New apparatus comprise a comprises an optical fiber based rf signal train generator for storing transient rf pulses and regenerating the identical replicas for analysis. The apparatus further comprise comprises an rf receivers receiver to process one stored pulse with a reference to other another stored pulse. The present invention drastically increases our abilities to investigate acoustical, electromagnetic, and optical transient phenomena.
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0. 21. An interferoceiver comprising:
an input system which receives one or more signals and outputs rf signals; an rf signal train generator which receives the rf signals from the input system and outputs multiple paired replicas of the rf signals.
0. 37. A method for investigating one or more signals comprising steps of:
receiving the one or more signals and outputting rf signals; receiving the rf signals by an rf signal train generator; and outputting multiple paired replicas of the rf signals.
0. 46. A method for investigating one or more signals comprising steps of:
receiving the one or more signals; outputting one or more rf signals and regenerating a train of replicas of the rf signals; and sampling the regenerated replicas in the train with different delays.
9. A method for operating an interferoceiver comprising steps of:
(a) storing one or more rf signals from a source in an rf signal train generator; (b) regenerating replicas of the one or more stored rf signals from the rf signal train generator; and (c) pairing the regenerated replicas.
0. 42. An apparatus for investigating one or more signals comprising:
an input system which receives the one or more signals and outputs rf signals; an rf signal train generator which receives the rf signals from the input system and regenerates a train of replicas; and a receiver which samples the regenerated replicas in the train with different delays.
17. An apparatus for investigating transient phenomena comprising:
an input system for receiving an rf pulse from a source and for applying the rf pulse to an rf signal train generator; wherein the rf signal train generator comprises:
means, responsive to the input, for storing the rf pulse; means for regenerating a train of replicas from the stored rf pulse; and means for sampling regenerated replicas in the train with different delays.
1. An interferoceiver comprising:
an input system for receiving one or more rf signals from a source and for applying the one or more rf signals to an rf signal train generator; wherein the rf signal train generator comprises:
means, responsive to the input, for storing the one or more rf signals; means for regenerating replicas of the one or more stored rf signals; means for pairing the regenerated replicas; and means for outputting the paired replicas.
2. The interferoceiver of
0. 3. The interferoceiver of
0. 4. The interferoceiver of
0. 5. The apparatus of
0. 6. The interferoceiver of
0. 7. The interferoceiver of
0. 8. The interferoceiver of
10. The method of
(d) processing the replicas in a reference to their pairs.
0. 11. The method of
(e) generating an acoustical signal from the source; (f) splitting the acoustical signal into parts; (g) sending one of part to the rf signal train generator and send other parts through a system under test to the rf signal train generator; and (h) converting acoustical signals to rf signals.
0. 12. The method of
(e) generating an acoustical signal from the source; (f) sending the acoustical signal to a system under test; (g) splitting the acoustical signal by the system under test and sending the split acoustical signals to the rf signal train generator; and (h) convening acoustical signals to rf signals.
0. 13. The method of
(e) generating an rf signal from the source; (f) splitting the rf signal into pans; and (g) sending one of part to the rf signal train generator and send other parts through a system under test to the rf signal train generator.
0. 14. The method of
(e) generating an rf signal from the source; (f) sending the rf signal to a system under test; and (g) splitting the rf signal by the system under test and sending the split rf signals to the rf signal train generator.
0. 15. The method of
(e) generating an optical signal from the source; (f) splitting the optical signal into parts; (g) sending one of parts to the rf signal train generator and send other parts through a system under test to the rf signal train generator; and (h) converting optical signals to rf signals.
0. 16. The method of
(e) generating an optical signal from the source; (f) sending the optical signal to a system under test; (g) splitting the optical signal by the system under test and sending the split acoustical signals to the rf signal train generator; and (h) converting optical signals to rf signals.
0. 18. The apparatus of
0. 19. The apparatus of
wherein the apparatus further comprises means for processing the replicas of the first pulse with a reference to the replicas of the second pulse.
0. 20. The apparatus of
0. 22. The interferoceiver of
0. 23. The interferoceiver of
0. 24. The interferoceiver of
wherein the source emits one or more signals; wherein a splitter splits the one or more signals into a first group of signals and a second group of signals; wherein the second group of signals transits to, and interacts with, a system; and wherein the input system is adapted to receive the first group of signals and the interacted second group of signals.
