Spatial diversity for low power wake-up signals

Abstract

Methods, systems, and devices for wireless communication are described. A transmitter may modulate a set of bits into a sequence of modulated samples for transmission to a receiver. In some aspects, the transmitter may apply a phase-cyclic pattern to a sub-sequence of the modulated sample sequence to generate a phase-cyclic modulated sample sequence and a corresponding low-power signal. The transmitter may transmit the signals via respective antennas, and the receiver may receive the signals at different times. Alternatively, the transmitter may generate the signals according to a transmit interleaving pattern such that the signals are transmitted via different antennas at non-overlapping times or frequencies. The receiver may detect the signals using envelope detection.

Description

Technical Field

[0001] This disclosure relates to wireless communications, including spatial diversity for low-power wake-up signals. Background Art

[0002] Wireless communication systems are widely deployed to provide various types of communication content, such as voice, video, packet data, messaging, broadcasting, etc. These systems may be able to support communication with multiple users by sharing available system resources (e.g., time, frequency, and power). Examples of such multi-access systems include fourth-generation (4G) systems (such as Long-Term Evolution (LTE) systems, LTE-Advanced (LTE-A) systems, or LTE-A Pro systems) and fifth-generation (5G) systems (which may be referred to as New Radio (NR) systems). These systems may employ techniques such as Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Orthogonal FDMA (OFDMA), or Discrete Fourier Transform Spread Orthogonal Frequency Division Multiplexing (DFT-S-OFDM). A wireless multi-access communication system may include one or more base stations, each of which supports wireless communication of communication devices, which may be referred to as User Equipment (UE).

[0003] In some wireless communication systems, one or more receivers may use a modulation scheme such as On-Off Keying (OOK) to detect low-power wake-up signals. However, in order to receive such signals, the receiver may not be able to achieve the same coverage as other channels. Summary of the Invention

[0004] The described techniques relate to improved methods, systems, devices, and apparatuses for supporting spatial diversity for low-power wake-up signals. For example, the described techniques provide for transmitting a modulated low-power wake-up signal according to a phase cycling pattern or a transmission interleaving pattern. In some cases, the transmitter may modulate one or more bits into a sequence of modulation samples and apply a phase cycling pattern to a subsequence of the modulation sample sequence to generate a corresponding phase-cycled modulation sample sequence. The transmitter may transmit a signal via a corresponding antenna based on the phase-cycled modulation sample sequence, and the receiver may receive the signal via a single receiving antenna and decode the signal. Alternatively, after modulating the bits into a sequence of modulation samples, the transmitter may generate multiple signals from the modulation sample sequence and according to a transmission interleaving pattern, which may indicate that the transmission of the signals is interleaved across different frequency subbands. The transmitter may transmit the signals according to the transmission interleaving pattern via the corresponding antennas and at non-overlapping times or frequencies. In this way, the transmitter may create spatial diversity by transmitting signals according to the phase cycling pattern or the transmission interleaving pattern via separate antennas, which may enable the receiver to operate at low power and receive the signal via a single antenna (e.g., using envelope detection).

[0005] Describes a method for wireless communication at a transmitter. The method may include: modulating one or more bits into a sequence of modulation samples for wireless transmission to a receiver; applying a first phase cycling pattern to a set of multiple subsequences of the sequence of modulation samples to generate a first phase-cycled modulation sample sequence for transmission via a first transmit antenna; applying a second phase cycling pattern to the set of multiple subsequences of the sequence of modulation samples to generate a second phase-cycled modulation sample sequence for transmission via a second transmit antenna; transmitting a first signal via the first transmit antenna based on the first phase-cycled modulation sample sequence; and transmitting a second signal via the second transmit antenna based on the second phase-cycled modulation sample sequence.

[0006] Describes an apparatus for wireless communication at a transmitter. The apparatus may include a processor, a memory coupled to the processor, and instructions stored in the memory. The instructions may be executed by the processor to cause the apparatus to: modulate one or more bits into a sequence of modulation samples for wireless transmission to a receiver; apply a first phase cycling pattern to a set of multiple subsequences of the sequence of modulation samples to generate a first phase-cycled modulation sample sequence for transmission via a first transmit antenna; apply a second phase cycling pattern to the set of multiple subsequences of the sequence of modulation samples to generate a second phase-cycled modulation sample sequence for transmission via a second transmit antenna; transmit a first signal via the first transmit antenna based on the first phase-cycled modulation sample sequence; and transmit a second signal via the second transmit antenna based on the second phase-cycled modulation sample sequence.

[0007] Describes another apparatus for wireless communication at a transmitter. The apparatus may include: means for modulating one or more bits into a sequence of modulation samples for wireless transmission to a receiver; means for applying a first phase cycling pattern to a set of multiple subsequences of the sequence of modulation samples to generate a first phase-cycled modulation sample sequence for transmission via a first transmit antenna; means for applying a second phase cycling pattern to the set of multiple subsequences of the sequence of modulation samples to generate a second phase-cycled modulation sample sequence for transmission via a second transmit antenna; means for transmitting a first signal via the first transmit antenna based on the first phase-cycled modulation sample sequence; and means for transmitting a second signal via the second transmit antenna based on the second phase-cycled modulation sample sequence.

[0008] Describes a non-transitory computer-readable medium storing code for wireless communication at a transmitter. The code may include instructions executable by a processor to perform the following operations: modulating one or more bits into a sequence of modulation samples for wireless transmission to a receiver; applying a first phase cycling pattern to a set of multiple subsequences of the sequence of modulation samples to generate a first phase-cycled modulation sample sequence for transmission via a first transmit antenna; applying a second phase cycling pattern to the set of multiple subsequences of the sequence of modulation samples to generate a second phase-cycled modulation sample sequence for transmission via a second transmit antenna; transmitting a first signal via the first transmit antenna based on the first phase-cycled modulation sample sequence; and transmitting a second signal via the second transmit antenna based on the second phase-cycled modulation sample sequence.

[0009] Some examples of the methods, apparatuses, and non-transitory computer-readable media described herein may further include operations, features, components, or instructions for performing the following operations: multiplying a first subsequence of the set of multiple subsequences by a first phase of the first phase cycling pattern for the first transmit antenna and multiplying the first subsequence of the set of multiple subsequences by a second phase of the second phase cycling pattern for the second transmit antenna, wherein the first phase may be different from the second phase.

[0010] Some examples of the methods, apparatuses, and non-transitory computer-readable media described herein may further include operations, features, components, or instructions for performing the following operations: applying the first phase cycling pattern to a first bit of the sequence of modulation samples and applying the second phase cycling pattern to the first bit of the sequence of modulation samples.

[0011] Some examples of the methods, apparatuses, and non-transitory computer-readable media described herein may further include operations, features, components, or instructions for performing the following operations: converting the first phase-cycled modulation sample sequence into a first orthogonal frequency division multiplexing (OFDM) waveform and converting the second phase-cycled modulation sample sequence into a second OFDM waveform, wherein the first signal may be generated based on the first OFDM waveform and the second signal may be generated based on the second OFDM waveform.

[0012] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, the first OFDM waveform and the second OFDM waveform are mapped to resources corresponding to a single OFDM symbol.

[0013] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, the first OFDM waveform and the second OFDM waveform are mapped to resources corresponding to a set of multiple OFDM symbols.

[0014] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, the first signal and the second signal may be associated with zero mean.

[0015] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, the first phase cyclic modulation sample sequence and the second phase cyclic modulation sample sequence may each be associated with zero mean.

[0016] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, the first signal and the second signal include low-power synchronization signals, low-power preamble signals, low-power wake-up signals, or any combination thereof.

[0017] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, the modulation sample sequence includes an on-off keying (OOK) sample sequence, an amplitude shift keying (ASK) sample sequence, or a frequency shift keying (FSK) sample sequence.

[0018] A method for wireless communication at a transmitter is described. The method may include: modulating one or more bits into a modulation sample sequence for wireless transmission to a receiver; generating, according to a transmission interleaving pattern, a first signal for transmission via a first transmit antenna and a second signal for transmission via a second transmit antenna from the modulation sample sequence; and transmitting the first signal via the first transmit antenna and the second signal via the second transmit antenna, wherein the first signal and the second signal are transmitted via the first transmit antenna and the second transmit antenna, respectively, at non-overlapping times or via non-overlapping frequencies according to the transmission interleaving pattern.

[0019] An apparatus for wireless communication at a transmitter is described. The apparatus may include a processor, a memory coupled to the processor, and instructions stored in the memory. The instructions may be executed by the processor to cause the apparatus to: modulate one or more bits into a modulation sample sequence for wireless transmission to a receiver; generate, according to a transmission interleaving pattern, a first signal for transmission via a first transmit antenna and a second signal for transmission via a second transmit antenna from the modulation sample sequence; and transmit the first signal via the first transmit antenna and the second signal via the second transmit antenna, wherein the first signal and the second signal are transmitted via the first transmit antenna and the second transmit antenna, respectively, at non-overlapping times or via non-overlapping frequencies according to the transmission interleaving pattern.

[0020] Describes another apparatus for wireless communication at a transmitter. The apparatus may include: components for modulating one or more bits into a sequence of modulation samples for wireless transmission to a receiver; components for generating a first signal for transmission via a first transmit antenna and a second signal for transmission via a second transmit antenna from the sequence of modulation samples according to a transmit interleaving pattern; and components for transmitting the first signal via the first transmit antenna and the second signal via the second transmit antenna, wherein the first signal and the second signal are transmitted via the first transmit antenna and the second transmit antenna, respectively, at non-overlapping times or via non-overlapping frequencies according to the transmit interleaving pattern.

[0021] Describes a non-transitory computer-readable medium storing code for wireless communication at a transmitter. The code may include instructions executable by a processor to: modulate one or more bits into a sequence of modulation samples for wireless transmission to a receiver; generate a first signal for transmission via a first transmit antenna and a second signal for transmission via a second transmit antenna from the sequence of modulation samples according to a transmit interleaving pattern; and transmit the first signal via the first transmit antenna and the second signal via the second transmit antenna, wherein the first signal and the second signal are transmitted via the first transmit antenna and the second transmit antenna, respectively, at non-overlapping times or via non-overlapping frequencies according to the transmit interleaving pattern.

[0022] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, the transmit interleaving pattern indicates the transmission of the first signal and the second signal interleaved across different frequency subbands of a resource allocation.

[0023] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, transmitting the first signal and the second signal may include operations, features, components, or instructions for: transmitting the first signal during a first portion of an on-duration of the sequence of modulation samples and transmitting the second signal during a second portion of the on-duration of the sequence of modulation samples, wherein according to the transmit interleaving pattern, the first portion and the second portion of the on-duration occur at these non-overlapping times.

[0024] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, a first transmit power level associated with the first signal during the first portion of the on-duration may be equal to a second transmit power level associated with the second signal during the second portion of the on-duration.

[0025] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, transmitting the first signal and the second signal may include operations, features, components, or instructions for: transmitting the first signal, which may be a first interleaving, during a first portion of the on-duration of the modulated sample sequence and transmitting the second signal, which may be a second interleaving, during a second portion of the on-duration of the modulated sample sequence, wherein the first interleaving and the second interleaving may be non-overlapping in time according to a transmission interleaving pattern.

[0026] Some examples of the methods, apparatuses, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for: transmitting the first signal via the first transmit antenna in a first sub-band of the allocated bandwidth and transmitting the second signal via the second transmit antenna using a second sub-band of the allocated bandwidth, wherein the first sub-band may be different from the second sub-band.

[0027] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, generating the first signal and the second signal may include operations, features, components, or instructions for: generating the first signal and the second signal according to the transmission interleaving pattern indicating application of a phase ramp in the frequency domain.

[0028] Some examples of the methods, apparatuses, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for: converting a first interleaved modulated sample sequence into a first OFDM waveform and converting a second interleaved modulated sample sequence into a second OFDM waveform, wherein the first signal may be generated based on the first OFDM waveform and the second signal may be generated based on the second OFDM waveform.

[0029] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, the first OFDM waveform and the second OFDM waveform are mapped to resources corresponding to a single OFDM symbol.

[0030] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, the first OFDM waveform and the second OFDM waveform are mapped to resources corresponding to a set of multiple OFDM symbols.

[0031] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, the first signal and the second signal include low-power synchronization signals, low-power preamble signals, low-power wake-up signals, or any combination thereof.

[0032] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, the modulated sample sequence includes an OOK sample sequence, an ASK sample sequence, or an FSK sample sequence. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 Illustrates examples of wireless communication systems supporting spatial diversity for low-power wake-up signals in accordance with one or more aspects of the present disclosure.

[0034] Figure 2 Illustrates examples of phase cycling schemes supporting spatial diversity for low-power wake-up signals in accordance with one or more aspects of the present disclosure.

[0035] Figures 3 to 5 Illustrates examples of transmission interleaving schemes supporting spatial diversity for low-power wake-up signals in accordance with one or more aspects of the present disclosure.

[0036] Figure 6 and Figure 7 Illustrates examples of process flows supporting spatial diversity for low-power wake-up signals in accordance with one or more aspects of the present disclosure.

[0037] Figure 8 and Figure 9 Illustrates a block diagram of an apparatus supporting spatial diversity for low-power wake-up signals in accordance with one or more aspects of the present disclosure.

[0038] Figure 10 Illustrates a block diagram of a communication manager supporting spatial diversity for low-power wake-up signals in accordance with one or more aspects of the present disclosure.

[0039] Figure 11 Illustrates a diagram of a system including an apparatus supporting spatial diversity for low-power wake-up signals in accordance with one or more aspects of the present disclosure.

[0040] Figures 12 to 17 Illustrates a flowchart showing a method supporting spatial diversity for low-power wake-up signals in accordance with one or more aspects of the present disclosure. DETAILED DESCRIPTION

[0041] In some wireless communication systems, wireless devices may transmit and receive low-power wake-up signals. To reduce power consumption when receiving low-power wake-up signals, the transmitter may use waveforms that reduce complex baseband processing. For example, the transmitter may use amplitude-shift keying (ASK), frequency-shift keying (FSK), or on-off keying (OOK) to modulate the low-power wake-up signal, and the receiver may use a filter and envelope detection to demodulate the low-power wake-up signal. For these modulation schemes, the receiver (which may be a low-power receiver) may recover the amplitude of the signal, but may lose the phase of the signal. Additionally, the receiver may be equipped with a single receiving antenna instead of multiple antennas. These conditions may limit the receiver from achieving the same coverage as other new radio (NR) signals (e.g., physical downlink control channel (PDCCH)) received by a primary (e.g., master) radio having multiple receiving antennas and using complex baseband or coherent processing.

[0042] The techniques, systems, and devices described herein support spatial diversity for low-power wake-up signals based on ASK, FSK, or OOK. In some cases, to create such spatial diversity when the receiver (e.g., low-power receiver, user equipment (UE)) uses a single receiving antenna and the transmitter (e.g., network node) uses multiple transmitting antennas, the transmitter may use a phase cycling mode or a transmit interleaving mode to generate the signal. The transmitter may modulate one or more bits into a sequence of modulation samples and apply the phase cycling mode to a subsequence of the sequence of modulation samples to generate a corresponding phase-cycled modulation sample sequence. The transmitter may transmit the signal via the corresponding antennas based on the phase-cycled modulation sample sequence, and the receiver may receive and decode the signal via a single receiving antenna.

[0043] Alternatively, after modulating the bits into a sequence of modulation samples, the transmitter may generate multiple signals from the sequence of modulation samples and according to a transmit interleaving mode, which may indicate that the transmission of the signals is interleaved across different frequency subbands. The transmitter may transmit the signals according to the transmit interleaving mode via the corresponding antennas and at non-overlapping times or frequencies. In this way, the transmitter may create spatial diversity by transmitting the signals according to the phase cycling mode or the transmit interleaving mode via separate antennas, which may enable the receiver to operate at low power and receive the signal via a single antenna (e.g., using envelope detection).

[0044] Aspects of the present disclosure are first described in the context of a wireless communication system. Aspects of the present disclosure are subsequently described in the context of a phase cycling scheme, a transmit interleaving scheme, and a process flow. Aspects of the present disclosure are further illustrated and described by means of diagrams, system diagrams, and flowcharts related to spatial diversity for low-power wake-up signals.

[0045] Figure 1An example of a wireless communication system 100 that supports spatial diversity for low-power wake-up signals in accordance with one or more aspects of the present disclosure is illustrated. The wireless communication system 100 may include one or more network entities 105, one or more UEs 115, and a core network 130. In some examples, the wireless communication system 100 may be a Long Term Evolution (LTE) network, an LTE-Advanced (LTE-A) network, an LTE-A Pro network, a New Radio (NR) network, or a network operating in accordance with other systems and radio technologies, including future systems and radio technologies not explicitly mentioned herein.

[0046] The network entities 105 may be dispersed throughout a geographic area to form the wireless communication system 100 and may include devices in various forms or having different capabilities. In various examples, the network entities 105 (e.g., network nodes 105) may be referred to as network elements, mobility elements, radio access network (RAN) nodes, or network equipment, among other things. In some examples, the network entities 105 and the UEs 115 may communicate wirelessly via one or more communication links 125 (e.g., radio frequency (RF) access links). For example, the network entity 105 may support a coverage area 110 (e.g., a geographic coverage area) within which the UEs 115 and the network entity 105 may establish one or more communication links 125. The coverage area 110 may be an example of a geographic area within which the network entity 105 and the UEs 115 may support signal communication in accordance with one or more radio access technologies (RATs).

