Uplink transmission control for ambient IoT devices

Abstract

The present document relates to a method and apparatuses for controlling uplink transmission in consideration of the characteristics of ambient IoT devices. For this purpose, a method for controlling an uplink transmission scheme of a reader comprises: transmitting downlink signals to ambient IoT devices; receiving first uplink signals from the ambient IoT devices; and controlling a transmission scheme of second uplink signals following the first uplink signals from the ambient IoT devices, wherein the downlink signals are not used for channel measurement, flow control, and forward error correction (FEC), the first and second uplink signals are used to selectively perform one or more of channel measurement, flow control, and FEC, and controlling the transmission scheme of the second uplink signals includes controlling the transmission scheme in consideration of the reception state of the first uplink signals on a group basis of the ambient IoT devices.

Description

Uplink transmission control of ambient IoT devices

[0001] The following description relates to a mobile communication system supporting the Ambient IoT (Internet of Things), and more specifically, to an uplink transmission control method and devices therefor that take into account the characteristics of ambient IoT devices.

[0002] 3GPP (3rd Generation Partnership Project), which leads the technical standards for mobile communication systems rd The Generation Partnership Project (GPP) introduced various technologies to support IoT devices in LTE and 5G.

[0003] Figure 1 is a diagram briefly summarizing the requirements of IoT devices considered by 3GPP.

[0004] The drawing in Fig. 1 is data presented at the 19th GSMA 5G IoT Strategy Group Meeting (January 2022), and compares the performance of a passive IoT UE discussed in Rel-18 and being discussed as ambient IoT (hereinafter referred to simply as A-IoT) in Rel-19 with the transmission speed of general NR LTE UE, RedCap UE, LTE-M UE, and NB-IoT UE.

[0005] While other IoT UEs are all powered by batteries, A-IoT devices are being discussed assuming a large number of passive devices that secure their own power through energy harvesting, support low transmission speeds of around 10 kbps, consume very low power of 1 to 100 uW, and cost 10 to 100 times less than NB-IoT UEs. In other words, the pyramid structure of Fig. 1 can be interpreted to mean that A-IoT devices at the very bottom can be attached to more objects than other IoT devices.

[0006] Although various use cases for A-IoT are being discussed, the inventory use case as shown in Figure 2 is being studied most intensively.

[0007] Figure 2 is a drawing for explaining an example of use in an automatic warehouse as an example of the concept of an inventory use case among the use cases of A-IoT.

[0008] The concept of an automated warehouse illustrated in Figure 2 exemplifies the concept of utilizing A-IoT in the stages of checking and unloading (1), entering into inventory (2), storing in inventory (3), retrieving from inventory (4), and checking and loading (5), among which the stages of entering into inventory (2), storing in inventory (3), and retrieving from inventory (4) are used.

[0009] That is, a list of items can be secured using A-IoT at the time of receipt / delivery, and when necessary, a base station (220) or another reader can query a large number of A-IoT devices (210a-210n) in the warehouse to secure data by product group and manufacturer, and transmit this to the A-IoT server (230) (S210).

[0010]

[0011] However, assuming that the A-IoT devices (210a-210n) are deployed in a large number compared to other IoT devices as conceptualized in FIG. 1, it is necessary to consider different transmission methods for downlink signals received from the base station (220) as passive UEs and uplink signals transmitted from the IoT devices (210a-210n) to the base station (220).

[0012]

[0013] Meanwhile, the aforementioned A-IoT technology is based on RFID technology. However, while RFID uses a fixed frequency, eliminating the need for RFID terminals to search for a suitable frequency, A-IoT has not yet standardized how to determine the frequency to use.

[0014] Even if the communication frequency of A-IoT devices is used variably, unlike existing 5G terminals, it is necessary to consider the characteristic that the base station cannot know which functions the A-IoT device supports because it does not use UE capability messages.

[0015] In order to solve the above-described problem, one aspect of the present invention proposes an uplink transmission control method and devices therefor that take into account the characteristics of ambient IoT devices.

[0016] Specifically, we propose a method and a device for selectively applying one or more of channel measurement, flow control, or FEC to uplink signals transmitted by A-IoT devices by considering the reception status of uplink signals in groups, while downlink signals transmitted to A-IoT devices do not perform channel measurement, flow control, and FEC (Forward Error Correction). In this case, flow control may include performing line coding on repeated messages.

[0017] In addition, according to the embodiment, we propose a specific method for configuring the MCS (Modulation and Coding Scheme) applied to the uplink signal to be applied at the end of a round or in the next round, and we specifically specify the uplink transmission method according to the line coding, state, and device type applied to A-IoT devices.

[0018]

[0019] In addition, in order to solve the problem described above, in another aspect of the present invention, assuming an A-IoT device that operates without fixing the frequency, a method for controlling a communication frequency that takes into account the characteristics of the A-IoT device and devices therefor are proposed.

[0020] Specifically, considering the characteristics of A-IoT devices, we propose a method of controlling frequency information by hard-coding the initial frequency (hereinafter referred to as the "first frequency") for each device and using it, and providing information on the frequency (hereinafter referred to as the "second frequency") to be used for actual communication for a predetermined period (T) through a message transmitted through it.

[0021] In addition, according to embodiments, we propose a method for efficiently using the A-IoT communication bandwidth by setting the first frequency described above as a guard band and efficiently providing the location of the second frequency.

[0022] In addition, according to embodiments, a method is proposed to variably control the frequency of use according to the network situation by stipulating that the second frequency be used within a predetermined period (T).

[0023] The problems to be solved by the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by a person having ordinary skill in the technical field to which the present invention belongs from the description below.

[0024] In one aspect of the present invention for solving the above-described problem, a method for controlling an uplink transmission method of ambient IoT devices by a reader in a mobile communication system supporting ambient IoT (Internet of Things) is proposed, comprising: transmitting a downlink signal to the ambient IoT devices; receiving a first uplink signal from the ambient IoT devices; and controlling a transmission method of a second uplink signal subsequent to the first uplink signal of the ambient IoT devices, wherein the downlink signal does not perform channel measurement, flow control, and FEC (Forward Error Correction), and the first and second uplink signals selectively perform at least one of channel measurement, flow control, and FEC, wherein controlling the transmission method of the second uplink signal includes controlling by considering a reception state of the first uplink signal for each group of the ambient IoT devices.

[0025] Meanwhile, in another aspect of the present invention, a method for an ambient IoT device to perform communication with a reader in a mobile communication system supporting the ambient IoT (Internet of Things) is proposed, comprising: receiving a downlink signal from the reader; transmitting a first uplink signal to the reader; receiving a message for controlling a transmission method of a second uplink signal subsequent to the first uplink signal from the reader; and transmitting the second uplink signal to the reader according to the message, wherein the downlink signal does not perform channel measurement, flow control, and FEC (Forward Error Correction), and the first and second uplink signals selectively perform at least one of channel measurement, flow control, and FEC, wherein the message for controlling the transmission method of the second uplink signal is determined in consideration of a reception state of a group unit including the ambient IoT device.

