Interference mitigation method for asynchronous time-division duplex

Abstract

Wireless communication systems and methods related to reducing UE (user equipment)-UE cross-link interference are provided. A UE (user equipment) can receive a TDD (time-division-duplexing) pattern from a BS (base station). The UE can set a guard band on uplink resources from resources specified in the TDD pattern. Alternatively, the UE can reduce the power for uplink resources from resources specified in the TDD pattern. The UE transmits resources using a carrier and as specified in the TDD pattern.

Description

Technology Field

[0001] This application claims priority and the benefit of U.S. Patent Application No. 17 / 115,779 filed on December 8, 2020 and U.S. Provisional Patent Application No. 62 / 947,963 filed on December 13, 2019, the entire contents of which are incorporated by reference.

[0002] The present application relates to wireless communication systems, and more specifically, to mitigating cross-link interference in asynchronous TDD (time division duplex) wireless communications. Background Technology

[0003] Wireless communication systems are widely deployed to provide various types of communication content, such as voice, video, packet data, messaging, and broadcast. These systems can support communication with multiple users by sharing available system resources (e.g., time, frequency, and power). A wireless multiple-access communication system may include multiple base stations (BSs) that each simultaneously support communication with multiple communication devices, which may be otherwise known as user equipment (UEs).

[0004] To meet the increasing demand for extended mobile broadband connectivity, wireless communication techniques are advancing from LTE (long-term evolution) techniques to next-generation NR (new radio) techniques, which can be referred to as 5G (5th Generation). For example, NR is designed to provide lower latency, higher bandwidth or higher throughput, and higher reliability than LTE. NR is designed to operate across a wide range of spectrum bands, such as low-frequency bands below approximately 1 GHz (gigahertz) and mid-frequency bands from approximately 1 GHz to approximately 6 GHz, as well as high-frequency bands like millimeter wave (mmWave) bands. NR is also designed to operate across different spectrum types, ranging from licensed spectrum to unlicensed and shared spectrum. Spectrum sharing enables operators to opportunistically aggregate spectrums to dynamically support high-bandwidth services. Spectrum sharing can extend the benefits of NR techniques to operational entities that do not have access to licensed spectrum.

[0005] UEs (115) associated with different networks, such as TDD networks, may experience cross-link interference. Cross-link interference can occur when UEs (115) are transmitting on adjacent carriers and using different TDD patterns. This causes different types of resources specific to TDD patterns to become misaligned and cause cross-link interference.

[0006] Some aspects of the present disclosure are summarized below to provide a basic understanding of the techniques discussed. This summary is not a comprehensive overview of all features considered in the present disclosure, nor is it intended to identify the core or important elements of all aspects of the present disclosure or to describe the scope of any or all aspects of the present disclosure. The sole purpose of this summary is to present some concepts of one or more aspects of the present disclosure in a summary form as an introduction to the more detailed descriptions to be presented later.

[0007] A method for avoiding cross-link interference in wireless communication comprises the steps of: receiving a second time-division-duplexing (TDD) pattern associated with a second UE from a base station (BS) by a first UE (user equipment) — the second TDD pattern specifies second resources on a carrier adjacent to the carrier of the first UE —; setting a guard band on the edge of a carrier containing at least one uplink resource when there is a resource type mismatch between at least one uplink resource from the first resources specified by the first TDD pattern associated with the first UE and at least one of the second resources by the first UE; and transmitting by the first UE to the BS the first resources including at least one uplink resource having a guard band on the edge of a carrier that carries at least one uplink resource on the carrier and as specified by the first TDD pattern.

[0008] The aspects further relate to setting a second guard band on a portion of a specific resource from first resources specified by a first TDD pattern by a first UE, wherein transmitting further includes transmitting a portion of the specific resource having the second guard band.

[0009] The aspects additionally relate to monitoring an indicator including a second TDD pattern used by a second UE to transmit second resources on a carrier adjacent to a carrier transmitting first resources in the first UE.

[0010] The aspects further relate to determining, in the first UE, that at least one uplink resource from the first resources specified in the first TDD pattern is aligned with at least one uplink resource from the second resources specified in the second TDD pattern, and transmitting at least one uplink resource without a guard band when alignment exists between at least one uplink resource specified in the first TDD pattern and at least one uplink resource specified in the second TDD pattern.

[0011] The aspects additionally relate to the first TDD pattern including locations of at least one uplink resource, at least one downlink resource, and at least one special resource in the first resources during a time period.

[0012] In an aspect of the present disclosure, user equipment (UE) comprises a transceiver; and a processor, wherein the transceiver is configured to receive a second time-division-duplexing (TDD) pattern associated with a second UE from a base station (BS) — the second TDD pattern specifies second resources on a carrier adjacent to the UE’s carrier — and to transmit to the BS first resources on the carrier and as specified in the first TDD pattern, the first resources including at least one uplink resource having a guard band on the edge of the UE’s carrier that carries at least one uplink resource, and the processor is configured to set a guard band on the edge of the carrier carrying at least one uplink resource when there is a resource type mismatch between at least one uplink resource from the first resources specified in the first TDD pattern associated with the UE and at least one of the second resources.

[0013] The aspects further relate to a processor being further configured to set a second guard band on a portion of a specific resource from first resources specified in a first TDD pattern, and a transceiver being further configured to transmit a portion of the specific resource having the second guard band in order to transmit the first resources.

[0014] The aspects further relate to the processor being additionally configured to monitor for an indicator comprising a second TDD pattern used by a second UE to transmit second resources on a carrier adjacent to the carrier transmitting first resources.

[0015] The aspects further relate to a processor determining that at least one uplink resource from first resources specified in a first TDD pattern is aligned with at least one uplink resource from second resources specified in a second TDD pattern, and, for transmitting the first resources, a transceiver further configured to transmit at least one uplink resource without a guard band when alignment exists between at least one uplink resource specified in a first TDD pattern and at least one uplink resource specified in a second TDD pattern.

[0016] Additionally, the aspects relate to the guard band reducing cross-link interference caused by resource type mismatch.

[0017] In an aspect of the present disclosure, a non-transient computer-readable storage medium on which program code is recorded, the program code comprises: a code for receiving a second time-division-duplexing (TDD) pattern associated with a second UE from a base station (BS) by a first UE (user equipment) — the second TDD pattern specifies second resources on a carrier adjacent to the carrier of the first UE — a code for setting a guard band on the edge of a carrier including at least one uplink resource when there is a resource type mismatch between at least one uplink resource from the first resources specified by the first TDD pattern associated with the first UE and at least one of the second resources by the first UE; and a code for transmitting by the first UE to the BS the first resources including at least one uplink resource having a guard band on the edge of the carrier that returns at least one uplink resource on the carrier and as specified by the first TDD pattern.

[0018] The aspects further relate to code for setting a second guard band on a portion of a specific resource from first resources specified by a first TDD pattern by a first UE, wherein the code for transmitting further includes code for transmitting a portion of the specific resource having the second guard band.

[0019] The aspects additionally relate to code for monitoring a second TDD pattern used by a second UE to transmit second resources on a carrier adjacent to a carrier transmitting first resources in a first UE.

[0020] The aspects further relate to code for determining, in a first UE, that at least one uplink resource from first resources specified in a first TDD pattern is aligned with at least one uplink resource from second resources specified in a second TDD pattern, and code for transmitting at least one uplink resource without a guard band when alignment exists between at least one uplink resource specified in a first TDD pattern and at least one uplink resource specified in a second TDD pattern.

[0021] The aspects additionally relate to the first TDD pattern including locations of at least one uplink resource, at least one downlink resource, and at least one special resource in the first resources during a time period.

[0022] In an aspect of the present disclosure, a UE (user equipment) comprises: means for receiving a second TDD (time-division-duplexing) pattern associated with a second UE from a BS (base station) — the second TDD pattern specifies second resources on a carrier adjacent to the UE’s carrier — means for setting a guard band on the edge of a carrier including at least one uplink resource when there is a resource type mismatch between at least one uplink resource and second resources from first resources specified by the first TDD pattern associated with the first UE by the first UE; and means for transmitting to the BS first resources including at least one uplink resource having a guard band on the edge of at least one uplink resource on the carrier and as specified by the first TDD pattern.

[0023] The aspects further relate to means for setting a second guard band on a portion of a specific resource from first resources specified in a first TDD pattern, wherein the means for transmitting further includes means for transmitting the portion of the specific resource having the second guard band.

[0024] The aspects relate to means for monitoring a second TDD pattern used by a second UE to transmit second resources on a carrier adjacent to a carrier transmitting first resources.

[0025] The aspects further relate to means for determining that at least one uplink resource from a first resource specified in a first TDD pattern is aligned with at least one uplink resource from a second resource specified in a second TDD pattern, and means for transmitting at least one uplink resource without a guard band when alignment exists between at least one uplink resource specified in the first TDD pattern and at least one uplink resource specified in the second TDD pattern.

