DETAILED ACTION
Response to Arguments
1. Applicant's arguments filed 5/27/2026 have been fully considered but they are not persuasive. Applicant states (see pages 5 and 6 of the Remarks) “The Golay codes of Du are not CLS sequence blocks, nor are they SCS sequence blocks (e.g., claim 3), as the Golay codes do not remain complementary under distortions (e.g., a channel frequency offset) that are consistent from symbol to symbol. This distinction is highlighted in previously submitted Exhibit C.
Page 3 of the Third Office Action asserts that Du does, in fact, teach orthogonality in the matrices at paragraphs 0173, 0177, 0223, and Figure 4C, and without guard intervals at paragraphs 0163 and 0202. Applicant respectfully traverses.
As noted in Exhibit C, Golay codes are not orthogonal. However, to the extent that the text of Du does use the word orthogonal, Applicant also notes that contrary to the assertion of the Third Office Action, there is still a prefix used between sequence blocks. That is, paragraph 0163 describes a "cyclic prefix and cyclic suffix [that] are both 0." A zero prefix is not the same as no prefix. This distinction is illustrated in paragraph 0202 and table 2, where a prefix of a "minus sign" is shown as a in column al of Table 2. In either event, there is still a prefix, and thus the blocks are transmitted with a guard interval. To the extent that paragraph 0202 also says "at a first moment, the CE may not have a cyclic prefix (that is may not have al in Table 1 or Table 2). Certainly if a plurality of moments (that is, two or more moments) are used to complete MIMO channel estimation, a cyclic prefix may exist from the second moment." Thus, it is clear that a prefix is present when there is a plurality of moments. Further, the passage makes no mention of the omission of a suffix, so even for a single moment, there is a suffix, which has been indicated to be a guard interval (see page 3 of the Third Office Action). Since Du always teaches at least a suffix/guard interval, Du does not anticipate claims 1 or 11.”
However, it is the understanding of the Examiner that Du discloses that the complementary low-sum cross-correlation (CLS) sequence block is a complementary Golay code sequence (see sections 0220-0221) with a zero (low) cross-correlation sum (as disclosed in sections 0220-0224). Furthermore, Du discloses the use of the complementary Golay code sequence in the presence of noise (see sections 0164-0166). Du further discloses the complementary Golay code sequence comprises columns of orthogonal CE sequences in a matrix as shown in Fig. 4C (see also sections 0173, 0177, and 0223). Du also discloses a complementary Golay code sequence Ui(n) “does not include a cyclic prefix or a cyclic suffix”. Therefore, based on the above disclosure, it is the understanding of the Examiner that Du discloses “a complementary low-sum cross correlation (CLS) sequence block comprising orthogonal columns and configured to be transmitted with guard intervals”.
Applicant further states (see page 6 of the Remarks) “To the extent that page 4 of the Office Action asserts that Thomas teaches CLS sequence blocks, Applicant traverses. That is, Thomas' paragraphs 0042-0046 and 0055-56 teach an orthogonal and quasi-orthogonal codes for synchronous channel sounding in an orthogonal frequency division multiplexing (OFDM) system that inherently limits sidelobes per tone (i.e., no self-interference). The OFDM system cannot be used in an impulse radio channel.”
However, it is the understanding of the Examiner that Thomas discloses that the complementary low-sum cross-correlation (CLS) sequence block is a CSI-RS/pilot signal sequence with a low-sum cross correlation (as disclosed in section 0055), wherein the sequence is complementary based on the good cross-correlation properties as disclosed in section 0056. Therefore, based on the above disclosure, it is the understanding of the Examiner that Thomas discloses “a complementary low-sum cross-correlation (CLS) sequence”.
Claim Rejections - 35 USC § 102
2. 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)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
3. Claims 1-4, 11, 14-16, and 23 are rejected under 35 U.S.C. 102(a)(2) as being anticipated by Du et al. (previously cited in Office Action 9/9/2025).