[0026] In addition, in another aspect of the present invention, a reader of a mobile communication system supporting an ambient IoT (Internet of Things) comprises at least one processor; and at least one computer memory operably connected to the at least one processor and storing instructions that, when executed, cause the at least one processor to perform operations, wherein the operations include: transmitting a downlink signal to ambient IoT devices; receiving a first uplink signal from the ambient IoT devices; And, a reader is proposed, which includes controlling a transmission method of a second uplink signal subsequent to the first uplink signal of the ambient IoT devices, wherein the downlink signal does not perform channel measurement, flow control, and FEC (Forward Error Correction), and the first and second uplink signals selectively perform one or more of channel measurement, flow control, and FEC, and the controlling of the transmission method of the second uplink signal includes controlling by considering a reception state of the first uplink signal in units of groups of the ambient IoT devices.

[0027] In addition, in another aspect of the present invention, an ambient IoT device of a mobile communication system supporting the ambient IoT (Internet of Things) comprises at least one processor; and at least one computer memory operably connected to the at least one processor and storing instructions that, when executed, cause the at least one processor to perform operations, wherein the operations include: receiving a downlink signal from a reader; transmitting a first uplink signal to the reader; receiving a message from the reader that controls a transmission method of a second uplink signal subsequent to the first uplink signal; The present invention proposes an ambient IoT device, which includes transmitting the second uplink signal to the reader according to the message, wherein the downlink signal does not perform channel measurement, flow control, and FEC (Forward Error Correction), and the first and second uplink signals selectively perform one or more of channel measurement, flow control, and FEC, and wherein a message controlling a transmission method of the second uplink signal is determined in consideration of a reception state of a group unit including the ambient IoT device.

[0028] At this time, controlling the transmission method of the second uplink signal may include controlling by considering at least one of a ratio of devices in which a CRC (Cyclic Redundancy Check) error of the first uplink signal occurs in units of groups of the ambient IoT devices, an average of the CRC error rates of each of the ambient IoT devices, or a SINR (Signal to Interference plus Noise Ration) of the first uplink signal.

[0029] Specifically, when the ratio of devices in which a CRC error of the first uplink signal occurs or the average of the CRC error rates of each of the ambient IoT devices is equal to or greater than a first threshold or the SINR is equal to or less than a second threshold, the method may include increasing the MCS (Modulation and Coding Scheme) level to apply FEC to the second uplink signal.

[0030] The downlink signal may include information indicating whether FEC is applied to the uplink signal, and the first and second uplink signals may selectively have FEC applied based on the information indicating whether FEC is applied. Meanwhile, the first and second uplink signals may selectively perform one or more of channel measurement, flow control, and FEC depending on whether required coverage can be secured by line coding applied to the first and second uplink signals.

[0031] At this time, controlling the transmission method of the second uplink signal may include increasing the number of chips per symbol when applying line coding, when the ratio of devices in which a CRC (Cyclic Redundancy Check) error of the first uplink signal occurs in units of groups of the ambient IoT devices, when the average of the CRC error rates of each of the ambient IoT devices is equal to or greater than a first threshold, or when the SINR of the first uplink signal is equal to or less than a second threshold.

[0032] Additionally, it may further include transmitting a first query message to the ambient IoT devices, wherein the first uplink signal may be received as a response within a response period for the first query message.

[0033] At this time, increasing the MCS level may additionally include transmitting a message including a command instructing the ambient IoT devices to increase the MCS level within the response period.

[0034] At this time, the second uplink signal may include a signal transmitted by an ambient IoT device in a first state that failed to transmit the first uplink signal based on the MCS level increase command, and a signal retransmitted by an ambient IoT device in a second state that transmitted the first uplink signal but transmitted a signal that was not successfully received by the reader based on the MCS level increase command.

[0035] Alternatively, or in combination therewith, increasing the MCS level may include, after the response period ends, transmitting a command indicating an increase in the MCS level via the second query message when transmitting the second query message to the ambient IoT devices.

[0036] At this time, the second uplink signal may be received as a response within the response period of the second query message.

[0037] In one embodiment of the present invention, the ambient IoT devices can operate in any one of an initial state, a state in which a device ID has been transmitted to the reader, or a state in which a positive response has been received from the reader.

[0038] At this time, controlling the transmission method of the second uplink signal may include transmitting a message including information specifying a response target according to the status of each of the ambient IoT devices.

[0039] The above reader may correspond to a base station or an intermediate medium, and the intermediate medium may include a device portable by the user.

[0040]

[0041] In another aspect of the present invention for solving the above-described problem, a method for securing frequency information for an ambient IoT device to be used for communication in a mobile communication system supporting the ambient IoT (Internet of Things) is proposed, comprising: receiving a first message including a preamble and data from a reader through a first frequency; acquiring second frequency information through the preamble of the first message; and transmitting a second message to the reader through the second frequency, wherein information about the first frequency is hard-coded into the ambient IoT device.

[0042] In another aspect of the present invention for solving the above-described problem, a method for providing frequency information for a reader to use in communication with an ambient IoT device in a mobile communication system supporting the ambient IoT (Internet of Things) is proposed, comprising: transmitting a first message including a preamble and data to the ambient IoT device through a first frequency hardcoded in the ambient IoT device, wherein the preamble of the first message includes second frequency information; and receiving a second message from the ambient IoT device through the second frequency.

[0043] In another aspect of the present invention, an ambient IoT device of a mobile communication system supporting the Ambient IoT (Internet of Things) is proposed, comprising: at least one processor; and at least one computer memory operably connected to the at least one processor and storing instructions that, when executed, cause the at least one processor to perform operations, wherein the operations include receiving a first message including a preamble and data from a reader through a first frequency; obtaining second frequency information through the preamble of the first message; and transmitting a second message to the reader through the second frequency, wherein information about the first frequency is hard-coded into the ambient IoT device.

[0044] In another aspect of the present invention, a reader of a mobile communication system supporting an ambient IoT (Internet of Things) is provided, comprising: at least one processor; and at least one computer memory operably connected to the at least one processor and storing instructions that, when executed, cause the at least one processor to perform operations, the operations comprising: transmitting a first message including a preamble and data to an ambient IoT device via a first frequency hardcoded into the ambient IoT device, the preamble of the first message including second frequency information; and receiving a second message from the ambient IoT device via the second frequency.

[0045] The above first frequency may be located in a guard band among the bandwidths for the ambient IoT of the mobile communication system.

[0046] The preamble of the first message may include difference information from the first frequency to the second frequency.

[0047] Specifically, the difference information may include a frequency offset from the first frequency to a first PRB (Physical Resource Block) of an occupied bandwidth among the ambient IoT bandwidths of the mobile communication system, and a PRB index corresponding to the second frequency.

[0048] Additionally, the ambient IoT device may transmit or receive a signal to or from the reader via the second frequency for a predetermined period of time (T) from at least one of the time points of receiving the first message or transmitting the second message via the second frequency.

[0049] Meanwhile, after the predetermined period (T) has elapsed, the ambient IoT device can monitor the first frequency and receive a third message including a preamble and data from the reader through the first frequency.

[0050] In this case, the third frequency information can be obtained through the preamble of the third message.

[0051] In addition, the mobile communication system supporting the above ambient IoT defines a plurality of types of ambient IoT devices, and the above ambient IoT devices can correspond to a specific type among the plurality of types whose usage frequency can be changed.

[0052] The above multiple types can be distinguished by their peak power consumption level, whether they include amplifiers in one or more of the uplink or downlink, whether they backscattering the uplink transmission signal or generating it internally, and whether their operating frequency can be varied.

