11 are comprised of adjustable phase shifter 13, signal frequency multiplier 14, first bandpass filter 15 and amplifier 16, and mixer 17, connected in series, and the second bandpass filter 18, LNA 19 and the receiving antenna element 20, and adjustable attenuator 21 connected in series, while the output of amplifier 16 is connected to the reference input of mixer 17, the input of the adjustable phase shifter 13 is connected to the first output of the two-channel signal splitter 12, the output of the second bandpass filter 18 is connected to the signal input of mixer 17, the output of the receiving antenna element 20 is connected to the input of LNA 19, and the output of mixer 17 is connected to the input of the adjustable attenuator 21.
- the transmitting channel of each of the m transceiver modules 11 m is comprised of the first adjustable phase shifter 22, the first radio frequency multiplier 23, the third bandpass filter 24, the first adjustable attenuator 25 and the first power amplifier 26, and the transmitting antenna element 27 connected in series, while the input of the transmitting antenna element 27 is connected to the output of the first amplifier 26 and the input of the first adjustable phase shifter 22 is connected to the second output of the two- channels signal splitter 12.
- Control buses of the adjustable phase shifter 13 and the first adjustable phase shifter 22, of the adjustable attenuator 21 and the first adjustable attenuator 25 are combined into a one-way serial data bus, which is the master bus of the transceiver module 11.
- Output of the adjustable attenuator 21 is the output of the transceiver module 11.
- the antenna system of the proposed engineering solutions is formed by two identical m-channel arrays, one receiving and one transmitting, each being a linear, single-antenna array consisting of m receiving and m transmitting antenna elements, 20 and 27, respectively. These elements are part of transceiver modules 11, each being functionally divided into receiving and transmitting channels. Structurally, the transceiver modules 11 are designed so that under a particular spatial arrangement, the receiving and transmitting antenna elements 20 and 27 form two identical linear arrays, a receiving and a transmitting, respectively, with their aperture lines being parallel and separated by some vertical distance.
- the proposed radar with continuous broadband LFM signal operates as follows.
- digital signal shaper 5 Upon command of the master controller 4, digital signal shaper 5 generates an intermediate frequency, continuous, recurrent LFM signal with a bandwidth of ⁇ .
- This signal is fed to the input of the m-channel signal splitter 10 and from its outputs - to the inputs of the two-channel signal splitter 12 of each of the m transceiver modules 1 1.
- the signal is fed to the first adjustable phase shifter 22, its frequency is multiplied n times by the first signal frequency multiplier 23 and is filtered by the third bandpass filter 24.
- the LFM signal When the LFM signal is multiplied n times, its spectrum expands by a factor of n and it is equal to:
- the output signal from the third bandpass filter 24 goes to the first adjustable attenuator 25, is amplified by the first power amplifier 26, and is emitted into space by the transmitting antenna element 27.
- each of the m transmitting antenna elements 27 of the transceiver module 11 emits a periodically repeated LFM signal with the bandwidth of:
- ACO c ⁇ ⁇ ⁇ in this case, the relative phases and amplitudes ⁇ * of LFM signals of the z ' -th transmitting element of antenna 27 are set in the required manner by independent adjustment of the first adjustable phase shifters 22 and the first adjustable attenuators 25 of each of the m transceiver modules 1 1.
- all transmitting antenna elements 27 must transmit in phase, with the axis of the main DD lobe must be perpendicular to the aperture line of the transmitting antenna array. This is achieved by controlling the first adjustable phase shifters 22 when tuning the radar.
- the relative amplitude of the signal emitted by the z-th transmitting antenna element 27 must match the field distribution along the aperture of the transmitting antenna array, selected during the design phase. This is achieved by controlling by means of the first adjustable attenuator 25 when tuning the radar.
- the lengths of the electrical signal paths for each of the m channels from the outputs of the m-channel signal splitter 10 to the input of the two-channels signal splitter 12 should be matched to within a wavelength of the emitted signal.
- the DD of the transmitting antenna array has one global maximum and side lobes, whose level is considerably lower than the global maximum (typically by 25-30 dB).
- the side-lobe level is determined by the amplitude distribution of the field along the aperture of the receiving and transmitting antenna arrays, selected during the design phase.
- the LFM signal reflected from objects located in the main lobe of the DD of the transmitting antenna array is received by each of the m receiving antenna elements 20 of the receiving antenna array.
- the output signal of the receiving antenna element 20 of the i-th transceiver module 11 is amplified by the low-noise amplifier (LNA) 19, is filtered by the second bandpass filter 18 with a bandwidth of:
- LNA low-noise amplifier
- the reference input of mixer 17 receives the amplified signal from the output of the power amplifier 16.
