Synchronization in Ambient IoT Environments

Abstract

This invention provides methods, devices, and products for synchronization in ambient IoT (IoT) environments. [Solution] The method according to the present invention comprises a reader generating a timing acquisition signal for an AIOT device, the timing acquisition signal comprising a preamble having a start instruction section and a clock acquisition section. Generating the timing acquisition signal comprises forming a start instruction section having a pattern that identifies the start of a transmission from the reader to the device, and forming a clock acquisition section that includes a signal corresponding to a timing parameter associated with a subsequent transmission. The reader then transmits the timing acquisition signal to the AIOT device to enable timing synchronization.

Description

Technical Field

[0001] Reference to Related Applications This application claims priority based on U.S. Provisional Application No. 63 / 729,287, filed on December 6, 2024, the disclosure of which is hereby incorporated by reference in its entirety.

[0002] The present invention generally relates to data communication. More specifically, the subject matter disclosed herein relates to improvements in synchronization in an Ambient Internet-of-Things (AIoT) environment.

Background Art

[0003] AIoT systems extend conventional wireless communication frameworks and support low-power devices and energy-harvesting devices. IoT (Internet of Things) refers to a network architecture in which interconnected devices exchange data via wireless or wired connections, enabling distributed sensing, distributed monitoring, and distributed control. AIoT is an evolutionary form of this concept, where devices operate with extremely low power consumption, often harvesting energy from wireless frequency sources in the environment and communicating using reflected signals or weak transmission signals instead of continuous active transmissions. Examples of AIoT devices include battery-free environmental sensors for monitoring temperature, humidity, and air quality, asset-tracking tags used in logistics and supply chain management, identification labels or tags embedded in retail packaging, smart home sensors that detect movement and light, structural health monitoring (SHM) sensors incorporated into buildings and infrastructure, wearable or implantable biomedical sensors, and agricultural sensors for measuring soil moisture and crop conditions.

[0004] In an AIOT environment, a reader transmits downlink signals that provide energy and information to AIOT devices, and AIOT devices communicate through reflected or active transmission. These systems rely on precise timing and frequency references so that devices can correctly interpret the control and data signals transmitted from the reader. Conventional radio synchronization technologies used in cellular communications and Wi-Fi® networks assume the presence of a stable oscillator, a continuous power supply, and sufficient processing resources to track complex preambles. Ambient IoT devices often lack these capabilities because they operate intermittently and rely on harvested energy.

[0005] Readers communicating with energy harvesting devices must transmit synchronization information within very short signaling intervals and under fluctuating energy conditions. Existing downlink signaling formats developed for active wireless devices typically include long training sequences or high-density reference signals, which require continuous power supply and high sampling accuracy. These formats increase decoding complexity and reduce device uptime. As ambient IoT networks expand and support a wider variety of device types and deployment scenarios, the limitations of traditional synchronization procedures restrict network scalability and reliable access to devices. [Overview of the project]

[0006] To overcome these problems, methods, apparatus, and products for performing synchronization in an AIOT environment are disclosed herein. According to the various embodiments described herein, synchronization in an AIOT environment enables a reader to generate a timing acquisition signal for one AIOT device (or any number of AIOT devices in the environment). The timing acquisition signal includes a preamble having a start-indicator part and a clock-acquisition part. The clock-acquisition part includes signals corresponding to the timing parameters associated with the clock-acquisition part and subsequent reader-to-device transmissions. The reader then transmits the timing acquisition signal to the AIOT device. When the AIOT device receives the timing acquisition signal, it detects a pattern in the start-indicator part to determine the start of a reader-to-device transmission, and further uses the signals in the clock-acquisition part to derive timing parameters and synchronize the device clock to the reader's transmission timing.

[0007] The methods described herein represent an improvement over prior art, enabling reliable time alignment for low-power AIOT devices without requiring continuous monitoring, high-complexity processing, or dedicated reference hardware. By using a preamble including an initiation and clock acquisition section, the AIOT device can detect the start of transmission from the reader to the device with minimal signal energy and directly determine timing parameters from the received waveform. This structure reduces synchronization latency, improves timing accuracy, and lowers the energy required for clock recovery. The techniques described herein enable the reader to maintain synchronization with multiple devices operating under different power and frequency conditions, thereby supporting large-scale AIOT deployments. These improvements enhance communication stability, reduce transmission errors, and extend the operating life of devices, even in environments where conventional synchronization performance is limited by energy harvesting or intermittent connections. [Means for solving the problem]

[0008] A method for synchronization in AIOT according to one aspect of the present invention includes a reader generating a timing acquisition signal for an AIOT device. The timing acquisition signal includes a preamble having a start instruction and a clock acquisition. The synchronization further includes the reader forming the start instruction, the start instruction having a pattern that identifies the start of a transmission from the reader to the device. In various embodiments, the synchronization in an AIOT environment further includes the reader forming the clock acquisition. The clock acquisition includes a signal corresponding to the clock acquisition and timing parameters associated with a subsequent transmission from the reader to the device. The synchronization in an AIOT environment further includes the reader transmitting the timing acquisition signal to the AIOT device in order to enable timing synchronization. After receiving the timing acquisition signal, the AIOT device detects the pattern in the start instruction to determine the start of a transmission from the reader to the device. The AIOT device then uses the signal in the clock acquisition to derive the timing parameters, aligns its device clock with the reader's transmission timing, and establishes synchronization for subsequent communication.

[0009] A device configured for synchronization in an AIOT environment according to one aspect of the present invention comprises at least one processing device and a memory coupled to the processing device, the memory storing instructions that, when executed by the processing device, cause the device to generate a timing acquisition signal for an AIOT device. The timing acquisition signal includes a preamble having a start instruction and a clock acquisition. The processing device forms the start instruction, which has a pattern that identifies the start of a reader-to-device transmission. The processing device further forms the clock acquisition, which includes a signal corresponding to the clock acquisition and timing parameters associated with subsequent reader-to-device transmissions. The processing device transmits the timing acquisition signal to the AIOT device to enable timing synchronization.

[0010] A computer program product configured for synchronization in an AIOT environment according to one aspect of the present invention comprises a non-temporary computer-readable medium that, when executed by one or more processing devices, stores instructions causing the one or more processing devices to generate a timing acquisition signal for an AIOT device. The timing acquisition signal includes a preamble having a start instruction section and a clock acquisition section. The one or more processing devices form the start instruction section, which has a pattern that identifies the start of a reader-to-device transmission. The one or more processing devices further form the clock acquisition section, which includes signals corresponding to the clock acquisition section and timing parameters associated with subsequent reader-to-device transmissions. The one or more processing devices transmit the timing acquisition signal to the AIOT device to enable timing synchronization. [Brief explanation of the drawing]

[0011] [Figure 1] This figure shows an example of an AIOT environment configured for synchronization according to an embodiment of the present invention. [Figure 2] This block diagram shows an example of a first type of AIOT device configured for low-power operation and synchronization according to embodiments of the present invention. [Figure 3] This block diagram shows an example of a second type of AIOT device including an active transmit chain and an RF envelope detector receiver according to an embodiment of the present invention. [Figure 4] This figure shows an example of a timing acquisition signal according to an embodiment of the present invention. [Figure 5A] This is an exemplary exchange timing diagram in which a reader transmits a timing acquisition signal according to an embodiment of the present invention. [Figure 5B] This is an exemplary exchange timing diagram according to an embodiment of the present invention, in which the reader sends a paging message followed by a timing acquisition signal. [Figure 6A] This figure shows an example of a signal useful for frequency synchronization according to an embodiment of the present invention. [Figure 6B] This figure shows an example of an AIOT frequency synchronization signal according to an embodiment of the present invention. [Figure 7A] This timing diagram shows an example of the exchange operation for frequency synchronization according to an embodiment of the present invention. [Figure 7B] This timing diagram shows another example of the exchange operation for frequency synchronization according to an embodiment of the present invention. [Figure 8] This flowchart shows an example of a method for generating and transmitting a timing acquisition signal according to an embodiment of the present invention. [Figure 9] A flowchart shows an example of another method for synchronization according to embodiments of the present invention. [Figure 10] This flowchart shows an example of a frequency synchronization method according to an embodiment of the present invention. [Figure 11] This is a block diagram of an electronic device in a network environment according to one embodiment. [Modes for carrying out the invention]

[0012] Many specific details are described in order to provide a complete understanding of the present invention. However, those skilled in the art will understand that the disclosed embodiments can be carried out without these specific details. In other examples, well-known methods, procedures, components, and circuits are not described in detail so as not to obscure the subject matter disclosed herein.

[0013] Throughout this specification, the phrase "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in relation to that embodiment is included in at least one embodiment disclosed herein. Therefore, while the expressions "in one embodiment," "in an embodiment," or "according to one embodiment" (or other expressions of similar importance) appear in various places throughout this specification, they do not necessarily all refer to the same embodiment. Furthermore, a particular feature, structure, or characteristic can be combined in any suitable way in one or more embodiments. In this regard, the term "exemplary" as used herein means "serving as an example, illustration, or descriptive example." Embodiments described as "exemplary" herein are not necessarily construed as being preferable or advantageous to other embodiments. Furthermore, a particular feature, structure, or characteristic can be combined in any suitable way in one or more embodiments. Also, depending on the context of the discussion herein, singular terms may include their corresponding plural forms, and plural terms may include their corresponding singular forms.Similarly, hyphenated terms (e.g., "two-dimensional," "pre-determined," "pixel-specific") may be used interchangeably with their corresponding non-hyphenated terms (e.g., "two-dimensional," "predetermined," "pixel-specific"), and capitalized spellings (e.g., "counter clock," "row select," "pixout") may be used interchangeably with their corresponding non-capsulated spellings (e.g., "counter clock," "row select," "pixout"). Such occasional, interchangeable usages are not considered contradictory.