[0026] Additionally, the aspects relate to the guard band reducing cross-link interference caused by resource type mismatch.

[0027] Other aspects, features, and embodiments of the present invention will become apparent to those skilled in the art upon reviewing the following description of specific exemplary embodiments of the present invention in conjunction with the accompanying drawings. While features of the present invention may be discussed with respect to the specific embodiments and drawings below, all embodiments of the present invention may include one or more of the advantageous features discussed herein. That is, while one or more embodiments may be discussed as having specific advantageous features, one or more of such features may also be used according to the various embodiments of the present invention discussed herein. In a similar manner, exemplary embodiments may be discussed below as device, system, or method embodiments, but it should be understood that such exemplary embodiments may be implemented in various devices, systems, and methods. Brief explanation of the drawing

[0028] FIG. 1 illustrates a wireless communication network according to some aspects of the present disclosure.

[0029] FIGS. 2a and 2b illustrate time division duplexing (TDD) patterns according to some aspects of the present disclosure.

[0030] FIG. 2c illustrates UE (user equipment)-UE (user equipment) cross-link interference according to some aspects of the present disclosure.

[0031] FIGS. 3a through 3c illustrate diagrams for reducing user equipment-user equipment cross-link interference according to some aspects of the present disclosure.

[0032] FIG. 4 is a block diagram of user equipment according to some aspects of the present disclosure.

[0033] FIG. 5 is a block diagram of a base station according to some aspects of the present disclosure.

[0034] FIG. 6 is a flowchart of a communication method according to some aspects of the present disclosure.

[0035] FIG. 7 is a flowchart of a communication method according to some aspects of the present disclosure. Specific details for implementing the invention

[0036] The detailed description below, in connection with the attached drawings, is intended to describe various configurations and is not intended to represent the only configurations in which the concepts described herein can be implemented. The detailed description includes specific details for the purpose of providing a complete understanding of the various concepts. However, it will be obvious to those skilled in the art that these concepts can be implemented without these specific details. In some cases, well-known structures and components are illustrated in the form of block diagrams to avoid obscuring such concepts.

[0037] The present disclosure relates to wireless communication systems, generally also referred to as wireless communication networks. In various embodiments, the technologies and devices may be used for wireless communication networks such as CDMA (code division multiple access) networks, TDMA (time division multiple access) networks, FDMA (frequency division multiple access) networks, OFDMA (orthogonal FDMA) networks, SC-FDMA (single-carrier FDMA) networks, LTE networks, GSM (Global System for Mobile Communications) networks, 5G (5th Generation) or NR (new radio) networks, as well as other communication networks. As described herein, the terms “networks” and “systems” may be used interchangeably.

[0038] OFDMA networks can implement radio techniques such as E-UTRA (evolved UTRA), IEEE (Institute of Electrical and Electronics Engineers) 802.11, IEEE 802.16, IEEE 802.20, and flash-OFDM. UTRA, E-UTRA, and GSM are part of the Universal Mobile Telecommunication System (UMTS). In particular, Long Term Evolution (LTE) is a release of UMTS that uses E-UTRA. UTRA, E-UTRA, GSM, UMTS, and LTE are described in literature provided by an organization named “3GPP (3rd Generation Partnership Project),” and cdma2000 is described in literature from an organization named “3GPP2 (3rd Generation Partnership Project 2).” These various radio techniques and standards are known or are under development. For example, the 3GPP (3rd Generation Partnership Project) is a collaboration among groups of telecommunications associations aimed at defining globally applicable 3G (third generation) mobile phone specifications. 3GPP LTE (long term evolution) is a 3GPP project aimed at improving UMTS mobile phone standards. 3GPP can define specifications for next-generation mobile networks, mobile systems, and mobile devices. The present disclosure relates to the advancement of radio techniques from LTE, 4G, 5G, NR, and beyond through shared access to the radio spectrum between networks using a new and different set of radio access techniques or radio air interfaces.

[0039] In particular, 5G networks consider various deployments, various spectrums, and various services and devices that can be implemented using OFDM-based integrated air interfaces. To achieve these goals, additional improvements to LTE and LTE-A are considered in addition to the development of new radio techniques for 5G NR networks. 5G NR is (1) ultra-high density (e.g., ~1M nodes / km 2 (2) for massive Internet of Things (IoTs) having deep coverage with the ability to reach difficult locations, ultra-low complexity (e.g., ~10s bits / sec), ultra-low energy (e.g., ~10+ years battery life); strong security to protect sensitive personal, financial, or confidential information, ultra-high reliability (e.g., ~99.9999% reliability), ultra-low latency (e.g., ~1ms); and mission-critical control for users with or without a wide range of mobility; and (3) extremely high capacity (e.g., ~10Tbps / km 2 It will be scalable to provide coverage with improved mobile broadband, including extreme data rates (e.g., multi-Gbps rates, 100+ Mbps user-experienced rates), and deep awareness with improved discovery and optimization.

[0040] 5G NR has a common flexible framework for efficiently multiplexing services and features using dynamic low-latency TDD (time division duplex) / FDD (frequency division duplex) designs; and can be implemented using optimized OFDM-based waveforms with scalable numerology and TTI (transmission time interval), featuring improved radio techniques such as massive MIMO (multiple input, multiple output), robust millimeter wave (mmWave) transmits, improved channel coding, and device-centric mobility. In 5G NR, the scalability of numerology, along with the expansion of the subcarrier spacing (SCS), can efficiently handle the operation of various services across various spectrums and various deployments. For example, in various outdoor and macro coverage deployments of FDD / TDD implementations below 3 GHz, the SCS can occur at 15 kHz across bandwidths (BW), such as 5, 10, or 20 MHz. For various other outdoor and small cell coverage deployments of TDD above 3 GHz, the SCS can occur at 30 kHz over an 80 / 100 MHz BW. For various other indoor broadband implementations, using TDD across the unlicensed portion of the 5 GHz band, the SCS can occur at 60 kHz over a 160 MHz BW. Finally, for various deployments transmitting using millimeter-wave components with 28 GHz TDD, the SCS can occur at 120 kHz over a 500 MHz BW.

[0041] The scalable numericality of 5G NR enables scalable TTI for various latency and quality of service (QoS) requirements. For example, shorter TTIs can be used for low latency and high reliability, while longer TTIs can be used for higher spectrum efficiency. Efficient multiplexing of long and short TTIs allows transmits to be initiated on symbol boundaries. 5G NR also considers an independent, integrated subframe design containing UL / downlink scheduling information, data, and acknowledgments within the same subframe. Independent, integrated subframes support communications in adaptive UP / downlink on unlicensed or contention-based shared spectrum that can be flexibly configured per cell to dynamically switch between the UL and downlink to satisfy current traffic demands.

[0042] Various other aspects and features of the present disclosure are further described below. It should be apparent that the teachings of this application may be embodied in a wide variety of forms, and that any particular structure, function, or both disclosed herein are merely illustrative and not limiting. Based on the teachings of this application, those skilled in the art should recognize that an aspect disclosed herein may be embodied independently of any other aspect, and that two or more of these aspects may be combined in various ways. For example, an apparatus may be embodied or a method may be practiced using any number of the aspects described herein. Furthermore, such an apparatus may be embodied or such a method may be practiced in addition to or using other structures, functions, or structures and functions in addition to one or more of the aspects described herein. For example, a method may be embodied as part of instructions stored on a computer-readable medium for execution on a system, device, apparatus, and / or processor or computer. Furthermore, an aspect may include at least one element of a claim.

[0043] This application describes mechanisms for identification.

[0044] Aspects of the present disclosure may provide several advantages.

[0045] FIG. 1 illustrates a wireless communication network (100) according to some aspects of the present disclosure. The network (100) may be a 5G network. The network (100) includes a plurality of base stations (BS) (105) (individually labeled as 105a, 105b, 105c, 105d, 105e, and 105f) and other network entities. A BS (105) may be a station communicating with UEs (115) and may also be referred to as an eNB (evolved node B), gNB (next generation eNB), access point, etc. Each BS (105) may provide communication coverage for a specific geographic area. In 3GPP, the term “cell” may refer to such a specific geographic coverage area of ​​a BS (105) and / or a BS subsystem serving that coverage area, depending on the context in which the term is used.

