WO2023108807A1 - 光学毫米波/太赫兹传递系统和传递方法 - Google Patents

光学毫米波/太赫兹传递系统和传递方法 Download PDF

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Publication number
WO2023108807A1
WO2023108807A1 PCT/CN2021/141501 CN2021141501W WO2023108807A1 WO 2023108807 A1 WO2023108807 A1 WO 2023108807A1 CN 2021141501 W CN2021141501 W CN 2021141501W WO 2023108807 A1 WO2023108807 A1 WO 2023108807A1
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optical
signal
optical coupler
filter
acousto
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PCT/CN2021/141501
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English (en)
French (fr)
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胡亮
李奇
吴龟灵
刘娇
陈建平
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上海交通大学
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Priority claimed from CN202111522543.6A external-priority patent/CN114172584B/zh
Priority claimed from CN202111522505.0A external-priority patent/CN114142940B/zh
Application filed by 上海交通大学 filed Critical 上海交通大学
Priority to US17/941,012 priority Critical patent/US20230188216A1/en
Publication of WO2023108807A1 publication Critical patent/WO2023108807A1/zh

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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
    • H04B10/40—Transceivers
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
    • H04B10/50—Transmitters
    • H04B10/516—Details of coding or modulation
    • H04B10/548—Phase or frequency modulation
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
    • H04B10/60—Receivers
    • H04B10/61—Coherent receivers
    • H04B10/64—Heterodyne, i.e. coherent receivers where, after the opto-electronic conversion, an electrical signal at an intermediate frequency [fIF] is obtained

Definitions

  • the invention relates to optical fiber time and frequency transmission, in particular to an optical millimeter wave/terahertz transmission system and transmission method.
  • the purpose of the present invention is to provide a distributed optical millimeter wave/terahertz transmission system and transmission method for the deficiencies of the prior art and work.
  • the present invention extracts the forward and backward transmitted optical signals through the optical coupler, and after optical signal filtering, photoelectric conversion, microwave filtering, frequency division and optical frequency shift processing, the phase can be obtained at any position of the transmission link Stable mmWave/THz signal.
  • the scheme also has the characteristics of high reliability, simple structure and low implementation cost.
  • the present invention provides a high-precision optical millimeter wave/terahertz transmission system, which is characterized in that it includes a local terminal, a transmission link and a user terminal:
  • the local end includes an optical isolator unit, a first optical coupler, a first Faraday rotating mirror, a second optical coupler, a first optical filter, a second optical filter, a first acousto-optic frequency shifter, a second A microwave source, a second acousto-optic frequency shifter, a third optical coupler, a third optical filter, a fourth optical filter, a first photoelectric conversion unit, a second photoelectric conversion unit, a first electrical filter, a second an electrical filter, a first mixer, a servo control unit, a voltage controlled oscillator and a fourth optocoupler;
  • the user terminal includes a third acousto-optic frequency shifter, a second microwave source, a fifth optical coupler, a second Faraday rotating mirror, a sixth optical coupler, a third microwave source, a first optical phase-locked unit, a microwave a power divider, a second optical phase-locked unit, a seventh optical coupler, a third photoelectric conversion unit and a third electrical filter;
  • the light-carrying millimeter-wave signal E0 to be transmitted is divided into two paths through the optical isolator and the first optical coupler in sequence, one of which is reflected by the first Faraday rotating mirror and returns to the first optical coupler as a local reference
  • the light is input to the third optical coupler; the other path is divided into two paths again through the second optical coupler, which are respectively passed through the first optical filter and the first acousto-optic frequency shifter, and the second optical filter
  • the output of the second acousto-optic frequency shifter, the two-way signals are combined by the fourth optical coupler, and then transmitted to the user end through the transmission link;
  • the E3 signal After passing through the third acousto-optic frequency shifter and the fifth optical coupler at the user end, the E3 signal is divided into two parts, one part of which is reflected by the second Faraday rotating mirror , transmitted to the local end through the transmission link, after being split by the fourth optical coupler again, returning along the original path, after combining the beams by the second optical coupler, and passing through the 3 beams of the first optical coupler Port input, 4 port output, input the third optical coupler together with the local reference light, divided into two paths again by the third optical coupler, one path passes through the third optical filter, the first photoelectric The conversion unit and the first electric filter enter the first mixer, and the other path passes through the fourth optical filter, the second photoelectric conversion unit and the second electric filter in turn.
  • the two-way signal is mixed by the first mixer to remove the sideband, and output a DC error signal to enter the servo control unit;
  • the other part of the E3 signal is divided into two paths after passing through the sixth optical coupler, one path passes through the first optical phase-locked unit, the other path passes through the second optical phase-locked unit, and the other path passes through the optical phase-locked unit.
  • the last two paths of optical signals respectively enter the beams of the seventh optical coupler and are filtered by the third photoelectric conversion unit and the third electrical filter to obtain a stable millimeter wave signal.
  • the transmission link is an optical fiber link or a free space link
  • the free space link is composed of a free space optical transmitting module, a receiving module and a free space link.
  • the optically-carried millimeter-wave signal E 0 is divided into two parts after passing through the optical isolator and the first optical coupler: a part of the optical-carried millimeter-wave signal E 0 is reflected by the first Faraday rotating mirror After passing through the first optical coupler, it is input to the third optical coupler as the local reference light, and another part of the light-carrying millimeter-wave signal E0 is divided into two paths by the second optical coupler,
  • the output signal after one path passes through the first optical filter and the first acousto-optic frequency shifter is denoted as E 1
  • the other path passes through the second optical filter and the second acousto-optic frequency shifter.
  • the signal output after the frequency converter is recorded
  • ⁇ RF1 Respectively, the frequency and initial phase of the radio frequency of the first acousto-optic frequency shifter, ⁇ vco , Respectively, the frequency and initial phase of the radio frequency of the second acousto-optic frequency shifter;
  • ⁇ RF2 are the frequency and initial phase of the RF operation of the third acousto-optic frequency shifter; it should be noted that the microwave source used in the system has no phase synchronization relationship with the optical-carried millimeter-wave signal to be transmitted.
  • the E3 signal passes through the fifth optical coupler and is divided into two parts: one part is reflected into the transmission link after passing through the second Faraday rotating mirror, and then transmitted to the fourth After the optical coupler, after successively going through the reciprocal path of the E1 and E2 signals, it passes through the ports 3 and 4 of the first optical coupler and is transmitted to the third optical coupler 1 port, its expression is:
  • E 4 signal and the local reference optical signal E 0 are divided into two paths after passing through the third optical coupler: one path in turn After passing through the third optical filter, the first photoelectric conversion unit and the first electrical filter, the output signal is denoted as E 5 , and the other path passes through the fourth optical filter, the After the second photoelectric conversion unit and the second electric filter, the output signal is denoted as E 6 , and the expressions of E 5 and E 6 are respectively:
  • the output DC error signal Ve enters the servo control unit, and its expression is:
  • E 3 signal described in the other part is divided into two paths after passing through the sixth optical coupler: the signal output after one path passes through the first optical phase-locked unit is recorded as E 7 , and the other path passes through the The signal outputted after the second optical phase-locked unit is denoted as E 8 , and the expressions of the E 7 and E 8 signals are respectively:
  • the present invention also provides a distributed optical millimeter wave/terahertz transmission system, which is characterized in that it includes a local terminal, a transmission link, a user terminal and an access terminal:
  • the local end includes an optical isolator unit, a first optical coupler, a first Faraday rotating mirror, a second optical coupler, a first optical filter, a second optical filter, a first acousto-optic frequency shifter, a second A microwave source (17), a second acousto-optic frequency shifter (18), a third optical coupler, a third optical filter, a fourth optical filter (21), a first photoelectric conversion unit (22), a second Photoelectric conversion unit (23), first electric filter (24), second electric filter (25), first mixer (26), servo control unit (27), voltage controlled oscillator (28) and the first Four optical couplers (29);
  • the user end (3) includes a third acousto-optic frequency shifter (30), a second microwave source (31), a fifth optical coupler (32), a second Faraday rotating mirror (33), a sixth optical coupling device (34), the third microwave source (35), the first optical phase-locked unit (36), microwave power splitter (37), the second optical phase-locked unit (38), the seventh optical coupler (39), A third photoelectric conversion unit (40) and a third electric filter (41);
  • the light-carrying millimeter-wave signal E0 to be transmitted is divided into two paths through the optical isolator (10) and the first optical coupler (11) successively, and one of them is reflected by the first Faraday rotating mirror (12), and returns to the
  • the first optical coupler (11) of the local reference optical signal E 0 is input to the described third optical coupler (19); the other path is divided into two paths again through the second optical coupling (13), respectively
  • the output of the first optical filter (14) and the first acousto-optic frequency shifter (16), and the second optical filter (15) and the second acousto-optic frequency shifter (18) the two-way signal E 1 , E 2.
  • the fourth optical coupler (29) After being combined by the fourth optical coupler (29), it is transmitted to the user end (3) through the transmission link (2);
  • the signal E3 is divided into two parts, one part of which is passed through the After being reflected by the second Faraday rotating mirror (33), it is transmitted to the local end (1) through the transmission link (2), and after being split by the fourth optical coupler (29), it returns along the original path.
  • the third optical coupler ( 19) After the beam combination of the second optical coupler (13), through the 3-port input of the first optical coupler (11), after the 4-port output, together with the local reference light, input the third optical coupler ( 19), divided into two paths again through the third optical coupler (19), one path passes through the third optical filter (20), the first photoelectric conversion unit (22) and the first electric filter in turn (24) after entering the first mixer (26), the other way passes through the fourth optical filter (21), the second photoelectric conversion unit (23) and the second electric filter in sequence Enter the first described mixer (26) after (25), after the two-way signal mixes and takes off sideband through this first mixer (26), the output DC error signal enters described servo control unit (27) ), driving the voltage-controlled oscillator (28) to realize phase noise compensation;
  • the other part is divided into two paths after passing through the sixth optical coupler (34) through the signal E3 , and enters the first optical phase-locking unit (36) and the second optical phase-locking unit (38) respectively.
  • the RF signal output by the third microwave source (35) is divided into two paths through the microwave power divider (37) and enters the first optical phase-locking unit (36) and the second optical phase-locking unit (38) respectively.