[0047] The UEs 115 may be dispersed throughout the coverage area 110 of the wireless communication system 100, and each UE 115 may be stationary or mobile, or stationary and mobile at different times. The UEs 115 may be devices in various forms or having different capabilities. Figure 1 Some example UEs 115 are illustrated. The UEs 115 described herein may be capable of supporting communication with various types of devices, such as Figure 1 other UEs 115 or network entities 105 as shown.

[0048] As described herein, a node of the wireless communication system 100 (which may be referred to as a network node or a wireless node) can be a network entity 105 (e.g., any network entity described herein), a UE 115 (e.g., any UE described herein), a network controller, a device, an apparatus, a computing system, one or more components, or another suitable processing entity configured to perform any of the techniques described herein. For example, the node can be a UE 115. As another example, the node can be a network entity 105. As yet another example, a first node can be configured to communicate with a second node or a third node. In one aspect of this example, the first node can be a UE 115, the second node can be a network entity 105, and the third node can be a UE 115. In another aspect of this example, the first node can be a UE 115, the second node can be a network entity 105, and the third node can be a network entity 105. In other aspects of this example, the first node, the second node, and the third node can be different from these examples. Similarly, references to UE 115, network entity 105, device, apparatus, computing system, etc. can include the disclosure of UE 115, network entity 105, device, apparatus, computing system, etc. as nodes. For example, the disclosure that a UE 115 is configured to receive information from a network entity 105 also discloses that a first node is configured to receive information from a second node.

[0049] In some examples, the network entity 105 can communicate with the core network 130, or with each other, or both. For example, the network entity 105 can communicate with the core network 130 via one or more backhaul communication links 120 (e.g., according to S1, N2, N3, or other interface protocols). In some examples, the network entity 105 can communicate with each other directly (e.g., directly between network entities 105) or indirectly (e.g., via the core network 130) via a backhaul communication link 120 (e.g., according to X2, Xn, or other interface protocols). In some examples, the network entity 105 can communicate with each other via a midhaul communication link 162 (e.g., according to a midhaul interface protocol) or a fronthaul communication link 168 (e.g., according to a fronthaul interface protocol) or any combination thereof. The backhaul communication link 120, the midhaul communication link 162, or the fronthaul communication link 168 can be or include one or more wired links (e.g., electrical links, fiber optic links), one or more wireless links (e.g., radio links, wireless optical links), etc. or various combinations thereof. The UE 115 can communicate with the core network 130 via a communication link 155.

[0050] One or more of the network entities 105 described herein may include or may be referred to as a base station 140 (e.g., transceiver base station, radio base station, NR base station, access point, radio transceiver, Node B, evolved Node B (eNB), next-generation Node B or giga Node B (either of which may be referred to as gNB), 5G NB, next-generation eNB (ng-eNB), home Node B, home evolved Node B, or other suitable terms). In some examples, the network entity 105 (e.g., base station 140) may be implemented in an integrated (e.g., monolithic, stand-alone) base station architecture that may be configured to utilize a protocol stack physically or logically integrated within a single network entity 105 (e.g., a single RAN node such as base station 140).

[0051] In some examples, the network entity 105 may be implemented in a disaggregated architecture (e.g., disaggregated base station architecture, disaggregated RAN architecture) that may be configured to utilize a protocol stack physically or logically distributed between two or more network entities 105 (such as an integrated access backhaul (IAB) network, open RAN (O-RAN) (e.g., a network configuration sponsored by the O-RAN Alliance) or virtualized RAN (vRAN) (e.g., cloud RAN (C-RAN)). For example, the network entity 105 may include one or more of the following: a central unit (CU) 160, a distributed unit (DU) 165, a radio unit (RU) 170, a RAN intelligent controller (RIC) 175 (e.g., near-real-time RIC (near-RT RIC), non-real-time RIC (non-RT RIC)), a service management and orchestration (SMO) 180 system, or any combination thereof. The RU 170 may also be referred to as a radio head, intelligent radio head, remote radio head (RRH), remote radio unit (RRU), or transmit receive point (TRP). One or more components of the network entity 105 in a disaggregated RAN architecture may be co-located, or one or more components of the network entity 105 may be located in distributed locations (e.g., separate physical locations). In some examples, one or more network entities 105 of the disaggregated RAN architecture may be implemented as virtual units (e.g., virtual CU (VCU), virtual DU (VDU), virtual RU (VRU)).

[0052] The functional split between the CU 160, DU 165, and RU 170 is flexible and can support different functions, depending on which functions are performed at the CU 160, DU 165, or RU 170 (e.g., network layer functions, protocol layer functions, baseband functions, RF functions, and any combination thereof). For example, a functional split of the protocol stack can be employed between the CU 160 and DU 165 such that the CU 160 can support one or more layers of the protocol stack and the DU 165 can support one or more different layers of the protocol stack. In some examples, the CU 160 can host higher protocol layer (e.g., layer 3 (L3), layer 2 (L2)) functions and signaling (e.g., radio resource control (RRC), service data adaptation protocol (SDAP), packet data convergence protocol (PDCP)). The CU 160 can be connected to one or more DU 165s or RU 170s, and one or more DU 165s or RU 170s can host lower protocol layers, such as layer 1 (L1) (e.g., physical (PHY) layer) or L2 (e.g., radio link control (RLC) layer, medium access control (MAC) layer) functions and signaling, and can each be at least partially controlled by the CU 160. Additionally or alternatively, a functional split of the protocol stack can be employed between the DU 165 and RU 170 such that the DU 165 can support one or more layers of the protocol stack and the RU 170 can support one or more different layers of the protocol stack. The DU 165 can support one or more different cells (e.g., via one or more RU 170s). In some cases, the functional split between the CU 160 and DU 165 or between the DU 165 and RU 170 can be within a protocol layer (e.g., some functions of a protocol layer can be performed by one of the CU 160, DU 165, or RU 170, while other functions of that protocol layer are performed by a different one of the CU 160, DU 165, or RU 170). The CU 160 can be further functionally split into a CU control plane (CU-CP) and a CU user plane (CU-UP) function. The CU 160 can be connected to one or more DU 165s via an intermediate transport communication link 162 (e.g., F1, F1-c, F1-u), and the DU 165 can be connected to one or more RU 170s via a fronthaul communication link 168 (e.g., open fronthaul (FH) interface). In some examples, the intermediate transport communication link 162 or the fronthaul communication link 168 can be implemented according to the interfaces (e.g., channels) between the layers of the protocol stack, which are supported by the respective network entities 105 communicating via these communication links.

[0053] In some wireless communication systems (e.g., wireless communication system 100), the infrastructure and spectrum resources for radio access may support wireless backhaul link capabilities to supplement wired backhaul connections, thereby providing an IAB network architecture (e.g., to core network 130). In some cases, in an IAB network, one or more network entities 105 (e.g., IAB node 104) may be controlled in part by each other. One or more IAB nodes 104 may be referred to as donor entities or IAB donors. One or more DUs 165 or one or more RUs 170 may be controlled in part by one or more CUs 160 associated with a donor network entity 105 (e.g., donor base station 140). One or more donor network entities 105 (e.g., IAB donors) may communicate with one or more additional network entities 105 (e.g., IAB nodes 104) via the supported access and backhaul links (e.g., backhaul communication link 120). The IAB node 104 may include an IAB mobile terminal (IAB-MT) controlled (e.g., scheduled) by the DU 165 of the coupled IAB donor. The IAB-MT may include a separate antenna set for relaying communication with the UE 115 or may share the same antenna (e.g., of the RU 170 of the IAB node 104) for access via the DU 165 of the IAB node 104 (e.g., referred to as a virtual IAB-MT (vIAB-MT)). In some examples, the IAB node 104 may include a DU 165 that supports communication links with additional entities (e.g., IAB nodes 104, UEs 115) within a relay chain or configuration (e.g., downstream) of the access network. In such cases, one or more components of the split RAN architecture (e.g., one or more IAB nodes 104 or components of the IAB node 104) may be configured to operate according to the techniques described herein.

[0054] In the context where the techniques described herein are applied to a split RAN architecture, one or more components of the split RAN architecture may be configured to support spatial diversity for low-power wake-up signals as described herein. For example, some operations described as being performed by the UE 115 or network entity 105 (e.g., base station 140) may additionally or alternatively be performed by one or more components of the split RAN architecture (e.g., IAB nodes 104, DUs 165, CUs 160, RUs 170, RICs 175, SMOs 180).

[0055] The UE 115 may include or may be referred to as a mobile device, wireless device, remote device, handheld device, or subscriber device, or some other suitable term, where "device" may also be referred to as a unit, station, terminal, or client, etc. The UE 115 may also include or may be referred to as a personal electronic device, such as a cellular phone, personal digital assistant (PDA), tablet computer, laptop computer, or personal computer. In some examples, the UE 115 may include or may be referred to as a wireless local loop (WLL) station, Internet of Things (IoT) device, Internet of Everything (IoE) device, or machine type communication (MTC) device, etc., which may be implemented in various objects such as appliances, vehicles, meters, etc.

[0056] The UE 115 described herein may be capable of communicating with various types of devices such as other UE 115s that may sometimes act as relays, as well as network entity 105 and network equipment including macro eNB or gNB, small cell eNB or gNB, or relay base stations, etc., as Figure 1 shown.

[0057] The UE 115 and the network entity 105 may wirelessly communicate with each other via one or more communication links 125 (e.g., access links) using resources associated with one or more carriers. The term "carrier" may refer to a set of RF spectrum resources having a defined physical layer structure for supporting the communication link 125. For example, a carrier for the communication link 125 may include a portion (e.g., bandwidth part (BWP)) of an RF spectrum band operating according to one or more physical layer channels for a given radio access technology (e.g., LTE, LTE-A, LTE-A Pro, NR). Each physical layer channel may carry acquisition signaling (e.g., synchronization signals, system information), control signaling for coordinating carrier operation, user data, or other signaling. The wireless communication system 100 may support communication with the UE 115 using carrier aggregation or multi-carrier operation. According to the carrier aggregation configuration, the UE 115 may be configured to have multiple downlink component carriers and one or more uplink component carriers. Carrier aggregation may be used for both frequency division duplex (FDD) and time division duplex (TDD) component carriers. Communication between the network entity 105 and other devices may refer to communication between these devices and any part (e.g., entity, sub-entity) of the network entity 105. For example, the terms "transmit", "receive", or "communicate" when referring to the network entity 105 may refer to any part of the network entity 105 of the RAN (e.g., base station 140, CU 160, DU 165, RU 170) communicating with another device (e.g., directly or via one or more other network entities 105).

[0058] A carrier can be associated with a specific bandwidth of the RF spectrum, and in some examples, the carrier bandwidth can be referred to as the "system bandwidth" of the carrier or the wireless communication system 100. For example, the carrier bandwidth can be one of a set of bandwidths of carriers of a specific radio access technology (e.g., 1.4 megahertz (MHz), 3 MHz, 5 MHz, 10 MHz, 15 MHz, 20 MHz, 40 MHz, or 80 MHz). Devices of the wireless communication system 100 (e.g., the network entity 105, the UE 115, or both) can have a hardware configuration that supports communication using a specific carrier bandwidth, or can be configured to support communication using one of a set of carrier bandwidths. In some examples, the wireless communication system 100 can include a network entity 105 or a UE 115 that supports concurrent communication using carriers associated with multiple carrier bandwidths. In some examples, each served UE 115 can be configured to operate using a portion (e.g., a sub-band, a BWP) or all of the carrier bandwidth.

[0059] The signal waveform transmitted via a carrier can include multiple sub-carriers (e.g., using multi-carrier modulation (MCM) techniques such as orthogonal frequency division multiplexing (OFDM) or discrete Fourier transform spread OFDM (DFT-S-OFDM)). In a system employing an MCM technique, a resource element can refer to the resource of one symbol period (e.g., the duration of one modulation symbol) and one sub-carrier, in which case the symbol period and the sub-carrier spacing can be inversely related. The number of bits carried by each resource element can depend on the modulation scheme (e.g., the order of the modulation scheme, the decoding rate of the modulation scheme, or both), such that a relatively large number of resource elements (e.g., in the transmission duration) and a relatively high-order modulation scheme can correspond to a relatively high communication rate. Wireless communication resources can refer to a combination of RF spectrum resources, time resources, and spatial resources (e.g., spatial layers or beams), and the use of multiple spatial resources can increase the data rate or data integrity for communication with the UE 115.

[0060] One or more parameter sets can be supported for a carrier, and the parameter set can include the sub-carrier spacing (Δf) and the cyclic prefix. A carrier can be divided into one or more BWPs with the same or different parameter sets. In some examples, the UE 115 can be configured with multiple BWPs. In some examples, a single BWP of a carrier can be active at a given time, and the communication of the UE 115 can be restricted to one or more active BWPs.

[0061] The time interval for the network entity 105 or the UE 115 can be expressed as a multiple of a basic time unit, which can refer to, for example, the sampling period T s = 1 / (Δf max · N f ) seconds, where Δfmax may represent the supported subcarrier spacing, and N f may represent the supported discrete Fourier transform (DFT) size. The time intervals of the communication resources may be organized according to radio frames each having a specified duration (e.g., 10 milliseconds (ms)). Each radio frame may be identified by a system frame number (SFN) (e.g., ranging from 0 to 1023).

[0062] Each frame may include a plurality of consecutively numbered subframes or time slots, and each subframe or time slot may have the same duration. In some examples, a frame may be divided (e.g., in the time domain) into subframes, and each subframe may be further divided into a certain number of time slots. Alternatively, each frame may include a variable number of time slots, and the number of time slots may depend on the subcarrier spacing. Each time slot may include a certain number of symbol periods (e.g., depending on the length of the cyclic prefix appended to each symbol period). In some wireless communication systems 100, a time slot may be further divided into a plurality of mini-slots associated with one or more symbols. Excluding the cyclic prefix, each symbol period may be associated with one or more (e.g., N f number of) sampling periods. The duration of a symbol period may depend on the subcarrier spacing or the operating frequency band.

[0063] A subframe, time slot, mini-slot, or symbol may be the smallest scheduling unit (e.g., in the time domain) of the wireless communication system 100 and may be referred to as a transmission time interval (TTI). In some examples, the TTI duration (e.g., the number of symbol periods in a TTI) may be variable. Additionally or alternatively, the smallest scheduling unit of the wireless communication system 100 may be dynamically selected (e.g., in a burst of shortened TTIs (sTTIs)).

[0064] Physical channels can be reused according to various techniques for communication using a carrier. For example, one or more of time-division multiplexing (TDM) techniques, frequency-division multiplexing (FDM) techniques, or hybrid TDM-FDM techniques can be used to multiplex physical control channels and physical data channels for signaling via a downlink carrier. The control region of a physical control channel (e.g., a control resource set (CORESET)) can be defined by a set of symbol periods and can span the system bandwidth of a carrier or an extension of a subgroup of the system bandwidth. One or more control regions (e.g., CORESETs) can be configured for a group of UEs 115. For example, one or more of the UEs 115 can monitor or search a control region for control information according to one or more search space sets, and each search space set can include one or more control channel candidates in one or more aggregation levels arranged in a cascaded manner. The aggregation level of a control channel candidate can refer to the amount of control channel resources (e.g., control channel elements (CCEs)) associated with the coded information for a control information format with a given payload size. The search space set can include: a common search space set configured to transmit control information to multiple UEs 115, and a UE-specific search space set for transmitting control information to a specific UE 115.

[0065] In some examples, the network entity 105 (e.g., the base station 140, the RU 170) can be movable and thus provide communication coverage for a moving coverage area 110. In some examples, different coverage areas 110 associated with different technologies can overlap, but the different coverage areas 110 can be supported by the same network entity 105. In some other examples, overlapping coverage areas 110 associated with different technologies can be supported by different network entities 105. The wireless communication system 100 can include, for example, a heterogeneous network in which different types of network entities 105 use the same or different radio access technologies to provide coverage for various coverage areas 110.

[0066] Some UEs 115 can be configured to adopt an operation mode that reduces power consumption, such as half-duplex communication (e.g., a mode that supports one-way communication via transmission or reception but does not transmit and receive concurrently). In some examples, half-duplex communication can be performed at a reduced peak rate. Other energy-saving techniques for UEs 115 include: entering a power-saving deep sleep mode when not participating in active communication, operating using limited bandwidth (e.g., according to narrowband communication), or a combination of these techniques. For example, some UEs 115 can be configured to operate using a narrowband protocol type associated with a defined portion or range (e.g., a set of subcarriers or resource blocks (RBs)) within a carrier, within the guard band of a carrier, or outside a carrier.

[0067] The wireless communication system 100 can be configured to support ultra-reliable communication or low-latency communication or various combinations thereof. For example, the wireless communication system 100 can be configured to support ultra-reliable low-latency communication (URLLC). The UE 115 can be designed to support ultra-reliable or low-latency or critical functions. Ultra-reliable communication can include private communication or group communication and can be supported by one or more services such as push-to-talk, video, or data. Support for ultra-reliable, low-latency functions can include prioritization of services, and such services can be used for public safety or general commercial applications. The terms ultra-reliable, low-latency, and ultra-reliable low-latency can be used interchangeably herein.

[0068] In some examples, the UE 115 can be configured to communicate directly with other UEs 115 via a device-to-device (D2D) communication link 135 (e.g., according to a peer-to-peer (P2P), D2D, or sidelink protocol). In some examples, one or more UEs 115 performing D2D communication in a group can be within the coverage area 110 of a network entity 105 (e.g., a base station 140, a RU 170), and the network entity can support aspects of such D2D communication configured (e.g., scheduled) by the network entity 105. In some examples, one or more UEs 115 in such a group can be outside the coverage area 110 of the network entity 105 or otherwise unable or not configured to receive transmissions from the network entity 105. In some examples, a group of UEs 115 communicating via D2D communication can support a one-to-many (1:M) system, where each UE 115 sends to each of the other UEs 115 in the group. In some examples, the network entity 105 can facilitate the scheduling of resources for D2D communication. In some other examples, D2D communication can be performed between UEs 115 without involving the network entity 105.