[0014] Furthermore, depending on the context of the discussion in this specification, singular terms may include their corresponding plural forms, and plural terms may include their corresponding singular forms. Additionally, it should be noted that the various figures (including component diagrams) shown and discussed in this specification are for illustrative purposes only and are not drawn to scale. For example, the dimensions of some elements may be exaggerated relative to others for clarity. Furthermore, where appropriate, reference numbers are repeated between figures to indicate corresponding and / or similar elements.

[0015] The terms used in this specification are for the purpose of describing some exemplary embodiments only and are not intended to limit the present invention. In this specification, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprises" and / or "comprising", when used in this specification, specify the presence of the 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.

[0016] When an element or layer is referred to as being "on" another element or layer, or "connected to" or "coupled to" another element or layer, it will be understood that the element or layer can be directly on the other element or layer, or connected to or coupled to the other element or layer, or there may be intervening elements or layers. 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. The same numerals refer to the same elements throughout. As used in this specification, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0017] As used herein, terms such as "first", "second", etc. are used as labels for the nouns preceding them and do not imply any type of order (e.g., spatial, temporal, logical, etc.) unless explicitly defined as such. Further, the same reference numerals may be used throughout two or more figures to refer to components, elements, blocks, circuits, units, or modules having the same or similar functions. However, such usage is for the sole purpose of simplifying the description and facilitating the discussion, and does not mean that the structure or architecture details of such components or units are the same across all embodiments, or that such commonly referred-to components / modules are the only way to implement some of the exemplary embodiments disclosed herein.

[0018] Unless otherwise defined, all terms (including technical and scientific terms) used herein shall have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Further, terms defined as in a commonly used dictionary shall be interpreted as having a meaning that coincides with the meaning in the context of the relevant art, and shall not be interpreted in an idealized or overly formal sense unless explicitly so defined herein.

[0019] As used herein, the term “module” means any combination of software, firmware, and / or hardware configured to provide the functions described herein in relation to the module. For example, software may be embodied as a software package, code, and / or instruction set, or instructions, and the term “hardware” as used in any implementation described herein may include, for example, assemblies, hardwired circuits, programmable circuits, state machine circuits, and / or firmware that stores instructions executed by programmable circuits, either alone or in any combination. Modules may be embodied collectively or individually as circuits that form part of a larger system, such as, but not limited to, integrated circuits (ICs), system-on-a-chip (SoCs), and assemblies.

[0020] To further explain, Figure 1 shows an example of an AIOT environment configured for synchronization according to various embodiments of the present invention. Low-power devices and energy harvesting devices in an AIOT environment rely on intermittent energy sources and therefore cannot maintain a continuous timing or frequency reference. As mentioned above, conventional synchronization procedures developed for active-powered wireless systems typically use complex preambles, long training sequences, or frequent reference signals to maintain alignment between the transmitter and receiver. These techniques consume a lot of power and processing resources, making them difficult to implement efficiently in AIOT devices. If an efficient synchronization signal is not provided, the AIOT device may not be able to correctly detect the start of transmission, may misinterpret control and data information, may lose alignment with the leader, and may reduce the reliability of the overall communication.

[0021] The exemplary environment 100 shown in Figure 1 comprises a leader 102 and a plurality of devices, including devices 104, 106, and 108. The leader 102 transmits one or more signals to devices 104, 106, and 108 for synchronization, control, or data communication. Each device 104, 106, and 108 receives a transmission from the leader 102 and communicates with the leader 102 using either backscatter transmission or active transmission, depending on the device configuration and available energy.

[0022] As used herein, “Leader” refers to an entity that transmits downlink signals enabling device activation, synchronization, and communication. Leaders may be integrated with or co-located with existing 5G base stations (gNBs) or operate as standalone transmitters performing functions such as energy supply, timing acquisition, frequency synchronization, and data transfer to AIOT devices. Examples of leader devices include cellular base stations, access points, gateways, or other radio transmitters capable of supporting AIOT signal transmission in the Leader-to-Device (R2D) channel.

[0023] In this specification, the term “device” used to refer to an object that receives transmissions from the “reader” refers to a low-power node or energy harvesting node that communicates with the reader using ambient or reflected signals. Examples of devices include environmental sensors, asset tracking tags, identification labels, structural monitors, or biomedical monitors that operate without a continuous power supply. Different device categories exhibit different capabilities in various respects. Such device categories are referred to herein as Device 1, Device 2A, and Device 2B. Those skilled in the art will understand that these are merely examples of device categories or types, and that other device types may exist and can also be fully integrated into the AIOT environment for synchronization as described herein. A device configured as Device 1 type uses only backscatter communication for communication and operates entirely on acquired energy. A device configured as Device 2A type has limited active transmission capability and operates on a carrier signal received as a frequency reference. A device configured as Device 2B type has an internal oscillator that generates a carrier frequency and requires additional synchronization with the reader to maintain frequency matching. These different device types work together within the AIOT environment 100 to achieve efficient communication through low-power synchronization and signaling procedures.

[0024] In the exemplary AIOT environment 100 shown in Figure 1, communication between the reader 102 and devices 104, 106, and 108 occurs through reader-to-device (R2D) transmission and device-to-reader (D2R) transmission. During R2D transmission, the reader 102 generates and transmits a downlink signal containing energy, control, or data information. The downlink signal provides startup energy to one or more devices and enables the transfer of information necessary for device operation. The reader 102 transmits the signal using on-off keying, orthogonal frequency division multiplexing, or other modulation schemes suitable for low-power operation. Depending on the system configuration and device addressing, the R2D transmission may be broadcast to multiple devices or transmitted to a specific device within the AIOT environment 100.

[0025] Following R2D transmission, D2R transmission occurs when one or more devices 104, 106, or 108 respond to the leader 102. D2R transmission is performed by backscatter communication, in which the device modulates the reflection of the leader signal to encode information, or by active uplink transmission, in which the device generates a low-power carrier using energy harvested from the leader signal. D2R transmission carries acknowledgments, control information, or sensing data. In some embodiments, the leader 102 uses timing parameters and resource allocation parameters included in the R2D signal to coordinate multiple D2R transmissions from different devices, enabling scalable and efficient data exchange in the AIOT environment 100.

[0026] In the example in Figure 1, the leader 102 forms a start-indicator part such that the pattern consists of an ON-OFF-ON-OFF sequence. The start-indicator part contains a symbol sequence different from the symbol sequence used for data transmission. In some embodiments, Manchester coding is used to encode the data for R2D transmission. In Manchester coding, each data bit is represented by a two-level transition, where logical "1" is represented by a high-to-low transition and logical "0" is represented by a low-to-high transition. This provides both data and clock information within the same signal. When Manchester coding is used for data, the possible symbol sequences are "10" or "01". If the AIOT device detects a sequence containing a symbol pattern other than these two types, such a sequence can be identified as a start-indicator part.

[0027] On / Off Keying (OOK) is also used to represent symbols that indicate the presence of a pulse (bit "1") and the absence of a pulse (bit "0"). For example, the start instruction in the AIOT transmission preamble employs one of the following sequences: "11 11 11 00 00 00" represented by a 12-bit OOK symbol consisting of one pulse per symbol, "00 00 00 11 11 11" represented by a 12-bit OOK symbol, "11 00 11 10 10" represented by a 10-bit OOK symbol, "01 01 11 00 11" represented by a 10-bit OOK symbol, "00 11 10 01 01" represented by a 10-bit OOK symbol, or "11 01 11 00 10 1" represented by an 11-bit OOK symbol. The start instruction can also be implemented as a high / low voltage signal with an ON-OFF pattern repeated twice. In this case, the first ON-OFF period is used for automatic gain control training, and the second ON-OFF period is used for detecting the start instruction. Automatic gain control is a signal processing technique that dynamically adjusts the amplification level of the received signal to maintain a constant amplitude regardless of fluctuations in signal strength. The sequence used for the start instruction is fixed by the standard or pre-configured by the reader. If the start instruction sequence is pre-configured, the reader associates a sequence identifier with each start instruction sequence and notifies the AIOT device of this identifier via R2D transmission, including a paging message.

[0028] A paging message is a communication sent by a reader to one or more AIOT devices to notify them of upcoming transmissions and to convey configuration information necessary for subsequent communications. The paging message includes identifiers, control parameters, or scheduling information that the devices use to prepare for receiving data or synchronization signals. In some embodiments, the paging message further includes information identifying the sequence used in the initiation section of upcoming timing acquisition signals. Upon receiving a paging message, the AIOT device decodes the information and determines the initiation sequence to be used by the reader. The device saves or updates the corresponding sequence configuration and transitions to a state of monitoring the specific pattern identified in the paging message. This allows the device to detect the start of a "reader-to-device transmission" while minimizing processing load and power consumption.