- the input signal to power amplifier 16 is the output signal from the first two- channel signal splitter 12, having passed through adjustable phase shifter 13, though the n-times multiplier of the signal frequency 14, and through the first bandpass filter 15 with a bandwidth of:
- Both the reference signal of mixer 17 and the radio signal reflected from an individual "point" object have identical time-and-frequency structure, namely, are LFM signals with a rectangular envelope, and a mutual time shift defined by the distance to the object from which came the reflected signal.
- a video signal (beat signal) whose spectrum clearly displays the distance to objects and their effective radar cross-section (RCS)
- RCS radar cross-section
- the output beat signals of all of m transceiver modules 1 1 develop in phase.
- the DD of the receiver antenna array formed by m receiving antenna elements 20, is identical to the DD of the transmitting antenna array.
- the DD of the receiving antenna array does not depend on the signal frequency, that is, it shows no stray deviation of the main lobe wit signal frequency changes within the operating range.
- the absence of frequency dependence is due to the fact that the lengths of the electrical signal paths for each of the m channels from the m-channel signal splitter 10 to the input of the two-channel radio signal splitter 12 are matched up within a wavelength of the emitted signal during the signal routing design phase.
- Equality of the arguments of complex transmission coefficients for the receiving channels of transceiver modules 11 is achieved by controlling the adjustable phase shifters 13 in the process of radar tuning.
- the required absolute values of transmission coefficients for the receiving channels of transceiver modules 11 are obtained by independent adjustment of the adjustable attenuators 21 in the process of radar tuning.
- a beat signal is formed at the output of m-channel radio signal adder 9.
- the video output of the m-channel radio signal adder 9 is filtered by correcting filter 8, which reduces low- frequency signals, and is fed from the output of the correcting filter 8 to the beat signal processing unit 7, where Fourier transform is made of the beat signal for each "sweep" (period of modulation) of the emitted LFM signal.
- the Fourier transform maps the distance to the objects in the radar's field of vision and the level of reflected signals, proportional to the RCS of those objects.
- Fourier transforms for each "sweep" of the LFM signal are fed by the master controller 4 to the central processor in digital form.
- the central processor generates a video signal for the display device 2, where the radar image is actually formed.
- Each Fourier transform is displayed as a brightness line extending from the center of the radar image.
- the azimuthal direction of the line extending from the center of the image coincides with the azimuthal direction of the DD axis of the receiving and transmitting antenna.
- Information about the angular position of the DD axis of the antennas at the moment of emitting the LFM signal is sent to the master controller 4 from the antenna azimuth angle position sensor 3 and is transmitted to the central processor 1.
- Brightness of each point on the line is proportional to the RCS of the object; its distance from the center of the image is proportional to the distance of the object from the radar antenna location. Operation of all modules in the unit is synchronized by signals from the timer signal generator 6.
- the maximum emission power of a radar with continuous broadband LFM emission which will not overload the receiving path as compared with the prototype device, can be increased by a factor of m, which will increase the range of the radar station with continuous
- ⁇ s j m times lower than that of the prototype device, which is another positive feature of the claimed radar, because it allows to increase the frequency multiplication factor n in the signal frequency multiplier 14 and in the first signal frequency multiplier 23, while maintaining equivalent noise emission levels.
- This may have fundamental significance in increasing the operating frequency of the radar, such as from 9430 MHz at 33 GHz (river radar operating ranges), and while expanding the emitted signal bandwidth.
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Radar Systems Or Details Thereof (AREA)
- Transceivers (AREA)
Abstract
The invention relates to the area of active radiolocation and can be used in the design and development of digital broadband radar systems for river and marine navigation. The engineering task of this invention is aimed at simplifying the factory adjustment, thereby reducing the cost of the device in serial production. In addition, the engineering task also includes increasing the maximum permitted power of the emitted signal, which will not hinder the operation of the radar station due to overloading the receiver channel, as well as expanding the dynamic range of amplitudes of reflected signals, while retaining radar performance. The device contains a CPU with two ports, a display device, an angular position sensor, a master controller with five ports, a digital signal shaper, a timer signal generator, a beat signal processing unit, a correction filter, an m-channel radio signal adder, an m-channel radio signal splitter, mm transceiver modules containing a receiving and a transmission channel, and a two-channel signal splitter.
Description
A radar station, featuring broadband, linear-frequency-modulated, continuous-wave emission
The invention relates to the area of active radiolocation and can be used in the design and development of digital broadband radar systems for river and marine navigation.
The prior art includes the digital broadband marine radar by Lowrance (www.lowrance.com), designed for close observation of the space with high range resolution.