[0069] The core network 130 may provide user authentication, access authorization, tracking, Internet Protocol (IP) connectivity, and other access, routing, or mobility functions. The core network 130 may be an evolved packet core (EPC) or a 5G core (5GC), which may include at least one control plane entity for managing access and mobility (e.g., a mobility management entity (MME), an access and mobility management function (AMF)) and at least one user plane entity for routing packets or interconnecting to external networks (e.g., a serving gateway (S-GW), a packet data network (PDN) gateway (P-GW), or a user plane function (UPF)). The control plane entity may manage non-access stratum (NAS) functions such as mobility, authentication, and bearer management of the UE 115 served by a network entity 105 (e.g., a base station 140) associated with the core network 130. User IP packets may be passed through the user plane entity, which may provide IP address allocation and other functions. The user plane entity may be connected to the IP services 150 of one or more network operators. The IP services 150 may include access to the Internet, an intranet, an IP multimedia subsystem (IMS), or packet-switched streaming services.

[0070] The wireless communication system 100 may operate using one or more frequency bands that may be in the range of 300 megahertz (MHz) to 300 gigahertz (GHz). Generally, the region from 300 MHz to 3 GHz is known as the ultra-high frequency (UHF) region or the decimeter band because, in terms of length, the wavelength range is from approximately one decimeter to one meter. UHF waves may be blocked or redirected by buildings and environmental features (which may be referred to as clutter), but these waves may be sufficient to penetrate structures so that a macro cell can serve a UE 115 located indoors. Compared to communication using smaller frequencies and longer wavelengths in the high frequency (HF) or very high frequency (VHF) portions of the spectrum below 300 MHz, communication using UHF waves may be associated with smaller antennas and shorter ranges (e.g., less than 100 kilometers).

[0071] The wireless communication system 100 may utilize licensed and unlicensed RF spectrum bands. For example, the wireless communication system 100 may use an unlicensed band (such as the 5 GHz industrial, scientific, and medical (ISM) band) to employ licensed-assisted access (LAA), LTE unlicensed (LTE-U) radio access technology, or NR technology. When operating using an unlicensed RF spectrum band, devices such as the network entity 105 and the UE 115 may employ carrier sensing for collision detection and avoidance. In some examples, operations using an unlicensed band may be combined with component carriers operating using a licensed band based on a carrier aggregation configuration (e.g., LAA). Operations using unlicensed spectrum may include downlink transmissions, uplink transmissions, peer-to-peer (P2P) transmissions, or device-to-device (D2D) transmissions, among others.

[0072] The network entity 105 (e.g., base station 140, RU 170) or the UE 115 may be equipped with multiple antennas, which may be used to employ techniques such as transmit diversity, receive diversity, multiple-input multiple-output (MIMO) communication, or beamforming. The antennas of the network entity 105 or the UE 115 may be located within one or more antenna arrays or antenna panels, which may support MIMO operation or transmit or receive beamforming. For example, one or more base station antennas or antenna arrays may be co-located at an antenna assembly, such as at an antenna tower. In some examples, the antennas or antenna arrays associated with the network entity 105 may be located at different geographical locations. The network entity 105 may include an antenna array having a set of antenna ports arranged in multiple rows and columns that the network entity 105 may use for beamforming to support communication with the UE 115. Similarly, the UE 115 may include one or more antenna arrays that may support various MIMO or beamforming operations. Additionally or alternatively, the antenna panel may support RF beamforming for signals transmitted via the antenna ports.

[0073] Beamforming (which may also be referred to as spatial filtering, directional transmission, or directional reception) is a signal processing technique that may be used at a transmitting device or a receiving device (e.g., network entity 105, UE 115) to shape or direct an antenna beam (e.g., transmit beam, receive beam) along a spatial path between the transmitting device and the receiving device. Beamforming may be achieved by combining signals conveyed via the antenna elements of an antenna array such that some signals propagating in a particular direction relative to the antenna array experience constructive interference while other signals experience destructive interference. The adjustment of the signals conveyed via the antenna elements may include the transmitting device or the receiving device applying an amplitude offset, a phase offset, or both to the signals carried via the antenna elements associated with the device. The adjustment associated with each of these antenna elements may be defined by a set of beamforming weights associated with a particular direction (e.g., relative to the antenna array of the transmitting device or the receiving device or relative to some other direction).

[0074] The network entity 105 or the UE 115 may use beam scanning techniques as part of beamforming operations. For example, the network entity 105 (e.g., the base station 140, the RU 170) may use multiple antennas or antenna arrays (e.g., antenna panels) to perform beamforming operations for directional communication with the UE 115. Some signals (e.g., synchronization signals, reference signals, beam selection signals, or other control signals) may be sent by the network entity 105 multiple times along different directions. For example, the network entity 105 may send signals according to different sets of beamforming weights associated with different transmission directions. Transmissions along different beam directions may be used to identify (e.g., by the transmitting device, such as the network entity 105, or by the receiving device, such as the UE 115) the beam direction for later transmission or reception by the network entity 105.

[0075] Some signals (such as data signals associated with a specific receiving device) may be sent by the transmitting device (e.g., the transmitting network entity 105, the transmitting UE 115) along a single beam direction (e.g., the direction associated with the receiving device (such as the receiving network entity 105 or the receiving UE 115)). In some examples, the beam direction associated with the transmission along a single beam direction may be determined based on signals transmitted along one or more beam directions. For example, the UE 115 may receive one or more of the signals sent by the network entity 105 along different directions and may report to the network entity 105 an indication of the signal that the UE 115 receives with the highest signal quality or other acceptable signal quality.

[0076] In some examples, transmissions performed by a device (e.g., by network entity 105 or UE 115) may be carried out using multiple beam directions, and the device may use a combination of digital precoding or beamforming to generate a combined beam for transmission (e.g., from network entity 105 to UE 115). UE 115 may report feedback indicating precoding weights for one or more beam directions, and the feedback may correspond to a set of configured beams across the system bandwidth or one or more sub-bands. Network entity 105 may transmit reference signals (e.g., cell-specific reference signal (CRS), channel state information reference signal (CSI-RS)), which may or may not be precoded. UE 115 may provide feedback for beam selection, which may be a precoding matrix indicator (PMI) or codebook-based feedback (e.g., multi-panel codebook, linear combination codebook, port selection codebook). Although these techniques are described with reference to signals transmitted by network entity 105 (e.g., base station 140, RU 170) along one or more directions, UE 115 may use similar techniques for transmitting signals multiple times along different directions (e.g., for identifying beam directions used by UE 115 for subsequent transmissions or receptions), or for transmitting signals along a single direction (e.g., for transmitting data to a receiving device).

[0077] A receiving device (e.g., UE 115) may perform receiving operations according to multiple receiving configurations (e.g., directional listening) when receiving various signals (such as synchronization signals, reference signals, beam selection signals, or other control signals) from a receiving device (e.g., network entity 105). For example, the receiving device may perform receiving according to multiple receiving directions by: receiving via different antenna sub-arrays, processing the received signals according to different antenna sub-arrays, receiving according to different sets of receiving beamforming weights (e.g., different directional listening weight sets) applied to signals received at multiple antenna elements of an antenna array, or processing the received signals according to different sets of receiving beamforming weights applied to signals received at multiple antenna elements of an antenna array, where any of these may refer to "listening" according to different receiving configurations or receiving directions. In some examples, the receiving device may use a single receiving configuration to receive along a single beam direction (e.g., when receiving a data signal). The single receiving configuration may be aligned along a beam direction determined based on listening according to different receiving configuration directions (e.g., a beam direction determined to have the highest signal strength, highest signal-to-noise ratio (SNR), or other acceptable signal quality based on listening according to multiple beam directions).

[0078] In some cases, the wireless communication system 100 may support wireless devices with zero power or near-zero power (e.g., receivers, transmitters) and other lower power devices. To reduce the power consumption of the receiver, the wireless communication system 100 may support ASK-based signals, FSK-based signals, OOK-based signals, or any combination thereof. The receiver may use a filter or envelope detection when receiving such signals, which can reduce its power consumption compared to other forms of signal detection (e.g., coherent detection). For example, the network node 105 (e.g., transmitter) may send a low-power wake-up signal to the UE 115 (e.g., receiver), and the UE 115 may receive the signal using only the low-power wake-up radio instead of the main radio (when the main radio is in the sleep mode). Based on the received low-power wake-up signal, the UE 115 may wake up the main radio and use it to receive other higher-power signals.

[0079] The transmitter may design signal waveforms that can be received by a receiver using a low-power wake-up radio. Such waveforms may include ASK-based waveforms, FSK-based waveforms, and OOK-based waveforms, and the receiver may use a simple filter and envelope detector to demodulate these waveforms. Thus, the receiver can use reduced power to demodulate the low-power wake-up signal. However, because this receiver design is limited, the receiver may lack the same sensitivity or coverage when using a low-power wake-up radio (which may include a single antenna) as when using the main radio (which may include multiple antennas). That is, the more complex the receiver, the higher its sensitivity can be, where the sensitivity may refer to the minimum received power amount required for the receiver to function. For example, the low-power wake-up radio may operate at -80 dBm power, and the main radio may operate at -100 dBm power.

[0080] In some examples, the transmitter may generate cyclic prefix-OFDM compatible OOK signals (or other modulated signals). These signals can be placed in the OFDM time and frequency grid and have a limited bandwidth for a set of subcarriers allocated to OFDM (without generating interference to other non-OOK signals). In this way, the transmitter can generate an oversampled OOK signal and post-process the signal so that the signal can be placed in the OFDM time and frequency grid. By oversampling the OOK signal, the data rate of the OOK signal can be less than the actual sampling rate and bandwidth of the transmitted signal. That is, the transmitter can send a low-power wake-up signal far below the Nyquist rate. For example, the low-power wake-up signal can operate at a 4 MHz bandwidth at a data rate of approximately 100,000 bits per second.

[0081] In some examples, when receiving a low-power wake-up signal, a receiver (e.g., UE 115) may use low power and a single receive antenna (with simple hardware). To ensure that the coverage of such a low-power receiver matches that of a conventional, higher-power receiver, a transmitter (e.g., network node 105) may use its multiple transmit antennas to create spatial diversity. Instead of using spatial diversity techniques such as space-time coding, Alamouti code, space-time block coding (STBC), or space-frequency block coding (SFBC) and other spatial diversity techniques that may not be applicable to low-power wake-up radios that may not be able to obtain phase information, the transmitter may use in-symbol beam scanning and pre-coder cycling or interleaved transmission.

[0082] Wireless communication system 100 supports a phase cycling pattern and a transmission interleaving pattern for generating low-power signals. To create spatial diversity when a receiver (e.g., a low-power receiver, UE 115) uses a single receive antenna and a transmitter (e.g., network node 105) uses multiple transmit antennas, the transmitter may use the phase cycling pattern or the transmission interleaving pattern to generate signals. In some aspects, the transmitter may modulate one or more bits into a sequence of modulation samples and apply the phase cycling pattern to a subsequence of the sequence of modulation samples to generate a corresponding phase-cycled modulation sample sequence. The transmitter may transmit signals via corresponding antennas based on the phase-cycled modulation sample sequence, and the receiver may receive and decode the signals via a single receive antenna. Alternatively, after modulating the bits into a sequence of modulation samples, the transmitter may generate multiple signals from the sequence of modulation samples and according to the transmission interleaving pattern, which may indicate that the transmission of the signals is interleaved across different frequency subbands. The transmitter may transmit the signals according to the transmission interleaving pattern via corresponding antennas and at non-overlapping times or frequencies. In this way, the transmitter may create spatial diversity by transmitting signals via separate antennas according to the phase cycling pattern or the transmission interleaving pattern, which may enable the receiver to operate at low power and receive signals via a single antenna (e.g., using envelope detection).

[0083] Figure 2An example of a phase cycling scheme 200 that supports spatial diversity for low-power wake-up signals in accordance with one or more aspects of the present disclosure is illustrated. In some examples, the phase cycling scheme 200 may implement aspects of a wireless communication system 100 or may be implemented by aspects of the wireless communication system 100. For example, a transmitter (e.g., a wireless communication device such as a network node) may use the phase cycling scheme 200 to generate a signal 225 for transmission to a receiver (e.g., a wireless communication device such as a UE). In some examples, the transmitter may use the phase cycling scheme 200 for a case where the transmitter uses multiple antennas 230 to transmit a low-power signal (e.g., a low-power wake-up signal) to the receiver and the receiver uses a single antenna to receive the signal.

[0084] A wireless communication system may support communication between a transmitter and a receiver, which may include communication of low-power wake-up signals and other low-power signals. In some examples, the transmitter may support two or more antennas, including antenna 230-a (e.g., Tx antenna 1) and antenna 230-b (e.g., Tx antenna T, where T may represent the total number of transmit antennas). Since the receiver may be equipped with a single receive antenna, the transmitter may use a phase cycling pattern associated with the phase cycling scheme 200 to design a particular signal for transmission to the receiver such that the receiver may exploit different channels associated with the multiple antennas 230.

[0085] In some aspects, the transmitter may receive an information payload 205 that includes one or more bits (e.g., 1s and 0s). The transmitter may modulate the one or more bits into a sequence of modulated samples for wireless transmission to the receiver via the antennas 230. The sequence of modulated samples may be a sequence of OOK-modulated samples, a sequence of ASK-modulated samples, a sequence of FSK-modulated samples, or any other sequence of samples based on low-complexity modulation.

[0086] The transmitter may use in-symbol beam scanning or a precoder cycle to generate a signal for transmission with spatial diversity via the antennas 230. Within each oversampled time-domain modulation (e.g., OOK) symbol of the sequence of modulated samples during the on-duration, the transmitter may multiply the time-domain signal (represented as "x" in the sequence of modulated samples) by a corresponding phase sequence for the same OOK symbol on each of the antennas 230. For example, the sequence of modulated samples may have a length of M / K, which is further divided into L subsequences 210 (also referred to herein as sample groups) such that each subsequence 210 may include M / K / L samples, and each sample (e.g., including an "x" value) is multiplied by a phase. M may represent an integer multiple of K such that each on-off duration of the sequence of modulated samples is of the same length.

[0087] The transmitter may apply a first phase cycling pattern including a set of phases to subsequence 210 of the modulated sample sequence to generate a first phase cycled modulated sample sequence for transmission via antenna 230-a (e.g., the first antenna). Additionally, the transmitter may apply a second phase cycling pattern including a set of phases to subsequence 210 of the modulated sample sequence to generate a second phase cycled modulated sample sequence for transmission via antenna 230-b (e.g., the second antenna). For example, the first phase cycling pattern may include phases These phases are respectively applied to subsequence 210 corresponding to antenna 230-a (e.g., multiplying the respective subsequence by the respective phase), and the second phase cycling pattern may include phases These phases are respectively applied to subsequence 210 corresponding to antenna 230-b. The transmitter may apply the corresponding phase cycled modulated sample sequences for any number of antennas 230 (e.g., two or more antennas) used by the transmitter.

[0088] In some cases, the transmitter may multiply subsequence 210-a (e.g., the first subsequence of value "x") by the first phase of the first phase cycling pattern of antenna 230-a and multiply subsequence 210-d (e.g., the same first subsequence of value "x") by the second phase of the second phase cycling pattern of antenna 230-b, where the first phase and the second phase are different. This may be repeated for each subsequence 210 of the modulated sample sequences generated for each antenna 230. In this way, the transmitter may multiply the transmitted time-domain signal (e.g., the modulated sample sequence) by the corresponding phase sequences on each antenna 230 corresponding to the same modulated (e.g., OOK) symbol.

[0089] The transmitter may use different phases for each subsequence 210 (e.g., group of samples) or in some cases for each sample of the modulated symbols on each antenna 230. For example, the transmitter may multiply the phase by M / K / L samples of subsequence 210-a and multiply the phase by M / K / L samples of subsequence 210-b, and these subsequences are transmitted to the receiver via antenna 230-a, where subsequence 210-a and subsequence 210-b may include on symbols (e.g., the on duration of the first phase cycled modulated sample sequence). Subsequence 210-c may be the off duration of the first phase cycled modulated sample sequence and thus may include M / K zero samples. Additionally, the transmitter may multiply the phase by M / K / L samples of subsequence 210-d and multiply the phase Multiply by M / K / L samples of subsequence 210-e, which are used to be transmitted to the receiver via antenna 230-b, where subsequence 210-d and subsequence 210-e may include an on symbol (e.g., the on duration of the second phase cyclic modulation sample sequence). Subsequence 210-f may be the off duration of the second phase cyclic modulation sample sequence and thus may include M / K zeros.

[0090] The transmitter may apply a phase sequence to one modulation bit within the on duration of the modulation symbol of subsequence 210. For example, subsequence 210-a and subsequence 210-b within the on duration of the first phase cyclic modulation sample sequence for antenna 230-a may be included in the same bit, and likewise, subsequence 210-d and subsequence 210-e may be included in the same one bit within the on duration of the second phase cyclic modulation sample sequence. That is, the transmitter may apply the first phase cyclic pattern to the first bit of the modulation sample sequence for antenna 230-a and the second phase cyclic pattern to the first bit of the modulation sample sequence for antenna 230-b, respectively.

