DETAILED ACTION
Specification
The disclosure is objected to because of the following informalities:
In paragraphs 0012, 0039, 0059, and 0066, the reference to “PCT Published Application WO 2021/136480” should be corrected to “PCT Published Application WO 2021/163480”.
Appropriate correction is required.
Claim Objections
Claims 6, 8, 10, and 12 are objected to because of the following informalities:
In line 3 of claim 6, the phrase “follows the Wi-Fi standard can be decoded by another WiFi-device” should be changed to something such as “follows the Wi-Fi standard and can be decoded by another WiFi-device”.
In lines 2-3 of claim 8, the phrase “baseband signal filtering” should be amended to improve the wording. For example, it could be changed to “baseband signal filter” or “baseband signal filtering circuitry”.
In lines 3-4 of claim 10, “the analog to digital converter the packet length counter” should be changed to “the analog to digital converter, the packet length counter”.
In line 3 of claim 12, “the a second of two pre-specified WiFi compatible packets” should be change to “the second of two pre-specified WiFi compatible packets”.
Appropriate correction is required.
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.
Claims 1-10, 12-15, and 17 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Wang* et al (“28μW IoT Tag That Can Communicate with Commodity WiFi Transceivers via a Single-Side-Band QPSK Backscatter Communication Technique”).
* Cited in Applicant’s IDS filed 1/26/2024.
Regarding claim 1: Wang discloses a method for waking a transceiver for communicating directly with commodity Wi-Fi transceivers (TRXs) via backscatter modulation in an integrated tag device, comprising:
sensing an incident Wi-Fi-compliant wake-up signal with a wake-up stage (disclosed throughout; see the second and third paragraphs of column 1 on page 312 and Figure 20.1.2, for example, which indicate that the backscatter-based IoT tag includes a “wake-up receiver” (WuRX) that senses “low-power communication with commodity WiFi hardware”; this includes “two pre-specified-length packets” that are detected on the WuRX; for example, the third paragraph in column 1 on page 312 indicates that “two pre-specified-length packets at a pre-specified separation” are “energy-detected by the on-chip WuRX in a backchannel communication-like approach”);
upon wake-up, sensing a payload packet with a sync stage (disclosed throughout; see the fourth paragraph of column 1 on page 312, which indicates that “After wake-up and synchronization, the tag counts for a pre-specified amount of time until the payload of the incident WiFi signal begins to be received at the tag’s antenna”; thus the tag device has a processing stage (sync stage) that senses when the payload of the incident WiFi signal begins), the sync stage having higher bandwidth and power than the wake-up stage (the processing stage (sync stage) that senses the start of the payload is part of what Wang describes as the “backscatter circuits”; as indicated in the second paragraph of column 2 on page 312, the back scatter circuits consume 28 µW of power, while the wakeup circuits consume 2.8 µW), the sync stage enabling a backscatter transmission circuit in sync with the payload (disclosed throughout; for example, see the second paragraph of column 1 on page 312, which indicates that after waiting for the header to pass, the IoT “backscatters during the payload”).
Regarding claim 7: Wang discloses a wake-up transceiver in an integrated tag device for communicating directly with commodity Wi-Fi transceivers (TRXs) via backscatter modulation comprising:
a wake-up receiver having an energy-detection based architecture and having circuitry to conduct a counter-based wake up responsive to two pre-specified WiFi compatible packets (disclosed throughout; see the second and third paragraphs of column 1 on page 312 and Figure 20.1.2, for example, which indicate that the backscatter-based IoT tag includes a “wake-up receiver” (WuRX) that senses “low-power communication with commodity WiFi hardware”; this includes “two pre-specified-length packets” that are detected on the WuRX; for example, the third paragraph in column 1 on page 312 indicates that “two pre-specified-length packets at a pre-specified separation” are “energy-detected by the on-chip WuRX in a backchannel communication-like approach”);
a sync receiver enabled by the wake-up receiver upon reception of the two pre-specified WiFi compatible packets, the sync receiver including circuitry to detect a payload packet and create a backscatter enable signal synced with a payload of the payload packet (disclosed throughout; see the fourth paragraph of column 1 on page 312, which indicates that “After wake-up and synchronization, the tag counts for a pre-specified amount of time until the payload of the incident WiFi signal begins to be received at the tag’s antenna”; thus the tag device detects when the payload of the incident WiFi signal begins; after the payload has been detected, this portion of the circuitry enables backscattering of the payload by triggering mixing the baseband data as indicated in the fourth paragraph of column 1 on page 312); and
a backscatter transmitter enabled by the backscatter enable signal (disclosed throughout; see Figure 20.1.3; further, see the second paragraph of column 1 on page 312, which indicates that after waiting for the header to pass, the IoT “backscatters during the payload”; see also the second paragraph of column 1 on page 312, which indicates that when the payload is detected, the IoT tag utilizes “an IQ mixer driving multi-phase-terminated backscatter switches to enable single-side-band (SSB) QPSK modulation to a single adjacent WiFi channel”).
