Patent Description:
Examples of such multiple-access technologies include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, orthogonal frequency division multiple access (OFDMA) systems, and single-carrier frequency division multiple access (SC-FDMA) systems.

<NPL>, relates to a discussion and proposals on M-PDCCH common search space design.

<NPL>, relates to a discussion and proposals on CSS for paging USS and identifies what are configured as cell-specific and what are configured as UE-specific.

For example, <NUM> new radio (NR) communications technology is envisaged to expand and support diverse usage scenarios and applications with respect to current mobile network generations. In an aspect, <NUM> communications technology includes enhanced mobile broadband addressing human-centric use cases for access to multimedia content, services and data; ultra-reliable-low latency communications (URLLC) with strict requirements, especially in terms of latency and reliability; and massive machine type communications for a very large number of connected devices and typically transmitting a relatively low volume of non-delay-sensitive information. As the demand for mobile broadband access continues to increase, however, there exists a need for further improvements in <NUM> communications technology and beyond.

It is envisaged that <NUM> NR will provide more flexibility in wireless communications. This increased flexibility can apply to different aspects of wireless communications, including the various mechanisms and techniques used for scheduling or conveying (e.g., signaling) information about assignments and/or availability of communications resources. Accordingly, there is a need for new techniques in the implementation and design of PDCCH that would enable and support the improvements in wireless communications flexibility provided by <NUM> NR.

The invention provides for new implementations and designs related to various aspects PDCCH as used in <NUM> NR wireless communications.

Various aspects regarding the design or implementation of PDCCH in <NUM> NR are described below. For example, additional details regarding the design or implementation of multiple PDCCH search spaces, the concept of control resource block (CRB), the design or implementation of irregular multiple slots or mini slots grant, and the use of a fast control signaling for grant-free uplink (UL), are provided below. For example, different scheduling entities can each have one or two search spaces defined (e.g., common and/or user equipment (UE)-centric search spaces). Also, CRBs can be used as units for PDCCH transmission instead of resource element groups/control channel elements (REGs/CCEs). In addition, irregularities in time domain, frequency domain, or both can be introduced in the granting of resource blocks (RBs) over multiple slots or mini-slots. Moreover, signaling can be used to indicate to a UE configured for grant-free UL the portion of the pool of resources available for grant-free UL.

In a typical scenario, a UE does not attempt to decode every PDCCH. To impose as few restrictions as possible on the scheduler while at the same time limit the maximum number of blind decoding attempts in the terminal, LTE or legacy wireless technologies define so-called search spaces, which describe the set of CCEs the terminal (e.g., the UE) is supposed to monitor for scheduling assignments/grants relating to a certain component carrier. A search space is a set of candidate control channels formed by CCEs on a given aggregation level, which the terminal is supposed to attempt to decode.

In legacy networks (e.g., LTE networks) there are two types of search spaces used in PDCCH or ePDCCH to control each carrier: common search spaces and UE-specific search spaces. A common search space is shared across all UEs and a UE-specific search space is used on a per UE basis (e.g., there is a search space specific for each UE). UEs decode the PDCCH within <NUM> UE-specific search spaces and <NUM> common search spaces. For each carrier, there is a definition of a resource element group (REG) and on top of that there are control channel elements (CCEs). The PDCCH candidates are transmitted using a number of the CCEs. Nine sets of four physical resource elements (REs) known as the REGs make up each CCE. Thus, one CCE can include <NUM> REs. The number of CCEs used for a PDCCH may be <NUM>, <NUM>, <NUM>, or <NUM>. Each search space comprises a group of consecutive CCEs which could be allocated to a PDCCH called a PDCCH candidate. Thus, the search space in legacy networks uses CCE as a basic unit for control. Different search spaces will have CCE locations within the CCE space. A UE will decode all decoding candidates (e.g., all the hypotheses) in these two search spaces to discover that UE's downlink control information (DCIs). DCI signals (e.g., conveys information regarding scheduling assignments) the allocation of resources to the UE. For example, the UE may use the DCI to schedule UL resources on the PUSCH and DL resources on the PDSCH. There may be different DCI formats, where DCI format <NUM> is typically used for the allocation of uplink resources while the other formats are typically used for the allocation of downlink resources. The allocation of resources happens in terms of CCEs. The common search space and the UE-specific search space for different UEs are multiplexed at the CCE level. Moreover, across different eNBs (e.g., network entities with different physical cell identifiers or PCIs), the CCE (REG) space is randomized.

In <NUM> NR applications, however, the DCI may come from different entities, which may be referred to as network entities, transmit or transmission entities, or scheduling entities. For example, the DCI may come from an eNB, from a zone (e.g., for uplink (UL) mobility), or from a Coordinated Multi-Point (CoMP) cooperation set (CCS), or from other types of scheduling entities. A UE, therefore, may be served by more than one scheduling entity. In the past, the UE may have monitored multiple eNBs, but now it may need to monitor different types of scheduling entities. For example, for a carrier a UE may need to monitor two or more of an eNB, a cell, a zone, or a CCS. That is, in legacy networks, a UE may monitor entities of the same type, while for <NUM> NR a UE may monitor multiple entities of different types.

An approach to address this difference between <NUM> NR networks and legacy networks is to define different search spaces for different scheduling entities (see e.g., <FIG>). For example, a different or unique search space can be defined for each network entity. As described above, the scheduling entities supported in <NUM> NR networks for which unique search spaces can be defined may include an eNB, a transmit/receive point (TRP), a zone (e.g., for UL mobility), a CCS, and others. This is in contrast with legacy networks that only support search spaces for eNBs and where the common search space is shared for all UEs. A common search space and a UE-specific search space may be defined for each scheduling entity. In some instances, however, only one or the other search space may need to be defined. For example, while for an eNB as a scheduling entity both a common search space and a UE-specific search space may be defined, for a CCS as a scheduling entity it may be sufficient to define UE-specific search space, while for a zone as a scheduling entity it may be sufficient to define a common search space (see e.g., <FIG>). The UE is pre-configured with information about each of the search spaces so that the UE can monitor the search spaces. For example, the UE may be aware of different search space information such as, but not limited to, the DCI format/sizes, the Radio Network Temporary Identifier (RNTI) (e.g., for decoding), the cell identifier (ID) (or other type of identifier), the set of slots to monitor, the number of decoding candidates, and/or other aspects that may be separately managed for each search space.