[0091] Additionally, within the same on duration of the modulation symbol, the transmitter may apply different pre-codings (e.g., different phases) to the modulation sample sequences transmitted via antenna 230. For example, the phase (applied to subsequence 210-a for antenna 230-a) and the phase (applied to subsequence 210-d for antenna 230-b) may correspond to the same pre-coder such that the pre-coder is applied to multiple antennas 230. When performing the pre-coding cycle, the transmitter may cycle across different subsequences 210 across different pre-coders. In this way, the second pre-coder may include the phase (applied to subsequence 210-b for antenna 230-a) and the phase (applied to subsequence 210-e for antenna 230-b). Additionally, each pre-coder may correspond to a generated beam such that the transmitter may transmit each of the L subsequences 210 in beams in slightly different directions.

[0092] The transmitter may transmit signal 225-a via antenna 230-a based on the first phase cyclic modulation sample sequence and transmit signal 225-b via antenna 230-b based on the second phase cyclic modulation sample sequence. In some examples, to generate signal 225, the transmitter may use the corresponding transform 215 and the corresponding waveform generator 220 to convert each phase cyclic modulation sample sequence into an OFDM waveform. In one example, waveform generator 220 may perform an N-point inverse fast Fourier transform (iFFT) algorithm on the output of transform 215 to generate the OFDM waveform, or may be another type of OFDM waveform generator. In one example, the transmitter may use waveform generator 220-a to convert the first phase cyclic modulation sample sequence into a first OFDM waveform and use waveform generator 220-b to convert the second phase cyclic modulation sample sequence into a second OFDM waveform, where signal 225-a is generated based on the first OFDM waveform and signal 225-b is generated based on the second OFDM waveform.

[0093] When converting the phase cyclic modulation sample sequence into an OFDM waveform, the transmitter may apply the corresponding transform 215 (e.g., transform 215-a for antenna 230-a and transform 215-b for antenna 230-b) to the phase cyclic modulation sample sequence. In doing so, the transmitter may convert the time-domain signal into the frequency domain such that the first OFDM waveform and the second OFDM waveform are mapped to resources corresponding to one or more OFDM symbols. In some cases, transform 215 may change the time-domain samples to the frequency domain such that they are mapped to a set of resource elements or resource blocks associated with the transmission of signal 225 (e.g., OOK transmission). In some cases, transform 215 may be an M-point DFT such that the OFDM waveform may be a modulation signal based on DFT-S-OFDM.

[0094] Additionally, signal 225 may be a low-power synchronization signal, a low-power preamble signal, a low-power wake-up signal, or any other low-power signal. The transmitter may transmit the low-power synchronization signal, the low-power preamble signal, the low-power wake-up signal, or any combination thereof via separate channels, or the transmitter may transmit the low-power synchronization signal and the low-power preamble signal before each low-power wake-up signal transmission. The receiver may use the low-power synchronization signal, the low-power preamble signal, or both to perform time or frequency synchronization with the transmitter and train the AGC of the receiver. Thus, the low-power synchronization signal, the low-power preamble signal, or both may have the same dynamic range as the low-power wake-up signal, e.g., the same precoder cycle or the same transmission interleaving pattern.

[0095] In one example, the transmitter may modulate a sequence of modulation samples for transmission to a receiver via antennas 230-a and 230-b (e.g., the number of transmit antennas may be T = 2), where the number of phase values is equal to L = 4 (e.g., subsequence 210-a, subsequence 210-b, subsequence 210-d, and subsequence 210-e). The transmitter may apply a phase pattern represented as a matrix to the subsequence 210, where j may represent a ninety-degree phase shift. Each row of the matrix may represent an antenna 230, and each column of the matrix may represent a pre-coder to be applied to each subsequence 210. Thus, the transmitter may avoid applying a phase shift to the samples transmitted via antenna 230-a and may apply a ninety-degree phase shift every quarter of the samples transmitted on antenna 230-b.

[0096] In another example, the transmitter may use a subset of the DFT matrix as a phase cycling pattern applied to the antennas 230. In such cases, the transmitter may apply a first DFT matrix to a first phase-cycled modulation sample sequence to generate a first DFT sequence and apply a second DFT matrix to a second phase-cycled modulation sample sequence to generate a second DFT sequence. The transmitter may then generate signals 225-a and 225-b based on the first DFT sequence and the second DFT sequence, respectively. The DFT matrix may be represented as where Q, q1,..., q L-1 may represent integers. Each row of the DFT matrix may represent an antenna 230 and each column of the DFT matrix may represent a beam pattern, such that the transmitter may apply beam scanning or pre-coder cycling within each modulation symbol.

[0097] In some cases, the transmitter may generate signals 225 on the respective antennas 230 such that the overall signal has a zero mean in the time domain, e.g., to avoid transmitting the signal as a direct current (DC) tone. Thus, the transmitter may select a sequence (e.g., x, x, x, x) for the on-duration that fills the modulation sample sequence such that after multiplying this sequence by the phase cycling pattern, the overall signal has a zero mean (e.g., the sum of the OOK samples in the on-duration equals zero). In this way, signals 225-a and 225-b may be associated with a zero mean, and the first phase-cycled modulation sample sequence and the second phase-cycled modulation sample sequence may each be associated with a zero mean. Having the transmitted signal have a zero mean may avoid any transmission on the DC tone and thus reduce DC leakage. Alternatively, the transmitter may explicitly remove the signal on the DC tone before transmitting the signal in the air. That is, the transmitter may calculate the average of the sequence (e.g., the phase cycling sequence) and subtract this average from the signal to make the signal have a zero mean and thus have zero power at the DC tone.

[0098] As described herein, spatial diversity may refer to using multiple wireless communication links to connect a transmitter and a receiver such that the transmitter and receiver can communicate over multiple channels. As long as at least one of these channels is available (e.g., lacks high traffic and interference), the transmitter and receiver can communicate successfully. If the receiver has four receive antennas, the receiver can receive four copies of a message from the transmitter to achieve spatial diversity. However, if the receiver (e.g., a low-power receiver using a low-power wake-up radio) has a single receive antenna, the receiver can receive messages transmitted simultaneously on the same resources, thus limiting the receiver's decoding ability due to the lack of spatial diversity in transmission. Therefore, when the receiver uses a single receive antenna, the transmitter can use the techniques described herein to create spatial diversity using its multiple transmit antennas.

[0099] Figure 3 Illustrated is an example of a transmission interleaving scheme 300 that supports spatial diversity for low-power wake-up signals in accordance with one or more aspects of the present disclosure. In some examples, the transmission interleaving scheme 300 may implement aspects of the wireless communication system 100 or may be implemented by aspects of the wireless communication system 100. For example, a transmitter (e.g., a wireless communication device such as a network node) may use the transmission interleaving scheme 300 to generate a signal 325 for transmission to a receiver (e.g., a wireless communication device such as a UE). In some examples, the transmitter may use the transmission interleaving scheme 300 for the case where the transmitter uses multiple antennas 330 to transmit a low-power signal (e.g., a low-power wake-up signal) to the receiver and the receiver uses a single antenna to receive the signal.

[0100] A wireless communication system may support communication between a transmitter and a receiver, which may include communication of low-power wake-up signals and other low-power signals. In some examples, the transmitter may support two or more antennas, including antenna 330-a (e.g., Tx antenna 1) and antenna 330-b (e.g., Tx antenna T, where T may represent the total number of transmit antennas). Since the receiver may be equipped with a single receive antenna, the transmitter can use transmission interleaving to design a particular signal for transmission to the receiver such that the receiver can utilize different channels associated with the multiple antennas 330.

[0101] In some aspects, the transmitter may receive an information payload 305 that includes one or more bits (e.g., 1 and 0). The transmitter may modulate the one or more bits into a sequence of modulation samples for wireless transmission via an antenna 330 to a receiver. The sequence of modulation samples may be a sequence of OOK-modulated samples, a sequence of ASK-modulated samples, a sequence of FSK-modulated samples, or any other sequence of samples based on low-complexity modulation. Additionally, the sequence of modulation samples, which may also be referred to as a time-domain signal, may have a length of M / K samples, where M is an integer multiple of K such that each on-off duration of the sequence of modulation samples is of the same length. The transmitter may divide the M / K samples by T, where T may represent the total number of antennas 330 (e.g., 2 or more antennas). Thus, the transmitter may generate a modulation (e.g., samples) of the sequence of modulation samples that includes on-duration 310-a, on-duration 310-b, and on-duration 310-c. Each on-duration may include a certain number M / K / T of samples of the sequence of modulation samples such that on-duration 310 is all parts of the same on-duration period of the sequence of modulation samples.

[0102] Additionally, the transmitter may generate samples such that the on-durations 310 are interleaved when transmitted via different antennas 330. Within each on-symbol of the oversampled time-domain modulation symbols (e.g., M / K symbols), the transmitter may transmit a shortened on-duration (e.g., on-duration 310) of the sequence of modulation samples with a different interleaving via each antenna 330, where the length of on-duration 310 may be 1 / T of the length of the regular on-duration of the sequence of modulation samples. That is, the transmitter may generate a signal 325-a (e.g., a first signal) for transmission via antenna 330-a and a signal 325-b (e.g., a second signal) for transmission via antenna 330-b from the sequence of modulation samples according to a transmission interleaving pattern. The transmitter may transmit signal 325-a during on-duration 310-a and transmit signal 325-b during on-duration 310-b. On-duration 310-c may not include data or may be transmitted via another antenna 330.

[0103] The transmitter may stagger the transmission of signal 325 in the time domain such that only one antenna 330 is turned on and in use at a given time. The transmitter may transmit signal 325-a via antenna 330-a and transmit signal 325-b via antenna 330-b, where signal 325 is transmitted via the respective antenna 330 at non-overlapping times or non-overlapping frequencies according to a transmission staggering pattern. For example, the on-duration 310 may be offset (e.g., different, non-overlapping) times. In some cases, the transmitter may transmit signal 325-a during a first portion of the on-duration (e.g., on-duration 310-a) of the modulated sample sequence and transmit signal 325-b during a second portion of the on-duration (e.g., on-duration 310-b) of the modulated sample sequence, where the first and second portions of the on-duration occur at non-overlapping times according to the transmission staggering pattern.

[0104] Since signal 325 is transmitted in respective portions of the on-duration, a first transmission power level associated with signal 325-a during on-duration 310-a may be equal to a second transmission power level associated with a second signal during on-duration 310-b. That is, the on-durations 310, which are part of the same on-duration period and staggered in time (resulting in one antenna 330 being activated at a given time), may increase the power of signal transmission and simplify envelope detection at the receiver.

[0105] In some cases, the transmitter may configure each signal 325 to be transmitted separately on the respective antenna 330 in the time domain or in the frequency domain. When a time-domain cyclic shift is equivalent to a frequency-domain phase ramp, the transmitter may implement the transmission staggering pattern in the frequency domain as different phase ramps. That is, the transmission staggering pattern may indicate the transmission of signals 325-a and 325-b being staggered across different frequency subbands of the resource allocation. The transmitter may generate a first signal and a second signal according to a transmission staggering pattern that indicates the application of a phase ramp in the frequency domain.

[0106] In some examples, to generate signal 325, the transmitter may use a respective transform 315 and a respective waveform generator 320 to convert each staggered modulated sample sequence (e.g., transmitted in the on-duration 310) into an OFDM waveform. For example, the transmitter may use waveform generator 320-a to convert a first staggered modulated sample sequence into a first OFDM waveform, and use waveform generator 320-b to convert a second staggered modulated sample sequence into a second OFDM waveform, where signal 325-a is generated based on the first OFDM waveform, and signal 325-b is generated based on the second OFDM waveform. In one example, waveform generator 320 may perform an N-point inverse fast Fourier transform (iFFT) algorithm on the output of transform 315 to generate the OFDM waveform, or may be another type of OFDM waveform generator.

[0107] When converting an interleaved modulation sample sequence into an OFDM waveform, the transmitter may apply corresponding transforms 315 (e.g., transform 315-a for antenna 330-a and transform 315-b for antenna 330-b) to the phase cyclic modulation sample sequence. In doing so, the transmitter may convert the time-domain signal into the frequency domain such that the first OFDM waveform and the second OFDM waveform are mapped to resources corresponding to one or more OFDM symbols. In some cases, the transform 315 may be an M-point DFT such that the OFDM waveform may be a modulation signal based on DFT-S-OFDM.

[0108] By applying spatial diversity within modulation symbols to communication with a receiver as described herein, the receiver may use an envelope detector to demodulate the signal 325. That is, although the receiver may receive the signal 325 from multiple antennas 330, the receiver may detect the overall signal across the multiple antennas 330 to detect the transmission and demodulate the transmission. Thus, for such cases of relatively high spatial diversity, the power consumption of the receiver may be the same as when the transmitter communicates with low spatial diversity.

[0109] Additionally, the signal 325 may be a low-power synchronization signal, a low-power preamble signal, a low-power wake-up signal, or any other low-power signal. The transmitter may transmit the low-power synchronization signal, the low-power preamble signal, the low-power wake-up signal, or any combination thereof via a separate channel, or the transmitter may transmit the low-power synchronization signal and the low-power preamble signal before each low-power wake-up signal transmission. The receiver may use the low-power synchronization signal, the low-power preamble signal, or both to perform time or frequency synchronization with the transmitter and to train the receiver's AGC. Thus, the low-power synchronization signal, the low-power preamble signal, or both may have the same dynamic range as the low-power wake-up signal, such as the same pre-coder cycle or the same transmission interleaving pattern.

[0110] Figure 4 An example of a transmission interleaving scheme 400 that supports spatial diversity for a low-power wake-up signal in accordance with one or more aspects of the present disclosure is illustrated. In some examples, the transmission interleaving scheme 400 may implement aspects of the wireless communication system 100, or may be implemented by aspects of the wireless communication system 100. For example, a transmitter (e.g., a wireless communication device such as a network node) may use the transmission interleaving scheme 400 to generate a signal 425 for transmission to a receiver (e.g., a wireless communication device such as a UE). In some examples, the transmitter may use the transmission interleaving scheme 400 for cases where the transmitter uses multiple antennas 430 to transmit a low-power signal (e.g., a low-power wake-up signal) to the receiver and the receiver uses a single antenna to receive the signal.

[0111] A wireless communication system can support communication between a transmitter and a receiver, which can include communication of low-power wake-up signals and other low-power signals. In some examples, the transmitter can support two or more antennas, including antenna 430-a (e.g., Tx antenna 1) and antenna 430-b (e.g., Tx antenna T, where T can represent the total number of transmit antennas). Since the receiver can be equipped with a single receive antenna, the transmitter can use transmit interleaving to design specific signals for transmission to the receiver such that the receiver can utilize different channels associated with the multiple antennas 430.

[0112] In some aspects, the transmitter can receive an information payload 405 that includes one or more bits (e.g., 1 and 0). The transmitter can modulate the one or more bits into a sequence of modulated samples for wireless transmission to the receiver via the antenna 430. The sequence of modulated samples can be a sequence of OOK-modulated samples, a sequence of ASK-modulated samples, a sequence of FSK-modulated samples, or any other sequence of samples based on low-complexity modulation. Additionally, the sequence of modulated samples, which can also be referred to as a time-domain signal, can have a length of M / K samples, where M is an integer multiple of K such that each on-off duration of the sequence of modulated samples is of the same length. The transmitter can generate subsequences 410-a, 410-b, and 410-c from the sequence of modulated samples, where each subsequence 410 includes M / K samples in its on duration.

[0113] Furthermore, the transmitter can generate the subsequences 410 such that the corresponding on durations are interleaved (e.g., the subsequences 410 can also be referred to as interleaved modulated sample sequences herein). The transmitter can divide the on duration into a number of interleaves, where each antenna 430 can use one interleave to transmit at a transmit power level (e.g., on power), while the other antennas 430 can be in an off or sleep mode. As described herein, an interleave can refer to a series of on and off durations of a modulation sequence (such as the subsequences 410), where the on duration corresponding to one antenna 430 may not overlap with any on duration corresponding to a different antenna 430. That is, the interleaving of the on durations of the subsequences 410 can be non-overlapping in time, and the transmitter can transmit the signals 425 (generated from the subsequences 410) via different antennas 430 using a transmit interleaving pattern or some cyclic shift pattern over time.

[0114] The transmitter may transmit, via antenna 430-a, a first interleaved signal 425-a (e.g., a first signal) during a first portion of the on-duration of the modulated sample sequence, and may transmit, via antenna 430-b, a second interleaved signal 425-b (e.g., a second signal) during a second portion of the on-duration of the modulated sample sequence, wherein, according to the transmission interleaving pattern, the first interleaving and the second interleaving are non-overlapping in time. In some cases, the transmitter may use a number T of interleavings to transmit T signals 425 via T corresponding antennas 430. For example, the transmitter may transmit, via antenna 430-c, a T-th interleaved signal 425-c (e.g., a T-th signal) during a T-th partition of the on-duration, and wherein the T-th interleaving may not overlap with the first interleaving and the second interleaving.

[0115] When transmitted, the signals 425 may have different sequences of on and off durations based on interleaving rather than overlapping, such that one antenna 430 may be powered on at any time. For example, signal 425-a may correspond to the sequence [x, 0, 0, x, 0, 0, x, 0, 0, 0, 0,..., 0], signal 425-b may correspond to the sequence [0, x, 0, 0, x, 0, 0, x, 0, 0, 0,..., 0], and signal 425-c may correspond to the sequence [0, 0, x, 0, 0, x, 0, 0, x, 0, 0,..., 0], where the last quarter of each sequence corresponds to the off-duration and the rest of the sequence corresponds to the on-duration.