Regarding claim 2: Wang discloses the limitation that the sensing comprises using a counter to measure the length of two pre-specified WiFi compatible packets that define the wake-up signal (disclosed throughout; see the correlator in the third paragraph of column 1 on page 312 and in Figure 20.1.2, which decides when the pre-specified-length packets have been received; as indicated in [0041] of Applicant’s specification, the claimed counter may be implemented by a correlator (144)).
Regarding claim 3: Wang discloses the limitation that a detection window is opened after receiving a first of the two pre-specified WiFi compatible packets is detected (disclosed throughout; as indicated in the fourth paragraph of column 1 on page 312, the IoT tag waits until the payload is detected to perform backscattering of the tag’s baseband; this is interpreted as a detection window and occurs after the first of the two pre-specified WiFi packets is detected).
Regarding claim 4: Wang discloses the limitation that the sync stage is enabled only if a second of the two pre-specified WiFi compatible packets is detected within the detection window (disclosed throughout; see the fourth paragraph of column 1 on page 312, which indicates that “After wake-up and synchronization, the tag counts for a pre-specified amount of time until the payload of the incident WiFi signal begins to be received at the tag’s antenna”; thus the tag device has a processing stage (sync stage) that senses when the payload of the incident WiFi signal begins; as indicated in the third paragraph of column 1 on page 312, this stage is enabled only after both of the two pre-specified-length packets is detected).
Regarding claim 5: Wang discloses the limitation that the sync stage uses a preamble and header of the payload packet to sync the backscatter transmission circuit with a payload of the payload packet (disclosed throughout; see the fourth paragraph of column 1 on page 312 and the second paragraph of column 2 on page 312, which disclose that the sync stage of the tag counts a pre-specified amount of time until the payload begins; this pre-specified amount of time is the time to let the preamble and header “pass” and thus the tag uses the preamble and header by waiting until they pass to trigger the backscattering of the tag’s baseband).
Regarding claim 6: Wang discloses the limitation of reflecting the payload packet by encoding data from the tag device such that the reflected signal follows the Wi-Fi standard can be decoded by another WiFi-device (disclosed throughout; see the second paragraph of column 2 on page 312, which discloses that “an incident…WiFi signal at channel 6…can be reflected to either channel 1 or 11…”; see also the second paragraph of column 1 on page 312, which indicates that the receiving AP uses “commercial WiFi” to receive the reflected signal and determine the backscattered alteration).
Regarding claim 8: Wang discloses the limitation that the wake-up receiver comprises a passive envelope detector that demodulates a signal, baseband signal filtering, an oversampling analog to digital converter and a packet length counter for detection of two pre-specified WiFi compatible packets (see Figure 20.1.2; see also the third paragraph of column 1 on page 312, which indicates that the “WuRX consists of an impedance transformer and a passive pseudo-balun envelope detector (ED), followed by an oversampled comparator and 11b digital correlator with soft-decision decoding to enable robust detection of the pre-specified WiFi signature”; the processing is performed in the digital domain and thus converted from analog and the backscattered signal is modulated using a baseband portion of the signal).
Regarding claim 9: Wang discloses the limitation that the passive envelope detector consumes zero power (disclosed throughout; see the third paragraph of column 1 on page 312, which indicates that the envelope detector is passive and thus does not consume power).
Regarding claim 10: Wang discloses the limitation that the only power consumed by the wake-receiver after receiving a first one of the two pre-specified WiFi compatible packets is consumed by the analog to digital converter the packet length counter and a clock generator (see Figure 20.1.2, which discloses that until the wake-up signal (both pre-specified-length WiFi packets) is received, the only power consumed is by the wake-up receiver, including the analog to digital converter and the correlator/counter, and the clock generator).
Regarding claim 12: Wang discloses the limitation of a wake-up enable switch from the packet length counter to enable the synchronization receiver upon detection of the second of two pre-specified WiFi compatible packets (disclosed throughout; see Figure 20.1.2, which discloses a wakeup signal from the baseband correlator that triggers the TX EN and switch when the two WiFi packets P0 and P1 are detected).
Regarding claim 13: Wang discloses the limitation of a backscatter enable switch from the synchronization receiver to enable a backscatter modulator in sync with the payload of the payload packet (disclosed throughout; see the fourth paragraph of column 1 on page 312, which discloses that “the tag counts for a pre-specified amount of time until the payload of the incident WiFi signal begins to be received at the tag’s antenna. The most basic way to perform backscattering at this time would be to modulate a switch…”).
