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 .
Response to Amendment/Arguments
With the reply filed 12/31/25, Applicant has amended claims 13 and 20. Claims 1-5, 9-17, 20, 23 and 24 are currently pending. Applicant’s arguments filed 12/31/25 have been fully considered but they are not persuasive. Regarding the rejection of claims 13, 20 and 24 under 35 U.S.C. § 102 (a)(1) as being anticipated by Wang et al. (“Wang '061”), Applicant states that “there is no disclosure regarding use in connection with determining a channel estimate and null space estimate of a radio propagation channel, as required by claim 13 and 20” (emphasis in Remarks). In response, as a matter of claim construction, it is respectfully noted that claim 13 is drawn to a “method being performed by a user equipment” and recites the method step of “transmitting uplink reference signals towards the network node and uplink data and the DMRS on the uplink data channel…thereby assisting the network node in determining a channel estimate and a null space estimate of the radio propagation channel.” Claim 20 is drawn to a UE and recites similar limitations. Accordingly, the method of claim 13 and apparatus of claim 20 are drawn to operations performed by/at a UE. The only requirement for the UE and method performed thereby related to the above recited claim limitation is that of transmitting uplink reference signals, uplink data and DMRS. How those signals are used by the network node do not limit the UE and method performed by the UE. Nonetheless, the limitation is addressed below in the proposed combination of Wang '061 with Wang '831.
Regarding the rejection of claims 1, 17 and 23 as being unpatentable over Wang '061 in view of Wang '831, Applicant argues that the proposed combination fails to disclose the recited claim limitations, and in particular “determining a channel estimate of the radio propagation channel, and a null space estimate of the radio propagation channel, from the received reference signals and the received DMRS” (emphasis in Remarks). The Examiner respectfully disagrees with Applicant’s position. Although Applicant argues that “[n]either Wang '061, Wang '831, nor any of the other cited Art discloses or suggests these specific method steps, performed by the network node, of independent claim 1” (Remarks, p. 13), it is noted that the test for obviousness is not that the claimed invention must be expressly suggested in any one or all of the references. Rather, the test is what the combined teachings of the references would have suggested to those of ordinary skill in the art. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981). In the proposed combination, Wang '061 teaches that reference signals/DMRS may be used for data channel estimation (¶ [0049]), and Wang '831 further teaches that a DMRS pilot is used to determine a channel matrix, which may be used to determine a null space matrix (see abstract). It is respectfully submitted that the claimed invention, including the recited method steps, would reasonably have been suggested to one skilled in the art based on the combined teachings of the references, as detailed in the rejection below, and the rejection of the claims is thus maintained.
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.
Claims 1, 13, 17, 20, 23 and 24 are rejected under 35 U.S.C. 103 as being unpatentable over Wang et al. U.S. Pat. App. Pub. No. 2020/0092061 (hereinafter “Wang '061”) in view of Wang et al. U.S Pat. App. Pub. No. 2015/0271831 (hereinafter “Wang '831”).
Regarding claims 1, 17 and 23, Wang '061 discloses a network node (base station 110) serving a user equipment (i.e. UE 120) over a radio propagation channel (see Fig. 1), the network node comprising a processor 810 (Fig. 8) and a computer readable storage medium (¶ [0020]) to implement a method of estimating the radio propagation channel (¶ [0049]), the method comprising: configuring the user equipment to use single port transmission for transmitting on an uplink data channel to the network node (¶ [0154]); transmitting downlink control information (DCI) towards the UE, wherein the downlink control information indicates which port the UE is to use for transmission of demodulation reference signals (DMRS) on the uplink data channel, as DCI is used to schedule uplink data transmission on a terminal side, and a single antenna port is a resource used for uplink DMRS (¶¶ [0051], [0070], [0154]); receiving uplink reference signals from the UE and uplink data and the DMRS on the uplink data channel from the UE (¶ [0051], [0070], [0154], [0198]); and determining a channel estimate of the radio propagation channel from the received uplink reference signals and the received DMRS (¶¶ [0049], [0380]). Wang '061 does not expressly show that a null space estimate is determined from the uplink reference signals and the received DMRS.
Wang '831 discloses that a null space estimate is determined based on received reference signals/DMRS (¶ [0041]). It would have been obvious to one of ordinary skill in the art, prior to the effective filing date of the claimed invention, to estimate a null space matrix from uplink DMRS/reference signals, as suggested by Wang '831, in the method of Wang '061, in order to help eliminate interference (see Wang '831, ¶ [0041]).