[0029] As described above, the reader 102 also forms the clock-acquisition part of the preamble. An exemplary clock-acquisition part of the preamble is used for clock correction in an AIOT device or reader. The clock-acquisition part is used to determine the duration of the on-off keying (OOK) chip associated with subsequent Physical Reader-to-Device Channel (PRDCH) transmission. A PRDCH refers to a downlink communication channel through which the reader transmits energy, control information, and data information to one or more AIOT devices. In this invention, a PRDCH refers to either the physical channel itself, the data transmitted on the physical channel, or the data transmitted according to the PRDCH signaling protocol. Orthogonal frequency division multiplexing (OFDM) is a multicarrier modulation technique that improves spectral efficiency and reduces intersymbol interference by simultaneously transmitting multiple subcarriers, each subcarrier carrying part of the data stream. An on-off keying (OOK) chip refers to a discrete time interval representing the presence or absence of a transmission pulse, each corresponding to a binary 1 or binary 0. The clock acquisition unit is configured to transmit a chip duration parameter, represented as M, by encoding the number of rising or falling edges in the signal. For example, if the number of rising or falling edges is 2, the M value is 1. If the number of edges is 4, the M value is 2; if the number of edges is 6, the M value is 6; and if the number of edges is 8, the M value is 8. Furthermore, if the number of edges is between 24 and 26, the M value is 12; if the number of edges is between 32 and 34, the M value is 16; if the number of edges is between 48 and 52, the M value is 24; and if the number of edges is between 64 and 70, the M value is 32.

[0030] When a receiving device receives a timing acquisition signal that includes a clock acquisition unit, the device analyzes the rising and falling edge sequences to determine an M value representing the number of OOK chips per OFDM symbol. Based on the detected number of edges, the device identifies the corresponding M value and uses this information to set the duration of each OOK chip in subsequent communication with the reader. This configuration allows the device to match its device clock to the symbol duration and chip rate used by the reader in subsequent PRDCH transmissions. By matching the timing parameters to the values ​​instructed by the reader, the device can accurately sample and decode the data transmitted in the downlink signal. This makes it possible to improve timing matching and communication reliability while keeping processing load and energy requirements low.

[0031] In some embodiments, the leader 102 performs frequency synchronization with one or more of the devices 104, 106, or 108. Frequency synchronization is used to ensure that the carrier frequency of the devices is matched to the carrier frequency of the leader, so that transmission takes place within the same frequency reference. Precise frequency matching reduces demodulation errors and enables reliable communication, especially in devices that generate an internal carrier independent of the carrier transmitted by the leader. Frequency synchronization is achieved by using dedicated signaling, such as a dedicated frequency synchronization signal or a preamble configured to transmit frequency reference information. These signals are transmitted periodically, semi-permanently, or on demand, so that the leader can maintain frequency matching with multiple devices operating under different energy and oscillator conditions in the AIOT environment 100.

[0032] In several exemplary configurations, different techniques are employed to support frequency synchronization between the leader 102 and devices 104, 106, and 108. In the first method, frequency synchronization is enabled by using a special preamble included in the reader-to-device (R2D) transmission. The preamble for frequency synchronization includes multiple sequences having different patterns. Each sequence is generated using a Gold sequence or M sequence to ensure autocorrelation characteristics and reduce cross-correlation between devices. Different sequences are associated with different device identifiers so that multiple devices can be distinguished during synchronization. The multiple sequences for frequency synchronization may be configured by the leader based on the number of devices operating in the AIOT environment 100. In this configuration, the leader selects and transmits a specific sequence from the multiple sequences to perform frequency matching with a particular device. For example, if a device sends a frequency synchronization request via a D2R transmission, the leader responds with an R2D transmission containing the special preamble. If no synchronization request is received, the leader continues with an R2D transmission containing a normal preamble used for timing acquisition or data communication.

[0033] Alternatively, frequency synchronization is performed using a dedicated signal referred to herein as the AIOT Frequency Synchronization Signal (A-FSS). The A-FSS is transmitted as part of the PRDCH and is used for broadcast synchronization from a single reader to multiple devices. The A-FSS is transmitted with or without R2D data or control information. When the A-FSS and R2D data or control signals are transmitted in the same PRDCH slot or time occasion, the reader transmits these signals using time division multiplexing (TDM). When only the A-FSS is transmitted in the PRDCH, the preamble preceding the transmission includes a clock acquisition signal different from the clock acquisition signal used in preambles for data transmission or composite transmission. In particular, in the clock acquisition section of the preamble preceding a PRDCH transmission that transmits only the A-FSS, indications of chip length, such as the number of OOK chips per OFDM symbol, are omitted. The A-FSS uses an OFDM-based waveform employing OOK-1 or OOK-4 modulation. The number of chips per OOK symbol is indicated by M. A larger M value results in higher time accuracy. For example, in OOK-4 modulation, M values ​​of 1, 2, 4, 8, 16, or 24 are used to achieve the desired synchronization accuracy. The reader sets the same or different OOK modulation schemes and the same or different M values ​​for A-FSS and AIOT data transmissions to balance synchronization accuracy and power efficiency.

[0034] In some embodiments, A-FSS is transmitted via broadcast from a single reader to multiple devices within the AIOT environment 100. The preamble used for A-FSS differs from the preamble used for standard R2D data transmission. The clock acquisition portion of the OOK-based preamble without line coding includes rising and falling edges to indicate to devices that the subsequent PRDCH transmission is dedicated to A-FSS. The control part preceding the A-FSS includes a device identifier or device group identifier to identify devices that are permitted to detect or process PRDCH dedicated to A-FSS. The control information associated with PRDCH dedicated to A-FSS includes at least parameters such as time-domain resources, frequency-domain resources, code rate, device or group identifier, duration of the OOK chip, and number of repetitions. In some configurations, the start instruction portion or clock acquisition portion of the preamble is specifically defined for A-FSS transmission and used solely for that purpose. When such a dedicated preamble is used, the dedicated preamble itself provides sufficient signaling for the device to recognize and decode the A-FSS transmission, and therefore Layer 1 (L1) control information is omitted.

[0035] In some exemplary configurations, A-FSS is time-division multiplexed with data in R2D transmissions. Various techniques are used to encode control information transmitted in the PRDCH. In one exemplary method, the control unit includes resource allocation information for both R2D or D2R data and A-FSS transmissions. The control information includes time-domain resources for both D2R and A-FSS, frequency-domain resources for both D2R and A-FSS, code rates for R2D, D2R, and A-FSS, device or group identifiers for R2D, D2R, and A-FSS, duration of the OOK chip for R2D, D2R, and A-FSS, and the number of repetitions for R2D, D2R, and A-FSS transmissions. This configuration allows the reader to efficiently allocate resources, simultaneously coordinate data transmission and frequency synchronization operations within the same transmit slot, and improve spectral efficiency while maintaining low-power operation suitable for AIOT deployments.

[0036] In some exemplary configurations, alternative methods are used to define control information related to A-FSS. Instead of including complete resource allocation information in the control unit, a simplified indicator is provided to identify whether or not A-FSS is being transmitted. If the indicator indicates the presence of A-FSS, the relevant information (e.g., time-domain and frequency-domain resources, modulation and coding scheme-like information, device or group identifier, chip duration, and repetition count) is included within a media access control element (MAC-CE) contained in the R2D data portion of the transmission. The transmission bandwidth of the PRDCH transmitting A-FSS is the same as the transmission bandwidth of the PRDCH used for standard R2D transmission. The PRDCH containing A-FSS is time-division multiplexed or frequency-division multiplexed with other PRDCHs transmitting R2D data. In some cases, the PRDCH transmitting A-FSS is scheduled by another PRDCH transmitting R2D data, thereby enabling coordinated transmission and efficient resource utilization within the AIOT environment 100.

[0037] The ON-OFF patterns of OOK symbols used in A-FSS are based on one or more binary sequences. To distinguish adjacent readers, one of several alternative methods is used. In the first alternative method, for example, multiple readers operating using time-division multiplexing share a single binary sequence. In the second alternative method, for example, multiple different binary sequences are assigned to different readers. Due to potential timing offsets resulting from sampling frequency offsets, if the same sequence is used by both, the AIOT device may incorrectly synchronize with A-FSS transmitted by a neighboring reader. Therefore, multiple sequences are used to distinguish A-FSS transmissions from different readers. The A-FSS sequence used by a reader is configured in one of two ways. In the first option, the sequence is explicitly configured by the reader based on the necessary configuration information transmitted via an AIOT paging message or another R2D broadcast. In the second option, the sequence is determined based on predefined rules, such as cyclic shifts, used to identify the reader.

[0038] When a sequence is explicitly configured, the configuration information includes the modulation format, which is on-off keying, binary phase-shift keying, or binary frequency-shift keying; the number of binary A-FSS sequences used in the ON-OFF pattern; the period of the A-FSS transmission; and the transmission type, which is aperiodic, periodic, or semi-permanent. Existing pseudo-random sequences, such as M sequences, gold sequences, or computer-generated sequences with good autocorrelation and cross-correlation characteristics, can be used as the binary A-FSS sequence pattern. The same type of binary sequence is also used in the preamble in R2D transmission. The number of binary A-FSS sequences is, for example, 3, 4, 8, or 16. The sequence length includes an M sequence of length 128 (M equal to 8), an M sequence of length 256 (M equal to 16), or a duration equivalent to 4, 8, or 16 OFDM symbols.

[0039] In some exemplary configurations, A-FSS transmissions employ frequency hopping to improve synchronization performance. Frequency hopping is performed between symbols using line coding such as Manchester coding, FM0 coding, or Miller coding. This technique allows A-FSS to provide both time and frequency synchronization to the AIOT receiver using envelope detection. When A-FSS occupies an odd number of symbols, the position of the carrier frequency in the spectrum changes from symbol to symbol. For example, by alternating the carrier frequency in consecutive symbols, frequency diversity can be achieved, improving robustness against interference.

