Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
DETAILED OFFICE ACTION
Status of Claims
Claims 1-10 are pending examination.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries set forth in Graham v. John Deere Co., 383 U.S. 1, 148 USPQ 459 (1966), that are applied for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b) (2) (C) for any potential 35 U.S.C. 102(a) (2) prior art against the later invention.
1. Claims 1,2,3 and 10 are rejected under 35 U.S.C 103(a) as being unpatentable over Younce et al. ( USPUB 20200382217 ) in view of Jose Krause Perin et al.(NPL Doc: " Coherent Data Center Links," 2nd February 2021, JOURNAL OF LIGHTWAVE TECHNOLOGY, VOL. 39, NO. 3, FEBRUARY 1, 2021,Pages 730-739.).
As per claim 1, Younce et al. teaches An apparatus for determining an optical phase difference of a sub-signal of an optical transmitter ( FIG. 6 and Paragraph [0060-0061]- “…f a switchable Mach-Zehnder interferometer (MZI) having a tunable phase shifter 341 in one of its arms to effect the switching. In some embodiments input switches 321, 322 may be replaced by optical splitters, as illustrated in FIG. 9. Each of the two single-channels PCs 361 and 362 includes two 2×2 directional couplers 330 connected in series and two tunable phase shifters, such as phase-shifters 371, 372 in PC 361 or phase shifter 373, 374 in PC 362. One of the single-channel PCs 362 or 361 may include an additional coupler at its input. To account for the phase shift associated with differences in the optical path between PC 361 and PC 362…”) , comprising: a memory; and a processor coupled to the memory ( Paragraph [0003]- “… This signal processing may be relatively complex and thus typically requires digital signal processors (DSPs) that are relatively power-consuming and expansive….” AND Paragraph [0053]- “… further processing and/or extracting the data signal that was used at the transmitter to modulate the optical signal…”) to: input a first input signal to a first electro-optical conversion unit, to enable the first electro-optical conversion unit to modulate to-be-modulated light according to the first input signal and to obtain a first output signal ( FIG. 12 AND Paragraphs [0068-0069]- “… optical transmitter 870 that is configured to transmit four data channels over a single optical fiber by wavelength multiplexing two PM channels. A data source 879 provides four electrical drive signals, each carrying a respective signal subchannel, to four MZMs 881-884 to modulate light propagating therein in amplitude. Light from a first laser 871 emitting at a first wavelength λ1 is split and fed in parallel into a first MZM 881 and a second MZM 882. Light from a second laser 872 emitting at a second wavelength λ2 is split and fed in parallel into a third MZM 883 and a fourth MZM 884. Outputs of the first and third MZMs 881, 883 are wavelength multiplexed using a first wavelength multiplexer (MUX) 875, while outputs of the second and fourth MZMs 882, 884 are wavelength multiplexed using a second wavelength MUX 876. In the illustrated embodiment the optical MUXs 875, 876 are embodied with waveguide MZIs; …”) ;
input a second input signal to a second electro-optical conversion unit, to enable the second electro-optical conversion unit to modulate to-be-modulated light according to the second input signal and to obtain a second output signal ( Paragraphs [0068-0070]- “… to four MZMs 881-884 to modulate light propagating therein in amplitude. Light from a first laser 871 emitting at a first wavelength λ1 is split and fed in parallel into a first MZM 881 and a second MZM 882. Light from a second laser 872 emitting at a second wavelength λ2 is split and fed in parallel into a third MZM 883 and a fourth MZM 884. Outputs of the first and third MZMs 881, 883 are wavelength multiplexed using a first wavelength multiplexer (MUX) 875, while outputs of the second and fourth MZMs 882, 884 are wavelength multiplexed using a second wavelength MUX 876. In the illustrated embodiment the optical MUXs 875, 876 are embodied with waveguide MZIs; …”) , wherein correlation of the second input signal and the first input signal is not 0 ( Paragraphs [0051-0052]- “… modulation format of the received signal light 101 may, for example, be OOK/NRZ (On-Off Keyed Non Return to Zero), OOK RZ (Return to Zero), PAM4 (Pulse Amplitude Modulated 4 level), or a higher level PAM format. The description hereinbelow may refer to PAM4 for clarity, but the approaches, techniques and structures described herein may be used in application to other modulation formats….”) ;
Younce et al. does not explicitly teach perform a coherent detection operation based on the first output signal and the second output signal to obtain a first output quantity and a second output quantity; and determine an optical phase difference of an output signal of the first electro-optical conversion unit and an output signal of the second electro-optical conversion unit according to the first output quantity and the second output quantity.