[0046] BS (105) can provide communication coverage for macro cells or small cells, such as pico cells or femto cells, and / or other types of cells. Generally, macro cells cover a relatively large geographical area (e.g., a radius of several kilometers) and may allow unrestricted access by UEs that have subscribed to the network provider. Small cells, such as pico cells, will generally cover a relatively smaller geographical area and may allow unrestricted access by UEs that have subscribed to the network provider. Small cells, such as femto cells, will also generally cover a relatively small geographical area (e.g., home) and, in addition to unrestricted access, may also provide restricted access by UEs that have an association with the femto cell (e.g., UEs in a closed subscriber group (CSG), UEs for users in the home, etc.). A BS for a macro cell may be referred to as a macro BS. A BS for a small cell may be referred to as a small cell BS, pico BS, femto BS, or home BS. In the example illustrated in FIG. 1, the BSs (105d and 105e) are general macro BSs, whereas the BSs (105a to 105c) may be macro BSs capable of 3D (3-dimensional), FD (full-dimensional), or massive MIMO. The BSs (105a to 105c) may utilize their higher-dimensional MIMO capabilities to employ 3D beamforming in both elevation and azimuth beamforming to increase coverage and capacity. The BS (105f) may be a small cell BS that may be a home node or a portable access point. The BS (105) may support one or more cells (e.g., two, three, four, etc.).

[0047] The network (100) may support synchronous or asynchronous operation. In the case of synchronous operation, the BSs may have similar frame timings, and transmissions from different BSs may be roughly aligned in time. In the case of asynchronous operation, the BSs may have different frame timings, and transmissions from different BSs may not be aligned in time.

[0048] UEs (115) are scattered throughout the wireless network (100), and each UE (115) may be stationary or mobile. A UE (115) may also be referred to as a terminal, mobile station, subscriber unit, station, etc. A UE (115) may be a cellular phone, PDA (personal digital assistant), wireless modem, wireless communication device, handheld device, tablet computer, laptop computer, cordless phone, WLL (wireless local loop) station, etc. In one aspect, a UE (115) may be a device including a UICC (Universal Integrated Circuit Card). In another aspect, a UE may be a device not including a UICC. In some aspects, UEs (115) not including UICCs may also be referred to as IoT devices or IoE (internet of everything) devices. UEs (115a to 115d) are examples of mobile smartphone-type devices accessing the network (100). The UE (115) may also be a machine specifically configured for connected communication, including machine type communication (MTC), enhanced MTC, narrowband IoT, etc. The UEs (115e to 115h) are examples of various machines configured for communication that access the network (100). The UEs (115i to 115k) are examples of vehicles equipped with wireless communication devices configured for communication that access the network (100). The UE (115) may be able to communicate with any type of BS, such as macro BS, small cell, etc., regardless of recognition.In FIG. 1, the lightning bolt symbol (e.g., communication links) indicates wireless transmissions between a serving BS (105) and a UE (115) that is a BS designated to serve the UE (115) on the DL (downlink) and / or UP (uplink), desired transmissions between BSs (105), backhaul transmissions between BSs, or sidelink transmissions between UEs (115).

[0049] During operation, BSs (105a to 105c) can serve UEs (115a and 115b) using 3D beamforming and coordinated spatial technologies, such as CoMP (coordinated multipoint) or multiple connections. The macro BS (105d) can perform backhaul communication with the BSs (105a to 105c) as well as with the small cell BS (105f). The macro BS (105d) can also transmit multicast services that UEs (115c and 115d) subscribe to and receive. Such multicast services may include mobile television or stream video, or other services for providing community information, such as weather advisories or alerts, such as Amber alerts or Grey alerts.

[0050] The BSs (105) may also communicate with the core network. The core network may provide user authentication, access authorization, tracking, IP (Internet Protocol) connectivity, and other access, routing, or mobility functions. At least some of the BSs (105) (e.g., gNB or ANC (access node controller)) may interface with the core network via backhaul links (e.g., NG-C, NG-U, etc.) and perform radio configuration and scheduling for communication with UEs (115). In various examples, the BSs (105) may communicate with each other directly or indirectly (e.g., via the core network) via backhaul links (e.g., X1, X2, etc.) which may be wired or wireless communication links.

[0051] The network (100) can also support mission-critical communications using highly reliable and redundant links to mission-critical devices, such as a UE (115e) which may be a drone. Redundant communication links with the UE (115e) may include links from macro BSs (105d and 105e) as well as links from small cell BSs (105f). Other machine-type devices, such as UE (115f) (e.g., thermometer), UE (115g) (e.g., smart meter), and UE (115h) (e.g., wearable device), can communicate in multi-stage-size configurations by communicating directly with BSs such as small cell BS (105f) and macro BS (105e) through the network (100), or with other user devices that relay their information to the network, such as UE (115f) communicating temperature measurement information to the smart meter UE (115g) (the information is subsequently reported to the network through the small cell BS (105f)). The network (100) may also provide additional network efficiency through dynamic low-latency TDD / FDD communications, such as V2V (vehicle-to-vehicle) communications between UEs (115i to 115k), V2X (vehicle-to-everying) communications between a UE (115i, 115j, or 115k) and other UEs (115), and / or V2I (vehicle-to-infrastructure) communications between a UE (115i, 115j, or 115k) and a BS (105). A network (100) providing TDD communications may be referred to as a TDD network.

[0052] In some implementations, the network (100) utilizes OFDM-based waveforms for communications. An OFDM-based system can divide the system BW into a number of (K) orthogonal subcarriers, which are also generally referred to as subcarriers, tones, bins, etc. Each subcarrier can be modulated with data. In some cases, the SCS between adjacent subcarriers can be fixed, and the total number of subcarriers (K) can be determined by the system BW. The system BW can also be divided into subbands. In other cases, the duration of the TTIs and / or the SCS can be scalable.

[0053] In some aspects, BSs (105) may allocate or schedule transmission resources (e.g., in the form of time-frequency resource blocks (RBs)) for DL ​​(downlink) and UL (uplink) transmissions in the network (100). DL refers to the transmission direction from the BS (105) to the UE (115), while UL refers to the transmission direction from the UE (115) to the BS (105). Communication may take place in the form of radio frames. A radio frame may be divided into multiple subframes or slots, for example, about 20. Each slot may be further divided into mini-slots. In FDD mode, simultaneous UL transmission and DL reception may occur in paired spectra. For example, each slot contains a UL subframe in the UL frequency band and a DL subframe in the DL frequency band. Subframes may also be referred to as slots. In TDD mode, UL transmission and DL reception occur in different time periods using the same frequency band (also referred to as unpaired spectrum). For example, a subset of slots in a radio frame (e.g., DL slots) may be used for DL ​​transmissions, and another subset of slots in a radio frame (e.g., UL slots) may be used for UL transmissions. In TDD mode, there are one or more slots containing periods that can be used to switch from resources used for DL ​​reception to resources used for UL transmission. Resources that can be used for switching from DL reception to UL transmission may be referred to as special or flexible resources.

[0054] DL slots and UL slots may be further subdivided into several zones. For example, each DL or UL slot may have pre-defined zones for transmitting reference signals, control information, and data. Reference signals are predetermined signals that enable communication between BSs (105) and UEs (115). For example, the reference signals may have a specific pilot pattern or structure, where the pilot tones may span an operating BW or frequency band, and each is positioned at a pre-defined time and a pre-defined frequency. For example, the BS (105) may transmit cell-specific reference signals (CRS) and / or channel state information-reference signals (CSI-RS) to enable the UE (115) to estimate the DL channel. Similarly, the UE (115) may transmit sounding reference signals (SRS) to enable the BS (105) to estimate the UL channel. Control information may include resource allocations and protocol controls. The data may include protocol data and / or operation data. In some aspects, the BSs (105) and UEs (115) may communicate using independent slots. An independent subframe may include a portion for DL ​​communication and a portion for UL communication. An independent slot may be DL-centric or UL-centric. A DL-centric subframe may include a longer duration for DL ​​communication than for UL communication. A UL-centric subframe may include a longer duration for UL communication than for DL ​​communication.

[0055] In some aspects, the network (100) may be an NR network deployed over licensed spectrum. BSs (105) may transmit synchronization signals (e.g., including a primary synchronization signal (PSS) and a secondary synchronization signal (SSS)) from the network (100) to enable synchronization. BSs (105) may broadcast system information associated with the network (100) (e.g., including a master information block (MIB), remaining system information (RMSI), and other system information (OSI)) to enable initial network access. In some cases, BSs (105) may broadcast the PSS, SSS, and / or MIB in the form of synchronization signal blocks (SSB) over a physical broadcast channel (PBCH), and broadcast the RMSI and / or OSI over a physical downlink shared channel (PDSCH).

[0056] In some aspects, a UE (115) attempting to access the network (100) can perform an initial cell search by detecting a PSS from the BS (105). The PSS can enable synchronization of period timing and may display a physical layer identity value. Then, the UE (115) can receive an SSS. The SSS can enable synchronization of radio frames and may provide a cell identity value, which may be combined with the physical layer identity value to identify the cell. The PSS and SSS may be located in the center of the carrier or at any suitable frequencies within the carrier.

