System and method for transmitting data in wireless communication network

Abstract

A system and method for transmitting data in a wireless communication network is disclosed. The method includes: receiving a bitstream including environmental Internet of Things (A-IoT) data from a network node; generating an on-off keying (OOK)-1 or OOK-4 modulated waveform; generating a cyclic prefix (CP) by replicating one or more samples of a first OOK chip in the waveform; adding the CP at the starting end of a first OOK chip in the waveform; and transmitting the waveform with the additional CP to one or more A-IoT devices on a wireless channel.

Description

[0001] This application claims priority to U.S. Provisional Application No. 63 / 642,125, filed May 3, 2024, and U.S. Non-Provisional Application No. 19 / 195,289, filed April 30, 2025, the disclosures of which are incorporated by reference in their entireties, as if fully set forth herein. TECHNICAL FIELD

[0002] The present disclosure relates generally to wireless communication systems. More specifically, the subject matter disclosed herein relates to improvements to cyclic prefix (CP) processing techniques for orthogonal frequency-division multiplexing (OFDM)-based on-off keying (OOK) waveforms in ultra-low power device communications, such as ambient Internet of Things (A-IoT) systems. BACKGROUND

[0003] Wireless communication systems increasingly support ultra-low power devices (e.g., user equipment (UE)) such as those used in A-IoT applications. In these systems, OFDM-based OOK waveforms are used as a downlink transmission scheme due to their compatibility with simple envelope detection at the receiver. To support these waveforms, a CP is inserted at the transmitter to mitigate inter-symbol interference (ISI) and facilitate synchronization.

[0004] OFDM-based systems can generate a CP by copying the last portion of a time-domain OFDM symbol and appending the last portion to the beginning of the symbol. While effective for fast Fourier transform (FFT)-based OFDM receivers, this approach can introduce unintended rising or falling edges in the signal envelope when used with OOK waveforms. These false transitions can degrade the envelope detection performance in low-complexity A-IoT devices, particularly under conditions of large sampling frequency offset (SFO). SUMMARY

[0005] One problem with the above approach is that the CP, when formed by copying the end of the OFDM symbol, can cause unwanted transitions at the boundary between symbols. These transitions mimic valid signal activity and can be erroneously interpreted by an envelope detector as data.

[0006] To overcome these problems, systems and methods are described herein for generating a CP in an OFDM-based OOK waveform by copying samples from the beginning of a first OOK chip in the OFDM symbol, rather than the end. The CP is inserted before the OFDM symbol to avoid introducing artificial edges at the symbol boundary.

[0007] Further, the systems and methods described herein include adjusting a duration of the first OOK chip to ensure uniform length between all OOK chips within the OFDM symbol, preserving timing alignment at chip level.

[0008] The above ways improve previous methods as they reduce the generation of false signal jumps that impair envelope detection accuracy. By tailoring the CP insertion to the characteristics of the OOK waveform and the constraints of low-power A-IoT receivers, the disclosed technology enhances signal integrity while minimizing receiver complexity and sensitivity to synchronization errors.

[0009] According to an embodiment, a method for transmitting data in a wireless communication network is provided. The method includes transmitting, by a network node, a bitstream comprising A-IoT data; generating a waveform modulated with OOK-1 or OOK-4; generating a CP by duplicating one or more samples of a first OOK chip in the waveform; appending the CP at a beginning of the first OOK chip in the waveform; and transmitting the waveform with the appended CP to one or more A-IoT devices over a wireless channel.

[0010] According to another embodiment, a system for transmitting data in a wireless communication network is provided. The system includes a radio frequency (RF) front end and a processor configured to: receive a bitstream comprising A-IoT data; generate a waveform modulated with OOK-1 or OOK-4; generate a CP by duplicating one or more samples of a first OOK chip in the waveform; append the CP at a beginning of the first OOK chip in the waveform; and cause the RF front end to transmit the waveform with the appended CP to one or more A-IoT devices.

[0011] According to another embodiment, a non-transitory computer-readable medium storing instructions is provided. The instructions, when executed by a processor, cause the processor to: receive a bitstream comprising ambient Internet of Things (A-IoT) data; generate a waveform modulated with OOK-1 or OOK-4; generate a CP by duplicating one or more samples of a first OOK chip in the waveform; append the CP at a beginning of the first OOK chip in the waveform; and cause transmission of the waveform with the appended CP to one or more A-IoT devices over a wireless channel. BRIEF DESCRIPTION OF DRAWINGS

[0012] In the following detailed description, various aspects of the subject matter described herein will be described referring to exemplary embodiments illustrated in the drawings, wherein:

[0013] Figure 1 A transmitting device or a receiving device in a communication system according to an embodiment is shown;

[0014] Figure 2 shows an architecture of a CP-OFDM transmitter according to an embodiment;

[0015] Figure 3 shows an architecture of a CP-OFDM receiver according to an embodiment;

[0016] Figure 4 shows CP insertion in an OFDM symbol according to an embodiment;

[0017] Figure 5 shows an architecture for generating an OFDM-based OOK-1 waveform according to an embodiment;

[0018] Figure 6 shows an architecture for generating an OFDM-based OOK-4 waveform according to an embodiment;

[0019] Figure 7 shows an example architecture of an ultra-low power A-IoT device in a first class of devices according to an embodiment;

[0020] Figure 8 shows an example architecture of an ultra-low power A-IoT device with a RF-ED receiver in a second class of devices according to an embodiment;

[0021] Figure 9 shows an example architecture of an ultra-low power A-IoT device with a RF-ED receiver in a second class of devices according to an embodiment;

[0022] Figure 10 shows the effect of CP insertion into an OFDM symbol carrying multiple OOK chips according to an embodiment;

[0023] Figure 11 shows the impact of CP insertion on OOK signal waveform according to an embodiment;

[0024] Figure 12 is a block diagram of a signal generation architecture at a reader configured to support both cellular transmission paths and A-IoT transmission paths according to an embodiment;

[0025] Figure 13 is a flowchart showing a method for CP processing and waveform generation for OFDM-based OOK transmission according to an embodiment;

[0026] Figure 14 is a block diagram of an electronic device in a network environment according to an embodiment; and

[0027] Figure 15 is a system comprising a UE and a base station gNB in communication with each other according to an embodiment. DETAILED DESCRIPTION

[0028] In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the disclosure. However, it will be understood by those skilled in the art that the disclosed aspects can be practiced without these specific details. In other instances, well-known methods, procedures, components and circuits have not been described in detail so as not to obscure the subject matter disclosed herein.

[0029] Reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the disclosure. Thus, the appearances of the phrase “in one embodiment” or “in an embodiment” or “according to one embodiment” (or other phrases of similar meaning) throughout this specification on various places does not necessarily all refer to the same embodiment. Furthermore, the particular features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. In this regard, the term “exemplary” as used herein means “serving as an example, instance, or illustration.” Any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments. Additionally, particular features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. Similarly, a hyphenated term, as used herein, can occasionally be used in conjunction with the corresponding non-hyphenated version of the term, and vice versa, to indicate that the two versions of the term, independently of one another, are also individually applicable to the same or like aspects of an embodiment of the present disclosure. Such occasional use of a hyphenated term along with its un-hyphenated version or vice versa, is for the purpose of expediency and / or readability, only, and is in no way intended to limit the term in question to multiple-word versions only, or to only a single-word version, of the term.

[0030] Furthermore, according to the context in which the terms are discussed herein, singular terms can include their corresponding plural forms and plural terms can include their corresponding singular forms. It will be further understood that the various drawings described herein are not drawn to scale and that elements of similar structures or functions are generally given the same reference numerals.

[0031] The terminology used herein is for the purpose of describing some example embodiments only and is not intended to be limiting of the claimed subject matter. As used herein, the singular forms “a,” “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and / or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0032] It will be understood that when an element or layer is referred to as being “on” or “connected to” or “coupled to” another element or layer, it can be directly on, connected or coupled to the other element or layer or intervening elements or layers can be present. In contrast, when an element is referred to as being “directly on,” or “directly connected to” or “directly coupled to” another element or layer, there are no intervening elements or layers present. Like reference numerals refer to like elements throughout the specification. As used herein, the term “and / or” includes any and all combinations of one or more of the associated listed items.

[0033] As used herein, the terms “first,” “second,” and the like, are used as labels for nouns that they follow and do not necessarily describe any type of ordering, such as a spatial, temporal, logical, or other ordering. Moreover, two or more terms used herein can be used interchangeably in some contexts while in other contexts, one or more of these terms can be preferred over another. Also, spatially relative terms, such as “beneath,” “below,” “lower,” “above,” “upper,” and the like, can be used herein for ease of description to describe one element or feature’s relationship to another element(s) or feature(s) as illustrated in the figures. The spatially relative terms are intended to encompass different orientations of the device in use or

[0034] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this subject matter belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0035] As used herein, a “bitstream” refers to a sequence of binary values (e.g., 0s and Is) representing encoded information to be transmitted using a communication waveform. The bitstream can be mapped to one or more symbols (e.g., OOK chips) in a time domain waveform, which are then modulated onto one or more subcarriers in a multi-carrier modulation scheme, such as OFDM.

