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 .
Status of Claims
This action is responsive to the amendment filed April 27, 2026. Claims 1-20 are pending and stand rejected. This action is NON-FINAL. Although it follows applicant's response, it enters a new ground of rejection over Ketchum that was not necessitated by applicant's amendment; the action is therefore made non-final.
Response to Arguments
35 U.S.C. 112. Applicant points to the specification’s ¶ 750 (Fig. 164) as describing MRC processing circuitry feeding a MIMO transmitter. That paragraph recites the result without describing how combining is performed before transmission, and the specification's own appendix distinguishes receiver-side MRC ("at receiver, MRC can be determined"; "maximum ratio combining (MRC) receiver matched filter") from transmit-side maximum ratio transmission. The rejections under 35 U.S.C. 112(a) and 112(b) are maintained.
U.S.C. 102. Applicant's arguments directed to Negus are moot, as the Negus
rejections are withdrawn and replaced by the rejections over Ketchum below. Ketchum
cures the limitation applicant argued was missing from Negus, namely a channel matrix
of an impulse response of a channel, by disclosing the channel response provided to the
transmitter as a matrix of time-domain samples.
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claim 1-20 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention.
The specification does not reasonably convey that the inventors possessed a MIMO transmitter that transmits data streams processed by maximum ratio combining. As-filed ¶750 (Fig. 164) names a block of "MRC processing circuitry 16404" whose output is "provided to a MIMO transmitter 16406," but gives no operative description of how maximum ratio combining is performed before transmission, stating only that the circuitry "processes the signals as discussed in the appendix." The appendix in turn describes maximum ratio combining as a receiver operation ("at receiver, MRC can be determined" ; "maximum ratio combining (MRC) receiver matched filter") and identifies the transmit-side scheme as maximum ratio transmission. Disclosure of a labeled functional block, without conveying how the recited transmit side combining is performed, does not show possession of the claimed invention. Ariad Pharms. v. Eli Lilly, 598 F.3d 1336 (Fed. Cir. 2010) (en banc).
Claims 1-20 rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the enablement requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to enable one skilled in the art to which it pertains, or with which it is most nearly connected, to make and/or use the invention. The examiner does not believe it is possible to perform maximum ratio combining (MRC) prior to transmission because MRC requires multiple received replicas of the same signal. At the transmitter, there are no received replicas to combine you only have the baseband data streams, not noisy channel outputs. Therefore, when the claims state, “transmitting the MRC processed plurality of data streams” they are either (1) misusing the term MRC, or (2) relabeling MRT/precoding as MRC. Either way, the claims exceed what the specification actually teaches. The factors of In re Wands, 858 F.2d 731 (Fed. Cir. 1988), MPEP 2164.01(a), are weighed below.
(1) Breadth of the claims. The claims broadly require a MIMO transmitter that transmits "the MRC processed plurality of data streams," encompassing any transmit side maximum ratio combining.
(2) Nature of the invention. A MIMO communications system whose operation depends on signal processing operations (MRC) that have a fixed, mathematically defined meaning in the art.
(3) State of the prior art. Maximum ratio combining is uniformly a receiver-side diversity combining technique; transmit-side weighting is performed by maximum ratio transmission (MRT) or precoding. The specification itself reflects this division, describing maximum ratio combining as a receiver matched filter and maximum ratio transmission as the transmit-side scheme (as-filed specification, appendix).
(4) Level of ordinary skill. High; practitioners typically hold advanced degrees in communications or signal processing and would recognize that combining requires received replicas.
(5) Level of predictability. Signal processing is generally predictable and deterministic. Performing MRC before any signal is received is not a matter of unpredictability but is undefined as the specification describes it.
(6) Amount of direction provided by the inventor. None directed to the point at issue. As-filed, ¶750 names MRC processing circuitry 16404 whose output is provided to a MIMO transmitter; no algorithm, equation, or operative description is given for performing maximum ratio combining on streams prior to transmission, and the appendix mathematics are directed to receiver-side MRC and transmit-side MRT.
(7) Existence of working examples. None. The specification contains no working example of performing maximum ratio combining before transmission.
(8) Quantity of experimentation needed. Undue. Lacking any guidance reconciling the receiver-side definition of MRC with transmit-side performance, a person of ordinary skill would be required to develop a new operation in order to practice the claim as written.
Weighing these factors, the specification would require undue experimentation to make and use the claimed invention. The above provides a reasonable basis to question enablement, and the burden shifts to applicant to establish that the claimed subject matter is enabled. In re Swartz, 232 F.3d 862 (Fed. Cir. 2000).
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claim 1-20 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as failing to set forth the subject matter which the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the applicant regards as the invention.
Where applicant acts as his or her own lexicographer to specifically define a term of a claim contrary to its ordinary meaning, the written description must clearly redefine the claim term and set forth the uncommon definition so as to put one reasonably skilled in the art on notice that the applicant intended to so redefine that claim term. Process Control Corp. v. HydReclaim Corp., 190 F.3d 1350, 1357, 52 USPQ2d 1029, 1033 (Fed. Cir. 1999).