[0057] After receiving the PSS and SSS, the UE (115) may receive an MIB that can be transmitted on the physical broadcast channel (PBCH). The MIB may contain system information for initial network access and scheduling information for the RMSI and / or OSI. After decoding the MIB, the UE (115) may receive the RMSI, OSI and / or one or more system information blocks (SIBs). The RMSI and / or OSI may contain RRC (radio resource control) information related to random access channel (RACH) procedures, paging, control resource set (CORESET) for monitoring physical downlink control channel (PDCCH), physical UL control channel (PUCCH), physical UL shared channel (PUSCH), power control, and SRS. In some aspects, SBI1 may contain cell access parameters and scheduling information for other SIBs.

[0058] After obtaining the MIB, RMSI, and / or OSI, the UE (115) may perform a random access procedure to establish a connection with the BS (105). In some examples, the random access procedure may be a four-step random access procedure. For instance, the UE (115) may transmit a random access preamble, and the BS (105) may respond with a random access response. The random access response (RAR) may include a detected random access preamble ID (identifier) ​​corresponding to the random access preamble, timing advance (TA) information, a UL grant, a temporary cell-radio network temporary identifier (C-RNTI), and / or a backoff indicator. Upon receiving the random access response, the UE (115) may transmit a connection request to the BS (105), and the BS (105) may respond with a connection response. The connection response may indicate a contention resolution. In some examples, the random access preamble, RAR, connection request, and connection response may be referred to as message 1 (MSG1), message 2 (MSG2), message 3 (MSG3), and message 4 (MSG4), respectively. In some examples, the random access procedure may be a two-stage random access procedure, wherein the UE (115) may transmit the random access preamble and connection request in a single transmission, and the BS (105) may respond by transmitting the random access response and connection response in a single transmission.

[0059] After establishing the connection, the UE (115) and the BS (105) can enter a normal operation stage, where operation data can be exchanged. For example, the BS (105) can schedule the UE (115) for UL and / or DL ​​communications. The BS (105) can transmit UL and / or DL ​​scheduling grants to the UE (115) via PDCCH. The scheduling grants can be transmitted in the form of DCI (DL control information). The BS (105) can transmit DL communication signals to the UE (115) via PDSCH according to the DL scheduling grants (e.g., return data). The UE (115) can transmit UL communication signals to the base station (105) via PUSCH and / or PUCCH according to the UL scheduling grants.

[0060] In some aspects, the BS (105) can improve communication reliability by using HARQ technologies to communicate with the UE (115), for example, by providing URLLC services. The BS (105) can schedule the UE (115) for PDSCH communication by sending a DL grant in the PDSCH. The BS (105) can send a DL data packet to the UE (115) according to the schedule in the PDSCH. The DL data packet can be sent in the form of a transport block (TB). If the UE (115) successfully receives the DL data packet, the UE (115) can send a HARQ ACK to the BS (105). Conversely, if the UE (115) does not successfully receive the DL transmission, the UE (115) can send a HARQ NACK to the BS (105). When the BS (105) receives a HARQ NACK from the UE (115), it may retransmit a DL data packet to the UE (115). The retransmission may contain a coded version of the DL data identical to the initial transmission. Alternatively, the retransmission may contain a coded version of the DL data different from the initial transmission. The UE (115) may apply soft-combination to combine the encoded data received from the initial transmission and the retransmission for decoding. The BS (105) and the UE (115) may also apply HARQ to UL communications using mechanisms substantially similar to DL HARQ.

[0061] In some aspects, the network (100) may operate through a system BW or a component carrier (CC) BW. The network (100) may divide the system BW into multiple BWPs (e.g., parts). The BS (105) may dynamically assign a UE (115) to operate through a specific BWP (e.g., a specific part of the system BW). The assigned BWP may be referred to as an active BWP. The UE (115) may monitor the active BWP for signaling information from the BS (105). The BS (105) may schedule the UE (115) for UL or DL ​​communications in the active BWP. In some aspects, the BS (105) may assign a pair of BWPs within the CC to the UE (115) for UL and DL communications. For example, a pair of BWPs may include one BWP for UL communications and one BWP for DL ​​communications.

[0062] In some aspects, the network (100) may operate over a shared channel that may include a shared spectrum or an unlicensed spectrum. For example, the network (100) may be an NR-U (NR-unlicensed) network operating over an unlicensed spectrum. In such aspects, the BSs (105) and UEs (115) may be operated by a number of network operating entities. To avoid collisions, the BSs (105) and UEs (115) may use a listen-before-talk (LBT) procedure to monitor transmission opportunities (TXOPs) on the shared channel. For example, a transmitting node (e.g., BS (105) or UE (115)) may perform an LBT before transmitting on the channel. When the LBT is passed, the transmitting node may proceed with transmission. When the LBT fails, the transmitting node may suppress transmission on the channel. In one example, the LBT may be based on energy detection. For example, LBT is passed when the signal energy measured from the channel is below a threshold. Conversely, LBT is failed when the signal energy measured from the channel exceeds the threshold. In another example, LBT can be based on signal detection. For example, LBT is passed when a channel reservation signal (e.g., a predetermined preamble signal) is not detected in the channel.

[0063] In some cases, in a network (100) that is a TDD network, UEs (115) may face UE-UE cross-link interference. This may occur when UEs (115) transmitting using adjacent carriers or the same carrier associated with different TDD networks are next to each other or within a certain distance of each other. When UE-UE interference occurs, the quality of service provided by the UEs (115) is reduced. The following aspects describe techniques for reducing UE-UE cross-link interference.

[0064] In some aspects, UEs (115) of a TDD network may transmit resources using TDD patterns. FIGS. 2a and 2b illustrate exemplary TDD patterns (200A and 200B) according to some aspects of the present disclosure. TDD patterns (200A and 200B) may be used by BSs such as BSs (105) and UEs (115) in a network such as network (100), which is a TDD network. In FIGS. 2a and 2b, the x-axis represents time in some arbitrary unit and the y-axis represents frequency in some arbitrary unit. TDD patterns (200A) may be transmitted using the same or different carriers.

[0065] The BSs (105) can configure the UEs (115) to have resources of the frequency band (202) during a time period (204). The time period (204) may refer to the cycle of TDD patterns (200A and 200B) specific to the TDD pattern. The resources include downlink (D) resources (206) used for downlink communication, uplink (U) resources (208) used for uplink communication, and special (S) resources (210) used for guard time between two D resources (206), two U resources (208), or D resources (206) and U resources (208). The S resources (210) may include an uplink portion and a downlink portion. The resources (206, 208, 210) are also known as slots.

[0066] In some aspects, TDD patterns such as TDD patterns (200A and 200B) are specified using a TDD configuration, which indicates a pool of resources (e.g., UL slots, DL slots, special S slots) in a frequency band (e.g., frequency band (202)) and time period (204) for each TDD pattern. In particular, the aspects described herein are not limited to TDD patterns (200A and 200B) and may be applicable to other TDD patterns. The TDD configuration may also specify the number of D resources (206), the number of U resources (208), and the number of S resources (210) within the time period (204) and frequency band (202).

[0067] In some aspects, TDD patterns, e.g., TDD patterns (200A and 200B), may be configured for different types of traffic. For example, TDD pattern (200A) may be configured for DL ​​heavy and latency-tolerant traffic, e.g., traffic associated with internet services. In another example, TDD pattern (200B) may be configured for UL heavy traffic and latency-sensitive traffic, e.g., traffic associated with industrial IoT (Internet-of-Things) traffic.

[0068] In some aspects, networks (100), which are TDD networks, can transmit TDD patterns, such as TDD patterns (200A and 200B), in an asynchronous manner leading to cross-link interference. Because the placement of different BSs (105) is static, cross-link interference caused by the BSs (105) of different TDD networks can be controlled to some extent by the operators and providers of the BSs (105). However, UEs (115) are mobile and move around the coverage areas covered by the BSs (105) in different TDD networks. Thus, UEs (115) associated with different TDD networks can operate at a distance from each other close enough to cause UE-UE cross-link interference.

[0069] UE-UE cross-link interference can occur when different UEs (115) transmit data using adjacent carriers that use different TDD patterns. Although UE-UE cross-link interference can occur in uplink and downlink transmissions, the embodiments below describe uplink UE-UE cross-link interference, but may be equally applicable to downlink interference. FIG. 2c is a block diagram illustrating UE-UE cross-link interference according to some aspects of the present disclosure. FIG. 2c illustrates two TDD patterns (200), namely, a TDD pattern (200A) that can be used by Carrier #1 and a TDD pattern (200B) that can be used by Carrier #2. Both TDD patterns (200A and 200B) have a time period (204). Carrier #1 and Carrier #2 may be adjacent carriers in the frequency spectrum.