[0053] Additionally, the reader corresponds to a base station or an intermediate medium, and the intermediate medium may include a device portable by the user.

[0054] According to the embodiments of the present invention as described above, it is possible to control an uplink transmission method different from a downlink transmission method by taking into account the characteristics of an ambient IoT device.

[0055] Specifically, the downlink signals transmitted to A-IoT devices do not perform channel measurement, flow control, and FEC, but the uplink signals transmitted by A-IoT devices selectively apply one or more of channel measurement, flow control, or FEC by considering the reception status of the uplink signals in groups, thereby efficiently securing coverage for A-IoT services while minimizing the increase in device complexity.

[0056] In addition, according to an embodiment, a specific method of configuring the MCS (Modulation and Coding Scheme) applied to an uplink signal to be applied at the end of a round or in the next round is provided, thereby efficiently coping with various situations of A-IoT communication.

[0057] Additionally, by specifically defining the uplink transmission method according to the line coding, status, and device type applied to A-IoT devices, unnecessary signaling can be minimized.

[0058]

[0059] Meanwhile, according to the embodiments of the present invention as described above, for an A-IoT device that operates without fixing the frequency, the communication frequency can be efficiently controlled by taking into account the characteristics of the A-IoT device.

[0060] Additionally, according to embodiments, the first frequency can be positioned in the guard band to efficiently use the A-IoT communication bandwidth.

[0061] Additionally, according to embodiments, the second frequency can be regulated to be used within a predetermined period (T), thereby allowing the frequency to be variably controlled to suit the network situation.

[0062] The effects that can be obtained from the present invention are not limited to the effects mentioned above, and other effects not mentioned can be clearly understood by a person having ordinary skill in the art to which the present invention belongs from the description below.

[0063] Figure 1 is a diagram briefly summarizing the requirements of IoT devices considered by 3GPP.

[0064] Figure 2 is a drawing for explaining an example of use in an automatic warehouse as an example of the concept of an inventory use case among the use cases of A-IoT.

[0065] FIG. 3 and FIG. 4 are diagrams for explaining a method for a reader to control an uplink transmission method of ambient IoT devices in a mobile communication system supporting A-IoT according to one embodiment of the present invention.

[0066] FIG. 5 is a diagram illustrating an example of an MCS level applicable to an uplink signal in an A-IoT system according to one embodiment of the present invention.

[0067] FIG. 6 is a drawing for explaining the configuration of an A-IoT device according to one embodiment of the present invention.

[0068] FIG. 7 is a diagram for explaining a method of performing uplink signal control in round units according to one embodiment of the present invention.

[0069] FIG. 8 is a diagram for explaining a method of performing uplink signal control within a round according to one embodiment of the present invention.

[0070] FIG. 9 is a table for defining the status of A-IoT devices according to one embodiment of the present invention.

[0071] FIG. 10 is a diagram for explaining a method for an A-IoT device to secure frequency information to be used for communication according to one embodiment of the present invention.

[0072] FIG. 11 is a drawing specifically explaining a frequency to be used by an A-IoT device according to one embodiment of the present invention.

[0073] FIG. 12 is a diagram for explaining the time relationship between receiving a first message and transmitting a second message in response thereto according to one embodiment of the present invention.

[0074] FIG. 13 and FIG. 14 are diagrams for explaining a method for periodically managing the usage frequency of an A-IoT device according to one embodiment of the present invention.

[0075] Figure 15 illustrates a wireless device to which the present technology can be applied.

[0076] Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings so that those skilled in the art can easily implement the present invention. However, the present invention may be implemented in various different forms and is not limited to the embodiments described herein. In addition, in the drawings, parts irrelevant to the description have been omitted to clearly explain the present invention, and similar parts have been designated with similar reference numerals throughout the specification.

[0077] Throughout the specification, whenever a part is said to "include" a component, this does not mean that it excludes other components, but rather that it may include other components, unless otherwise stated.

[0078]

[0079] As described above, one aspect of the present invention proposes an uplink transmission control method and devices therefor that take into account the characteristics of ambient IoT devices.

[0080] FIG. 3 and FIG. 4 are diagrams for explaining a method for a reader to control an uplink transmission method of ambient IoT devices in a mobile communication system supporting A-IoT according to one embodiment of the present invention.

[0081] In FIG. 3, the 'reader' is a device for securing data of A-IoT devices (210a-210n) and providing A-IoT services, and may be a base station (220) or an intermediate node (215) between the base station (220) and A-IoT devices (210a-210n). This will be described in detail with reference to FIG. 4.

[0082] Drawing reference numeral 410 of FIG. 4 illustrates a structure in which an A-IoT device (210a) is directly connected to a base station (220), and the A-IoT device (210a) responds to a query of the base station (220) and transmits data.

[0083] Meanwhile, drawing reference numeral 420 of FIG. 4 illustrates a structure in which an A-IoT device (210b) is not directly connected to a base station (220), but transmits data to the base station (220) via an intermediate medium (215).

[0084] The intermediate medium (215) may be a general portable user equipment (UE), such as a smartphone, that performs 5G communication or subsequent 6G communication. FIG. 4 illustrates a concept in which a general UE (215) is connected to a base station (220) via a Uu interface.

[0085] The UE as such an intermediate medium (215) can be connected to multiple A-IoT devices and transmit data of the A-IoT devices to the base station (220).

[0086] With regard to the description of FIG. 4, it can be generally seen that the base station (220) acts as a reader that collects data from A-IoT devices (210a, 210b). However, depending on the case / use case, the UE (215) may also act as a reader that collects data from A-IoT devices (210a, 210b).

[0087] For convenience of explanation, the following description assumes that the 'reader' corresponds to the base station (220), but is not limited thereto.

[0088]

[0089] Referring again to FIG. 3, the reader (base station (220)) can transmit a downlink signal (S310a - S310n) to the ambient IoT devices (210a - 210n) and receive a first uplink signal (S320a - S320n) from the ambient IoT devices (210a - 210n).

[0090] In such an A-IoT system, the downlink is proposed to not perform channel measurement, flow control, or FEC. On the other hand, in one embodiment of the present invention, the uplink signal is proposed to selectively perform one or more of channel measurement, flow control, and FEC (S330).

[0091] In an A-IoT system using passive UEs, the downlink signal is sufficiently strong that it is efficient not to increase the complexity of the A-IoT devices (210a-210n) for separate channel measurement, flow control, and FEC for A-IoT service provision. However, in the case of uplink signals, especially in the case of signals transmitted in a backscattering manner as described below, it may be difficult to secure a sufficiently strong signal, and thus sufficient coverage for A-IoT service provision may not be secured.

[0092] Therefore, in this embodiment, a method is proposed to selectively perform uplink control, such as efficiently applying FEC, only to uplink signals transmitted by A-IoT devices (210a-210n).

[0093] This can also be distinguished from the RFID method that uses the same passive UE. In the RFID method, channel measurement, flow control, and FEC are not performed in the 'Interrogator to Tag' and 'Tag to Interrogator' bidirectional links. However, in the case of the A-IoT system, unlike the RFID method, sufficient coverage must be secured considering the usage example of Fig. 2, and accordingly, in this embodiment, unlike the RFID method, uplink control such as FEC is proposed to be selectively performed for uplink signals.