[0036] As used herein, an “OOK chip” refers to a segment of a time domain waveform that uses the presence or absence of a carrier signal to represent binary data. For example, an “on” state can represent a binary “1” and is implemented by transmitting energy on a designated subcarrier, while an “off’ state can represent a binary “0” and is implemented by not transmitting energy (e.g., zero signal amplitude). In some embodiments, a single OOK chip (OOK-1) can occupy the entire OFDM symbol duration, while in other embodiments, multiple OOK chips (OOK-M) can occupy a single OFDM symbol, where M > 2.

[0037] “CP” as used herein refers to a segment of time-domain samples appended to the beginning of an OFDM symbol to extend its duration. The CP is typically generated by copying a portion of samples from the OFDM symbol, and it serves to mitigate ISI caused by multipath propagation. In the context of OFDM-based OOK waveforms, the CP can be generated differently (e.g., using samples from the beginning of an OOK chip) to avoid introducing spurious rising or falling edges that degrade envelope detection performance in ambient-IoT receivers.

[0038] “Samples from the first OOK chip within an OFDM symbol” as used herein refers to a subset of time-domain samples corresponding to the beginning portion of the first OOK chip embedded within an OFDM symbol. These samples can be used to generate a CP by duplication and prepend to the OFDM symbol, resulting in a waveform with continuous amplitude jumps at symbol boundaries and reduced appearance of spurious edges.

[0039] “OFDM symbol with appended CP” as used herein refers to a complete time-domain signal corresponding to a single OFDM symbol, including a CP segment and the main OFDM symbol body following the CP segment. The CP can be constructed in various ways (such as by copying a segment from the beginning or end of the OFDM symbol) depending on the intended properties (such as minimizing envelope discontinuities in OOK-based signaling).

[0040] “A-IoT device” as used herein refers to a super-low-power wireless device forming part of an A-IoT network. These devices are designed with minimal complexity and can operate using energy harvested from the environment. A-IoT devices typically include a simplified receiver chain (such as an envelope detector that does not perform Fast Fourier Transform (FFT) processing), and are optimized for low duty-cycle, low-data-rate communication using amplitude-shift keying schemes such as OOK on OFDM waveforms.

[0041] Figure 1 A transmitting device or a receiving device in a communication system according to an embodiment is shown.

[0042] Reference is made to Figure 1 The device 100 can be used as a UE (such as a client device), or as a base station (gNB). The device 100 includes a controller module 101 (e.g., one or more processors), a storage module 102, and an antenna module 103 for generating and / or receiving OFDM-based OOK waveforms with CP processing as described herein.

[0043] The controller module 101 performs primary processing tasks and manages device operations. It can include a processor dedicated to specific tasks, such as digital signal processing (DSP), for handling signal conditioning, demodulation, synchronization, and envelope detection-based reception techniques suitable for ultra-low power consumption environment IoT devices. The DSP can employ advanced computational techniques, such as FFT, inverse FFT (IFFT), and digital filtering, to ensure reliability and accuracy of signals processed for downlink transmissions using OFDM-based OOK waveforms.

[0044] In some embodiments, the controller module 101 can also generate a CP by copying a portion of the first OOK chip in the OFDM symbol and appending the portion to the beginning of the OFDM symbol to reduce unwanted edge transitions.

[0045] The storage module 102 can include transitory or non-transitory memory for storing executable instructions, signal generation parameters, CP configuration data, and waveform construction logic for OOK transmission and detection. The stored instructions can include instructions necessary to run the processes described herein, such as generating OOK-1 or OOK-4 symbols with adjusted CP placement to maintain uniform chip timing across OFDM symbols. The storage module 102 can also incorporate a communication protocol stack, including layers such as physical (PHY), medium access control (MAC), radio link control (RLC), and packet data convergence protocol (PDCP).

[0046] The antenna module 103 can include one or more antennas responsible for transmitting and receiving wireless signals between the device 100 and other network components, such as UEs or gNBs. The antenna module 103 can receive wireless signals from a base station, convert these signals into electrical signals suitable for processing, and transmit data from the device to other nodes within the network, including performing low-complexity downlink reception using envelope detection.

[0047] The various embodiments disclosed herein provide systems and methods for CP insertion for OFDM-based OOK waveforms at a transmitting device. In particular, a CP can be generated by copying the first N CP samples of a first OOK chip within an OFDM symbol and inserting these samples at the beginning of the same OOK chip, where N CP represents the length of the CP.

[0048] The Internet of Things (IoT) has become an increasingly important area of focus in wireless communication systems. Increasing numbers of connected devices or "things" are being deployed to improve operational efficiencies, enable automation, and improve overall quality of life. To support the broad adoption of IoT across a variety of industries and environments, there is a continuing need to reduce the size, complexity, and power consumption of IoT devices. These reductions are expected to enable massive deployments involving hundreds or even trillions of devices.

[0049] For many use cases, reliance on batteries that need to be replaced or manually charged on a regular basis is impractical. Battery maintenance can result in high operational costs, environmental impact, and safety risks, particularly in scenarios such as remote sensors in mission-critical infrastructure (e.g., power or oil systems). To address these issues, devices that do not have energy storage or have limited and non-replaceable energy storage can instead rely on energy harvesting. However, energy harvesters typically produce only a few hundred microwatts (pW) or less, which is insufficient to support the milliwatt-level peak power consumption of conventional cellular devices.

[0050] Due to the limitations of existing technologies, new IoT system designs are being developed to meet the needs of emerging use cases. These new systems are envisioned to operate with significantly reduced complexity and power requirements, thereby supporting massive connection densities while enabling low-cost, low-maintenance operation. For example, within the Third Generation Partnership Project (3GPP) framework, A-IoT communication configurations are being established that can operate with several orders of magnitude lower power consumption and system complexity than existing low-power wide-area (LPWA) technologies, such as Narrowband IoT (NB-IoT) and enhanced Machine Type Communications (eMTC).

[0051] Figure 2 An architecture of a CP-OFDM transmitter according to an embodiment is shown.

[0052] Reference is made to Figure 2 The transmitter includes a modulator 201, a serial-to-parallel (S / P) converter (or S / P) 202, an IFFT block (or IFFT) 203, a parallel-to-serial (P / S) converter (or P / S) 204, a CP insertion block (or CP insertion) 205, and an RF front end (or RF) 206. The modulator 201 generates modulation symbols for transmission, which are then converted to parallel streams by the S / P converter 202. The IFFT block 203 transforms the frequency-domain data to the time domain, resulting in a time-domain OFDM symbol that spans multiple subcarriers.

[0053] The time-domain output from the IFFT block 203 is then serialized by the P / S converter 204. The serialized data is passed to the CP insertion block 205, which appends a CP to each OFDM symbol. In some OFDM systems, the CP is generated by copying the last portion of the IFFT output and placing it at the beginning of each OFDM symbol. This operation serves to mitigate ISI caused by multipath propagation and to preserve orthogonality between subcarriers during FFT-based demodulation at the receiver. The CP-enhanced OFDM signal is passed to the RF front-end 206 for analog processing and transmission over the air.

[0054] Figure 3 An architecture of a CP-OFDM receiver according to an embodiment is shown.

[0055] Reference is made to Figure 3 The receiver comprises a RF front-end 301, a CP removal block (or CP removal) 302, a S / P converter 303, a FFT block (or FFT) 304 and a demodulator 305.

[0056] The RF front-end 301 receives an analog OFDM signal over the air and performs down-conversion and analog-to-digital conversion. The digitized signal is passed to the CP removal block 302, which discards the first N CP samples of each OFDM symbol, where N CP corresponds to the length of the CP. This removal ensures that only the ISI-free portion of the signal is kept for subsequent processing.

[0057] The resulting data is converted from serial to parallel format by the S / P converter 303, and then processed by the FFT block 304, which transforms the signal from time to frequency domain. After the FFT operation, redundant or unused subcarriers can be discarded and the remaining frequency-domain symbols are demodulated by the demodulator 305 to recover the transmitted data.

[0058] In the fifth generation (5G) New Radio (NR) system, a CP is inserted before each OFDM symbol in time domain to improve robustness to multipath propagation.

[0059] Figure 4 CP insertion in an OFDM symbol according to an embodiment is shown.