[0070] In some cases, the first UE (115) from the first TDD network may use Carrier #1 to transmit resources as specified by the TDD pattern (200A), and the second UE (115) from the second TDD network may use Carrier #2 to transmit resources as specified by the TDD pattern (200B). The TDD pattern (200A) may be transmitted using a carrier during the frequency period (202A), and the TDD pattern (200B) may be transmitted using a carrier during the frequency period (202B).

[0071] In some cases, when there is a mismatch between the resource types of TDD patterns (200A and 200B) transmitted on adjacent carriers at the same time or during the same time period (204), cross-link interference(s) (212) may occur. The following aspects provide examples that may cause uplink cross-link interference (212). An example of cross-link interference (212A) may occur simultaneously when Carrier #1 returns a D resource (206) specific to the TDD pattern (200A) (i.e., the BS (105) of the TDD network for Carrier #1 transmits the D resource (206) and the UE (115) of the same TDD network for Carrier #1 receives the D resource (206)) and Carrier #2 returns a U resource (208) specific to the TDD pattern (200A) (i.e., the UE (115) of the TDD network for Carrier #2 transmits the U resource (208) and the BS (105) of the same TDD network for Carrier #2 receives the U resource (208). Another example of cross-link interference (212B) may occur when, simultaneously, Carrier #1 returns a D resource (206) specific to the TDD pattern (200A) and Carrier #2 returns an S resource (210) specific to the TDD pattern (200B). Another example of cross-link interference (212C) may occur when, simultaneously, Carrier #1 returns a U resource (208) specific to the TDD pattern (200A) and Carrier #2 returns a D resource (206) specific to the TDD pattern (200B). Another example of cross-link interference (212D) may occur when, simultaneously, the TDD pattern (200A) transmits a U resource (208) and the TDD pattern (200B) transmits an S resource (210).

[0072] The following aspects describe various techniques for avoiding or reducing the cross-link interference (212) discussed above. In one aspect, the BS (105) or UE (115) or other components of the TDD network may avoid or reduce cross-link interference by avoiding UL transmissions through a specific set of resource blocks (RBs) at the edges of carriers containing TDD patterns (200A and / or 200B). FIG. 3a is a block diagram including a guard band in a TDD pattern according to some aspects. As illustrated in FIG. 3a, the guard band (302) may be integrated into each U resource (208) included in the TDD pattern (200A) and each U resource (208) included in the TDD pattern (200B). The size of the guard band (302) may be configured by the UE (115) or BS (105). For example, a BS (105) or UE (115) may configure multiple RBs corresponding to the size of the guard band (302). Additionally, it is assumed that Carrier #1 uses a TDD pattern (200A) and Carrier #2 uses a TDD pattern (200B). The guard band (302) is contained in U resources (208) on adjacent edges of Carriers #1 and #2. This effectively creates a buffer between Carrier #1 and Carrier #2.

[0073] In some aspects, part of the S resource (210) associated with the uplink transmission may also include a guard band (302).

[0074] In some aspects, the guard band (302) may be integrated into the U resource (208) (and also the uplink portion of the S resource (210)) specified in the TDD pattern (200A, 200B) in various ways. In one aspect, the BS (105) or the UE (115) may configure the UL BWP (bandwidth part) to exclude a specific set of RBs on the edge of the carrier. In another example, the network (100) or the BS (105) may avoid scheduling or configuring UL transmissions that overlap with a specific set of RBs on the edge of the carrier. In another example, the UE (115) may drop all or part of the UL transmission when a UL transmission scheduled, indicated, or configured by the BS (105) overlaps with a specific set of RBs on the edge of the carrier.

[0075] In some aspects, networks (100) may use various techniques to determine when UL cross-link interference (212) may occur. In one aspect, TDD networks (100) may store individual TDD patterns (200) associated with TDD networks on a server accessible to multiple TDD networks. The stored information may also include frame timing information of the TDD carrier in the TDD network. Then, other networks (100) may access the server and obtain the TDD patterns (200). In this way, multiple networks (100) may share their individual TDD patterns (200).

[0076] In another aspect, networks (100) can use a backhaul to exchange TDD patterns (200) and time periods (204) of TDD patterns (200). The backhaul may be an alternative communication channel that networks (100) and / or components within networks (100) can use to share information, e.g., the Internet, 3G communication, etc.

[0077] In another aspect, one TDD network can monitor or listen to carriers of another TDD network. For example, when the TDD network does not have a signal or channel to transmit, the TDD network measures the strength of a signal received from a carrier available to the other TDD network. Then, the first TDD network (100) can identify TDD patterns used by the second TDD network, such as TDD pattern (200A), and then identify U resources (208) from the identified TDD pattern (200A). In some aspects, a BS (105) included in the first network (100) can listen to or monitor carriers of other TDD networks (100).

[0078] In another aspect, UEs (115) associated with the first TDD network may listen to or monitor interference caused by mismatched resources (206, 208, 210) on adjacent carriers used by the second TDD network. Listening to or monitoring such interference by the UEs (115) is possible when the UE has no transmission on its carrier. In this way, the first TDD network may be aware of the presence of adjacent carriers associated with the second TDD network. In one example, a UE (115) in the first TDD network may monitor the interference of adjacent carriers and estimate the TDD pattern (200) of the adjacent carriers used by the second TDD network, e.g., TDD patterns (200A, 200B). Then, the UEs (115) may report the estimated TDD pattern (200) to the BS (105) or another component of the first TDD network. In another example, UEs (115) may monitor interference of adjacent carriers and report interference variations to BS (105) and other components associated with the first TDD network for the analysis and identification of TDD patterns (200), e.g., TDD patterns (200A, 200B) associated with adjacent carriers in the second TDD network. The report may include one or more RSSI (received signal strength indicator), RSRP (reference signal received power), RSRQ (reference signal received quality), or SINR (signal-to-interference and noise ratio) values ​​over time, which are related to interference variations over time and provide information indicating resources colliding during downlink transmissions and resources colliding during uplink transmissions.

[0079] FIG. 3b is a block diagram including guard bands in a TDD pattern according to some aspects of the present disclosure. Similar to FIG. 3a, FIG. 3b illustrates guard bands (302) that are integrated into the uplink portions of each U resource (208) and S resource (210) included in the TDD patterns (200A and 200B). Unlike FIG. 3a, in FIG. 3b, guard bands (302) may be created when the TDD patterns (200A and 200B) of adjacent carriers #1 and #2 can cause UL cross-link interference (212). UL cross-link interference (212) may occur when there is a mismatch between the resource types of aligned resources transmitted on adjacent carriers #1 and #2, e.g., between a D resource (206) and a U resource (208) or between an S resource (210) and a U resource (208). FIG. 3b illustrates that no guard bands (302) are created on the edges of U resources (208) transmitted using aligned carriers #1 and #2. For example, it is assumed that carrier #1 uses a TDD pattern (200A) and carrier #2 uses a TDD pattern (200B), and that carriers #1 and #2 are adjacent. FIG. 3b illustrates two U resources (208) (illustrated as 304) specific to the aligned TDD patterns (200A, 200B). When the two UL resources (208) are aligned, there is no (or minimal) UL cross-link interference (212), and no guard bands (302) are included for the aligned UL resources (208).

[0080] In some aspects, UEs (115) and BSs (105) can determine whether potential UL cross-link interference (212) exists by using the timing and higher-level parameters of an adjacent carrier. Exemplary parameters may be TDD-UL-DL-ConfigCommon and TDD-UL-DL-ConfigDedicated provided by the radio resource configuration (RRC) parameter set. In one aspect, UEs (115) can obtain parameters by using RRC signaling (e.g., system information) in the received downlink data channel. In another aspect, UEs (115) can monitor the downlink data channel of an adjacent carrier (e.g., system information) and identify parameters using the system information. In yet another aspect, a DCI format, e.g., DCI format 2_0, can display TDD patterns (200) to the UE (115). DCI formats may be shared via backhaul signaling or identified using TDD pattern (200) detection by BSs (105) or UEs (115) as discussed above. In this way, UEs (115) associated with different TDD networks can determine the TDD patterns (200) of adjacent TDD networks. In some aspects, the UE (115) can know the TDD patterns (200) used by the adjacent TDD network by monitoring the carrier used by the UE (115) or the adjacent carrier used by the adjacent TDD network. For example, the UE (115) can know the TDD pattern (200) of the adjacent carrier by the DCI format 2_0 received by the UE (115) on its own carrier. In another example, the UE (115) can know the TDD pattern (200) of the adjacent carrier by monitoring the DCI format 2_0 of the adjacent carrier.