[0040] A-FSS transmissions can be aperiodic, periodic, or semi-persistent. For aperiodic transmissions, an AIOT device supporting A-FSS reception sends an A-FSS transmission request signal via PRDCH. Upon receiving the request, the reader includes configuration information, such as the transmission duration, in the paging message. In some cases, the reader initiates aperiodic A-FSS transmissions by directly including the configuration information in the paging message without receiving a device request. For periodic transmissions, the A-FSS period is configured based on synchronization requirements, ranging, for example, from approximately 160 milliseconds to approximately 10.24 seconds. This period setting is included in the paging message or other R2D broadcast used to trigger the initial synchronization procedure. For semi-persistent transmissions, the A-FSS configuration information is also included in the paging message, and an R2D transmission carrying either the paging message or data triggers a subsequent A-FSS transmission. After receiving the trigger signal in the R2D transmission, the device expects to receive a first A-FSS within a defined time window, such as between a minimum and maximum offset relative to the trigger transmission.

[0041] A-FSS transmissions also support group-based communication, or group casts, in which case the paging message includes an identifier associated with the group of devices selected to receive the A-FSS. A different preamble is used for each group identifier to identify group transmissions. This group-based configuration allows the leader to efficiently synchronize multiple devices that share similar timing or frequency requirements while minimizing signaling overhead.

[0042] As described above, devices in an AIOT environment are implemented as various different device types. Therefore, for further explanation, Figure 2 shows an example of an AIOT device configured for synchronization according to an embodiment of the present invention and implemented as device 2A. Device 200 includes components configured to receive energy and data from a reader and transmit information to the reader using either active communication or backscatter communication, depending on the available energy and operating conditions. Device 200 is an example of a low-power device that depends on harvested energy and includes an internally generated carrier wave for a particular transmission operation. As illustrated, device 200 includes an antenna 202, an energy harvester 204, and a communication and processing subsystem configured to perform signal reception, demodulation, modulation, and data processing. The configuration of these components may vary for each implementation of the AIOT device depending on energy requirements, transmission distance, and application constraints.

[0043] As shown in Figure 2, device 200 includes an antenna 202, which is shared for both the RF energy harvester and the receiver or transmitter functions, or is implemented separately. Antenna 202 receives incident radio frequency (RF) signals from the reader and radiates backscattered or actively generated signals toward the reader. Antenna 202 is coupled to a matching network 206. The matching network 206 matches the impedance between antenna 202 and other components, including the RF energy harvester 208 and various receiving-related circuit blocks, if present, to ensure efficient power transmission and signal integrity.

[0044] Devices configured as shown in Figure 2, such as device 200, operate intermittently based on the amount of energy available from energy harvesters 204 and 208, and therefore cannot maintain a continuous internal frequency or timing reference. Due to this characteristic, this type of device relies on a synchronization signal from the reader to achieve accurate communication matching. Device 200 uses the start instruction of the preamble transmitted by the reader to detect the start of transmission from the reader to the device and activates the receiving circuit at the appropriate timing. Device 200 also uses the clock acquisition section of the preamble to determine timing parameters such as the duration of the on / off keying chip and matches the device clock with the reader's transmission timing. Furthermore, device 200 uses frequency synchronization signaling, such as an AIOT frequency synchronization signal, to match the internally generated carrier frequency with the reader's carrier frequency. These synchronization operations allow the device configured as shown in Figure 2 to compensate for timing drift, oscillator inaccuracies, and energy-related interruptions, enabling reliable reception and transmission in an AIOT environment.

[0045] Device 200 may include one or both of energy harvesters, such as an energy harvester 204 that extracts energy from a non-RF source (e.g., solar energy or vibrational energy) and an RF energy harvester 208 that collects energy from an incident RF signal received via an antenna 202. The energy harvested by one or both of the energy harvesters 204 and 208 is led to a power management unit (PMU) 210 and stored in an energy reservoir 212. The energy reservoir 212 includes capacitors or other charge storage elements to store the harvested energy for later use. The PMU 210 manages both the transfer of energy from the energy harvesters 204 and 208 to the energy reservoir 212 and the distribution of power from the energy reservoir 212 to other active components of Device 200. Thus, the PMU 210 supplies operating power to functional blocks when energy is available and stops or reduces power supply when the energy storage is low.

[0046] On the receiver side, a radio frequency bandpass filter (RF BPF) 214 improves selectivity by allowing signals within a predetermined frequency band to pass through and attenuating out-of-band interference. Depending on the implementation, the RF BPF 214 may be omitted to reduce power consumption or circuit complexity. In some embodiments, a low-noise amplifier (LNA) 216 is used to amplify the received RF signal to improve the receiver's sensitivity. At least one of the R2D signal, carrier-to-device (CW2D) signal, and D2R signal is amplified by either a reflection amplifier 242 or an LNA 216, depending on the device configuration and available power.

[0047] The envelope filter 218 recovers modulation data or synchronization information by detecting the envelope of the received RF signal. The baseband amplifier (BB amp) 220 ensures signal strength suitable for subsequent processing by amplifying the detected baseband signal. The baseband low-pass filter (BB LPF) 222 removes high-frequency components and harmonics, improving signal quality before further demodulation or digitization. Depending on the implementation, the BB LPF 222 may be omitted for simplification or to improve power efficiency. The comparator or N-bit analog-to-digital converter (ADC) 224 converts the analog baseband signal into a digital representation suitable for further digital processing within the device 200.

[0048] The digital baseband (BB) logic 226 includes a decoder 228, a controller 230, and an encoder 232. The decoder 228 reconstructs data, control information, or synchronization patterns by interpreting digital information received from a comparator or ADC 224. The controller 230 manages the operation of the entire device, including the coordination of receive, process, and transmit functions, and also controls the switching of power between circuit blocks depending on energy availability. The encoder 232 generates digital transmit data for backscatter or active transmission by applying the modulation patterns or coding protocols required for communication with the reader. The BB logic 226 is coupled to a memory 234, which stores data and operating parameters. The memory 234 includes non-volatile memory (NVM), such as an EEPROM, used for permanently storing identifiers or configuration data, and volatile storage (such as registers), used for temporarily holding operating information while power remains in the energy reservoir 212. The clock generator 236 supplies the clock signals necessary for the timing and synchronization of the digital and analog subsystems.

[0049] On the transmitting side, a backscatter modulator 240 modulates the impedance presented to antenna 202 to generate a backscatter signal that transmits the data provided by BB logic 226. In some configurations, a high-frequency shifter 238 shifts the frequency of the backscatter signal by tens of megahertz, for example, from the downlink (FDD-DL) frequency to the uplink (FDD-UL) frequency. A reflection amplifier 242 extends the transmission range or improves the signal-to-noise ratio by amplifying the backscatter or reflection signal. The applicability of amplification in the reflection path depends on the balance between achievable performance and power consumption constraints. In some configurations, at least one of the R2D, CW2D, or D2R signals is amplified by either the reflection amplifier 242 or LNA 216, depending on which circuit path is active. By using these components together, device 200 performs low-power transmission operation suitable for energy harvesting, power management, processing of received signals, and deployment in AIOT environments.

[0050] For further explanation, Figure 3 shows an exemplary AIOT device implemented as device 2B and configured for synchronization according to an embodiment of the present invention. Device 300 includes components configured to receive energy and data from a reader and transmit information to the reader using an active transmitter chain, in addition to backscatter-aware receiving capabilities via an RF envelope detector receiver. Device 300 is an example of a low-power device that relies on harvested energy and generates a carrier frequency for transmission using a local oscillator. As shown, device 300 includes an antenna 302, an energy harvesting subsystem, and a communication processing subsystem configured to perform signal reception, demodulation, modulation, frequency generation, and data processing. The configuration of these components may vary depending on the implementation of the AIOT device, depending on energy requirements, transmission distance, and application constraints.

[0051] As shown in Figure 3, device 300 includes an antenna 302, which is shared for the RF energy harvester and for the receiver or transmitter functions, or is implemented separately. Antenna 302 is coupled to a matching network 306. The matching network 306 matches the impedance between antenna 302 and other components, including the RF energy harvester 308 and receiver-related circuit blocks, if present, to ensure efficient power transmission and signal integrity. One or both energy harvesters are provided. Energy harvester 304 extracts energy from non-RF sources such as light, vibration, or thermal gradients, while RF energy harvester 308 collects energy from incident RF signals received via antenna 302. The harvested energy is led to a PMU 310 and stored in an energy reservoir 312. The PMU310 manages the transfer of energy from the energy harvesters 304 and 308 to the energy storage unit 312, and the distribution of power from the energy storage unit 312 to the active components of the device 300.

[0052] On the receiving end, the RF BPF 314 improves selectivity by attenuating out-of-band interference while allowing signals within the desired bandwidth to pass through. Depending on the implementation, the RF BPF 314 may be omitted to meet power targets. The low-noise amplifier (LNA) 316, if present, improves the strength and sensitivity of the received signal. The RF envelope filter 318 reconstructs baseband information for the RF envelope detector receiver by detecting the envelope of the RF signal. The BB amplifier 320 amplifies the detected baseband signal, and the BB LPF 322 improves the input presented to the comparator or N-bit ADC 324 by removing high-frequency components and harmonics. The comparator or N-bit ADC 324 converts the analog baseband signal into a digital representation suitable for further processing. The digital BB logic 326 includes a decoder 328, a controller 330, and an encoder 332. The decoder 328 interprets the received digital information, the controller 330 coordinates the receive, processing, power management, and transmit operations, and the encoder 332 prepares the transmit data for modulation.