[0116] In some examples, to generate signal 425, the transmitter may use corresponding transform 415 and corresponding waveform generator 420 to convert each interleaved modulation sample sequence (e.g., subsequence 410) into an OFDM waveform. For example, the transmitter may use waveform generator 420-a to convert the first interleaved modulation sample sequence into a first OFDM waveform, use waveform generator 420-b to convert the second interleaved modulation sample sequence into a second OFDM waveform, and use waveform generator 420-c to convert the T-th interleaved modulation sample sequence into the T-th OFDM waveform, where signal 425-a is generated based on the first OFDM waveform, signal 425-b is generated based on the second OFDM waveform, and signal 425-c is generated based on the T-th OFDM waveform. When converting the interleaved modulation sample sequence into an OFDM waveform, the transmitter may apply corresponding transform 415 (e.g., transform 415-a for antenna 430-a, transform 415-b for antenna 430-b, and transform 415-c for antenna 430-c) to the phase cyclic modulation sample sequence. In doing so, the transmitter may convert the time-domain signal into the frequency domain such that the first OFDM waveform and the second OFDM waveform are mapped to resources corresponding to one or more OFDM symbols. In some cases, transform 415 may be an M-point DFT such that the OFDM waveform may be a modulation signal based on DFT-S-OFDM. In some examples, waveform generator 420 may perform an N-point inverse fast Fourier transform (iFFT) algorithm on the output of transform 415 to generate the OFDM waveform, or may be another type of OFDM waveform generator.

[0117] Additionally, signal 425 may be a low-power synchronization signal, a low-power preamble signal, a low-power wake-up signal, or any other low-power signal. The transmitter may send the low-power synchronization signal, the low-power preamble signal, the low-power wake-up signal, or any combination thereof via a separate channel, or the transmitter may send the low-power synchronization signal and the low-power preamble signal before each low-power wake-up signal transmission. The receiver may use the low-power synchronization signal, the low-power preamble signal, or both to perform time or frequency synchronization with the transmitter and to train the receiver's AGC. Thus, the low-power synchronization signal, the low-power preamble signal, or both may have the same dynamic range as the low-power wake-up signal, e.g., the same pre-coder cycle or the same transmission interleaving pattern.

[0118] Figure 5Illustrated is an example of a transmission interleaving scheme 500 that supports spatial diversity for low-power wake-up signals in accordance with one or more aspects of the present disclosure. In some examples, the transmission interleaving scheme 500 may implement aspects of the wireless communication system 100 or may be implemented by aspects of the wireless communication system 100. For example, a transmitter (e.g., a wireless communication device such as a network node) may use the transmission interleaving scheme 500 to generate a signal 525 for transmission to a receiver (e.g., a wireless communication device such as a UE). In some examples, the transmitter may use the transmission interleaving scheme 500 for a case where the transmitter uses multiple antennas 530 to transmit a low-power signal (e.g., a low-power wake-up signal) to the receiver and the receiver uses a single antenna to receive the signal.

[0119] A wireless communication system may support communication between a transmitter and a receiver, which may include communication of low-power wake-up signals and other low-power signals. In some examples, the transmitter may support two or more antennas, including antenna 530-a (e.g., Tx antenna 1) and antenna 530-b (e.g., Tx antenna T, where T may represent the total number of transmit antennas). Since the receiver may be equipped with a single receive antenna, the transmitter may use transmission interleaving to design a particular signal for transmission to the receiver such that the receiver may exploit different channels associated with the multiple antennas 530.

[0120] In some aspects, the transmitter may receive an information payload 505 that includes one or more bits (e.g., 1s and 0s). The transmitter may modulate the one or more bits into a sequence of modulation samples 510 for wireless transmission to the receiver via the antennas 530. The sequence of modulation samples may be a sequence of OOK-modulated samples, a sequence of ASK-modulated samples, a sequence of FSK-modulated samples, or any other sequence of samples based on low-complexity modulation. Additionally, the sequence of modulation samples 510, which may also be referred to as a time-domain signal, may have a length of M / K samples, where M is an integer multiple of K such that each on-off duration of the sequence of modulation samples is of the same length.

[0121] Using a transmission interleaving pattern, the transmitter may interleave subsequences 535 of the sequence of modulation samples 510 in frequency (e.g., across different subsets of resource blocks or resource elements within a frequency resource allocation), where the subsequences 535 may be part of a low-power wake-up signal (also referred to herein as an interleaved sequence of modulation samples). To do so, the transmitter may generate a common low-power wake-up signal having a bandwidth equal to 1 / Tth of the allocated bandwidth (e.g., from the sequence of modulation samples 510, which is subsequently partitioned into subsequences 535). The transmitter may then place the subsequences 535 of the low-power wake-up signal on different subsets of resource blocks or resource elements of the frequency resource allocation for the wake-up signal resources in the frequency domain.

[0122] In some examples, to generate signal 525, the transmitter may use a corresponding transform 515 and a corresponding waveform generator 520 to convert each interleaved modulation sample sequence (e.g., subsequence 535-a, subsequence 535-b, and subsequence 535-c) into an OFDM waveform. For example, the transmitter may use waveform generator 520-a to convert the first interleaved modulation sample sequence into a first OFDM waveform, and use waveform generator 520-b to convert the second interleaved modulation sample sequence into a second OFDM waveform, where signal 525-a is generated based on the first OFDM waveform, and signal 525-b is generated based on the second OFDM waveform. When converting the interleaved modulation sample sequence into an OFDM waveform, the transmitter may apply the corresponding transform 515 (e.g., transform 515-a for antenna 530-a and transform 515-b for antenna 530-b) to the phase cyclic modulation sample sequence. In doing so, the transmitter may convert the time-domain signal into the frequency domain such that the first OFDM waveform and the second OFDM waveform are mapped to resources corresponding to one or more OFDM symbols. In some cases, transform 515 may be an M-point DFT such that the OFDM waveform may be a modulation signal based on DFT-S-OFDM. In one example, waveform generator 520 may perform an N-point inverse fast Fourier transform (iFFT) algorithm on the output of transform 515 to generate the OFDM waveform, or may be another type of OFDM waveform generator.

[0123] Additionally, signal 525 may be a low-power synchronization signal, a low-power preamble signal, a low-power wake-up signal, or any other low-power signal. The transmitter may transmit the low-power synchronization signal, the low-power preamble signal, the low-power wake-up signal, or any combination thereof via a separate channel, or the transmitter may transmit the low-power synchronization signal and the low-power preamble signal before each low-power wake-up signal transmission. The receiver may use the low-power synchronization signal, the low-power preamble signal, or both to perform time or frequency synchronization with the transmitter and to train the receiver's AGC. Thus, the low-power synchronization signal, the low-power preamble signal, or both may have the same dynamic range as the low-power wake-up signal, e.g., the same precoder loop or the same transmission interleaving pattern.

[0124] Figure 6An example of process flow 600 that supports spatial diversity for a low-power wake-up signal in accordance with one or more aspects of the present disclosure is illustrated. Process flow 600 may implement aspects of wireless communication system 100 or may be implemented by aspects of wireless communication system 100. For example, process flow 600 may illustrate operations between a transmitter 605 (e.g., a network node) and a receiver 610 (e.g., a UE), which may be examples of the corresponding devices described herein. In the following description of process flow 600, the operations between transmitter 605 and receiver 610 may be performed in an order different from the order of the example shown, or the operations performed by transmitter 605 and receiver 610 may be performed in a different order or at different times. Some operations may also be omitted from process flow 600, and other operations may be added to process flow 600.

[0125] At 615, transmitter 605 may modulate one or more bits into a sequence of modulation samples for wireless transmission to receiver 610. In some examples, the sequence of modulation samples may include a sequence of time-domain samples of bits (e.g., 0s and 1s), where the value of a bit may represent an on duration (e.g., a bit having a value of 1) or an off duration (e.g., a bit having a value of 0). The sequence of modulation samples may be an OOK modulation sample sequence, an ASK modulation sample sequence, or an FSK modulation sample sequence.

[0126] At 620, transmitter 605 may apply a first phase cycling pattern to a set of subsequences of the sequence of modulation samples to generate a first phase-cycled modulation sample sequence for transmission via a first transmit antenna. For example, transmitter 605 may multiply a first subsequence of the set of subsequences by a first phase of the first phase cycling pattern for the first transmit antenna.

[0127] At 625, transmitter 605 may apply a second phase cycling pattern to a set of subsequences of the sequence of modulation samples to generate a second phase-cycled modulation sample sequence for transmission via a second transmit antenna. For example, transmitter 605 may multiply a first subsequence of the set of subsequences by a second phase of the second phase cycling pattern for the second transmit antenna, where the first phase and the second phase may be different. Additionally, the transmitter may apply the first phase cycling pattern and the second phase cycling pattern to the same bits of the sequence of modulation samples for each antenna.

[0128] At 630, the transmitter 605 may transmit a first signal to the receiver 610 via a first transmit antenna based on a first phase cyclic modulation sample sequence. At 635, the transmitter 605 may transmit a second signal to the receiver 610 via a second transmit antenna based on a second phase cyclic modulation sample sequence. The first signal and the second signal may be low-power synchronization signals or low-power preamble signals. Additionally, based on the phase cyclic pattern, the transmissions of the first antenna and the second antenna may be non-overlapping in time. The receiver 610 may receive the first signal and the second signal and demodulate the overall signal using envelope detection.

[0129] Figure 7 An example of a process flow 700 that supports spatial diversity for low-power wake-up signals in accordance with one or more aspects of the present disclosure is illustrated. The process flow 700 may implement aspects of the wireless communication system 100 or may be implemented by aspects of the wireless communication system 100. For example, the process flow 700 may illustrate operations between a transmitter 705 (e.g., a network node) and a receiver 710 (e.g., a UE), which may be examples of the corresponding devices described herein. In the following description of the process flow 700, the operations between the transmitter 705 and the receiver 710 may be performed in an order different from the illustrated example order, or the operations performed by the transmitter 705 and the receiver 710 may be performed in a different order or at different times. Some operations may also be omitted from the process flow 700, and other operations may be added to the process flow 700.

[0130] At 715, the transmitter 705 may modulate one or more bits into a modulation sample sequence for wireless transmission to the receiver. In some examples, the modulation sample sequence may include a time-domain sample sequence of bits (e.g., 0s and 1s), where the value of a bit may represent an on duration (e.g., a bit having a value of 1) or an off duration (e.g., a bit having a value of 0). The modulation sample sequence may be an OOK modulation sample sequence, an ASK modulation sample sequence, or an FSK modulation sample sequence.

[0131] At 720, the transmitter 705 may generate a first signal for transmission via a first transmit antenna and a second signal for transmission via a second transmit antenna from the modulation sample sequence according to a transmit interleaving pattern. In some examples, the transmit interleaving pattern may indicate interleaving the transmissions of the first signal and the second signal across different frequency subbands of a resource allocation. Additionally or alternatively, the transmit interleaving pattern may indicate applying a phase ramp in the frequency domain to generate the first signal and the second signal.

[0132] At 725, the transmitter 705 may transmit a first signal to the receiver 710 via a first transmit antenna and a second signal to the receiver via a second transmit antenna, where the first signal and the second signal are transmitted via the first transmit antenna and the second transmit antenna, respectively, at non-overlapping times or via non-overlapping frequencies according to a transmit interleaving pattern. The receiver 710 may receive the first signal and the second signal and demodulate the overall signal using envelope detection.

[0133] Figure 8 Block diagram 800 illustrates an apparatus 805 that supports spatial diversity for low-power wake-up signals in accordance with one or more aspects of the present disclosure. The apparatus 805 may be an example of aspects of a transmitter as described herein. The apparatus 805 may include a receiver 810, a transmitter 815, and a communication manager 820. The apparatus 805 may also include one or more processors, a memory coupled to the one or more processors, and instructions stored in the memory that are executable by the one or more processors to enable the one or more processors to perform the signal modulation features discussed herein. Each of these components may communicate with each other (e.g., via one or more buses).

[0134] The receiver 810 may provide components for obtaining (e.g., receiving, determining, identifying) information associated with various channels (e.g., control channels, data channels, information channels, channels associated with a protocol stack) such as user data, control information, or any combination thereof (e.g., I / Q samples, symbols, packets, protocol data units, service data units). The information may be passed to other components of the apparatus 805. In some examples, the receiver 810 may support obtaining information by receiving signals via one or more antennas. Additionally or alternatively, the receiver 810 may support obtaining information by receiving signals via one or more wired (e.g., electrical, fiber optic) interfaces, wireless interfaces, or any combination thereof.

[0135] The transmitter 815 may provide a component for outputting (e.g., transmitting, providing, conveying, delivering) information generated by other components of the device 805. For example, the transmitter 815 may output information associated with various channels (e.g., control channels, data channels, information channels, channels associated with a protocol stack) such as user data, control information, or any combination thereof (e.g., I / Q samples, symbols, packets, protocol data units, service data units). In some examples, the transmitter 815 may support outputting information by transmitting signals via one or more antennas. Additionally or alternatively, the transmitter 815 may support outputting information by transmitting signals via one or more wired (e.g., electrical, optical fiber) interfaces, wireless interfaces, or any combination thereof. In some examples, the transmitter 815 and the receiver 810 may be co-located in a transceiver, which may include a modem or be coupled to a modem.

[0136] The communication manager 820, the receiver 810, the transmitter 815, or various combinations thereof, or various components thereof, may be examples of components for performing various aspects of spatial diversity for low-power wake-up signals as described herein. For example, the communication manager 820, the receiver 810, the transmitter 815, or various combinations or components thereof may support methods for performing one or more of the functions described herein.

[0137] In some examples, the communication manager 820, the receiver 810, the transmitter 815, or various combinations or components thereof may be implemented in hardware (e.g., in a communication management circuit). The hardware may include a processor, a DSP, a CPU, an ASIC, an FPGA, or other programmable logic device, a microcontroller, discrete gate or transistor logic components, discrete hardware components, or any combination thereof configured to or otherwise supporting components for performing the functions described in this disclosure. In some examples, the processor and the memory coupled to the processor may be configured to perform one or more of the functions described herein (e.g., by the processor executing instructions stored in the memory).

[0138] Additionally or alternatively, in some examples, the communication manager 820, the receiver 810, the transmitter 815, or various combinations or components thereof may be implemented in code executed by a processor (e.g., implemented as communication management software or firmware). If implemented in code executed by a processor, the functions of the communication manager 820, the receiver 810, the transmitter 815, or various combinations or components thereof may be performed by a general-purpose processor, a DSP, a CPU, an ASIC, an FPGA, a microcontroller, or any combination of these or other programmable logic devices configured to or otherwise supporting components for performing the functions described in this disclosure.

[0139] In some examples, the communication manager 820 may be configured to use or otherwise cooperate with the receiver 810, the transmitter 815, or both to perform various operations (e.g., receive, obtain, monitor, output, transmit). For example, the communication manager 820 may receive information from the receiver 810, convey information to the transmitter 815, or integrate in combination with the receiver 810, the transmitter 815, or both to obtain information, output information, or perform various other operations as described herein.

[0140] According to examples disclosed herein, the communication manager 820 may support wireless communication at the transmitter. For example, the communication manager 820 may be configured to or otherwise support components for modulating one or more bits into a sequence of modulation samples for wireless transmission to a receiver. The communication manager 820 may be configured to or otherwise support components for applying a first phase cycling pattern to a plurality of subsequences of the sequence of modulation samples to generate a first phase cycled modulation sample sequence for transmission via a first transmit antenna. The communication manager 820 may be configured to or otherwise support components for applying a second phase cycling pattern to the plurality of subsequences of the sequence of modulation samples to generate a second phase cycled modulation sample sequence for transmission via a second transmit antenna. The communication manager 820 may be configured to or otherwise support components for transmitting a first signal via the first transmit antenna based on the first phase cycled modulation sample sequence. The communication manager 820 may be configured to or otherwise support components for transmitting a second signal via the second transmit antenna based on the second phase cycled modulation sample sequence.

[0141] Additionally or alternatively, according to examples disclosed herein, the communication manager 820 may support wireless communication at the transmitter. For example, the communication manager 820 may be configured to or otherwise support components for modulating one or more bits into a sequence of modulation samples for wireless transmission to a receiver. The communication manager 820 may be configured to or otherwise support components for generating a first signal for transmission via a first transmit antenna and a second signal for transmission via a second transmit antenna from the sequence of modulation samples according to a transmit interleaving pattern. The communication manager 820 may be configured to or otherwise support components for transmitting the first signal via the first transmit antenna and the second signal via the second transmit antenna, where the first signal and the second signal are transmitted via the first transmit antenna and the second transmit antenna, respectively, at non-overlapping times or via non-overlapping frequencies according to the transmit interleaving pattern.

[0142] By including or configuring a communication manager 820 according to an example as described herein, a device 805 (e.g., a processor that controls a receiver 810, a transmitter 815, a communication manager 820, or a combination thereof or otherwise coupled to them) may support techniques for transmitting low-power signals according to a phase cycling pattern or a transmit interleaving pattern, which may increase spatial diversity and reduce power consumption at the receiver.

[0143] Figure 9 Block diagram 900 illustrates a device 905 that supports spatial diversity for low-power wake-up signals in accordance with one or more aspects of the present disclosure. Device 905 may be an example of aspects of device 805 or transmitter 115 as described herein. Device 905 may include a receiver 910, a transmitter 915, and a communication manager 920. Device 905 may also include a processor. Each of these components may communicate with one another (e.g., via one or more buses).

[0144] The receiver 910 may provide components for obtaining (e.g., receiving, determining, identifying) information associated with various channels (e.g., control channels, data channels, information channels, channels associated with a protocol stack) such as user data, control information, or any combination thereof (e.g., I / Q samples, symbols, packets, protocol data units, service data units). The information may be passed to other components of device 905. In some examples, the receiver 910 may support obtaining information by receiving signals via one or more antennas. Additionally or alternatively, the receiver 910 may support obtaining information by receiving signals via one or more wired (e.g., electrical, fiber optic) interfaces, wireless interfaces, or any combination thereof.

