Apparatus and method for configuring frequency hopping for an ambient internet of things channel

Abstract

Various aspects of the present disclosure relate to methods, apparatuses, and devices for wireless communication. A base station may determine (902) a configuration having one or more of a frequency hopping configuration associated with different tones for an external node, wherein a frequency hopping indicated by the frequency hopping configuration is associated with a frequency response of an ambient internet of things (AIoT) device, and a frequency hopping operation associated with the AIoT device, wherein the frequency hopping operation comprises applying a frequency shift to an uplink (UL) signal. The base station may also transmit (904) the configuration.

Description

APPARATUS AND METHOD FOR CONFIGURING FREQUENCY HOPPING FOR AN AMBIENT INTERNET OF THINGS CHANNELTECHNICAL FIELD

[0001] The present disclosure relates to wireless communications, and more specifically to configuring frequency hopping for an ambient internet of things (AIoT) channel.BACKGROUND

[0002] A wireless communications system may include one or multiple network communication devices, such as base stations, which may support wireless communications for one or multiple user communication devices, which may be otherwise known as user equipment (UE), or other suitable terminology. The wireless communications system may support wireless communications with one or multiple user communication devices by utilizing resources of the wireless communication system (e.g., time resources (e.g., symbols, slots, subframes, frames, or the like) or frequency resources (e.g., subcarriers, carriers, or the like). Additionally, the wireless communications system may support wireless communications across various radio access technologies including third generation (3G) radio access technology, fourth generation (4G) radio access technology, fifth generation (5G) radio access technology, among other suitable radio access technologies beyond 5G (e.g., sixth generation (6G)).SUMMARY

[0003] An article “a” before an element is unrestricted and understood to refer to “at least one” of those elements or “one or more” of those elements. The terms “a,” “at least one,” “one or more,” and “at least one of one or more” may be interchangeable. As used herein, including in the claims, “or” as used in a list of items (e.g., a list of items prefaced by a phrase such as “at least one of’ or “one or more of’ or “one or both of’) indicates an inclusive list such that, for example, a list of at least one of A, B, or C means A or B or C or AB or AC or BC or ABC (i.e., A and B and C). Also, as used herein, the phrase “based on” shall not be construed as a reference to a closed set of conditions. For example, an example step that is described as “based on condition A” may be based on both a condition A and a condition B without departing from the scopeof the present disclosure. In other words, as used herein, the phrase “based on” shall be construed in the same manner as the phrase “based at least in part on.” Further, as used herein, including in the claims, a “set” may include one or more elements.

[0004] Various aspects of the present disclosure relate to wireless communications, including improved methods and apparatuses that support AIoT device communication in a wireless communication system. A base station may determine a configuration including one or more of a frequency hopping configuration associated with different tones for an external node (e.g., a UE), wherein a frequency hopping indicated by the frequency hopping configuration is associated with a frequency response of an AIoT device, and a frequency hopping operation associated with the AIoT device, wherein the frequency hopping operation comprises applying a frequency shift to an uplink (UL) signal. The base station may also transmit the configuration.BRIEF DESCRIPTION OF THE DRAWINGS

[0005] Figure 1 illustrates an example of a wireless communications system in accordance with aspects of the present disclosure.

[0006] Figure 2 illustrates an example of a wireless network in accordance with aspects of the present disclosure.

[0007] Figure 3 illustrates an example of carrier wave (CW) tone switching in accordance with aspects of the present disclosure.

[0008] Figure 4 illustrates an example of signaling information of an applied frequency shift on an uplink (UL) payload in accordance with aspects of the present disclosure.

[0009] Figure 5 illustrates an example of signaling information of an applied frequency shift on different segments of an UL payload in accordance with aspects of the present disclosure.

[0010] Figure 6 illustrates an example of a UE in accordance with aspects of the present disclosure.

[0011] Figure 7 illustrates an example of a processor in accordance with aspects of the present disclosure.

[0012] Figure 8 illustrates an example of a network equipment (NE) in accordance with aspects of the present disclosure.

[0013] Figure 9 illustrates a flowchart of a method performed by a base station in accordance with aspects of the present disclosure.

[0014] Figure 10 illustrates a flowchart of a method performed by an AIoT device in accordance with aspects of the present disclosure.DETAILED DESCRIPTION

[0015] Various aspects of the present disclosure relate to AIoT devices in a wireless communication system. The AIoT devices may have limited transmission capabilities due to having little or no energy storage. In some implementations, an AIoT device may be configured to transmit using different CW tones using backscattering transmission, thereby overcoming some of the challenges of having little or no energy storage.

[0016] Configuring the AIoT devices with information to enable the AIoT devices to make backscattering transmissions on different tones (or frequencies) may reduce power consumption, reduce processor usage, reduce data usage, and increase overall system performance.

[0017] Aspects of the present disclosure are described in the context of a wireless communications system.

[0018] Figure 1 illustrates an example of a wireless communications system 100 in accordance with aspects of the present disclosure. The wireless communications system 100 may include one or more NE 102, one or more UE 104, and a core network (CN) 106. The wireless communications system 100 may support various radio access technologies. In some implementations, the wireless communications system 100 may be a 4G network, such as an LTE network or an LTE-Advanced (LTE-A) network. In some other implementations, the wireless communications system 100 may be a new radio (NR) network, such as a 5G network, a 5G-Advanced (5G-A) network, or a 5G ultrawideband (5G-UWB) network. In other implementations, the wireless communications system 100 may be a combination of a 4G network and a 5G network, or other suitable radio access technology including Institute of Electrical and Electronics Engineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20. The wireless communications system 100 may support radio access technologiesbeyond 5G, for example, 6G. Additionally, the wireless communications system 100 may support technologies, such as time division multiple access (TDMA), frequency division multiple access (FDMA), or code division multiple access (CDMA), etc.

[0019] The one or more NE 102 may be dispersed throughout a geographic region to form the wireless communications system 100. One or more of the NE 102 described herein may be or include or may be referred to as a network node, a base station, a network element, a network function, a network entity, a radio access network (RAN), a NodeB, an eNodeB (eNB), a next-generation NodeB (gNB), or other suitable terminology. An NE 102 and a UE 104 may communicate via a communication link, which may be a wireless or wired connection. For example, an NE 102 and a UE 104 may perform wireless communication (e.g., receive signaling, transmit signaling) over a Uu interface.