[0060] Reference is made to Figure 4 The CP 401 is generated by copying the last portion of the OFDM symbol, specifically the last N CP samples, and appending them to the beginning of the symbol. This forms an extended time-domain signal that includes a CP interval TCP (or referred to as CP duration T CP ) and a useful OFDM symbol interval T CP after the CP interval T U .

[0061] The insertion of the CP has two functions. First, the CP acts as a guard interval that absorbs a delayed version of the transmitted signal, thereby preventing ISI at the receiver. To ensure ISI mitigation, the CP duration T CP is chosen to be longer than the maximum expected delay spread of the channel impulse response. Second, by repeating a portion of the OFDM symbol, the CP converts the linear convolution of the transmitted signal with the channel to a circular convolution. This transformation allows the use of FFT-based demodulation techniques at the receiver, enabling the signal to be efficiently processed as a collection of parallel frequency-flat sub-channels.

[0062] To support improved UE energy efficiency, a low-power wake-up receiver (LP-WUR) and low-power wake-up signal (LP-WUS) can be used by applying an OOK-1 waveform structure and an OOK-4 waveform structure. These waveforms are based on OOK modulation and are designed to support low-complexity detection of energy-constrained UEs in A-IoT scenarios.

[0063] Figure 5 An architecture for generating an OFDM-based OOK-1 waveform according to an embodiment is shown.

[0064] Referring to Figure 5 , the system comprises a K-point upsampling block (or referred to as K upsampling) 501, a pulse shaping block (or referred to as pulse shaping) 502, an S / P converter 503, an IFFT block (or referred to as N-point IFFT (block)) 504, a P / S converter 505, a CP insertion block 506 and an output buffer for IFFT signal (or referred to as IFFT output) 507.

[0065] The OOK-1 waveform is designed to transmit a single bit per OFDM symbol using OKK modulation. In case of an “on” bit, all K designated subcarriers are modulated with energy; for an “off” bit, the subcarriers are left empty, corresponding to zero baseband power.

[0066] Referring to Figure 5 , to start the waveform generation, the bit stream is upsampled by the K-point upsampling block 501 and can be pulse shaped using the pulse shaping block 502 to manage parameters such as peak-to-average power ratio (PAPR) and dynamic range. The signal is then mapped onto the designated K subcarriers via S / P conversion by the S / P converter 503.

[0067] The resulting frequency domain signal is transformed to the time domain using an N-point IFFT block 504. The time domain samples are then serialized by a P / S converter 505 and passed to a CP insertion block 506 which appends a CP to the beginning of the time domain signal. The final output comprises the CP portion and the IFFT output 507 following the CP portion in preparation for RF transmission.

[0068] Figure 6 An architecture for generating an OFDM-based OOK-4 waveform is shown in accordance with an embodiment.

[0069] Referring to Figure 6 , the system comprises a K-point upsampling block 601, a pulse shaping block 602, an S / P converter 603, an MK-point Discrete Fourier Transform (DFT) or least squares transform block (or MK-point DFT or least squares for short) 604, an IFFT block 605, a P / S converter 606, a CP insertion block 607 and an output buffer for the IFFT signal 608.

[0070] OOK-4 waveforms are a more complex OOK structure compared to OOK-1. Instead of transmitting a single OOK bit per OFDM symbol, OOK-4 transmits multiple OOK chips within a single OFDM symbol interval. Specifically, the system transmits a sequence of "on" or "off states on the subcarriers allocated to OOK-4, enabling multiple bits to be encoded per OFDM symbol.

[0071] Referring to Figure 6 , the input sequence of M OOK chips is first upsampled by the K-point upsampling block 601. In order to prepare the signal for frequency domain mapping, an optional pulse shaping can be applied using the pulse shaping block 602, although the DFT stage itself can inherently provide sufficient spectral shaping. The signal is then serialized and converted to parallel streams by the S / P converter 603.

[0072] Next, the MK-length signal is processed by the DFT or least squares transform block 604 to map the signal onto the frequency domain. The DFT is widely used in practice due to its computational efficiency and the similarity of its output to least squares estimates. The resulting frequency domain signal is passed through the IFFT block 605 to obtain the corresponding time domain representation.

[0073] The time domain signal is serialized by the P / S converter 606 and passed to the CP insertion block 607 which appends a CP to the beginning of each OFDM symbol. The final output comprises the CP and the IFFT output 608 following the CP, forming a complete baseband waveform suitable for RF transmission.

[0074] In certain embodiments, receiver devices configured for A-IoT communication can operate under strict power constraints and simplified hardware architecture while still supporting robust downlink detection of OOK waveforms. Depending on system implementation and use case requirements, A-IoT devices can be classified into multiple categories based on their peak power consumption profiles and transmission capabilities.

[0075] The first category of devices can operate with ultra-low peak power consumption on the order of 1 microwatt. These devices can include minimal energy storage and exhibit initial SFO values up to tens of parts per million. Such devices typically omit both downlink and uplink amplification circuitry and can rely on passive mechanisms, such as backscatter communication for uplink transmission. The uplink signal in this implementation can be reflected from an externally provided continuous wave (CW) carrier signal.

[0076] The second category of devices can operate with a modestly higher peak power budget, such as on the order of a few hundred microwatts. These devices can also include energy storage and support similar SFO tolerances. However, they are also equipped with downlink and / or uplink amplification capabilities. Depending on the design, UL transmission can be implemented using active radio transmissions generated by the device itself or using passive backscatter of an externally provided CW carrier.

[0077] These architecture classifications help define the power envelope and complexity budget for various A-IoT receiver implementations. In all cases, the receiver architecture can include a low complexity envelope detector configured to process OOK modulated signals transmitted using OFDM-based signaling formats, such as OOK-1 or OOK-4 waveforms. To ensure robust detection in the presence of SFO, multipath, and limited hardware resources, waveform design and CP insertion techniques can be adapted to the capabilities and constraints of these device types.

[0078] Figure 7 An example architecture of an ultra-low power A-IoT device in the first category of devices is shown in accordance with an embodiment.

[0079] The functionality of the device receiver includes envelope detection that converts an RF or intermediate frequency (IF) signal to baseband based on passive components, such as diodes, resistors, and capacitors. The envelope detector can achieve relatively low power consumption. To support RF envelope detection at the A-IoT device, OOK is used for downlink transmission.

[0080] Reference is made to Figure 7The apparatus 700 includes a matching network 701, an RF energy harvester 702, a power management unit (PMU) 703, and an energy storage module (or referred to as energy storage) 704. The matching network 701 is coupled to an antenna and connected to the RF energy harvester 702. The energy harvester 702 powers the power management unit (PMU) 703 and the energy storage module 704 for self-sustained operation. The apparatus 700 can also include an RF receive path. The RF receive path includes an RF bandpass filter (RF BPF) 705, an RF envelope detector 706, and a baseband lowpass filter (BB LPF) 707. The apparatus 700 can also include a comparator 708 and a baseband (BB) logic 709. The comparator 708 processes the filtered signal and outputs the processing result to the BB logic 709. The BB logic 709 includes a decoder, a controller, and an encoder, and interfaces with a memory module (or referred to as memory) 710 included in the apparatus 700.

[0081] The apparatus 700 can also include a clock generator 711. The clock generator 711 provides timing signals for internal processing. For uplink transmission, the apparatus 700 includes a backscatter modulator 712 that performs impedance switching to modulate an externally provided carrier.

[0082] The receiver architecture is configured for OOK reception only and does not perform OFDM demodulation or FFT-based processing. As a result, the CP used in the downlink signal does not need to preserve the circular convolution property that is typically required for FFT-based demodulation to convert a linear convolution to a circular convolution. Instead, the CP can be specifically adapted to OOK envelope detection. Given that these apparatuses can operate with a significant SFO, such as 10% or more, it is particularly advantageous to structure the CP to avoid introducing unintended rising or falling edges in the time-domain signal that can otherwise trigger false detections or degrade performance.

[0083] Figure 8 An example architecture of a super low power A-IoT apparatus with RF-ED receiver in a second class of apparatuses according to an embodiment is shown.

[0084] Reference is made to Figure 8 The apparatus 800 includes a matching network 801 coupled to an antenna, an optional RF energy harvester 802, a PMU 803, and an energy storage module 804. In some embodiments, the apparatus 800 can also include an additional energy harvester 805 that is not based on RF energy, which can supplement the power to the energy storage apparatus.

[0085] The apparatus 800 can also include a receiver chain. The receiver chain includes an RF BPF 806, and optionally a low noise amplifier (LNA) 807. The apparatus 800 can also include an RF envelope detector 808 and a baseband amplifier (BB amp) 809. The RF envelope detector 808 extracts the signal envelope, which is then amplified by the BB amp 809. The output is filtered through a BB LPF 810 included in the apparatus 800, and digitized through a comparator or N-bit analog-to-digital converter (ADC) 811 included in the apparatus 800.