A radar range finder is also known (P.A. Bakulev / Radar Systems / / Textbook for Universities / / Moscow Radio. 2004, 320 p., 111., p. 233-234).
The known analogs are classified as radar systems with continuous linear-frequency-modulated (LFM) emission, in which the formation of the emitted and processing of the received signals are done digitally. The principle of operation of such radar systems is based on the use of continuous LFM probing signals and homodyne processing of signals reflected from the objects located by the radar. Here, the process of emission and reception of the reflected signal is combined in time and the information about the distance to a reflecting object and its reflectivity is contained in the spectrum of the beat signal. This signal is formed as the difference between the "instantaneous" frequencies of the emitted and reflected signals from the object.
A disadvantage of prior art is the restriction on the energy potential, specifically on the power of continuous radiation, which narrows the scope of these devices when solving the problem of detecting objects with low reflectivity. In addition, when using them in river survey radars, broadening of the emitted signal spectrum in order to improve range resolution is limited by stray deviation of the directional diagram (DD) of narrow-beam linear antenna arrays with serially-fed elements. Technical implementation of antennas for river survey radar applications is costly for serial production and the use of such antennas is limited because of their high cost.
The prior art also includes navigational radar "River", selected by us as the prototype (Manual / ZhNKYu.464429.039 RE// CJSC Scientificand production company Micran, City of Tomsk), which includes a CPU, a display device, the angular position sensor, master controller, digital signal shaper, timing signal generator, a beat signal processing unit, correcting filter, and a transceiver module, which uses two antennas for transmitting and receiving of signals. The principle of operation of a radar this type is based on the use of continuous LFM probing signals and homodyne processing of signals reflected from the objects located by the radar. Here, the process of emission and reception of the reflected signal is combined in time and the information about the distance to a reflecting object and its reflectivity is contained in the spectrum of the beat signal. This signal is formed as the difference between the "instantaneous" frequencies of the emitted and reflected signals from the object.
The disadvantages of the known engineering solution include the difficulty of its factory adjustment in serial production. This difficulty is due to the fact that to achieve high range resolution requires a broad band of the emitted LFM signal. This, in turn, requires the use of broadband passive antenna arrays with few side lobes and a low deviation of the directional diagram during signal frequency adjustment. Serial production of such antennas requires individual tuning of every one of them, which leads to high level of expenditure for this type of work.
The main engineering task solved by the proposed solution is aimed at simplifying the factory adjustment, thereby reducing the cost of the device in serial production. In addition, the engineering task also includes increasing the maximum capacity of the emitted signal, which will not hinder the operation of the radar station due to overloading the receiver channel, as well as expanding the dynamic range of amplitudes of reflected signals, while retaining radar performance.
The stated engineering task is achieved by that, under the proposed solution, the radar, featuring broadband, linear-frequency-modulated, continuous-wave emission, which includes a CPU, a display device, an angular position sensor, master controller, digital signal shaper, timing signal generator, a beat signal processing unit, correcting filter, and a transceiver module, wherein the input of the display device is connected to the first port of the CPU via a unidirectional interface, the second port of the CPU is connected to the first port of the master controller via a bidirectional interface, the output of the angular position sensor is connected to the second port of the master controller via a unidirectional interface, the timing inputs of the master controller, the digital signal shaper, and the beat signal processing unit are combined and connected to the output of the timing signal generator, the input of the digital signal shaper is connected to the third port of the master controller via a unidirectional interface, the fourth port of the master controller is connected to the digital bus of the beat signal processing unit through a bidirectional interface, and the output of the correcting filter is connected to the input of the beat signal processing unit, additionally includes m-1 transceiver modules, an m-channel radio signal adder, m-channel radio signal splitter, wherein the outputs of m transceiver modules are respectively connected to the inputs of m-channel radio signal adder, the inputs of m transceiver modules are respectively connected with the m-channel output signal splitter, and the control buses of the transceiver modules are combined and connected to the fifth port of the master controller, the output of the m- channel adder is connected to the correcting filter input, the input of the m- channel signal splitter is connected to the output of the digital signal shaper, while the transceiver module includes a receiver, a transmitter, and a two- channel signal splitter, whose input is the input of the transceiver module, while the receiver is comprised of an adjustable phase shifter, a radio frequency multiplier, a first bandpass filter and power amplifier, and a mixer
connected in series, a second bandpass filter and low-noise amplifier connected in series, a receiver antenna element, and an adjustable attenuator, while the power amplifier output is connected to the reference input of the mixer, the output of the second bandpass filter is connected to the signal input of the mixer, the output of the receiving antenna element is connected to the input of the LNA, the input of the adjustable phase shifter is connected to the first output of the two-channel signal splitter, the output of the mixer is connected to the adjustable attenuator, whose output is the output of transceiver module and the transmitter part of the transceiver module consists of the first adjustable phase shifter, the first radio frequency multiplier, the third bandpass filter, the first adjustable attenuator, the first power amplifier and transmitting antenna element, all connected in series, while the input of the first adjustable phase shifter is connected to the second output of the two- channels signal splitter, and the output of the first power amplifier is connected to the input of the transmitting antenna element, the control buses of the adjustable attenuator, of the first adjustable attenuator, of the adjustable phase shifter, and of the first adjustable phase shifter of the transmitter and receiver are combined into a serial data bus, which is controlled by the transceiver module control bus.