  • the access terminal includes an eighth optical coupler, a ninth optical coupler, a tenth optical coupler, a fifth optical filter, a fourth photoelectric conversion unit, a fourth electrical filter, a first frequency divider unit, The sixth optical filter, the fifth photoelectric conversion unit, the fifth electrical filter, the second frequency divider unit, the seventh optical filter, the fourth acousto-optic frequency shifter, the eighth optical filter, the fifth acousto-optic shifter Frequency converter, eleventh optical coupler, sixth photoelectric conversion unit and sixth electric filter;
  • the eighth optical coupler is located at any node of the transmission link, and is used to obtain the forward-transmitted optical signal and the backward-transmitted optical signal; the forward-transmitted optical signal passes through the first
  • the nine optical couplers are divided into three paths, the first path is divided into two parts after being combined with the optical signal transmitted backward by the tenth optical coupler, and one part passes through the fifth optical filter,
  • the fourth photoelectric conversion unit, the fourth electrical filter and the first frequency divider unit are loaded on the fourth acousto-optic frequency shifting; the other part passes through the sixth optical filter, the fifth photoelectric conversion unit,
  • the fifth electrical filter and the second frequency divider unit are loaded on the fifth acousto-optic frequency shifter;
  • the second path passes through the seventh optical filter and the fourth acousto-optic frequency shifter in sequence and then enters the
  • the eleventh optical coupler mentioned above, the third path passes through the eighth optical filter and the fifth acousto-optic frequency shifter in sequence, and then
  • the transmission link is an optical fiber link or a free space link
  • the free space link is composed of a free space optical transmitting module, a receiving module and a free space link.
  • the transmission method using the above-mentioned distributed optical millimeter wave/terahertz transmission system is characterized in that the specific steps of the method are as follows:
  • the optically-carried millimeter-wave signal E0 is divided into two paths after passing through the optical isolator and the first optical coupler: one path is reflected by the first Faraday rotating mirror, and then passed through the first
  • the optical coupler is then input to the third optical coupler as a local reference light, and the other path is divided into two parts after passing through the second optical coupling, and a part of the E0 optical signal passes through the first
  • the output signal after an optical filter and the first acousto-optic frequency shifter is denoted as E 1
  • another part of the E 0 optical signal passes through the second optical filter and the second acousto-optic frequency shifter.
  • the signal output after the frequency shifter is recorded as E2 , and the expression
  • ⁇ RF1 Respectively, the frequency and initial phase of the radio frequency of the first acousto-optic frequency shifter, ⁇ vco , Respectively, the frequency and initial phase of the radio frequency of the second acousto-optic frequency shifter;
  • the E3 signal is divided into two parts through the fifth optical coupler: one part is reflected by the second Faraday rotating mirror and enters the transmission link, and is transmitted to the first transmission link at the local end.
  • the four optical couplers after successively going through the reciprocal path of the E1 and E2 signals, they pass through the ports 3 and 4 of the first optical coupler and are transmitted to the third optical coupler 1 port of , its expression is:
  • the output DC error signal Ve enters the servo control unit, and its expression is:
  • the optical signal transmitted forward and backward is obtained through the eighth optical coupler, the expression of which is:
  • the E10 signal is divided into three paths through the ninth optical coupler, and one path is divided into two parts after being combined with the E11 signal by the tenth optical coupler, and one part passes through the After the fifth optical filter, the fourth photoelectric conversion unit, the fourth electrical filter, and the first frequency divider unit, the output signal is denoted as E 12 , and the other part passes through the After the sixth optical filter, the fifth photoelectric conversion unit, the fifth electrical filter, and the second frequency divider unit, the output signal is denoted as E 13 , and the E 12 and The E13 signal is respectively loaded on the fourth acousto-optic frequency shifter and the fifth acousto-optic frequency shifter, and its expression is:
  • phase noise introduced by the link has the following relationship
  • the E14 signal can be further rewritten as:
  • the E14 passes through the sixth photoelectric conversion unit and the sixth electric filter, and its output signal expression is:
  • Both the user end and any access end can obtain stable millimeter wave/terahertz signals.
  • the phase compensation of the transmission link can be realized without the need of synchronizing with the millimeter-wave signal by a local reference source, and at the same time, the backscattering noise in the system is effectively suppressed. In addition, it has the characteristics of unlimited compensation range and high reliability.
  • the forward and backward transmission optical signals are extracted through the optical coupler, and after optical signal filtering, photoelectric conversion, microwave filtering, frequency division and optical frequency shift processing, the transmission link is realized.
  • the transmission link is realized.
  • the scheme also has the characteristics of high reliability, simple structure and low implementation cost.
  • Fig. 1 is a schematic structural diagram of an embodiment of the high-precision optical millimeter wave/terahertz transmission system of the present invention.
  • Fig. 2 is a schematic structural diagram of an embodiment of the distributed optical millimeter wave/terahertz transmission system of the present invention.
  • FIG. 1 is a schematic structural diagram of an embodiment of the high-precision optical millimeter-wave transmission system of the present invention. It can be seen from the figure that the high-precision optical millimeter-wave transmission system of the present invention includes a local terminal 1, a transmission link 2 and a user terminal 3:
  • the local terminal 1 includes an optical isolator unit 10, a first optical coupler 11, a first Faraday rotating mirror 12, a second optical coupler 13, a first optical filter 14, a second optical filter 15, First acousto-optic frequency shifter 16, first microwave source 17, second acousto-optic frequency shifter 18, third optical coupler 19, third optical filter 20, fourth optical filter 21, first photoelectric conversion unit 22.
  • the The user terminal 3 includes a third acousto-optic frequency shifter 30, a second microwave source 31, a fifth optical coupler 32, a second Faraday rotating mirror 33, a sixth optical coupler 34, a third microwave source 35, a first optical Phase locking unit 36, microwave power divider 37, second optical phase locking unit 38, seventh optical coupler 39, third photoelectric conversion unit 40 and third electrical filter 41 ;
  • the transmission link 2 is transmitted to the local terminal 1, and after being split by the fourth optical coupler 29, it returns along the original path, after the beam combining of the second optical coupler 13, and the 3-port input, 4-port output, input the third optical coupler 19 together with the local reference light, and divide into two paths again through the third optical coupler 19, and one path passes through the third optical filter 20 in sequence , the first photoelectric conversion unit 22 and the first electrical filter 24, then enter the first mixer 26, and the other channel passes through the fourth optical filter 21, the second photoelectric conversion unit 23 and the
  • the second electric filter 25 enters the first mixer 26, and the two-way signal is mixed by the first mixer 26 to remove the sideband, and the output DC error signal enters the servo control unit 27; the other part is divided into two paths after the E3 signal passes through the sixth optical coupler 34, one path passes through the first optical phase-locking unit 36, and the other path passes through the second optical phase-locking unit 38.
  • the two-way signals after optical phase-locking respectively enter into the beams of the seventh optical
  • the optically-carried millimeter-wave signal E0 passes through the optical isolator 10 and the first optical coupler 11 and is divided into two parts: a part of the optical-carried millimeter-wave signal E0 passes through the first Faraday rotation
  • the mirror 12 is reflected by the first optical coupler 11 and then input to the third optical coupler 19 as local reference light, and another part of the light-carrying millimeter wave signal E 0 passes through the second optical coupler 13
  • the other path passes through the second optical filter 15 and The signal output after the second acousto-optic frequency shifter 18
  • ⁇ RF1 Respectively the frequency and initial phase of the radio frequency of the first acousto-optic frequency shifter 16, ⁇ vco , Respectively, the frequency and initial phase of the radio frequency of the second acousto-optic frequency shifter 18;
  • ⁇ RF2 In the formula, and represent the phase noise introduced by the transfer link, ⁇ RF2 and They are respectively the frequency and initial phase of the radio frequency operation of the third acousto-optic frequency shifter 30; the frequency shift signal E 3 is divided into two parts through the fifth optical coupler 32: one part passes through the After the second Faraday rotating mirror 33 reflects and enters the transmission link 2, after being transmitted to the fourth optical coupler 29, after experiencing the reciprocal path of the E1 and E2 signals in sequence, Through the 3 and 4 ports of the first optical coupler 11, it is transmitted to the 1 port of the third optical coupler 19, and its expression is:
  • the output DC error signal Ve enters the servo control unit 27, and its expression is:
  • the servo control unit 27 realizes the pre-compensation of the link phase noise by changing the frequency of the voltage-controlled oscillator 28 in real time.
  • the error The signal is 0, Ve ⁇ 0, the expression can be further written as:
  • the signal E 3 described in the other part is divided into two paths after passing through the sixth optical coupler 34: the signal output after one path passes through the first optical phase-locking unit 36 is marked as E 7 , and the other path
  • the signal output after the second optical phase-locking unit 38 is denoted as E 8 , and the expressions of the E 7 and E 8 signals are respectively:
  • the present invention converts the transmission link phase noise to two intermediate frequency signals for processing by means of double heterodyne detection, and inputs the intermediate frequency signal to a single carrier phase compensation module to complete locking, thereby realizing stable millimeter wave signal transmission.
  • the invention can realize the phase compensation of the transmission link without using a local reference source to synchronize with the millimeter wave signal, and meanwhile effectively suppresses the backscattering noise in the system. In addition, it has the characteristics of unlimited compensation range and high reliability.
  • Fig. 2 is a schematic structural diagram of an embodiment of the distributed optical millimeter wave transmission system of the present invention.
  • the local terminal 1 includes an optical isolator unit 10, a first optical coupler 11, a first Faraday rotating mirror 12, a second optical coupler 13, a first optical filter 14, a second optical filter 15, a first Acoustic optical frequency shifter 16, first microwave source 17, second acousto-optic frequency shifter 18, third optical coupler 19, third optical filter 20, fourth optical filter 21, first photoelectric conversion unit 22 , the second photoelectric conversion unit 23, the first electric filter (24), the second electric filter 25, the first mixer 26, the servo control unit 27, the voltage controlled oscillator (28) and the fourth photocoupler 29 ;
  • the user terminal 3 includes a third acousto-optic frequency shifter 30, a second microwave source 31, a fifth optical coupler 32, a second Faraday rotating mirror 33, a sixth optical coupler 34, a third microwave source 35, a An optical phase-locking unit 36, a microwave power splitter 37, a second optical phase-locking unit 38, a seventh optical coupler 39, a third photoelectric conversion unit 40 and a third electrical filter 41;
  • the light-carrying millimeter-wave signal E0 to be transmitted is divided into two paths through the optical isolator 10 and the first optical coupler 11 in sequence, one of which is reflected by the first Faraday rotating mirror 12 and returns to the first optical coupler 11 is input to the third optical coupler 19 as the local reference optical signal E 0 ; the other path is divided into two paths again through the second optical coupling 13, respectively, through the first optical filter 14 and the first acousto-optic
  • the frequency shifter 16, and the output of the second optical filter 15 and the second acousto-optic frequency shifter 18, the two-way signals E 1 , E 2 are combined by the fourth optical coupler 29, and then transmitted through the Link 2 transfers to client 3;
  • the signal E3 is divided into two parts, one part of which is rotated by the second Faraday After being reflected by the mirror 33, it is transmitted to the local terminal 1 through the transmission link 2, and after being split by the fourth optical coupler 29, it returns along the original path, and after combining the beams by the second optical coupler 13, After the 3-port input and 4-port output of the first optical coupler (11), it is input into the described third optical coupler (19) together with the local reference light, and is divided into two again by the third optical coupler (19).