[0086] The apparatus 800 can also include digital baseband (BB) logic 812 and a memory 813. The digital baseband logic 812 includes decoders, controllers, and encoders, and interfaces with the memory 813. The apparatus 800 can also include a clock generator 814. The clock generator 814 provides timing signals for digital operations. For uplink signaling, the apparatus 800 includes a backscatter modulator 815 that performs impedance switching, and a reflection amplifier 816 for boosting the backscatter signal. In some implementations, the apparatus 800 optionally includes a large frequency shifter 817 for generating an uplink signal distinguishable from a downlink signal.

[0087] In comparison to the apparatus 700, the apparatus 800 includes additional amplification capabilities in both the downlink path and the uplink path, enabling improved signal strength and flexibility. However, the apparatus can still operate without full-FFT based OFDM demodulation. As with the apparatus 700, the apparatus 800 can rely on envelope detection to receive OOK waveforms, benefiting from the waveform design and CP structure that minimizes false edges in the presence of large SFO and keeps detection robust.

[0088] Figure 9 An example architecture of an ultra-low power A-IoT device with RF-ED receiver in a second class of devices according to an embodiment is shown.

[0089] Referring to Figure 9 The apparatus 900 includes a matching network 901 coupled to an antenna, an optional RF energy harvester 902, a PMU 903, and an energy storage module 904. In some embodiments, the apparatus 900 can also include an additional energy harvester 905 that is not based on RF energy, which can supplement the power to the energy storage device.

[0090] The apparatus 900 can also include a receiver chain. The receiver chain includes an RF BPF 906, and optionally an LNA 907. The apparatus 900 can also include an RF envelope detector 908 and a BB amp 909. The RF envelope detector 908 extracts the signal envelope, which is then amplified by the BB amp 909. The output is filtered by a BB LPF 910 included in the apparatus 900, and digitized by a comparator or N-bit ADC 911 included in the apparatus 900.

[0091] The apparatus 900 can also include digital baseband (BB) logic 912 and memory 913. The digital baseband logic 912 includes decoders, controllers, and encoders, and interfaces with the memory 913. The apparatus 900 can also include a clock generator 914. The clock generator 914 provides timing signals for digital operations. For uplink signaling, the apparatus 900 includes a full RF transmitter, which includes a transmit (Tx) modulator 915, a digital-to-analog converter (DAC) 916, an LPF 917, a mixer, and a local oscillator (LO) such as a phase-locked loop (PLL) or a frequency-locked loop (FLL). The apparatus 800 optionally includes a power amplifier (PA) 918, which boosts the RF output signal before transmission.

[0092] The architecture differs from that of the apparatus 800 in that it includes a fully integrated transmitter capable of independently generating and radiating an uplink signal, rather than relying on backscatter modulation. However, similar to the apparatus 800, the receiver chain is based on envelope detection, and does not perform FFT-based OFDM demodulation, making it compatible with the OOK waveform reception techniques described herein.

[0093] The A-IoT receiver architectures described herein, including those of the apparatus 700, apparatus 800, and apparatus 900, differ from conventional CP-OFDM receiver architectures. In traditional systems, the received signal is amplified by an LNA, followed by CP removal and frequency-domain processing using an FFT. In contrast, the A-IoT receivers described in this disclosure omit CP removal and FFT entirely. Instead, the signal is passed directly to an envelope detector immediately after the LNA.

[0094] This design choice is implemented by using amplitude-shift keying (ASK) modulation in the form of OOK waveforms, such as OOK-1 and OOK-4. As Figure 5 and Figure 6As shown, these waveforms produce time-domain signals that resemble traditional OOK signals with clearly distinguishable "on" and "off" states. As a result, simple envelope detection techniques can be used to extract the relevant information without the need for frequency-domain processing or demodulation. This enables a significant reduction in receiver complexity and power consumption, making this architecture well-suited for ultra-low power A-IoT deployments.

[0095] In various embodiments, downlink signaling from an A-IoT reader to a device (R2D) can be based on an OFDM-based waveform structure. The waveform can be designed to support ultra-low power receivers that utilize ASK detection methods, such as OOK. From the downlink transmitter's perspective, the system can employ an OFDM-based waveform that supports modulation formats such as OOK-1 and OOK-4, where OOK-1 transmits a single OOK chip per OFDM symbol and OOK-4 transmits multiple OOK chips per OFDM symbol.

[0096] The structure of the OFDM waveform can be transparent to the A-IoT receiver. For example, the underlying OFDM signal can be generated using CP-OFDM, DFT-s-OFDM, or other OFDM variants, while the device uses a non-coherent method to detect the resulting signal envelope. Thus, the A-IoT device can remain agnostic to the specific waveform generation techniques used at the transmitter.

[0097] With respect to CP processing, different approaches can be considered to be compatible with envelope detection and simplified receiver design. One approach involves completely omitting CP removal at the receiver and relying on the waveform design to avoid introducing discontinuities at symbol boundaries. Another approach seeks to ensure that the insertion of the CP does not result in a false rising or falling edge at the jump between adjacent OOK chips, which can lead to incorrect detection. To address these issues, the CP can be constructed such that the jump from the last chip of a given OFDM symbol to the first chip of the next symbol is smooth and uniform, e.g., by aligning the chip lengths or replicating samples that avoid amplitude jumps.

[0098] Other considerations in the design and evaluation of the R2D waveform include the impact of the CP structure on timing acquisition and decoding performance, implementation complexity for both the reader and the device, interference management when operating in the licensed frequency spectrum band, and overall spectral efficiency. Multiple candidate CP processing strategies can be evaluated according to these factors to identify ways to optimize detection robustness while remaining compatible with the power and complexity constraints of the A-IoT receiver.

[0099] Both OOK-1 and OOK-4 waveforms can be used for R2D transmissions in an A-IoT system. For example, referring again to FIG. 1, the A-IoT reader 102 can transmit OOK-1 or OOK-4 waveforms to the A-IoT device 104, which can detect the transmitted waveforms using envelope detection techniques. Figure 5OOK-1 waveform transmits a single OOK chip per OFDM symbol. In this structure, a dedicated frequency domain sequence is mapped to K subcarriers for the "on" state, while 0 is assigned to the same set of carriers for the "off" state. The mapped subcarriers are transformed to the time domain using IFFT, and then CP insertion is performed to form the final baseband signal.

[0100] Alternatively, in the case of Figure 6 OOK-4 waveform enables multiple OOK chips to be embedded within a single OFDM symbol. In this case, a sequence of M OOK chips is first upsampled and optionally shaped, and then processed using DFT or least square optimization methods to generate a frequency domain signal. This signal can be optionally truncated or further adjusted across K subcarriers. The resulting frequency domain vector is transformed by IFFT, and then a CP is inserted at the beginning of the time domain output to complete the waveform.

[0101] When generating A-IoT downlink signals using OOK-1 or OOK-4 waveform, CP-OFDM signal generation methods based on the architecture shown in Figure 5 and Figure 6 may be used. The bit stream can be mapped to frequency domain subcarriers, transformed via IFFT, and appended with a CP that is generated by copying the last N CP samples of the IFFT output and inserting them at the beginning of the time domain signal.

[0102] While this technique is consistent with existing cellular transmission handling, it can lead to unintended consequences when received by A-IoT devices configured for envelope detection, such as device 700, device 800, or device 900 shown in Figure 7 , Figure 8 and Figure 9 respectively. In particular, the addition of the CP can result in discontinuities or sharp jumps at the boundary between the CP and the beginning of the OFDM symbol. These jumps can manifest as spurious rising or falling edges in the received envelope, potentially leading to unwanted chip detection.

[0103] Figure 10 Effects of inserting a CP into an OFDM symbol carrying multiple OOK chips are shown in accordance with an embodiment.

[0104] Reference is made to Figure 10, showing the time-domain signal including four OOK chips (e.g., bit sequence "0101") before CP insertion. Upon appending the CP formed by copying the last part of the symbol, a discontinuity is introduced at the junction between the CP and the beginning of the OFDM symbol. This causes an unintended rising edge that does not correspond to an actual data transition, and can trigger false detection events in receivers that rely on envelope-based decision logic.

[0105] One possible mitigation strategy is to remove the CP at the receiver. However, this requires accurate identification of the CP boundary within each symbol. Given that A-IoT devices often experience large SFO, achieving sufficient timing accuracy to enable consistent CP removal is challenging. Imperfect synchronization can require additional signal conditioning (e.g., filtering), which increases receiver complexity and power requirements, both of which are constraints in low-power A-IoT design.

[0106] Accordingly, alternative CP handling methods are expected to preserve envelope signal integrity and avoid false detections in OFDM-based OOK transmissions.