In each search space that a UE can monitor there may be aggregation levels (see e.g., <FIG>). Within each of the search spaces, the aggregation levels may be nested. The number of CCEs used for a PDCCH is also referred to as the aggregation level. For example, if aggregation level is <NUM>, a single CCE may be used for the PDCCH. If the aggregation level is <NUM>, two CCEs may be used for the PDCCH. Similarly for aggregation levels <NUM>, <NUM>, and <NUM>, for example as shown in <FIG>. Regarding the nesting, if the aggregation level is <NUM> and CCEs #<NUM> and #<NUM> are being used, it is possible to nest smaller aggregation levels, such as an aggregation level <NUM> for CCE #<NUM> and an aggregation level <NUM> for CCE #<NUM>. The number of CCEs aggregated for transmission of a particular PDCCH may be determined according to the channel conditions. For example, under good downlink channel conditions, one CCE is likely to be sufficient. However, when a PDCCH is intended for a UE under poor channel conditions (e.g., near the cell border) then a larger number of CCEs may be used (e.g., <NUM> CCEs or <NUM> CCEs).

In a first alternative of how to manage the search space location, each search space can have its own REG/CCE space (see e.g., <FIG>). That is, each scheduling entity may be treated like different eNBs were treated in legacy networks (e.g., LTE networks/systems). Therefore, the location of the REG/CCE depends on the identity of the entity. In legacy networks the identity could be based on PCI, for example). If this approach were applied to <NUM> NR networks, each search space can be effectively treated as if it were from a different PCI in a legacy network. The issue that may arise in this alternative is that the REG/CCE from different search spaces may conflict or overlap. That is, the CCEs may not be aligned, which may cause collisions. For example, if CCE #<NUM> from a first scheduling entity overlaps with CCEs #<NUM> and #<NUM> of a second scheduling entity, then when using CCE #<NUM> of the first scheduling entity CCEs #<NUM> and #<NUM> of the second scheduling entity may not be used.

According to the invention resulting in fewer conflicts or collisions and may therefore be suitable for the conditions found in <NUM> NR networks, the same REG/CCE space is shared across all search spaces but each search space hashes to a different range of CCEs in the same CCE space (see e.g., <FIG>). In other words, the REG/CCEs for each scheduling entity may be uniquely defined to avoid conflicts providing search space coordination among the different scheduling entities. In contrast to the first alternative described above, in which the scheduling entities may not be coordinated as in legacy networks, this second alternative allows for the scheduling entities to be coordinated to avoid conflicts or collisions and such coordination can take place in different layers (e.g., with some level of hierarchy involved). Each of the alternatives described above can be similarly implemented with the use of CRBs, which is described in more detail below.

In another aspect, the present disclosure proposes the use of control resource blocks (RBs) in <NUM> NR networks as a unit for PDCCH. In legacy networks such as LTE, PDCCH is based on units of REGs (e.g., data REs), then CCE (e.g., group of REGs), then DCI with Cell-Specific Reference Signal (CRS) as phase reference for decoding. The CRS is not precoded and is also generally assumed from the same antenna port, which allows a UE to use wideband channel estimation for the PDCCH decoding. The CRS is distributed in frequency within the control symbol.

In <NUM> NR applications it may be desirable to use beamforming/precoding in connection with PDCCH. For <NUM> NR networks, because of the use of massive multiple-input-multiple-output (MIMO), millimeter wave (mmWave), and other transmission techniques, the PDCCH may need to be precoded as well for coverage. That is, if beamforming is being applied to data but not to control information, it may be the case that the data is able to reach a UE but not the control information. As such, precoding of both control and data may be desirable in <NUM> NR applications.

One solution being proposed in this disclosure is to introduce CRBs for PDCCH. In <NUM> NR, instead of using the REG concept, the CRB can be defined as a new unit for PDCCH, providing a self-contained structure for control. For example, each CRB may be a continuous set of tones in PDCCH (e.g., <NUM> or <NUM> continuous tones over <NUM> or <NUM> control orthogonal frequency-division multiple (OFDM) symbols). Examples of CRBs having <NUM> OFDM symbols are illustrated in <FIG>. For reasonable channel estimation quality, the size of the CRB may not be too small.

The CRB may be configured to contain or include the reference signal (RS) resource (also referred to as control RS resources). The RS resources can be included in the first of two OFDM symbols.

Within each CRB, the RS and the data resource elements (REs) may be precoded in the same fashion. That is, both the RS and the data REs may be similarly precoded. A special case may be when both the RS and the data REs are not precoded.

As noted above, the CRB may be used to replace the REG concept used in legacy networks, and the CCE may instead be formed by multiple CRBs (e.g., <NUM> or <NUM> CRBs). The CRB may therefore be larger than an REG.

There may be different ways to perform the beamforming/precoding across CRBs. For example, in a first alternative, across a set of CRBs, the same beamforming may be used to support wide band channel estimation. This approach may be useful for common PDCCH regions where the RS may be used for tracking and burst detection. The UE is aware or preconfigured with this information to perform the decoding, that is, the UE is configured to perform wideband channel estimation across the CRBs and decode the PDCCH. The UE may be made aware by information included in the CRBs or by some form of RRC configuration. A special case of having the same beamforming across RBs can be not to apply any beamforming at all and simply use an omnidirectional pattern.

In a second alternative, the CRBs may be independently decoded. This type of precoding approach may be configured to adapt to channel variations better. This approach may be a better fit for the case where the CRBs are distributed in frequency. In this approach, the UE may perform a per CRB channel estimation.

The CRBs may be localized and distributed. For example, the concept of the CRB may also include the concepts of virtual CRB and physical CRB. For localized CRB, virtual CRBs may be mapped to continuous physical CRBs for sub-band scheduling gain. For distributed CRBs, virtual CRBs may be mapped to distributed physical CRBs to collect more diversity. For localized CRBs, there need not be any interleaving because a linear mapping is applied. For distributed CRBs, however, interleaving may be used to separate the CRBs and provide diversity.

The CRB concept described above may also be applied to dual-stage PDCCH (or more generally to multi-stage PDCCH). For example, the CRB concept may apply to dual-stage PDCCH when the CRB contains one or more OFDM symbols and the RS may be front loaded (e.g., RS are located in the first OFDM symbol).