[0094] In LTE / NR, the transport block size varies by MCS index during flow control depending on the measurement results, but in RFID / A-IoT, it is common for fixed-size data to be transmitted at a fixed time.

[0095] In addition, the types of A-IoT devices include passive devices (device 1) with weak uplink signal strength and semi-passive devices (device 2a) with relatively strong uplink signal strength. Depending on the type of device or the service provided, FEC may not be required, just like RFID, or FEC may be required to secure coverage.

[0096]

[0097] Referring again to FIG. 3, in the A-IoT system, the A-IoT devices (210a-210n) do not perform measurements on downlink signals received from S310a-S310n. However, it is proposed that the reader (220) perform measurements on uplink signals received from the A-IoT devices (210a-210n) via S320a-S320n.

[0098] In RFID / A-IoT, performing channel measurement and flow control on an individual device is extremely difficult. In RFID, if a collision is detected in a query command, the slot counter can be adjusted using the queryAdjust command to initiate the next round. However, the format of the data transmitted by individual devices cannot be changed (e.g., by applying FEC or changing the coding rate).

[0099] Accordingly, in one embodiment of the present invention, it is proposed to control the transmission method, such as application of FEC, of ​​a subsequent second uplink signal by considering the reception status of the first uplink signal in units of groups of A-IoT devices (210a-210n) (S330).

[0100]

[0101] FIG. 5 is a diagram illustrating an example of an MCS level applicable to an uplink signal in an A-IoT system according to one embodiment of the present invention.

[0102] In the embodiment related to FIG. 3, the transmission method of the second uplink signal is controlled (S330) by considering at least one of the ratio of devices in which a CRC (Cyclic Redundancy Check) error of the first uplink signal occurs in a group of ambient IoT devices (210a to 210n), the average of the CRC error rates of each of the ambient IoT devices, or the SINR (Signal to Interference plus Noise Ration) of the first uplink signal.

[0103] For example, if the ratio of devices in which a CRC error occurs in the first uplink signal or the average of the CRC error rates of each of the ambient IoT devices is equal to or greater than a first threshold or the SINR is equal to or less than a second threshold, the method may include increasing the MCS (Modulation and Coding Scheme) level to apply FEC to the second uplink signal.

[0104] That is, when the MCS level applicable to uplink signal transmission in the A-IoT system is defined as a group coding scheme (GCS) as shown in Fig. 5, FEC is not applied to the initial transmission with GCS level 0, but in the case of an increase in error rate / insufficient reception strength as described above, the GCS value can be controlled to be increased. As FEC is applied in this way, the code rate may be lowered and the number of repetitions may be increased.

[0105] Meanwhile, the GCS level corresponding to a specific MCS level of the A-IoT uplink may be further subdivided and determined by taking into account the characteristics of the A-IoT device.

[0106]

[0107] FIG. 6 is a drawing for explaining the configuration of an A-IoT device according to one embodiment of the present invention.

[0108] A-IoT devices can have various types, and the types of A-IoT devices currently being discussed in 3GPP standardization are as follows.

[0109] Device Type 1: 1uW power consumption, energy storage, and backscattering support.

[0110] Device Type 2a: 100 uW power consumption, energy storage, backscattering, DL and / or UL amplifier support

[0111] Device Type 2b: 100 uW power consumption, energy storage, active signal generation, DL and / or UL amplifier support

[0112] Figure 6 illustrates an example of a type 1 device among the types of A-IoT devices described above.

[0113] The A-IoT device illustrated in FIG. 6 may include a matching network (510), an RF energy harvester (520: harvester), a PMU (531: Power Management Unit), and an energy storage module (532) to support an energy storage function. In brief, the RF energy harvester (520) extracts energy from a received RF signal and stores it in the energy storage module (532), thereby supporting the operation of a low-power consumption A-IoT device.

[0114] Meanwhile, for processing the signal received by DL, an RF BPF (541: Band Pass Filter), an RF energy envelope detector (542), a BB LPF (543: BaseBand Low Pass Filter), a comparator / 1-bit ADC (552), and a clock generator (551) may be included.

[0115] It is currently under discussion whether the frequency band of the DL signal of the A-IoT device will be used fixedly or variably, and accordingly, the RF BPF (541) is indicated by a dotted line in the structure of Fig. 6.

[0116] Processing of the received DL signal and generation of the UL signal can be performed by the BB logic (553) including a decoder, a controller, and an encoder, as illustrated in FIG. 6. The necessary information is stored by the memory (560), and the stored information can be reused by the BB logic (553).

[0117] The UL signal transmission of an A-IoT device can be transmitted through a backscatter modulator (570). Roughly speaking, an A-IoT device with a simple, low-power transmission structure transmits a UL signal by backscatter-ing the signal, and can perform line coding by adjusting the impedance to Z1 or Z2 as illustrated in FIG. 6.

[0118]

[0119] Line codings applicable to UL signals transmitted by A-IoT devices include Manchester, FM0, and Miller coding, and performance verification for each line coding method is being discussed.

[0120] If sufficient coverage can be secured for the uplink signal of the A-IoT system through line coding, a separate FEC may not be necessary. Therefore, in one embodiment of the present invention, it is proposed to selectively perform one or more of channel measurement, flow control, and FEC depending on whether the required coverage can be secured through line coding applied to the uplink signal. Here, flow control may include transmitting repeated messages with line coding.

[0121] As an example of the present invention, the reader can determine whether to apply FEC to the D2R signal transmitted by the A-IoT device to the reader and notify the A-IoT device. That is, when starting an inventory procedure, the reader can determine in advance whether to apply FEC and notify the A-IoT device, and accordingly, the A-IoT device can operate to apply or not apply FEC from the first message (msg1).

[0122] Accordingly, the reader according to the present embodiment proposes to inform the A-IoT device of whether D2R FEC is applied when transmitting an inventory / query message in a manner similar to informing information about MCS. The A-IoT devices receiving this may selectively apply FEC when transmitting a D2R signal to the reader based on the information on whether D2R FEC is applied.

[0123]

[0124] As another example, in addition to the GCS level regulation proposed with respect to FIG. 5, when the ratio of devices in which a CRC error occurs in the first uplink signal per group of A-IoT devices, the average of the CRC error rates of each of the A-IoT devices is equal to or greater than a first threshold, or the SINR of the first uplink signal is equal to or less than a second threshold, the number of chips per symbol may be increased when applying line coding, and accordingly, an item for adjusting the number of chips per symbol in line coding may be added to the GCS value table of FIG. 5.

[0125]

[0126] Meanwhile, as described above, controlling the transmission method of the second uplink signal according to the reception status of the first uplink signal may be controlled per uplink signal transmission round or in the middle of a round.

[0127]

[0128] Round unit control

[0129] FIG. 7 is a diagram for explaining a method of performing uplink signal control in round units according to one embodiment of the present invention.

[0130] When a reader (e.g., a base station (220)) transmits an initial query message (Query message; 610) to A-IoT devices (210), it may transmit a value indicating the number of time resources (e.g., slots) to which each A-IoT device (210) can connect. Hereinafter, the number of such time resources is referred to as Q.

[0131] A-IoT devices are based on the corresponding Q value. Q - By setting a random function of 1, data can be transmitted as a query response (620) to a time resource (slot) corresponding to the value.