[0107] As mentioned above, the low complexity of A-IoT receivers can prevent them from accurately identifying and removing the CP at the beginning of each OFDM symbol. To reduce complexity and preserve energy efficiency, it can be preferable for A-IoT devices to treat the entire OFDM symbol including the CP as a continuous time-domain envelope for detection rather than explicitly discarding the CP.

[0108] However, care must be taken to ensure that CP insertion does not introduce false rising or falling edges into the waveform, particularly between adjacent OOK chips. In OFDM-based OOK waveforms that transmit multiple chips per symbol, such as OOK-4 with M > 1, the CP (which replicates the end of the symbol) can inadvertently introduce unintended transitions at the symbol boundary, degrading envelope detection accuracy.

[0109] The OFDM baseband signal is generated as a time-continuous baseband signal for OFDM symbol / , subcarrier spacing configuration μ, and antenna port p, as shown in Equation 1:

[0110]

[0111] wherein is the start time for OFDM symbol / ,

[0112]

[0113] wherein is the size of the resource grid for subcarrier spacing configuration μ, is the number of subcarriers per resource block.

[0114] Here, the subcarrier spacing is:

[0115] Δf = 2 μ x 15 [kHz] Equation 3

[0116] The subcarrier shift term is defined as:

[0117]

[0118] where, is the start of the resource grid for subcarrier spacing configuration μ, is the start of the resource grid for subcarrier spacing configuration μ0, and is the size of the resource grid for subcarrier spacing configuration μ0.

[0119] where the subscript x is set to R2D to indicate the reader-to-device link, and μ0 is the largest μ value in the subcarrier spacing configuration.

[0120] The total OFDM symbol duration, including the CP, is:

[0121]

[0122] For Equations 1-5, μ is the subcarrier spacing configuration, μ0 is the largest subcarrier spacing index across all configurations, is the number of useful samples in the IFFT, is the number of CP samples for symbol l, and T c is the sampling period.

[0123] Thus, based on Equations 1-5, each OFDM symbol has a duration which includes a CP of length In 3GPP NR, the CP is obtained by copying the last samples of the OFDM symbol to the beginning of the OFDM symbol to combat channel impairments. In other words, the OFDM symbol duration includes two segments (the CP which is a copy of the last samples of the OFDM symbol and the samples following the CP).

[0124] Figure 11 The impact of CP insertion on the OOK signal waveform is shown according to an embodiment.

[0125] Referring to Figure 11, showing a simple example where the OFDM symbol carries two OOK chips (i.e., M = 2) representing the bit pattern of "0" and "1" after "0". Before CP insertion, the envelope exhibits a single rising edge at the midpoint. However, after CP insertion, the tail of the CP replica signal, which corresponds to "1", is prepended to the symbol. As a result, a spurious rising edge is introduced at the very beginning of the symbol, which can be misinterpreted by the envelope detector as a valid data transition.

[0126] From the perspective of an A-IoT device utilizing envelope detection, the presence of the CP can result in the detection of a spurious transition within the OFDM symbol. For example, even when transmitting a bit sequence of "0" followed by "1", the envelope detector can interpret the CP as an additional transition, resulting in a detected sequence of "101" due to the spurious edge introduced at the beginning of the symbol. This misjudgment degrades the detection performance and increases the probability of false symbol decisions.

[0127] To address this problem and mitigate the impact of the CP on A-IoT devices, the present disclosure provides systems and methods for handling the CP in OFDM-based OOK waveforms.

[0128] According to embodiments, the first systems and methods introduce a modified CP generation that uses the beginning of the OFDM symbol.

[0129] In some OFDM systems, the CP can be formed by copying the last samples of the OFDM symbol and inserting them at the beginning, preserving the circular convolution property for frequency domain processing. However, in A-IoT systems employing envelope detection, this approach can backfire as it can introduce unintended transitions.

[0130] To eliminate the spurious edges introduced by CP insertion, the CP generation strategy at the transmitter can be modified. Instead of copying the last samples of the additional OFDM symbol, this approach generates the CP by copying the first samples of the first OOK chip within the OFDM symbol. This CP structure preserves the envelope continuity of the signal at the symbol boundary, avoiding the introduction of artificial rising or falling edges between the last chip of OFDM symbol n-1 and the first chip of OFDM symbol n. As a result, the envelope-detected signal becomes free of CP-induced artifacts, allowing the CP to be efficiently ignored at the receiver without degrading the detection performance.

[0131] Thus, for an antenna port p, a subcarrier spacing configuration μ, and an OFDM symbol I in a slot, the time-continuous signal

[0132]

[0133] In this equation, equations 2 to 5 still apply to equation 6, and additionally correspond to the first system and method described herein, where the CP is generated by copying the beginning of the OFDM symbol instead of the end.

[0134] According to embodiments, the second system and method introduce a symbol length adjustment for OOK chips of equal duration.

[0135] The second system and method exploit a controlled adjustment of the symbol structure. In this way, the total duration of the OOK chips within each OFDM symbol is carefully arranged so that all OOK chips, including the first symbol containing the CP, have equal effective length.

[0136] For example, consider the case of an OOK-4 waveform with M > 1. If the CP preceding the first OOK chip has a length of N1 samples, then the first OOK chip can be shortened to N1 samples, while each of the remaining OOK chips is lengthened to N2 samples, so that:

[0137] Although there is a CP at the beginning, by ensuring that all OOK chips occupy the same total duration in the time domain, the receiver interprets the signal as uniformly spaced OOK chips. This way preserves the signal symmetry and avoids the generation of spurious jumps due to sudden changes in the envelope shape. Although this approach reduces the effective bit rate (due to fewer available samples per OFDM symbol), it provides a robust and low-complexity solution for CP handling in envelope detection based A-IoT receivers.

[0138] In some deployments, A-IoT devices can operate in-band with regular 5G NR cellular UEs. In this case, the base station (e.g., gNB) can act as a reader and be responsible for transmitting both regular NR signals and A-IoT signals simultaneously. To support this dual functionality, the reader can be configured to perform two separate baseband signal generation processes, one for cellular NR data and one for A-IoT data, each involving independent IFFT operations and CP insertion.

[0139]

[0140] ​For example, in a topology where the gNB communicates directly with both an A-IoT receiver and an NR UE, the reader can generate an OFDM-based signal for the A-IoT device in parallel with the signal for the NR UE. Each signal can be processed independently using different modulation and waveform generation chains, and then summed before RF transmission. This parallel generation and combination approach supports flexible waveform coexistence and minimizes interference between co-located traffic.

[0141] Figure 12 is a block diagram of a signal generation architecture at a reader configured to support both cellular and A-IoT transmission paths according to an embodiment.

[0142] Referring to Figure 12 , a data source 1201 provides a bitstream to control logic 1202, which determines whether the incoming data corresponds to NR cellular traffic or A-IoT traffic. If the data is identified as cellular traffic, it is passed to modulator 1203 and processed through S / P converter 1204 and subsequent IFFT block 1205. CP insertion module 1206 generates a CP by copying the last N CP samples of an OFDM symbol and appending them at the beginning of the symbol. The resulting signal is then transmitted via RF front end 1207.

[0143] Optionally, if the data is designated for A-IoT transmission by control logic 1202, it is passed to OOK-1 / OOK-4 signal generator 1208. According to one embodiment, CP generator (or insertion) 1209 forms a CP by copying the first N CP samples of the first OOK chip within an OFDM symbol and appending them to the front of the symbol. This ensures that there are no spurious jumps in the envelope, and enables compatibility with low-complexity, envelope-detection A-IoT receivers. Optionally, the length of the OOK chip can also be configured such that the duration of the first OOK chip (including the CP) is equal to the duration of the remaining OOK chips, preserving uniform symbol timing. The A-IoT signal is then merged with the NR signal at a summing point before transmission via RF front end 1207.

[0144] According to another embodiment, rather than restricting the CP to a particular portion of the OOK chip (e.g., only the beginning or the end), a CP can be formed from any selected N CP samples within the first OOK chip in an OFDM symbol.

[0145] For example, in some implementations, the CP can be constructed by copying a region that exhibits the smallest slope or a segment from the middle region of the first OOK chip to suppress unwanted transient behavior at the symbol boundary.

[0146] In another embodiment, the CP can be completely omitted in an OFDM-based OOK transmission. That is, no CP is inserted at the transmitter and the OFDM symbol includes the IFFT output corresponding to the modulated OOK data. This approach can be beneficial in scenarios where the CP provides little or no performance advantage.

[0147] According to another embodiment, additional techniques can be applied to enhance robustness and reduce false edge detection in ASK modulated signals, such as OOK-1 or OOK-4, in an A-IoT system. Specifically, padding chips can be inserted at one or both ends of the OOK signal to reduce the likelihood of unintended jumps during CP insertion. For example, padding chips can be appended after the last OOK chip in a symbol, or inserted at both the beginning and end of the OOK chip sequence. These padding chips can serve to moderate the amplitude jump between adjacent OFDM symbols, effectively mitigating the occurrence of false rising or falling edges at the CP boundary.