  • One path one path passes through the third optical filter 20, the first photoelectric conversion unit (22) and the first electric filter 24 in sequence and then enters the first mixer 26, and the other path passes through the The fourth optical filter 21, the second photoelectric conversion unit 23 and the second electrical filter 25 enter the first mixer 26, and the two signals are mixed by the first mixer 26 After removing the sideband, the output DC error signal enters the servo control unit 27 to drive the voltage-controlled oscillator 28 to realize phase noise compensation;
  • the other part is divided into two paths after the signal E passes through the sixth optical coupler 34, and enters the first optical phase-locking unit 36 and the second optical phase-locking unit 38 respectively, and the third microwave source 35 outputs
  • the radio frequency signal is divided into two paths by the microwave power divider 37 and enters the first optical phase-locking unit 36 and the second optical phase-locking unit 38 respectively
  • the access terminal 4 includes an eighth optical coupler 42, a ninth optical coupler 43, a tenth optical coupler 44, a fifth optical filter 45, a fourth photoelectric conversion unit 46, a fourth electrical filter 47,
  • the eighth optical coupler 42 is located at any node of the transmission link 2, and is used to obtain the optical signal transmitted forward and the optical signal transmitted backward; the optical signal transmitted forward is passed through the
  • the ninth optical coupler 43 is divided into three paths, the first path is divided into two parts after being combined with the optical signal transmitted backward by the tenth optical coupler 44, and one part passes through the fifth
  • the optical filter 45, the fourth photoelectric conversion unit 46, the fourth electrical filter 47 and the first frequency divider unit 48 are loaded on the fourth acousto-optic frequency shift 51;
  • the filter 49, the fifth photoelectric conversion unit 50, the fifth electric filter 51 and the second frequency divider unit 52 are loaded on the fifth acousto-optic frequency shifter 56;
  • the second path passes through the seventh
  • the optical filter 53 and the fourth acousto-optic frequency shifter 54 enter the eleventh optical coupler 57, and the third path passes through the eighth optical filter 55 and the fifth acousto-optic frequency shifter in sequence.
  • the transmission link 2 is composed of an optical fiber link
  • the local terminal 1 is located at one end of the transmission link 2
  • the access terminal is located at any position of the transmission link
  • the user terminal 4 is located at the other end of the transmission link 2 .
  • the millimeter wave/terahertz transmission method using the above-mentioned distributed optical millimeter wave/terahertz transmission system is characterized in that the specific steps of the method are as follows:
  • the optically-carried millimeter-wave signal E0 is divided into two paths after passing through the optical isolator 10 and the first optical coupler 11: one path is reflected by the first Faraday rotating mirror 12, and then passed through the After the first optical coupler 11 of the local reference light is input to the third optical coupler 19, the other path is divided into two parts after passing through the second optical coupler 13, and a part of the E 0 light
  • the signal output after the signal passes through the first optical filter 14 and the first acousto-optic frequency shifter 16 is denoted as E 1
  • the other part of the E 0 optical signal passes through the second optical filter 15 and the signal outputted by the second acousto-optic frequency shifter 18 is denoted as E 2
  • ⁇ RF1 Respectively the frequency and initial phase of the radio frequency of the first acousto-optic frequency shifter 16, ⁇ vco , Respectively, the frequency and initial phase of the radio frequency of the second acousto-optic frequency shifter 18;
  • the E3 signal is divided into two parts through the fifth optical coupler 32: a part is reflected into the transmission link 2 after passing through the second Faraday rotating mirror 33, and is transmitted to the local end After the fourth optical coupler 29 described above, after going through the reciprocal paths with the E1 and E2 signals in turn, they pass through the ports 3 and 4 of the first optical coupler 11 and are transmitted to the Port 1 of the third optocoupler 19, its expression is:
  • the output DC error signal Ve enters the servo control unit 27, and its expression is:
  • E 7 and E 8 signals are:
  • the optical signal transmitted forward and backward is obtained through the eighth optical coupler 42, the expression of which is:
  • the E10 signal is divided into three paths through the ninth optical coupler 43, and one path is divided into two parts after being combined with the E11 signal by the tenth optical coupler 44.
  • the output signal is denoted as E12
  • the output signal E13 , the E12 and E13 signals are respectively loaded on the fourth acousto-optic frequency shifter 54 and the fifth acousto-optic frequency shifter 56, and its expression is:
  • phase noise introduced by the link has the following relationship
  • the E14 signal can be further rewritten as:
  • the E14 passes through the sixth photoelectric conversion unit 58 and the sixth electric filter 59, and its output signal expression is:
  • Both the user end and any access end can obtain stable millimeter wave/terahertz signals.
  • the present invention extracts the forward and backward optical signals through the optical coupler in the transmission link, and after optical signal filtering, photoelectric conversion, microwave filtering, frequency division and optical frequency shifting processing, any transmission link can be realized. position to obtain a phase-stabilized mmWave/THz signal.
  • the scheme also has the characteristics of high reliability, simple structure and low implementation cost.

Abstract

一种光学毫米波/太赫兹传递系统和传递方法，系统包括本地端(1)、传递链路(2)、接入端(4)和用户端(3)；在传递链路(2)中通过光耦合器提取出前向和后向传递的光信号，经过光信号滤波、光电转换、微波滤波、分频以及光学移频处理，实现传递链路(2)的任意位置获得相位稳定的毫米波/太赫兹信号。具有可靠性高、结构简单、实现成本低的特点。

Description

光学毫米波/太赫兹传递系统和传递方法 技术领域
本发明涉及光纤时间与频率传递，特别是一种光学毫米波/太赫兹传递系统和传递方法。
背景技术
高稳定频率参考信号的长距离传递已被证明在射电天文学、深空网络中均发挥着重要作用。涉及天线间高精度相位同步的应用通常需要同步良好且时延抖动低的高频率参考信号。传统的基于卫星链路的频率传递受到大气湍流等影响已无法满足诸多高精度应用场景的需求，而基于光纤和空间链路的光学频率传递技术被多次证明是当前突破现有技术限制的一种有效解决方案，其中光纤具有低衰减、宽带宽、高可靠性和抗电磁干扰等优点。近些年来，诸多课题组针对光学毫米波传递提出了许多优秀的传递方案。
然而，目前基于光学毫米波频率传递均是针对点到点的应用场景，还未有报道过分布式的传递方案。为了拓展毫米波/太赫兹信号传递的应用范围，例如满足阿塔卡马大型毫米波阵列(ALMA)项目和超长基线干涉测量(VLBI)等应用需求，我们提出了一种分布式光学毫米波/太赫兹传递方案。
发明内容
本发明的目的在于针对现有技术以及工作的不足，提供一种分布式光学毫米波/太赫兹传递系统和传递方法。本发明在传递链路中通过光耦合器提取出前向和后向传递的光信号，经过光信号滤波、光电转换、微波滤波、分频以及光学移频处理，实现传递链路的任意位置获得相位稳定的毫米波/太赫兹信号。此外，该方案还具有可靠性高、结构简单、实现成本低的特点。
本发明的技术解决方案如下：
一方面本发明提供一种高精度光学毫米波/太赫兹传递系统，其特点在于，包括本地端、传递链路和用户端：
所述的本地端包括光隔离器单元、第一光耦合器、第一法拉第旋转镜、第二光耦合器、第一光滤波器、第二光滤波器、第一声光移频器、第一微波源、第二声光移频器、第三光耦合器、第三光滤波器、第四光滤波器、第一光电转换单元、第二光电转换单元、第一电滤波器、第二电滤波器、第一混频器、伺服控制单元、压控振荡器和第四光耦合器；
所述的用户端包括第三声光移频器、第二微波源、第五光耦合器、第二法拉 第旋转镜、第六光耦合器、第三微波源、第一光锁相单元、微波功分器、第二光锁相单元、第七光耦合器、第三光电转换单元和第三电滤波器；
待传光载毫米波信号E 0经依次经光隔离器和第一光耦合器后分为两路，其中一路经第一法拉第旋转镜反射后，返回所述的第一光耦合器作为本地参考光输入到所述的第三光耦合器；另一路经所述的第二光耦合器再次分为二路，分别经第一光滤波器和第一声光移频器，以及第二光滤波器和第二声光移频器输出，二路信号经所述的第四光耦合器合束后，经所述的传递链路传递到达用户端；
在所述的用户端依次经所述的第三声光移频器和所述的第五光耦合器后E 3信号被分为两部分，其中一部分经所述的第二法拉第旋转镜反射后，经所述的传递链路传递到本地端，再次经第四光耦合器分束后，沿原路返回，经所述的第二光耦合器合束后，经第一光耦合器的3端口输入，4端口输出后，与本地参考光一起输入所述的第三光耦合器，经第三光耦合器再次分为二路，一路依次经所述的第三光滤波器、第一光电转换单元和所述的第一电滤波器后进入所述的第一混频器，另一路依次经所述的第四光滤波器、第二光电转换单元和所述的第二电滤波器后进入所述的第一混频器，二路信号经该第一混频器混频取下边带后，输出直流误差信号进入所述的伺服控制单元；
另一部分E 3信号经过所述的第六光耦合器后被分为两路，一路经所述的第一光锁相单元，另一路经所述的第二光锁相单元，经光锁相后的两路光信号分别进入经所述的第七光耦合器合束后，经所述的第三光电转换单元以及所述的第三电滤波器滤波后即可得到稳定的毫米波信号。
所述的传递链路为光纤链路或者自由空间链路，所述的自由空间链路由自由空间光发射模块、接收模块与自由空间链路组成。
利用上述高精度光学毫米波/太赫兹传递系统的毫米波/太赫兹传递方法，具体步骤如下：
1)本地端待传递的光载毫米波信号为
Figure PCTCN2021141501-appb-000001
其中两个角频率和相位的差值分别与毫米波的频率和相位相匹配，即ω 2-ω 1＝ω mmW，
Figure PCTCN2021141501-appb-000002
所述的光载毫米波信号E 0经过所述的光隔离器、所述的第一光耦合器后分为两部分：一部分光载毫米波信号E 0经过所述的第一法拉第旋转镜反射经所述的第一光耦合器后作为本地参考光输入到所述的第三光耦合器上，另一部分光载毫米波信号E 0经所述的第二光耦合器分为两路后，一路经过所述的第一光滤波器和所述的第一声光移频器后输出的信号记为E 1,另一路经过所述的第二光滤波器和所述的第二声光移频器后输出的信号记为E 2,所述的E 1和E 2信号表达式为：
Figure PCTCN2021141501-appb-000003
Figure PCTCN2021141501-appb-000004
式中，ω RF1，
Figure PCTCN2021141501-appb-000005
分别为所述的第一声光移频器射频工作的频率和初始相位，ω vco，
Figure PCTCN2021141501-appb-000006
分别为所述的第二声光移频器射频工作的频率和初始相位；
2)所述的E 1、E 2信号经过所述的第四光耦合器合束后进入所述的传递链路，在所述的用户端经过所述的第三声光移频器后，输出信号E 3的表达式为：
Figure PCTCN2021141501-appb-000007
式中，
Figure PCTCN2021141501-appb-000008
和
Figure PCTCN2021141501-appb-000009
分别表示传递链路引入的相位噪声，ω RF2和
Figure PCTCN2021141501-appb-000010
分别为所述的第三声光移频器射频工作的频率和初始相位；需要注意的是，系统中所用的微波源均与待传递的光载毫米波信号没有相位同步关系。所述的E 3信号经过所述的第五光耦合器，被分为两部分：一部分经过所述的第二法拉第旋转镜后反射进入到所述的传递链路，传递到所述的第四光耦合器后，依次经历了与所述的E 1和E 2信号互逆的路径后，经过所述的第一光耦合器的3,4端口，传递到所述的第三光耦合器的1端口，其表达式为：
Figure PCTCN2021141501-appb-000011
3)这里假设前向传递和后向传递的链路噪声相等，所述的E 4信号与所述的本地参考光信号E 0经过所述的第三光耦合器后分为两路：一路依次经过所述的第三光滤波器、第一光电转换单元和所述的第一电滤波器后，输出的信号记为E 5，另一路依次经过所述的第四光滤波器、所述的第二光电转换单元和所述的第二电滤波器后，输出的信号记为E 6，所述的E 5和E 6的表达式分别为：
Figure PCTCN2021141501-appb-000012
Figure PCTCN2021141501-appb-000013
所述的E 5和E 6信号通过所述的第一混频器混频取下边带后，输出的直流误差信号Ve进入所述的伺服控制单元，其表达式为：
Figure PCTCN2021141501-appb-000014
当所述的伺服控制单元工作在锁定状态时Ve→0,表达式进一步可以写为：
Figure PCTCN2021141501-appb-000015
4)另一部分所述的E 3信号经过所述的第六光耦合器后被分为两路：一路经 过所述的第一光锁相单元后输出的信号记为E 7，另一路经过所述的第二光锁相单元后输出的信号记为E 8,所述的E 7和E 8信号的表达式分别为：
Figure PCTCN2021141501-appb-000016
Figure PCTCN2021141501-appb-000017
式中，ω RF3和
Figure PCTCN2021141501-appb-000018
分别表示所述的第三微波源输出射频信号的角频率和初始相位，所述的E 7和E 8信号经所述的第七光耦合器合束后，经所述的第三光电转换单元以及所述的第三电滤波器滤波后输出信号的表达式为：
Figure PCTCN2021141501-appb-000019
将
Figure PCTCN2021141501-appb-000020
的表达式代入到上式，所述的E 9表达式可以进一步改写为：
Figure PCTCN2021141501-appb-000021
另一方面本发明还提供一种分布式光学毫米波/太赫兹传递系统，其特点在于，包括本地端、传递链路、用户端和接入端：
所述的本地端包括光隔离器单元、第一光耦合器、第一法拉第旋转镜、第二光耦合器、第一光滤波器、第二光滤波器、第一声光移频器、第一微波源(17)、第二声光移频器(18)、第三光耦合器、第三光滤波器、第四光滤波器(21)、第一光电转换单元(22)、第二光电转换单元(23)、第一电滤波器(24)、第二电滤波器(25)、第一混频器(26)、伺服控制单元(27)、压控振荡器(28)和第四光耦合器(29)；
所述的用户端(3)包括第三声光移频器(30)、第二微波源(31)、第五光耦合器(32)、第二法拉第旋转镜(33)、第六光耦合器(34)、第三微波源(35)、第一光锁相单元(36)、微波功分器(37)、第二光锁相单元(38)、第七光耦合器(39)、第三光电转换单元(40)和第三电滤波器(41)；
待传光载毫米波信号E 0经依次经光隔离器(10)和第一光耦合器(11)后分为两路，其中一路经第一法拉第旋转镜(12)反射后，返回所述的第一光耦合器(11)作为本地参考光信号E 0输入到所述的第三光耦合器(19)；另一路经所述的第二光耦合(13)再次分为二路，分别经第一光滤波器(14)和第一声光移频器(16)，以及第二光滤波器(15)和第二声光移频器(18)输出，二路信号E 1、E 2经所述的第四光耦合器(29)合束后，经所述的传递链路(2)传递到达用户端(3)；
在所述的用户端(3)依次经所述的第三声光移频器(30)和所述的第五光耦合器(32)后信号E 3被分为两部分，其中一部分经所述的第二法拉第旋转镜(33)反射后，经所述的传递链路(2)传递到本地端(1)，再次经第四光耦合器(29)分束后，沿原路返回，经所述的第二光耦合器(13)合束后，经第一光耦合器(11) 的3端口输入，4端口输出后，与本地参考光一起输入所述的第三光耦合器(19)，经第三光耦合器(19)再次分为二路，一路依次经所述的第三光滤波器(20)、第一光电转换单元(22)和所述的第一电滤波器(24)后进入所述的第一混频器(26)，另一路依次经所述的第四光滤波器(21)、第二光电转换单元(23)和所述的第二电滤波器(25)后进入所述的第一混频器(26)，二路信号经该第一混频器(26)混频取下边带后，输出直流误差信号进入所述的伺服控制单元(27)，驱动所述的压控振荡器(28)实现相位噪声补偿；
另一部分经信号E 3过所述的第六光耦合器(34)后被分为两路，分别进入第一光锁相单元(36)和第二光锁相单元(38)，所述的第三微波源(35)输出射频信号经微波功分器(37)分为二路分别进入第一光锁相单元(36)和第二光锁相单元(38)