[0145] The transmitter 915 may provide components for outputting (e.g., transmitting, providing, conveying, delivering) information generated by other components of device 905. For example, the transmitter 915 may output information associated with various channels (e.g., control channels, data channels, information channels, channels associated with a protocol stack) such as user data, control information, or any combination thereof (e.g., I / Q samples, symbols, packets, protocol data units, service data units). In some examples, the transmitter 915 may support outputting information by transmitting signals via one or more antennas. Additionally or alternatively, the transmitter 915 may support outputting information by transmitting signals via one or more wired (e.g., electrical, fiber optic) interfaces, wireless interfaces, or any combination thereof. In some examples, the transmitter 915 and the receiver 910 may be co-located in a transceiver that may include a modem or be coupled to a modem.

[0146] Device 905 or its various components can be examples of components for performing aspects of spatial diversity for low-power wake-up signals as described herein. For example, communication manager 920 can include modulation component 925, phase cycling component 930, signal component 935, transmit interleaving component 940, or any combination thereof. Communication manager 920 can be an example of aspects of communication manager 820 as described herein. In some examples, communication manager 920 or its various components can be configured to perform various operations (e.g., receive, obtain, monitor, output, transmit) using or otherwise in cooperation with receiver 910, transmitter 915, or both. For example, communication manager 920 can receive information from receiver 910, convey information to transmitter 915, or integrate in combination with receiver 910, transmitter 915, or both to obtain information, output information, or perform various other operations as described herein.

[0147] According to examples disclosed herein, communication manager 920 can support wireless communication at a transmitter. Modulation component 925 can be configured to or otherwise support components for modulating one or more bits into a sequence of modulation samples for wireless transmission to a receiver. Phase cycling component 930 can be configured to or otherwise support components for applying a first phase cycling pattern to a set of multiple subsequences of the sequence of modulation samples to generate a first phase cycled modulation sample sequence for transmission via a first transmit antenna. Phase cycling component 930 can be configured to or otherwise support components for applying a second phase cycling pattern to the set of multiple subsequences of the sequence of modulation samples to generate a second phase cycled modulation sample sequence for transmission via a second transmit antenna. Signal component 935 can be configured to or otherwise support components for transmitting a first signal via the first transmit antenna based on the first phase cycled modulation sample sequence. Signal component 935 can be configured to or otherwise support components for transmitting a second signal via the second transmit antenna based on the second phase cycled modulation sample sequence.

[0148] Additionally or alternatively, according to an example as disclosed herein, the communication manager 920 may support wireless communication at the transmitter. The modulation component 925 may be configured to or otherwise support components for modulating one or more bits into a sequence of modulation samples for wireless transmission to a receiver. The transmit interleaving component 940 may be configured to or otherwise support components for generating a first signal for transmission via a first transmit antenna and a second signal for transmission via a second transmit antenna from the sequence of modulation samples according to a transmit interleaving pattern. The signal component 935 may be configured to or otherwise support components for transmitting the first signal via the first transmit antenna and the second signal via the second transmit antenna, where the first signal and the second signal are transmitted via the first transmit antenna and the second transmit antenna, respectively, at non-overlapping times or via non-overlapping frequencies according to the transmit interleaving pattern.

[0149] In some cases, the modulation component 925, the phase cycling component 930, the signal component 935, and the transmit interleaving component 940 may each be a processor (e.g., a transceiver processor, or a radio processor, or a transmitter processor, or a receiver processor) or at least a part of a processor. The processor may be coupled to a memory and execute instructions stored in the memory that enable the processor to perform or facilitate the features of the modulation component 925, the phase cycling component 930, the signal component 935, and the transmit interleaving component 940 discussed herein. The transceiver processor may be co-located with and / or communicate with (e.g., direct the operation of) the transceiver of the device. The radio processor may be co-located with and / or communicate with (e.g., direct the operation of) the radio components of the device (e.g., NR radio components, LTE radio components, Wi-Fi radio components). The transmitter processor may be co-located with and / or communicate with (e.g., direct the operation of) the transmitter of the device. The receiver processor may be co-located with and / or communicate with (e.g., direct the operation of) the receiver of the device.

[0150] Figure 10FIG. 1000 is a block diagram illustrating a communication manager 1020 that supports spatial diversity for low power wake-up signals in accordance with one or more aspects of the present disclosure. The communication manager 1020 may be an example of aspects of the communication manager 820, the communication manager 920, or both as described herein. The communication manager 1020 or its various components may be examples of components for performing various aspects of spatial diversity for low power wake-up signals as described herein. For example, the communication manager 1020 may include a modulation component 1025, a phase cycling component 1030, a signal component 1035, a transmit interleaving component 1040, a phase component 1045, an OFDM waveform component 1050, an on-duration component 1055, an interleaving component 1060, a subband component 1065, or any combination thereof. Each of these components may communicate directly or indirectly with each other (e.g., via one or more buses).

[0151] In accordance with an example as disclosed herein, the communication manager 1020 may support wireless communication at a transmitter. The modulation component 1025 may be configured to or otherwise support components for modulating one or more bits into a sequence of modulation samples for wireless transmission to a receiver. The phase cycling component 1030 may be configured to or otherwise support components for applying a first phase cycling pattern to a plurality of subsequences of the sequence of modulation samples to generate a first phase cycled modulation sample sequence for transmission via a first transmit antenna. In some examples, the phase cycling component 1030 may be configured to or otherwise support components for applying a second phase cycling pattern to the plurality of subsequences of the sequence of modulation samples to generate a second phase cycled modulation sample sequence for transmission via a second transmit antenna. The signal component 1035 may be configured to or otherwise support components for transmitting a first signal via the first transmit antenna based on the first phase cycled modulation sample sequence. In some examples, the signal component 1035 may be configured to or otherwise support components for transmitting a second signal via the second transmit antenna based on the second phase cycled modulation sample sequence.

[0152] In some examples, the phase component 1045 may be configured to or otherwise support components for multiplying a first subsequence of the plurality of subsequences by a first phase of the first phase cycling pattern for the first transmit antenna and multiplying the first subsequence of the plurality of subsequences by a second phase of the second phase cycling pattern for the second transmit antenna, where the first phase is different from the second phase.

[0153] In some examples, the phase cycling component 1030 may be configured to or otherwise support components for applying the first phase cycling pattern to a first bit of the sequence of modulation samples and applying the second phase cycling pattern to the first bit of the sequence of modulation samples.

[0154] In some examples, the OFDM waveform component 1050 may be configured to or otherwise support components for converting a first phase-cycled modulation sample sequence into a first OFDM waveform and a second phase-cycled modulation sample sequence into a second OFDM waveform, where a first signal is generated based on the first OFDM waveform and a second signal is generated based on the second OFDM waveform.

[0155] In some examples, the first OFDM waveform and the second OFDM waveform are mapped to resources corresponding to a single OFDM symbol.

[0156] In some examples, the first OFDM waveform and the second OFDM waveform are mapped to resources corresponding to a set of multiple OFDM symbols.

[0157] In some examples, the first signal and the second signal are associated with zero mean. In some examples, the first phase-cycled modulation sample sequence and the second phase-cycled modulation sample sequence are each associated with zero mean.

[0158] In some examples, the first signal and the second signal include a low-power synchronization signal, a low-power preamble signal, a low-power wake-up signal, or any combination thereof. In some examples, the modulation sample sequence includes an OOK sample sequence, an ASK sample sequence, or an FSK sample sequence.

[0159] Additionally or alternatively, according to examples disclosed herein, the communication manager 1020 may support wireless communication at a transmitter. In some examples, the modulation component 1025 may be configured to or otherwise support components for modulating one or more bits into a modulation sample sequence for wireless transmission to a receiver. The transmit interleaving component 1040 may be configured to or otherwise support components for generating a first signal for transmission via a first transmit antenna and a second signal for transmission via a second transmit antenna from the modulation sample sequence according to a transmit interleaving pattern. In some examples, the signal component 1035 may be configured to or otherwise support components for transmitting the first signal via the first transmit antenna and the second signal via the second transmit antenna, where the first signal and the second signal are transmitted via the first transmit antenna and the second transmit antenna, respectively, at non-overlapping times or via non-overlapping frequencies according to a transmit interleaving pattern. In some examples, the transmit interleaving pattern indicates interleaving the transmission of the first signal and the second signal across different frequency subbands of a resource allocation.

[0160] In some examples, to support the transmission of a first signal and a second signal, the on-duration component 1055 may be configured to or otherwise support a component for transmitting the first signal during a first portion of the on-duration of the modulated sample sequence and transmitting the second signal during a second portion of the on-duration of the modulated sample sequence, wherein according to the transmission interleaving pattern, the first portion and the second portion of the on-duration occur at non-overlapping times.

[0161] In some examples, a first transmission power level associated with the first signal during the first portion of the on-duration is equal to a second transmission power level associated with the second signal during the second portion of the on-duration.

[0162] In some examples, to support the transmission of a first signal and a second signal, the interleaving component 1060 may be configured to or otherwise support a component for transmitting the first signal as a first interleaving during a first portion of the on-duration of the modulated sample sequence and transmitting the second signal as a second interleaving during a second portion of the on-duration of the modulated sample sequence, wherein according to the transmission interleaving pattern, the first interleaving and the second interleaving are non-overlapping in time.

[0163] In some examples, the sub-band component 1065 may be configured to or otherwise support a component for transmitting the first signal via a first transmit antenna in a first sub-band of the allocated bandwidth and transmitting the second signal via a second transmit antenna using a second sub-band of the allocated bandwidth, wherein the first sub-band is different from the second sub-band.

[0164] In some examples, to support the generation of a first signal and a second signal, the transmission interleaving component 1040 may be configured to or otherwise support a component for generating the first signal and the second signal according to a transmission interleaving pattern indicating the application of a phase ramp in the frequency domain.

[0165] In some examples, the OFDM waveform component 1050 may be configured to or otherwise support a component for converting a first interleaved modulated sample sequence into a first OFDM waveform and converting a second interleaved modulated sample sequence into a second OFDM waveform, wherein the first signal is generated based on the first OFDM waveform and the second signal is generated based on the second OFDM waveform.

[0166] In some examples, the first OFDM waveform and the second OFDM waveform are mapped to resources corresponding to a single OFDM symbol.

[0167] In some examples, the first OFDM waveform and the second OFDM waveform are mapped to resources corresponding to a set of multiple OFDM symbols.

[0168] In some examples, the first signal and the second signal include a low-power synchronization signal, a low-power preamble signal, a low-power wake-up signal, or any combination thereof. In some examples, the modulated sample sequence includes an OOK sample sequence, an ASK sample sequence, or an FSK sample sequence.

[0169] In some cases, the modulation component 1025, the phase cycling component 1030, the signal component 1035, the transmit interleaving component 1040, the phase component 1045, the OFDM waveform component 1050, the on-duration component 1055, the interleaving component 1060, and the sub-band component 1065 can each be a processor (e.g., a transceiver processor, or a radio processor, or a transmitter processor, or a receiver processor) or at least a part of a processor. The processor can be coupled to a memory and execute instructions stored in the memory that enable the processor to perform or facilitate the features of the modulation component 1025, the phase cycling component 1030, the signal component 1035, the transmit interleaving component 1040, the phase component 1045, the OFDM waveform component 1050, the on-duration component 1055, the interleaving component 1060, and the sub-band component 1065 discussed herein.

[0170] Figure 11 FIG. illustrates a system 1100 including a device 1105 that supports spatial diversity for a low-power wake-up signal, in accordance with one or more aspects of the present disclosure. The device 1105 can be an example of the device 805, the device 905, or a transmitter as described herein or can include components of these devices. The device 1105 can include components for two-way voice and data communication, which include components for sending and receiving communications, such as a communication manager 1120, a transceiver 1110, an antenna 1115, a memory 1125, code 1130, and a processor 1135. These components can communicate electronically via one or more buses (e.g., bus 1140) or otherwise be coupled (e.g., operatively, communicatively, functionally, electronically, electrically).

[0171] As described herein, the transceiver 1110 may support bidirectional communication via a wired link, a wireless link, or both. In some examples, the transceiver 1110 may include a wired transceiver and may communicate bidirectionally with another wired transceiver. Additionally or alternatively, in some examples, the transceiver 1110 may include a wireless transceiver and may communicate bidirectionally with another wireless transceiver. In some examples, the device 1105 may include one or more antennas 1115, which may be capable of sending or receiving wireless transmissions (e.g., concurrently). The transceiver 1110 may also include a modem for: modulating a signal, providing the modulated signal for transmission (e.g., via one or more antennas 1115, via a wired transmitter), receiving a modulated signal (e.g., from one or more antennas 1115, from a wired receiver), and demodulating a signal. In some implementations, the transceiver 1110 may include one or more interfaces, such as one or more interfaces coupled to one or more antennas 1115 configured to support various receiving or obtaining operations, or one or more interfaces coupled to one or more antennas 1115 configured to support various transmitting or outputting operations, or a combination thereof. In some implementations, the transceiver 1110 may include or be configured to be coupled to one or more processors or memory components that are operable to: perform or support operations based on received or obtained information or signals; or generate information or other signals for transmission or other output, or any combination thereof. In some implementations, the transceiver 1110 or the transceiver 1110 and one or more antennas 1115 or the transceiver 1110 and one or more antennas 1115 and one or more processors or memory components (e.g., processor 1135 or memory 1125 or both) may be included in a chip or chip assembly installed in the device 1105. In some examples, the transceiver may be operable to support communications via one or more communication links (eg, communication link 125, backhaul communication link 120, midhaul communication link 162, fronthaul communication link 168).

[0172] Memory 1125 may include RAM and ROM. Memory 1125 may store computer-readable, computer-executable code 1130 including instructions that, when executed by processor 1135, cause device 1105 to perform various functions described herein. Code 1130 may be stored in a non-transitory computer-readable medium such as system memory or another type of memory. In some cases, code 1130 may not be directly executable by processor 1135, but may (e.g., when compiled and executed) cause a computer to perform the functions described herein. In some cases, memory 1125 may also include, among other things, a BIOS that may control basic hardware or software operations, such as interaction with peripheral components or devices.

[0173] Processor 1135 may include intelligent hardware devices (e.g., general-purpose processors, DSPs, ASICs, CPUs, FPGAs, microcontrollers, programmable logic devices, discrete gate or transistor logic components, discrete hardware components, or any combination thereof). In some cases, processor 1135 may be configured to operate a memory array using a memory controller. In some other cases, the memory controller may be integrated into processor 1135. Processor 1135 may be configured to execute computer-readable instructions stored in a memory (e.g., memory 1125) to cause device 1105 to perform various functions (e.g., functions or tasks supporting spatial diversity for low-power wake-up signals). For example, device 1105 or components of device 1105 may include processor 1135 and memory 1125 coupled to processor 1135, and processor 1135 and memory 1125 are configured to perform the various functions described herein. Processor 1135 may be an example of a cloud computing platform (e.g., one or more physical nodes and supporting software, such as an operating system, virtual machine, or container instance) that may (e.g., by executing code 1130) host functions for performing the functions of device 1105. Processor 1135 may be any one or more suitable processors capable of executing scripts or instructions of one or more software programs stored in device 1105 (such as within memory 1125). In some specific implementations, processor 1135 may be a component of a processing system. A processing system generally may refer to a system or series of machines or components that receive inputs and process these inputs to produce a set of outputs (the set of outputs may be passed to other systems or components of, for example, device 1105). For example, the processing system of device 1105 may refer to a system that includes various other components or sub-components of device 1105, such as processor 1135 or transceiver 1110 or communication manager 1120 or a combination of other components or components of device 1105. The processing system of device 1105 may interface with other components of device 1105 and may process information (such as inputs or signals) received from other components or output information to other components. For example, a chip or modem of device 1105 may include a processing system and one or more interfaces for outputting information or for obtaining information or both. The one or more interfaces may be implemented as or otherwise include a first interface configured to output information and a second interface configured to obtain information, or the same interface configured to output information and obtain information, and other specific implementations. In some specific implementations, the one or more interfaces may refer to an interface between the processing system of the chip or modem and a transmitter such that device 1105 may transmit information output from the chip or modem.Additionally or alternatively, in some embodiments, the one or more interfaces may refer to an interface between a processing system of a chip or modem and a receiver, such that the device 1105 can obtain information or signal input, and the information can be passed to the processing system. One of ordinary skill in the art will readily recognize that the first interface may also obtain information or signal input, and the second interface may also output information or signal output.

[0174] In some examples, the bus 1140 may support communication within a protocol layer of a protocol stack (e.g., within the protocol layer). In some examples, the bus 1140 may support communication associated with a logical channel of a protocol stack (e.g., between protocol layers of the protocol stack), which may include communication performed within components of the device 1105, or communication performed between different components of the device 1105 that may be co-located or located at different locations (e.g., where the device 1105 may refer to a system in which one or more of the communication manager 1120, transceiver 1110, memory 1125, code 1130, and processor 1135 may be located in one component or divided among different components).

[0175] In some examples, the communication manager 1120 may manage aspects of communication with the core network 130 (e.g., via one or more wired or wireless backhaul links). For example, the communication manager 1120 may manage the delivery of data communication for client devices such as one or more UEs 115. In some examples, the communication manager 1120 may manage communication with other network entities 105, and may include a controller or scheduler for coordinating with other network entities 105 to control communication with the UEs 115. In some examples, the communication manager 1120 may support the X2 interface within the LTE / LTE-A wireless communication network technology to provide communication between network entities 105.