However,within analogous art, Jose Krause Perin et al. teaches perform a coherent detection operation based on the first output signal and the second output signal to obtain a first output quantity and a second output quantity (Page 736-Fig. 5 teaches coherent detection AND Page 734- Col. 2- “…perform a coherent detection operation based on the first output signal and the second output signal to obtain a first output quantity and a second output quantity; and determine an optical phase difference of an output signal of the first electro-optical conversion unit and an output signal of the second electro-optical conversion unit according to the first output quantity and the second output quantity….” ) ; and determine an optical phase difference of an output signal of the first electro-optical conversion unit and an output signal of the second electro-optical conversion unit according to the first output quantity and the second output quantity (Fig. 2 and Fig. 6 AND Page 733-Col. 2- “…Differentially coherent detection is performed in practice by estimating the phase difference between two or more consecutive symbols. This precludes the need of an absolute phase reference, and hence carrier phase recovery is not necessary. Differential detection, however, has two main disadvantages compared to coherent detection. First, for the same spectral efficiency, differential detection has an inherent SNR penalty, e.g., about 2.4 dB for DQPSK compared to QPSK [2]. Second, differential detection restricts modulation to PSK formats. The estimation of the phase difference between two consecutive symbols may be realized in the optical domain…” AND Page 734-Col. 1- “…Differential detection may also be performed in the electrical domain with an LO laser. Fig. 2 b shows one implementation of differentially coherent detection, whereby the phase difference between two symbols is realized in the electrical domain….”).
One of ordinary skill in the art would have been motivated to combine the teaching of Jose Krause Perin et al. within the modified teaching of the Coherent optical receiver mentioned by Younce et al. because the Coherent Data Center Links mentioned by Jose Krause Perin et al. provides a method and system for implementation of co-packaging optical transceivers with electrical switches for optical signal processing.
Therefore, it would have been obvious for one in the ordinary skills in the art before the effective filing date of the claimed invention to the Coherent Data Center Links mentioned by Jose Krause Perin et al. within the modified teaching of the Coherent optical receiver mentioned by Younce et al. for implementation of co-packaging optical transceivers with electrical switches for optical signal processing.
As per claim 2, Combination of Younce et al. and Jose Krause Perin et al. teach claim 1,
Younce et al. teaches wherein the first electro-optical conversion unit is a transmitter, or a partial modulation unit of the transmitter ( MZM ( EO modulator ) in transmitter taught within Fig. 4 and Paragraph [0057]- “…FIG. 4, in the optical transmitter 270 two separate drive signals, which carry data signals of two different transmit channels, are provided from two data sources 272 to two optical modulators 278. The optical modulators 278 may be for example two MZMs configured to output two light signals that are modulated in amplitude or, equivalently, in intensity. A same TX laser 274 may be used as the light source for both optical modulators 278….”) .
As per claim 3, Combination of Younce et al. and Jose Krause Perin et al. teach claim 1,
Younce et al. teaches wherein the second electro-optical conversion unit outputs a finite number of states ( Paragraph [0057]- “…A same TX laser 274 may be used as the light source for both optical modulators 278. Alternatively, two different sources of coherent light may be used. The AM light signals from the outputs of the two optical modulators 278 may then be polarization multiplexed, i.e. combined in orthogonal polarizations, using a polarization combiner 279 to produce PMAM signal light 201 in the form of a single beam of light. The PMAM signal light 201 carries information in two TX-defined polarization channels, which may be referred to herein as a first PM Channel (PCh1) and a second PM channel (PCh2)….”) .