将两束光互拍频的信号转换成两束直流信号分别进入所述的第七光耦合器(39)合束后，经所述的第三光电转换单元(40)以及所述的第三电滤波器(41)滤波后即可得到稳定的毫米波信号。
所述的接入端包括第八光耦合器、第九光耦合器、第十光耦合器、第五光滤波器、第四光电转换单元、第四电滤波器、第一分频器单元、第六光滤波器、第五光电转换单元、第五电滤波器、第二分频器单元、第七光滤波器、第四声光移频器、第八光滤波器、第五声光移频器、第十一光耦合器、第六光电转换单元和第六电滤波器；
所述的第八光耦合器位于所述的传递链路的任意节点，用于获取前向传递的光信号和后向传递的光信号；所述的前向传递的光信号经所述的第九光耦合器分成三路，第一路通过所述的第十光耦合器与所述的后向传递的光信号合束后分为两部分，一部分依次经所述的第五光滤波器、第四光电转换单元、第四电滤波器和第一分频器单元后加载在所述的第四声光移频；另一部分依次经所述的第六光滤波器、第五光电转换单元、第五电滤波器和第二分频器单元后加载在所述的第五声光移频器；第二路依次经所述的第七光滤波器和第四声光移频器后进入所述的第十一光耦合器，第三路依次经所述的第八光滤波器和所述的第五声光移频器后所述的第十一光耦合器，两路信号经所述的第十一光耦合器合束后，经所述的第六光电转换单元和第六电滤波器后输出稳定的毫米波信号。
所述的传递链路为光纤链路或者自由空间链路，所述的自由空间链路由自由空间光发射模块、接收模块与自由空间链路组成。
利用上述分布式光学毫米波/太赫兹传递系统的传递方法，其特征在于，该方法具体步骤如下：
1)本地端待传递的光载毫米波信号
Figure PCTCN2021141501-appb-000022
其中两个角频率和相位的差值分别与毫米波的频率和相位相匹配，即ω 2-ω 1＝ ω mmW，
Figure PCTCN2021141501-appb-000023
所述的光载毫米波信号E 0经过所述的光隔离器、所述的第一光耦合器后分成两路：一路经过所述的第一法拉第旋转镜反射，再经所述的第一光耦合器后作为本地参考光输入到所述的第三光耦合器上，另一路经所述的第二光耦合后被分为两部分，一部分所述的E 0光信号过所述的第一光滤波器和所述的第一声光移频器后输出的信号记为E 1,另一部分所述的E 0光信号经过所述的第二光滤波器和所述的第二声光移频器后输出的信号记为E 2,所述的E 1和E 2信号表达式为：
Figure PCTCN2021141501-appb-000024
Figure PCTCN2021141501-appb-000025
式中，ω RF1，
Figure PCTCN2021141501-appb-000026
分别为所述的第一声光移频器射频工作的频率和初始相位，ω vco，
Figure PCTCN2021141501-appb-000027
分别为所述的第二声光移频器射频工作的频率和初始相位；
2)所述的E 1、E 2信号经过所述的第四光耦合器合束后进入所述的传递链路，在所述的用户端经过所述的第三声光移频器后，输出信号E 3的表达式为：
Figure PCTCN2021141501-appb-000028
式中，
Figure PCTCN2021141501-appb-000029
和
Figure PCTCN2021141501-appb-000030
分别表示传递链路引入的相位噪声，ω RF2和
Figure PCTCN2021141501-appb-000031
分别为所述的第三声光移频器射频工作的频率和初始相位；
所述的E 3信号经过所述的第五光耦合器被分为两部分：一部分经过所述的第二法拉第旋转镜后反射进入到所述的传递链路，传递到本地端所述的第四光耦合器后，依次经历了与所述的E 1和E 2信号互逆的路径后，经过所述的第一光耦合器的3,4端口，传递到所述的第三光耦合器的1端口，其表达式为：
Figure PCTCN2021141501-appb-000032
3)这里假设前向传递和后向传递的链路噪声相等，所述的E 4信号与所述的本地参考光信号E 0经过所述的第三光耦合器合束后分为两路：一路依次经过所述的第三光滤波器、第一光电转换单元和所述的第一电滤波器后，输出的信号记为E 5，另一路依次经过所述的第四光滤波器、所述的第二光电转换单元和所述的第二电滤波器后，输出的信号记为E 6，所述的E 5和E 6的表达式分别为：
Figure PCTCN2021141501-appb-000033
Figure PCTCN2021141501-appb-000034
所述的E 5和E 6信号通过所述的第一混频器混频取下边带后，输出的直流误差信号Ve进入所述的伺服控制单元，其表达式为：
Figure PCTCN2021141501-appb-000035
当所述的伺服控制单元工作在锁定状态时Ve→0,表达式进一步可以写为：
Figure PCTCN2021141501-appb-000036
4)在所述的用户端，另一部分所述的E 3信号经过所述的第六光耦合器后被分为两路：一路经过所述的第一光锁相单元后，输出的信号记为E 7，另一路经过所述的第二光锁相单元，输出的信号记为E 8，所述的E 7和E 8信号的表达式为：
Figure PCTCN2021141501-appb-000037
Figure PCTCN2021141501-appb-000038
式中，ω RF3和
Figure PCTCN2021141501-appb-000039
分别表示所述的第三微波源输出射频信号的角频率和初始相位，所述的E 7和E 8信号经所述的第七光耦合器合束后，经所述的第三光电转换单元以及所述的第三电滤波器滤波后输出信号的表达式为：
Figure PCTCN2021141501-appb-000040
将
Figure PCTCN2021141501-appb-000041
的表达式代入到上式，所述的E 9表达式可以进一步改写为：
Figure PCTCN2021141501-appb-000042
5)在所述的传递链路的任意节点，通过所述的第八光耦合器获取前向和后向传递的光信号，其表达式为：
Figure PCTCN2021141501-appb-000043
Figure PCTCN2021141501-appb-000044
式中，
Figure PCTCN2021141501-appb-000045
和
Figure PCTCN2021141501-appb-000046
分别为在ω 1和ω 2频率下本地端到接入端传递链路引入的相位噪声，
Figure PCTCN2021141501-appb-000047
和
Figure PCTCN2021141501-appb-000048
分别为在ω 1和ω 2频率下用户端到接入端传递链路引入的相位噪声。
6)所述的E 10信号经所述的第九光耦合器后分成三路，一路通过所述的第十光耦合器与所述的E 11信号合束后分为两部分，一部分经过所述的第五光滤波器、所述的第四光电转换单元、所述的第四电滤波器、所述的第一分频器单元后，输出的信号记为E 12,另一部分经过所述的第六光滤波器、所述的第五光电转换单元、所述的第五电滤波器、所述的第二分频器单元后，输出的信号记为E 13,所述的E 12和E 13信号分别加载在所述的第四声光移频和第五声光移频器上，其表达式为：
Figure PCTCN2021141501-appb-000049
Figure PCTCN2021141501-appb-000050
7)所述的E 10信号另外两路分别经过所述的第七光滤波器，所述的第四声光移频器和所述的第八光滤波器，所述的第五声光移频器，两路信号经所述的第十一光耦合器合束后，其表达式为：
Figure PCTCN2021141501-appb-000051
式中,链路引入的相位噪声存在如下关系
Figure PCTCN2021141501-appb-000052
所述的E 14信号可以进一步改写为：
Figure PCTCN2021141501-appb-000053
当锁相环进入锁定状态后，所述的E 14经所述的第六光电转换单元和第六电滤波器，其输出信号表达式为：
Figure PCTCN2021141501-appb-000054
用户端和任意接入端均可获得稳定的毫米波/太赫兹信号。
本发明的技术效果如下：
1)一方面，无需借助本地参考源与毫米波信号同步即可实现传递链路的相位补偿，同时还有效地抑制了系统中的后向散射噪声。此外还具有补偿范围无限，可靠性高的特点。
2)另一方面，在传递链路中通过光耦合器提取出前向和后向传递的光信号，经过光信号滤波、光电转换、微波滤波、分频以及光学移频处理，实现传递链路的任意位置获得相位稳定的毫米波/太赫兹信号。此外，该方案还具有可靠性高、结构简单、实现成本低的特点。
附图说明
图1是本发明高精度光学毫米波/太赫兹传递系统实施例的结构示意图。
图2是本发明分布式光学毫米波/太赫兹传递系统实施例的结构示意图。
具体实施方式
下面结合实施例和附图对本发明作进一步说明，本实施例以本发明的技术方案为前提进行实施，给出了详细的实施方式和和具体的工作流程，但本发明的保护范围不限于下述的实施例。
请先参阅图1，图1为本发明高精度光学毫米波传递系统实施例的结构示意图，由图可见，本发明高精度光学毫米波传递系统，包括本地端1、传递链路2和用户端3：所述的本地端1包括光隔离器单元10、第一光耦合器11、第一法拉第旋转镜12、第二光耦合器13、第一光滤波器14、第二光滤波器15、第一声光移频器16、第一微波源17、第二声光移频器18、第三光耦合器19、第三光滤波器20、第四光滤波器21、第一光电转换单元22、第二光电转换单元23、第一电滤波器24、第二电滤波器25、第一混频器26、伺服控制单元27、压控振荡器28和第四光耦合器29；所述的用户端3包括第三声光移频器30、第二微波源31、第五光耦合器32、第二法拉第旋转镜33、第六光耦合器34、第三微波源35、第一光锁相单元36、微波功分器37、第二光锁相单元38、第七光耦合器39、第三光电转换单元40和第三电滤波器41；待传光载毫米波信号E 0经依次经光隔离器10和第一光耦合器11后分为两路，其中一路经第一法拉第旋转镜12反射后，返回所述的第一光耦合器11作为本地参考光输入到所述的第三光耦合器19；另一路经所述的第二光耦合器13再次分为二路，分别经第一光滤波器14和第一声光移频器16，以及第二光滤波器15和第二声光移频器18输出，二路信号经所述的第四光耦合器29合束后，经所述的传递链路2传递到达用户端3；在所述的用户端3依次经所述的第三声光移频器30和所述的第五光耦合器32后E 3信号被分为两部分，其中一部分经所述的第二法拉第旋转镜33反射后，经所述的传递链路2传递到本地端1，再次经第四光耦合器29分束后，沿原路返回，经所述的第二光耦合器13合束后，经第一光耦合器11的3端口输入，4端口输出后，与本地参考光一起输入所述的第三光耦合器19，经第三光耦合器19再次分为二路，一路依次经所述的第三光滤波器20、第一光电转换单元22和所述的第一电滤波器24后进入所述的第一混频器26，另一路依次经所述的第四光滤波器21、第二光电转换单元23和所述的第二电滤波器25后进入所述的第一混频器26，二路信号经该第一混频器26混频取下边带后，输出直流误差信号进入所述的伺服控制单元27；另一部分经E 3信号过所述的第六光耦合器34后被分为两路，一路经所述的第一光锁相单元36，另一路经所述的第二光锁相单元38，经光锁相后的两路信号分别进入经所述的第七光耦合器39合束后，经所述的第三光电转换单元40以及所述的第三电滤波器41滤波后即可得到稳定的毫米波信号。
高精度光学毫米波/太赫兹传递方法，具体步骤如下：
1)本地端待传递的光载毫米波信号
Figure PCTCN2021141501-appb-000055
其中，两个角频率和相位的差值分别与毫米波的频率和相位相匹配，即ω 2-ω 1＝ω mmW，
Figure PCTCN2021141501-appb-000056
所述的光载毫米波信号E 0经过所述的光隔离器10、所述的第一光耦合器11后分为两部分：一部分光载毫米波信号E 0经过所述的第一法拉第旋转镜12反射经所述的第一光耦合器11后作为本地参考光输入到所述的第三光耦合器19上，另一部分光载毫米波信号E 0经所述的第二光耦合器13分为两路：一路经过所述的第一光滤波器14和所述的第一声光移频器16后输出的信号记为E 1,另一路经过所述的第二光滤波器15和所述的第二声光移频器18后输出的信号记为E 2,所述的E 1和E 2信号表达式为：
Figure PCTCN2021141501-appb-000057
Figure PCTCN2021141501-appb-000058
式中，ω RF1，
Figure PCTCN2021141501-appb-000059
分别为所述的第一声光移频器16射频工作的频率和初始相位，ω vco，
Figure PCTCN2021141501-appb-000060