[0176] According to an example as disclosed herein, communication manager 1120 may support wireless communication at a transmitter. For example, communication manager 1120 may be configured to or otherwise support components for modulating one or more bits into a sequence of modulation samples for wireless transmission to a receiver. Communication manager 1120 may be configured to or otherwise support components for applying a first phase cycling pattern to a plurality of subsequences of the sequence of modulation samples to generate a first phase-cycled modulation sample sequence for transmission via a first transmit antenna. Communication manager 1120 may be configured to or otherwise support components for applying a second phase cycling pattern to the plurality of subsequences of the sequence of modulation samples to generate a second phase-cycled modulation sample sequence for transmission via a second transmit antenna. Communication manager 1120 may be configured to or otherwise support components for transmitting a first signal via the first transmit antenna based on the first phase-cycled modulation sample sequence. Communication manager 1120 may be configured to or otherwise support components for transmitting a second signal via the second transmit antenna based on the second phase-cycled modulation sample sequence.

[0177] Additionally or alternatively, according to an example as disclosed herein, communication manager 1120 may support wireless communication at a transmitter. For example, communication manager 1120 may be configured to or otherwise support components for modulating one or more bits into a sequence of modulation samples for wireless transmission to a receiver. Communication manager 1120 may be configured to or otherwise support components for generating a first signal for transmission via a first transmit antenna and a second signal for transmission via a second transmit antenna from the sequence of modulation samples according to a transmit interleaving pattern. Communication manager 1120 may be configured to or otherwise support components for transmitting the first signal via the first transmit antenna and the second signal via the second transmit antenna, where the first signal and the second signal are transmitted via the first transmit antenna and the second transmit antenna, respectively, at non-overlapping times or via non-overlapping frequencies according to the transmit interleaving pattern.

[0178] By including or configuring communication manager 1120 according to an example as described herein, device 1105 may support techniques for a transmit interleaving pattern that may increase spatial diversity and reduce power consumption at the device.

[0179] In some examples, the communication manager 1120 may be configured to perform various operations (e.g., receive, obtain, monitor, output, transmit) using or otherwise in cooperation with the transceiver 1110, one or more antennas 1115 (e.g., where applicable), or any combination thereof. Although the communication manager 1120 is illustrated as a separate component, in some examples, one or more of the functions described with reference to the communication manager 1120 may be supported or performed by the transceiver 1110, the processor 1135, the memory 1125, the code 1130, or any combination thereof. For example, the code 1130 may include instructions that may be executed by the processor 1135 to cause the device 1105 to perform various aspects of spatial diversity for low-power wake-up signals as described herein, or the processor 1135 and the memory 1125 may otherwise be configured to perform or support such operations.

[0180] Figure 12 A flowchart illustrating a method 1200 that supports spatial diversity for low-power wake-up signals in accordance with one or more aspects of the present disclosure is shown. Operations of the method 1200 may be implemented by a transmitter or its components as described herein. For example, operations of the method 1200 may be performed by a transmitter as described with reference to Figures 1 to 11 as described. In some examples, the transmitter may execute an instruction set to control functional elements of the transmitter to perform the described functions. Additionally or alternatively, the transmitter may use dedicated hardware to perform aspects of the described functions.

[0181] At 1205, the method may include modulating one or more bits into a sequence of modulation samples for wireless transmission to a receiver. The operation at 1205 may be performed in accordance with examples disclosed herein. In some examples, aspects of the operation at 1205 may be performed by a modulation component 1025 as described with reference to Figure 10 as described.

[0182] At 1210, the method may include applying a first phase cycling pattern to a set of multiple subsequences of the sequence of modulation samples to generate a first phase-cycled modulation sample sequence for transmission via a first transmit antenna. The operation at 1210 may be performed in accordance with examples disclosed herein. In some examples, aspects of the operation at 1210 may be performed by a phase cycling component 1030 as described with reference to Figure 10 as described.

[0183] At 1215, the method may include applying a second phase cycling pattern to the set of multiple subsequences of the sequence of modulation samples to generate a second phase-cycled modulation sample sequence for transmission via a second transmit antenna. The operation at 1215 may be performed in accordance with examples disclosed herein. In some examples, aspects of the operation at 1215 may be performed by a phase cycling component 1030 as described with reference to Figure 10performed by the described phase cycling component 1030.

[0184] At 1220, the method may include transmitting a first signal via a first transmit antenna based on a first phase cycling modulation sample sequence. The operation of 1220 may be performed in accordance with the examples disclosed herein. In some examples, aspects of the operation of 1220 may be performed by the signal component 1035 as described with reference to Figure 10 the described signal component 1035.

[0185] At 1225, the method may include transmitting a second signal via a second transmit antenna based on a second phase cycling modulation sample sequence. The operation of 1225 may be performed in accordance with the examples disclosed herein. In some examples, aspects of the operation of 1225 may be performed by the signal component 1035 as described with reference to Figure 10 the described signal component 1035.

[0186] Figure 13 illustrates a flowchart of a method 1300 that supports spatial diversity for a low-power wake-up signal in accordance with one or more aspects of the present disclosure. The operations of method 1300 may be implemented by a transmitter or its components as described herein. For example, the operations of method 1300 may be performed by a transmitter as described with reference to Figures 1 to 11 the described transmitter. In some examples, the transmitter may execute an instruction set to control functional elements of the transmitter to perform the described functions. Additionally or alternatively, the transmitter may use dedicated hardware to perform aspects of the described functions.

[0187] At 1305, the method may include modulating one or more bits into a modulation sample sequence for wireless transmission to a receiver. The operation of 1305 may be performed in accordance with the examples disclosed herein. In some examples, aspects of the operation of 1305 may be performed by the modulation component 1025 as described with reference to Figure 10 the described modulation component 1025.

[0188] At 1310, the method may include multiplying a first subsequence of the plurality of subsequences by a first phase of a first phase cycling pattern for a first transmit antenna and multiplying the first subsequence of the plurality of subsequences by a second phase of a second phase cycling pattern for a second transmit antenna, wherein the first phase is different from the second phase. The operation of 1310 may be performed in accordance with the examples disclosed herein. In some examples, aspects of the operation of 1310 may be performed by the phase component 1045 as described with reference to Figure 10 the described phase component 1045.

[0189] At 1315, the method may include transmitting a first signal via a first transmit antenna based on a first phase cycling modulation sample sequence. The operation of 1315 may be performed in accordance with the examples disclosed herein. In some examples, aspects of the operation of 1315 may be performed by a reference as described with reference toFigure 10 performed by the described signal component 1035.

[0190] At 1320, the method may include transmitting a second signal via a second transmit antenna based on a second phase cyclic modulation sample sequence. The operation of 1320 may be performed in accordance with the examples disclosed herein. In some examples, aspects of the operation of 1320 may be performed by the signal component 1035 as described with reference to Figure 10 performed by the described signal component 1035.

[0191] Figure 14 illustrates a flowchart of a method 1400 that supports spatial diversity for low-power wake-up signals in accordance with one or more aspects of the present disclosure. The operations of method 1400 may be implemented by a transmitter or its components as described herein. For example, the operations of method 1400 may be performed by a transmitter as described with reference to Figures 1 to 11 performed by the described transmitter. In some examples, the transmitter may execute an instruction set to control functional elements of the transmitter to perform the described functions. Additionally or alternatively, the transmitter may use dedicated hardware to perform aspects of the described functions.

[0192] At 1405, the method may include modulating one or more bits into a modulation sample sequence for wireless transmission to a receiver. The operation of 1405 may be performed in accordance with the examples disclosed herein. In some examples, aspects of the operation of 1405 may be performed by the modulation component 1025 as described with reference to Figure 10 performed by the described modulation component 1025.

[0193] At 1410, the method may include applying a first phase cyclic pattern to a set of multiple subsequences of the modulation sample sequence to generate a first phase cyclic modulation sample sequence for transmission via a first transmit antenna. The operation of 1410 may be performed in accordance with the examples disclosed herein. In some examples, aspects of the operation of 1410 may be performed by the phase cyclic component 1030 as described with reference to Figure 10 performed by the described phase cyclic component 1030.

[0194] At 1415, the method may include applying a second phase cyclic pattern to the set of multiple subsequences of the modulation sample sequence to generate a second phase cyclic modulation sample sequence for transmission via a second transmit antenna. The operation of 1415 may be performed in accordance with the examples disclosed herein. In some examples, aspects of the operation of 1415 may be performed by the phase cyclic component 1030 as described with reference to Figure 10 performed by the described phase cyclic component 1030.

[0195] At 1420, the method may include converting a first phase cyclic modulation sample sequence into a first OFDM waveform and converting a second phase cyclic modulation sample sequence into a second OFDM waveform, wherein a first signal is generated based on the first OFDM waveform, and a second signal is generated based on the second OFDM waveform. The operations at 1420 may be performed according to the examples disclosed herein. In some examples, aspects of the operations at 1420 may be performed by the OFDM waveform component 1050 as described with reference to Figure 10 The OFDM waveform component 1050 described above.

[0196] At 1425, the method may include transmitting a first signal via a first transmit antenna based on the first phase cyclic modulation sample sequence. The operations at 1425 may be performed according to the examples disclosed herein. In some examples, aspects of the operations at 1425 may be performed by the signal component 1035 as described with reference to Figure 10 The signal component 1035 described above.

[0197] At 1430, the method may include transmitting a second signal via a second transmit antenna based on the second phase cyclic modulation sample sequence. The operations at 1430 may be performed according to the examples disclosed herein. In some examples, aspects of the operations at 1430 may be performed by the signal component 1035 as described with reference to Figure 10 The signal component 1035 described above.

[0198] Figure 15 Illustrates a flowchart of a method 1500 that supports spatial diversity for a low-power wake-up signal in accordance with one or more aspects of the present disclosure. The operations of method 1500 may be implemented by a transmitter or its components as described herein. For example, the operations of method 1500 may be performed by a transmitter as described with reference to Figures 1 to 11 The transmitter described above. In some examples, the transmitter may execute an instruction set to control functional elements of the transmitter to perform the described functions. Additionally or alternatively, the transmitter may use dedicated hardware to perform aspects of the described functions.

[0199] At 1505, the method may include modulating one or more bits into a modulation sample sequence for wireless transmission to a receiver. The operations at 1505 may be performed according to the examples disclosed herein. In some examples, aspects of the operations at 1505 may be performed by the modulation component 1025 as described with reference to Figure 10 The modulation component 1025 described above.

[0200] At 1510, the method may include generating a first signal for transmission via a first transmit antenna from the modulation sample sequence and generating a second signal for transmission via a second transmit antenna from the modulation sample sequence according to a transmit interleaving pattern. The operations at 1510 may be performed according to the examples disclosed herein. In some examples, aspects of the operations at 1510 may be performed by the signal component as described with reference to Figure 10Performed by the described transmit interleaving component 1040.

[0201] At 1515, the method may include transmitting a first signal via a first transmit antenna and transmitting a second signal via a second transmit antenna, where the first signal and the second signal are transmitted via the first transmit antenna and the second transmit antenna, respectively, at non-overlapping times or via non-overlapping frequencies according to a transmit interleaving pattern. The operation of 1515 may be performed according to the examples disclosed herein. In some examples, aspects of the operation of 1515 may be performed by a signal component 1035 as described with reference to Figure 10 the described signal component 1035.

[0202] Figure 16 Illustrates a flowchart of a method 1600 that supports spatial diversity for low-power wake-up signals in accordance with one or more aspects of the present disclosure. The operations of method 1600 may be implemented by a transmitter or its components as described herein. For example, the operations of method 1600 may be performed by a transmitter as described with reference to Figures 1 to 11 the described transmitter. In some examples, the transmitter may execute an instruction set to control functional elements of the transmitter to perform the described functions. Additionally or alternatively, the transmitter may use dedicated hardware to perform aspects of the described functions.

[0203] At 1605, the method may include modulating one or more bits into a sequence of modulation samples for wireless transmission to a receiver. The operation of 1605 may be performed according to the examples disclosed herein. In some examples, aspects of the operation of 1605 may be performed by a modulation component 1025 as described with reference to Figure 10 the described modulation component 1025.

[0204] At 1610, the method may include generating a first signal for transmission via a first transmit antenna from the sequence of modulation samples and generating a second signal for transmission via a second transmit antenna from the sequence of modulation samples according to a transmit interleaving pattern. The operation of 1610 may be performed according to the examples disclosed herein. In some examples, aspects of the operation of 1610 may be performed by a transmit interleaving component 1040 as described with reference to Figure 10 the described transmit interleaving component 1040.

[0205] At 1615, the method may include transmitting the first signal as a first interleaving during a first portion of the on-duration of the sequence of modulation samples and transmitting the second signal as a second interleaving during a second portion of the on-duration of the sequence of modulation samples, where the first interleaving and the second interleaving are non-overlapping in time according to the transmit interleaving pattern. The operation of 1615 may be performed according to the examples disclosed herein. In some examples, aspects of the operation of 1615 may be performed by an interleaving component 1060 as described with reference to Figure 10 the described interleaving component 1060.

[0206] Figure 17 FIG. 1700 is a flow chart illustrating a method 1700 that supports spatial diversity for a low power wake signal in accordance with one or more aspects of the present disclosure. Operations of method 1700 may be implemented by a transmitter or components thereof as described herein. For example, operations of method 1700 may be performed by a transmitter as described with reference to Figures 1 to 11 described. In some examples, the transmitter may execute an instruction set to control functional elements of the transmitter to perform the described functions. Additionally or alternatively, the transmitter may use dedicated hardware to perform aspects of the described functions.

[0207] At 1705, the method may include modulating one or more bits into a sequence of modulation samples for wireless transmission to a receiver. The operation of 1705 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operation of 1705 may be performed by a modulation component 1025 as described with reference to Figure 10 described.

[0208] At 1710, the method may include generating a first signal for transmission via a first transmit antenna and a second signal for transmission via a second transmit antenna from the sequence of modulation samples according to a transmit interleaving pattern. The operation of 1710 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operation of 1710 may be performed by a transmit interleaving component 1040 as described with reference to Figure 10 described.

[0209] At 1720, the method may include transmitting the first signal via the first transmit antenna and the second signal via the second transmit antenna, where the first signal and the second signal are transmitted via the first transmit antenna and the second transmit antenna, respectively, at non-overlapping times or via non-overlapping frequencies according to a transmit interleaving pattern. The operation of 1720 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operation of 1720 may be performed by a signal component 1035 as described with reference to Figure 10 described.

[0210] An overview of aspects of the present disclosure is provided below:

[0211] Aspect 1: A method for wireless communication at a transmitter, the method comprising: modulating one or more bits into a sequence of modulation samples for wireless transmission to a receiver; applying a first phase cycling pattern to a plurality of subsequences of the sequence of modulation samples to generate a first phase-cycled modulation sample sequence for transmission via a first transmit antenna; applying a second phase cycling pattern to the plurality of subsequences of the sequence of modulation samples to generate a second phase-cycled modulation sample sequence for transmission via a second transmit antenna; transmitting a first signal via the first transmit antenna based at least in part on the first phase-cycled modulation sample sequence; and transmitting a second signal via the second transmit antenna based at least in part on the second phase-cycled modulation sample sequence.

[0212] Aspect 2: The method according to aspect 1, the method further comprising: multiplying a first subsequence of the plurality of subsequences by a first phase of the first phase cycling pattern for the first transmit antenna, and multiplying the first subsequence of the plurality of subsequences by a second phase of the second phase cycling pattern for the second transmit antenna, wherein the first phase is different from the second phase.

[0213] Aspect 3: The method according to any one of aspects 1 to 2, the method further comprising: applying the first phase cycling pattern to a first bit of the sequence of modulation samples and applying the second phase cycling pattern to the first bit of the sequence of modulation samples.

[0214] Aspect 4: The method according to any one of aspects 1 to 3, the method further comprising: converting the first phase-cycled modulation sample sequence into a first OFDM waveform and converting the second phase-cycled modulation sample sequence into a second OFDM waveform, wherein the first signal is generated based at least in part on the first OFDM waveform, and the second signal is generated based at least in part on the second OFDM waveform.

[0215] Aspect 5: The method according to aspect 4, wherein the first OFDM waveform and the second OFDM waveform are mapped to resources corresponding to a single OFDM symbol.

[0216] Aspect 6: The method according to any one of aspects 4 to 5, wherein the first OFDM waveform and the second OFDM waveform are mapped to resources corresponding to a plurality of OFDM symbols.

[0217] Aspect 7: The method according to any one of aspects 1 to 6, wherein the first signal and the second signal are associated with zero mean.

[0218] Aspect 8: The method according to any one of aspects 1 to 7, wherein the first phase-cycled modulation sample sequence and the second phase-cycled modulation sample sequence are each associated with zero mean.

[0219] Aspect 9: The method according to any one of aspects 1 to 8, wherein the first signal and the second signal include a low-power synchronization signal, a low-power preamble signal, a low-power wake-up signal, or any combination thereof.

[0220] Aspect 10: The method according to any one of aspects 1 to 9, wherein the modulated sample sequence includes an OOK sample sequence, an ASK sample sequence, or an FSK sample sequence.

[0221] Aspect 11: A method for wireless communication at a transmitter, the method comprising: modulating one or more bits into a modulated sample sequence for wireless transmission to a receiver; generating a first signal for transmission via a first transmit antenna and a second signal for transmission via a second transmit antenna from the modulated sample sequence according to a transmit interleaving pattern; and transmitting the first signal via the first transmit antenna and the second signal via the second transmit antenna, wherein the first signal and the second signal are transmitted via the first transmit antenna and the second transmit antenna, respectively, at non-overlapping times or via non-overlapping frequencies according to the transmit interleaving pattern.

[0222] Aspect 12: The method according to aspect 11, wherein the transmit interleaving pattern indicates interleaving the transmission of the first signal and the second signal across different frequency subbands of a resource allocation.