[0081] FIG. 3c is a block diagram illustrating a technique for reducing UL cross-link interference according to some aspects of the present disclosure. Unlike the aspects of FIG. 3a and FIG. 3b in which guard bands (302) are integrated into the edges of UL resources (208) on adjacent carriers #1 and #2, the aspects of FIG. 3c reduce the power for UL resources (208) on adjacent carriers. For example, a UE (115) can reduce the maximum transmit power used to transmit UL resources (208), which can reduce or eliminate UL cross-link interference. It is assumed that two UEs (115) associated with different TDD networks transmit on adjacent carriers #1 and #2, wherein carrier #1 uses TDD patterns (200A) and carrier #2 uses TDD patterns (200B). UEs (115) can transmit D resources (206) and S resources (210) (or downlink portion of S resources (210)) using maximum or full power, and then lower the power to transmit U resources (208).

[0082] In some aspects, the UE (115) may not reduce power to U resources (208) aligned with adjacent carriers (indicated by 304). As discussed above, aligned U resources (208) do not cause UL cross-link interference. In this case, the UE (115) may transmit U resources (208) of a TDD pattern (200A) aligned with U resources (208) of a TDD pattern (200B) using maximum or full power, and transmit U resources (208) of a TDD pattern (200A) not aligned with U resources (208) of a TDD pattern (200A) using reduced power.

[0083] A UE (115) associated with the first TDD network can determine or receive TDD patterns (200) of adjacent carriers used by the second TDD network, as discussed above.

[0084] In some aspects, the amount of power available to UEs (115) for transmitting U resources (208) can be configured by a configuration transmitted by the UE (115) or from the BS (105). For example, a TDD network may use a transmit power control (TPC) parameter indicating the power for transmitting U resources (208). Typically, the amount of power indicated by the TPC is less than the maximum power available to the UE (115) for transmitting resources. The BS (105) may transmit the TPC parameter to the UE (115) using a TPC command field in DCI format, e.g., DCI format 0_0, 0_1, 1_0, or 1_1, or DCI format 2_2. In other examples, the network (100) may configure upper-level parameters for the TPC. An exemplary upper-level parameter for the TPC may be PUSCH, e.g., P0_PUSCH. Then, BS (104) can transmit P0_PUSCH to UE (115). In some aspects, UE (115) can receive TPC parameters using, for example, DCI format or PUSCH, and transmit U resources (208) using the power indicated in the TPC parameters.

[0085] FIG. 4 is a block diagram of a UE (400) according to some aspects of the present disclosure. The UE (400) may be the UE (115) discussed above in FIG. 1. As illustrated, the UE (400) may include a processor (402), memory (404), a TDD module (408), a transceiver (410) including a modem subsystem (412) and a radio frequency (RF) unit (414), and one or more antennas (416). These elements may communicate with each other indirectly or directly, for example, through one or more buses.

[0086] The processor (402) may include a central processing unit (CPU), a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a controller, a field programmable gate array (FPGA) device, other hardware devices, a firmware device, or any combination of these configured to perform the operations described herein. The processor (402) may also be implemented as a combination of computing devices, for example, a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors combined with a DSP core, or any other such configuration.

[0087] Memory (404) may include cache memory (e.g., cache memory of the processor (402)), RAM (random access memory), MRAM (magnetoresistive RAM), ROM (read-only memory), PROM (programmable read-only memory), EPROM (erasable programmable read-only memory), EEPROM (electrically erasable programmable read-only memory), flash memory, solid-state memory devices, hard disk drives, other forms of volatile and non-volatile memory, or a combination of different types of memory. In one aspect, memory (404) includes a non-transient computer-readable medium. Memory (404) may store or have written instructions (406). Instructions (406) may include instructions that, when executed by the processor (402), cause the processor (402) to perform the operations described herein with reference to the UEs (115) in relation to aspects of the disclosure, e.g., aspects of FIGS. 6 and FIGS. 7. Instructions (406) may also be referred to as program code. Program code may be intended to cause the wireless communication device to perform such operations by, for example, causing one or more processors (e.g., processor (402)) to control or instruct the wireless communication device to perform the operations. The terms “instructions” and “code” should be broadly interpreted to include any type of computer-readable statement(s). For example, the terms “instructions” and “code” may refer to one or more programs, routines, sub-routines, functions, procedures, etc. “Instructions” and “code” may include a single computer-readable statement or many computer-readable statements.

[0088] The TDD module (408) can determine a TDD pattern that the UE (400) can use to transmit and receive information using Carrier #1 in a TDD network associated with the UE (400), and also a TDD pattern that the UE (115) in a different TDD network can use to transmit and receive information using Carrier #2, wherein Carrier #1 and Carrier #2 are adjacent carriers. Based on the determination, the TDD module (408) can cause the UE (400) to transmit information using a U resource including a guard band. In some cases, the TDD module (408) can be activated when the UE (115) from the different TDD network is within a configurable distance from the UE (400). Alternatively, the TDD module (408) can cause the UE (400) to transmit information using a U resource (208) using reduced power specified by TPC parameters.

[0089] The TDD module (408) may also use various techniques to identify TDD patterns used by adjacent carriers in different TDD networks. The TDD module (408) may obtain TDD patterns from the TDD network associated with the UE (400) or BS (105) or by monitoring adjacent carriers associated with different TDD networks for the TDD pattern. The TDD module (408) may be used for various aspects of the present disclosure, e.g., aspects of FIGS. 1 through 3, FIGS. 6, and FIGS. 7.

[0090] As illustrated, the transceiver (410) may include a modem subsystem (412) and an RF unit (414). The transceiver (410) may be configured to communicate bidirectionally with other devices, such as BSs (105). The modem subsystem (412) may be configured to modulate and / or encode data from memory (404). The RF unit (414) may be configured to process (e.g., perform analog-to-digital conversion or digital-to-analog conversion, etc.) modulated / encoded data (e.g., PSSCH data and / or PSCCH control information) of transmissions originating from the modem subsystem (412) or from other sources such as the UE (115) or BS (105) (for outbound transmissions). The RF unit (414) may be further configured to perform analog beamforming along with digital beamforming. Although shown as being integrated together in the transceiver (410), the modem subsystem (412) and RF unit (414) may be separate devices coupled together in the UE (115) to enable the UE (115) to communicate with other devices.

[0091] The RF unit (414) may provide modulated and / or processed data, such as data packets (or, more generally, data messages that may include one or more data packets and other information), to antennas (416) for transmission to one or more other devices. The antennas (416) may additionally receive data messages transmitted from other devices. The antennas (416) may provide the received data messages for processing and / or demodulation at the transceiver (410). The antennas (416) may include multiple antennas of similar or different designs to maintain multiple transmission links. The RF unit (414) may configure the antennas (416).

[0092] In some aspects, the transceiver (410) is configured to receive TDD patterns or TPC parameters from the BS (105) from another UE (115).

[0093] In some aspects, the UE (400) may include a plurality of transceivers (410) that implement different RATs (e.g., NR and LTE). In one aspect, the UE (400) may include a single transceiver (410) that implements a plurality of RATs (e.g., NR and LTE). In one aspect, the transceiver (410) may include various components, wherein different combinations of components may implement different RATs.

[0094] FIG. 5 is a block diagram of a BS (500) according to some aspects of the present disclosure. The BS (500) may be the BS (105) as described above in FIG. 1. As illustrated, the BS (500) may include a processor (502), memory (504), a TDD module (508), a transceiver (510) including a modem subsystem (512) and an RF unit (514), and one or more antennas (516). These elements may communicate with each other indirectly or directly, for example, through one or more buses.

[0095] The processor (502) may have various features as a specific-type processor. For example, it may include a CPU, DSP, ASIC, controller, FPGA device, other hardware device, firmware device, or any combination of these configured to perform the operations described herein. The processor (502) may also be implemented as a combination of computing devices, for example, a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors combined with a DSP core, or any other such configuration.

[0096] Memory (504) may include cache memory (e.g., cache memory of the processor (502)), RAM, MRAM, ROM, PROM, EPROM, EEPROM, flash memory, solid-state memory device, one or more hard disk drives, memristor-based arrays, other forms of volatile and non-volatile memory, or a combination of different types of memory. In some aspects, memory (504) may include a non-transient computer-readable medium. Memory (504) may store instructions (506). Instructions (506) may include instructions that, when executed by the processor (502), cause the processor (502) to perform the operations described herein, e.g., aspects of FIGS. 6 and FIGS. 7. Instructions (506) may also be referred to as code that can be broadly interpreted to include any type of computer-readable statement(s) as discussed above with respect to FIGS. 4.

[0097] The TDD module (508) may be implemented through hardware, software, or a combination thereof. The TDD module (508) may be implemented as instructions (506) stored in a processor, circuit, and / or memory (504) and executed by a processor (502). In some cases, the TDD module (508) may be integrated within a modem subsystem (512). The TDD module (508) may be implemented by a combination of software components (e.g., executed by a DSP or general processor) and hardware components (e.g., logic gates and circuits) within the modem subsystem (512).