[0020] An NE 102 may provide a geographic coverage area for which the NE 102 may support services for one or more UEs 104 within the geographic coverage area. For example, an NE 102 and a UE 104 may support wireless communication of signals related to services (e.g., voice, video, packet data, messaging, broadcast, etc.) according to one or multiple radio access technologies. In some implementations, an NE 102 may be moveable, for example, a satellite associated with an NTN. In some implementations, different geographic coverage areas associated with the same or different radio access technologies may overlap, but the different geographic coverage areas may be associated with different NE 102.

[0021] The one or more UE 104 may be dispersed throughout a geographic region of the wireless communications system 100. A UE 104 may include or may be referred to as a remote unit, a mobile device, a wireless device, a remote device, a subscriber device, a transmitter device, a receiver device, or some other suitable terminology. In some implementations, the UE 104 may be referred to as a unit, a station, a terminal, or a client, among other examples. Additionally, or alternatively, the UE 104 may be referred to as an Intemet-of-Things (loT) device, an Intemet-of-Everything (loE) device, or machine-type communication (MTC) device, among other examples.

[0022] A UE 104 may be able to support wireless communication directly with other UEs 104 over a communication link. For example, a UE 104 may support wireless communication directly with another UE 104 over a device-to-device (D2D)communication link. In some implementations, such as vehicle-to-vehicle (V2V) deployments, vehicle-to-everything (V2X) deployments, or cellular-V2X deployments, the communication link may be referred to as a sidelink. For example, a UE 104 may support wireless communication directly with another UE 104 over a UE-to-UE interface (PC5 interface).

[0023] An NE 102 may support communications with the CN 106, or with another NE 102, or both. For example, an NE 102 may interface with other NE 102 or the CN 106 through one or more backhaul links (e.g., SI, N2, N2, or network interface). In some implementations, the NE 102 may communicate with each other directly. In some other implementations, the NE 102 may communicate with each other or indirectly (e.g., via the CN 106. In some implementations, one or more NE 102 may include subcomponents, such as an access network entity, which may be an example of an access node controller (ANC). An ANC may communicate with the one or more UEs 104 through one or more other access network transmission entities, which may be referred to as a radio heads, smart radio heads, or transmission -reception points (TRPs).

[0024] The CN 106 may support user authentication, access authorization, tracking, connectivity, and other access, routing, or mobility functions. The CN 106 may be an evolved packet core (EPC), or a 5G core (5GC), which may include a control plane entity that manages access and mobility (e.g., a mobility management entity (MME), an access and mobility management functions (AMF)) and a user plane entity that routes packets or interconnects to external networks (e.g., a serving gateway (S-GW), a Packet Data Network (PDN) gateway (P-GW), or a user plane function (UPF)). In some implementations, the control plane entity may manage non-access stratum (NAS) functions, such as mobility, authentication, and bearer management (e.g., data bearers, signal bearers, etc.) for the one or more UEs 104 served by the one or more NE 102 associated with the CN 106.

[0025] The CN 106 may communicate with a packet data network over one or more backhaul links (e.g., via an SI, N2, N2, or another network interface). The packet data network may include an application server. In some implementations, one or more UEs 104 may communicate with the application server. A UE 104 may establish a session (e.g., a protocol data unit (PDU) session, or the like) with the CN 106 via an NE 102. The CN 106 may route traffic (e.g., control information, data, and the like) between theUE 104 and the application server using the established session (e.g., the established PDU session). The PDU session may be an example of a logical connection between the UE 104 and the CN 106 (e.g., one or more network functions of the CN 106).

[0026] In the wireless communications system 100, the NEs 102 and the UEs 104 may use resources of the wireless communications system 100 (e.g., time resources (e.g., symbols, slots, subframes, frames, or the like) or frequency resources (e.g., subcarriers, carriers)) to perform various operations (e.g., wireless communications). In some implementations, the NEs 102 and the UEs 104 may support different resource structures. For example, the NEs 102 and the UEs 104 may support different frame structures. In some implementations, such as in 4G, the NEs 102 and the UEs 104 may support a single frame structure. In some other implementations, such as in 5G and among other suitable radio access technologies, the NEs 102 and the UEs 104 may support various frame structures (i.e., multiple frame structures). The NEs 102 and the UEs 104 may support various frame structures based on one or more numerologies.

[0027] One or more numerologies may be supported in the wireless communications system 100, and a numerology may include a subcarrier spacing and a cyclic prefix. A first numerology (e.g., jU=O) may be associated with a first subcarrier spacing (e.g., 15 kHz) and a normal cyclic prefix. In some implementations, the first numerology (e.g., jU=O) associated with the first subcarrier spacing (e.g., 15 kHz) may utilize one slot per subframe. A second numerology (e.g., ^=1) may be associated with a second subcarrier spacing (e.g., 30 kHz) and a normal cyclic prefix. A third numerology (e.g., ^=2) may be associated with a third subcarrier spacing (e.g., 60 kHz) and a normal cyclic prefix or an extended cyclic prefix. A fourth numerology (e.g., ju=3) may be associated with a fourth subcarrier spacing (e.g., 120 kHz) and a normal cyclic prefix. A fifth numerology (e.g., ^=4) may be associated with a fifth subcarrier spacing (e.g., 240 kHz) and a normal cyclic prefix.

[0028] A time interval of a resource (e.g., a communication resource) may be organized according to frames (also referred to as radio frames). Each frame may have a duration, for example, a 10 millisecond (ms) duration. In some implementations, each frame may include multiple subframes. For example, each frame may include 10 subframes, and each subframe may have a duration, for example, a 1 ms duration. Insome implementations, each frame may have the same duration. In some implementations, each subframe of a frame may have the same duration.