[0148] According to another embodiment, for OOK transmissions with M exceeding 12 OOK chips, a refined CP handling approach can be selected to further mitigate envelope detection false images. In particular, the option of inserting padding chips only at the end of the OOK chip sequence within the OFDM symbol can be employed, thereby ensuring that the last two OOK chips out of the M OOK chips at the end of each OFDM symbol are always in the "on" state.

[0149] In another embodiment, a reader-side signal generation for OOK-4 modulation based on DFT-spread OFDM (DFT-s-OFDM) waveform can follow a structured process without requiring specific implementation. First, an OFDM symbol can be defined to contain M OOK chips, where each chip corresponds to a discrete OOK symbol. Each OOK chip can be represented by L time-domain samples, such that a block of M x L samples forms the input of an N' -point DFT operation, where N' = M x L. The output of the N' -point DFT can then be mapped to X frequency-domain subcarriers, where X corresponds to the bandwidth allocated for R2D transmission and satisfies the relationship N' is greater than or equal to X. After this mapping, an N-point inverse discrete Fourier transform (IDFT) can be performed to generate a time-domain OFDM signal for transmission. Additionally, the generation process can include inserting a CP after the IDFT operation to form the final transmitted OFDM symbol. In certain implementations, a standard specification can be required regarding the definition of at least the OFDM symbol structure and the IDFT operation. Further timing details related to CP insertion can also be reflected in the system design to ensure compliance with transmission requirements.

[0150] In another embodiment related to CP processing that does not maintain subcarrier orthogonality, the design of the OFDM symbol can be constrained such that it includes a total duration of the CP that accommodates an integer number of OOK chips. In this case, the CP is not derived by copying the end of the OFDM symbol. Instead, an arbitrary sample or padded sample CP can be inserted to form a well-structured symbol without introducing disruptive jumps. For example, a system can be configured such that 14 OFDM symbols (each including an integer number of OOK chips) fit within a slot duration. This approach aligns with the typical timing structure in 3GPP systems.

[0151] Figure 13 is a flowchart illustrating a method for CP processing and waveform generation for OOK transmission based on OFDM according to an embodiment.

[0152] Referring to Figure 13 , the method can be performed by any network device, such as a network node (e.g., a base station or gNB), a terminal device, a satellite, or any other suitable transmission entity capable of supporting A-IoT communication. The method begins at step 1301, where the network device transmits a bit stream that includes A-IoT data. The bit stream can represent various types of information, including application data, control signaling, or wake-up messages intended for low-power A-IoT devices. In some embodiments, techniques such as error correction coding, line coding, or scrambling can be used to process the bit stream to enhance robustness to wireless impairments.

[0153] At step 1302, the method includes generating a waveform (e.g., OFDM symbol) modulated according to an OOK-1 or OOK-4 modulation scheme. At least a portion of the OOK-1 or OOK-4 generation can be in the frequency domain, and a portion of the generation can be in the time domain (e.g., CP addition). Optionally, the OOK-1 or OOK-4 modulated waveform is multiplexed with a NR signal in the frequency domain prior to the addition of a CP in the time domain. Optionally, when the OOK-1 or OOK-4 modulated waveform includes (or is multiplexed with) a NR signal, the CP is generated by copying an end portion of the OOK-1 or OOK-4 modulated waveform. In OOK-1 modulation, a single bit or chip is transmitted per OFDM symbol, while in OOK-4 modulation, multiple OOK chips are typically embedded within a single OFDM symbol, often through DFT-s-OFDM techniques. The selection between OOK-1 and OOK-4 can depend on system design considerations, such as data throughput requirements, receiver complexity, and energy efficiency goals. In some examples, pulse shaping or spectral shaping operations can optionally be applied prior to the Fourier transform operation to manage peak-to-average power ratio or control spectral occupancy.

[0154] At step 1303, the method includes generating the CP by copying one or more samples of a first OOK chip within the waveform (e.g., OFDM symbol). In contrast to some OFDM systems that generate the CP from the last sample of the OFDM symbol, the present technology generates the CP from a sample associated with the first OOK chip. In certain embodiments, the CP can be generated by copying the starting sample of the first OOK chip, although other portions from the first chip can be used for copying depending on the implementation. The number of samples copied can be selected based on considerations such as an expected maximum channel delay spread, an expected guard interval duration, or system-specific design optimizations. Optionally, if the length of the CP is greater than the length of the first OOK chip in the OOK-1 or OOK-4 modulated waveform, the one or more samples of the first OOK chip are copied multiple times to generate the CP.

[0155] At step 1304, the method includes appending the CP at the beginning of the first OOK chip in the waveform (e.g., OFDM symbol). Appending the CP in this manner helps to prevent abrupt amplitude jumps between consecutive OFDM symbols, thereby improving envelope detection reliability at a receiving A-IoT device. In some embodiments, the timing of the first OOK chip can be adjusted in relation to the CP length to maintain a uniform symbol duration, or alternative padding techniques can be employed to ensure consistent transmission structure across multiple OFDM symbols.

[0156] In step 1305, the method includes transmitting a waveform (e.g., OFDM symbols) with additional CP (Content Processing) over a wireless channel to one or more A-IoT devices. The wireless transmission can occur on licensed or unlicensed spectrum bands and can use low-power transmission schemes compatible with the energy constraints of A-IoT deployments. In various examples, the network devices may sequentially transmit multiple OFDM symbols according to the described CP processing method.

[0157] Figure 14 This is a block diagram of an electronic device in a network environment according to an embodiment.

[0158] Reference Figure 14 In network environment 1400, electronic device 1401 can communicate with electronic device 1402 via a first network 1498 (e.g., a short-range wireless communication network), or with electronic device 1404 or server 1408 via a second network 1499 (e.g., a long-range wireless communication network). Electronic device 1401 can communicate with electronic device 1404 via server 1408. Electronic device 1401 may include processor 1420, memory 1430, input device 1450, sound output device 1455, display device 1460, audio module 1470, sensor module 1476, interface 1477, connection terminal 1478, haptic module 1479, camera module 1480, power management module 1488, battery 1489, communication module 1490, user identification module (SIM) (card) 1496, or antenna module 1497. In one embodiment, at least one of the components (e.g., display device 1460 or camera module 1480) may be omitted from electronic device 1401, or one or more other components may be added to electronic device 1401. Some components may be implemented as a single integrated circuit (IC). For example, sensor module 1476 (e.g., fingerprint sensor, iris sensor, or illuminance sensor) may be embedded in display device 1460 (e.g., display).

[0159] The systems and methods described throughout this disclosure, including CP processing techniques for OFDM-based OOK waveforms, can be derived from... Figure 14 The electronic device 1401 shown is implemented or operates on one or more of the components therein. Specifically, the processor 1420 may be configured to execute instructions stored in memory 1430 to generate OOK-1 or OOK-4 waveforms, perform CP insertion using one or more of the proposed methods, and coordinate the transmission of the obtained signals via communication module 1490 and antenna module 1497. Communication module 1490 may include the RF front-end and baseband components required to implement the transmitter processing chain.

[0160] In embodiments where the electronic device 1401 is used as a reader (e.g., a gNB or other access point), the processor 1420 can also be configured to determine whether a bitstream corresponds to NR cellular or A-IoT traffic and route data to the appropriate waveform generation path. An auxiliary processor 1423 can be used to offload signal processing tasks such as IFFT computation, OOK chip mapping, or CP insertion to improve power efficiency. Hardware acceleration components within the auxiliary processor 1423 or elsewhere in the device can also be used to support real-time waveform generation or envelope shaping logic.

[0161] These components, when programmed or configured as described herein, enable the device to support coexistence of A-IoT and NR signaling by flexibly managing CP generation and OFDM symbol construction, including approaches such as copying the first sample of an OOK chip, balancing OOK chip duration, or omitting the CP entirely. Thus, Figure 14 The illustrated structure provides a suitable hardware platform for implementing the disclosed R2D signal processing techniques.

[0162] The processor 1420 can execute software (e.g., programs 1440) to control at least one other component (e.g., a hardware or software component) of the electronic device 1401 coupled with the processor 1420 and can perform various data processing or computation. The programs 1440 can be configured to include a program for driving a user interface (UI) or a graphical user interface (GUI) related to at least one of the above-described embodiments, and the program can be stored in the non-volatile memory 1434 or loaded in the volatile memory 1432. The programs 1440 can include, e.g., a kernel 1441, a middleware 1443, or an application programming interface (API) 1445, which can be controlled through the middleware 1443 by an application 1447.