[0053] Memory 334 stores device data and operating parameters and includes non-volatile memory for persistent information and registers for temporary information available while energy remains in the energy storage unit 312. Clock generator 336 supplies the clock signals required for the digital and analog subsystems. On the transmitting side, transmit modulator 338 modulates the baseband bits according to the selected modulation scheme, DAC 340 converts the digital transmit samples into analog format, and low-pass filter 342 suppresses unwanted spectral components. Mixer 344 upconverts the filtered baseband signal to an RF signal using local oscillator (LO) 346 which generates the carrier frequency. Depending on the implementation, frequency-locked loop (FLL) or phase-locked loop (PLL) is used for frequency synthesis within the LO 346. The LO is implemented in various different forms, including phase-locked loop (PLL), frequency-locked loop (FLL), and other schemes conceivable to those skilled in the art. Power amplifier (PA) 348, if present, amplifies the transmit signal before radiation by antenna 302.

[0054] A device configured as shown in Figure 3, device 300, operates intermittently based on the energy available from energy harvesters 304 and 308, generating a carrier wave using LO346. However, the frequency of this carrier wave may drift if the power is switched on or off or if the temperature fluctuates. Due to these characteristics, device 300 relies on synchronization signaling from the reader to achieve accurate communication matching. Device 300 can use the start instruction section of the preamble to detect the start of transmission from the reader to the device and activate the receiving circuit at the appropriate timing. Device 300 can also use the clock acquisition section of the preamble to derive timing parameters such as the duration of the on / off keying chip, and match the device clock with the reader's transmission timing. Furthermore, device 300 can use frequency synchronization signaling, such as the AIOT frequency synchronization signal, to match the carrier frequency of LO346 with the reader's carrier frequency. These synchronization operations allow the device configured as shown in Figure 3 to reduce timing drift, frequency offset, and energy-driven interruptions, thereby enabling reliable reception and active transmission in an AIOT environment.

[0055] For further explanation, Figure 4 shows an example of a timing acquisition signal used for synchronization in an AIOT environment according to various embodiments of the present invention. As shown in Figure 4, an example of a timing acquisition signal 400 used for synchronization in an AIOT environment includes a set of components that enable precise timing and frequency matching between a reader and one or more devices. The timing acquisition signal 400 includes a start instruction unit 402, a clock acquisition unit 404, a PRDCH unit 406, and a post-amble unit 408. Each component plays a specific role in establishing and maintaining synchronization within the AIOT system.

[0056] The start instruction unit 402 includes a defined signal pattern that the device uses to detect the start of transmission from the reader to the device. The start instruction unit 402 allows the device to recognize the start of the timing acquisition signal and activate the receiving circuit at the appropriate time, thereby reducing energy consumption. The pattern in the start instruction unit 402 is different from the data transmission pattern, which allows the device to distinguish the synchronization signaling from normal communication signals.

[0057] The clock acquisition unit 404 includes signals used to represent timing parameters such as the duration of on / off keying chips and other symbol-level timing information, which the device uses to synchronize its internal clock with the reader's transmission timing. In some embodiments, the clock acquisition unit 404 encodes information about the number of OOK chips per OFDM symbol using a sequence of rising and falling edges. By decoding this information, the device can set local timing to match the parameters of subsequent PRDCH transmissions.

[0058] The PRDCH unit 406 represents the data portion of the signal, in which control information or data information is transmitted from the reader to one or more AIOT devices. The PRDCH unit 406 transmits downlink information, including control commands, identifiers, configuration data, or other information necessary for the operation of the devices.

[0059] The post-amble section 408 is transmitted after the PRDCH section 406 and includes one or more symbols indicating the end of a transmission from the reader to the device. The post-amble section 408 helps the device confirm the completion of a received message and functions as a guard interval or isolation interval prior to the next transmission. In some implementations, the post-amble section 408 may include error detection or verification signaling that allows the device to verify the integrity of the timing acquisition signal received. The start instruction section 402, clock acquisition section 404, PRDCH section 406, and post-amble section 408 work together to enable reliable synchronization, timing recovery, and data exchange between a reader and an AIOT device operating under low-power or energy harvesting conditions.

[0060] For further explanation, Figure 5A shows a timing diagram illustrating an example of communication exchange between a reader 502 and a device 504 according to an embodiment of the present invention. In the illustrated example, R2D transmission 506 represents a timing acquisition signal transmitted from the reader 502 to the device 504. The timing acquisition signal includes a preamble having a start instruction and a clock acquisition, which allows the device 504 to detect the start of the R2D transmission and perform timing matching. In the example of Figure 5A, a paging message is not required because the start instruction pattern used by the reader 502 is predefined and known to the device 504. After receiving the R2D transmission 506, the device 504 detects the pattern of the start instruction to determine the start of the transmission and uses the clock acquisition to acquire timing parameters such as the duration of the on / off keying chip. Once the device 504 has completed timing synchronization, it transmits a D2R signal 508 to the reader 502 in response. The D2R signal 508 transmits either an acknowledgment or data transmission depending on the operational status, thereby completing the communication exchange between the reader 502 and the device 504.

[0061] For further explanation, Figure 5B shows a timing diagram representing an exemplary communication exchange between a reader 502 and a device 504, according to an embodiment of the present invention, in which the reader 502 transmits a paging message prior to a timing acquisition signal. In this example, the reader 502 first transmits an R2D transmission 510 containing a paging message. The paging message specifies a sequence or pattern to be used in the start instruction of the subsequent timing acquisition signal. After transmitting the paging message, the reader 502 transmits a second R2D transmission 512 containing a timing acquisition signal having a start instruction and a clock acquisition unit formed according to the sequence indicated in the paging message. The device 504 receives the paging message and prepares to detect the start instruction pattern specified by the reader 502. Subsequently, when the device 504 receives the R2D transmission 512, the device 504 detects the start of the transmission by the start instruction unit and derives the timing parameters necessary for synchronization by the clock acquisition unit. Once the timing adjustment is complete, the device 504 transmits a D2R signal 514 containing an acknowledgment or data information to the reader 502. This procedure enables the dynamic configuration of the start instruction sequence, allowing for flexible operation of the AIOT system in scenarios where the leader 502 selects synchronization parameters on demand.

[0062] For further explanation, Figure 6A shows an example of a signal useful for frequency synchronization in an AIOT environment according to an embodiment of the present invention. Signal 600 includes a series of segments that enable timing and frequency matching between a reader and one or more AIOT devices. As shown, signal 600 includes an A-FSS preamble 602, a start instruction section 604, a clock acquisition section 606, a PRDCH section 608, and a postamble 610. Each segment performs its own specific function that contributes to synchronization and data exchange.

[0063] The A-FSS preamble 602 indicates a frequency synchronization signal used to match the carrier frequency of the device to the carrier frequency of the leader. The A-FSS preamble 602 includes one or more sequences that provide frequency reference information to assist the device in generating its internal carrier. The start indicator 604 includes a predefined pattern that allows the device to detect the start of a transmission from the leader to the device. Upon detecting the start indicator 604, the device activates its receiving circuitry to prepare for receiving the subsequent portion of the signal. The clock acquisition 606 represents a timing reference signal used to transmit parameters such as the duration of an on / off keying chip or symbol interval. The clock acquisition 606 allows the device to synchronize its local clock with the transmission timing of the leader. The PRDCH section 608 includes downlink data or control information transmitted from the leader to one or more devices. The postamble 610 includes error checking symbols or guard symbols to indicate the end of a transmission, to provide a transition between signals, or to ensure clear separation from subsequent transmissions.

[0064] For further explanation, Figure 6B shows an example of a signal used for frequency synchronization in an AIOT environment according to an embodiment of the present invention. Signal 612 represents a specific implementation of the A-FSS signal and includes control information or data information. As shown, signal 612 includes a start instruction unit 614, a clock acquisition unit 616, a control unit 618, a data unit 620, and an A-FSS unit 622.

[0065] The start instruction unit 614 includes a pattern that identifies the start of A-FSS transmission and enables the device to detect the start of the signal. The clock acquisition unit 616 includes timing reference information for the device to align timing parameters, such as chip duration, with the reader. The control unit 618 includes control information such as a device identifier, configuration parameters, or resource allocation data. The data unit 620 includes payload data transmitted from the reader to one or more devices. In some embodiments, the control unit 618 and the data unit 620 are time-division multiplexed within the A-FSS signal. The A-FSS unit 622 functions as a frequency synchronization segment used to align the frequency of an internal oscillator in the device with the frequency of the reader. This configuration allows the A-FSS signal to support both frequency synchronization and communication, improving synchronization accuracy and communication efficiency in an AIOT environment.

[0066] For further explanation, Figure 7A shows a timing diagram representing an exemplary message exchange between a leader 700 and a device 704 in an AIOT environment according to an embodiment of the present invention. In this example, the message exchange is used to perform frequency synchronization between the leader 700 and the device 704. The device 704 first sends a D2R frequency synchronization request 702 to the leader 700. The frequency synchronization request 702 indicates that the device 704 requires a reference signal to match its internally generated carrier frequency to the carrier frequency of the leader 700. In response to the request, the leader 700 sends an R2D signal 706 including an A-FSS preamble. The A-FSS preamble provides frequency reference information that enables the device 704 to adjust the frequency of its internal oscillator or carrier frequency. After receiving the R2D signal 706, the device 704 processes the A-FSS preamble, performs frequency matching, and confirms synchronization with the leader 700. Subsequently, device 704 transmits a D2R signal 708 to leader 700, which includes an acknowledgment or data transmission depending on the operational status. This exchange operation demonstrates a frequency synchronization procedure in which leader 700 responds to the synchronization request by including frequency reference information in a transmission that includes an A-FSS preamble.