Regarding claims 13, 20 and 24, Wang '061 discloses a user equipment (i.e. UE 120) assisting a network node (i.e. base station 110) in estimating a radio propagation channel (see Fig. 1), the UE comprising a processor 810 (Fig. 8) and a computer readable storage medium (¶ [0020]) to implement a method comprising: receiving configuration information from the network node to use single port transmission for transmitting on an uplink data channel to the network node (¶ [0154]); receiving downlink control information (DCI) from the network node, wherein the downlink control information indicates which port the UE is to use for transmission of demodulation reference signals (DMRS) on the uplink data channel, as DCI is used to schedule uplink data transmission on a terminal side, and a single antenna port is a resource used for uplink DMRS (¶¶ [0051], [0070], [0154]); and transmitting uplink reference signals towards the network node and uplink data and the DMRS on the uplink data channel in accordance with the configuration (¶ [0051], [0070], [0154], [0198]), thereby assisting the network node in estimating the radio propagation channel (¶¶ [0049], [0380]). Although, as a matter of claim construction, the following limitation is not considered a requirement for the method of claim 13 or the UE of claim 24 since they describe functions performed at a network node, Wang '061 does not expressly show that a null space estimate is determined from the uplink reference signals and the received DMRS at the network node.
Wang '831 discloses that a null space estimate is determined based on received reference signals/DMRS by an uplink device (¶ [0041]). It would have been obvious to one of ordinary skill in the art, prior to the effective filing date of the claimed invention, to estimate a null space matrix from uplink DMRS/reference signals, as suggested by Wang '831, in the method of Wang '061, in order to help eliminate interference (see Wang '831, ¶ [0041]).
Claims 2, 11, 12 and 14-16 are rejected under 35 U.S.C. 103 as being unpatentable over Wang '061 in view of Wang '831, as applied above, and further in view of Shibaike et al. U.S. Pat. App. Pub. No. 2025/0015952.
Regarding claim 2, Wang '061 in combination with Wang '831 disclose a method for estimating a radio propagation channel by a network node, as described above, but do not expressly disclose verifying that the user equipment is configurable to selectively switch transmission on the uplink data channel between at least two ports.
Shibaike discloses that a UE may report capability information indicated a supported SRS transmission port switching pattern (¶ [0037]), which provides indication that the UE is configurable to selectively switch between transmission ports. It would have been obvious to one of ordinary skill in the art, prior to the effective filing date of the claimed invention, to provide information regarding SRS port switching capability, as suggested by Shibaike, in the method of Wang '061 and Wang '831 in order to a establish beam management procedure.
Regarding claim 11, Wang '061 in combination with Wang '831 disclose a method for estimating a radio propagation channel by a network node, as described above, but do not expressly disclose configuring the UE to use a first port for transmitting on the uplink data channel to the network node and configuring the UE to use a second port for a next-most in time occurring transmission on the uplink data channel to the network node.
Shibaike discloses that a UE may be configured to transmit on a plurality of ports, and configured by a higher layer parameter for a TDD UL/DL configuration for transmissions (¶ [0041]-[0042], [0056], [0070]). It would have been obvious to one of ordinary skill in the art, prior to the effective filing date of the claimed invention, to configure a UE to transmit using several ports, as suggested by Shibaike, in the method of Wang '061 and Wang '831 to provide antenna diversity.
Regarding claim 12, Wang '061 in combination with Wang '831 disclose a method for estimating a radio propagation channel by a network node, as described above, but do not expressly disclose configuring the UE to switch from one port to another port when transmitting uplink data from one transmission to a next transmission.
Shibaike discloses that a UE may be configured to switch transmission using a plurality of ports, and is configured by a higher layer parameter for a TDD UL/DL transmissions (¶ [0041]-[0042], [0056], [0070]). It would have been obvious to one of ordinary skill in the art, prior to the effective filing date of the claimed invention, for a UE to switch transmission ports, as suggested by Shibaike, in the method of Wang '061 and Wang '831 for antenna diversity.
Regarding claim 14, Wang '061 in combination with Wang '831 disclose a method for assisting a network node in estimating a radio propagation channel performed by a UE, as described above, but do not disclose verifying to the network node that the UE is configurable to selectively switch transmission on the uplink data channel between at least two ports.
Shibaike discloses that a UE may report capability information indicated a supported SRS transmission port switching pattern (¶ [0037]), which provides indication that the UE is configurable to selectively switch between transmission ports. It would have been obvious to one of ordinary skill in the art, prior to the effective filing date of the claimed invention, to provide information regarding SRS port switching capability, as suggested by Shibaike, in the method of Wang '061 and Wang '831 in order to a establish beam management procedure.
Regarding claim 15, Wang '061 in combination with Wang '831 disclose a method for estimating a radio propagation channel by a network node, as described above, but do not expressly disclose configuring the UE to use a first port for transmitting on the uplink data channel to the network node and configuring the UE to use a second port for a next-most in time occurring transmission on the uplink data channel to the network node.