[0163] As at least a part of the data processing or computation, the processor 1420 can load a command or data received from another component (e.g., the sensor module 1446 or the communication module 1490) to the volatile memory 1432, process the command or data stored in the volatile memory 1432, and store the resultant data in the non-volatile memory 1434. The processor 1420 can include a main processor 1421 (e.g., a central processing unit (CPU) or an application processor (AP)) and an auxiliary processor 1423 (e.g., a graphics processor (GPU), an image signal processor (ISP), a sensor hub processor, or a communication processor (CP)), which can operate independently of the main processor 1421 or in conjunction with the main processor 1421. Additionally or alternatively, the auxiliary processor 1423 can be adapted to consume less power than the main processor 1421 or to perform a specific function. The auxiliary processor 1423 can be implemented as separate from or as part of the main processor 1421.

[0164] The auxiliary processor 1423, instead of the main processor 1421, can control at least some of the functions or states related to at least one component (e.g., the display device 1460, the sensor module 1476, or the communication module 1490) of the electronic device 1401 while the main processor 1421 is in an inactive (e.g., sleep) state, or together with the main processor 1421 when the main processor 1421 is in an active state (e.g., executing an application), and the auxiliary processor 1423 (e.g., an image signal processor or a communication processor) can be implemented as a part of another component functionally related to the auxiliary processor 1423 (e.g., the camera module 1480 or the communication module 1490).

[0165] The memory 1430 can store various data used by at least one component (e.g., the processor 1420 or the sensor module 1476) of the electronic device 1401. The various data can include, for example, software (e.g., the program 1440) and input data or output data for a command related thereto. The memory 1430 can include the volatile memory 1432 or the non-volatile memory 1434. The non-volatile memory 1434 can include the internal memory 1436 and / or the external memory 1438.

[0166] The program 1440 can be stored in the memory 1430 as software, and can include, for example, an operating system (OS) 1442, middleware 1444, or an application 1446.

[0167] The input device 1450 can receive a command or data, which is used for another component (e.g., the processor 1420) of the electronic device 1401, from the outside (e.g., a user) of the electronic device 1401. The input device 1450 can include, for example, a microphone, a mouse, or a keyboard.

[0168] The sound output device 1455 can output sound signals to the outside of the electronic device 1401. The sound output device 1455 can include, for example, a speaker or a receiver. The speaker can be used for general purposes, such as playing multimedia or recording, and the receiver can be used for receiving an incoming call. The receiver can be implemented as part of the speaker or a separate component from the speaker.

[0169] The display device 1460 can visually provide information to the outside (e.g., a user) of the electronic device 1401. The display device 1460 can include, for example, a display, a hologram device, or a projector, and a control circuit for controlling a corresponding one of the display, the hologram device, and the projector. The display device 1460 can include a touch circuit adapted to detect a touch or a sensor circuit (e.g., a pressure sensor) adapted to measure the intensity of force by a touch.

[0170] The audio module 1470 can convert a sound into an electrical signal and vice versa. The audio module 1470 can obtain the sound via the input device 1450 or output the sound via the sound output device 1455 or a headphone of an external electronic device 1402 directly (e.g., wiredly) or wirelessly coupled with the electronic device 1401.

[0171] The sensor module 1476 can detect an operational state (e.g., power or temperature) of the electronic device 1401 or an environmental state (e.g., a state of a user) external to the electronic device 1401, and then generate an electrical signal or data value corresponding to the detected state. The sensor module 1476 can include, for example, a gesture sensor, a gyro sensor, an atmospheric pressure sensor, a magnetic sensor, an acceleration sensor, a grip sensor, a proximity sensor, a color sensor, an infrared (IR) sensor, a biometric sensor, a temperature sensor, a humidity sensor, or an illuminance sensor.

[0172] The interface 1477 can support one or more designated protocols to be used for the electronic device 1401 to be coupled with the external electronic device 1402 directly (e.g., wiredly) or wirelessly. The interface 1477 can include, for example, a high definition multimedia interface (HDMI), a universal serial bus (USB) interface, a secure digital (SD) card interface, or an audio interface.

[0173] The connecting terminal 1478 can include a connector that can be physically connected to the external electronic device 1402, via which the electronic device 1401 can receive data, from or supply data to the external electronic device 1402. The connecting terminal 1478 can include, for example, an HDMI connector, a USB connector, a SD card connector, or an audio connector (e.g., a headphone connector).

[0174] The haptic module 1479 can convert an electrical signal into a mechanical stimulus (e.g., a vibration or a movement) that can be felt by a user or an electrical stimulus that can be felt by a user via a tactile sensation or a kinesthetic sensation. The haptic module 1479 can include, for example, a motor, a piezoelectric element, or an electrical stimulator.

[0175] The camera module 1480 can capture still images or moving images. The camera module 1480 can include one or more lenses, image sensors, image signal processors, or flashes. The power management module 1488 can manage power supplied to the electronic device 1401. The power management module 1488 can be implemented as at least part of, for example, a power management integrated circuit (PMIC).

[0176] The battery 1489 can supply power to at least one component of the electronic device 1401. The battery 1489 can include, for example, a primary cell which is not rechargeable, a secondary cell which is rechargeable, or a fuel cell.

[0177] The communication module 1490 can support establishing a direct (e.g., wired) communication channel or a wireless communication channel between the electronic device 1401 and an external electronic device (e.g., the electronic device 1402, the electronic device 1404, or the server 1408) and performing communication between the electronic devices 1401, 1402, 1404, 1408 via the established communication channel. The communication module 1490 can include one or more communication processors that are operable independently from the processor 1420 (e.g., an AP) and support direct (e.g., wired) communication or wireless communication. The communication module 1490 can include a wireless communication module 1492 (e.g., a cellular communication module, a short-range wireless communication module, or a global navigation satellite system (GNSS) communication module) or a wired communication module 1494 (e.g., a local area network (LAN) communication module or a power line communication (PLC) module). A corresponding one of these communication modules can communicate with the external electronic device via the first network 1498 (e.g., a short-range communication network, such as Bluetooth, wireless-fidelity (Wi-Fi) direct, or infrared data association (IrDA)) or the second network 1499 (e.g., a long-range communication network, such as a cellular network, the Internet, or a computer network (e.g., LAN or wide area network (WAN)). These various types of communication modules can be implemented as a single component (e.g., a single IC) or can be implemented as separate components (e.g., separate ICs) from each other. The wireless communication module 1492 can identify and authenticate the electronic device 1401 in a communication network, such as the first network 1498 or the second network 1499, using subscriber information (e.g., an international mobile subscriber identity (IMSI)) stored in the subscriber identification module 1496. TM

[0178] ​The antenna module 1497 can transmit or receive a signal or power to or from an external electronic device (e.g., an external electronic device) of the electronic device 1401. The antenna module 1497 can include one or more antennas, and can therefore, for example, select at least one antenna appropriate for a communication scheme used in a communication network, such as the first network 1498 or the second network 1499, by the communication module 1490 (e.g., the wireless communication module 1492). Then, signals or power can be transmitted or received between the communication module 1490 and the external electronic device via the selected at least one antenna.

[0179] Commands or data can be transmitted or received between the electronic device 1401 and the external electronic device 1404 via the server 1408 connected with the second network 1499. Each of the electronic device 1402 and the electronic device 1404 can be a device of a same type as or different from the electronic device 1401. All or some of the operations performed at the electronic device 1401 can be performed at one or more of the external electronic devices 1402, 1404, or server 1408. For example, if the electronic device 1401 is to perform a function or a service automatically, or in response to a request from a user or another device, the electronic device 1401, instead of, or in addition to, executing the function or the service, can request at least a part of the function or the service to be performed by one or more of the external electronic deviceses. The one or more external electronic devices receiving the request can perform the requested at least part of the function or the service, or an additional function or an additional service related to the request, and transfer a result of the performance to the electronic device 1401. The electronic device 1401 can provide the result, with or without further processing, as at least a part of a reply to the request. To that end, a cloud computing, distributed computing, or client-server computing technology can be used, for example.

[0180] Figure 15 is a system including a UE and a base station gNB in communication with each other according to an embodiment.

[0181] Referring to Figure 15 The UE can include a radio 1515 and processing circuitry (or means for processing) 1520, which can perform various methods disclosed herein. For example, the processing circuitry 1520 can receive a transmission from a network node (gNB) 1510 via the radio 1515, and the processing circuitry 1520 can transmit a signal to the gNB 1510 via the radio 1515.