Regarding claim 1, Du et al. a source (see Fig. 13) comprising:
an antenna (see section 0340);
a transceiver (Fig. 13, block 1310) coupled to the antenna; and
a control circuit (Fig. 13, block 1320) coupled to the transceiver and configured to:
cause the transceiver to send (as disclosed in sections 0219-0229) a complementary low-sum cross-correlation (CLS) sequence block (M sequences in the PPDU) to a remote device (Fig. 12) for ranging (distance calculation as disclosed in sections 0154-0155 and 0170), wherein the CLS block comprises orthogonal columns (the CLS block comprising columns of orthogonal CE sequences as disclosed in sections 0173, 0177, and 0223, see also Fig. 4C.) and is configured without guard intervals (wherein the CE sequences can be configured without a cyclic prefix/suffix (guard interval) as disclosed in sections 0163 and 0202).
Regarding claim 2, Du et al. discloses the CLS sequence block comprises a complementary zero-sum cross-correlation (CZC) sequence block (as disclosed in section 0152).
Regarding claim 3, Du et al. discloses the CLS sequence block comprises a supercomplementary set (SCS) sequence block (as disclosed in sections 0180-0183, wherein N=256 for a supercomplementary sequence block as disclosed in sections 0180-0183).
Regarding claim 4, Du et al. discloses the CLS sequence block comprises a supercomplementary zero-sum cross-correlation (SZC) sequence block (as disclosed in sections 0180-0183, wherein N=256).
Regarding claim 11, Du et al. discloses a mobile device (see Figs. 2 and 12, which both illustrate a mobile device) comprising:
an antenna (see Fig. 2, STA, section 0144);
a receiver (Fig. 12, block 1202) coupled to the antenna, the receiver comprising a correlator (as disclosed in sections 0266); and
a control circuit (Fig. 12, block 1201) coupled to the receiver and configured to: cause the correlator to correlate a received signal with a complementary low-sum cross-correlation (CLS) sequence block to derive a channel estimate (as disclosed in sections 0162-0170), wherein the CLS block comprises orthogonal columns (the CLS block comprising columns of orthogonal CE sequences as disclosed in sections 0173, 0177, and 0223, see also Fig. 4C.) and is configured without guard intervals (wherein the CE sequences can be configured without a cyclic prefix/suffix (guard interval) as disclosed in sections 0163 and 0202).
Regarding claim 14, Du et al. discloses the CLS sequence block comprises a complementary zero-sum cross-correlation (CZC) sequence block (as disclosed in section 0152).
Regarding claim 15, Du et al. discloses the CLS sequence block comprises a supercomplementary set (SCS) sequence block (as disclosed in sections 0180-0183, wherein N=256 for a supercomplementary sequence block as disclosed in sections 0180-0183).
Regarding claim 16, Du et al. discloses the CLS sequence block comprises a supercomplementary zero-sum cross-correlation (SZC) sequence block (as disclosed in sections 0180-0183, wherein N=256).
Regarding claim 23, Du et al. discloses the SCS sequence block comprises an even number of CLS sequence blocks per symbol (see Fig. 4c, section 0161) to keep zero sidelobes (as disclosed in section 0156, see also section 0197) under consistent distortions caused by a channel frequency offset.
Claim Rejections - 35 USC § 103
4. 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.
5. Claims 5-8, 13, 17, and 18 are rejected under 35 U.S.C. 103 as being unpatentable over Du et al. (previously cited in Office Action 9/9/2025) in view of Thomas et al. (previously cited in Office Action 9/9/2025).
Regarding claims 5-8, Du et al. does not specifically disclose a memory associated with the control circuit, the memory configured to store the CLS sequence block., wherein the control circuit is configured to retrieve the CLS sequence block from the memory. Du et al. further does not disclose the control circuit is further configured to receive a channel estimation from the remote device through the antenna and transceiver responsive to having sent the CLS sequence block.