As per claim 10, Younce et al. teaches A method for determining an optical phase difference of a sub-signal of an optical transmitter ( FIG. 6 and Paragraph [0060-0061]- “…f a switchable Mach-Zehnder interferometer (MZI) having a tunable phase shifter 341 in one of its arms to effect the switching. In some embodiments input switches 321, 322 may be replaced by optical splitters, as illustrated in FIG. 9. Each of the two single-channels PCs 361 and 362 includes two 2×2 directional couplers 330 connected in series and two tunable phase shifters, such as phase-shifters 371, 372 in PC 361 or phase shifter 373, 374 in PC 362. One of the single-channel PCs 362 or 361 may include an additional coupler at its input. To account for the phase shift associated with differences in the optical path between PC 361 and PC 362…”) , comprising: the method comprising: inputting a first input signal to a first electro-optical conversion unit, to enable the first electro-optical conversion unit to modulate to-be-modulated light according to the first input signal and to obtain a first output signal ( FIG. 12 AND Paragraphs [0068-0069]- “… optical transmitter 870 that is configured to transmit four data channels over a single optical fiber by wavelength multiplexing two PM channels. A data source 879 provides four electrical drive signals, each carrying a respective signal subchannel, to four MZMs 881-884 to modulate light propagating therein in amplitude. Light from a first laser 871 emitting at a first wavelength λ1 is split and fed in parallel into a first MZM 881 and a second MZM 882. Light from a second laser 872 emitting at a second wavelength λ2 is split and fed in parallel into a third MZM 883 and a fourth MZM 884. Outputs of the first and third MZMs 881, 883 are wavelength multiplexed using a first wavelength multiplexer (MUX) 875, while outputs of the second and fourth MZMs 882, 884 are wavelength multiplexed using a second wavelength MUX 876. In the illustrated embodiment the optical MUXs 875, 876 are embodied with waveguide MZIs; …”) ;inputting a second input signal to a second electro-optical conversion unit, to enable the second electro-optical conversion unit to modulate to-be-modulated light according to the second input signal and to obtain a second output signal ( Paragraphs [0068-0070]- “… to four MZMs 881-884 to modulate light propagating therein in amplitude. Light from a first laser 871 emitting at a first wavelength λ1 is split and fed in parallel into a first MZM 881 and a second MZM 882. Light from a second laser 872 emitting at a second wavelength λ2 is split and fed in parallel into a third MZM 883 and a fourth MZM 884. Outputs of the first and third MZMs 881, 883 are wavelength multiplexed using a first wavelength multiplexer (MUX) 875, while outputs of the second and fourth MZMs 882, 884 are wavelength multiplexed using a second wavelength MUX 876. In the illustrated embodiment the optical MUXs 875, 876 are embodied with waveguide MZIs; …”) , wherein correlation of the second input signal and the first input signal is not 0 ( Paragraphs [0051-0052]- “… modulation format of the received signal light 101 may, for example, be OOK/NRZ (On-Off Keyed Non Return to Zero), OOK RZ (Return to Zero), PAM4 (Pulse Amplitude Modulated 4 level), or a higher level PAM format. The description hereinbelow may refer to PAM4 for clarity, but the approaches, techniques and structures described herein may be used in application to other modulation formats….”) ;
Younce et al. does not explicitly teach performing a coherent detection operation based on the first output signal and the second output signal to obtain a first output quantity and a second output quantity; and determining an optical phase difference of an output signal of the first electro-optical conversion unit and an output signal of the second electro-optical conversion unit according to the first output quantity and the second output quantity.
However,within analogous art, Jose Krause Perin et al. teaches teach performing a coherent detection operation based on the first output signal and the second output signal to obtain a first output quantity and a second output quantity (Page 736-Fig. 5 teaches coherent detection AND Page 734- Col. 2- “…perform a coherent detection operation based on the first output signal and the second output signal to obtain a first output quantity and a second output quantity; and determine an optical phase difference of an output signal of the first electro-optical conversion unit and an output signal of the second electro-optical conversion unit according to the first output quantity and the second output quantity….” ) ; and determining an optical phase difference of an output signal of the first electro-optical conversion unit and an output signal of the second electro-optical conversion unit according to the first output quantity and the second output quantity (Fig. 2 and Fig. 6 AND Page 733-Col. 2- “…Differentially coherent detection is performed in practice by estimating the phase difference between two or more consecutive symbols. This precludes the need of an absolute phase reference, and hence carrier phase recovery is not necessary. Differential detection, however, has two main disadvantages compared to coherent detection. First, for the same spectral efficiency, differential detection has an inherent SNR penalty, e.g., about 2.4 dB for DQPSK compared to QPSK [2]. Second, differential detection restricts modulation to PSK formats. The estimation of the phase difference between two consecutive symbols may be realized in the optical domain…” AND Page 734-Col. 1- “…Differential detection may also be performed in the electrical domain with an LO laser. Fig. 2 b shows one implementation of differentially coherent detection, whereby the phase difference between two symbols is realized in the electrical domain….”) .
One of ordinary skill in the art would have been motivated to combine the teaching of Jose Krause Perin et al. within the modified teaching of the Coherent optical receiver mentioned by Younce et al. because the Coherent Data Center Links mentioned by Jose Krause Perin et al. provides a method and system for implementation of co-packaging optical transceivers with electrical switches for optical signal processing.