[0029] Additionally or alternatively, a time interval of a resource (e.g., a communication resource) may be organized according to slots. For example, a subframe may include a number (e.g., quantity) of slots. The number of slots in each subframe may also depend on the one or more numerologies supported in the wireless communications system 100. For instance, the first, second, third, fourth, and fifth numerologies (i.e., / r=0, ju=l, ju=2, ^=3, ^=4) associated with respective subcarrier spacings of 15 kHz, 30 kHz, 60 kHz, 120 kHz, and 240 kHz may utilize a single slot per subframe, two slots per subframe, four slots per subframe, eight slots per subframe, and 16 slots per subframe, respectively. Each slot may include a number (e.g., quantity) of symbols (e.g., orthogonal frequency division multiplexing (OFDM) symbols). In some implementations, the number (e.g., quantity) of slots for a subframe may depend on a numerology. For a normal cyclic prefix, a slot may include 14 symbols. For an extended cyclic prefix (e.g., applicable for 60 kHz subcarrier spacing), a slot may include 12 symbols. The relationship between the number of symbols per slot, the number of slots per subframe, and the number of slots per frame for a normal cyclic prefix and an extended cyclic prefix may depend on a numerology. It should be understood that reference to a first numerology (e.g., jU=O) associated with a first subcarrier spacing (e.g., 15 kHz) may be used interchangeably between subframes and slots.

[0030] In the wireless communications system 100, an electromagnetic (EM) spectrum may be split, based on frequency or wavelength, into various classes, frequency bands, frequency channels, etc. By way of example, the wireless communications system 100 may support one or multiple operating frequency bands, such as frequency range designations FR1 (410 MHz - 7.125 GHz), FR2 (24.25 GHz - 52.6 GHz), FR3 (7.125 GHz - 24.25 GHz), FR4 (52.6 GHz - 114.25 GHz), FR4a or FR4-1 (52.6 GHz - 71 GHz), and FR5 (114.25 GHz - 300 GHz). In some implementations, the NEs 102 and the UEs 104 may perform wireless communications over one or more of the operating frequency bands. In some implementations, FR1 may be used by the NEs 102 and the UEs 104, among other equipment or devices for cellular communications traffic (e.g., control information, data). In some implementations, FR2 may be used by the NEs 102 and the UEs 104, among other equipment or devices for short-range, high data rate capabilities.

[0031] FR1 may be associated with one or multiple numerologies (e.g., at least three numerologies). For example, FR1 may be associated with a first numerology (e.g., ^=0), which includes 15 kHz subcarrier spacing; a second numerology (e.g., ^=1), which includes 30 kHz subcarrier spacing; and a third numerology (e.g., ^=2), which includes 60 kHz subcarrier spacing. FR2 may be associated with one or multiple numerologies (e.g., at least 2 numerologies). For example, FR2 may be associated with a third numerology (e.g., ^=2), which includes 60 kHz subcarrier spacing; and a fourth numerology (e.g., jU=3), which includes 120 kHz subcarrier spacing.

[0032] Certain loT devices may consume very low power and may rely on harvesting energy. Moreover, an loT device may be considered an ambient loT device such as one or more of the following loT devices: device 1 which has no energy storage and no independent signal generation (e.g., it uses backscattering transmission), device 2 which has energy storage and no independent signal generation (e.g., it uses backscattering transmission) - use of stored energy may be for amplification of reflected signals, and / or device 3 which has energy storage and independent signal generation (e.g., includes an active RF component for transmission).

[0033] A range and / or coverage of a communication link between a base station (BS) and an AIoT device may be reduced with distance, channel selectivity, mobility, and / or an interference level at the BS. Because a channel between the AIoT device and the BS cannot be estimated, channel selectivity may be a major issue in UL especially if a single tone is used for a carrier wave. In some examples found herein, there may be methods for coping with frequency selectivity by configuring frequency hopping for an UL channel between the AIoT device and the BS.

[0034] Figure 2 illustrates an example of a wireless network 200 in accordance with aspects of the present disclosure. The wireless network 200 includes a NE 102-a, a UE 104-a, and an AIoT device 202. The NE 102-a may transmit configuration information and / or may control TX power for a carrier wave by communication with the UE 104-a (e.g., operating as an emitter). The UE 104-a may transmit the carrier wave to the AIoT device 202. Moreover, the NE 102-a may transmit AIoT downlink information to the AIoT device 202, and the AIoT device 202 may transmit a backscattering response to the NE 102-a.

[0035] In some systems, loT may be used for a variety of different applications. More loT devices may be interconnected for improving productivity efficiency and increasing comforts of life. Further reduction of size, complexity, and power consumption of loT devices may enable a deployment of tens or even hundreds of billions of loT devices for various applications and may provide added value across an entire value chain. It may not be possible to power all the loT devices with batteries that need to be replaced or recharged manually. The use of such batteries may lead to high maintenance costs, serious environmental issues, and safety hazards for some configurations (e.g., wireless sensors in electric power and petroleum industries).

[0036] Most of the existing wireless communication devices may be powered by batteries that need to be replaced or recharged manually. The automation and digitalization of various industries may result in new markets using loT technologies that support battery-less devices with no energy storage capability or devices with energy storage that do not have batteries that need to be replaced or recharged manually. The form factor of such devices may be small to meet the requirements of the application.

[0037] Certain devices are either battery-less or have limited energy storage capability (e.g., using a capacitor) and energy is provided to these devices by harvesting radio waves, light, motion, heat, or any other suitable power source.

[0038] Because of the limited size and complexity required by practical applications for battery-less devices with no energy storage capability or devices with limited energy storage that do not need to be replaced or recharged manually, an output power of an energy harvester may be from IpW to a few hundreds of pW. Existing cellular devices may not work well with energy harvesting due to their peak power consumption of higher than lOmW.

[0039] One application for AIoT devices may be in systems that presently use barcodes and radio frequency identifiers (RFIDs). As may be appreciated, barcodes and RFIDs have ultra-low complexity and a small form factor. However, the limited reading range of a few meters usually requires handheld scanning which leads to labor intensive and time-consuming operations, or RFID portals and / or gates which leads to costly deployment. Moreover, the lack of interference management scheme may result in severe interference between RFID readers and capacity problems, especially with densedeployment. It is hard to support a large-scale network with seamless coverage usingRFID.

[0040] AIoT technology may provide complexity and power consumption orders of magnitude lower than the existing technologies and may address systems that cannot otherwise be fulfilled based on existing technologies. Moreover, AIoT technologies may rely on ultra-low complexity devices with ultra-low power consumption for very-low end loT applications.