However, Thomas et al. also discloses sending a complementary low-sum cross-correlation (CLS) sequence block (CSI-RS/pilot signals as disclosed in sections 0042-0046, 0055-0056) to a remote device (see Fig. 1, blocks 102/103). Thomas et al. further discloses a memory (see Fig. 13, block 1304) associated with a control circuit (Fig. 13, block 1302), the memory configured to store the CLS sequence block (as disclosed in section 0031), wherein the control circuit is configured to retrieve the CLS sequence block from the memory (as disclosed in section 0035, wherein the signal processing unit retrieves instructions and programs from the memory). Thomas et al. also discloses the control circuit is further configured to receive a channel estimation (CSI feedback as disclosed in section 0077, which includes a channel estimate such as channel quality mean/variance as disclosed in section 0033) from the remote device (UE) through an antenna and transceiver (see Fig. 12, blocks 1206 and 1208) responsive to having sent the CLS sequence block (as disclosed in sections 0076-0077). Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the present invention to modify the method/apparatus of Du et al. with the signal processing and channel estimation feedback as taught by Thomas et al. since Thomas et al. discloses the channel estimation feedback is necessary in order to predistort and beamform signals for transmission (see section 0033) using a spreading technique which gives a gain above noise and interference (see section 0025).
Regarding claims 13, 17, and 18, Du et al. discloses the mobile device comprises a memory for storing the CLS sequence block (as disclosed in section 0193); however, Du et al. does not specifically disclose the control circuit is configured to retrieve the CLS sequence block from the memory. Du et al. also does not specifically disclose the control circuit is further configured to send information to a source, wherein the information is derived from the channel estimate or wherein the information comprises the channel estimate.
However, Thomas et al. also discloses a mobile device (see Fig. 12) comprising a memory for storing the CLS sequence block (see block 1204, see section 0031), wherein a control circuit (Fig. 12, block 1202) is configured to retrieve the CLS sequence block from the memory (as disclosed in section 0035, wherein the signal processing unit retrieves instructions and programs from the memory). Thomas et al. further discloses the control circuit is further configured to send information (as disclosed in sections 0033 and 0076-0077) to a source (BS), wherein the information (CSI feedback as disclosed in section 0077) is derived from the channel estimate or wherein the information comprises the channel estimate (channel quality mean/variance estimation as disclosed in section 0033). Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the present invention to modify the method/apparatus of Du et al. with the signal processing and channel estimation feedback as taught by Thomas et al. since Thomas et al. discloses the channel estimation feedback is necessary in order to predistort and beamform signals for transmission (see section 0033) using a spreading technique which gives a gain above noise and interference (see section 0025).
6. Claims 12 is rejected under 35 U.S.C. 103 as being unpatentable over Du et al. (previously cited in Office Action 9/9/2025) in view of Hewavithana et al. (previously cited in Office Action 9/9/2025).
Regarding claim 12, Du et al. does not specifically disclose the control circuit is configured to remove a carrier frequency offset from a correlated signal from the correlator.
However, Hewavithana et al. further discloses removing a carrier frequency offset from channel estimates (see Fig. 4, see section 0048) which include a correlation matrix as disclosed in sections 0081 and 0086. Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the present invention to modify the method/apparatus of Du et al. with the removal of carrier frequency offset from correlations/channel estimates as disclosed by Hewavithana et al. since Hewavithana et al. discloses removal of carrier frequency offset mitigates ICI and phase error (see section 0034).
7. Claims 21 is rejected under 35 U.S.C. 103 as being unpatentable over Du et al. (previously cited in Office Action 9/9/2025) in view of Kim et al. (previously cited in Office Action 9/9/2025).
Regarding claim 21, Du et al. discloses a method of determining distance (distance calculation as disclosed in sections 0154-0155 and 0170) comprising: transmitting a complementary low-sum cross-correlation (CLS) sequence block from a source to a remote device (as disclosed in sections 0219-0229), wherein the CLS block comprises orthogonal columns (the CLS block comprising columns of orthogonal CE sequences as disclosed in sections 0173, 0177, and 0223, see also Fig. 4C.) and is configured without guard intervals (wherein the CE sequences can be configured without a cyclic prefix/suffix (guard interval) as disclosed in sections 0163 and 0202). Du et al. does not specifically disclose receiving from the source, a channel estimate.