[0132] The above Q value can be changed independently by considering the number of A-IoT devices (210) and / or the influence of interference at the base station (220).

[0133] In one embodiment of the present invention, controlling the transmission method of the second uplink signal in the embodiment related to FIG. 3 may correspond to determining the CRC error rate, SINR, etc. of uplink signals received within one period (T: 630) from the downlink transmission of the query message (610) until the reception of the query response (620) as the first uplink signal, and determining the MCS (GCS) level including whether to apply FEC to the second uplink signal to be received in the next period (T) based on this.

[0134] To this end, after the end of the cycle (T: 630) for receiving a question and answer (620), the reader (220) can transmit a command to increase the MCS (GCS) level to the A-IoT device (210) through a SelectCommand message (640), etc.

[0135]

[0136] Control within the round

[0137] FIG. 8 is a diagram for explaining a method of performing uplink signal control within a round according to one embodiment of the present invention.

[0138] Similarly to FIG. 7, when a reader (e.g., a base station (220)) transmits an initial query message (Query message; 610) to A-IoT devices (210), it may transmit a value indicating the number of time resources (e.g., slots) to which each A-IoT device (210) can connect, and accordingly, a response period (T: 630) may be specified.

[0139] However, in this embodiment, unlike the case of FIG. 7, even before the response period (T) ends, if it is determined that there is a problem with the CRC error rate / SINR performance of the first uplink signals received from the A-IoT device (210), it is proposed to control the uplink transmission method of the A-IoT device (210) through a message such as a query adjustment (QueryAdjust) message (710) even before the response period (T: 630) ends.

[0140] In this case, in the embodiment of FIG. 3, both the first uplink signal and the second uplink signal are signals received within a response period (630) to the query message (610) of the base station (220), but the second uplink signal may correspond to an uplink signal after the MCS (GCS) level is increased through the query adjustment message (710).

[0141]

[0142] Response based on device status

[0143] Meanwhile, in one embodiment of the present invention, it is proposed to control the method of subsequent uplink signal transmission (e.g., retransmission) by differentiating it according to the uplink signal transmission status of a plurality of A-IoT devices (210a-210n).

[0144] Specifically, in the embodiment of FIG. 8, the 'second uplink signal' may include a signal transmitted by an A-IoT device in a first state that failed to transmit a first uplink signal based on an MCS (GCS) level increase command of a query adjustment (710) message, and a signal retransmitted by an A-IoT device in a second state that transmitted a first uplink signal but was not successfully received by the base station (220) based on the MCS (GCS) level increase command.

[0145] Additionally, in some cases, it may be efficient for the base station (220) to selectively command retransmission depending on the status of the A-IoT devices.

[0146]

[0147] FIG. 9 is a table for defining the status of A-IoT devices according to one embodiment of the present invention.

[0148] As illustrated in Fig. 9, A-IoT devices can operate in any one of the following states: an initial state (A), a state in which a device ID has been transmitted to a reader (B), or a state in which a positive response (ACK or QueryRep) has been received from a reader (C).

[0149] When defining the status of A-IoT devices in this way, controlling the transmission method of the second uplink signal may include transmitting a message including information that specifies a response target according to the status of the A-IoT devices.

[0150] That is, in this embodiment, when performing flow control on a device group basis, if retransmission is performed without distinguishing between devices that have successfully transmitted an uplink signal and those that have failed, unnecessary retransmissions may result in increased traffic and delays. Therefore, it is desirable to perform uplink signal control by distinguishing between these. However, since A-IoT does not use ARQ, etc., it may be difficult to control whether signal transmission was successful or not on an individual device basis.

[0151] Therefore, in one embodiment of the present invention, in order to distinguish the status of A-IoT devices as shown in FIG. 9 and to distinguish the success status of uplink signal transmission for each device, it is proposed to store a status value as shown in FIG. 9 in a state flag of the device and change the status within three states according to the transmission conditions.

[0152]

[0153] Specifically, the reader can select a device group with a selection command message and, at this time, inform the reader of the initial slot size and code rate. During the process of performing an inventory round, an A-IoT device that has transmitted an uplink signal (data) to the reader can change its state from A => B, and then change its state from B => C upon receiving an ACK from the reader.

[0154] The reader can increase the slot count with a query adjustment command if a collision is detected during an inventory round.

[0155] Additionally, the reader performs uplink measurements during the inventory round process. If the SINR is low or the error rate is high, the code rate can be changed via a selection command. The selection flags in the selection command can be used to identify the A-IoT devices that should respond to the query command.

[0156] For example, a selection flag could indicate 'all devices', or 'devices except state A devices', or 'state B devices that should perform a retransmission', etc.

[0157]

[0158] Communication frequency control

[0159] As described above, in another aspect of the present invention, assuming an A-IoT device that operates without fixing the frequency, a method for controlling a communication frequency that takes into account the characteristics of the A-IoT device and devices therefor are proposed.

[0160] FIG. 10 is a diagram for explaining a method for an A-IoT device to secure frequency information to be used for communication according to one embodiment of the present invention.

[0161] Referring to FIG. 10, the A-IoT device (210) can receive a first message including a preamble and data from a reader (220, 215) via a first frequency (S1010). At this time, it is preferable that information regarding the first frequency is hard-coded into the corresponding ambient IoT device (210).

[0162] In A-IoT, A-IoT devices can have various types, but as mentioned above, it is assumed that A-IoT does not support the verification process for UE Capability like a general 5G UE.

[0163] Therefore, it is expected that the standard will be defined based on the type of A-IoT device with the lowest performance among various types of A-IoT devices. Since it is expected that ultra-low-cost A-IoT devices will not operate by switching frequencies like existing 5G UEs and using frequencies to be used for communication, it is proposed that in this embodiment, an A-IoT device (210) of a type that can variably use frequencies stores a first frequency as an initial frequency in a hard-coded manner, and performs communication by obtaining information about a second frequency, which is an actual use frequency, through a first message received from a reader (220, 215).

[0164] At this time, 'hard coding' may mean a method of fixing by recording frequency information (e.g., PRB (Physical Resource Block) information) to be used in the storage device of the A-IoT device (210) when manufacturing the device.

[0165] In this way, it is proposed that the A-IoT device (210) that has received the first message obtains second frequency information (S1020) through the preamble of the first message.

[0166] Although the message transmission method in A-IoT is still in the process of being standardized, this embodiment proposes the following message transmission method.

[0167] - The channel bandwidth is 180 kHz and uses 1 PRB.

[0168] - Do not fix the PRB index to be used for communication.

[0169] - When transmitting DL / UL, control signals and data are transmitted together, not just the control signals.

[0170] - The subcarrier spacing uses 15 kHz.

[0171]

[0172] In the method of sending control signals and data, this embodiment assumes that the control signal is transmitted in the form of a preamble before sending data, and proposes that the control signal for the second frequency described above (a PRB index to be used for communication as a specific example) be transmitted through the preamble.

[0173] The A-IoT device (210) can transmit a second message to the reader (220, 215) through the second frequency acquired through the preamble of the first message (S1030), and thereafter, can communicate with the reader (220, 215) through the second frequency.

[0174]

[0175] FIG. 11 is a drawing specifically explaining a frequency to be used by an A-IoT device according to one embodiment of the present invention.