[0041] Moreover, AIoT technologies may enable devices having one or more of the following characteristics:

[0042] A) ~1 pW peak power consumption, has energy storage, initial sampling frequency offset (SFO) up to 10X ppm, neither DL nor UL amplification in the device. The device’s UL transmission is backscattered on a carrier wave provided externally.

[0043] B) < a few hundred pW peak power consumption 1, has energy storage, initial sampling frequency offset (SFO) up to 10X ppm, both DL and / or UL amplification in the device. The device’s UL transmission may be generated internally by the device, or be backscattered on a carrier wave provided externally.

[0044] C) a maximum coverage distance of 10-50 m with indoor devices.

[0045] D) With the UE as an intermediate node under NW control, there may be no RRC states, no mobility (e.g., at least no cell selection / re-selection -like functions), no HARQ, no ARQ, and so forth.

[0046] Deployment scenarios for AIoT devices may have the following characteristics:

[0047] A) Base station and coexistence characteristics: Micro-cell, co-site

[0048] B) With a UE as an intermediate node under network control - base station and coexistence characteristics: Macro-cell, co-site. The location of intermediate node is indoor.

[0049] C) FR1 licensed spectrum in FDD.

[0050] D) Spectrum deployment in-band to NR, in guard-band to LTE / NR, and / or in standalone bands.

[0051] E) Traffic types device oriented (DO)-DTT, DT, with focus on rUCl (indoor inventory) and rUC4 (indoor command).

[0052] Transmission from AIoT devices (including backscattering when used) may occur at least in an UL spectrum.

[0053] In a first embodiment, a BS configures carrier wave nodes for frequency hopping of a physical device to reader channel (PDRCH).

[0054] Figure 3 illustrates an example 300 of CW tone switching in accordance with aspects of the present disclosure. The example 300 includes a transmitted CW 302 and generated UL frames 304 to be transmitted based on the transmitted CW 302 over a time t and frequency f. The transmitted CW 302 includes a first tone 306, a second tone 308, and athird tone 310. As discussed herein, the second tone 308 (or another tone) may be transmitted until a CW tone switch 312, then the first tone 306 (or another tone) may be transmitted until a CW tone switch 314, after which the third tone 310 (or another tone) may be transmitted. The different portions of the generated UL frames 304 correspond to one of each of the first tone 306, the second tone 308, and the third tone 310, as illustrated.

[0055] According to the first embodiment, the BS may send a configuration to carrier wave external nodes for frequency hopping of the carrier wave tone (e.g., carrier frequency, first tone 306, second tone 308, third tone 310) transmitted to an AIoT device thereby indirectly hopping the backscattering of UL data (e.g., PDRCH). To enhance the performance of PDRCH and to avoid the frequency selectivity of the channel between the device and BS especially if a single-tone carrier wave is used, the BS sends an indication to the carrier wave node to switch (e.g., CW tone switch 312, CW tone switch 314) between different tones within the AIoT frequency response at different time resources so that the UL signal is backscattered with hopping at different frequencies as shown in Figure 3. The tones may be indicated using DL control channel and / or semi-statically sent to the external carrier wave node, where the configuration indicates some carrier frequencies and the corresponding time resources and / or length if the CW is generated using a dedicated oscillator or it indicates some sub-carrier indices of an OFDM waveform and the corresponding time resources and / or slots if OFDM transmitter is used for generating the carrier wave. The BS may send a pattern of toneswitching and / or frequency hopping repeated until the node gets an indication from the BS to stop switching or to change the pattern.

[0056] In one implementation, control information carries a switching pattern, (e.g., [2, 1, 3]) which indicates to the node to use the second tone 308 for the first time resource, the first tone 306 for the second time resource, the third tone 310 for the third time resource, and so forth. The time resource may be aligned with the UL frame if the UL frame size is known to the BS; otherwise, it is aligned with UL slot boundaries. In another implementation, an external carrier wave node is indicated with an index indicating a row in a pre-defined table as shown in Table 1. Each index may correspond to a certain pattern and certain time resource length.Table 1 : An example of pre-configured table for carrier wave frequency hopping

[0057] In one example, the time resources for hopping may be aligned with an UL frame boundary (e.g., each UL frame that includes a preamble, a control part, and a payload is backscattered on a certain CW tone as shown in figure 3).

[0058] In another example, tones are switched according to different segment portions of the UL frame (e.g., preamble and control are backscattered on the first tone 306) and payload is backscattered on the second tone 308). In a further example, the CW tones are switched within payload backscattering so that different segments of the payload are backscattered on different carrier wave tones, creating segment wise frequency hopping. In another example, if the AIoT device is configured to apply repetitions on the UL data, the tones of the CW may be switched so that each repetition is backscattered on a different tone to achieve both time and frequency diversity.

[0059] In an alternative example, the BS may configure multiple CW nodes to transmit a CW to the device at different time resources and each CW node transmits a different tone. Depending on the channel condition and distance between the CW nodesand the device, different carrier frequencies exhibit different fading. In other words, an optimal tone of CW transmitted from a certain node to the device might not be optimal for transmitting the CW from another node to the device. The BS may configure the frequency hopping and / or switching of CW tones by choosing the best CW node to transmit a certain tone.

[0060] In a second embodiment, the BS configures an AIoT device for frequency hopping of PDRCH. According to the second embodiment, the BS may send a configuration to an AIoT device to apply frequency hopping of PDRCH which may be applied for both passive and active AIoT devices. To enhance the performance of PDRCH and to avoid the frequency selectivity of the channel between the device and BS, the BS may send an indication to the AIoT device to apply different frequency shifts and / or frequency hopping on UL signal within an AIoT frequency response at different time resources so that the UL signal is backscattered and / or transmitted with hopping at different frequencies. The BS, based on known frequency shift capability of the device, may indicate to the device to apply a certain frequency shift at a certain time resource. Different devices, including passive and active devices, may have different capabilities in terms of how many frequencies shifts and how big of gaps between frequency shifts a device supports. For example, a first device type with power consumption of ~luW may support a small single frequency shift or may not support a frequency shift at all. A second device type with power consumption of a few 100s uW may support multiple frequency shifts with a large range. During initial access of the device, this capability may be indicated to the BS. The frequency hopping and / or frequency shifts at different time resources may be configured using DL channel (e.g., PRDCH), where the configuration indicates some frequency shifts and / or frequency hopping ranges (e.g., small or large and the corresponding time resources and / or lengths).