0. 25. The interferoceiver of
wherein the source emits one or more signals which interact with a system; and wherein the input system is adapted to receive the interacted one or more signals.
0. 26. The interferoceiver of
wherein the input system comprises a splitter which splits the one or more signals.
0. 27. The interferoceiver of
wherein the rf signal train generator comprises a pairing apparatus which pairs the generated replicas.
0. 28. The interferoceiver of
wherein the rf signal train generator comprises an optical store which stores the rf signals as optical rf signals.
0. 29. The interferoceiver of
wherein the rf signal train generator comprises an extractor which generates replicas of the optical rf signals stored in the optical store.
0. 30. The interferoceiver of
wherein the optical store and the extractor are configured so that the replicas generated by the extractor are paired.
0. 31. The interferoceiver of
wherein the optical store comprises one or more optical rf delay loops, or comprises one delay lines.
0. 32. The interferoceiver of
wherein the rf receiver comprises a digitizer which analyzes the paired replicas of the rf signals by using one of the paired replicas as triggering pulses to sample another one of the paired replicas.
0. 33. The interferoceiver of
wherein the digitizer further comprises a delay apparatus which systematically delays the triggering pulses.
0. 34. The interferoceiver of
wherein the rf receiver comprises a coherent receiver which analyzes the paired replicas of the rf signals by using one of the paired replicas as a reference to produce relative amplitudes and phases or relative frequency differences between the rf signals.
0. 35. The interferoceiver of
wherein the input system is adapted to receive at least one of optical, infrared, acoustical, electromagnetic, mechanical, or nuclear signals.
0. 36. The apparatus of
wherein the input system is adapted to output optical rf signals, and the rf signal train generator is adapted to receive optical rf signals.
0. 38. The method of
pairwise analyzing the paired replicas.
0. 39. The method of
emitting the one or more signals from a source.
0. 40. The method of
splitting the one or more signals into a first group of signals and a second group of signals; interacting the second group with a system; and wherein the step of receiving comprises steps of receiving the first group of signals and the interacted second group of signals.
0. 41. The method of
interacting the one or more signals with a system; and wherein the step of receiving comprises a step of receiving the interacted one or more signals.
0. 43. The apparatus of
wherein the receiver further comprises a correlator.
0. 44. The apparatus of
wherein the receiver is adapted to output a data stream, and to send the data stream to a medium.
0. 45. The apparatus of
wherein the input system is adapted to output optical rf signals, and the rf signal train generator is adapted to receive optical rf signals.
0. 47. The method of
producing a data stream; and sending the data system to a medium.
0. 48. The method of
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This application is a continuation-in-part of application Ser. No. 18,388 filed Feb. 17, 1993
As those of ordinary skill in the art will readily appreciate, embodiments of the present invention may not comprise an optical fiber RF storage subsystem as in comparison with optical fiber based radars for temporal alignment of two input pulses. The path length difference of two paths from a source to the RF signal train generator usually is small and can be simply adjusted through conventional RF means, which are known to those of ordinary skill in the art. However, if the need arises, one may introduce an optical fiber RF storage subsystem as well. Embodiment of the optical fiber RF storage subsystem is described in the parent patent application of optical fiber based radars. Furthermore, one may double one of the optical fiber delay loop in the RF signal train generator as the optical fiber RF storage subsystem.
RF receiver (RFR) 30 uses direct digitizing and coherent receiving methods to process pulse trains 250 and 260 from RF signal train generator 200. These methods are well known to those of ordinary skill in the art. The direct digitizing method uses one train as triggering pulses to instruct the digitizer to sample the respective pulses of the second train. The triggering is systematically delayed in sampling the sequential pulses of the second train. The direct digitizing method yields the intrinsic structure of the initial pulse, which generates the second pulse train. The coherent receiving method, based on the intra pulse coherence, uses the pulses of one train as reference to process variational differences of their respective pulses of the second train. The mechanism to achieve intra pulse coherence was proposed in the parent patent application of optical fiber based bistatic radar. The coherent receiving method yields the relative amplitudes and phases, or the relative frequency differences between RF pulses 210 and 220. Furthermore, RFR 30 will correlate pulse trains 250 and 260 to achieve a precise determination of their variational differences. The manner in which RFR 30 processes RF pulse trains is well known to those of ordinary skill in the art. As those of ordinary skill in the art will readily appreciate, RF signal train generator 200 of the present invention virtually mimics multiple pulses for RFR 30 to decipher the information contained in RF pulses 210 and 220.