[0098] The TDD module (508) may be used for various aspects of the present disclosure, e.g., aspects of FIGS. 1 through 3, FIG. 6, and FIG. 7. The TDD module (508) may be configured to transmit a TDD pattern that can be used by the UE (115, 400) to transmit resources and also to determine the TDD pattern of the UE (115) associated with a different TDD network transmitting resources on an adjacent carrier. The TDD module (508) may cause the BS (105) to transmit TDD patterns, such as the TDD pattern used by the TDD network associated with the UE (115) and the TDD pattern used by the UE (115) in a second TDD network. The TDD module (508) may format parameters that may include TDD patterns. The TDD module (508) can also transmit TPC parameters to the UE (115, 400) indicating the power that the UE (115) can use to transmit information using uplink resources to reduce uplink cross-link interference.

[0099] As illustrated, the transceiver (510) may include a modem subsystem (512) and an RF unit (514). The transceiver (510) may be configured to communicate bidirectionally with other devices, such as UEs (115 and / or 400) and / or other core network elements. The modem subsystem (512) may be configured to modulate and / or encode data according to an MCS, such as an LDPC coding scheme, a turbo coding scheme, a convolutional coding scheme, a digital beamforming scheme, etc. The RF unit (514) may be configured to process (e.g., perform analog-to-digital conversion or digital-to-analog conversion, etc.) the modulated / encoded data (e.g., grants, resource allocations) of transmissions originating from the modem subsystem (512) or from other sources such as the UE (115) or the UE (400) (for outbound transmissions). The RF unit (514) may be additionally configured to perform analog beamforming along with digital beamforming. Although shown as being integrated together in the transceiver (510), the modem subsystem (512) and / or RF unit (514) may be separate devices coupled together in the BS (105) to enable the BS (105) to communicate with other devices.

[0100] The RF unit (514) may provide the antennas (516) with modulated and / or processed data, such as data packets (or, more generally, data messages that may include one or more data packets and other information), for transmission to one or more other devices. This may include, for example, transmission of information to complete connection to a network according to some aspects of the present disclosure and communication with a camped UE (115 or 400). The antennas (516) may additionally receive data messages transmitted from other devices and provide the received data messages for processing and / or demodulation in a transceiver (510). The antennas (516) may include multiple antennas of similar or different designs to maintain multiple transmission links.

[0101] In one example, the transceiver (510) is configured to transmit a TDD configuration by cooperating with the TDD module (508). In one embodiment, the BS (500) may include a plurality of transceivers (510) that implement different RATs (e.g., NR and LTE). In one embodiment, the BS (500) may include a single transceiver (510) that implements a plurality of RATs (e.g., NR and LTE). In one embodiment, the transceiver (510) may include various components, wherein different combinations of components may implement different RATs.

[0102] FIG. 6 is a flowchart of a communication method (600) according to some aspects of the present disclosure. The steps of the method (600) may be executed by a wireless communication device or a computing device of other suitable means for performing the steps (e.g., a processor, a processing circuit, and / or other suitable components). For example, a wireless communication device such as UEs (115) or UE (400) may utilize one or more components, such as a processor (402), memory (404), TDD module (408), transceiver (410), modem (412), and one or more antennas (416) to execute the steps of the method (600). As illustrated, the method (600) includes a number of enumerated steps, but aspects of the method (600) may include additional steps before, after, and between the enumerated steps. In some aspects, one or more of the enumerated steps may be omitted or performed in a different order.

[0103] In step (610), the method (600) includes receiving a TDD pattern from a BS by the first UE. The TDD pattern (200) may be a pattern specifying resources for the second UE (115), such as D resources (206), U resources (208) and S resources (210), a time period (204), and a frequency band (202). The D resources (206) may transmit data and information from the BS (105) to the UE (115), the U resources (208) may transmit data and information from the UE (115) to the BS (105), and the S resources (210) may guard the time between the D resources (206) and the U resources (208). A carrier may be used to carry the resources (206, 208, 210) as a pattern included in the TDD pattern (200). The TDD pattern (200) received in step (610) may be a TDD pattern (200) associated with a second UE (115) transmitting on a carrier adjacent to the carrier used by the first UE (115).

[0104] In step (620), the method (600) includes setting a guard band by the first UE. The guard band (302) may include RBs at the edge of a carrier using the TDD pattern (200) of the first UE (115). Additionally, the guard band (302) may be included in U resources (208) specified by the TDD pattern (200) and the uplink portion of S resources (210). The first UE (115) or BS (105) may specify the size of the guard band (302) by configuring a plurality of RBs that may be included in the guard band (302). When the first UE (115) identifies a second UE (115) from a different TDD network transmitting on an adjacent carrier and uses the TDD pattern (200) received in step (610), the first UE (115) may set the guard band (302). The UE (115) can set the guard band (302) by excluding information about a portion of the U resource (208) covered by the guard band (302). When there is a resource type mismatch between aligned resources in the TDD patterns (200) of the first UE (115) and the second UE (115), the guard band (302) can reduce UL cross-link interference (212) between adjacent carriers. For example, when the first UE (115) identifies a U resource (208) of the TDD pattern (200) used by the first UE (115) that is aligned with a D resource (306) or an S resource (210) in the TDD pattern (200) used by the second UE (115), the first UE (115) can set the guard band (302). In some cases, the first UE (115) may not set a guard band (302) in the U resources (208). This may occur when the first UE (115) identifies a TDD pattern used by the second UE (115) and the U resources (208) specified by the TDD patterns (200) associated with the first and second UEs (115) are released.

[0105] In step (630), the method (600) includes transmitting resources to the BS (105) by the first UE using a pattern and carrier specified by the TDD pattern (200) associated with the first UE (115). The first UE (115) may transmit resources including U resources (208) and, in some cases, S resources (210) along with a guard band. In some cases, when there is a match between the U resources (208) of the TDD patterns (200) of the first UE (115) and the second UE (115), the first UE (115) may not include a guard band on the U resources (208).

[0106] FIG. 7 is a flowchart of a communication method (700) according to some aspects of the present disclosure. The steps of the method (700) may be executed by a wireless communication device or a computing device of other suitable means for performing the steps (e.g., a processor, a processing circuit, and / or other suitable components). For example, a wireless communication device such as UEs (115) or UE (400) may utilize one or more components, such as a processor (402), memory (404), TDD module (408), transceiver (410), modem (412), and one or more antennas (416) to execute the steps of the method (700). As illustrated, the method (700) includes a number of enumerated steps, but aspects of the method (700) may include additional steps before, after, and between the enumerated steps. In some aspects, one or more of the enumerated steps may be omitted or performed in a different order.

[0107] In step (710), the method (700) includes receiving a TDD pattern from a BS by the first UE. The TDD pattern (200) may be a pattern that specifies the resources of the second UE (115) that are transmitting on a carrier adjacent to the carrier of the first UE (115), such as D resources (206), U resources (208) and S resources (210), a time period (204), and a frequency band (202). The D resources (206) can transmit data and information from the BS (105) to the UE (115), the U resources (208) can transmit data and information from the UE (115) to the BS (105), and the S resources (210) can guard the time between the D resources (206) and the U resources (208). The carrier can be used to return resources (206, 208, 210) as a pattern included in the TDD pattern (200).

[0108] In step (720), the method (700) includes receiving a transmit power command (TPC) from the BS by the first UE. The TPC indicates the amount of power that the first UE (115) can use to transmit information using the U resource (208). The TPC command may be included in a TPC command field of DCI format 0_0, 0_1, 1_0 or 1_1 or DCI format 2_2. The TPC command may also be included in a higher-level parameter such as P0_PUSCH.

[0109] In step (730), the method (700) includes reducing power to uplink resources by the first UE. The location of the uplink resources (208) may be specified in the first UE's TDD pattern (200). When the first UE (115) identifies a second UE (115) from a different TDD network transmitting on an adjacent carrier and the TDD patterns (200) indicate that there is a mismatch in resource types, the first UE (115) may reduce power. For example, the first UE (115) may reduce power when there is an alignment between the first UE's (115) U resource (208) and the second UE's (115) D resource (206) or S resource (210). Power may be reduced from maximum or full power to power specified in the TPC. In some cases, when the first UE (115) identifies a TDD pattern used by the second UE (115) in a different TDD network and the U resources (208) of the TDD patterns associated with the first UE (115) and the second UE (115) are released, the first UE (115) may not reduce power.

[0110] In step (740), the method (700) includes transmitting resources to the BS (105) by the first UE using a carrier and as specified in the TDD pattern. The first UE (115) may transmit resources to the BS (105) using a carrier and as specified in the TDD pattern (200). Additionally, the U resources (208) may be transmitted using power specified in the TPC.

[0111] Information and signals may be represented using any of the various different techniques and technologies. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, optical fields or optical particles, or any combination thereof.