[0067] For further explanation, Figure 7B shows a timing diagram representing another exemplary message exchange between a leader 700 and a device 704 in an AIOT environment according to an embodiment of the present invention. In this example, the leader 700 transmits a dedicated A-FSS signal 710 to the device 704. Unlike the exchange operation shown in Figure 7A, the signal 710 is a specific A-FSS transmission rather than a typical R2D transmission that includes only an additional preamble for frequency synchronization. The A-FSS signal 710 includes a frequency reference sequence, such as a gold sequence or M sequence, which enables one or more devices to achieve precise carrier frequency matching with the leader 700. The device 704 receives the A-FSS signal 710, extracts the frequency reference information, and adjusts its internal oscillator or carrier frequency based on that frequency reference information. Once frequency matching is achieved, the device 704 transmits a D2R signal 712 to the leader 700. The D2R signal 712 includes a synchronization acknowledgment or additional communication data. This example illustrates an implementation that provides frequency synchronization to one or more devices in an AIOT environment using a dedicated A-FSS signal.

[0068] For further explanation, Figure 8 is a flowchart illustrating an example of a synchronization method in an AIOT environment according to an embodiment of the present invention. The method illustrated in Figure 8 can be implemented in a system similar to the system shown in Figure 1. The method in Figure 8 is performed by a reader 102 configured to communicate with one or more AIOT devices 104, 106, and 108.

[0069] The method in Figure 8 includes step 802 for generating a timing acquisition signal for an AIOT device. Step 802 for generating a timing acquisition signal for an AIOT device is performed by the leader 102 using a transmitting circuit configured to generate a signal structure suitable for synchronizing a device operating on limited or intermittent energy. The timing acquisition signal is generated to include a preamble having a start instruction and a clock acquisition. The preamble is configured so that a low-power AIOT device can easily detect the start of transmission from the leader to the device and extract timing information from the signal. For example, the leader 102 generates the preamble using on-off keying modulation or another modulation technique that allows detection by an envelope-based receiver on the device side.

[0070] In the method shown in Figure 8, step 802, which generates a timing acquisition signal, includes step 804, which forms a start instruction, having a pattern that identifies the start of a transmission from the reader to the device. Step 804, which forms a start instruction having a pattern that identifies the start of a transmission from the reader to the device, is performed by the reader 102 configuring a specific symbol pattern different from the data transmission pattern so that the AIOT device can uniquely recognize the start of a synchronization signal. In some configurations, the start instruction includes an ON-OFF-ON-OFF sequence or another pattern of on-off keying symbols different from the Manchester coded data pattern. The reader 102 selects a pattern according to a predefined configuration or based on device-specific settings notified via a paging message. This pattern allows the device to activate its receiving circuit and begin timing detection with minimal energy consumption.

[0071] In the method shown in Figure 8, step 802, which generates a timing acquisition signal, also includes step 806, which forms a clock acquisition unit, the clock acquisition unit including signals corresponding to timing parameters associated with the clock acquisition unit and subsequent transmissions from the reader to the device. Step 806, which forms a clock acquisition unit including signals corresponding to timing parameters associated with the clock acquisition unit and subsequent transmissions from the reader to the device, is performed by the reader 102 generating a signal segment that encodes timing parameters such as the number of on / off keying chips per orthogonal frequency division multiplexed symbol. The reader 102 uses rising or falling edges in the signal to represent discrete values ​​of the timing parameters. For example, two edges represent one chip per symbol, and eight edges represent eight chips per symbol. The AIOT device, upon receiving this segment, decodes the number of edges to determine the corresponding timing configuration, thereby synchronizing the local clock to the reader's transmission speed.

[0072] The method in Figure 8 also includes step 808 of transmitting a timing acquisition signal to the AIOT device to enable timing synchronization. Step 808 of transmitting a timing acquisition signal to the AIOT device to enable timing synchronization is performed by the reader 102 via a channel from the physical reader to the device, on which a preamble including a start instruction unit and a clock acquisition unit is transmitted prior to control information or data information. The AIOT device receives the signal, detects the start instruction pattern to decide to start transmission, and uses the clock acquisition unit to establish timing matching. For example, an AIOT device having a configuration similar to device 200 or device 300 can start the energy storage and processing components only after detecting the start instruction pattern, thereby saving energy while maintaining precise timing synchronization with the reader 102. This process enables the AIOT system to achieve reliable communication despite low-power operation and intermittent operation on the device side.

[0073] For further explanation, Figure 9 is a flowchart showing another example of a synchronization method in an AIOT environment according to an embodiment of the present invention. The method in Figure 9 is similar to the method in Figure 8 and includes steps 802 to generate a timing acquisition signal for an AIOT device, step 804 to form a start instruction section, step 806 to form a clock acquisition section, and step 808 to transmit the timing acquisition signal to the AIOT device to enable timing synchronization.

[0074] The method in Figure 9 includes a step 902 in which a paging signal is transmitted prior to the timing acquisition signal. In the method in Figure 9, the paging signal indicates a pattern that is to be included in the timing acquisition signal. Step 902, which transmits the paging signal prior to the timing acquisition signal, is performed by the leader 102 using a transmitting circuit configured to communicate with one or more AIOT devices. The paging signal contains information that identifies the sequence, waveform, or symbolic pattern to be used for the start instruction of the subsequent timing acquisition signal. The leader 102 dynamically selects the pattern based on network conditions, device category, or interference conditions. For example, if multiple AIOT devices are within communication range, the leader 102 transmits different paging signals to different devices, each paging signal specifying a unique start instruction pattern. This technique helps avoid collisions and ensures that each device correctly detects the start of the corresponding timing acquisition signal.

[0075] For further explanation, Figure 10 is a flowchart illustrating an example of a frequency synchronization method in an AIOT environment according to an embodiment of the present invention. The method illustrated in Figure 10 can be implemented in a system similar to the system shown in Figure 1. The method in Figure 10 is performed by a reader 102 that communicates with one or more AIOT devices 104, 106, and 108.

[0076] The method in Figure 10 includes a step 1002 in which the leader receives a request from a device for frequency synchronization. Step 1002 of receiving a request from a device for frequency synchronization is performed by the leader 102 by monitoring the channel from the device to the leader to detect frequency matching request messages indicating oscillator drift, demodulation degradation, or commissioning events. Specifically, device 300 using LO346 sends a short request coded with a device identifier stored in memory 334 when the measured frequency offset exceeds a threshold determined by controller 330. As another example, intermittently operating device 200 requests frequency matching after a power-up event managed by PMU210.

[0077] The method in Figure 10 further includes step 1004, in which the leader transmits an AIOT frequency synchronization signal on a channel from the physical leader to the device, the frequency synchronization signal providing frequency matching to one or more AIOT devices and transmitted in a time-division multiplexing scheme. Step 1004 of transmitting the AIOT frequency synchronization signal is performed by the leader 102 by generating an A-FSS similar in structure to that shown in Figure 6B and scheduling the A-FSS in time with the leader-to-device data within the same physical leader-to-device channel. For example, the leader 102 may allocate the first time interval to a start instruction and clock acquisition section, then to an A-FSS section that transmits a frequency reference sequence, and then configure subsequent time intervals to transmit downlink data addressed to device 104 or a group of devices indicated in the control information. As another example, the leader 102 broadcasts the A-FSS to multiple devices, interleaving short data segments for acknowledgments or configuration updates, thereby providing frequency matching and communication within a single transmission opportunity.

[0078] In another embodiment not shown in Figure 10, the method includes the reader sending a message to the AIOT device in response to a request from the AIOT device, the message including a frequency synchronization-specific preamble similar to that shown in Figure 6B. This embodiment is carried out by the reader 102 selecting a frequency synchronization preamble from a preset set, inserting the selected preamble before the downlink data, and sending a message to the device 200 or device 300 to derive a carrier frequency reference from the frequency synchronization preamble before receiving the subsequent data.

[0079] Figure 11 is a block diagram of electronic devices in a network environment 1100, such as the example of the AIOT environment described above, according to one embodiment. The network environment 1100 includes or operates in conjunction with an AIOT reader, such as the reader 102 in Figure 1, or one or more AIOT devices, such as devices 104, 106, and 108 in Figure 1. Electronic device 1101 functions as an AIOT reader, or part thereof, configured to transmit timing acquisition signals, frequency synchronization signals, and data to an AIOT device, or functions as an AIOT device configured to receive such signals and perform synchronization and data exchange operations within the AIOT environment.