[0176] As illustrated in FIG. 11, the bandwidth (1110) for ambient IoT may include an occupied bandwidth (1120) and a guard band surrounding it. In one embodiment of the present invention, the initial frequency (1130) corresponding to the first frequency described above is positioned within the guard band, thereby increasing bandwidth efficiency. Of course, the first frequency may be positioned within the occupied bandwidth (1120) as needed, and the present invention is not limited thereto.

[0177] Under these assumptions, the preamble of the first message transmitted by the reader (220, 215) to the A-IoT device (210) may include difference information from the first frequency (1130) to the second frequency (1140) corresponding to the PRB to be used for actual communication.

[0178] Specifically, this difference information is the frequency offset (freq) from the first frequency (1130) to the first PRB (1st PRB) of the used bandwidth (1120). offset ; 1150), and the PRB index corresponding to the second frequency (PRB i ; 1140) may be included.

[0179]

[0180] FIG. 12 is a diagram for explaining the time relationship between receiving a first message and transmitting a second message in response thereto according to one embodiment of the present invention.

[0181] As illustrated in FIG. 12, the first message may include a preamble and a data field, wherein the preamble may include a control signal indicating the second frequency information as described above. Additionally, the data may correspond to information for performing a query on the A-IoT device. This first message may be transmitted via an initial frequency (the first frequency).

[0182] Meanwhile, in the embodiment illustrated in FIG. 12, the preamble of the first message includes not only a control signal indicating the second frequency information, but also a time offset (T) for transmitting the second message. offset ; 1210) is additionally included. The A-IoT device receiving this can transmit a second message to the reader after a time offset (1210), and this second message is transmitted at a second frequency (PRB i ) can be transmitted.

[0183]

[0184] Meanwhile, the Type 1 device illustrated in FIG. 6 does not use an uplink / downlink amplifier, but as described above, Type 2a and Type 2b devices may additionally include an uplink / downlink amplifier.

[0185] Also, similar to the type 1 device illustrated in FIG. 6, the type 2a device also transmits UL signal transmission in a backscattering manner, but the type 2b device can be distinguished in that it can have a configuration in which the UL signal transmission is transmitted as an internally generated signal.

[0186] In addition, in one embodiment of the present invention, in addition to the distinction of device types as described above, it is proposed to specify that types are distinguished based on whether the usage frequency can be changed.

[0187] For example, in one embodiment of the present invention, the types of A-IoT devices can be defined as follows.

[0188] Type-based type 11uW power consumption, energy storage and backscattering function support, frequency fixed Type 2a 100uW power consumption, energy storage, backscattering, DL and / or UL amplifier support, frequency fixed Type 2b 100uW power consumption, energy storage, active signal generation, DL and / or UL amplifier support, frequency fixed Type 2c 100uW power consumption, energy storage, active signal generation, DL and / or UL amplifier support, frequency changeable

[0189]

[0190] In the example of [Table 1] above, considering the possibility that changes in the usage frequency may be restricted due to the use of backscattering in UL signal transmission, Type 1 and Type 2a newly defined an additional type that allows changes in the usage frequency in devices that use active signal generation, such as Type 2b. However, this is only an exemplary distinction and need not be limited thereto.

[0191] That is, in this embodiment, it is proposed that A-IoT device types be distinguished by (1) peak power consumption level, (2) whether or not they include an amplifier in at least one of the uplink or downlink, (3) whether or not they backscatter or internally generate the uplink transmission signal, and (4) whether or not they can vary the usage frequency, and various combinations of device types can be specified as long as these criteria are satisfied.

[0192] [Table 2] below is an example of another type regulation.

[0193] Type Standard Type 1a 1uW power consumption, energy storage and backscattering function support, fixed frequency of use Type 1b 1uW power consumption, energy storage and backscattering function support, frequency of use can be changed Type 2a 100 uW power consumption, energy storage, backscattering, DL and / or UL amplifier support, frequency of use can be fixed Type 2b 100 uW power consumption, energy storage, backscattering, DL and / or UL amplifier support, frequency of use can be changed Type 2c 100 uW power consumption, energy storage, active signal generation, DL and / or UL amplifier support, frequency of use can be fixed Type 2d 100 uW power consumption, energy storage, active signal generation, DL and / or UL amplifier support, frequency of use can be changed

[0194]

[0195] FIG. 13 and FIG. 14 are diagrams for explaining a method for periodically managing the usage frequency of an A-IoT device according to one embodiment of the present invention.

[0196] First, referring to FIG. 13, the operations corresponding to the drawing symbols S1010 to S1030 are the same as the embodiment of FIG. 10. However, in the present embodiment, if a predetermined period (T2) has elapsed from the time of receiving the first message, or if a predetermined period (T1) has elapsed from the time of transmitting the second message via the second frequency, the A-IoT device (210) monitors the first frequency again (S1310) and obtains information on a frequency (hereinafter, “third frequency”) to be used thereafter through a message (hereinafter, “third message”) received from the reader (220, 215) (S1320).

[0197] That is, in a mobile communication system supporting A-IoT, there may be a need to change the frequency of use due to changes in the number / arrangement of A-IoT devices providing services, and for this purpose, in this embodiment, it is proposed to configure the initial frequency (first frequency) to be monitored again after a predetermined period (T) (e.g., T1 or T2 in FIG. 13) has elapsed, so as to monitor changes in the frequency of use. The 'first frequency' may be referred to as a different term, such as a 'base frequency', rather than the 'initial frequency', in that it is a frequency that repeatedly checks the frequency of use in units of predetermined periods.

[0198] In the example of FIG. 13, the duration of T1 may have an advantage in terms of identifying a change in usage frequency based on the duration that the A-IoT device has used the second frequency, but may have a disadvantage in that it is complicated for the reader (220) to manage different second frequency usage durations of all A-IoT devices.

[0199] In contrast, the period of T2 is based on the transmission of the first message of the reader (220), which has the advantage of allowing for a simple operation to be defined in a manner that periodically defines the transmission of the first message (or the third message following it) of the reader (220). To this end, the first message (or the third message following it) may additionally include information regarding the T2 period.

[0200] FIG. 14 is a diagram that summarizes the operation of the embodiment described above with respect to FIG. 13 in the form of a flowchart in a situation where the base station operates as a reader.

[0201] First, the base station (220) can transmit a first message including a preamble and a query message at regular intervals (T) in a first frequency band corresponding to an initial frequency (S910).

[0202] The A-IoT device (210) can confirm the first frequency and receive the preamble and query message of the first message (S920). Accordingly, the A-IoT device (210) can receive the second frequency information, i.e., the PRB location to be used for communication, through the preamble of the first message. i ) information can be obtained (S930). After that, the A-IoT device (210) transmits the second frequency (PRB i ) can transmit a second message in reply to the query message (S940).

[0203] The A-IoT device (210) according to the present embodiment proposes to determine whether a predetermined period (T) has elapsed after changing the communication frequency to PRBi (S950). As described above with respect to FIG. 13, determining whether the predetermined period (T) has elapsed may be replaced by determining whether the predetermined period (T) has elapsed after receiving the first message.

[0204] If the specified period (T) has not elapsed, the A-IoT device (210) transmits the second frequency (PRB i ) can continue communication (S960). However, if a predetermined period (T) has elapsed, the A-IoT device (210) can monitor the first frequency again and repeat the procedure of obtaining information on the frequency that can be used thereafter.

