DETAILED ACTION
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 .
Claim Objections
Claims 1, 9, and 19 are objected to because of the following informalities: each have been amended to recite “the input first signals” and “ the input second signals” but then later on refers to them as “the first signals” and “the second signals” without “input”. While this does not rise to a clarity issue, the modifiers should be consistent with claim recitations.
Appropriate correction is required.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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.
Claim(s) 1, 8, 9, and 13 is/are rejected under 35 U.S.C. 103 as being unpatentable over Kobayashi et al, WO 2020/175014 A1 (citations will be given to U.S. Publication No. 2022/0149974 which is an official translation) in view of Zhou et al, U.S. Publication No. 2016/0142149 and Wu et al, U.S. Patent No. 7,606,498.
Regarding claim 9, Kobayashi teaches a receiver (see Kobayashi Figure 1, receiver 50) comprising:
a detector (see Figure 1, optical front end 520) configured to coherently receive (see paragraph [0022]) a polarization-multiplexed optical signal transmitted from a transmitter via a transmission line (see Figure 1, output from transmitter 10 to path 30 and paragraph [0030]); and
a digital signal processing circuit (see Figure 1, unit 530 and paragraph [0029]) configured to perform equalization signal processing on the reception signal coherently received (see Figure 1, adaptive equalization unit 534),, wherein the digital signal processing circuit includes:
a chromatic dispersion compensation filter (see Figure 1, wavelength dispersion compensation unit 533) configured to multiply each of a real component and an imaginary component of each of a first polarization and a second polarization of the reception signal by a filter coefficient that compensates for chromatic dispersion (see Figure 2, which shows details of unit 533 of Figure 1, inputs XI, XQ, YI, YQ to Hr and Hcd units and paragraph [0050]);
an adaptive equalizer (see Figure 1, adaptive equalization unit 534) configured to receive input of first signals indicating the real component and the imaginary component of the first polarization output from the chromatic dispersion compensation filter and second signals indicating the real component and the imaginary component of the second polarization output from the chromatic dispersion compensation filter (see Figure 2, “complex signals” XI, XQ, YI, YQ), to multiply each of the input first signals and the input second signals, third signals indicating phase conjugates of the real component and the imaginary component of the first polarization, and fourth signals indicating phase conjugates of the real component and the imaginary component of the second polarization by a complex impulse response (see Figure 2, “complex signals” and outputs from “conj” blocks to respective “h” blocks and paragraphs [0050]-[0051]), to add the first and the second signals each multiplied by the complex impulse response (see Figure 2, first and third addition units for each polarization of just the non-conjugated signals), to subject the added first and the second signals to phase rotation for carrier phase compensation for compensating for a frequency offset for each polarization (see Figure 2, output of first addition unit to first multiplier and third addition unit to the third multiplier and paragraph [0052]), to add the third and the fourth signals each multiplied by the complex impulse response (see Figure 2, second and fourth addition units for each polarization of conjugated signals), to subject the added third and fourth signals to rotation reverse to the phase rotation for the carrier phase compensation for each polarization (see Figure 2, outputs of the second addition unit to the second multiplier and of the fourth addition unit to the fourth multiplier and paragraph [0052]), to add, for each polarization, the signals subjected to the phase rotation for the carrier phase compensation and the signals subjected to the rotation reverse to the phase rotation for the carrier phase compensation, and to output the added signals;
(see Figure 2, outputs from first two multipliers to addition unit which produces Xrsig and outputs from bottom two multipliers to addition unit which outputs Yrisg), and
at least one memory storing instructions; and at least one processor configured to execute the instructions to (see claim 5) update the phase rotation for the carrier phase compensation and the complex impulse response that is multiplied by the adaptive equalizer (see paragraph [0054]).
Kobayashi does not expressively teach wherein
the carrier phase compensation [is] for compensating for a phase noise of a carrier; and
the updates are made by use of an output of the adaptive equalizer.
However, Zhou in a similar invention in the same field of endeavor teaches a receiver (see Zhou Figure 2b and paragraph [0010]) comprising an adaptive equalizer (see Figure 3, which is an embodiment of the digital signal processor of Figure 2b per paragraph [0011], adaptive equalizer 330) configured for updates to various coefficients (see paragraph [0025]) as taught in Zhou wherein
the updates are made by use of an output of the adaptive equalizer (see Figure 3, feedback from outputs of adaptive equalizer 330 to processes 392, 394 and paragraph [0025]).
One of ordinary skill in the art before the effective filing date of the invention would have found it obvious as a matter of simple substitution to replace the method of updating values taught in Kobayashi with the method of using output from an adaptive equalizer as taught in Zhou, to yield the predictable results of accurately determining updated values for compensation.
Kobayashi in view of Zhou does not expressively teach wherein the carrier phase compensation [is] for compensating for a phase noise of a carrier.