[0061] The BS may send a pattern of frequency shifts repeated until the device gets an indication from the BS to stop frequency hopping or to change the pattern. In one implementation, the control part of PRDCH carries a hopping pattern (e.g., [1, 2]) which indicates to the device to apply frequency shift 1 for a first time resource, frequency shift 2 for second time resource, and so forth (e.g., repeating the pattern). In one example, the time resources may be aligned with UL frame boundaries. In another example, frequency shifts are switched according to different portions of the UL frame(e.g., the preamble and the control are backscattered with frequency shift 1 and the payload is backscattered and / or transmitted with frequency shift 2). In a further example, the frequency shifts are changed within the payload backscattering and / or transmission so that for different segments of the payload different frequency shifts are applied. In another example, if the AIoT device is configured to apply repetitions on the UL data, different frequency shifts are applied on different repetitions.

[0062] In a third embodiment, there may be autonomous frequency hopping for PDRCH. According to the third embodiment, an AIoT device applies frequency hopping for PDRCH autonomously. The AIoT device is configured to enable autonomous frequency hopping depending on some pre-defined rules. For example, a device capable of frequency shift may apply frequency hopping for PDRCH if the quality and / or strength of the PRDCH is below a certain threshold or if there are multiple cyclic redundancy cycle (CRC) failures of PRDCH frames. The autonomous hopping may be disabled if the BS indicates to stop the autonomous frequency hopping, if frequency hopping and / or switching of carrier wave tones is already enabled for the corresponding PDRCH frames, or if the BS sends an explicit configuration for frequency hopping, in such configurations, the BS configuration of frequency hopping overrides the prepared autonomous frequency hopping of the device. AIoT device selects the proper frequency shifts to be applied on the UL frames and indicates to the BS the chosen frequency hopping and / or shifts and the corresponding time resources. In one implementation, the UL frame which contains a preamble, control part and payload is segmented into two or more portions (e.g., the preamble and control part of UL frame are transmitted and / or backscattered with no frequency shift so that the BS can synchronize to UL boundary and decode the information, while the payload is transmitted and / or backscattered with applying a frequency shift). The control part of each frame carries the applied frequency shift for the corresponding payload as shown in Figure 4.

[0063] Figure 4 illustrates an example 400 of signaling information of an applied frequency shift on an UL pay load in accordance with aspects of the present disclosure. The example 400 includes transmitted UL frames 402 and generated UL frames 404 to be transmitted based on the transmitted UL frames 402 over a time t and frequency f. A first frequency shift 406, a second frequency shift 408, and a third frequency shift 410are illustrated to show frequency shifts during different portions of the generated UL frames 404.

[0064] In one example, as shown in Figure 4, the payload of the UL frame is transmitted and / or backscattered with different frequency shifts, and the preamble and the control part are transmitted and / or backscattered with no frequency shift so that BS can synchronize with UL boundaries and decode the information. While the payload is segmented into multiple portions and different frequency shifts and / or frequency hopping with different ranges are applied on different segments of the payload as shown in Figure 5. The control part of the frame carries the applied frequency shifts. In one example, the control part of the PDRCH carriers the number of segments and frequency shift of each segment. In another example, the control part of PDRCH carries a hopping pattern applied on the segments (e.g., [1, 2]) indicates frequency shift 1 and frequency shift 2 are applied alternatively starting with shift 1 directly after the control part of PDRCH.

[0065] Figure 5 illustrates an example 500 of signaling information of an applied frequency shift on different segments of an UL payload in accordance with aspects of the present disclosure. The example 500 includes frequency shifts and / or a hopping pattern 502 and a payload 504 to be transmitted based on the frequency shifts and / or the hopping pattern 502 over a time t and frequency f. Seg#l, seg#2, seg#3, and seg#4 are illustrated as being transmitted on different frequencies. In one implementation, if the AIoT device is configured to apply repetitions on the UL data, different frequency shifts are applied on different repetitions.

[0066] Figure 6 illustrates an example of a UE 600 in accordance with aspects of the present disclosure. The UE 600 may include a processor 602, a memory 604, a controller 606, and a transceiver 608. The processor 602, the memory 604, the controller 606, or the transceiver 608, or various combinations thereof or various components thereof may be examples of means for performing various aspects of the present disclosure as described herein. These components may be coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more interfaces.

[0067] The processor 602, the memory 604, the controller 606, or the transceiver 608, or various combinations or components thereof may be implemented in hardware(e.g., circuitry). The hardware may include a processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), or other programmable logic device, or any combination thereof configured as or otherwise supporting a means for performing the functions described in the present disclosure.

[0068] The processor 602 may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, a CPU, an ASIC, a field programmable gate array (FPGA), or any combination thereof). In some implementations, the processor 602 may be configured to operate the memory 604. In some other implementations, the memory 604 may be integrated into the processor 602. The processor 602 may be configured to execute computer-readable instructions stored in the memory 604 to cause the UE 600 to perform various functions of the present disclosure.

[0069] The memory 604 may include volatile or non-volatile memory. The memory 604 may store computer-readable, computer-executable code including instructions when executed by the processor 602 cause the UE 600 to perform various functions described herein. The code may be stored in a non-transitory computer-readable medium such the memory 604 or another type of memory. Computer-readable media includes both non-transitory computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A non-transitory storage medium may be any available medium that may be accessed by a general-purpose or special-purpose computer.

[0070] In some implementations, the processor 602 and the memory 604 coupled with the processor 602 may be configured to cause the UE 600 to perform one or more of the functions described herein (e.g., executing, by the processor 602, instructions stored in the memory 604). For example, the processor 602 may support wireless communication at the UE 600 in accordance with examples as disclosed herein. For example, the processor 602 coupled with the memory 604 may be configured to cause the UE 600 (or an AIoT device) to transmit, to a base station, frequency hopping capabilities for an UL signal, wherein the frequency hopping capabilities include at least one frequency shift. The UE 600 (or an AIoT device) may also receive a frequency hopping configuration from the base station, wherein the frequency hopping configuration is based on the frequency hopping capabilities and includes information associated with applying a frequency shift to the UL signal. The UE 600 (or an AIoTdevice) may autonomously select a frequency hopping pattern based on the frequency hopping configuration. The UE 600 (or an AIoT device) may also transmit the UL signal to the base station using the frequency hopping pattern. The UE 600 (or an AIoT device) may transmit an indication to the base station indicating the autonomously selected frequency hopping pattern.