[0223] Aspect 13: The method according to any one of aspects 11 to 12, wherein transmitting the first signal and the second signal includes: transmitting the first signal during a first portion of the on-duration of the modulated sample sequence and transmitting the second signal during a second portion of the on-duration of the modulated sample sequence, wherein according to the transmit interleaving pattern, the first portion and the second portion of the on-duration occur at non-overlapping times.

[0224] Aspect 14: The method according to aspect 13, the method further comprising: a first transmit power level associated with the first signal during the first portion of the on-duration being equal to a second transmit power level associated with the second signal during the second portion of the on-duration.

[0225] Aspect 15: The method according to any one of aspects 11 to 14, wherein transmitting the first signal and the second signal comprises: transmitting the first signal as a first interleaving during a first portion of the on-duration of the modulated sample sequence and transmitting the second signal as a second interleaving during a second portion of the on-duration of the modulated sample sequence, wherein according to the transmission interleaving pattern, the first interleaving and the second interleaving are non-overlapping in time.

[0226] Aspect 16: The method according to any one of aspects 11 to 15, the method further comprising: transmitting the first signal via the first transmit antenna in a first sub-band of the allocated bandwidth and transmitting the second signal via the second transmit antenna using a second sub-band of the allocated bandwidth, wherein the first sub-band is different from the second sub-band.

[0227] Aspect 17: The method according to any one of aspects 11 to 16, wherein generating the first signal and the second signal comprises: generating the first signal and the second signal according to the transmission interleaving pattern indicating the application of a phase ramp in the frequency domain.

[0228] Aspect 18: The method according to any one of aspects 11 to 17, the method further comprising: converting a first interleaved modulated sample sequence into a first OFDM waveform and converting a second interleaved modulated sample sequence into a second OFDM waveform, wherein the first signal is generated at least in part based on the first OFDM waveform, and the second signal is generated at least in part based on the second OFDM waveform.

[0229] Aspect 19: The method according to aspect 18, wherein the first OFDM waveform and the second OFDM waveform are mapped to resources corresponding to a single OFDM symbol.

[0230] Aspect 20: The method according to any one of aspects 18 to 19, wherein the first OFDM waveform and the second OFDM waveform are mapped to resources corresponding to a plurality of OFDM symbols.

[0231] Aspect 21: The method according to any one of aspects 11 to 20, wherein the first signal and the second signal comprise a low-power synchronization signal, a low-power preamble signal, a low-power wake-up signal, or any combination thereof.

[0232] Aspect 22: The method according to any one of aspects 11 to 21, wherein the modulated sample sequence comprises an OOK sample sequence, an ASK sample sequence, or an FSK sample sequence.

[0233] Aspect 23: An apparatus for wireless communication at a transmitter, the apparatus comprising: a processor; a memory coupled to the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform the method according to any one of Aspects 1 to 10.

[0234] Aspect 24: An apparatus for wireless communication at a transmitter, the apparatus comprising at least one component for performing the method according to any one of Aspects 1 to 10.

[0235] Aspect 25: A non-transitory computer-readable medium storing code for wireless communication at a transmitter, the code comprising instructions executable by a processor to perform the method according to any one of Aspects 1 to 10.

[0236] Aspect 26: An apparatus for wireless communication at a transmitter, the apparatus comprising: a processor; a memory coupled to the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform the method according to any one of Aspects 11 to 22.

[0237] Aspect 27: An apparatus for wireless communication at a transmitter, the apparatus comprising at least one component for performing the method according to any one of Aspects 11 to 22.

[0238] Aspect 28: A non-transitory computer-readable medium storing code for wireless communication at a transmitter, the code comprising instructions executable by a processor to perform the method according to any one of Aspects 11 to 22.

[0239] It should be noted that the methods described herein describe possible specific implementations, and the operations and steps may be rearranged or otherwise modified and other specific implementations are also possible. In addition, aspects from two or more methods may be combined.

[0240] Although aspects of LTE, LTE-A, LTE-A Pro, or NR systems may be described for example purposes and the terms LTE, LTE-A, LTE-A Pro, or NR may be used in much of the description, the techniques described herein may also apply to networks other than LTE, LTE-A, LTE-A Pro, or NR networks. For example, the described techniques may apply to various other wireless communication systems such as Ultra Mobile Broadband (UMB), Institute of Electrical and Electronics Engineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDM, and other systems and radio technologies not explicitly mentioned herein.

[0241] The information and signals described herein may be represented using any of a variety of different technologies and methods. For example, data, instructions, commands, information, signals, bits, symbols, and chips referred to throughout the specification may be represented by voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, optical fields or optical particles, or any combination thereof.

[0242] The various illustrative blocks and components described in connection with the disclosure herein may be implemented or performed using a general purpose processor, DSP, ASIC, CPU, FPGA, or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. The general purpose processor may be a microprocessor, but in the alternative, the processor may be any processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration).

[0243] The functions described herein may be implemented using hardware, software executed by a processor, firmware, or any combination thereof. If implemented using software executed by a processor, the functions may be stored as one or more instructions or code on a computer-readable medium or transmitted using one or more instructions or code on a computer-readable medium. Other examples and implementations are within the scope of the present disclosure and the appended claims. For example, due to the nature of software, the functions described herein may be implemented using software executed by a processor, hardware, firmware, hardwiring, or any combination of these items. The features implementing the functions may also be physically located at different positions, including being distributed such that portions of the functions are implemented at different physical locations.

[0244] A computer-readable medium includes both a non-transitory computer storage medium and a communication medium, where the communication medium includes any medium that facilitates transfer of a computer program from one location to another. The non-transitory storage medium can be any available medium that can be accessed by a general or special purpose computer. By way of example, and not limitation, non-transitory computer-readable media can include RAM, ROM, electrically erasable programmable ROM (EEPROM), flash memory, compact disc read-only memory (CD-ROM) or other optical disc storage, magnetic disk storage or other magnetic storage devices, or any other non-transitory medium that can be used to carry or store desired program code components in the form of instructions or data structures and that can be accessed by a general or special purpose computer or a general or special purpose processor. Also, any connection is properly termed a computer-readable medium. For example, if software is transmitted using coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of computer-readable medium. As used herein, disk and disc include CD, laser disc, optical disc, digital versatile disc (DVD), floppy disk, and Blu-ray disc. A disk can magnetically reproduce data, and a disc can optically reproduce data using a laser. Combinations of the above are also included within the scope of computer-readable media.

[0245] As used herein (including in the claims), the "or" used in a list of items (e.g., a list of items accompanied by a phrase such as "at least one of" or "one or more of") indicates an inclusive listing such that, for example, the listing 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). Additionally, as used herein, the phrase "based on" should not be construed as a reference to a closed set of conditions. For example, an example step described as "based on condition A" can be based on both condition A and condition B without departing from the scope of the present disclosure. In other words, as used herein, the phrase "based on" should be interpreted in the same manner as the phrase "at least partially based on".

[0246] The term "determine" encompasses a variety of actions, and thus, "determine" can include operations, calculations, processing, derivation, research, lookups (such as looking up in a table, database, or other data structure), ascertaining, and similar actions. Additionally, "determine" can include receiving (e.g., receiving information), accessing (e.g., accessing data stored in a memory), etc. Further, "determine" can include parsing, obtaining, selecting, choosing, establishing, and other such similar actions.

[0247] In the accompanying drawings, like components or features may have the same reference numerals. Additionally, various components of the same type can be distinguished by adding a dash and a second numeral used to differentiate between like components after the reference numeral. If only the first reference numeral is used in the specification, the description can apply to any of the like components having the same first reference numeral, regardless of the second reference numeral or any other subsequent reference numerals.

[0248] The description set forth herein in connection with the accompanying drawings describes example configurations and does not represent all examples that may be implemented or that are within the scope of the claims. The term "example" as used herein means "serving as an example, instance, or illustration" and not "preferred" or "advantageous over other examples". The detailed description includes specific details for providing an understanding of the described techniques. However, the techniques may be practiced without these specific details. In some instances, well-known structures and devices are shown in block diagram form to avoid obscuring the concepts of the described examples.

[0249] The present description is provided to enable a person of ordinary skill in the art to make or use the present disclosure. Various modifications to the present disclosure will be readily apparent to those of ordinary skill in the art, and the general principles defined herein may be applied to other variations without departing from the scope of the present disclosure. Thus, the present disclosure is not limited to the examples and designs described herein and is to be accorded the broadest scope consistent with the principles and novel features disclosed herein.

Claims

1. An apparatus for wireless communication at a transmitter, the apparatus comprising: Processor; Memory coupled to the processor; And Instructions stored in the memory and executable by the processor to cause the device to: Modulate one or more bits into a sequence of modulation samples for wireless transmission to a receiver; Apply a first phase cycling pattern to a plurality of subsequences of the sequence of modulation samples to generate a first phase-cycled sequence of modulation samples for transmission via a first transmit antenna; Apply a second phase cycling pattern to the plurality of subsequences of the sequence of modulation samples to generate a second phase-cycled sequence of modulation samples for transmission via a second transmit antenna; Transmit a first signal via the first transmit antenna based at least in part on the first phase-cycled sequence of modulation samples; and Transmit a second signal via the second transmit antenna based at least in part on the second phase-cycled sequence of modulation samples.

2. The apparatus according to claim 1, wherein the instructions are further executable by the processor to cause the apparatus to: Multiply a first subsequence of the plurality of subsequences by a first phase of the first phase cycling pattern for the first transmit antenna and multiply the first subsequence of the plurality of subsequences by a second phase of the second phase cycling pattern for the second transmit antenna, wherein the first phase is different from the second phase.

3. The apparatus according to claim 1, wherein the instructions are further executable by the processor to cause the apparatus to: Apply the first phase cycling pattern to a first bit of the modulated sample sequence and apply the second phase cycling pattern to the first bit of the modulated sample sequence.

4. The apparatus according to claim 1, wherein the instructions are further executable by the processor to cause the apparatus to: Convert the first phase cycled modulated sample sequence into a first orthogonal frequency division multiplexing waveform and convert the second phase cycled modulated sample sequence into a second orthogonal frequency division multiplexing waveform, wherein the first signal is generated at least in part based on the first orthogonal frequency division multiplexing waveform, and the second signal is generated at least in part based on the second orthogonal frequency division multiplexing waveform.

5. The apparatus according to claim 4, wherein the first orthogonal frequency division multiplexing waveform and the second orthogonal frequency division multiplexing waveform are mapped to resources corresponding to a single orthogonal frequency division multiplexing symbol.

6. The apparatus according to claim 4, wherein the first orthogonal frequency division multiplexing waveform and the second orthogonal frequency division multiplexing waveform are mapped to resources corresponding to a plurality of orthogonal frequency division multiplexing symbols.

7. The apparatus according to claim 1, wherein the first signal and the second signal are associated with zero mean.

8. The apparatus according to claim 1, wherein the first phase cyclically modulated sample sequence and the second phase cyclically modulated sample sequence are each associated with zero mean.

9. The apparatus according to claim 1, wherein the first signal and the second signal include a low power synchronization signal, a low power preamble signal, a low power wake-up signal, or any combination thereof.

10. The apparatus according to claim 1, wherein the modulated sample sequence includes an on-off keying sample sequence, an amplitude shift keying sample sequence, or a frequency shift keying sample sequence.

11. An apparatus for wireless communication at a transmitter, the apparatus comprising: Processor; Memory coupled to the processor; And Instructions stored in the memory and executable by the processor to cause the device to: Modulate one or more bits into a sequence of modulation samples for wireless transmission to a receiver; Generate a first signal for transmission via a first transmit antenna and a second signal for transmission via a second transmit antenna from the sequence of modulation samples according to a transmission interleaving pattern; And Transmit the first signal via the first transmit antenna and the second signal via the second transmit antenna, wherein the first signal and the second signal are transmitted via the first transmit antenna and the second transmit antenna respectively at non-overlapping times or via non-overlapping frequencies according to the transmission interleaving pattern.

12. The apparatus according to claim 11, wherein the transmit interleaving pattern indicates interleaving the transmission of the first signal and the second signal across different frequency subbands of the resource allocation.

13. The apparatus according to claim 11, wherein the instructions for transmitting the first signal and the second signal are executable by the processor to cause the apparatus to: Transmit the first signal during a first portion of the on-duration of the modulated sample sequence and transmit the second signal during a second portion of the on-duration of the modulated sample sequence, wherein according to the transmit interleaving pattern, the first portion and the second portion of the on-duration occur at non-overlapping times.

14. The apparatus according to claim 13, wherein a first transmit power level associated with the first signal during the first portion of the on-duration is equal to a second transmit power level associated with the second signal during the second portion of the on-duration.

15. The apparatus according to claim 11, wherein the instructions are further executable by the processor to transmit the first signal and the second signal by being executable by the processor to perform the following operations: Transmit the first signal as a first interleaving during a first portion of the on-duration of the modulated sample sequence and transmit the second signal as a second interleaving during a second portion of the on-duration of the modulated sample sequence, wherein according to the transmission interleaving pattern, the first interleaving and the second interleaving are non-overlapping in time.

16. The apparatus according to claim 11, wherein the instructions are further executable by the processor to cause the apparatus to: Transmit the first signal via the first transmit antenna in a first sub-band of the allocated bandwidth and transmit the second signal via the second transmit antenna using a second sub-band of the allocated bandwidth, wherein the first sub-band is different from the second sub-band.

17. The apparatus according to claim 11, wherein the instructions are further executable by the processor to generate the first signal and the second signal by being executable by the processor to: Generate the first signal and the second signal according to the transmission interleaving pattern indicating the application of a phase ramp in the frequency domain.

18. The apparatus according to claim 11, wherein the instructions are further executable by the processor to cause the apparatus to: Convert a first interleaved modulation sample sequence into a first orthogonal frequency division multiplexing waveform and convert a second interleaved modulation sample sequence into a second orthogonal frequency division multiplexing waveform, wherein the first signal is generated at least in part based on the first orthogonal frequency division multiplexing waveform, and the second signal is generated at least in part based on the second orthogonal frequency division multiplexing waveform.

19. The apparatus according to claim 18, wherein the first orthogonal frequency division multiplexing waveform and the second orthogonal frequency division multiplexing waveform are mapped to resources corresponding to a single orthogonal frequency division multiplexing symbol.

20. The apparatus according to claim 18, wherein the first orthogonal frequency division multiplexing waveform and the second orthogonal frequency division multiplexing waveform are mapped to resources corresponding to a plurality of orthogonal frequency division multiplexing symbols.

21. The apparatus according to claim 11, wherein the first signal and the second signal include a low-power synchronization signal, a low-power preamble signal, a low-power wake-up signal, or any combination thereof.

22. The apparatus according to claim 11, wherein the modulated sample sequence includes an on-off keying sample sequence, an amplitude shift keying sample sequence, or a frequency shift keying sample sequence.

23. A method for wireless communication at a transmitter, the method comprising: Modulate one or more bits into a sequence of modulation samples for wireless transmission to a receiver; Apply a first phase cycling pattern to a plurality of subsequences of the sequence of modulation samples to generate a first phase-cycled sequence of modulation samples for transmission via a first transmit antenna; Apply a second phase cycling pattern to the plurality of subsequences of the sequence of modulation samples to generate a second phase-cycled sequence of modulation samples for transmission via a second transmit antenna; Transmit a first signal via the first transmit antenna based at least in part on the first phase-cycled sequence of modulation samples; and Transmit a second signal via the second transmit antenna based at least in part on the second phase-cycled sequence of modulation samples.

24. The method according to claim 23, the method further comprising: Multiply a first subsequence of the plurality of subsequences by a first phase of the first phase cycling pattern for the first transmit antenna and multiply the first subsequence of the plurality of subsequences by a second phase of the second phase cycling pattern for the second transmit antenna, wherein the first phase is different from the second phase.

25. The method according to claim 23, the method further comprising: Apply the first phase cycling pattern to the first bit of the sequence of modulation samples and apply the second phase cycling pattern to the first bit of the sequence of modulation samples.

26. The method according to claim 23, the method further comprising: Convert the first phase cyclic modulation sample sequence into a first orthogonal frequency division multiplexing waveform and convert the second phase cyclic modulation sample sequence into a second orthogonal frequency division multiplexing waveform, wherein the first signal is generated at least in part based on the first orthogonal frequency division multiplexing waveform, and the second signal is generated at least in part based on the second orthogonal frequency division multiplexing waveform.

27. A method for wireless communication at a transmitter, the method comprising: Modulate one or more bits into a modulation sample sequence for wireless transmission to a receiver; Generate a first signal for transmission via a first transmit antenna and a second signal for transmission via a second transmit antenna from the modulation sample sequence according to a transmission interleaving pattern; and Transmit the first signal via the first transmit antenna and transmit the second signal via the second transmit antenna, wherein the first signal and the second signal are transmitted via the first transmit antenna and the second transmit antenna respectively at non-overlapping times or via non-overlapping frequencies according to the transmission interleaving pattern.

28. The method according to claim 27, wherein the transmit interleaving pattern indicates transmitting the first signal and the second signal interleaved across different frequency subbands of a resource allocation.

29. The method according to claim 27, wherein transmitting the first signal and the second signal comprises: Transmit the first signal during a first portion of the on-duration of the modulation sample sequence and transmit the second signal during a second portion of the on-duration of the modulation sample sequence, wherein according to the transmission interleaving pattern, the first portion and the second portion of the on-duration occur at non-overlapping times.

30. The method according to claim 29, wherein a first transmit power level associated with the first signal during the first portion of the on - duration is equal to a second transmit power level associated with the second signal during the second portion of the on - duration.

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