However, Wu in a similar invention in the same field of endeavor teaches an optical receiver (see Wu Figure 2) comprising a processor configured to perform carrier phase compensation (see Figure 2, carrier recovery 36 and Figure 5, “recovery block 36 (see FIG. 2), which performs carrier recovery and phase error correction, and symbol determination. FIG. 5 schematically illustrates a representative carrier recovery block 36 which performs these operations”) via a phase rotation (see Figure 5, which is an embodiment of carrier recovery 36, phase rotation 44) to compensate for a frequency offset (see column 7, “The phase rotator 44 uses the symbol phase error .DELTA..phi.(n+1) to compute the frequency offset parameter .psi.(n), and finally the total carrier phase error .kappa.(n+1). The frequency offset parameter .psi.(n), which is proportional to the frequency difference .DELTA.f between the Tx and LO frequencies, may conveniently be computed by accumulating successive symbol phase error values”) as taught in Kobayashi in view of Zhou wherein
the carrier phase compensation [is] for compensating for a phase noise of a carrier (see column 5, “The symbol estimates X'(n) and Y'(n) are 10-bit digital values, comprising 5-bits for each of the real and imaginary parts. These estimated symbol values include phase error due to the frequency offset between the Tx and LO frequencies, laser line width and phase noise” and column 6, “As will be appreciated, the first order term will vary from symbol-to-symbol, and therefore reflects the effects of phase noise of the Tx and LO lasers. As will be described in greater detail below, the second order term integrates phase differences over time, and thus is a comparatively slow-varying value which follows laser frequency excursions but is otherwise insensitive to phase noise. The scaling factors .mu..sub.1 and .mu..sub.2 may be programmable, and define the respective phase adjustment step size for each term”).
One of ordinary skill in the art before the effective filing date of the invention would have found it obvious to combine the teaching of correcting for both frequency offset and phase noise of a carrier via a phase rotation as taught in Wu with the system taught in Kobayashi in view of Zhou, the motivation being to improve the signal to noise ratio in the system (see Wu column 7, “Adding the corresponding phase error .DELTA..phi..sub.Y(n)=Im{Y'(n)e.sup.-j.kappa.(n)Y*(n)} computed for the Y-polarization (at 52) yields a symbol phase error .DELTA..phi.(n+1) with an improved signal-to-noise ratio”).
Independent claims 1 and 19 recite similar limitations as claim 9, and are rejected under similar rationale.
Regarding claim 8, Kobayashi in view of Zhou teaches all the limitations of claim 1, and further teaches wherein the adaptive equalizer is configured to compensate for distortion produced in the transmitter (see Kobayashi paragraph [0063]), distortion produced in the receiver (see Kobayashi paragraph [0058]), polarization mode dispersion, frequency offset, or phase noise of a light source.
Regarding claim 13, Kobayashi in view of Zhou and Wu teaches communication system comprising:
a transmitter configured to transmit a polarization-multiplexed optical signal via a transmission line (see Kobayashi Figure 1, transmitter 10 sending signal over line 30 and paragraph [0035]);
the receiver according to claim 9 (see above).
Claim(s) 2, 3, 10, and 14 is/are rejected under 35 U.S.C. 103 as being unpatentable over Kobayashi et al, WO 2020/175014 A1 (citations will be given to U.S. Publication No. 2022/0149974 which is an official translation) in view of Zhou et al, U.S. Publication No. 2016/0142149; Wu et al, U.S. Patent No. 7,606,498; and Kobayashi et al, “35-Tb/s C-band Transmission over 800 km Employing 1-Tb/s PS-64QAM signals enhanced by Complex 8 × 2 MIMO Equalizer” (published in 2019 Optical Fiber Communications Conference and Exhibition (OFC), March 2019, hereafter referred to as Kobayashi 2).
Regarding claim 10, Kobayashi in view of Zhou and Wu teaches all the limitations of claim 9, and further teaches wherein the adaptive equalizer includes a complex widely linear (WL) MIMO filter (see Kobayashi Figure 2, and paragraph [0049] indicates the MIMO nature. WL is implied by paragraph [0039]).
Kobayashi in view of Zhou and Wu does not expressively teach wherein the complex MIMO filter is a complex 8x2 MIMO filter.
However, Kobayashi 2 in a similar invention in the same field of endeavor teaches an adaptive equalizer comprising a complex MIMO filter (see Kobayashi 2, Figure 2 and Abstract) configured to act on a real and imaginary component of a first and second polarization (see Figure 2, XI, XQ, YI, YQ inputs) and phase conjugates of a real and imaginary component of a first and second polarization (see Figure 2, “conj” and section 2, first paragraph) as taught in Kobayashi in view of Zhou and Wu wherein
the complex MIMO filter is a complex 8x2 MIMO filter (see caption for Figure 2).