Thus, the main engineering task is overcome in the proposed solution by spatial parallelizing of the process that shapes the emitted and received reflected broadband LFM signal. This increases the maximum allowable power of the emitted signal without disrupting the radar operation due to receiver channel overload.
The invention is illustrated by the FIG. 1, which shows the functional diagram of the proposed continuous broadband LFM radar.
The device contains a CPU 1 with two ports, display device 2, angular position sensor 3, master controller 4 with five ports, digital signal shaper 5, timer signal generator 6, beat signal processing unit 7, correcting filter 8,
m-channel radio signal adder 9, m-channel radio signal splitter 10, m transceiver modules 11, containing a receiving and a transmission channel, and a two-channel signal splitter 12. Output of the timer signal generator 6 is connected with the timer inputs of the master controller 4, of the digital signal shaper 5 and of the beat signal processing unit 7, the input of the display unit 2 is connected to the first port of CPU 1 via a unidirectional interface, the second port of the CPU 1 is connected to the first port of master controller 4 through a bi-directional interface. Output of the angular position sensor 3 is connected to the second port of master controller 4 via a one-way interface, input of the digital signal shaper 5 is connected with the third port of the master controller 4 via a one-way interface, the digital port of beat signal processing unit 7 is connected to with the fourth port of master controller 4 via a bidirectional interface. Outputs of m transceiver modules 11 are connected to the inputs of m-channel radio signal adder 9, and the inputs of the two-channel signal splitters 12 of each of the m transceiver modules 11 are connected to the outputs of m-channel radio signal splitter 10. Output of the m-channel radio signal adder 9 is connected to the input of the correcting filter 8 whose output is connected to the analog input of the beat signal processing unit 7. Control buses of m transceiver modules 11 are combined into a one-way serial data bus, connected to the fifth port of master controller 4.
The receiving channel of each of the m transceiver modules 11 are comprised of adjustable phase shifter 13, signal frequency multiplier 14, first bandpass filter 15 and amplifier 16, and mixer 17, connected in series, and the second bandpass filter 18, LNA 19 and the receiving antenna element 20, and adjustable attenuator 21 connected in series, while the output of amplifier 16 is connected to the reference input of mixer 17, the input of the adjustable phase shifter 13 is connected to the first output of the two-channel signal splitter 12, the output of the second bandpass filter 18 is connected to the signal input of mixer 17, the output of the receiving antenna element 20 is connected to the
input of LNA 19, and the output of mixer 17 is connected to the input of the adjustable attenuator 21.
The transmitting channel of each of the m transceiver modules 11 m is comprised of the first adjustable phase shifter 22, the first radio frequency multiplier 23, the third bandpass filter 24, the first adjustable attenuator 25 and the first power amplifier 26, and the transmitting antenna element 27 connected in series, while the input of the transmitting antenna element 27 is connected to the output of the first amplifier 26 and the input of the first adjustable phase shifter 22 is connected to the second output of the two- channels signal splitter 12.
Control buses of the adjustable phase shifter 13 and the first adjustable phase shifter 22, of the adjustable attenuator 21 and the first adjustable attenuator 25 are combined into a one-way serial data bus, which is the master bus of the transceiver module 11. Output of the adjustable attenuator 21 is the output of the transceiver module 11.
The antenna system of the proposed engineering solutions is formed by two identical m-channel arrays, one receiving and one transmitting, each being a linear, single-antenna array consisting of m receiving and m transmitting antenna elements, 20 and 27, respectively. These elements are part of transceiver modules 11, each being functionally divided into receiving and transmitting channels. Structurally, the transceiver modules 11 are designed so that under a particular spatial arrangement, the receiving and transmitting antenna elements 20 and 27 form two identical linear arrays, a receiving and a transmitting, respectively, with their aperture lines being parallel and separated by some vertical distance.