In dual-stage PDCCH or dual-stage DCI, the approach is to split the DCI into two parts to have better scheduling flexibility, processing timeline and/or less overhead. The first part of the DCI in the first OFDM symbol may include information that may not depend on the previous physical uplink control channel (PUCCH) feedback, and may be relevant for the early preparation of reception/transmission (RX/TX) later. The second part of the DCI may include information that may depend on the previous PUCCH feedback (e.g., longer timeline to process PUCCH).

When applying CRB to dual-stage PDCCH, the CRB may be assigned to the same UE. In this case, the data REs in the first OFDM symbol may be used for the first part of the DCI, and the data REs in the second OFDM symbol may be used for the second part of the DCI. That is, the first stage of the dual-stage PDCCH is in the first OFDM symbol and the second stage of the dual-stage PDCCH is in the second symbol. The RS may be shared between the two parts, which may be an efficient approach in the case that the RS is precoded.

In another aspect regarding the design or implementation of PDCCH for <NUM> NR, wireless transmissions in <NUM> NR may be in units of slots or mini-slots. A mini-slot may be the smallest possible scheduling unit and may be smaller than a slot or a subframe. In one approach, when multiple slots or mini-slots are used, the same set of resource blocks (RBs) may be granted to the UE in a continuous set of slots or mini slots.

To obtain higher flexibility in the time domain, however, a more irregular granting of resources may be desirable. For example, in a first alternative, the same RBs are used across a selected set of (mini-)slots. This can be similar to multi-(mini-)slot grant design but in the case for <NUM> NR time domain irregularity is introduced. The benefit of such an approach may include leaving some space for other traffic (e.g., ultra-reliable-low latency communications (URLLC)), create allocation pattern that fits some traffic pattern, or both. In this approach, a bitmap may be used to indicate the set of (mini-)slots covered in the grant. Moreover, it is possible to define several time domain patterns to save bits if the full flexibility is not needed.

For example, if the slots (or mini-slots) granted are <NUM>, <NUM>, <NUM>, and <NUM> (with slot <NUM> not granted), a bitmap such as (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) may be created to indicate the pattern of the resources being granted to slots <NUM>, <NUM>, <NUM>, and <NUM>. The price or cost of this approach is to include the bitmap in the control message adding to the payload for the PDCCH.

In another example, a set of predefined patterns may be used (e.g., <NUM>. , or <NUM>. ), where each pattern is then indicated by an index value in the PDCCH. This approach may require less overhead but also provides less flexibility.

In a second alternative, arbitrary RBs may be used over all slots or mini-slots (e.g., using a longer bitmap). In an aspect, sequentially numbered RBs (or RBGs) may be used in multiple (mini-)slots. For example, if RBs are granted into multiple mini-slots, and the first mini-slot has <NUM> RBs and the second mini-slot has <NUM> RBs, then the RBs in the first mini-slot are numbered <NUM>-<NUM> and the RBs in the second mini-slot are numbered <NUM>-<NUM>. There may be different RB patterns within each min-slot. Moreover, the resource allocation (RA) in the DCI may work on the concatenated RB/resource block group (RBG) space (may need larger RBG to save bits).

In both alternatives described above, the UE is aware of the approach in order to receive and process the grant.

Additionally or alternatively, a similar approach may be followed to provide a more irregular granting of resources in the frequency domain.

In yet another aspect regarding the design or implementation of PDCCH for <NUM> NR, the use of fast control signaling (also referred to as fast control channel signaling) for grant-free UL is proposed when <NUM> NR networks provide for UL applications having a grant-free option. For example, in machine type communication (MTC) or massive MIMO scenarios, when there are a lot of users, it may be desirable to have a grant-free UL approach to reduce the amount of overhead.

In the grant-free option described herein, there may be a pool of UL resources, both orthogonal (e.g., some FDM channels) and non-orthogonal (e.g., CDM/RSMA in each channels). The grant-free design may be used to let a UE hash to one of the resources in the pool without using a grant (e.g., to save grant time and resources). There is the potential for collisions if multiple UEs hash to the same resource.

A grant based implementation or design may also be used in addition to the grant-free option as an enhancement. In such a case, a UE may be granted with one of the resources in the pool for cases where, for example, the UE needs some higher quality-of-service (QoS).

The approaches described above may have an issue of potential collisions between granted UEs and grant-free UEs. That is, the grant-free UEs may not be aware of the granted UEs.

One solution is to add or include a fast control (channel) signaling to help the grant-free UEs identify empty (e.g., not granted) resources in the pool to reduce collision with the granted resources. This may be achieved by providing some dynamic signaling to control the hashing space of the grant-free UEs. Moreover, the signaling may be potentially transmitted in the PDCCH (e.g., faster approach) or may be RRC configured (e.g., slower approach).

In a first alternative, the eNB (or scheduling entity) may maintain a list of the available resources and may send a list of all empty (e.g., not granted) resources to the appropriate UEs. This approach may provide for an accurate resource control, but may require that the signaling be frequently transmitted (e.g., in PDCCH). Moreover, the signaling size might be large.

In a second alternative, the eNB (or scheduling entity) may divide the pool or resources into two parts, for granted and grant-free resources. The resources may be moved (or allocated) between the two parts dynamically and possibly slowly. The eNB may provide for some indication on the grant-free pool of resources in the signaling. If the resources are ordered, the granted resources may be used from the beginning, such that the eNB may only need to include the number of grant-free resources in the signaling.

The behavior of the UE in fast control (channel) signaling for grant-free UL described herein may involve having the grant-free UE decode the signaling, and hash to the available resources. Even if the UE cannot decode the (latest) signaling, resulting in a wrong hashing, the collision rate might be higher, and nothing breaks.

The behavior of the eNB (or scheduling entity) in fast control (channel) signaling for grant-free UL described herein may involve having the eNB send or transmit the signaling, but still try to detect the UL data in all resources. The eNB need not assume that the signaling is correctly received at the UE, which reduces the reliability requirement for the signaling.

Various aspects described above in connection with PDCCH for <NUM> NR are now described in more detail with reference to the <FIG>. Additionally, the term "component" as used herein may be one of the parts that make up a system, may be hardware, firmware, and/or software stored on a computer-readable medium, and may be divided into other components.