[0112] The various exemplary blocks and modules described herein in connection with the disclosure may be implemented or performed by general-purpose processors, DSPs, ASICs, FPGAs or other programmable logic devices, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general-purpose processor may be a microprocessor, but alternatively, the processor may be any conventional processor, controller, microcontroller, or state machine. Additionally, the processor may be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors combined with a DSP core, or any other such configuration).

[0113] The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. When implemented in software executed by a processor, the functions may be stored as one or more instructions or code on a computer-readable medium or transmitted therethrough. Other examples and implementations are within the scope of this disclosure and the appended claims. For example, due to the nature of the software, the functions described above may be implemented using software executed by a processor, hardware, firmware, hardwiring, or any combination thereof. Features implementing the functions may also be physically located in various positions, including distributed so that parts of the functions are implemented in different physical locations. Additionally, as used herein, including in the claims, “or” as used in a list of items (e.g., a list of items followed by phrases such as “at least one of” or “one or more of”) indicates a comprehensive list such that, for example, a list of [at least one of A, B, or C] means A or B or C or AB or AC or BC or ABC (i.e., A, B, and C).

[0114] As will now be recognized by those skilled in the art and depending on the specific application at hand, many modifications, substitutions, and changes may be made to and with respect to the materials, devices, configurations, and methods of use of the devices of this disclosure without departing from the spirit and scope of this disclosure. With this in mind, the scope of this disclosure should not be limited to the specific embodiments illustrated and described herein, as such embodiments are merely examples of this disclosure, but rather should fully correspond to the scope of the claims appended below and their functional equivalents.

Claims

Claim 1 A method for avoiding cross-link interference in wireless communication, comprising the steps of: receiving a second time-division-duplexing (TDD) pattern associated with a second UE from a base station (BS) by a first user device (UE) — said second TDD pattern specifies second resources on a carrier adjacent to the carrier of the first UE —; and, if there is a resource type mismatch between at least one uplink resource from the first resources specified in the first TDD pattern associated with the first UE and at least one second resource within the second resources, the first UE setting a guard band on the edge of the carrier including said at least one uplink resource — said guard band setting includes dropping all or part of the uplink transmission if the uplink transmission scheduled by the BS overlaps with said guard band —; A method for avoiding cross-link interference, comprising the step of transmitting the first resources, including the at least one uplink resource having the guard band on the edge of the carrier that returns the at least one uplink resource to the BS by the first UE, on the carrier and as specified in the first TDD pattern. Claim 2 A method for avoiding cross-link interference according to claim 1, wherein the method further comprises the step of setting a second guard band on a portion of a specific resource from the first resources specified in the first TDD pattern by the first UE; and the transmitting step further comprises the step of transmitting the portion of the specific resource having the second guard band. Claim 3 A method for avoiding cross-link interference according to claim 1, further comprising the step of monitoring, in the first UE, for an indicator including the second TDD pattern used by the second UE to transmit the second resources on a carrier adjacent to the carrier transmitting the first resources. Claim 4 A method for avoiding cross-link interference according to claim 1, wherein the setting step further comprises: determining that, in the first UE, at least one uplink resource from the first resources specified in the first TDD pattern is aligned with at least one uplink resource from the second resources specified in the second TDD pattern; and transmitting the at least one uplink resource without the guard band when alignment exists between the at least one uplink resource specified in the first TDD pattern and the at least one uplink resource specified in the second TDD pattern. Claim 5 A method for avoiding cross-link interference according to claim 1, wherein the first TDD pattern comprises the locations of at least one uplink resource, at least one downlink resource, and at least one special resource in the first resources during a time period. Claim 6 User equipment (UE) comprises a transceiver; and a processor, wherein the transceiver receives, from a base station (BS), a second time-division-duplexing (TDD) pattern associated with a second UE — said second TDD pattern identifies second resources on a carrier adjacent to the carrier of said UE —; A user device (UE) configured to transmit first resources, including at least one uplink resource having a guard band on the edge of the carrier of the UE that carries at least one uplink resource, on the carrier and as specified in the first TDD pattern, to the BS, and the processor configured to set the guard band on the edge of the carrier carrying the at least one uplink resource when there is a resource type mismatch between at least one uplink resource from the first resources specified in the first TDD pattern associated with the UE and at least one of the second resources, and setting the guard band includes dropping all or part of the uplink transmission when the uplink transmission scheduled by the BS overlaps with the guard band. Claim 7 In claim 6, the processor is further configured to set a second guard band on a portion of a specific resource from the first resources specified in the first TDD pattern; and to transmit the first resources, the transceiver is further configured to transmit the portion of the specific resource having the second guard band, user equipment (UE). Claim 8 In claim 6, the processor is further configured to monitor for an indicator comprising the second TDD pattern used by the second UE to transmit the second resources on a carrier adjacent to the carrier transmitting the first resources. Claim 9 In claim 6, the processor is further configured to determine that at least one uplink resource from the first resources specified in the first TDD pattern is aligned with at least one uplink resource from the second resources specified in the second TDD pattern; and to transmit the first resources, the transceiver is further configured to transmit the at least one uplink resource without the guard band when alignment exists between the at least one uplink resource specified in the first TDD pattern and the at least one uplink resource specified in the second TDD pattern, user equipment (UE). Claim 10 In claim 6, the guard band is a user device (UE) that reduces cross-link interference caused by the resource type mismatch. Claim 11 A non-transient computer-readable storage medium having program code written thereon, wherein the program code comprises: code for receiving a second time-division-duplexing (TDD) pattern associated with a second UE from a base station (BS) by a first user device (UE) — said second TDD pattern specifies second resources on a carrier adjacent to the carrier of the first UE —; code for setting a guard band on the edge of the carrier including the at least one uplink resource by the first UE, where there is a resource type mismatch between at least one uplink resource from the first resources specified in the first TDD pattern associated with the first UE and at least one resource within the second resources — said guard band setting includes dropping all or part of the uplink transmission scheduled by the BS if the uplink transmission overlaps with said guard band —; A non-transient computer-readable storage medium comprising a code for transmitting the first resources, including the at least one uplink resource having the guard band on the edge of the carrier that returns the at least one uplink resource to the BS by the first UE, on the carrier and as specified in the first TDD pattern. Claim 12 A non-transient computer-readable storage medium according to claim 11, further comprising code for setting a second guard band on a portion of a specific resource from the first resources specified in the first TDD pattern by the first UE, and the code for transmitting further comprising code for transmitting the portion of the specific resource having the second guard band. Claim 13 A non-transient computer-readable storage medium according to claim 11, further comprising code for monitoring an indicator including the second TDD pattern used by the second UE to transmit the second resources on a carrier adjacent to the carrier transmitting the first resources in the first UE. Claim 14 A non-transient computer-readable storage medium according to claim 11, further comprising: code for determining in the first UE that at least one uplink resource from the first resources specified in the first TDD pattern is aligned with at least one uplink resource from the second resources specified in the second TDD pattern; and code for transmitting the at least one uplink resource without the guard band when alignment exists between the at least one uplink resource specified in the first TDD pattern and the at least one uplink resource specified in the second TDD pattern. Claim 15 In claim 11, the first TDD pattern comprises the locations of at least one uplink resource, at least one downlink resource, and at least one special resource in the first resources during a time period, in a non-transient computer-readable storage medium. Claim 16 A user device (UE) comprising: means for receiving a second time-division-duplexing (TDD) pattern associated with the second UE from a base station (BS) — said second TDD pattern specifies second resources on a carrier adjacent to the carrier of the UE —; means for setting a guard band on the edge of the carrier including at least one uplink resource by the UE, where there is a resource type mismatch between at least one uplink resource from the first resources specified in the first TDD pattern associated with the UE and at least one resource within the second resources — said guard band setting includes dropping all or part of the uplink transmission when the uplink transmission scheduled by the BS overlaps with said guard band —; and means for transmitting the first resources including the at least one uplink resource having said guard band on the edge of the at least one uplink resource on the carrier and to the BS as specified in the first TDD pattern. Claim 17 In claim 16, the user equipment (UE) further comprises means for setting a second guard band on a portion of a specific resource from the first resources specified in the first TDD pattern; and means for transmitting further comprises means for transmitting the portion of the specific resource having the second guard band. Claim 18 In claim 16, the user equipment (UE) further comprises means for monitoring the second TDD pattern used by the second UE to transmit the second resources on a carrier adjacent to the carrier transmitting the first resources. Claim 19 In claim 16, the user equipment (UE) further comprises: means for determining that at least one uplink resource from the first resources specified in the first TDD pattern is aligned with at least one uplink resource from the second resources specified in the second TDD pattern; and means for transmitting the at least one uplink resource without the guard band when alignment exists between the at least one uplink resource specified in the first TDD pattern and the at least one uplink resource specified in the second TDD pattern. Claim 20 In claim 16, the guard band is a user device (UE) that reduces cross-link interference caused by the resource type mismatch.

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