One of ordinary skill in the art before the effective filing date of the invention would have found it obvious as a matter of simple substitution to replace the MIMO filter of Kobayashi in view of Zhou with that of Kobayashi 2 to yield the predictable results of successfully equalizing the polarizations.
Claim 2 recites similar limitations as claim 10, and is rejected under similar rationale.
Regarding claim 3, Kobayashi in view of Zhou, Wu and Kobayashi 2 teaches all the limitations of claim 2, and further teaches wherein the 8x2 WL MIMO filter is a WL filter (see Kobayashi paragraph [0039] as combined with Kobayashi 2, Figure 2) configured to receive input of a complex signal indicating the real component and a complex signal indicating the imaginary component of the first polarization, a complex signal indicating the real component and a complex signal indicating the imaginary component of the second polarization (see Kobayashi 2, Figure 2, XI, XQ, YI, YQ inputs), a complex signal indicating the phase conjugate of the real component and a complex signal indicating the phase conjugate of the imaginary component of the first polarization, and a complex signal indicating the phase conjugate of the real component and a complex signal indicating the phase conjugate of the imaginary component of the second polarization (see Kobayashi 2, Figure 2, “conj” for each signal), and to output a complex signal of the first polarization and a complex signal of the second polarization (see Kobayashi 2, Figure 2, X-pol and Y-pol outputs, wherein the operations performed in the equalizer implies complex outputs from complex inputs).
Regarding claim 14, Kobayashi in view of Zhou and Wu teaches all the limitations of claim 13, and further teaches wherein the adaptive equalizer includes a complex widely linear (WL) MIMO filter (see Kobayashi Figure 2, and paragraph [0049] indicates the MIMO nature. WL is implied by paragraph [0039]).
Kobayashi in view of Zhou and Wu does not expressively teach wherein the complex MIMO filter is a complex 8x2 MIMO filter.
However, Kobayashi 2 in a similar invention in the same field of endeavor teaches an adaptive equalizer comprising a complex MIMO filter as taught in Kobayashi in view of Zhou (see Figure 2 and Abstract) as taught in Kobayashi in view of Zhou and Wu wherein
the complex MIMO filter is a complex 8x2 MIMO filter (see caption for Figure 2).
One of ordinary skill in the art before the effective filing date of the invention would have found it obvious as a matter of simple substitution to replace the MIMO filter of Kobayashi in view of Zhou and Wu with that of Kobayashi 2 to yield the predictable results of successfully equalizing the polarizations.
Claim(s) 7 is/are rejected under 35 U.S.C. 103 as being unpatentable over Kobayashi et al, WO 2020/175014 A1 (citations will be given to U.S. Publication No. 2022/0149974 which is an official translation) in view of Zhou et al, U.S. Publication No. 2016/0142149; Wu et al, U.S. Patent No. 7,606,498; and Arikawa et al, “Transmitter and receiver impairment monitoring using adaptive multi-layer linear and widely linear filter coefficients controlled by stochastic gradient descent” (published at Optics Express, Vol. 29, Issue 8, pages 11548-11561, April 2021, provided by Applicant as an IDS submission on 04/01/2024).
Regarding claim 7, Kobayashi in view of Zhou and Wu teaches all the limitations of claim 1, but does not expressively teach wherein the at least one processor is further configured to execute the instructions to estimate at least one of distortion produced in the transmitter or distortion produced in the receiver, based on the complex impulse response in the adaptive equalizer.
However, Arikawa in a similar invention in the same field of endeavor teaches a system comprising a transmitter, receiver (see Arikawa section 2.2, first paragraph), and an adaptive equalizer (see Figure 2 and caption) using a complex impulse response (see section 2.2, second paragraph, “All the filters are assumed finite impulse response filters with half-symbol spaced”) as taught in Kobayashi in view of Zhou in view of Wu wherein the system is further configured to
estimate at least one of distortion produced in the transmitter or distortion produced in the receiver, based on the complex impulse response in the adaptive equalizer (see section 2.2, final paragraph).
One of ordinary skill in the art before the effective filing date of the invention would have found it obvious to combine the teaching of monitoring transmitter and receiver distortion based on complex impulse response in an adaptive equalizer as taught in Arikawa with the system taught in Kobayashi in view of Zhou and Wu, the motivation being to quickly know where a dramatic increase in distortion is occurring in the system thereby remedying it rapidly.
Allowable Subject Matter
Claims 4-6, 11, 12, and 15-18 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.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to CASEY L KRETZER whose telephone number is (571)272-5639. The examiner can normally be reached M-F 10:00-7:00 PM Pacific Time.
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/CASEY L KRETZER/Primary Examiner, Art Unit 2635
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