Referring to <FIG>, in accordance with various aspects of the present disclosure, an example wireless communication network <NUM> includes at least one UE <NUM> having a PDCC processing component <NUM>-b configured to perform one or more techniques described herein for PDCCH in <NUM> NR. A base station <NUM> or other scheduling entity may have a PDCCH signaling component <NUM>-a configured to perform one or more techniques described herein for PDCCH in <NUM> NR.

In an aspect, the PDCC scheduling component <NUM>-a may be configured to perform aspects or techniques described herein from the perspective of a network or scheduling entity (e.g., base stations <NUM>, eNB, zone, TRP, CCS). As such, the PDCCH scheduling component <NUM>-a may include a search space component <NUM> for handling multiple PDCCH space search techniques, a control RB component <NUM> for handling CRB techniques, an irregular grant component <NUM> for handling irregular multiple slots or mini-slots grants, and a fast control channel signal component <NUM> for handling fast control channel signaling for grant-free UL.

In another aspect, the PDCC processing component <NUM>-b may be configured to perform aspects or techniques described herein from the perspective of UE (e.g., UE <NUM>) or similar terminal device. As such, the PDCCH scheduling component <NUM>-b may include a search space component <NUM> for handling multiple PDCCH space search techniques, a control RB component <NUM> for handling CRB techniques, an irregular grant component <NUM> for handling irregular multiple slots or mini-slots grants, and a fast control channel signal component <NUM> for handling fast control channel signaling for grant-free UL.

The wireless communication network <NUM> may include one or more base stations <NUM>, one or more UEs <NUM>, and a core network <NUM>. As described above, the base stations <NUM> may be representative of different types of scheduling entities considered for purposes of this disclosure. Moreover, various network entities or devices in the wireless communication network <NUM> may be referred to as nodes through which a UE <NUM> can receive a PDCCH from a scheduling entity. For example, a node can be an eNB (or gNB) or base station. The core network <NUM> may provide user authentication, access authorization, tracking, internet protocol (IP) connectivity, and other access, routing, or mobility functions. The base stations <NUM> may interface with the core network <NUM> through backhaul links <NUM> (e.g., S1, etc.). The base stations <NUM> may perform radio configuration and scheduling for communication with the UEs <NUM>, or may operate under the control of a base station controller (not shown). In various examples, the base stations <NUM> may communicate, either directly or indirectly (e.g., through core network <NUM>), with one another over backhaul links <NUM> (e.g., X1, etc.), which may be wired or wireless communication links.

The base stations <NUM> may wirelessly communicate with the UEs <NUM> via one or more base station antennas. In some examples, base stations <NUM> may be referred to as a transmit/receive point (TRP), base transceiver station, a radio base station, an access point, a radio transceiver, a NodeB, eNodeB (eNB), Home NodeB, a Home eNodeB, a relay, or some other suitable terminology. The geographic coverage area <NUM> for a base station <NUM> may be divided into sectors or cells making up only a portion of the coverage area (not shown). The wireless communication network <NUM> may include base stations <NUM> of different types (e.g., macro base stations or small cell base stations, described below). Additionally, the plurality of base stations <NUM> may operate according to different ones of a plurality of communication technologies (e.g., <NUM> or <NUM> NR, <NUM>/LTE, <NUM>, Wi-Fi, Bluetooth, etc.), and thus there may be overlapping geographic coverage areas <NUM> for different communication technologies.

In some examples, the wireless communication network <NUM> may be or include a Long Term Evolution (LTE) or LTE-Advanced (LTE-A) technology network, or enhancements to such technology networks. The wireless communication network <NUM> may also be a next generation technology network, such as a <NUM> wireless communication network. Moreover, the wireless communication network <NUM> may support high frequency operations such as millimeter wave communications. In LTE/LTE-A networks, the term evolved node B (eNB) may be generally used to describe the base stations <NUM>, while the term UE may be generally used to describe the UEs <NUM>. The wireless communication network <NUM> may be a heterogeneous LTE/LTE-A network in which different types of eNBs provide coverage for various geographical regions. For example, each eNB or base station <NUM> may provide communication coverage for a macro cell, a small cell, or other types of cell. The term "cell" is a 3GPP term that can be used to describe a base station, a carrier or component carrier associated with a base station, or a coverage area (e.g., sector, etc.) of a carrier or base station, depending on context.

A macro cell may generally cover a relatively large geographic area (e.g., several kilometers in radius) and may allow unrestricted access by the UEs <NUM> with service subscriptions with the network provider.

A small cell may include a relative lower transmit-powered base station, as compared with a macro cell, that may operate in the same or different frequency bands (e.g., licensed, unlicensed, etc.) as macro cells. A pico cell, for example, may cover a small geographic area and may allow unrestricted access by the UEs <NUM> with service subscriptions with the network provider. A femto cell may also cover a small geographic area (e.g., a home) and may provide restricted access and/or unrestricted access by the UEs <NUM> having an association with the femto cell (e.g., in the restricted access case, the UEs <NUM> in a closed subscriber group (CSG) of the base station <NUM>, which may include the UEs <NUM> for users in the home, and the like). A micro cell may cover a larger geographic area than a pico cell or femto cell (e.g., a public building) and provide restricted access and/or unrestricted access by the UEs having an association with the micro cell. An eNB for a small cell may be referred to as a small cell eNB, a pico eNB, a femto eNB, micro eNB, or a home eNB.

The communication networks that may accommodate some of the various disclosed examples may be packet-based networks that operate according to a layered protocol stack and data in the user plane may be based on the IP. A radio link control (RLC) layer may perform packet segmentation and reassembly to communicate over logical channels. A MAC layer may perform priority handling and multiplexing of logical channels into transport channels. The MAC layer may also use HARQ to provide retransmission at the MAC layer to improve link efficiency. In the control plane, the radio resource control (RRC) protocol layer may provide establishment, configuration, and maintenance of an RRC connection between a UE <NUM> and the base stations <NUM>. The RRC protocol layer may also be used for core network <NUM> support of radio bearers for the user plane data. At the physical (PHY) layer, the transport channels may be mapped to physical channels.