The term “maximum ratio combining (MRC)” in claims 1-20 is used by the claim to mean “maximum ratio transmission (MRC),” while the accepted meaning is “maximum ratio transmission (MRT).” The term is indefinite because the specification does not clearly redefine the term. The specification as-filed in ¶750 refers to the appendix and states the MRC circuit “processes the signals as discussed in the appendix” and “improves signal-to-noise ratio,” and that the MRC-processed signal is then fed into a MIMO transmitter. However, the equations in the appendix do not teach how to perform maximum ratio combining at the transmitter. These equations are standard derivations of zero-forcing, MMSE and MRC receiver combiners. MRC is a receiver-side diversity combiner: the receiver estimates the channel, rotates the signal by the conjugate channel coefficients and weights them proportional to their magnitude so the signals add coherently.
Claim Rejections - 35 USC § 102
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
Claim(s) 1-8, 10-18, and 20 is/are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Ketchum et al., US 7,197,084 B2 (hereinafter “Ketchum”). The claims are applied as best understood in view of the indefiniteness identified above, with the recited transmit-side "maximum ratio combining" read on Ketchum's transmit-side maximal-ratio precoding of the channel eigenmodes.
Claims 1 and 11.
Ketchum discloses a communications system, comprising:
a maximum ratio combining (MRC) circuit for receiving a plurality of data streams and processing the plurality of input data streams using maximum ration combining to improve signal to noise ratio (KETCHUM, FIG. 4, transmitter unit 400, which precodes the data streams on the channel eigenmodes to maximize the signal-to-noise ratio per spatial subchannel; "Singular value decomposition may thus be used to decompose the MIMO channel into its eigenmodes, with each eigenmode corresponding to a spatial subchannel" (C3:L24-30).); and
a MIMO transmitter for transmitting the MRC processed plurality of data streams over a plurality of separate communications links from the MIMO transmitter (KETCHUM C1:L20-35, the MIMO channel "may be decomposed into NS independent channels," each "a spatial
subchannel"), each of the plurality of separate communications links from one transmitting antenna of a plurality of transmitting antennas to each of a plurality of receiving antennas at a MIMO receiver (KETCHUM: "A MIMO system employs multiple (NT) transmit antennas and multiple (NR) receive antennas for data transmission" (C1:L10-15); the conditioned signals are "transmitted from NT transmit antennas over a MIMO channel 130 to a receiver 150" (C4:L9-10)), wherein the MIMO transmitter transmits the MRC processed plurality of data streams using a channel matrix of an impulse response of a channel (KETCHUM C11:L30-40: "The MIMO channel response estimates are provided to transmitter unit 400 as a sequence of NR x NT matrices of time-domain samples," i.e., a channel impulse response matrix at the transmitter; fast Fourier transformer 422 "receives the estimated channel impulse response matrix" (C13:L5-10).), the channel matrix created using a pilot signal transmitted on a pilot channel (KETCHUM: " The coded data may then be multiplexed with pilot data using, for example, time division multiplexing (TDM) or code division multiplexing (CDM). The pilot data is typically a known data pattern processed in a known manner, and may be used ... to estimate the response of the MIMO channel" (C8:L55-65). Under BRI the CDM pilot is a pilot transmitted on a pilot channel.). Claim 11 recites the same limitations as claim 1 in method form and 1 is anticipated for the same reasons
Claims 2 and 12.
Ketchum discloses the communications system of Claim 1 further including: a MIMO receiver for receiving the MRC processed plurality of data streams over the plurality of separate communications links from the MIMO transmitter (KETCHUM C4:L10-35, receiver 150 receives the transmitted streams over the MIMO channel); and second maximum ratio combining (MRC) circuit for processing the MRC processed plurality of data streams to remove the MRC processing and outputting the plurality of data streams (KETCHUM C4:L15-55: "A decision feedback equalizer 170, which includes a feed-forward filter 172 and a feedback filter 174," recovers and outputs the symbol streams, removing the transmit-side precoding; KETCHUM C5:L40-50, "A matched filter" performs the receive-side combining the specification equates to MRC).
Claim 3 and 13.
Ketchum discloses the communications system of Claim 1, wherein the MIMO transmitter transmits the carrier signal over at least one of an optical link or a radio frequency (RF) link (KETCHUM C4:L5-15, "transmitted from NT transmit antennas over a MIMO channel 130 to a receiver 150"; Ketchum transmits over a wireless MIMO channel via the transmit antennas,
meeting the recited radio frequency (RF) link).
Claims 4 and 14.
Ketchum discloses the communications system of Claim 1, wherein each of the plurality of separate communications links comprises independent parallel channels (KETCHUM C1:L20-35, same reasons as the independent claims).
Claims 5 and 15.