[0205]

[0206] Figure 15 illustrates a wireless device to which the present technology can be applied.

[0207] Referring to FIG. 15, the first wireless device (100) and the second wireless device (200) can transmit and receive wireless signals via various wireless access technologies (e.g., LTE, NR). Here, the first wireless device (100) and the second wireless device (200) can correspond to the A-IoT devices (210a-210n) and readers (215, 220) of FIG. 3, respectively.

[0208] A first wireless device (100) includes one or more processors (102) and one or more memories (104), and may further include one or more transceivers (106) and / or one or more antennas (108). The processor (102) controls the memories (104) and / or the transceivers (106), and may be configured to implement the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed in this document. For example, the processor (102) may process information in the memory (104) to generate first information / signal, and then transmit a wireless signal including the first information / signal via the transceiver (106). In addition, the processor (102) may receive a wireless signal including second information / signal via the transceiver (106), and then store information obtained from signal processing of the second information / signal in the memory (104). The memory (104) may be connected to the processor (102) and may store various information related to the operation of the processor (102). For example, the memory (104) may perform some or all of the processes controlled by the processor (102), or may store software code including commands for performing the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in this document. Here, the processor (102) and the memory (104) may be part of a communication modem / circuit / chip designed to implement a wireless communication technology (e.g., LTE E-UTRA, 5G NR). The transceiver (106) may be connected to the processor (102) and may transmit and / or receive wireless signals via one or more antennas (108). The transceiver (106) may include a transmitter and / or a receiver. The transceiver (106) may be used interchangeably with an RF (Radio Frequency) unit. In the present invention, a wireless device may also mean a communication modem / circuit / chip.

[0209] The second wireless device (200) includes one or more processors (202), one or more memories (204), and may further include one or more transceivers (206) and / or one or more antennas (208). The processor (202) controls the memories (204) and / or the transceivers (206), and may be configured to implement the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed in this document. For example, the processor (202) may process information in the memory (204) to generate third information / signals, and then transmit a wireless signal including the third information / signals via the transceivers (206). Furthermore, the processor (202) may receive a wireless signal including fourth information / signals via the transceivers (206), and then store information obtained from signal processing of the fourth information / signals in the memory (204). The memory (204) may be connected to the processor (202) and may store various information related to the operation of the processor (202). For example, the memory (204) may store software code including commands for performing some or all of the processes controlled by the processor (202) or for performing the descriptions, functions, procedures, proposals, methods and / or operation flowcharts disclosed in this document. Here, the processor (202) and the memory (204) may be part of a communication modem / circuit / chip designed to implement a wireless communication technology (e.g., LTE E-UTRA, 5G NR). The transceiver (206) may be connected to the processor (202) and may transmit and / or receive wireless signals via one or more antennas (208). The transceiver (206) may include a transmitter and / or a receiver. The transceiver (206) may be used interchangeably with an RF unit. In the present invention, a wireless device may also mean a communication modem / circuit / chip.

[0210] Hereinafter, the hardware elements of the wireless device (100, 200) will be described in more detail. Although not limited thereto, one or more protocol layers may be implemented by one or more processors (102, 202). For example, one or more processors (102, 202) may implement one or more layers (e.g., functional layers such as PHY, MAC, RLC, PDCP, RRC, SDAP). One or more processors (102, 202) may generate one or more Protocol Data Units (PDUs) and / or one or more Service Data Units (SDUs) according to the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in this document. One or more processors (102, 202) may generate messages, control information, data, or information according to the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in this document. One or more processors (102, 202) can generate signals (e.g., baseband signals) including PDUs, SDUs, messages, control information, data or information according to the functions, procedures, proposals and / or methods disclosed herein, and provide the signals to one or more transceivers (106, 206). One or more processors (102, 202) can receive signals (e.g., baseband signals) from one or more transceivers (106, 206) and obtain PDUs, SDUs, messages, control information, data or information according to the descriptions, functions, procedures, proposals, methods and / or operational flowcharts disclosed herein.

[0211] One or more processors (102, 202) may be referred to as a controller, a microcontroller, a microprocessor, or a microcomputer. One or more processors (102, 202) may be implemented by hardware, firmware, software, or a combination thereof. For example, one or more Application Specific Integrated Circuits (ASICs), one or more Digital Signal Processors (DSPs), one or more Digital Signal Processing Devices (DSPDs), one or more Programmable Logic Devices (PLDs), or one or more Field Programmable Gate Arrays (FPGAs) may be included in one or more processors (102, 202). The descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed in this document may be implemented using firmware or software, and the firmware or software may be implemented to include modules, procedures, functions, etc. The descriptions, functions, procedures, suggestions, methods and / or operation flowcharts disclosed in this document may be implemented using firmware or software configured to perform one or more processors (102, 202) or stored in one or more memories (104, 204) and executed by one or more processors (102, 202). The descriptions, functions, procedures, suggestions, methods and / or operation flowcharts disclosed in this document may be implemented using firmware or software in the form of codes, instructions and / or sets of instructions.

[0212] One or more memories (104, 204) may be coupled to one or more processors (102, 202) and may store various forms of data, signals, messages, information, programs, codes, instructions, and / or commands. The one or more memories (104, 204) may be configured as ROM, RAM, EPROM, flash memory, hard drives, registers, cache memory, computer-readable storage media, and / or combinations thereof. The one or more memories (104, 204) may be located internally and / or externally to the one or more processors (102, 202). Additionally, the one or more memories (104, 204) may be coupled to the one or more processors (102, 202) via various technologies, such as wired or wireless connections.

[0213] One or more transceivers (106, 206) can transmit user data, control information, wireless signals / channels, etc., as mentioned in the methods and / or flowcharts of this document, to one or more other devices. One or more transceivers (106, 206) can receive user data, control information, wireless signals / channels, etc., as mentioned in the descriptions, functions, procedures, proposals, methods and / or flowcharts of this document, from one or more other devices. For example, one or more transceivers (106, 206) can be connected to one or more processors (102, 202) and can transmit and receive wireless signals. For example, one or more processors (102, 202) can control one or more transceivers (106, 206) to transmit user data, control information, or wireless signals to one or more other devices. Additionally, one or more processors (102, 202) may control one or more transceivers (106, 206) to receive user data, control information, or wireless signals from one or more other devices. Additionally, one or more transceivers (106, 206) may be coupled to one or more antennas (108, 208), and one or more transceivers (106, 206) may be configured to transmit and receive user data, control information, wireless signals / channels, or the like, as referred to in the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed herein, via one or more antennas (108, 208). In this document, one or more antennas may be multiple physical antennas or multiple logical antennas (e.g., antenna ports). One or more transceivers (106, 206) can convert received user data, control information, wireless signals / channels, etc. from RF band signals to baseband signals in order to process the received user data, control information, wireless signals / channels, etc. using one or more processors (102, 202).One or more transceivers (106, 206) may convert user data, control information, wireless signals / channels, etc. processed by one or more processors (102, 202) from baseband signals to RF band signals. For this purpose, one or more transceivers (106, 206) may include an (analog) oscillator and / or filter.

[0214]

[0215] The detailed description of the preferred embodiments of the present invention disclosed above has been provided to enable those skilled in the art to implement and practice the present invention. While the above description has been made with reference to preferred embodiments of the present invention, those skilled in the art will appreciate that various modifications and variations can be made to the present invention without departing from the scope of the present invention. For example, those skilled in the art can utilize the individual components described in the above-described embodiments in combination with each other.