The UEs <NUM> may be dispersed throughout the wireless communication network <NUM>, and each UE <NUM> may be stationary or mobile. A UE <NUM> may also include or be referred to by those skilled in the art as a mobile station, a subscriber station, a mobile unit, a subscriber unit, a wireless unit, a remote unit, a mobile device, a wireless device, a wireless communications device, a remote device, a mobile subscriber station, an access terminal, a mobile terminal, a wireless terminal, a remote terminal, a handset, a user agent, a mobile client, a client, or some other suitable terminology. A UE <NUM> may be a cellular phone, a personal digital assistant (PDA), a wireless modem, a wireless communication device, a handheld device, a tablet computer, a laptop computer, a cordless phone, a wireless local loop (WLL) station, an entertainment device, a vehicular component, or any device capable of communicating in wireless communication network <NUM>. Additionally, a UE <NUM> may be Internet of Things (IoT) and/or machine-to-machine (M2M) type of device, e.g., a low power, low data rate (relative to a wireless phone, for example) type of device, that may in some aspects communicate infrequently with wireless communication network <NUM> or other UEs. A UE <NUM> may be able to communicate with various types of base stations <NUM> and network equipment including macro eNBs, small cell eNBs, relay base stations, and the like.

A UE <NUM> may be configured to establish one or more wireless communication links <NUM> with one or more base stations <NUM>. The wireless communication links <NUM> shown in wireless communication network <NUM> may carry uplink (UL) transmissions from a UE <NUM> to a base station <NUM>, or downlink (DL) transmissions, from a base station <NUM> to a UE <NUM>. The downlink transmissions may also be called forward link transmissions while the uplink transmissions may also be called reverse link transmissions. Each wireless communication link <NUM> may include one or more carriers, where each carrier may be a signal made up of multiple subcarriers (e.g., waveform signals of different frequencies) modulated according to the various radio technologies described above. Each modulated signal may be sent on a different subcarrier and may carry control information (e.g., reference signals, control channels, etc.), overhead information, user data, etc. In an aspect, the communication links <NUM> may transmit bidirectional communications using frequency division duplex (FDD) (e.g., using paired spectrum resources) or time division duplex (TDD) operation (e.g., using unpaired spectrum resources).

In some aspects of the wireless communication network <NUM>, base stations <NUM> or UEs <NUM> may include multiple antennas for employing antenna diversity schemes to improve communication quality and reliability between base stations <NUM> and UEs <NUM>. Additionally or alternatively, base stations <NUM> or UEs <NUM> may employ multiple input multiple output (MIMO) techniques that may take advantage of multi-path environments to transmit multiple spatial layers carrying the same or different coded data.

The wireless communication network <NUM> may support operation on multiple cells or carriers, a feature which may be referred to as carrier aggregation (CA) or multicarrier operation. A carrier may also be referred to as a component carrier (CC), a layer, a channel, etc. The terms "carrier," "component carrier," "cell," and "channel" may be used interchangeably herein based on the appropriate context. A UE <NUM> may be configured with multiple downlink CCs and one or more uplink CCs for carrier aggregation.

Referring to <FIG>, a diagram <NUM> illustrates aspects related to the use of multiple PDCCH search spaces in <NUM> NR. As shown in the example in the diagram <NUM>, different search spaces can be defined for different scheduling entities. In this example, each of a scheduling entity <NUM> (<NUM>), a scheduling entity <NUM> (<NUM>), a scheduling entity <NUM> (<NUM>) all the way to a scheduling entity N (<NUM>) can have <NUM> or <NUM> search spaces defined. In this case, each of the scheduling entity <NUM> and the scheduling entity N has a common search space and a UE-specific search space defined. In contrast, the scheduling entity <NUM> has a common search space defined and the UE-specific search space can be optionally defined (dashed lines). Similarly, the scheduling entity <NUM> has a UE-specific search space defined and the common search space can be optionally defined (dashed lines). As described above, each of the scheduling entities shown in the diagram <NUM> can be one of different types of scheduling entities such as eNBs, cells, zones, TRPs, or CCS, for example.

<FIG> shows a diagram <NUM> illustrating the use of zones in <NUM> NR in accordance with an aspect of the disclosure. In an <NUM> NR system, a network may support various mobility procedures that may be beneficial in various conditions. A downlink based mobility mode may involve the UE measuring signals from one or more cells and the UE or network selecting a serving cell based on the UE measurements. An uplink based mobility mode may involve the UE transmitting an uplink measurement indication signal that the network uses to determine a serving cell for the UE. In uplink based mobility, cells may be organized into synchronized groups referred to herein as zones. As described above, a zone may be a scheduling entity for purposes of multiple PDCCH search spaces. The cells within a zone may form a single frequency network (SFN). One cell within the zone may be selected as the serving cell for a UE, but the UE does not need to be aware of which cell within the zone is the serving cell. Instead, the UE treats the zone as a serving zone. Uplink based mobility procedures for intra-zone mobility and inter-zone mobility may be different.

Similar downlink and uplink based mobility procedures may be adopted for zone mobility where a UE may transition from a serving zone to a target zone based on the measured signal quality between the UE and the serving base station. A zone may refer to a group or combination of cells that act together and are highly synchronized. Thus, a zone may include a plurality of cells operating on the same frequency and/or with the same timing, etc., such that a handover from one cell to another within the zone may be controlled by the network and be transparent to the UE.

Referring back to <FIG>, the diagram <NUM> shows a UE-centric MAC layer (UECM) network zone (e.g., zone_1) having a coverage area <NUM>-a and including at least a cell_1 having a coverage area <NUM>-b and a cell_2 having a coverage area <NUM>-c. The UECM network zone may be a zone associated with at least a portion of the wireless communication system <NUM> described above with in connection with <FIG>. A zone, such as zone_1, may refer to a group or combination of cells that act together and are highly synchronized. Because of the coordinated operation of the cells in a zone, the synchronization signals are zone-specific. That is, the synchronization signals transmitted (e.g., broadcast) from a zone are typically single-frequency network (SFN) synchronization signals. A single-frequency network is a broadcast network where several transmitters simultaneously send the same signal over the same frequency channel.

The use of zones in <NUM> NR networks or other next generation communication systems may be advantageous for mobility management operations. For example, when in a zone, cell reselection may be transparent to a UE. The network may be responsible for cell reselection and mobility, and the UE can be relieved from those responsibilities. Such an approach is not only efficient for the UE, it is also efficient for the network because the number of mobility messages that need to be exchanged with a UE are reduced.