分别为所述的第二声光移频器18射频工作的频率和初始相位；
2)所述的E 1、E 2信号经过所述的第四光耦合器29合束后进入所述的传递链路2，在所述的用户端3经过所述的第三声光移频器30后，输出移频信号E 3的表达式为：
Figure PCTCN2021141501-appb-000061
式中，
Figure PCTCN2021141501-appb-000062
和
Figure PCTCN2021141501-appb-000063
分别表示传递链路引入的相位噪声，ω RF2和
Figure PCTCN2021141501-appb-000064
分别为所述的第三声光移频器30射频工作的频率和初始相位；所述的移频信号E 3经过所述的第五光耦合器32被分为两部分：一部分经过所述的第二法拉第旋转镜33后反射进入到所述的传递链路2，传递到所述的第四光耦合器29后，依次经历了与所述的E 1和E 2信号互逆的路径后，经过所述的第一光耦合器11的3,4端口，传递到所述的第三光耦合器19的1端口，其表达式为：
Figure PCTCN2021141501-appb-000065
3)这里假设前向传递和后向传递的链路噪声相等，所述的信号E 4与所述的本地参考光信号E 0经过所述的第三光耦合器19后分为两路：一路依次经过所述的第三光滤波器20、第一光电转换单元22和所述的第一电滤波器24后，输出的信号记为E 5，另一路依次经过所述的第四光滤波器21、所述的第二光电转换单元23和所述的第二电滤波器25后，输出的信号记为E 6，所述的E 5和E 6的表达 式分别为：
Figure PCTCN2021141501-appb-000066
Figure PCTCN2021141501-appb-000067
所述的E 5和E 6信号通过所述的第一混频器26混频取下边带后，输出的直流误差信号Ve进入所述的伺服控制单元27，其表达式为：
Figure PCTCN2021141501-appb-000068
根据环路控制理论，所述的伺服控制单元27通过实时的改变所述的压控振荡器28的频率进而实现链路相位噪的预补偿，当伺服控制单元27工作在锁定状态时，即误差信号为0，Ve→0,表达式进一步可以写为：
Figure PCTCN2021141501-appb-000069
4)另一部分所述的信号E 3经过所述的第六光耦合器34后被分为两路：一路经过所述的第一光锁相单元36后输出的信号记为E 7，另一路经过所述的第二光锁相单元38后输出的信号记为E 8,所述的E 7和E 8信号的表达式分别为：
Figure PCTCN2021141501-appb-000070
Figure PCTCN2021141501-appb-000071
式中，ω RF3和
Figure PCTCN2021141501-appb-000072
分别表示所述的第三微波源35输出射频信号的角频率和初始相位，所述的E 7和E 8信号经所述的第七光耦合器39合束后，经所述的第三光电转换单元40以及所述的第三电滤波器41滤波后输出信号的表达式为：
Figure PCTCN2021141501-appb-000073
将
Figure PCTCN2021141501-appb-000074
的表达式代入到上式，所述的E 9表达式可以进一步改写为：
Figure PCTCN2021141501-appb-000075
本发明通过双外差检测的方式将传递链路相位噪声转换到两个中频信号上处理，将中频信号输入到单载波相位补偿模块完成锁定，即可实现稳定的毫米波信号传递。本发明无需借助本地参考源与毫米波信号同步即可实现传递链路的相位补偿，同时还有效地抑制了系统中的后向散射噪声。此外还具有补偿范围无限，可靠性高的特点。
图2为本发明分布式光学毫米波传递系统实施例的结构示意图，由图可见，本发明高精度光学毫米波传递系统，包括本地端1、传递链路2、用户端3和接入端4：所述的本地端1包括光隔离器单元10、第一光耦合器11、第一法拉第旋转镜12、第二光耦合器13、第一光滤波器14、第二光滤波器15、第一声光移频器16、第一微波源17、第二声光移频器18、第三光耦合器19、第三光滤波器20、第四光滤波器21、第一光电转换单元22、第二光电转换单元23、第一电滤波器(24)、第二电滤波器25、第一混频器26、伺服控制单元27、压控振荡器(28)和第四光耦合器29；
所述的用户端3包括第三声光移频器30、第二微波源31、第五光耦合器32、第二法拉第旋转镜33、第六光耦合器34、第三微波源35、第一光锁相单元36、微波功分器37、第二光锁相单元38、第七光耦合器39、第三光电转换单元40和第三电滤波器41；
待传光载毫米波信号E 0经依次经光隔离器10和第一光耦合器11后分为两路，其中一路经第一法拉第旋转镜12反射后，返回所述的第一光耦合器11作为本地参考光信号E 0输入到所述的第三光耦合器19；另一路经所述的第二光耦合13再次分为二路，分别经第一光滤波器14和第一声光移频器16，以及第二光滤波器15和第二声光移频器18输出，二路信号E 1、E 2经所述的第四光耦合器29合束后，经所述的传递链路2传递到达用户端3；
在所述的用户端3依次经所述的第三声光移频器30和所述的第五光耦合器32后信号E 3被分为两部分，其中一部分经所述的第二法拉第旋转镜33反射后，经所述的传递链路2传递到本地端1，再次经第四光耦合器29分束后，沿原路返回，经所述的第二光耦合器13合束后，经第一光耦合器(11)的3端口输入，4端口输出后，与本地参考光一起输入所述的第三光耦合器(19)，经第三光耦合器(19)再次分为二路，一路依次经所述的第三光滤波器20、第一光电转换单元(22)和所述的第一电滤波器24后进入所述的第一混频器26，另一路依次经所述的第四光滤波器21、第二光电转换单元23和所述的第二电滤波器25后进入所述的第一混频器26，二路信号经该第一混频器26混频取下边带后，输出直流误差信号进入所述的伺服控制单元27，驱动所述的压控振荡器28实现相位噪声补偿；
另一部分经信号E 3过所述的第六光耦合器34后被分为两路，分别进入第一光锁相单元36和第二光锁相单元38，所述的第三微波源35输出射频信号经微波功分器37分为二路分别进入第一光锁相单元36和第二光锁相单元38
将两束光互拍频的信号转换成两束直流信号分别进入所述的第七光耦合器39合束后，经所述的第三光电转换单元40以及所述的第三电滤波器41滤波后即可得 到稳定的毫米波信号。
所述的接入端4包括第八光耦合器42、第九光耦合器43、第十光耦合器44、第五光滤波器45、第四光电转换单元46、第四电滤波器47、第一分频器单元48、第六光滤波器49、第五光电转换单元50、第五电滤波器51、第二分频器单元52、第七光滤波器53、第四声光移频器54、第八光滤波器55、第五声光移频器56、第十一光耦合器57、第六光电转换单元58和第六电滤波器59；
所述的第八光耦合器42位于所述的传递链路2的任意节点，用于获取前向传递的光信号和后向传递的光信号；所述的前向传递的光信号经所述的第九光耦合器43分成三路，第一路通过所述的第十光耦合器44与所述的后向传递的光信号合束后分为两部分，一部分依次经所述的第五光滤波器45、第四光电转换单元46、第四电滤波器47和第一分频器单元48后加载在所述的第四声光移频51；另一部分依次经所述的第六光滤波器49、第五光电转换单元50、第五电滤波器51和第二分频器单元52后加载在所述的第五声光移频器56；第二路依次经所述的第七光滤波器53和第四声光移频器54后进入所述的第十一光耦合器57，第三路依次经所述的第八光滤波器55和所述的第五声光移频器56后所述的第十一光耦合器57，两路信号经所述的第十一光耦合器57合束后，经所述的第六光电转换单元58和第六电滤波器59后输出稳定的毫米波信号。
实施例中，所述的传递链路2由光纤链路构成，本地端1位于传递链路2的一端，接入端位于传递链路的任意位置，用户端4位于传递链路2的另一端。
利用上述的分布式光学毫米波/太赫兹传递系统的毫米波/太赫兹传递方法，其特征在于，该方法具体步骤如下：
1)本地端待传递的光载毫米波信号
Figure PCTCN2021141501-appb-000076
其中两个角频率和相位的差值分别与毫米波的频率和相位相匹配，即ω 2-ω 1＝ω mmW，
Figure PCTCN2021141501-appb-000077
所述的光载毫米波信号E 0经过所述的光隔离器10、所述的第一光耦合器11后分成两路：一路经过所述的第一法拉第旋转镜12反射，再经所述的第一光耦合器11后作为本地参考光输入到所述的第三光耦合器19上，另一路经所述的第二光耦合13后被分为两部分，一部分所述的E 0光信号过所述的第一光滤波器14和所述的第一声光移频器16后输出的信号记为E 1,另一部分所述的E 0光信号经过所述的第二光滤波器15和所述的第二声光移频器18后输出的信号记为E 2,所述的E 1和E 2信号表达式为：
Figure PCTCN2021141501-appb-000078
Figure PCTCN2021141501-appb-000079
式中，ω RF1，
Figure PCTCN2021141501-appb-000080
分别为所述的第一声光移频器16射频工作的频率和初始相位，ω vco，
Figure PCTCN2021141501-appb-000081
分别为所述的第二声光移频器18射频工作的频率和初始相位；
2)所述的E 1、E 2信号经过所述的第四光耦合器29合束后进入所述的传递链路2，在所述的用户端3经过所述的第三声光移频器30后，输出信号E 3的表达式为：
Figure PCTCN2021141501-appb-000082
式中，
Figure PCTCN2021141501-appb-000083
和
Figure PCTCN2021141501-appb-000084
分别表示传递链路引入的相位噪声，ω RF2和
Figure PCTCN2021141501-appb-000085
分别为所述的第三声光移频器30射频工作的频率和初始相位；
所述的E 3信号经过所述的第五光耦合器32被分为两部分：一部分经过所述的第二法拉第旋转镜33后反射进入到所述的传递链路2，传递到本地端所述的第四光耦合器29后，依次经历了与所述的E 1和E 2信号互逆的路径后，经过所述的第一光耦合器11的3,4端口，传递到所述的第三光耦合器19的1端口，其表达式为：
Figure PCTCN2021141501-appb-000086
3)这里假设前向传递和后向传递的链路噪声相等，所述的E 4信号与所述的本地参考光信号E 0经过所述的第三光耦合器19合束后分为两路：一路依次经过所述的第三光滤波器20、第一光电转换单元22和所述的第一电滤波器24后，输出的信号记为E 5，另一路依次经过所述的第四光滤波器21、所述的第二光电转换单元23和所述的第二电滤波器25后，输出的信号记为E 6，所述的E 5和E 6的表达式分别为：
Figure PCTCN2021141501-appb-000087
Figure PCTCN2021141501-appb-000088
所述的E 5和E 6信号通过所述的第一混频器26混频取下边带后，输出的直流误差信号Ve进入所述的伺服控制单元27，其表达式为：
Figure PCTCN2021141501-appb-000089
当所述的伺服控制单元27工作在锁定状态时Ve→0,表达式进一步可以写为：
Figure PCTCN2021141501-appb-000090
4)在所述的用户端3，另一部分所述的E 3信号经过所述的第六光耦合器34后被分为两路：一路经过所述的第一光锁相单元36后，输出的信号记为E 7，另一路经过所述的第二光锁相单元38，输出的信号记为E 8，所述的E 7和E 8信号的表达式为：
Figure PCTCN2021141501-appb-000091
Figure PCTCN2021141501-appb-000092
式中，ω RF3和
Figure PCTCN2021141501-appb-000093
分别表示所述的第三微波源35输出射频信号的角频率和初始相位，所述的E 7和E 8信号经所述的第七光耦合器39合束后，经所述的第三光电转换单元40以及所述的第三电滤波器41滤波后输出信号的表达式为：
Figure PCTCN2021141501-appb-000094
将
Figure PCTCN2021141501-appb-000095
的表达式代入到上式，所述的E 9表达式可以进一步改写为：
Figure PCTCN2021141501-appb-000096
5)在所述的传递链路2的任意节点，通过所述的第八光耦合器42获取前向和后向传递的光信号，其表达式为：
Figure PCTCN2021141501-appb-000097