[0182] Embodiments of the subject matter and operations described in this specification can be implemented in digital electronic circuitry, or in computer software, firmware, or hardware, including the structures disclosed in this specification and their structural equivalents, or in combinations of one or more of them. Embodiments of the subject matter described in this specification can be implemented as one or more computer programs, i.e., one or more modules of computer program instructions, encoded on computer storage medium for execution by, or to control the operation of, data processing apparatus. Additionally or alternatively, program instructions can be encoded on an artificially generated propagated signal, e.g., a machine-generated electrical, optical, or electromagnetic signal, that is generated to encode information for transmission to suitable receiver apparatus for execution by a data processing apparatus. The computer storage medium can be a computer-readable storage device, a computer-readable storage substrate, a random or serial access memory array or device, or a combination of computer-readable storage devices, computer-readable storage substrates, random or serial access memory arrays or devices, or the like, whether volatile or non-volatile memory or memory or storage that is tangible and that is included in a computer system's or apparatus's normally- used working environment. Furthermore, a computer storage medium or means that is not a propagated signal can be a source or destination of computer program instructions encoded in an artificially generated propagated signal, e.g., a machine-generated electrical, optical, or electromagnetic signal that is generated to encode information for transmission to suitable receiver apparatus for execution by a data processing apparatus. The computer storage medium can also be, or be included in, one or more separate physical components or media (e.g., multiple CDs, disks, or other storage devices). Additionally, the operations described in this specification can be implemented as operations performed by a data processing apparatus on data stored on one or more computer-readable storage devices or received from other sources.

[0183] Although this specification can contain many implementation details, these should not be interpreted to limit the scope of any claims— regardless of whether they are presented in this background section, the summary of the disclosure section, or elsewhere in this specification. Regardless of their presence in this specification or not, the subject matter described in this specification (including any claims) can be implemented in hardware, software, firmware, or in combinations of both hardware and software, including one or more computer programs that are encoded on computer storage medium for execution by, or to control the operation of, data processing apparatus. Additionally or alternatively, a program instruction can be encoded on an artificially generated propagated signal, e.g., a machine-generated electrical, optical, or electromagnetic signal that is generated to encode information for transmission to suitable receiver apparatus for execution by a data processing apparatus. The computer storage medium can be a computer-readable storage device, a computer-readable storage substrate, a random or serial access memory array or device, or a combination of computer-readable storage devices, computer-readable storage substrates, random or serial access memory arrays or devices, or the like, whether volatile or non-volatile memory or memory or storage that is tangible and that is included in a computer system's or apparatus's normally- used working environment. Furthermore, the operations described in this specification can be implemented as operations performed by a data processing apparatus on data stored on one or more computer-readable storage devices or received from other sources.

[0184] Similarly, while operations are depicted in the drawings in a particular order, this should not be understood as requiring such order nor limiting all illustrations to that order, unless the schedule requires it. One of ordinary skill in the art will recognize that the operations of the disclosed examples can be performed in a manner different than illustrated without departing from the scope of the present disclosure. Moreover, acts associated with a given example can be modified in number and / or order without departing from such example. Additionally, the various systems components can be combined in a single software product or packaged into multiple software products without departing from the scope of the disclosure.

[0185] Accordingly, particular embodiments of the subject matter have been described herein. Other embodiments are within the scope of the following claims. In some cases, actions recited in the claims can be performed in a different order and still achieve desirable results. Additionally, the processes depicted in the accompanying figures do not necessarily require the particular order shown, or sequential order, to achieve the desired results. In certain implementations, multitasking and parallel processing can be advantageous.

[0186] As will be recognized by the skilled person, the innovative concepts described herein can be modified and adapted in a wide range of applications. The scope of the claimed subject matter is therefore not to be limited to any of the particular exemplary teachings discussed above, but is defined by the claims.

Claims

1. A method for transmitting data in a wireless communication network, the method comprising: Receive bit streams, including A-IoT data, from network nodes; Generate waveforms modulated by on / off key control OOK-1 or OOK-4; The cyclic prefix CP is generated by copying one or more samples of the first OOK chip in the waveform; The CP is appended at the beginning of the first OOK chip in the waveform; as well as The waveform with the additional CP is transmitted to one or more A-IoT devices over a wireless channel.

2. The method according to claim 1, wherein, The waveforms modulated by OOK-1 or OOK-4 are generated using Discrete Fourier Transform Extended Orthogonal Frequency Division Multiplexing (DFT-s-OFDM) waveforms.

3. The method according to claim 1, wherein, The waveform modulated by OOK-1 or OOK-4 is multiplexed with the new radio NR signal in the frequency domain before the CP is added in the time domain.

4. The method according to claim 3, wherein, When the waveform is multiplexed with the NR signal, the CP is generated by copying the end portion of the waveform.

5. The method according to claim 1, wherein, The CP is achieved by copying the first N bits of the first OOK chip in the waveform. c It is generated from p samples, where N c p is the CP length configured by the network node.

6. The method according to claim 1, wherein, The CP is achieved by copying any N from the first OOK chip in the waveform. c It is generated from p samples, where N c p is the CP length configured by the network node.

7. The method according to claim 1, wherein, If the length of the CP is greater than the length of the first OOK chip in the waveform, then one or more samples of the first OOK chip are copied multiple times to generate the CP.

8. The method according to claim 1, further comprising: Generate a set of OOK chips such that the duration of the CP and the first OOK chip is equal to the duration of each of the remaining OOK chips in the waveform that does not contain the CP.

9. The method according to claim 1, wherein, The waveform includes M OOK chips, and the duration of the waveform including the CP is configured to be an integer multiple of the duration of the OOK chips.

10. The method according to claim 1, further comprising: Insert one or more padding OOK chips at the end of the waveform.

11. The method according to claim 10, wherein, One or more filler OOK chips are inserted immediately after the last OOK chip in the waveform.

12. The method according to claim 1, wherein, The step of transmitting a bit stream including environmental Internet of Things (A-IoT) data includes transmitting 14 orthogonal frequency division multiplexing (OFDM) symbols within a time slot.

13. A system for transmitting data in a wireless communication network, comprising: RF front end; as well as The processor is configured as follows: Receive bit streams, including A-IoT data, from network nodes; Generate waveforms modulated by on / off key control OOK-1 or OOK-4; The cyclic prefix CP is generated by copying one or more samples of the first OOK chip in the waveform; The CP is appended at the beginning of the first OOK chip in the waveform; and The RF front end transmits the waveform with the additional CP to one or more A-IoT devices.

14. The system according to claim 13, wherein, The waveforms modulated by OOK-1 or OOK-4 are generated using Discrete Fourier Transform Extended Orthogonal Frequency Division Multiplexing (DFT-s-OFDM) waveforms.

15. The system according to claim 13, wherein, The waveform modulated by OOK-1 or OOK-4 is multiplexed with the new radio NR signal in the frequency domain before the CP is added in the time domain.

16. The system according to claim 15, wherein, The processor is also configured to generate the CP by copying the end portion of the waveform when the waveform is multiplexed with the NR signal.

17. The system according to claim 13, wherein, The processor is also configured to: copy the first N bits of the first OOK chip in the waveform. c p samples are used to generate the CP, where N c p is the CP length configured by the network node.

18. The system according to claim 13, wherein, The processor is also configured to: copy any N of the first OOK chip in the waveform. c p samples are used to generate the CP, where N c p is the CP length configured by the network node.

19. The system according to claim 13, wherein, The processor is further configured to: if the length of the CP is greater than the length of the first OOK chip, then copy the one or more samples of the first OOK chip in the waveform multiple times to generate the CP.

20. The system according to claim 13, wherein, The processor is further configured to generate a set of OOK chips such that the duration of the CP and the first OOK chip is equal to the duration of each of the remaining OOK chips in the waveform that does not contain the CP.

21. The system according to claim 13, wherein, The waveform includes M OOK chips, and, The duration of the waveform including the CP is configured to be an integer multiple of the duration of the OOK chip.

22. The system according to claim 13, wherein, The processor is also configured to insert one or more padding OOK chips at the end of the waveform.

23. The system according to claim 22, wherein, The processor is also configured to insert one or more filler chips immediately after the last OOK chip in the waveform.

24. The system according to claim 13, wherein, The processor is also configured to generate 14 orthogonal frequency division multiplexing (OFDM) symbols per time slot.

25. A non-transitory computer-readable medium storing instructions that, when executed by a processor, cause the processor to perform the following operations: Receive bit streams, including A-IoT data, from network nodes; Generate waveforms modulated by on / off key control OOK-1 or OOK-4; The cyclic prefix CP is generated by copying one or more samples of the first OOK chip in the waveform; The CP is appended at the beginning of the first OOK chip in the waveform; and This enables the waveform with the additional CP to be transmitted over a wireless channel to one or more A-IoT devices.

26. The non-transitory computer-readable medium according to claim 25, wherein, The instruction also causes the processor to insert one or more padding OOK chips immediately after the OOK chip of the waveform.

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