The use of zones in <NUM> NR networks or other next generation communication systems may also enable certain applications such as massive MIMO, for example. Massive MIMO, which is also known as Large-Scale Antenna Systems, Very Large MIMO, Hyper MIMO, Full-Dimension MIMO and ARGOS, makes use of a very large number of service antennas (e.g., hundreds or thousands) that are operated fully coherently and adaptively. Extra antennas may help by focusing the transmission and reception of signal energy into smaller regions improving throughput and energy efficiency, in particularly when combined with simultaneous scheduling of a large number of user terminals (e.g., tens or hundreds). Massive MIMO was originally envisioned for TDD operation, but can potentially be applied also in FDD operation. Massive MIMO may provide additional benefits, including the use of inexpensive low-power components, reduced latency, simplification of the MAC layer, and robustness to interference and intentional jamming.

Also shown in <FIG> is a UE <NUM> located in an overlapping area or region between the UECM network zone and an nUECM network cell (e.g., cell_3 having coverage area <NUM>-d). The nUECM network cell may be a cell associated with at least a portion of a wireless communication system having a network-centric MAC layer. The UE <NUM> in the overlapping area may receive unified synchronization signals from base station <NUM>-a in cell_1 of zone_1 and/or from base station <NUM>-b in cell_3. In other words, the UE <NUM> in the overlapping area may receive synchronization signals from a UECM network zone (e.g., cell_1 in zone_1) and/or from an nUECM network cell (e.g., cell_3). For example, base station <NUM>-a may generate and transmit (e.g., broadcast), unified synchronization signals, which may identify zone_1 and/or cell_1, as well as a nominal tone spacing being used by zone_1. Moreover, base station <NUM>-b may transmit (e.g., broadcast) unified synchronization signals, which may identify cell_3.

After receiving the unified synchronization signals, whether from a UECM network zone or an nUECM network cell, the UE <NUM> in the overlapping area may process the unified synchronization signals to determine whether the network transmitting the signals is a UECM network or an nUECM network. The UE <NUM> may also detect, where the network is a UECM network, a nominal numerology (e.g., tone spacing) being used by the network. The UE <NUM> may detect the nominal numerology based on a number of copies of the unified synchronization signals received from a UECM network. In some aspects, the unified synchronization signals may identify the zone, but may not identify the cell from which the signal is transmitted.

Referring to <FIG>, a diagram <NUM> illustrates aggregation levels for multiple PDCCH search spaces. As described above, within each of the search space (e.g., common search space or UE-specific search space), the aggregation levels may be nested. The number of CCEs used for a PDCCH is also referred to as the aggregation level. For example, if aggregation level is <NUM>, a single CCE may be used for the PDCCH. If the aggregation level is <NUM>, two CCEs may be used for the PDCCH. Similarly for aggregation levels <NUM>, <NUM>, and <NUM> as shown in the diagram <NUM>. Regarding the nesting, if the aggregation level is <NUM> and CCEs #<NUM> and #<NUM> are being used (dark circles within dashed lines), it is possible to nest smaller aggregation levels, such as an aggregation level <NUM> for CCE #<NUM> and an aggregation level <NUM> for CCE #<NUM>. The number of CCEs aggregated for transmission of a particular PDCCH may be determined according to the channel conditions.

Referring to <FIG>, diagrams <NUM> and <NUM> are shown to illustrate alternative schemes to manage search space location. As described above, in a first alternative, each search space has its own REG/CCE space. The diagram <NUM> illustrates this by having each of a search space <NUM> (<NUM>), a search space <NUM> (<NUM>) all the way to a search space N (<NUM>) have its own REG/CCE space. For example and as shown, search space <NUM> has its respective REG/CCE space <NUM>, search space <NUM> has its respective REG/CCE space <NUM>, and search space N has its respective REG/CCE space N. Also as described above, in a second alternative, the same REG/CCE space may be shared across all search spaces as illustrated by the diagram <NUM>. In this case, each of a search space <NUM> (<NUM>), a search space <NUM> (<NUM>) all the way to a search space N (<NUM>) have a shared REG/CCE space.

Referring to <FIG>, and in connection with the CRB concept for PDCCH in <NUM> NR, diagrams <NUM> and <NUM> are shown to illustrate different examples of CBRs with <NUM> OFDM symbols. The diagram <NUM> shows a first example of a 12x2 CRB structure that includes <NUM> OFDM symbols, OFDM symbol <NUM> and OFDM symbol <NUM>, with <NUM> tones (resource elements or REs) in each OFDM symbol. Also shown in the diagram <NUM> are various reference signals (RS), also referred to as control reference signals, that can be included in the first OFDM symbol (e.g., OFDM symbol <NUM>). In this example, one RS is located in every other tone within the first OFDM symbol for a total of <NUM> RSs.

The diagram <NUM> shows a second example of a 16x2 CRB structure that includes <NUM> OFDM symbols, OFDM symbol <NUM> and OFDM symbol <NUM>, with <NUM> tones (resource elements or REs) in each OFDM symbol. Also shown in the diagram <NUM> are various reference signals (RS), also referred to as control reference signals, that can be included in the first OFDM symbol (e.g., OFDM symbol <NUM>). In this example, one RS is located in every other tone within the first OFDM symbol for a total of <NUM> RSs.

<FIG> is a flowchart illustrating an example method <NUM> in accordance with aspects of the disclosure. The operations described in connection with the method <NUM> may be performed by the PDCCH processing component <NUM>-b shown in <FIG> and <FIG>.

At block <NUM>, the method <NUM> includes identifying from information in a control channel, at a UE (e.g., UE <NUM>), a plurality of common search spaces on a carrier from one or more nodes. PDCCH can then be identified by monitoring the plurality of common search spaces.

The control channel can provide configuration information and/or indexing information (e.g., CCE indexing or CRB indexing) that can specify, or can be used to specify, the location (e.g., start, end, and/or range of allocated resources) for one or more common search spaces and/or one or more UE-specific search spaces for different types of scheduling entities (e.g., eNB, a cell, a zone, or a CCS). That is, a UE (e.g., UE <NUM>) can receive configuration information and/or indexing information to manage the location of search spaces and, based on the information, the UE can identify one or more common search spaces and/or UE-specific search spaces for different types of scheduling entities. In one aspect, the location of the search spaces can be dynamically updated (e.g., dynamically managed) by having the control channel provide updated information.

At block <NUM>, the method <NUM> includes monitoring the plurality of common search spaces.