As those of ordinary skill in the art will readily appreciate, embodiments other than the specific architecture shown in
During an operation, source 310 generates acoustical, electromagnetic, or optical signals for transit along path 311. Splitter 320 uses the signals from path 311 as input and outputs two split signals. Furthermore, splitter 320 applies two split signals to two paths 321 and 322 for transit to converters 323 and 324. Converters 323 and 324 then use the signals from paths 321 and 322 as inputs and convert them respectively to optical RF signals. Converters 323 and 324 may simply pass through these signals, if conversions are not needed. Converters 323 and 324 further apply optical RF signals respectively from paths 321 and 322 to optical fiber paths 325 and 326 for transit to RF signal train generator 200. RF signal train generator 200 uses optical RF signals as input and outputs two pulse trains with respective to optical RF signals from paths 325 and 326. RF signal train generator 200 further applies two pulse trains respectively to optical fiber paths 327 and 328 for transit to RFR 30. RFR 30 uses pulse trains from optical fiber paths 327 and 328 as inputs to process these two pulse trains.
RFR 30 may further comprise phase shifters and delay lines for processing transient signals from source 310. Furthermore, as is well known to those of ordinary skill in the art, RFR 30 will yield the spectrum of the signals, transient and intrinsic characteristics of source 310, and turbulence characteristics of the media surrounding source 310.
As those of ordinary skill in the art will readily appreciate, embodiment of interferoceiver 300 will leads to investigation of many transient and nonrepeatable signals in acoustics, electromagnetism, and optics. Those signals in acoustics are the blasts, explosions, thunders, etc . . . . Those signals in electromagnetism are electromagnetic pulses from lightning, violent electromagnetic discharge, electromagnetic pulse of opportunity, electromagnetic pulses emitted by nuclear blasts and celestial objects, etc . . . . Those signals in optics are the lights emitted by atoms and molecules in a turbulent media of burning, discharge, plasma, lightning, etc . . . . Furthermore, all the above mentioned signals are well know to those of ordinary skill in the art.
During an operation, source 410 generates acoustical, electromagnetic, or optical signals for transit along path 411. Splitter 420 uses the signals from path 411 as input and outputs two split signals. Furthermore, splitter 420 applies two split signals to two paths 421 and 422 for transit to converters 423 and 325. Signal of path 422 transits through system under test 430. Intrinsic charateristics of system under test 430 is random, chaotic, turbulent, or transient. As those of ordinary skill in the art will readily appreciate that signal of path 422 will interact with system under test and be tainted with the intrinsic characteristics of system under test 430 after the transit. Then converters 423 and 424 use the signals from paths 421 and 422 as inputs and convert them respectively to optical RF signals. Converters 423 and 424 may simply pass through these signals, if conversions are not needed. Converters 423 and 424 further apply optical RF signals respectively from paths 421 and 422 to optical fiber paths 425 and 426 for transit to RF signal train generator 200. RF signal train generator 200 uses optical RF signals as input and outputs two pulse trains with respect to optical RF signals from paths 425 and 426. RF signal train generator 200 further applies two pulse trains respectively to optical fiber paths 427 and 428 for transit to RFR 30. RFR 30 uses pulse trains from optical fiber paths 427 and 428 as inputs to process signal train from path 428 by using signal train from path 427 as a reference. As is well known to those of ordinary skill in the art, the reference signals from splitter 420 through path 421, converter 423, path 425, RF signal train generator 200, path 427 to RFR 30 are protected from external contamination and interference.
As those of ordinary skill in the art will readily appreciate, embodiment of interferoceiver 400 is well suited for investigating random, chaotic, turbulent, or transient features of emitting source 410 and system under test 430. The observed intrinsic traits and variational differences contain information on both emitting source 410 and system under test 430. With a known and pulsed source 410, the processing of signal train from fiber optical path 428 by RFR 30 yields the intrinsic characteristics of the random, chaotic, turbulent, or transient traits within system under test 430. As those of ordinary skill in the art will further appreciate, a coincident circuit may be needed to coordinate the source pulse with a transient event from system under test 430. Furthermore, RFR 30 will separate stable traits of system under test 430 from its random, chaotic, turbulent, or transient features. The method of separation is well known to those of ordinary skill in the art.