The proposed radar with continuous broadband LFM signal operates as follows. Upon command of the master controller 4, digital signal shaper 5 generates an intermediate frequency, continuous, recurrent LFM signal with a bandwidth of Αω . This signal is fed to the input of the m-channel signal
splitter 10 and from its outputs - to the inputs of the two-channel signal splitter 12 of each of the m transceiver modules 1 1. From the second output of the two-channel signal splitter 12, the signal is fed to the first adjustable phase shifter 22, its frequency is multiplied n times by the first signal frequency multiplier 23 and is filtered by the third bandpass filter 24. When the LFM signal is multiplied n times, its spectrum expands by a factor of n and it is equal to:
AO)c = η · Αω therefore, the bandwidth of the third bandpass filter 24 equals to:
ΑωΠΦ = A(oc = n · Αω
The output signal from the third bandpass filter 24 goes to the first adjustable attenuator 25, is amplified by the first power amplifier 26, and is emitted into space by the transmitting antenna element 27. Thus, each of the m transmitting antenna elements 27 of the transceiver module 11 emits a periodically repeated LFM signal with the bandwidth of:
ACOc = η · Αω in this case, the relative phases and amplitudes α* of LFM signals of the z'-th transmitting element of antenna 27 are set in the required manner by independent adjustment of the first adjustable phase shifters 22 and the first adjustable attenuators 25 of each of the m transceiver modules 1 1.
To achieve the minimum side-lobe level in the directional diagram of the transmitting antenna array, all transmitting antenna elements 27 must transmit in phase, with the axis of the main DD lobe must be perpendicular to the aperture line of the transmitting antenna array. This is achieved by controlling the first adjustable phase shifters 22 when tuning the radar. The relative amplitude of the signal emitted by the z-th transmitting antenna element 27 must match the field distribution along the aperture of the transmitting antenna array, selected during the design phase. This is achieved by controlling by
means of the first adjustable attenuator 25 when tuning the radar. To assure that the DD of the transmitting antenna array develops no parasitic deviation during changes in signal frequency, the lengths of the electrical signal paths for each of the m channels from the outputs of the m-channel signal splitter 10 to the input of the two-channels signal splitter 12 should be matched to within a wavelength of the emitted signal.
Under the above conditions, the DD of the transmitting antenna array has one global maximum and side lobes, whose level is considerably lower than the global maximum (typically by 25-30 dB). As mentioned above, the side-lobe level is determined by the amplitude distribution of the field along the aperture of the receiving and transmitting antenna arrays, selected during the design phase.
The LFM signal reflected from objects located in the main lobe of the DD of the transmitting antenna array is received by each of the m receiving antenna elements 20 of the receiving antenna array. The output signal of the receiving antenna element 20 of the i-th transceiver module 11 is amplified by the low-noise amplifier (LNA) 19, is filtered by the second bandpass filter 18 with a bandwidth of:
Aa>c - η · Αω
and enters the signal input of the mixer 17. The reference input of mixer 17 receives the amplified signal from the output of the power amplifier 16. The input signal to power amplifier 16 is the output signal from the first two- channel signal splitter 12, having passed through adjustable phase shifter 13, though the n-times multiplier of the signal frequency 14, and through the first bandpass filter 15 with a bandwidth of:
ACOc = n · Aco
Both the reference signal of mixer 17 and the radio signal reflected from an individual "point" object have identical time-and-frequency structure, namely, are LFM signals with a rectangular envelope, and a mutual time shift
defined by the distance to the object from which came the reflected signal. In view of this, a video signal (beat signal) whose spectrum clearly displays the distance to objects and their effective radar cross-section (RCS), is formed on the output of mixer 17 of each of the m transceiver modules 1 l .In each of the m transceiver modules 11, the output signal of mixer 17 is fed to the input of the adjustable attenuator 21 and from its output goes to the appropriate input of the m-channel radio signal adder 9. If the arguments of the complex coefficients of signal transmission from the output of the receiving antenna elements 20 to the input of the m-channel radio signal adder 9 are equal and their absolute values are proportional to the amplitudinal field distribution along the aperture of the transmitting antenna, then the output beat signals of all of m transceiver modules 1 1 develop in phase. In this case, the DD of the receiver antenna array, formed by m receiving antenna elements 20, is identical to the DD of the transmitting antenna array. Just as with the transmitting antenna array, the DD of the receiving antenna array does not depend on the signal frequency, that is, it shows no stray deviation of the main lobe wit signal frequency changes within the operating range. The absence of frequency dependence is due to the fact that the lengths of the electrical signal paths for each of the m channels from the m-channel signal splitter 10 to the input of the two-channel radio signal splitter 12 are matched up within a wavelength of the emitted signal during the signal routing design phase. Equality of the arguments of complex transmission coefficients for the receiving channels of transceiver modules 11 is achieved by controlling the adjustable phase shifters 13 in the process of radar tuning. The required absolute values of transmission coefficients for the receiving channels of transceiver modules 11 are obtained by independent adjustment of the adjustable attenuators 21 in the process of radar tuning.