At block <NUM>, the method <NUM> includes communicating with at least one of the one or more nodes based on the monitored plurality of common search spaces.

At block <NUM>, the method <NUM> may optionally or alternatively include identifying from the information in the control channel one or more UE-specific search spaces.

At block <NUM>, the method <NUM> may optionally or alternatively include communicating with at least one of the one or more nodes based on the one or more UE-specific search spaces.

The operations or functions associated with the blocks <NUM>, <NUM>, and <NUM> may be performed by, for example, the search space component <NUM>.

In another aspect of the method <NUM>, each of the plurality of common search spaces is associated with a respective scheduling entity.

In another aspect of the method <NUM>, the plurality of common search spaces comprise at least two of a cell-specific common search space, a zone-specific common search space, a CoMP common search space, where a zone associated with the zone-specific common search space or a CoMP set associated with the CoMP common search space comprises of a plurality of cells.

In another aspect of the method <NUM>, each of the plurality of common search spaces has its own REG/CCE space.

In another aspect of the method <NUM>, each of the plurality of common search spaces shares a same REG/CCE space.

In another aspect of the method <NUM>, at least two of the plurality of common search spaces are partially overlapped.

In another aspect of the method <NUM>, each of the plurality of common search spaces is associated with a respective cell identifier (ID).

Referring to <FIG>, a flowchart illustrating an example method <NUM> in accordance with aspects of the disclosure. The operations described in connection with the method <NUM> may be performed by the PDCCH processing component <NUM>-b shown in <FIG> and <FIG>.

Blocks <NUM>, <NUM>, and <NUM> in the method <NUM> are substantially the same as the respective blocks in the method <NUM> of <FIG>.

At block <NUM>, the method <NUM> may optionally or alternatively include identifying based on the information in the control channel multiple CRBs , each CRB having both RS and data REs, and where the RS and the data REs within each CRB are precoded using the same precoding.

The operations or functions associated with the block <NUM> may be performed by, for example, the control RB component <NUM>.

In another aspect of the method <NUM>, each of the multiple CRBs is precoded using the same beamforming.

In another aspect of the method <NUM>, each of the multiple CRBs is independently precoded.

In another aspect of the method <NUM>, the multiple CRBs are localized or distributed.

In another aspect of the method <NUM>, each CRB of the multiple CRBs is configured to support dual-stage control channel by having a first stage of the control channel in data REs in a first OFDM symbol of the CRB and a second stage of the control channel in data REs in a second OFDM symbol of the CRB.

At block <NUM>, the method <NUM> may optionally or alternatively include identifying based on information in the plurality of search spaces, resource blocks (RBs) granted across multiple slots, wherein the same RBs are granted across a subset of the multiple slots or arbitrary RBs are granted across all the multiple slots.

At block <NUM>, the method <NUM> may optionally or alternatively include identifying based on the information in the plurality of common search spaces over which slots of the multiple slots are the RBs granted.

The operations or functions associated with the blocks <NUM> and <NUM> may be performed by, for example, the irregular grant component <NUM>.

In another aspect of the method <NUM>, when the same RBs are granted across a subset of the multiple slots, the control channel includes a bitmap representative of an RB allocation pattern or an index representative of a predefined RB allocation pattern.

In yet another aspect of the method <NUM>, when arbitrary RBs are granted across all the multiple slots, the arbitrary RBs are sequentially numbered across the multiple slots.

<FIG> are flowcharts illustrating example methods of wireless communications using PDCCH in <NUM> NR in accordance with an aspect of the disclosure. <NUM>-a650-b.

In <FIG>, a method <NUM> for wireless communications and related to multiple PDCCH search spaces is shown that includes, at block <NUM>, identifying, at a UE, multiple types of scheduling entities supported by the UE.

At block <NUM>, the method <NUM> includes monitoring at least one PDCCH search space for each of the multiple types of scheduling entities.

The operations or functions associated with the blocks <NUM> and <NUM> may be performed by, for example, the search space component <NUM> in the PDCCH processing component <NUM>-b.

In <FIG>, a method <NUM> for wireless communications and related to control RB is shown that includes, at block <NUM>, generating multiple CRBs for PDCCH, each CRB having both a reference signal (RS) and data resource elements (REs).

At block <NUM>, the method <NUM> includes precoding the multiple CRBs such that the RS and the data REs within each CRB are precoded in the same fashion.

The operations or functions associated with the blocks <NUM> and <NUM> may be performed by, for example, the control RB component <NUM> in the PDCCH signaling component <NUM>-a.

In <FIG>, a method <NUM> for wireless communications and related to irregular multiple slot or mini-slot grants is shown that includes, at block <NUM>, identifying resource blocks (RBs) to be granted across multiple slots, wherein the same RBs are to be granted across a subset of the multiple slots or arbitrary RBs are to be granted across all the multiple slots.

At block <NUM>, the method <NUM> includes transmitting, in PDCCH, information about which RBs are to be granted and over which slots of the multiple slots.

The operations or functions associated with the blocks <NUM> and <NUM> may be performed by, for example, the irregular grant component <NUM> in the PDCCH signaling component <NUM>-a.

In <FIG>, a method <NUM> for wireless communications and related to fast control (channel) signaling for grant-free UL is shown that includes, at block <NUM>, identifying a portion of a pool of resources available for grant-free UL.

At block <NUM>, the method <NUM> includes transmitting a fast control channel including information that indicates the portion available for grant-free UL to one or more user equipment (UE) configured for grant-free UL.

The operations or functions associated with the blocks <NUM> and <NUM> may be performed by, for example, the fast control channel signal component <NUM> in the PDCCH signaling component <NUM>-a.

<FIG> is a block diagram illustrating an example of a device <NUM>, such as a UE, an eNB, or some other scheduling entity, that supports new implementations and designs for PDCCH in <NUM> NR in accordance with an aspect of the disclosure. <FIG> schematically illustrates hardware components and subcomponents for implementing one or more methods (e.g., methods <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>) described herein in accordance with various aspects of the present disclosure. In an example of an implementation, the device <NUM> may include a variety of components, some of which have already been described above, but including components such as one or more processors <NUM> and memory <NUM> and transceiver <NUM> in communication via one or more buses <NUM>, which may operate in conjunction with the PDCCH signaling component <NUM>-a (when the device <NUM> is a scheduling entity) or the PDCCH processing component <NUM>-b (when the device <NUM> is a UE or terminal device) to enable one or more of the functions described herein related to including one or more methods of the present disclosure. Further, the one or more processors <NUM>, modem <NUM>, memory <NUM>, transceiver <NUM>, RF front end <NUM> and one or more antennas <NUM>, may be configured to support voice and/or data calls (simultaneously or non-simultaneously) in one or more radio access technologies.