As those of ordinary skill in the art will readily appreciate, embodiment of interferoceiver 400 with a pulsed ultrasonic source 410 will lead to diffraction tomography for unstable systems. An unstable motion leads to Doppler shift disturbances in diffraction fields and tomographic image blurring. Embodiment of interferoceiver 400 will further lead to ultrasonic imaging of unstable objects and of fetus. As it is well known to those of ordinary skill in the art, RFR 30 through Fourier transformation and moving center correction will remove Doppler shift disturbances and sharp ultrasonic images of these systems.
As those of ordinary skill in the art will appreciate, embodiment of interferoceiver 400 with a pulsed electromagnetic source 410 will use solid means of coaxial cables and wave guides to transit its electromagnetic signals. For example, a single pulse from the pulsed electromagnetic source 410 will lead to the determination of location and speed for a fly in a transverse electromagnetic cell. As is well known to those of ordinary skill in the art, a conventional methods will only able to determine the location of a fly at rest from a single electromagnetic pulse.
As those of ordinary skill in the art will readily appreciate, embodiment of interferoceiver 400 may use a an electromagnetic pulse from lightning as a source and cloud layers as system under test 430. RFR then will provide a detailed information concerning the structures of these layers.
As those of ordinary skill in the art will appreciate, embodiment of interferoceiver 400 with a continuous wave (CW) laser source 410 and a an electromagnetic pulse sensor as system under test 430 will lead to the capture of a single electromagnetic event. Furthermore, RFR 30 will provide a detailed information concerning transient traits and electromagnetic spectrum of the event.
As those of ordinary skill in the art will further appreciate, embodiment of interferoceiver 400 with a pulsed laser source 410 will lead to light scatterings by atoms, molecules, microorganisms, medium fluctuations, plasmas, and particles suspended in chaotic media, and many others. As is well known to those of ordinary skill in the art, the scattered lights are affected by the initial positions and velocities of micro objects and statistical properties of media. As is well known to those of ordinary skill in the art, motion of micro objects and turbulence of media will lead to Doppler frequency shifts in scattered lights. As those of ordinary skill in the art will appreciate, RFR 30 through Fourier transformation will reveal the Doppler spectra associated with the motion and turbulence, and their statistical distributions. As those of ordinary skill in the art will appreciate, embodiment of interferoceiver 400 will provide a much better tool than conventional methods in revealing intrinsic characteristics of atoms, molecules, microorganisms, medium fluctuations, plasmas, and particles suspended in chaotic media, and many others.
As those of ordinary skill in the art readily appreciate, embodiment of interferoceiver 400 with a pulsed laser source 410 will lead to lidars and laser velocimeters. Conventional lidars, which are based on pulsed lasers, only measure the ranges of reflecting objects. Conventional laser velocimeters, which are based on CW lasers, only measure the Doppler shifts from seeded particles. Lidars and laser velocimeters of the present invention, with a help of optical fiber RF storage subsystems, will have both the ranging and Doppler capabilities. As those of ordinary skill in the art will further appreciate, the distinction between lidars and laser velocimeters disappears in the teaching of the present invention. With a subnanosecond pulse source, we will be able to locate constituents in a large reflecting assembly and measure their individual Doppler shift frequencies. As those of ordinary skill in the art will readily appreciate, the teachings from the parent patent applications of optical fiber based bistatic radar and optical RF stereo will lead to the embodiments for fabricating optical fiber based bistatic lidar and optical light stereo.
As those of ordinary skill in the art will further appreciate, the incident and scattered laser pulses may be unsuitable for direct feeding to optical fibers. A second laser can be deployed to down convert the incident and scattered laser pulses to RF signals, then with the help of optical fiber RF converters to up convert the RF signals to optical RF signals for transit through optical fibers to RF signal train generator. The processes of down and up conversions of laser pulses are well known to those of ordinary skill in the art.
During an operation, source 510 generates acoustical, electromagnetic, or optical signals for transit along path 511. System under test 530 uses the signals from path 511 as input, interacts with the signals, and outputs two split signals. Furthermore, system under test 530 applies two split signals to two paths 521 and 522 for transit to converters 523 and 524. Then converters 523 and 524 use the signals from paths 521 and 522 as inputs and convert them respectively to optical RF signals. Converters 523 and 524 may simply pass through these signals, if conversions are not needed. Converters 523 and 524 further apply optical RF signals respectively from paths 521 and 522 to optical fiber paths 525 and 526 for transit to RF signal train generator 200. RF signal train generator 200 uses optical RF signals as input and outputs two pulse trains with respective to optical RF signals from paths 525 and 526. RF signal train generator 200 further applies two pulse trains respectively to optical fiber paths 527 and 528 for transit to RFR 30. RFR 30 uses pulse trains from optical fiber paths 527 and 528 as inputs to process signal train from one path by using signal train from the other path as reference.