[0080] Referring to Figure 11, the electronic device 1101 in the network environment 1100 communicates with the electronic device 1102 via a first network 1198 (e.g., a short-range wireless communication network) or with the electronic device 1104 or server 1108 via a second network 1199 (e.g., a long-range wireless communication network). The electronic device 1101 in the network environment 1100 corresponds to or includes one of the functional configurations of the leader 102 or the AIOT devices 104, 106, or 108. For example, when configured as a leader, the electronic device 1101 includes a communication module 1190 and an antenna module 1197 adapted to transmit timing acquisition signals and frequency synchronization signals according to the synchronization techniques described with respect to Figures 4 to 10. When configured as an AIOT device, the electronic device 1101 includes energy harvesting circuitry, low-power processing elements, and synchronization logic that operate in conjunction with the components of the leader 102 within the same AIOT network. The electronic device 1101 within the network environment 1100 corresponds to or includes one of the functional configurations of either the leader 102 or the AIOT devices 104, 106, or 108. For example, when configured as a leader, the electronic device 1101 includes a communication module 1190 and an antenna module 1197 adapted to transmit timing acquisition signals and frequency synchronization signals in accordance with the synchronization techniques described with respect to Figures 4 to 10. When configured as an AIOT device, the electronic device 1101 includes an energy harvesting circuit, low-power processing elements, and synchronization logic that operate in conjunction with the components of the leader 102 within the same AIOT network.

[0081] Electronic device 1101 communicates with electronic device 1104 via server 1108. Electronic device 1101 includes a processor 1120, memory 1130, input device 1150, acoustic output device 1155, display device 1160, audio module 1170, sensor module 1176, interface 1177, haptic module 1179, camera module 1180, power management module 1188, battery 1189, communication module 1190, subscriber identification module (SIM) card 1196, or antenna module 1197. In one embodiment, at least one component (e.g., display device 1160 or camera module 1180) may be omitted from electronic device 1101, or one or more other components may be added to electronic device 1101. Some of the components are implemented as a single integrated circuit (IC). For example, the sensor module 1176 (e.g., a fingerprint sensor, an iris sensor, or an illuminance sensor) can be incorporated into the display device 1160 (e.g., a display).

[0082] The processor 1120 executes software (e.g., program 1140) for controlling at least one other component (e.g., a hardware component or a software component) of the electronic device 1101 coupled with the processor 1120, and performs various data processing or calculations.

[0083] As part of data processing or computation, the processor 1120 loads commands or data received from other components (e.g., sensor module 1176 or communication module 1190) into volatile memory 1132, processes the commands or data stored in volatile memory 1132, and stores the resulting data in non-volatile memory 1134. The processor 1120 includes a main processor 1121 (e.g., a central processing unit (CPU) or application processor (AP)) and auxiliary processors 1123 (e.g., graphics processing unit (GPU), image signal processor (ISP), sensor hub processor, or communication processor (CP)) that can operate independently of or in conjunction with the main processor 1121. Furthermore, or alternatively, the auxiliary processors 1123 are adapted to consume less power than the main processor 1121 or to perform specific functions. The auxiliary processors 1123 may be implemented separately from the main processor 1121 or as part of the main processor 1121.

[0084] The auxiliary processor 1123 controls at least some of the functions or states related to at least one component of the electronic device 1101 (e.g., the display device 1160, the sensor module 1176, or the communication module 1190) on behalf of the main processor 1121 when the main processor 1121 is inactive (e.g., in sleep mode), or together with the main processor 1121 when the main processor 1121 is active (e.g., running an application). The auxiliary processor 1123 (e.g., an image signal processor or a communication processor) may be implemented as part of another component functionally related to the auxiliary processor 1123 (e.g., a camera module 1180 or a communication module 1190).

[0085] Memory 1130 stores various data used by at least one component of the electronic device 1101 (e.g., processor 1120 or sensor module 1176). This various data includes, for example, software (e.g., program 1140) and input or output data for commands related to the software. Memory 1130 includes volatile memory 1132 or non-volatile memory 1134. Non-volatile memory 1134 includes internal memory 1136 and / or external memory 1138. When the electronic device 1101 functions as an AIOT reader, program 1140 or application 1146 stored in memory 1130 includes instructions executable by processor 1120 to perform operations such as generating timing acquisition signals, forming start instruction and clock acquisition units, or transmitting frequency synchronization signals. When the electronic device 1101 functions as an AIOT device, program 1140 includes instructions to detect a start instruction sequence, decode clock acquisition information, or adjust timing and frequency parameters in response to synchronization signals received from the reader.

[0086] The program 1140 is stored in memory 1130 as software and includes, for example, an operating system (OS) 1142, middleware 1144, or an application 1146.

[0087] The input device 1150 receives commands or data from outside the electronic device 1101 (e.g., a user) that are used by another component of the electronic device 1101 (e.g., a processor 1120). The input device 1150 may include, for example, a microphone, a mouse, or a keyboard.

[0088] The acoustic output device 1155 outputs an acoustic signal to the outside of the electronic device 1101. The acoustic output device 1155 includes, for example, a speaker or a receiver. The speaker is used for general purposes such as multimedia or playback of recordings and videos, while the receiver is used for receiving incoming calls. The receiver may be implemented separately from the speaker or as part of the speaker.

[0089] The display device 1160 provides information visually to an external party (e.g., a user) outside of the electronic device 1101. The display device 1160 includes, for example, a display, a hologram device, or a projector, and a control circuit that controls the corresponding one of the display, hologram device, and projector. The display device 1160 includes a touch circuit adapted to detect touches, or a sensor circuit (e.g., a pressure sensor) adapted to measure the strength of the force produced by a touch.

[0090] The audio module 1170 converts sound into electrical signals and vice versa. The audio module 1170 acquires sound via the input device 1150 or outputs sound via headphones of an external electronic device 1102 that is directly (e.g., wired) or wirelessly coupled to the sound output device 1155 or the electronic device 1101.

[0091] The sensor module 1176 detects the operating state of the electronic device 1101 (e.g., power or temperature) or the external environmental state of the electronic device 1101 (e.g., user status), and generates an electrical signal or data value corresponding to the detected state. The sensor module 1176 includes, for example, a gesture sensor, a gyroscope 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.

[0092] Interface 1177 supports one or more designated protocols used to connect the electronic device 1101 to an external electronic device 1102 directly (e.g., wired) or wirelessly. Interface 1177 may 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.

[0093] The connection terminal 1178 includes a connector that physically connects the electronic device 1101 to an external electronic device 1102. The connection terminal 1178 includes, for example, an HDMI connector, a USB connector, an SD card connector, or an audio connector (for example, a headphone connector).

[0094] The tactile module 1179 converts electrical signals into mechanical stimuli (e.g., vibration or motion) or electrical stimuli that can be perceived by the user via touch or muscle sensation. The tactile module 1179 includes, for example, a motor, a piezoelectric element, or an electrical stimulator.

[0095] The camera module 1180 captures still images or videos. The camera module 1180 includes one or more lenses, an image sensor, an image signal processor, or a flash. The power management module 1188 manages the power supplied to the electronic device 1101. The power management module 1188 can be implemented, for example, as at least part of a power management integrated circuit (PMIC).

[0096] The battery 1189 supplies power to at least one component of the electronic device 1101. The battery 1189 includes, for example, a non-rechargeable primary battery, a rechargeable secondary battery, or a fuel cell.

[0097] The communication module 1190 supports establishing a direct (e.g., wired) communication channel or a wireless communication channel between the electronic device 1101 and an external electronic device (e.g., electronic device 1102, electronic device 1104, or server 1108), and communicating over the established communication channel. The communication module 1190 may include one or more communication processors that can operate independently of the processor 1120 (e.g., AP) and support direct (e.g., wired) communication or wireless communication. The communication module 1190 may also include a wireless communication module 1192 (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 1194 (e.g., a local area network (LAN) communication module or a power line communication (PLC) module). One of these communication modules communicates with an external electronic device via a first network 1198 (e.g., a short-range communication network such as BLUETOOTH®, Wireless Fidelity® (Wi-Fi®) Direct, or an Infrared Data Association (IrDA) standard) or a second network 1199 (e.g., a long-range communication network such as a cellular network, the Internet, or a computer network (e.g., a LAN or Wide Area Network (WAN))). These various types of communication modules may be implemented as a single component (e.g., a single IC) or as multiple components separated from each other (e.g., multiple ICs). The wireless communication module 1192 identifies and authenticates the electronic device 1101 in a communication network such as the first network 1198 or the second network 1199 using subscriber information (e.g., International Mobile Subscriber Identification Number (IMSI)) stored in the SIM card 1196. In the AIOT implementation, the communication module 1190 and the antenna module 1197 work together to perform the function of a transceiver for the reader 102, or a transceiver for an AIOT device such as device 104, 106, or 108.For example, if electronic device 1101 is configured as a reader, communication module 1190 generates an A-FSS or timing acquisition signal using a channel from the physical reader to the device and transmits it to one or more AIOT devices. If electronic device 1101 is configured as an AIOT device, communication module 1190 receives such a signal, extracts synchronization information, and responds by transmitting it from the device to the reader.

[0098] The antenna module 1197 transmits or receives signals or power to or from the outside of the electronic device 1101 (e.g., an external electronic device). The antenna module 1197 includes one or more antennas from which at least one antenna suitable for a communication scheme used in a communication network such as the first network 1198 or the second network 1199 is selected, for example, by the communication module 1190 (e.g., the wireless communication module 1192). The signal or power is then transmitted or received between the communication module 1190 and the external electronic device via the selected at least one antenna.