Therefore, it would have been obvious for one in the ordinary skills in the art before the effective filing date of the claimed invention to the Coherent Data Center Links mentioned by Jose Krause Perin et al. within the modified teaching of the Coherent optical receiver mentioned by Younce et al. for implementation of co-packaging optical transceivers with electrical switches for optical signal processing.
2. Claim 9 is rejected under 35 U.S.C 103(a) as being unpatentable over Younce et al. ( USPUB 20200382217 ) in view of Jose Krause Perin et al.(NPL Doc: " Coherent Data Center Links," 2nd February 2021, JOURNAL OF LIGHTWAVE TECHNOLOGY, VOL. 39, NO. 3, FEBRUARY 1, 2021,Pages 730-739.) in further view of ZHANG et al. ( USPUB 20190165864).
As per claim 9, Combination of Younce et al. and Jose Krause Perin et al. teach claim 1,
Combination of Younce et al. and Jose Krause Perin et al. does not explicitly teach wherein the processor is further configured to: pre-set input, at a pre-set moment, the second input signal to the second electro-optical conversion unit; and input, at a moment other than the pre-set moment, a signal with correlation of 0 with the first input signal, or a 0 signal to the second electro-optical conversion unit.
Within analogous art , ZHANG et al. teaches wherein the processor is further configured to: pre-set input, at a pre-set moment, the second input signal to the second electro-optical conversion unit ( Controller / processor ( 350) taught within Paragraph [0042-0043]- “…output by tributary modulator 330. In some implementations, controller 350 may maintain a bias of tributary modulator 330 at a particular transmission and/or bias point (e.g., a null (minimum) transmission and/or bias point, a quadrature (half) transmission and/or bias point, a full (maximum) transmission and/or bias point, etc.) associated with tributary modulator 330 using a feedback loop. For example, controller 350 may ensure that the output of tributary modulator 330 is zero (e.g., null) when no input electrical signal is applied to tributary modulator 330. For example, referring to FIG. 4, controller 350 may control a bias point of I channel modulator 440, Q channel modulator 450, I channel modulator 460, and/or Q channel modulator 470….”) ; and input, at a moment other than the pre-set moment, a signal with correlation of 0 with the first input signal, or a 0 signal to the second electro-optical conversion unit ( Paragraphs [0042-0044] AND FIG. 6) .
One of ordinary skill in the art would have been motivated to combine the teaching of ZHANG et al. within the combined modified teaching of the Coherent optical receiver mentioned by Younce et al. and the Coherent Data Center Links mentioned by Jose Krause Perin et al. because the Minimizing polarization-dependent optical power for pm-m-qam transmitters mentioned by ZHANG et al. provides a method and system for implementation of multiple modulator and bias voltage calculation for controlling multiple power level of optical signals.
Therefore, it would have been obvious for one in the ordinary skills in the art before the effective filing date of the claimed invention to the Minimizing polarization-dependent optical power for pm-m-qam transmitters mentioned by ZHANG et al. within the combined modified teaching of the Coherent optical receiver mentioned by Younce et al. and the Coherent Data Center Links mentioned by Jose Krause Perin et al. for implementation of multiple modulator and bias voltage calculation for controlling multiple power level of optical signals.
It is noted that any citations to specific, pages, columns, lines, or figures in the prior art references and any interpretation of the reference should not be considered to be limiting in any way. A reference is relevant for all it contains and may be relied upon for all that it would have reasonably suggested to one having ordinary skill in the art. See MPEP 2123.
Allowable Subject Matter
3. Claims 4,5,6,7 and 8 are objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
4. The following is an examiner’s statement of reasons for objecting the claims as allowable subject matter:
As to claim 4, prior art of record does not teach or suggest the limitation mentioned within claim 4 : “…the second input signal is same as the first input signal; or the second input signal is a weighted sum of the first input signal at a plurality of different moments; or the second input signal is a symbol sequence of a weighted sum of the first input signal at a plurality of different moments; or the second input signal is a product of a symbol sequence of a weighted sum of the first input signal at a plurality of different moments and a random amplitude sequence.”
As to claim 5, prior art of record does not teach or suggest the limitation mentioned within claim 5 : “…the first electro-optical conversion unit is connected in parallel to the second electro-optical conversion unit, and the first electro-optical conversion unit is connected to a first input end of a low-speed coherent detection unit, and inputs the first output signal to the first input end, and the second electro-optical conversion unit is connected to a second input end of the low-speed coherent detection unit, and inputs the second output signal to the second input end; and the low-speed coherent detection unit is further configured to: perform a coherent detection operation on the first output signal and the second output signal to obtain the first output quantity and the second output quantity.”