Thus, when the above conditions are met, a beat signal is formed at the output of m-channel radio signal adder 9. The video output of the m-channel
radio signal adder 9 is filtered by correcting filter 8, which reduces low- frequency signals, and is fed from the output of the correcting filter 8 to the beat signal processing unit 7, where Fourier transform is made of the beat signal for each "sweep" (period of modulation) of the emitted LFM signal. The Fourier transform maps the distance to the objects in the radar's field of vision and the level of reflected signals, proportional to the RCS of those objects. Fourier transforms for each "sweep" of the LFM signal are fed by the master controller 4 to the central processor in digital form. The central processor generates a video signal for the display device 2, where the radar image is actually formed. Each Fourier transform is displayed as a brightness line extending from the center of the radar image. The azimuthal direction of the line extending from the center of the image coincides with the azimuthal direction of the DD axis of the receiving and transmitting antenna. Information about the angular position of the DD axis of the antennas at the moment of emitting the LFM signal is sent to the master controller 4 from the antenna azimuth angle position sensor 3 and is transmitted to the central processor 1. Brightness of each point on the line is proportional to the RCS of the object; its distance from the center of the image is proportional to the distance of the object from the radar antenna location. Operation of all modules in the unit is synchronized by signals from the timer signal generator 6.
Independent software-level control of the adjustable phase shifter 13 and the first adjustable phase shifter 22, of the adjustable attenuator 21 and the first adjustable attenuator 25, allows fully automatic tuning of the claimed radar, which drastically reduces production costs for mass production of radar systems.
Also, due to the fact that the signal emission and reception process is parallelized in space into m channels, the maximum emission power of a radar with continuous broadband LFM emission, which will not overload the
receiving path as compared with the prototype device, can be increased by a factor of m, which will increase the range of the radar station with continuous
4/~
broadband LFM emission by a factor of ^m (in accordance with the basic equation of radiolocation).
As the noises produced by frequency multiplier 14 and by the first radio signal frequency multiplier 23 in the channels of transceiver modules 1 1 are independent of each other, the overall emission noise factor of the radar station i!~
{s j m times lower than that of the prototype device, which is another positive feature of the claimed radar, because it allows to increase the frequency multiplication factor n in the signal frequency multiplier 14 and in the first signal frequency multiplier 23, while maintaining equivalent noise emission levels. This may have fundamental significance in increasing the operating frequency of the radar, such as from 9430 MHz at 33 GHz (river radar operating ranges), and while expanding the emitted signal bandwidth.
Claims
Claims
A radar station, featuring broadband, linear-frequency-modulated, continuous-wave emission, which includes a CPU, a display device, an angular position sensor, master controller, digital signal shaper, timing signal generator, a beat signal processing unit, a correction filter, and a transceiver module, wherein the input of the display device is connected to the first port of the CPU via a unidirectional interface, the second port of the CPU is connected to the first port of the master controller via a bidirectional interface, the output of the angular position sensor is connected to the second port of the master controller via a unidirectional interface, the timing inputs of the master controller, the digital signal shaper, and the beat signal processing unit are combined and connected to the output of the timing signal generator, the input of the digital signal shaper is connected to the third port of the master controller via a unidirectional interface, the fourth port of the master controller is connected to the digital bus of the beat signal processing unit through a bidirectional interface, and the output of the correction filter is connected to the input of the beat signal processing unit, characterized in that it also includes m-1 transceiver modules, an m-channel radio signal adder, m-channel radio signal splitter, wherein the outputs of m transceiver modules are respectively connected to the inputs of m-channel radio signal adder, the inputs of m transceiver modules are respectively connected with the m-channel output signal splitter, and the control buses of the transceiver modules are combined and connected to the fifth port of the master controller, the output of the m- channel adder is connected to the correction filter input, the input of the m- channel signal splitter is connected to the output of digital signal shaper, while the transceiver module includes a receiver, a transmitter, and a two-channel signal splitter, whose input is the input of the transceiver module, while the receiver is comprised of an adjustable phase shifter, a radio frequency multiplier, a first bandpass filter and power amplifier,