As those of ordinary skill in the art will appreciate, for example, embodiment of interferoceiver 500 with a pulsed laser source 510 will lead to the correlation of scattered lights in a light scattering process. The correlation yields the Doppler shift difference between two scattered lights. The mechanism of Doppler shift difference determination was proposed in the parent patent application of optical RF stereo. RFR 30 through Fourier transformation will reveal the spectra of the Doppler shift difference associated with the motion of micro objects and turbulence of media, and their statistical distributions.
Embodiments of the present invention will provide advanced means to upgrade conventional digitizing receivers and interferometers than those furnished by the prior art. As those of ordinary skill in the art will further appreciate, embodiments of the present invention provide added upgrades to the existing digitizing receivers and interferometers without modification, which in turn will be more cost effective and will not interrupt their normal operation.
Embodiments of the present invention will enhance the functional diversities of conventional digitizing receivers and interferometers. In addition, the use of RF signal train generators makes it possible for digitizing receivers and interferometers to completely decipher a single transient event without instability blurring. Furthermore, embodiments of the present invention enable digitizing receivers and interferometers to determine intrinsic traits and Doppler spectrum of a single RF pulse.
Embodiments of the present invention will be able to reveal many hidden mechanisms governing many statistical phenomena. For instance, Doppler spectra of a chaotic medium and a turbulent flow could not be directly observed. Statistical properties of the Doppler spectra now can be systematically investigated. As those of ordinary skill in the art will appreciate, embodiments of the present invention will lead to better understandings of the chaotic media and turbulent flows.
As those of ordinary skill in the art will readily appreciate, averaging with respect to multiple pulses will smear many critical information concerning the system under test. Embodiments of the present invention use a single pulse rather than multiple repetitive pulses. The embodiment will make digitizing receivers and interferometers more versatile and sophisticated in exposing many critical information. As those of ordinary skill in the art will still further appreciate, embodiments of the present invention will lead to better understandings of random, chaotic, turbulent, or transient phenomena.
Embodiments of the present invention will be able to sharpen ultrasonic images. Furthermore, embodiments of the present invention will be able to separate the images of stationary constituents from that of moving constituents. As those of ordinary skill in the art will equally appreciate, optical fiber based radars will also sharpen synthetic aperture radar (SAR) images, and separate SAR images of stationary constituents from that of moving constituents.
Embodiments of the present invention will be able to reveal intrinsic traits of an active system. Intrinsic traits of an active system is are inherited, like imperfection in a diamond. As those of ordinary skill in the art will equally appreciate, optical fiber based radars and passive RF systems will provide excellent means in revealing the unintended modulation on pulse by active and passive objects.
Embodiments of the present invention will be advantageous to disclose internal constituents of a system and to reveal their characteristics. As those of ordinary skill in the art will equally appreciate, optical fiber based radars and passive RF system systems possess excellent means in suppression of clutter returns and of multiple path interferences.
Embodiments of the present invention, as shown in
Embodiments of the present invention will be advantageous in destructive testings, for example, automobile collision tests. Transient signals from various sensors will be thoroughly analyzed by interferoceivers. Embodiments of the present invention will provide better understandings as well as reducing the costs in destructive tests.
Quantum mechanics is a mechanics of coherent. Many interesting coherent phenomena implicated by Einstein, Podolsky, and Rosen paradox are still waiting for us to discover. Embodiments of the present invention will provide us new tools for us to discover these interesting phenomena.
Those skilled in the art readily recognize that embodiments of the present invention may be made without departing from its teachings. For example, the interferoceivers may have many designs as well as different variations. The source of an interferoceiver may play the role of a splitter as well. Two signals at different angle perspectives from a source are sent directly to the RF signal train generator. An interferoceiver may compare two sequential events from a source with the help from an optical fiber RF storage subsystem to temporally align these two events. Such a comparison leads to inter pulse coherence. The mechanism to achieve inter pulse coherence was proposed in the parent patent application of optical fiber based radars. Thus the scope of the invention should be determined by appended claims and their legal equivalent, rather by the examples presented here.
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