Regarding claim 14: Wang discloses the limitation of a front-end matching network that provides passive gain to a received signal (see the passive voltage gain in Figure 20.1.2, for example).
Regarding claim 15: Wang discloses the limitation that the passive envelope detector comprises a passive pseudo-balun envelope detector (see the fourth paragraph of column 1 on page 312, which discloses that the “WuRX consists of an impedance transformer and a passive pseudo-balun envelope detector (ED)”).
Regarding claim 17: Wang discloses the limitation that the wake-up receiver is always powered and the sync receiver is duty-cycled to be on only to enable and sync the backscatter receiver in timing with the payload (disclosed throughout; see Figure 20.1.2 and the second and third paragraphs of column 1 on page 312, which disclose that the wake-up receiver can receive the two pre-specified-length packets at any time and is thus always powered on to receive these wake-up packets; further, as indicated in Figure 20.1.2 and the fourth paragraph of column 1 on page 312, the sync receiver enabled to count the prespecified time until the payload is received after the wakeup packets have been detected).
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.
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.
Claim 11 is rejected under 35 U.S.C. 103 as being unpatentable over Wang et al (“28μW IoT Tag That Can Communicate with Commodity WiFi Transceivers via a Single-Side-Band QPSK Backscatter Communication Technique”) in view of Serizawa et al (US 2018/0302837).
Regarding claim 11: Wang discloses the limitations of parent claim 8 as indicated above. Wang further discloses the limitations of claim 11 that the counter is pre-coded with lengths of the two pre-specified WiFi compatible packets (see the third paragraph of column 1 on page 312, for example, which discloses “the incident WiFi TX send two pre-specified-length packets at a pre-specified separation, that are energy-detected by the on-chip WuRX in a backchannel communication-like approach”; clearly, the IoT tag is coded with these packet lengths to enable the detection of the packets as a pre-specified WiFi wakeup signature). Wang does not explicitly disclose the limitations of claim 11 that the lengths serve as an identity for the wake-up transceiver. However, Serizawa discloses a system that uses wakeup signals. Further, Serizawa discloses using a bit length of a packet as an identity for the user terminal (either the terminal ID or a broadcast ID). For example, see [0122] (“the address information can be the bit length of the wakeup packet”) as well as [0127]-[0128] and Figure 16. It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify Wang such that the lengths of the pre-specified WiFi packets serve as an identity as suggested by Serizawa. The rationale for doing so would have been to efficiently indicate the identity of the device suitable for low power wakeup receivers.
Claim 16 is rejected under 35 U.S.C. 103 as being unpatentable over Wang et al (“28μW IoT Tag That Can Communicate with Commodity WiFi Transceivers via a Single-Side-Band QPSK Backscatter Communication Technique”) in view of Kim et al (US 2018/0145632).
* Cited in Applicant’s IDS filed 1/26/2024.
Regarding claim 16: Wang discloses the limitations of parent claim 7 as indicated above. Wang does not explicitly disclose the limitations of claim 16 that the synchronization receiver comprises a low noise amplifier, an active envelope detector and an analog to digital converter. However, Kim discloses a similar system. Further, Kim [0006] discloses a receiver including “a clocked envelope detector (ED) configured to detect an envelope of the oscillation signal and hold a peak value of the envelope during a preset time interval, and an analog-to-digital converter (ADC) configured to convert the peak value of the envelope into a digital signal”. Further, in [0025], Kim discloses that the receiver may also include “a low noise amplifier (LNA)”. It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify the synchronization receiver of Wang to include a low noise amplifier, an active envelope detector, and an ADC as suggested by Wang. The rationale for doing so would have been to more accurately detect the signal as suggested in [0004] of Kim, for example.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Haque et al (US 11,956,725) discloses a network initiated method for on-demand zero-energy paging.
Sundaresan et al (US 11,620,462) discloses a method for reading passive wireless tags using commodity devices.
Katan Baf Nezhad et al (US 11,503,545) discloses a method for wakeup messaging for backscatter communications.
Karimaruthumkal et al (US 2021/0368439) discloses a WLAN wakeup radio with backscattering that uses a WUR trigger packet to trigger the backscattering.
Gollakota et al (US 2017/0180075) discloses wireless communication devices operable using harvested power.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Robert C Scheibel whose telephone number is (571)272-3169. The examiner can normally be reached Monday-Friday 8:00 AM - 5:00 PM.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Hassan A Phillips can be reached at 571-272-3940. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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Robert C. Scheibel
Primary Examiner
Art Unit 2467
/Robert C Scheibel/Primary Examiner, Art Unit 2467 January 8, 2026