[0071] The controller 606 may manage input and output signals for the UE 600. The controller 606 may also manage peripherals not integrated into the UE 600. In some implementations, the controller 606 may utilize an operating system such as iOS®, ANDROID®, WINDOWS®, or other operating systems. In some implementations, the controller 606 may be implemented as part of the processor 602.

[0072] In some implementations, the UE 600 may include at least one transceiver 608. In some other implementations, the UE 600 may have more than one transceiver 608. The transceiver 608 may represent a wireless transceiver. The transceiver 608 may include one or more receiver chains 610, one or more transmitter chains 612, or a combination thereof.

[0073] A receiver chain 610 may be configured to receive signals (e.g., control information, data, packets) over a wireless medium. For example, the receiver chain 610 may include one or more antennas for receive the signal over the air or wireless medium. The receiver chain 610 may include at least one amplifier (e.g., a low-noise amplifier (LNA)) configured to amplify the received signal. The receiver chain 610 may include at least one demodulator configured to demodulate the receive signal and obtain the transmitted data by reversing the modulation technique applied during transmission of the signal. The receiver chain 610 may include at least one decoder for decoding the processing the demodulated signal to receive the transmitted data.

[0074] A transmitter chain 612 may be configured to generate and transmit signals (e.g., control information, data, packets). The transmitter chain 612 may include at least one modulator for modulating data onto a carrier signal, preparing the signal for transmission over a wireless medium. The at least one modulator may be configured to support one or more techniques such as amplitude modulation (AM), frequency modulation (FM), or digital modulation schemes like phase-shift keying (PSK) or quadrature amplitude modulation (QAM). The transmitter chain 612 may also include at least one power amplifier configured to amplify the modulated signal to an appropriatepower level suitable for transmission over the wireless medium. The transmitter chain 612 may also include one or more antennas for transmitting the amplified signal into the air or wireless medium.

[0075] Figure 7 illustrates an example of a processor 700 in accordance with aspects of the present disclosure. The processor 700 may be an example of a processor configured to perform various operations in accordance with examples as described herein. The processor 700 may include a controller 702 configured to perform various operations in accordance with examples as described herein. The processor 700 may optionally include at least one memory 704, which may be, for example, an L1 / L2 / L3 cache. Additionally, or alternatively, the processor 700 may optionally include one or more arithmetic -logic units (ALUs) 706. One or more of these components may be in electronic communication or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more interfaces (e.g., buses).

[0076] The processor 700 may be a processor chipset and include a protocol stack (e.g., a software stack) executed by the processor chipset to perform various operations (e.g., receiving, obtaining, retrieving, transmitting, outputting, forwarding, storing, determining, identifying, accessing, writing, reading) in accordance with examples as described herein. The processor chipset may include one or more cores, one or more caches (e.g., memory local to or included in the processor chipset (e.g., the processor 700) or other memory (e.g., random access memory (RAM), read-only memory (ROM), dynamic RAM (DRAM), synchronous dynamic RAM (SDRAM), static RAM (SRAM), ferroelectric RAM (FeRAM), magnetic RAM (MRAM), resistive RAM (RRAM), flash memory, phase change memory (PCM), and others).

[0077] The controller 702 may be configured to manage and coordinate various operations (e.g., signaling, receiving, obtaining, retrieving, transmitting, outputting, forwarding, storing, determining, identifying, accessing, writing, reading) of the processor 700 to cause the processor 700 to support various operations in accordance with examples as described herein. For example, the controller 702 may operate as a control unit of the processor 700, generating control signals that manage the operation of various components of the processor 700. These control signals include enabling or disabling functional units, selecting data paths, initiating memory access, and coordinating timing of operations.

[0078] The controller 702 may be configured to fetch (e.g., obtain, retrieve, receive) instructions from the memory 704 and determine subsequent instruction(s) to be executed to cause the processor 700 to support various operations in accordance with examples as described herein. The controller 702 may be configured to track memory address of instructions associated with the memory 704. The controller 702 may be configured to decode instructions to determine the operation to be performed and the operands involved. For example, the controller 702 may be configured to interpret the instruction and determine control signals to be output to other components of the processor 700 to cause the processor 700 to support various operations in accordance with examples as described herein. Additionally, or alternatively, the controller 702 may be configured to manage flow of data within the processor 700. The controller 702 may be configured to control transfer of data between registers, arithmetic logic units (ALUs), and other functional units of the processor 700.

[0079] The memory 704 may include one or more caches (e.g., memory local to or included in the processor 700 or other memory, such RAM, ROM, DRAM, SDRAM, SRAM, MRAM, flash memory, etc. In some implementations, the memory 704 may reside within or on a processor chipset (e.g., local to the processor 700). In some other implementations, the memory 704 may reside external to the processor chipset (e.g., remote to the processor 700).

[0080] The memory 704 may store computer-readable, computer-executable code including instructions that, when executed by the processor 700, cause the processor 700 to perform various functions described herein. The code may be stored in a non- transitory computer-readable medium such as system memory or another type of memory. The controller 702 and / or the processor 700 may be configured to execute computer-readable instructions stored in the memory 704 to cause the processor 700 to perform various functions. For example, the processor 700 and / or the controller 702 may be coupled with or to the memory 704, the processor 700, the controller 702, and the memory 704 may be configured to perform various functions described herein. In some examples, the processor 700 may include multiple processors and the memory 704 may include multiple memories. One or more of the multiple processors may be coupled with one or more of the multiple memories, which may, individually or collectively, be configured to perform various functions herein.