Shibaike discloses that a UE may be configured to transmit on a plurality of ports, and configured by a higher layer parameter for a TDD UL/DL configuration for transmissions (¶ [0041]-[0042], [0056], [0070]). It would have been obvious to one of ordinary skill in the art, prior to the effective filing date of the claimed invention, to configure a UE to transmit using several ports, as suggested by Shibaike, in the method of Wang '061 and Wang '831 to provide antenna diversity.
Regarding claim 16, Wang '061 in combination with Wang '831 disclose a method for estimating a radio propagation channel by a network node, as described above, but do not expressly disclose configuring the UE to switch from one port to another port when transmitting uplink data from one transmission to a next transmission.
Shibaike discloses that a UE may be configured to switch transmission using a plurality of ports, and is configured by a higher layer parameter for a TDD UL/DL transmissions (¶ [0041]-[0042], [0056], [0070]). It would have been obvious to one of ordinary skill in the art, prior to the effective filing date of the claimed invention, for a UE to switch transmission ports, as suggested by Shibaike, in the method of Wang '061 and Wang '831 for antenna diversity.
Claims 3 and 5 are rejected under 35 U.S.C. 103 as being unpatentable over Wang '061 in view of Wang '831, as applied to claim 1 above, and further in view of Abdoli et al. U.S. Pat. App. Pub. No. 2023/0155864.
Regarding claim 3, Wang '061 in combination with Wang '831 disclose a method for estimating a radio propagation channel by a network node, as described above, but do not disclose that the null space estimate is determined as a function of a channel prediction.
Abdoli discloses a system employing a null-space dimension characterization where a predicted UL is based on SRS channel estimation (¶¶ [0418]-[0423]). It would have been obvious to one of ordinary skill in the art, prior to the effective filing date of the claimed invention, to provide channel prediction from channel estimation, as suggested by Shibaike, in the method of Wang '061 and Wang '831, as deriving a channel prediction from a channel estimate to provide channel information is a known technique for characterizing a channel.
Regarding claim 5, in the proposed combination, Abdoli further discloses that the channel prediction is determined as a function of a weight matrix H with weight values (i.e. coefficients) (see ¶¶ [0173], [0418]).
Claim 4 is rejected under 35 U.S.C. 103 as being unpatentable over Wang '061 in view of Wang '831 and Abdoli et al., as applied to claim 3 above, and further in view of Sahraei et al. U.S. Pat. App. Pub. No. 2021/0359731.
Regarding claim 4, Wang '061 in combination with Wang '831 and Abdoli disclose a method for estimating a radio propagation channel by a network node, as described above, but do not disclose that the null space estimate is determined as defined by the equation in claim 4.
Sahraei discloses an equation for estimating a null space as identified in the first term of the equation in paragraph [0107] (see ¶¶ [0097], [0109], where the null matrix K corresponds to: I – H+H). It would have been obvious to one of ordinary skill in the art, prior to the effective filing date of the claimed invention, to define the null space matrix as disclosed by Sahraei, in the method of Wang '061 et al., as it is a known way to define a null space matrix.
Claims 9 and 10 rejected under 35 U.S.C. 103 as being unpatentable over Wang '061 in view of Wang '831, as applied to claim 1 above, and further in view of Sahraei et al.
Regarding claim 9, Wang '061 in combination with Wang '831 disclose a method for estimating a radio propagation channel by a network node, as described above, but do not expressly disclose applying precoder weights to a downlink signal carrying the downlink data transmission towards the UE, applying amplitude clipping to the downlink signal, the downlink clipping yielding an in-band error signal, and transmitting the downlink signal, wherein the in-band error signal is projected into a null space given by the null space estimate.
Sahraei discloses transmitting a downlink signal by applying precoder weights (¶ [0085]) to downlink signals (see Figs. 3-4), applying amplitude clipping to the downlink signal, yielding an in-band error signal (¶ [0048]), and transmitting the downlink signal, where one skilled in the art would recognize that the in-band error signal would be projected into a null space along with other portions of the space. It would have been obvious to one of ordinary skill in the art, prior to the effective filing date of the claimed invention, to apply precoding and transmission of precoded signals, as suggested by Sahraei, in the method of Wang '061 and Wang '831, as precoding is a known way to provide efficient MIMO communications (see Sahraei, ¶ [0004]).
Regarding claim 10, in the proposed combination, Sahraei further discloses that the precoding weights are determined as a function of the channel state information received from the UE, the uplink reference signals, and/or the DMRS (¶ [0085]).
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 David B. Lugo whose telephone number is 571-272-3043. The examiner can normally be reached M-F, 9-6.
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/DAVID B LUGO/Primary Examiner, Art Unit 2631
4/4/2026