As to claim 6, prior art of record does not teach or suggest the limitation mentioned within claim 6: “…the first electro-optical conversion unit is connected in series to the second electro-optical conversion unit, and a series structure of the first electro-optical conversion unit and the second electro-optical conversion unit is connected to a first input end of a low-speed coherent detection unit, and inputs a product of the first output signal and the second output signal to the first input end, and a second input end of the low-speed coherent detection unit is input a pre-set reference signal, and the low-speed coherent detection unit is further configured to: perform a coherent detection operation on the product of the first output signal and the second output signal as well as the pre-set reference signal to obtain the first output quantity and the second output quantity.”
As to claim 7, prior art of record does not teach or suggest the limitation mentioned within claim 7: “…the processor configured to: substitute the first output quantity and the second output quantity into a formula, to obtain the optical phase difference, as follows: φ = arg(I1 - jI2) where, I1 is the first output quantity, I2 is the second output quantity, φ is an optical phase difference of the output signal of the first electro-optical conversion unit and the output signal of the second electro-optical conversion unit, and arg(z) is principal argument angle of a complex number z.”
As to claim 8, prior art of record does not teach or suggest the limitation mentioned within claim 8 : “…multiply the second input signal with a low-frequency square wave before the second input signal is input to the second electro-optical conversion unit; and multiply the first output quantity and the second output quantity with the low-frequency square wave respectively, before the optical phase difference is determined based on the first output quantity and the second output quantity; and the processor is further configured to: input a product signal of the second input signal and the low-frequency square wave to the second electro-optical conversion unit; and determine the optical phase difference according to a product of the first output quantity and the low-frequency square wave and a product of the second output quantity and the low-frequency square wave.”
Any comments considered necessary by applicant must be submitted no later than the payment of the issue fee and, to avoid processing delays, should preferably accompany the issue fee. Such submissions should be clearly labeled “Comments on Statement of Reasons for Allowance.”
Examiner’s Notes
5. The Examiner acknowledges the following prior arts below as pertinent to the current applications claim limitations and inventive concept, although the following prior arts shown below were not relied upon to address the limitations within the claim , they are analogous art mentioning the inventive concept key points on (Optical transmitter, receiver , optical phase difference , elector optical conversion / MZM converter, modulation etc.).
1) Takahide Sakamoto et al.,"Coherent Synthesis of Optical Multilevel Signals by Electrooptic Digital-to-Analog Conversion Using Multi parallel Modulator," 6th October 2010, IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS, VOL. 16, NO. 5, SEPTEMBER/OCTOBER 2010,Pages 1140-1147.X.Z Qiu et al.," High Performance Burst-Mode Upstream Transmission for Next Generation PONs," 12th February 2007, Conference, Pages 1-3.
2) Bernhard Schrenk, “Electro absorption-modulated laser as optical transmitter and receiver: status and opportunities," 6th October 2020,IET Optoelectron., 2020, Vol. 14 Iss. 6,Pages 374-383.
3) M.A. Jarajreh et al.,"Improving the chromatic dispersion tolerance in long-haul fibre links using the coherent optical orthogonal frequency division multiplexing," 29th January 2010, IET Microw. Antennas Propag., 2010, Vol. 4, Iss. 5,Pages 651-657.
4) Fernando P. Guiomar et al.,"Receiver-side Digital Signal Processing for 100-GE Coherent Optical Transmission Systems," 30th July 2012, 2012 17th European Conference on Networks and Optical Communications,Pages 1-5.
5) ZHUGE QUNBI et al. (EP 3796573)
6) Nazarathy (USPUB 20230412274)
7) Palmer et al. (USPUB 20230412274)
8) Lewen et al. (USPAT 10180588)
9) Liu et al. (USPUB 20180316541 )
10) KANTER (USPUB 20180219633 )
11) ABE (USPUB 20160285558 )
12) NOGUCHI, HIDEMI et al. (WO 2015136877)
13) ABE JUNICHI (JP 2014146915 )
14) Izumi (USPUB 20120237206 )
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Conclusion
6. The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. Refer to PTO-892, Notice of Reference Cited for a listing of analogous art.
7. Any inquiry concerning this communication or earlier communications from the examiner should be directed to OMAR S ISMAIL whose telephone number is (571)272-9799 and Fax # is (571)273-9799. The examiner can normally be reached on M-F 9:00am-6:00pm.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, David C. Payne can be reached on (571) 272-3024. The fax phone number for the organization where this application or proceeding is assigned is (571)273-8300.
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/OMAR S ISMAIL/
Primary Examiner, Art Unit 2635
Prosecution Insights