and a mixer connected in series, and a second bandpass filter and low-noise amplifier connected in series, a receiver antenna element, and an adjustable attenuator, while the power amplifier output is connected to the reference input of the mixer, the output of the second bandpass filter is connected to the signal input of the mixer, the output of the receiving antenna element is connected to the input of the LNA, the input of the adjustable phase shifter is connected to the first output of the two-channel signal splitter, the output of the mixer is connected to the adjustable attenuator, whose output is the output of transceiver module and the transmitter part of the transceiver module consists of the first adjustable phase shifter, the first radio frequency multiplier, the third bandpass filter, the first adjustable attenuator, the first power amplifier and transmitting antenna element, all connected in series, while the input of the first adjustable phase shifter is connected to the second output of the two-channels signal splitter, and the output of the first power amplifier is connected to the input of the transmitting antenna element, the control buses of the adjustable attenuator, of the first adjustable attenuator, of the adjustable phase shifter, and of the first adjustable phase shifter of the transmitter and receiver are combined into a serial data bus, which is controlled by the transceiver module control bus.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201180052012.3A CN103282791B (en) | 2010-10-28 | 2011-10-12 | A radar station, featuring broadband, linear-frequency-modulated, continuous-wave emission |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| RU2010144200/07A RU2460087C2 (en) | 2010-10-28 | 2010-10-28 | Radar station with wideband continuous linearly frequency-modulated radiation |
| RU2010144200 | 2010-10-28 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| WO2012057655A1 true WO2012057655A1 (en) | 2012-05-03 |
Family
ID=45994154
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| PCT/RU2011/000797 WO2012057655A1 (en) | 2010-10-28 | 2011-10-12 | A radar station, featuring broadband, linear- frequency-modulated, continuous-wave emission |
Country Status (3)
| Country | Link |
|---|---|
| CN (1) | CN103282791B (en) |
| RU (1) | RU2460087C2 (en) |
| WO (1) | WO2012057655A1 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9106789B1 (en) * | 2012-01-20 | 2015-08-11 | Tech Friends, Inc. | Videoconference and video visitation security |
| CN109101348A (en) * | 2018-08-07 | 2018-12-28 | 武汉滨湖电子有限责任公司 | A kind of Radar Signal Processing cluster platform and software convenient for extension implementation method |
| CN114814813A (en) * | 2022-04-15 | 2022-07-29 | 中国人民解放军国防科技大学 | Broadband radar external radiation source signal positioning method based on uniform circular array |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105022033B (en) * | 2015-06-26 | 2018-01-05 | 李广柱 | Radar installations and control method |
| RU2654215C1 (en) * | 2017-08-07 | 2018-05-17 | ООО предприятие "КОНТАКТ-1" | Method of measuring distance by range finder with frequency modulation |
| UA116610C2 (en) * | 2017-11-30 | 2018-04-10 | Товариство З Обмеженою Відповідальністю Науково-Виробничий Комплекс Скб "Таргет" | RADIATION SOURCE IDENTIFICATION COMPLEX |
| RU2687286C1 (en) * | 2018-03-14 | 2019-05-13 | Федеральное государственное бюджетное образовательное учреждение высшего образования "Томский государственный университет систем управления и радиоэлектроники" | Continuous-wave radar transmitter with extended dynamic range |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7196657B2 (en) * | 2003-01-31 | 2007-03-27 | The Ohio State University | Radar system using RF noise |
| RU76464U1 (en) * | 2008-06-04 | 2008-09-20 | Открытое акционерное общество "Концерн "Гранит-Электрон" | SHIP RADAR COMPLEX |
| US7430258B2 (en) * | 2004-12-29 | 2008-09-30 | Syracuse Research Corporation | Architecture for multi-channel digital signal processing |
| RU2367975C1 (en) * | 2007-12-20 | 2009-09-20 | Виктор Леонидович Семенов | Method for detection of moments of projectile flying over beginning and end of available interval of distance, rls for measurement of projectile initial speed |
| RU2008125962A (en) * | 2008-06-25 | 2009-12-27 | Закрытое акционерное общество "Научно-производственная фирма "Микран" (RU) | METHOD FOR RADAR SURVEILLANCE USING CONTINUOUS RADIATION AND DEVICE FOR ITS IMPLEMENTATION |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU5262U1 (en) * | 1996-08-20 | 1997-10-16 | Центральный научно-исследовательский институт "Гранит" | RADAR STATION |