Figure PCTCN2021141501-appb-000098
式中，
Figure PCTCN2021141501-appb-000099
和
Figure PCTCN2021141501-appb-000100
分别为在ω 1和ω 2频率下本地端1到接入端4传递链路引入的相位噪声，
Figure PCTCN2021141501-appb-000101
和
Figure PCTCN2021141501-appb-000102
分别为在ω 1和ω 2频率下用户端3到接入端4传递链路引入的相位噪声。
6)所述的E 10信号经所述的第九光耦合器43后分成三路，一路通过所述的第十光耦合器44与所述的E 11信号合束后分为两部分，一部分经过所述的第五光滤波器45、所述的第四光电转换单元46、所述的第四电滤波器47、所述的第一分频器单元48后，输出的信号记为E 12,另一部分经过所述的第六光滤波器49、所述的第五光电转换单元50、所述的第五电滤波器51、所述的第二分频器单元52后，输出的信号记为E 13,所述的E 12和E 13信号分别加载在所述的第四声光移频54和第五声光移频器56上，其表达式为：
Figure PCTCN2021141501-appb-000103
Figure PCTCN2021141501-appb-000104
7)所述的E 10信号另外两路分别经过所述的第七光滤波器53，所述的第四声光移频器54和所述的第八光滤波器55，所述的第五声光移频器56，两路信号 经所述的第十一光耦合器57合束后，其表达式为：
Figure PCTCN2021141501-appb-000105
式中,链路引入的相位噪声存在如下关系
Figure PCTCN2021141501-appb-000106
所述的E 14信号可以进一步改写为：
Figure PCTCN2021141501-appb-000107
当锁相环进入锁定状态后，所述的E 14经所述的第六光电转换单元58和第六电滤波器59，其输出信号表达式为：
Figure PCTCN2021141501-appb-000108
用户端和任意接入端均可获得稳定的毫米波/太赫兹信号。
实验表明，本发明在传递链路中通过光耦合器提取出前向和后向传递的光信号，经过光信号滤波、光电转换、微波滤波、分频以及光学移频处理，实现传递链路的任意位置获得相位稳定的毫米波/太赫兹信号。此外，该方案还具有可靠性高、结构简单、实现成本低的特点。

Claims (5)

  1. 一种光学毫米波及太赫兹传递系统，包括本地端(1)、传递链路(2)和用户端(3)，其特征在于，
    所述的本地端(1)包括光隔离器单元(10)、第一光耦合器(11)、第一法拉第旋转镜(12)、第二光耦合器(13)、第一光滤波器(14)、第二光滤波器(15)、第一声光移频器(16)、第一微波源(17)、第二声光移频器(18)、第三光耦合器(19)、第三光滤波器(20)、第四光滤波器(21)、第一光电转换单元(22)、第二光电转换单元(23)、第一电滤波器(24)、第二电滤波器(25)、第一混频器(26)、伺服控制单元(27)、压控振荡器(28)和第四光耦合器(29)；
    所述的用户端(3)包括第三声光移频器(30)、第二微波源(31)、第五光耦合器(32)、第二法拉第旋转镜(33)、第六光耦合器(34)、第三微波源(35)、第一光锁相单元(36)、微波功分器(37)、第二光锁相单元(38)、第七光耦合器(39)、第三光电转换单元(40)和第三电滤波器(41)；
    待传光载毫米波信号E 0经依次经光隔离器(10)和第一光耦合器(11)后分为两路，其中一路经第一法拉第旋转镜(12)反射后，返回所述的第一光耦合器(11)作为本地参考光信号E 0输入到所述的第三光耦合器(19)；另一路经所述的第二光耦合器(13)再次分为二路，分别经第一光滤波器(14)和第一声光移频器(16)，以及第二光滤波器(15)和第二声光移频器(18)输出，二路信号E 1、E 2经所述的第四光耦合器(29)合束后，经所述的传递链路(2)传递到达用户端(3)；
    在所述的用户端(3)依次经所述的第三声光移频器(30)和所述的第五光耦合器(32)后信号E 3被分为两部分，其中一部分经所述的第二法拉第旋转镜(33)反射后，经所述的传递链路(2)传递到本地端(1)，再次经第四光耦合器(29)分束后，沿原路返回，经所述的第二光耦合器(13)合束后，经第一光耦合器(11)的3端口输入，4端口输出后，与本地参考光一起输入所述的第三光耦合器(19)，经第三光耦合器(19)再次分为二路，一路依次经所述的第三光滤波器(20)、第一光电转换单元(22)和所述的第一电滤波器(24)后进入所述的第一混频器(26)，另一路依次经所述的第四光滤波器(21)、第二光电转换单元(23)和所述的第二电滤波器(25)后进入所述的第一混频器(26)，二路信号经该第一混频器(26)混频取下边带后，输出直流误差信号进入所述的伺服控制单元(27)，驱动所述的压控振荡器(28)实现相位噪声补偿；
    另一部分E 3信号经过所述的第六光耦合器(34)后被分为两路，分别进入第一光锁相单元(36)和第二光锁相单元(38)，所述的第三微波源(35)输出射频信号经微波功分器(37)分为二路分别进入第一光锁相单元(36)和第二光锁相单元(38)，将两束光锁相后的信号分别进入所述的第七光耦合器(39)合束后，经所 述的第三光电转换单元(40)以及所述的第三电滤波器(41)滤波后即可得到稳定的毫米波信号。
  2. 根据权利要求1所述的光学毫米波及太赫兹传递系统，其特征在于，还包括接入端(4)；
    所述的接入端(4)包括第八光耦合器(42)、第九光耦合器(43)、第十光耦合器(44)、第五光滤波器(45)、第四光电转换单元(46)、第四电滤波器(47)、第一分频器单元(48)、第六光滤波器(49)、第五光电转换单元(50)、第五电滤波器(51)、第二分频器单元(52)、第七光滤波器(53)、第四声光移频器(54)、第八光滤波器(55)、第五声光移频器(56)、第十一光耦合器(57)、第六光电转换单元(58)和第六电滤波器(59)；
    所述的第八光耦合器(42)位于所述的传递链路(2)的任意节点，用于获取前向传递的光信号和后向传递的光信号；所述的前向传递的光信号经所述的第九光耦合器(43)分成三路，第一路通过所述的第十光耦合器(44)与所述的后向传递的光信号合束后分为两部分，一部分依次经所述的第五光滤波器(45)、第四光电转换单元(46)、第四电滤波器(47)和第一分频器单元(48)后加载在所述的第四声光移频(51)；另一部分依次经所述的第六光滤波器(49)、第五光电转换单元(50)、第五电滤波器(51)和第二分频器单元(52)后加载在所述的第五声光移频器(56)；第二路依次经所述的第七光滤波器(53)和第四声光移频器(54)后进入所述的第十一光耦合器(57)，第三路依次经所述的第八光滤波器(55)和所述的第五声光移频器(56)后进入所述的第十一光耦合器(57)，两路信号经所述的第十一光耦合器(57)合束后，经所述的第六光电转换单元(58)和第六电滤波器(59)后输出稳定的毫米波信号。
  3. 根据权利要求1或2所述的分布式光学毫米波/太赫兹传递系统，其特征在于，所述的传递链路(2)为光纤链路或者自由空间链路，所述的自由空间链路由自由空间光发射模块、接收模块与自由空间链路组成。
  4. 利用权利要求1所述的光学毫米波/太赫兹传递系统的毫米波/太赫兹传递方法，其特征在于，该方法具体步骤如下：
    S1.本地端待传递的光载毫米波信号为
    Figure PCTCN2021141501-appb-100001
    其中两个角频率和相位的差值分别与毫米波的频率和相位相匹配，即
    Figure PCTCN2021141501-appb-100002
    Figure PCTCN2021141501-appb-100003
    所述的待传光载毫米波信号E 0经过所述的光隔离器(10)和所述的第一光耦合器(11)后分为两部分：一部分待传光载毫米波信号E 0经过所述的第一法拉第旋转镜(12)反射，返回至所述的第一光耦合器(11)，经所述的第一光耦合器(11)后作为本地参考光输入到所述的第三光耦合器(19)上，另一部分待传光载毫米波信号E 0经所述的第二光耦合器(13)分为两路后，一路经过所述的第一光滤波器(14)和所述的第一声光移频器(16)后输出的信号E 1,另一路 经过所述的第二光滤波器(15)和所述的第二声光移频器(18)后输出的信号E 2,所述的信号E 1和信号E 2表达式为：
    Figure PCTCN2021141501-appb-100004
    Figure PCTCN2021141501-appb-100005
    式中，ω RF1，
    Figure PCTCN2021141501-appb-100006
    分别为所述的第一声光移频器(16)射频工作的频率和初始相位，ω vco，
    Figure PCTCN2021141501-appb-100007
    分别为所述的第二声光移频器(18)射频工作的频率和初始相位；ω RF1＝ω c，
    S2.信号E 1和信号E 2经过所述的第四光耦合器(29)合束后经传递链路(2)到达用户端(3)，经第三声光移频器(30)输出信号E 3，表达式为：
    Figure PCTCN2021141501-appb-100008
    式中，
    Figure PCTCN2021141501-appb-100009
    和
    Figure PCTCN2021141501-appb-100010
    分别表示传递链路引入的相位噪声，ω RF2和
    Figure PCTCN2021141501-appb-100011
    分别为第三声光移频器(30)射频工作的频率和初始相位；
    所述的信号E 3经第五光耦合器(32)分为两部分：一部分信号E 3经第二法拉第旋转镜(33)反射后，经所述的传递链路(2)传递到本地端(1)的第四光耦合器(29)，并经历与所述的信号E 1和信号E 2互逆的路径后，由所述的第一光耦合器(11)的3端口输入、4端口输出信号，并传递到所述的第三光耦合器(19)的1端口，信号E 4，表达式为：
    Figure PCTCN2021141501-appb-100012
    S3.设前向传递和后向传递的链路噪声相等，所述的信号E 4与所述的本地参考光信号E 0经过所述的第三光耦合器(19)后分为两路：一路依次经过所述的第三光滤波器(20)、第一光电转换单元(22)和所述的第一电滤波器(24)后，输出的信号E 5，另一路依次经过所述的第四光滤波器(21)、所述的第二光电转换单元(23)和所述的第二电滤波器(25)后，输出的信号E 6，表达式分别为：
    Figure PCTCN2021141501-appb-100013
    Figure PCTCN2021141501-appb-100014
    所述的信号E 5和E 6通过所述的第一混频器(26)混频取下边带后，输出的直流误差信号Ve，进入所述的伺服控制单元(27)，其表达式为：
    Figure PCTCN2021141501-appb-100015
    当所述的伺服控制单元(27)工作在锁定状态时Ve→0,则：
    Figure PCTCN2021141501-appb-100016
    S4.另一部分信号E 3经过所述的第六光耦合器(34)分为两路：一路经过所述的第一光锁相单元(36)输出信号E 7，另一路经第二光锁相单元(38)输出信号E 8,表达式分别为：
    Figure PCTCN2021141501-appb-100017
    Figure PCTCN2021141501-appb-100018
    式中，ω RF3和
    Figure PCTCN2021141501-appb-100019
    分别表示第三微波源(35)输出射频信号的角频率和初始相位；信号E 7和信号E 8经所述的第七光耦合器(39)合束后，经第三光电转换单元(40)和第三电滤波器(41)滤波后输出信号E 9,表达式为：
    Figure PCTCN2021141501-appb-100020
    将
    Figure PCTCN2021141501-appb-100021
    的表达式代入到上式，信号E 9为：
    Figure PCTCN2021141501-appb-100022
  5. 利用权利要求2所述的光学毫米波/太赫兹传递系统的毫米波/太赫兹传递方法，其特征在于，该方法具体步骤如下：
    1)本地端待传递的光载毫米波信号