[0081] The one or more ALUs 706 may be configured to support various operations in accordance with examples as described herein. In some implementations, the one or more ALUs 706 may reside within or on a processor chipset (e.g., the processor 700). In some other implementations, the one or more ALUs 706 may reside external to the processor chipset (e.g., the processor 700). One or more ALUs 706 may perform one or more computations such as addition, subtraction, multiplication, and division on data. For example, one or more ALUs 706 may receive input operands and an operation code, which determines an operation to be executed. One or more ALUs 706 be configured with a variety of logical and arithmetic circuits, including adders, subtractors, shifters, and logic gates, to process and manipulate the data according to the operation. Additionally, or alternatively, the one or more ALUs 706 may support logical operations such as AND, OR, exclusive-OR (XOR), not-OR (NOR), and not-AND (NAND), enabling the one or more ALUs 706 to handle conditional operations, comparisons, and bitwise operations.

[0082] The processor 700 may support wireless communication in accordance with examples as disclosed herein. The processor 700 may be configured to or operable to support a means for: transmitting, to a base station, frequency hopping capabilities for an UL signal, wherein the frequency hopping capabilities include at least one frequency shift, receiving a frequency hopping configuration from the base station, wherein the frequency hopping configuration is based on the frequency hopping capabilities and includes information associated with applying a frequency shift to the UL signal, autonomously selecting a frequency hopping pattern based on the frequency hopping configuration, transmitting the UL signal to the base station using the frequency hopping pattern, and transmitting an indication to the base station indicating the autonomously selected frequency hopping pattern.

[0083] Figure 8 illustrates an example of a NE 800 in accordance with aspects of the present disclosure. The NE 800 may include a processor 802, a memory 804, a controller 806, and a transceiver 808. The processor 802, the memory 804, the controller 806, or the transceiver 808, or various combinations thereof or various components thereof may be examples of means for performing various aspects of the present disclosure as described herein. These components may be coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more interfaces.

[0084] The processor 802, the memory 804, the controller 806, or the transceiver 808, or various combinations or components thereof may be implemented in hardware (e.g., circuitry). The hardware may include a processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), or other programmable logic device, or any combination thereof configured as or otherwise supporting a means for performing the functions described in the present disclosure.

[0085] The processor 802 may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, a CPU, an ASIC, an FPGA, or any combination thereof). In some implementations, the processor 802 may be configured to operate the memory 804. In some other implementations, the memory 804 may be integrated into the processor 802. The processor 802 may be configured to execute computer-readable instructions stored in the memory 804 to cause the NE 800 to perform various functions of the present disclosure. For example, the processor 802 coupled with the memory 804 may be configured to cause the NE 800 to: determine a configuration comprising one or more of: a frequency hopping configuration associated with different tones for an external node, wherein a frequency hopping indicated by the frequency hopping configuration is associated with a frequency response of an AIoT device; and a frequency hopping operation associated with the AIoT device, wherein the frequency hopping operation comprises applying a frequency shift to an UL signal, and transmit the configuration.

[0086] The memory 804 may include volatile or non-volatile memory. The memory 804 may store computer-readable, computer-executable code including instructions when executed by the processor 802 cause the NE 800 to perform various functions described herein. The code may be stored in a non-transitory computer-readable medium such the memory 804 or another type of memory. Computer-readable media includes both non-transitory computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A non-transitory storage medium may be any available medium that may be accessed by a general-purpose or special-purpose computer.

[0087] In some implementations, the processor 802 and the memory 804 coupled with the processor 802 may be configured to cause the NE 800 to perform one or more of the functions described herein (e.g., executing, by the processor 802, instructionsstored in the memory 804). For example, the processor 802 may support wireless communication at the NE 800 in accordance with examples as disclosed herein.

[0088] The controller 806 may manage input and output signals for the NE 800. The controller 806 may also manage peripherals not integrated into the NE 800. In some implementations, the controller 806 may utilize an operating system such as iOS®, ANDROID®, WINDOWS®, or other operating systems. In some implementations, the controller 806 may be implemented as part of the processor 802.

[0089] In some implementations, the NE 800 may include at least one transceiver 808. In some other implementations, the NE 800 may have more than one transceiver 808. The transceiver 808 may represent a wireless transceiver. The transceiver 808 may include one or more receiver chains 810, one or more transmitter chains 812, or a combination thereof.

[0090] A receiver chain 810 may be configured to receive signals (e.g., control information, data, packets) over a wireless medium. For example, the receiver chain 810 may include one or more antennas for receive the signal over the air or wireless medium. The receiver chain 810 may include at least one amplifier (e.g., a low-noise amplifier (LNA)) configured to amplify the received signal. The receiver chain 810 may include at least one demodulator configured to demodulate the receive signal and obtain the transmitted data by reversing the modulation technique applied during transmission of the signal. The receiver chain 810 may include at least one decoder for decoding the processing the demodulated signal to receive the transmitted data.

[0091] A transmitter chain 812 may be configured to generate and transmit signals (e.g., control information, data, packets). The transmitter chain 812 may include at least one modulator for modulating data onto a carrier signal, preparing the signal for transmission over a wireless medium. The at least one modulator may be configured to support one or more techniques such as amplitude modulation (AM), frequency modulation (FM), or digital modulation schemes like phase-shift keying (PSK) or quadrature amplitude modulation (QAM). The transmitter chain 812 may also include at least one power amplifier configured to amplify the modulated signal to an appropriate power level suitable for transmission over the wireless medium. The transmitter chain 812 may also include one or more antennas for transmitting the amplified signal into the air or wireless medium.

[0092] Figure 9 illustrates a flowchart of a method 900 in accordance with aspects of the present disclosure. The operations of the method 900 may be implemented by a NE (e.g., base station) as described herein. In some implementations, a NE 800 may execute a set of instructions to control the function elements of a processor to perform the described functions.

[0093] At 902, the method may include determining a configuration comprising one or more of: a frequency hopping configuration associated with different tones for an external node, wherein a frequency hopping indicated by the frequency hopping configuration is associated with a frequency response of an AIoT device; and a frequency hopping operation associated with the AIoT device, wherein the frequency hopping operation comprises applying a frequency shift to an UL signal. The operations of 902 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 902 may be performed by a NE as described with reference to Figure 8.

[0094] At 904, the method may include transmitting the configuration. The operations of 904 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 904 may be performed by a NE as described with reference to Figure 8.

[0095] Figure 10 illustrates a flowchart of a method 1000 in accordance with aspects of the present disclosure. The operations of the method 1000 may be implemented by a device (e.g., AIoT device) as described herein. In some implementations, a UE 600 may execute a set of instructions to control the function elements of a processor to perform the described functions.