In an aspect, the one or more processors <NUM> can include a modem <NUM> that uses one or more modem processors. The various functions related to the PDCCH signaling component <NUM>-a or the PDCCH processing component <NUM>-b may be included in the modem <NUM> and/or the processors <NUM> and, in an aspect, can be executed by a single processor, while in other aspects, different ones of the functions may be executed by a combination of two or more different processors. For example, in an aspect, the one or more processors <NUM> may include any one or any combination of a modem processor, or a baseband processor, or a digital signal processor, or a transmit processor, or a receiver processor, or a transceiver processor associated with the transceiver <NUM>. In other aspects, some of the features of the one or more processors <NUM> and/or the modem <NUM> associated with the PDCCH signaling component <NUM>-a or the PDCCH processing component <NUM>-b may be performed by the transceiver <NUM>.

Also, the memory <NUM> may be configured to store data used herein and/or local versions of applications <NUM>, the PDCCH signaling component <NUM>-a, the PDCCH processing component <NUM>-b, and/or one or more of their subcomponents being executed by at least one processor <NUM>. The memory <NUM> can include any type of computer-readable medium usable by a computer or at least one processor <NUM>, such as random access memory (RAM), read only memory (ROM), tapes, magnetic discs, optical discs, volatile memory, non-volatile memory, and any combination thereof. In an aspect, for example, the memory <NUM> may be a non-transitory computer-readable storage medium that stores one or more computer-executable codes defining the PDCCH signaling component <NUM>-a, the PDCCH processing component <NUM>-b, and/or one or more of their subcomponents, and/or data associated therewith, when the device <NUM> is operating at least one processor <NUM> to execute the PDCCH signaling component <NUM>-a, the PDCCH processing component <NUM>-b, and/or one or more of their subcomponents (e.g., subcomponents of the PDCCH signaling component <NUM>-a, subcomponents of the PDCCH processing component <NUM>-b).

The transceiver <NUM> may include at least one receiver <NUM> and at least one transmitter <NUM>. The receiver <NUM> may include hardware, firmware, and/or software code executable by a processor for receiving data, the code comprising instructions and being stored in a memory (e.g., computer-readable medium). The receiver <NUM> may be, for example, a radio frequency (RF) receiver. In an aspect, the receiver <NUM> may receive signals transmitted by at least one base station <NUM> when, for example, the device <NUM> is a UE. Additionally, the receiver <NUM> may process such received signals, and also may obtain measurements of the signals, such as, but not limited to, Ec/Io, SNR, RSRP, RSSI, etc. The transmitter <NUM> may include hardware, firmware, and/or software code executable by a processor for transmitting data, the code comprising instructions and being stored in a memory (e.g., computer-readable medium). A suitable example of the transmitter <NUM> may include, but is not limited to, an RF transmitter.

Moreover, in an aspect, the device <NUM> may include an RF front end <NUM>, which may operate in communication with one or more antennas <NUM> and transceiver <NUM> for receiving and transmitting radio transmissions, for example. The RF front end <NUM> may be connected to one or more antennas <NUM> and can include one or more low-noise amplifiers (LNAs) <NUM>, one or more switches <NUM>, one or more power amplifiers (PAs) <NUM>, and one or more filters <NUM> for transmitting and receiving RF signals.

In an aspect, the LNA <NUM> can amplify a received signal at a desired output level. In an aspect, the RF front end <NUM> may use one or more switches <NUM> to select a particular LNA <NUM> and its specified gain value based on a desired gain value for a particular application.

Further, for example, one or more PA(s) <NUM> may be used by the RF front end <NUM> to amplify a signal for an RF output at a desired output power level. In an aspect, the RF front end <NUM> may use one or more switches <NUM> to select a particular PA <NUM> and a specified gain value for the particular PA <NUM> based on a desired gain value for a particular application.

Also, for example, one or more filters <NUM> can be used by the RF front end <NUM> to filter a received signal to obtain an input RF signal. Similarly, in an aspect, for example, a respective filter <NUM> can be used to filter an output from a respective PA 698to produce an output signal for transmission. In an aspect, the RF front end <NUM> can use one or more switches <NUM> to select a transmit or receive path using a specified filter <NUM>, LNA <NUM>, and/or PA <NUM>.

As such, the transceiver <NUM> may be configured to transmit and receive wireless signals through one or more antennas <NUM> via the RF front end <NUM>. In an aspect, the transceiver <NUM> may be tuned to operate at specified frequencies such that the device <NUM> can communicate with other devices. In an aspect, for example, the modem <NUM> can configure the transceiver <NUM> to operate at a specified frequency and power level based on the configuration of the device <NUM> and the communication protocol used by the modem <NUM>.

In an aspect, the modem <NUM> can be a multiband-multimode modem, which can process digital data and communicate with the transceiver <NUM> such that the digital data is sent and received using the transceiver <NUM>. In an aspect, the modem <NUM> can be multiband and be configured to support multiple frequency bands for a specific communications protocol. In an aspect, the modem <NUM> can be multimode and be configured to support multiple operating networks and communications protocols. In an aspect, the modem <NUM> can control one or more components of the device <NUM> (e.g., the RF front end <NUM>, the transceiver <NUM>) to enable transmission and/or reception of signals based on a specified modem configuration. In another aspect, the modem configuration can be based on configuration information associated with the device <NUM>.

Claim 1:
A method of wireless communications, the method comprising:
identifying from information in a control channel, at a user equipment, UE, a plurality of common search spaces on a carrier from one or more nodes, wherein each of the plurality of common search spaces is associated with a respective scheduling entity, and each of the plurality of common search spaces shares a same Resource Element Group/Control Channel Element REG/CCE space,
wherein each common search space of the plurality of common search spaces is arranged to hash to a different range of CCEs in the same REG/CCE space;
monitoring the plurality of common search spaces; and
communicating with at least one of the one or more nodes based on the monitored plurality of common search spaces.