However, Kim et al. discloses (see sections 0165-0167) a source (base station) and a remote device (UE) for receiving, from the source (base station), a channel estimate (uplink channel estimation). Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the present invention to modify the method/apparatus of Du et al. with the feedback of the uplink channel estimation as disclosed by Kim et al. since Kim et al. states the estimation can be used to reduce channel overhead feedback (see section 0172).
8. Claims 9, 10, and 19 are rejected under 35 U.S.C. 103 as being unpatentable over Du et al. (previously cited in Office Action 9/9/2025) in view of Thomas et al. (previously cited in Office Action 9/9/2025), and in further view of Li et al. (previously cited in Office Action 9/9/2025).
Regarding claims 9, 10, and 19, Du et al. and Thomas et al. do not specifically disclose the information received at the source comprises a time of arrival (TOA) or a distance between the source and the remote device. However, Li et al. discloses a system which determines a distance estimation and TOA estimation (as disclosed in section 0156) at a remote device (second device), wherein these estimations are transmitted back to a source (first device). Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the present invention to modify the method/apparatus of Du et al. and Thomas et al. with the distance estimation feedback as taught by Li et al. since Li et al. discloses the distance (ranging) estimation feedback supports compensation of clock offset (see section 0157).
9. Claims 22 is rejected under 35 U.S.C. 103 as being unpatentable over Du et al. (previously cited in Office Action 9/9/2025), in view of Thomas et al. (previously cited in Office Action 9/9/2025), and in further view of Hewavithana et al. (previously cited in Office Action 9/9/2025).
Regarding claim 22, Du et al. discloses a method of determining distance, comprising: at a mobile terminal (see Figs. 2 and 12, which both illustrate a mobile device), receiving, from a source a signal with a complementary low-sum crosscorrelation (CLS) sequence block (see sections 0219-0236, M sequences), wherein the CLS block comprises orthogonal columns (the CLS block comprising columns of orthogonal CE sequences as disclosed in sections 0173, 0177, and 0223, see also Fig. 4C.) and is configured without guard intervals (wherein the CE sequences can be configured without a cyclic prefix/suffix (guard interval) as disclosed in sections 0163 and 0202); and
using a correlator (see section 0165, see also section 0266) at the mobile terminal to correlate a received version of the CLS sequence block with a known CLS sequence block to derive a channel estimate (as disclosed in sections 0162-0170). Du et al. does not specifically disclose removing a carrier frequency offset from the channel estimate and sending information derived from the channel estimate from the mobile terminal to the source.
However, Thomas et al. also discloses a mobile device (see Fig. 12) comprising a control circuit further configured to send information (as disclosed in sections 0033 and 0076-0077) to a source (BS), wherein the information (CSI feedback as disclosed in section 0077) is derived from the channel estimate (as disclosed in sections 0033 and 0077). Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the present invention to modify the method/apparatus of Du et al. with the CSI feedback as taught by Thomas et al. since Thomas et al. discloses the channel estimation feedback is necessary in order to predistort and beamform signals for transmission (see section 0033) using a spreading technique which gives a gain above noise and interference (see section 0025).
Hewavithana et al. further discloses removing a carrier frequency offset from channel estimates (see Fig. 4, see section 0048). Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the present invention to modify the method/apparatus of Du et al. and Thomas et al. with the removal of carrier frequency offset from channel estimates as disclosed by Hewavithana et al. since Hewavithana et al. discloses removal of carrier frequency offset mitigates ICI and phase error (see section 0034).
Conclusion
10. THIS ACTION IS MADE FINAL. 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.
11. Any inquiry concerning this communication or earlier communications from the examiner should be directed to CURTIS B ODOM whose telephone number is (571)272-3046. The examiner can normally be reached 8-5.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Hannah S Wang can be reached at (571)-272-9018. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/CURTIS B ODOM/Primary Examiner, Art Unit 2631 July 29, 2026
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