| CN1210577C (en) * | 2001-01-23 | 2005-07-13 | 白金情报通信株式会社 | Control method of wide-band radar detector and its equipment |
| EP1843170A1 (en) * | 2005-01-28 | 2007-10-10 | Anritsu Corporation | Uwb short pulse radar |
| CN100538394C (en) * | 2007-04-06 | 2009-09-09 | 清华大学 | A kind of wideband radar and formation method thereof that adopts the multi-sending and multi-receiving frequency division signal |
| CN101452073B (en) * | 2007-11-30 | 2011-12-28 | 清华大学 | Broadband signal synthesizing method based on multi-sending and multi-receiving frequency division radar |
| RU2392852C2 (en) * | 2008-02-19 | 2010-06-27 | Закрытое Акционерное Общество "Нанопульс" | Impulse superbroadband sensor of remote breath and heartbeat monitoring |
-
2010
- 2010-10-28 RU RU2010144200/07A patent/RU2460087C2/en active
-
2011
- 2011-10-12 WO PCT/RU2011/000797 patent/WO2012057655A1/en active Application Filing
- 2011-10-12 CN CN201180052012.3A patent/CN103282791B/en not_active Expired - Fee Related
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7196657B2 (en) * | 2003-01-31 | 2007-03-27 | The Ohio State University | Radar system using RF noise |
| US7430258B2 (en) * | 2004-12-29 | 2008-09-30 | Syracuse Research Corporation | Architecture for multi-channel digital signal processing |
| RU2367975C1 (en) * | 2007-12-20 | 2009-09-20 | Виктор Леонидович Семенов | Method for detection of moments of projectile flying over beginning and end of available interval of distance, rls for measurement of projectile initial speed |
| RU76464U1 (en) * | 2008-06-04 | 2008-09-20 | Открытое акционерное общество "Концерн "Гранит-Электрон" | SHIP RADAR COMPLEX |
| RU2008125962A (en) * | 2008-06-25 | 2009-12-27 | Закрытое акционерное общество "Научно-производственная фирма "Микран" (RU) | METHOD FOR RADAR SURVEILLANCE USING CONTINUOUS RADIATION AND DEVICE FOR ITS IMPLEMENTATION |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9106789B1 (en) * | 2012-01-20 | 2015-08-11 | Tech Friends, Inc. | Videoconference and video visitation security |
| CN109101348A (en) * | 2018-08-07 | 2018-12-28 | 武汉滨湖电子有限责任公司 | A kind of Radar Signal Processing cluster platform and software convenient for extension implementation method |
| CN114814813A (en) * | 2022-04-15 | 2022-07-29 | 中国人民解放军国防科技大学 | Broadband radar external radiation source signal positioning method based on uniform circular array |
Also Published As
| Publication number | Publication date |
|---|---|
| RU2010144200A (en) | 2012-05-10 |
| CN103282791A (en) | 2013-09-04 |
| RU2460087C2 (en) | 2012-08-27 |
| CN103282791B (en) | 2015-01-07 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| USRE49619E1 (en) | Radar device | |
| US10890652B2 (en) | Radar apparatus | |
| US10852407B2 (en) | Imaging radar sensor with narrow antenna lobe and wide angle-detection range | |
| WO2012057655A1 (en) | A radar station, featuring broadband, linear- frequency-modulated, continuous-wave emission | |
| US8009080B2 (en) | Weather radar and weather observation method | |
| US10557933B2 (en) | Radar device and position-determination method | |
| JP4737165B2 (en) | Radar target detection method and radar apparatus using the target detection method | |
| JP5763684B2 (en) | Radar sensor | |
| US20140306840A1 (en) | Imaging radar sensor with synthetic enlargement of the antenna aperture and two-dimensional beam sweep | |
| US20160146932A1 (en) | Method and Apparatus for Increasing Angular Resolution in an Automotive Radar System | |
| US11870138B2 (en) | MIMO radar sensor for motor vehicles | |
| US20110309981A1 (en) | Combined direction finder and radar system, method and computer program product | |
| US11435435B2 (en) | Radar device | |
| US20040160364A1 (en) | Digital instantaneous direction finding system | |
| US20210349201A1 (en) | 360° mimo radar system having multiple radar sensors and phase calibration via over-lapping virtual tx and rx antennas of adjacent radar sensors | |
| US4558594A (en) | Phased array acoustic antenna | |
| GB1434638A (en) | Radio direction finding equipment | |
| US20220003834A1 (en) | Radar device and transmitting/receiving array antenna | |
| KR20200104913A (en) | FMCW radar sensor | |
| KR20120106567A (en) | Radar apparatus supporting short and long range radar operation | |
| JP2011215114A (en) | Radar apparatus and computer program | |
| RU95860U1 (en) | RADAR MODULE | |
| US11960023B2 (en) | Radar device | |
| US11486996B2 (en) | Radar device and antenna device | |
| RU2429501C1 (en) | Detection and direction finding method of air objects |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| 121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 11836706 Country of ref document: EP Kind code of ref document: A1 |
|
| NENP | Non-entry into the national phase |
Ref country code: DE |
|
| 122 | Ep: pct application non-entry in european phase |
Ref document number: 11836706 Country of ref document: EP Kind code of ref document: A1 |