Ketchum discloses the communications system of Claim 1, wherein the channel matrix comprises a set of simultaneous equations, each equation representing a received signal which is a composite of a unique set of channel coefficients applied to the transmitted MRC processed plurality of data streams (KETCHUM C2:L50-60, "a channel response matrix, H, that describes the response" of the MIMO channel, the received symbol vector being the product of this matrix and the transmitted vector so that each received signal is a composite of the channel coefficients applied to the transmitted streams; KETCHUM C3:L1-10, "H(k) is the channel response matrix for frequency fk," whose entries supply the unique set of channel coefficients).
Claims 6 and 16.
Ketchum discloses the communications system of Claim 1, wherein the channel matrix can be decomposed using singular value decomposition (KETCHUM C13:L20-30, singular value decomposition block 424; C3:L1-30, singular value decomposition of the channel response matrix, taught with claim 1).
Claim 7 and 17.
Ketchum discloses the communications system of Claim 1, wherein the MIMO transmitter uses a water filling algorithm to determine power distribution for each of the plurality of separate communications links (KETCHUM C12:L50-C14:L15 : "water-filling analysis block 426" implements the "water-filling transmit energy distribution" to allocate power across the
eigenmodes).
Claims 8 and 18.
Ketchum discloses the communications system of Claim 1, wherein the MIMO transmitter implements minimum mean square error (MMSE) techniques for transmissions on the plurality of separate communications links (KETCHUM C12:L10-25, the transmit and receive filters are determined "based on a minimum mean square error (MMSE) criterion").
Claim 10.
Ketchum discloses the communications system of Claim 1, wherein the MIMO transmitter further comprises an antenna array for transmitting the plurality of separate communications links (KETCHUM C1:L15-25, transmit antenna array of multiple NT transmit antennas, taught with claim 1) and further wherein the mode division multiplexing circuitry, MRC circuit and MIMO transmitter configure the plurality of separate communications links to provide array gain (KETCHUM C12:L45-C13:L15, the water-filling distribution concentrates transmit power on the dominant eigenmodes, providing array gain across the transmit antenna array).
Claim 20.
Ketchum discloses a method, comprising: receiving a plurality of input data streams at mode division multiplexing circuitry (KETCHUM C3:L25-35, channel eigenmode decomposition resolves the MIMO channel into its eigenmodes, “with each eigenmode corresponding to a spatial subchannel” under the BRI the eigenmode decomposition circuitry that receives the data streams to be transmitted is the recited mode division multiplexing circuitry); and generating a first group of the plurality of input data streams having a first group of orthogonal functions applied thereto and a second group of the plurality of input data streams having a second group of orthogonal functions applied thereto onto a mode division multiplexed carrier signal (KETCHUM C10:L40-65 “a separate coding scheme may be used for each group of one
or more data streams” and “a separate modulation scheme may be used for each data stream or each group of one or more data streams,” disclosing the first and second groups of input data streams; KETCHUM C3:L5-55, the orthogonal functions applies to each group are the orthonormal columns of the unitary matrix V(k), which “may be used at the transmitter to precondition symbols prior to transmission” and thereby “orthogonalize the multiple symbol streams,” each group being preconditioned by its corresponding orthonormal columns into the eigenmode-multiplexed signal, which is the recited mode division multiplexed carrier signal under the broadest reasonable interpretation). The remaining limitations of claim 20 are met for the reasons given for claims 1 and 11.
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 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.
Claims 9 and 19 is/are rejected under 35 U.S.C. 103 as being unpatentable over Negus in view of Fitch (US 2011/0014885 A1 – hereinafter “Fitch”).
Claims 9 and 19.
Ketchum discloses the system and method of claims 1 and 11 but does not disclose “Almouti-type techniques.”
However, Fitch in the same field of endeavor teaches Almouti-type techniques (Paragraph [0004] discloses “In open-loop MIMO the transmitter typically transmits equal energy from each antenna element and applies symbol coding that is resilient to any channel conditions. An example of such coding is the Alamouti coding specified by the WiMAX forum”).
Therefore, it would have been obvious to one of ordinary skill in the art to combine Negus and Fitch before the effective filing date of the claimed invention. The motivation for this combination of references would have been to include Fitch’s Alamouti coding as a robust transmit diversity technique to maintain reliable communication during open-loop operation modes when precise channel state information is unavailable.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Ross Varndell whose telephone number is (571)270-1922. The examiner can normally be reached M-F, 9-5 EST.
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 http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, O’Neal Mistry can be reached at (313)446-4912. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of an application may be obtained from the Patent Application Information Retrieval (PAIR) system. Status information for published applications may be obtained from either Private PAIR or Public PAIR. Status information for unpublished applications is available through Private PAIR only. For more information about the PAIR system, see https://ppair-my.uspto.gov/pair/PrivatePair. Should you have questions on access to the Private PAIR system, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative or access to the automated information system, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/Ross Varndell/Primary Examiner, Art Unit 2674
Prosecution Insights