[0216] Accordingly, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0217] The uplink transmission control method and devices therefor, which take into account the characteristics of ambient IoT devices according to the embodiments of the present invention as described above, are suitable for use in a 3GPP-based mobile communication environment, but as described above, they can also be widely utilized in communication methods other than 3GPP to efficiently secure coverage performance in an ambient IoT environment.

Claims

1. In a mobile communication system supporting Ambient IoT (Internet of Things), a method for controlling the uplink transmission method of ambient IoT devices by a reader is provided. Transmitting downlink signals to the above ambient IoT devices; Receives a first uplink signal from the above ambient IoT devices; and Including controlling the transmission method of the second uplink signal following the first uplink signal of the above ambient IoT devices, The above downlink signal does not perform channel measurement, flow control, and FEC (Forward Error Correction). The first and second uplink signals selectively perform one or more of channel measurement, flow control, and FEC. A method for controlling an uplink transmission method, wherein controlling a transmission method of the second uplink signal includes controlling the reception status of the first uplink signal by group of ambient IoT devices.

2. In paragraph 1, Controlling the transmission method of the above second uplink signal is as follows: An uplink transmission method comprising controlling by considering at least one of a ratio of devices in which a CRC (Cyclic Redundancy Check) error of the first uplink signal occurs in a group unit of the ambient IoT devices, an average of the CRC error rates of each of the ambient IoT devices, or a SINR (Signal to Interference plus Noise Ration) of the first uplink signal.

3. In paragraph 2, An uplink transmission method comprising increasing an MCS (Modulation and Coding Scheme) level to apply FEC to the second uplink signal when a ratio of devices in which a CRC error of the first uplink signal occurs or an average of the CRC error rates of each of the ambient IoT devices is equal to or greater than a first threshold or when the SINR is equal to or less than a second threshold.

4. In paragraph 1, The above downlink signal is, Contains information indicating whether FEC is applied to the uplink signal. The first and second uplink signals are selectively applied with FEC based on information indicating whether or not the FEC is applied. Method for controlling uplink transmission method.

5. In paragraph 1, An uplink transmission method for controlling the first and second uplink signals, wherein the first and second uplink signals selectively perform one or more of channel measurement, flow control, and FEC depending on whether the required coverage can be secured by line coding applied to the first and second uplink signals.

6. In paragraph 5, Controlling the transmission method of the above second uplink signal is as follows: An uplink transmission method comprising increasing the number of chips per symbol when applying line coding, when the ratio of devices in which a CRC (Cyclic Redundancy Check) error of the first uplink signal occurs in a group of the ambient IoT devices, when the average of the CRC error rates of each of the ambient IoT devices is equal to or greater than a first threshold, or when the SINR of the first uplink signal is equal to or less than a second threshold.

7. In paragraph 3, Additionally comprising transmitting a first query message to the above ambient IoT devices, A method for controlling an uplink transmission method, wherein the first uplink signal is received as a response within a response period for the first query message.

8. In paragraph 7, Increasing the above MCS level, An uplink transmission method further comprising transmitting a message including a command for instructing the ambient IoT devices to increase the MCS level within the response period.

9. In paragraph 8, The above second uplink signal is, A signal transmitted by an ambient IoT device in a first state that has failed to transmit the first uplink signal based on the MCS level increase command, and An uplink transmission method comprising a signal retransmitted based on the MCS level increase command by an ambient IoT device in a second state that transmitted the first uplink signal but was not successfully received by the reader.

10. In paragraph 7, Increasing the above MCS level, An uplink transmission method control method, comprising transmitting a command indicating an increase in the MCS level through the second query message when transmitting a second query message to the ambient IoT devices after the response period ends.

11. In paragraph 10, An uplink transmission method control method, wherein the second uplink signal is received as a response within the response period of the second query message.

12. In paragraph 1, The above ambient IoT devices are: Initial state, The device ID has been transmitted to the above reader, or A positive response has been received from the above reader A method for controlling an uplink transmission method, which operates in one of the following states.

13. In paragraph 12, Controlling the transmission method of the above second uplink signal is as follows: An uplink transmission method control method comprising transmitting a message including information specifying a response target according to the status of each of the above ambient IoT devices.

14. In paragraph 1, Transmitting a first message including a preamble and data to the ambient IoT device through a first frequency hardcoded into the ambient IoT device, The preamble of the first message includes second frequency information; and Receiving a second message from the ambient IoT device via the second frequency, Method for controlling uplink transmission method.

15. In paragraph 14, The above first frequency is located in the guard band among the bandwidths for the ambient IoT of the mobile communication system. Method for controlling uplink transmission method.

16. In paragraph 14, The preamble of the first message includes difference information from the first frequency to the second frequency. Method for controlling uplink transmission method.

17. In paragraph 16, The above difference information is, A frequency offset from the first frequency to the first PRB (Physical Resource Block) of the occupied bandwidth among the ambient IoT bandwidths of the mobile communication system, and including a PRB index corresponding to the second frequency, Method for controlling uplink transmission method.

18. In a mobile communication system supporting Ambient IoT (Internet of Things), a method for an Ambient IoT device to communicate with a reader, Receive a downlink signal from the above reader; Transmitting a first uplink signal to the above reader; Receive a message from the reader for controlling a transmission method of a second uplink signal subsequent to the first uplink signal; Including transmitting the second uplink signal to the reader according to the above message, The above downlink signal does not perform channel measurement, flow control, and FEC (Forward Error Correction). The first and second uplink signals selectively perform one or more of channel measurement, flow control, and FEC. The message controlling the transmission method of the second uplink signal is: A communication method of an ambient IoT device, determined by considering the reception status of a group unit including the above ambient IoT device.

19. In a reader of a mobile communication system supporting Ambient IoT (Internet of Things), at least one processor; and At least one computer memory operably connected to said at least one processor and storing instructions that, when executed, cause said at least one processor to perform operations; The above actions are, Transmit downlink signals to ambient IoT devices; Receives a first uplink signal from the above ambient IoT devices; and Including controlling the transmission method of the second uplink signal following the first uplink signal of the above ambient IoT devices, The above downlink signal does not perform channel measurement, flow control, and FEC (Forward Error Correction). The first and second uplink signals selectively perform one or more of channel measurement, flow control, and FEC. A reader, wherein controlling the transmission method of the second uplink signal includes controlling the reception status of the first uplink signal by group of ambient IoT devices.

20. In an ambient IoT device of a mobile communication system supporting the Ambient IoT (Internet of Things), at least one processor; and At least one computer memory operably connected to said at least one processor and storing instructions that, when executed, cause said at least one processor to perform operations; The above actions are, Receive a downlink signal from a reader; Transmitting a first uplink signal to the above reader; Receive a message from the reader for controlling a transmission method of a second uplink signal subsequent to the first uplink signal; Including transmitting the second uplink signal to the reader according to the above message, The above downlink signal does not perform channel measurement, flow control, and FEC (Forward Error Correction). The first and second uplink signals selectively perform one or more of channel measurement, flow control, and FEC. The message controlling the transmission method of the second uplink signal is: An ambient IoT device determined by considering the reception status of a group unit including the above ambient IoT device.

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