[0099] Commands or data are transmitted or received between electronic device 1101 and external electronic device 1104 via server 1108, which is connected to a second network 1199. Electronic devices 1102 and 1104 may each be of the same type as electronic device 1101 or of a different type. All or part of the operations performed by electronic device 1101 may be performed by one or more of the external electronic devices 1102, 1104, or server 1108. For example, if electronic device 1101 is to perform a function or service automatically or in response to a request from a user or other device, electronic device 1101 requests one or more external electronic devices to perform at least part of that function or service instead of performing it, or in addition to performing that function or service. One or more external electronic devices that receive the request perform at least part of the requested function or service, or any additional functions or services related to the request, and transfer the result of the execution to electronic device 1101. The electronic device 1101 provides the result, whether or not it has been further processed, as at least part of the response to the request. For this purpose, for example, cloud computing, distributed computing, and client-server computing technologies can be used. In the context of an AIOT environment, the server 1108 represents a cloud or edge processing node configured to coordinate synchronization between multiple readers and AIOT devices, stores configuration information for timing and frequency synchronization, or delivers updates to readers and devices operating under the synchronization methods described in Figures 4 to 10.

[0100] The embodiments and operations of the present invention described herein can be implemented in digital electronic circuits, or in computer software, firmware, or hardware (including the structures disclosed herein and their structural equivalents), or in one or more combinations thereof. The embodiments of the present invention described herein can be implemented as one or more computer programs, i.e., as one or more modules of computer program instructions encoded on a computer storage medium for the execution of operations by a data processing device, or for the control of operations by a data processing device. Furthermore, or alternatively, the program instructions can be encoded into artificially generated propagating signals, such as mechanically generated electrical signals, optical signals, or electromagnetic signals, which are generated to encode information for transmission to a suitable receiving device for execution by a data processing device. The computer storage medium can be, or include, a computer-readable storage device, a computer-readable storage board, a memory array or device for random access or serial access, or a combination thereof. Furthermore, although the computer storage medium is not a propagating signal, the computer storage medium can be a source or destination for computer program instructions encoded with artificially generated propagating signals. Computer storage media may also be one or more separate physical components or media (e.g., multiple CDs, disks, or other storage devices), or may be included therein. Furthermore, the operations described herein may be performed as operations performed by a data processing device on data stored in one or more computer-readable storage devices, or on data received from other sources.

[0101] This specification contains many specific implementation details, but these implementation details should not be interpreted as limitations on the technical scope of the invention, but rather as descriptions of features specific to particular embodiments. Certain features described herein in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, various features described in the context of a single embodiment may also be implemented separately or in any appropriate sub-combination in multiple embodiments. Furthermore, features are described as acting in certain combinations, but one or more features from such combination may be omitted in some cases, and may relate to sub-combinations or variations of sub-combinations.

[0102] Similarly, while the actions are depicted in a specific order in the diagrams, this should not be understood as requiring that such actions be performed in a specific illustrated order or sequential order, or that all illustrated actions be performed, in order to achieve a preferred result. In some situations, multitasking or parallel processing may be advantageous. Furthermore, the separation of various system components in the embodiments described above should not be understood as requiring such separation in all embodiments, and the described program components and systems can generally be integrated in a single software product or packaged in multiple software products.

[0103] Thus, specific embodiments of the present invention have been described herein. Other embodiments may still obtain favorable results even if the operations described in the technical scope of the invention are performed in a different order. Furthermore, the steps depicted in the drawings do not necessarily require the specific order or sequence shown to obtain favorable results. In certain implementations, multitasking or parallel processing may be advantageous.

[0104] As those skilled in the art will recognize, the innovative concepts described herein are modifiable and adaptable for a wide range of applications. Therefore, the technical scope of the present invention is not limited to the specific exemplary teachings described above. [Explanation of symbols]

[0105] 100 Environment 102 Leaders 104, 106, 108, 200, 300 devices 202, 302 antennas 204, 304 Energy Harvesters 206, 306 Matching Network 208, 308 RF Energy Harvester 210, 310 Power Management Unit (PMU) 212, 312 energy storage units 214, 314 Radio frequency bandpass filter (RF BPF) 216, 316 Low-noise amplifiers (LNAs) 218, 318 (RF) envelope filters 220, 320 Bassband Amplifier (BB Amplifier) 222, 322 Baseband Low-Pass Filter (BB LPF) 224, 324 comparators or N-bit analog-to-digital converters (ADCs) 226, 326 Digital Baseband (BB) Logic 228, 328 decoders 230, 330 controllers 232, 332 encoders 234, 334, 1130 memory 236, 336 Clock Generator 238 High-Frequency Shifter 240 Backscatter modulator 242 Reflection Amplifier 338 Transmitter modulator 340 DAC 342 Low-pass filter 344 Mixer 346 Local Oscillator (LO) 348 Power Amplifier (PA) 1100 Network Environment 1101, 1102, 1104 Electronic Devices 1108 Server 1120 processors 1121 Main Processor 1123 Auxiliary processor 1140 Programs 1150 Input Device 1155 Acoustic output device 1160 Display device 1170 Audio Module 1176 Sensor Module 1177 Interface 1178 Connection terminals 1179 Tactile Module 1180 Camera Module 1188 Power Management Module 1189 Battery 1190 Communication Module 1196 SIM card (subscriber identification module) 1197 Antenna Module 1198 The first network 1199 Second Network

Claims

1. It is a method, The leader generates a timing acquisition signal for an ambient IoT (AIOT) device, The leader includes the step of transmitting the timing acquisition signal to the AIOT device in order to enable timing synchronization, The timing acquisition signal includes a preamble having a start instruction unit and a clock acquisition unit. The above generation step is, The start instruction unit is formed to have a pattern that identifies the start of transmission from the reader to the device, A method characterized by comprising forming the clock acquisition unit, which includes a signal corresponding to timing parameters associated with the clock acquisition unit and subsequent transmission from the reader to the device.

2. The method according to claim 1, characterized in that the pattern includes an ON-OFF-ON-OFF sequence.

3. The method according to claim 1, characterized in that the pattern is composed of the leader.

4. The method of 3, further comprising the step of transmitting a paging signal by the reader prior to the timing acquisition signal, wherein the paging signal indicates the pattern of the start instruction portion of the preamble.

5. The method according to claim 1, characterized in that the pattern is predefined for all timing acquisition signals transmitted by the reader.

6. The method according to claim 1, characterized in that the signal corresponding to the timing parameter includes the number of rising and falling edges encoding the timing parameter.

7. The method according to 6, characterized in that the timing parameter represents the number of on / off keying chips per orthogonal frequency division multiplexed symbol.

8. The method according to claim 1, further comprising the reader sending a message to the AIOT device in response to a request from the AIOT device, wherein the message includes a preamble specific to frequency synchronization.

9. The method according to claim 1, further comprising the reader transmitting an AIOT frequency synchronization signal in a channel from the physical reader to a device, wherein the frequency synchronization signal provides frequency matching for one or more AIOT devices.

10. The method according to 9, characterized in that the AIOT frequency synchronization signal is transmitted in the channel from the physical reader to the device by time-division multiplexing with the data signal and control signal from the reader to the device.

11. An apparatus comprising at least one processing device and a memory coupled to the processing device, wherein the memory, when executed by the processing device, provides the apparatus with To generate timing acquisition signals for ambient IoT (AIOT) devices, To enable timing synchronization, the system stores a command to transmit the timing acquisition signal to the AIOT device, The timing acquisition signal includes a preamble having a start instruction unit and a clock acquisition unit. The above generation is, The start instruction unit is formed to have a pattern that identifies the start of transmission from the reader to the device, The apparatus is characterized by comprising: forming the clock acquisition unit which includes the clock acquisition unit and a signal corresponding to timing parameters associated with the transmission from the subsequent reader to the device.

12. The apparatus according to claim 11, characterized in that the pattern includes an ON-OFF-ON-OFF sequence.

13. The apparatus according to claim 11, wherein the pattern is configured by the apparatus, the apparatus transmits a paging signal prior to the timing acquisition signal, and the paging signal indicates the pattern which will be included in the timing acquisition signal.

14. The apparatus according to claim 11, characterized in that the pattern is predefined for all timing acquisition signals transmitted by the apparatus.

15. The apparatus according to claim 11, wherein the apparatus transmits an AIOT frequency synchronization signal that is transmitted in a time-division multiplexed manner with data signals and control signals from the reader to the device in a channel from the physical reader to the device, and the frequency synchronization signal provides frequency matching for one or more AIOT devices.

16. When executed by at least one processing device, the processing device performs the following: To generate timing acquisition signals for ambient IoT (AIOT) devices, A computer program product including a computer-readable medium containing instructions to transmit the timing acquisition signal to the AIOT device in order to enable timing synchronization, The timing acquisition signal includes a preamble having a start instruction unit and a clock acquisition unit. The above generation is, The start instruction unit is formed to have a pattern that identifies the start of transmission from the reader to the device, A computer program product characterized by comprising: forming the clock acquisition unit which includes the clock acquisition unit and the clock acquisition unit which includes a signal corresponding to timing parameters associated with the subsequent transmission from the reader to the device.

17. The computer program product according to claim 16, characterized in that the pattern includes an ON-OFF-ON-OFF sequence.

18. The computer program product according to claim 16, characterized in that the pattern is configured by the processing device, the processing device transmits a paging signal prior to the timing acquisition signal, and the paging signal indicates the pattern which will be included in the timing acquisition signal.

19. The computer program product according to claim 16, characterized in that the pattern is predefined for all timing acquisition signals transmitted by the processing device.

20. The computer program product according to claim 16, wherein the processing device transmits an AIOT frequency synchronization signal that is transmitted in a time-division multiplexed manner with data signals and control signals from the reader to the device in a channel from the physical reader to the device, and the frequency synchronization signal provides frequency matching for one or more AIOT devices.

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