    Figure PCTCN2021141501-appb-100023
    其中两个角频率和相位的差值分别与毫米波的频率和相位相匹配，即ω 2-ω 1＝ω mmW，
    Figure PCTCN2021141501-appb-100024
    所述的光载毫米波信号E 0经过所述的光隔离器(10)、所述的第一光耦合器(11)后分成两路：一路经过所述的第一法拉第旋转镜(12)反射，再经所述的第一光耦合器(11)后作为本地参考光输入到所述的第三光耦合器(19)上，另一路经所述的第二光耦合(13)后被分为两部分，一部分所述的E 0光信号过所述的第一光滤波器(14)和所述的第一声光移频器(16)后输出的信号记为E 1,另一部分所述的E 0光信号经过所述的第二光滤波器(15)和所述的第二声光移频器(18)后输出的信号记为E 2,所述的E 1和E 2信号表达式为：
    Figure PCTCN2021141501-appb-100025
    Figure PCTCN2021141501-appb-100026
    式中，ω RF1，
    Figure PCTCN2021141501-appb-100027
    分别为所述的第一声光移频器(16)射频工作的频率和初始相位，ω vco，
    Figure PCTCN2021141501-appb-100028
    分别为所述的第二声光移频器(18)射频工作的频率和初始相位；
    2)所述的E 1、E 2信号经过所述的第四光耦合器(29)合束后进入所述的传递链路(2)，在所述的用户端(3)经过所述的第三声光移频器(30)后，输出信号E 3的表达式为：
    Figure PCTCN2021141501-appb-100029
    式中，
    Figure PCTCN2021141501-appb-100030
    和
    Figure PCTCN2021141501-appb-100031
    分别表示传递链路引入的相位噪声，ω RF2和
    Figure PCTCN2021141501-appb-100032
    分别为所述的第三声光移频器(30)射频工作的频率和初始相位；
    所述的E 3信号经过所述的第五光耦合器(32)被分为两部分：一部分经过所述的第二法拉第旋转镜(33)后反射进入到所述的传递链路(2)，传递到本地端所述的第四光耦合器(29)后，依次经历了与所述的E 1和E 2信号互逆的路径后，经过所述的第一光耦合器(11)的3,4端口，传递到所述的第三光耦合器(19)的1端口，其表达式为：
    Figure PCTCN2021141501-appb-100033
    3)设前向传递和后向传递的链路噪声相等，所述的E 4信号与所述的本地参考光信号E 0经过所述的第三光耦合器(19)合束后分为两路：一路依次经过所述的第三光滤波器(20)、第一光电转换单元(22)和所述的第一电滤波器(24)后，输出的信号记为E 5，另一路依次经过所述的第四光滤波器(21)、所述的第二光电转换单元(23)和所述的第二电滤波器(25)后，输出的信号记为E 6，所述的E 5和E 6的表达式分别为：
    Figure PCTCN2021141501-appb-100034
    Figure PCTCN2021141501-appb-100035
    所述的E 5和E 6信号通过所述的第一混频器(26)混频取下边带后，输出的直流误差信号Ve进入所述的伺服控制单元(27)，其表达式为：
    Figure PCTCN2021141501-appb-100036
    当所述的伺服控制单元(27)工作在锁定状态时Ve→0,表达式进一步可以写为：
    Figure PCTCN2021141501-appb-100037
    4)在所述的用户端(3)，另一部分所述的E 3信号经过所述的第六光耦合器(34)后被分为两路：一路经过所述的第一光锁相单元(36)后，输出的信号记为E 7，另一路经过所述的第二光锁相单元(38)，输出的信号记为E 8，所述的E 7和E 8信号的表达式为：
    Figure PCTCN2021141501-appb-100038
    Figure PCTCN2021141501-appb-100039
    式中，ω RF3和
    Figure PCTCN2021141501-appb-100040
    分别表示所述的第三微波源(35)输出射频信号的角频率和初始相位，所述的E 7和E 8信号经所述的第七光耦合器(39)合束后，经所述的第三光电转换单元(40)以及所述的第三电滤波器(41)滤波后输出信号的表达式为：
    Figure PCTCN2021141501-appb-100041
    将
    Figure PCTCN2021141501-appb-100042
    的表达式代入到上式，所述的E 9表达式可以进一步改写为：
    Figure PCTCN2021141501-appb-100043
    5)在所述的传递链路(2)的任意节点，通过所述的第八光耦合器(42)获取前向和后向传递的光信号，其表达式为：
    Figure PCTCN2021141501-appb-100044
    Figure PCTCN2021141501-appb-100045
    式中，
    Figure PCTCN2021141501-appb-100046
    和
    Figure PCTCN2021141501-appb-100047
    分别为在ω 1和ω 2频率下本地端(1)到接入端(4)传递链路引入的相位噪声，
    Figure PCTCN2021141501-appb-100048
    和
    Figure PCTCN2021141501-appb-100049
    分别为在ω 1和ω 2频率下用户端(3)到接入端(4)传递链路引入的相位噪声。
    6)所述的E 10信号经所述的第九光耦合器(43)后分成三路，一路通过所述的第十光耦合器(44)与所述的E 11信号合束后分为两部分，一部分经过所述的第五光滤波器(45)、所述的第四光电转换单元(46)、所述的第四电滤波器(47)、所述的第一分频器单元(48)后，输出的信号记为E 12,另一部分经过所述的第六光滤波器(49)、所述的第五光电转换单元(50)、所述的第五电滤波器(51)、所述的第二分频器单元(52)后，输出的信号记为E 13,所述的E 12和E 13信号分别加载在所述的第四声光移频(54)和第五声光移频器(56)上，其表达式为：
    Figure PCTCN2021141501-appb-100050
    Figure PCTCN2021141501-appb-100051
    7)所述的E 10信号另外两路分别经过所述的第七光滤波器(53)，所述的第四声光移频器(54)和所述的第八光滤波器(55)，所述的第五声光移频器(56)，两路信号经所述的第十一光耦合器(57)合束后，其表达式为：
    Figure PCTCN2021141501-appb-100052
    式中,链路引入的相位噪声存在如下关系
    Figure PCTCN2021141501-appb-100053
    所述的E 14信号可以进一步改写为：
    Figure PCTCN2021141501-appb-100054
    当锁相环进入锁定状态后，所述的E 14经所述的第六光电转换单元(58)和第六电滤波器(59)，其输出信号表达式为：
    Figure PCTCN2021141501-appb-100055
    用户端和任意接入端均可获得稳定的毫米波/太赫兹信号。
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Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102215104A (zh) * 2011-05-31 2011-10-12 上海交通大学 基于延迟锁相环的微波信号远距离稳相光纤传输装置
CN103684611A (zh) * 2013-12-04 2014-03-26 上海交通大学 一种相位稳定的毫米波生成系统及方法
US20170292875A1 (en) * 2014-10-02 2017-10-12 Gwangju Institute Of Science And Technology Device for generating and detecting photo mixing-type continuous-wave terahertz using phase noise compensation method
CN110061778A (zh) * 2019-04-08 2019-07-26 上海交通大学 光纤微波与光学频率同时传递装置与传递方法
CN111147150A (zh) * 2019-12-18 2020-05-12 上海交通大学 基于被动相位补偿的分布式光学频率传递装置与传递方法
CN111181648A (zh) * 2019-12-23 2020-05-19 上海交通大学 基于被动相位补偿的微波频率传递装置及传递方法
CN112821956A (zh) * 2020-12-29 2021-05-18 网络通信与安全紫金山实验室 一种太赫兹信号的生成方法及装置

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102215104A (zh) * 2011-05-31 2011-10-12 上海交通大学 基于延迟锁相环的微波信号远距离稳相光纤传输装置
CN103684611A (zh) * 2013-12-04 2014-03-26 上海交通大学 一种相位稳定的毫米波生成系统及方法
US20170292875A1 (en) * 2014-10-02 2017-10-12 Gwangju Institute Of Science And Technology Device for generating and detecting photo mixing-type continuous-wave terahertz using phase noise compensation method
CN110061778A (zh) * 2019-04-08 2019-07-26 上海交通大学 光纤微波与光学频率同时传递装置与传递方法
CN111147150A (zh) * 2019-12-18 2020-05-12 上海交通大学 基于被动相位补偿的分布式光学频率传递装置与传递方法
CN111181648A (zh) * 2019-12-23 2020-05-19 上海交通大学 基于被动相位补偿的微波频率传递装置及传递方法
CN112821956A (zh) * 2020-12-29 2021-05-18 网络通信与安全紫金山实验室 一种太赫兹信号的生成方法及装置

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
DELMADE AMOL; BROWNING COLM; VEROLET THEO; POETTE JULIEN; FARHANG ARMAN; ELWAN HAMZA HALLAK; KOILPILLAI R DAVID; AUBIN GUY; LELARG: "Optical Heterodyne Analog Radio-Over-Fiber Link for Millimeter-Wave Wireless Systems", JOURNAL OF LIGHTWAVE TECHNOLOGY, IEEE, USA, vol. 39, no. 2, 21 October 2020 (2020-10-21), USA, pages 465 - 474, XP011827402, ISSN: 0733-8724, DOI: 10.1109/JLT.2020.3032923 *
MAN, XIAOJING ET AL.: "Phase Stabilized Distribution of Millimeter Wave Local Oscillator Based on Michelson Interferometer", ACTA OPTICA SINICA, vol. 30, no. 8, 31 August 2010 (2010-08-31), XP009547142 *

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