[0096] At 1002, the method may include transmitting, to a base station, frequency hopping capabilities for an UL signal, wherein the frequency hopping capabilities include at least one frequency shift. The operations of 1002 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 1002 may be performed by a UE as described with reference to Figure 6.

[0097] At 1004, the method may include receiving a frequency hopping configuration from the base station, wherein the frequency hopping configuration is based on the frequency hopping capabilities and includes information associated with applying a frequency shift to the UL signal. The operations of 1004 may be performedin accordance with examples as described herein. In some implementations, aspects of the operations of 1004 may be performed by a UE as described with reference to Figure 6.

[0098] At 1006, the method may include autonomously selecting a frequency hopping pattern based on the frequency hopping configuration. The operations of 1006 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 1006 may be performed by a UE as described with reference to Figure 6.

[0099] At 1008, the method may include transmitting the UL signal to the base station using the frequency hopping pattern. The operations of 1008 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 1008 may be performed by a UE as described with reference to Figure 6.

[0100] At 1010, the method may include transmitting an indication to the base station indicating the autonomously selected frequency hopping pattern. The operations of 1010 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 1010 may be performed by a UE as described with reference to Figure 6.

[0101] It should be noted that the methods described herein describe possible implementations, and that the operations and the steps may be rearranged or otherwise modified and that other implementations are possible.

[0102] The description herein is provided to enable a person having ordinary skill in the art to make or use the disclosure. Various modifications to the disclosure will be apparent to a person having ordinary skill in the art, and the generic principles defined herein may be applied to other variations without departing from the scope of the disclosure. Thus, the disclosure is not limited to the examples and designs described herein but is to be accorded the broadest scope consistent with the principles and novel features disclosed herein.

Claims

CLAIMSWhat is claimed is:1 . A base station, comprising: at least one memory; and at least one processor coupled with the at least one memory and configured to cause the base station to: determine a configuration comprising one or more of: a frequency hopping configuration associated with different tones for an external node, wherein a frequency hopping indicated by the frequency hopping configuration is associated with a frequency response of an ambient internet of things (AIoT) device; and a frequency hopping operation associated with the AIoT device, wherein the frequency hopping operation comprises applying a frequency shift to an uplink (UL) signal; and transmit the configuration.

2. The base station of claim 1, wherein the configuration indicates a list of tones for transmitting a carrier wave and corresponding time resources.

3. The base station of claim 1, wherein the configuration indicates a row index of a table that holds tone switching patterns and time resources for switching the tones.

4. The base station of claim 1, wherein time resources for hopping are aligned with an UL frame boundary and a different tone of a carrier wave is used for each UL frame.

5. The base station of claim 1, wherein time resources are associated with different segments of an UL frame and different carrier wave tones are used for different segments of the UL frame.

6. The base station of claim 1, wherein, in response to the device being configured to transmit repetitions of UL data, time resources different wave tone are associated with different repetitions.

7. The base station of claim 1, wherein the configuration indicates that the device is to apply different frequency shifts on a signal within a frequency response at different time resources.

8. The base station of claim 1, wherein time resources for shifting a frequency are aligned with an UL frame boundary.

9. The base station of claim 1, wherein time resources are associated with different segments of an UL frame and a different frequency shift is applied for each segment of the UL frame.

10. The base station of claim 1, wherein, in response to the device being configured to transmit repetitions of UL data, time resources for changing a frequency shift are associated with different repetitions.

11. The base station of claim 1, wherein the configuration is transmitted to the external node.

12. The base station of claim 1, wherein the configuration is transmitted to the AIoT device.

13. An ambient internet of things (AIoT) device, comprising: at least one memory; and at least one processor coupled with the at least one memory and configured to cause the AIoT device to: transmit, to a base station, frequency hopping capabilities for an uplink (UL) signal, wherein the frequency hopping capabilities include at least one frequency shift; receive a frequency hopping configuration from the base station, wherein the frequency hopping configuration is based on the frequency hopping capabilities and includes information associated with applying a frequency shift to the UL signal;autonomously select a frequency hopping pattern based on the frequency hopping configuration; transmit the UL signal to the base station using the frequency hopping pattern; and transmit an indication to the base station indicating the autonomously selected frequency hopping pattern.

14. The AIoT device of claim 13, wherein the frequency hopping configuration indicates that the device is to enable or disable autonomous switching between different frequency shifts during an UL transmission.

15. The AIoT device of claim 13, wherein the frequency hopping configuration indicates a pattern of applying frequency shifts and corresponding time resources for UL resources that carry information about selected frequency shifts.

16. A processor for an ambient internet of things (AIoT) device, comprising: at least one controller coupled with at least one memory and configured to cause the processor to: transmit, to a base station, frequency hopping capabilities for an uplink (UL) signal, wherein the frequency hopping capabilities include at least one frequency shift; receive a frequency hopping configuration from the base station, wherein the frequency hopping configuration is based on the frequency hopping capabilities and includes information associated with applying a frequency shift to the UL signal; autonomously select a frequency hopping pattern based on the frequency hopping configuration; transmit the UL signal to the base station using the frequency hopping pattern; and transmit an indication to the base station indicating the autonomously selected frequency hopping pattern.

17. The processor of claim 16, wherein the frequency hopping configuration indicates that the device is to enable or disable autonomous switching between different frequency shifts during an UL transmission.

18. The processor of claim 16, wherein the frequency hopping configuration indicates a pattern of applying frequency shifts and corresponding time resources for UL resources that carry information about selected frequency shifts.

19. A method performed by an ambient internet of things (AIoT) device, the method comprising: transmitting, to a base station, frequency hopping capabilities for an uplink (UL) signal, wherein the frequency hopping capabilities include at least one frequency shift; receiving a frequency hopping configuration from the base station, wherein the frequency hopping configuration is based on the frequency hopping capabilities and includes information associated with applying a frequency shift to the UL signal; autonomously selecting a frequency hopping pattern based on the frequency hopping configuration; transmitting the UL signal to the base station using the frequency hopping pattern; and transmitting an indication to the base station indicating the autonomously selected frequency hopping pattern.

20. The method of claim 19, wherein the frequency hopping configuration indicates that the device is to enable or disable autonomous switching between different frequency shifts during an UL transmission.

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