PDCCH and CRS overlap in telecommunications systems

Abstract

The present disclosure proposes a process for improving NR PDCCH reception quality at a UE when transmitted in the same Orthogonal Frequency Division Multiplexing (OFDM) symbol and in the same frequency domain resource element as the LTE CRS. Using the capability parameters of the UE, the network node may transmit the LTE CRS and the NR PDCCH in the same OFDM symbol and the same frequency domain resource element using various coding schemes. The encoding scheme may be one or more of puncturing signaling, overlay signaling, relative power level, UE type, AL to adjust LTE CRS, or various combinations thereof. The UE may decode the PDDCH using the coding scheme. Through the present disclosure, legacy UEs may be supported by a network node for UE capabilities supported by coding selection. Network nodes may balance transmission reliability and available resources.

Description

Technical Field

[0001] This application is generally directed to LTE CRS signals and NR PDCCH, and more specifically to signaling when there is a potential conflict in their transmission resources. Background Art

[0002] During the development of the 3GPP Release (Rel) 15 specifications, there was a discussion to indicate the LTE CRS rate matching mode via NR DSS cell system information, however, there was no protocol to support idle mode CRS rate matching, and subsequently rate matching was performed only in connected mode and only specified for PDSCH. For example, according to 3GPP TS 38.213 "If at least one RE of a UE's PDCCH candidate on the serving cell overlaps with at least one RE of the LTE CRS-ToMatchAround or LTE CRS-PatternList, the UE is not required to monitor the PDCCH candidate.", the current 3GPP specifications do not allow NR PDCCH to overlap with LTE CRS. 3GPP has agreed to study an item in the Rel 18 specifications to alleviate the limitation to achieve higher NR PDCCH capacity, for example, Work Indication Item RP-213575. Summary of the invention

[0003] In one aspect, an apparatus is disclosed. In one embodiment, the apparatus includes (1) one or more processors, and (2) a memory storing instructions and data, which when executed by the one or more processors cause the apparatus to: (1) receive one or more of a Long Term Evolution (LTE) cell-specific reference signal (CRS) or a New Radio (NR) physical downlink control channel (PDCCH) from a network node, and (2) decode the NR PDCCH using a puncturing threshold and an aggregation level (AL), wherein the puncturing threshold indicates one or more of: puncturing signaling, superposition signaling, or NR PDCCH relative power level, wherein when the NR PDCCH relative power level is used, the NR PDCCH relative power level is received in a previous signal.

[0004] In a second aspect, an apparatus is disclosed. In one embodiment, the apparatus includes (1) one or more processors, and (2) a memory storing instructions and data, which when executed by the one or more processors cause the apparatus to: (1) determine a puncturing threshold for an NR PDCCH to a UE, wherein the puncturing threshold comprises an AL for the NR PDCCH when the apparatus is scheduled to transmit an LTE CRS in the same orthogonal frequency division multiplexing (OFDM) symbol and the same frequency domain resource element as the NR PDCCH, and (2) transmit the NR PDCCH to the UE, wherein the puncturing threshold is used to compose the NR PDCCH.

[0005] In a third aspect, a method is disclosed. In one embodiment, the method includes (1) receiving a capability parameter of a UE, wherein the capability parameter indicates whether the UE supports puncturing signaling of LTE CRS and NR PDCCH, (2) determining a puncturing threshold of the NR PDCCH using the capability parameter, wherein the puncturing threshold includes an AL for the PDCCH, and the LTE CRS is scheduled to be sent in the same OFDM symbol and the same frequency domain resource element as the NR PDCCH, (3) using the puncturing threshold to send the LTE CRS and the NR PDCCH to the UE, and (4) receiving the LTE CRS and the NR PDCCH at the UE.

[0006] In a fourth aspect, a communication system is disclosed. In one embodiment, the communication system includes (1) a network node capable of transceiving communications with one or more UEs, wherein the communications include LTE CRS and NR PDCCH, and the LTE CRS and NR PDCCH are sent using one of puncturing signaling, superposition signaling, or drop signaling, wherein the LTE CRS is sent in the same OFDM symbol and the same frequency domain resource element as the NR PDCCH, and (2) a UE among the one or more UEs capable of transceiving communications with the network node, wherein the UE sends a capability parameter to the network node, the UE receives a puncturing threshold from the network node, and the UE uses the puncturing threshold to process the LTE CRS and decode the NR PDCCH. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Reference is now made to the following description in conjunction with the accompanying drawings, in which:

[0008] Figure 1 is an illustration of an example communication scenario with a network node and multiple user equipments (UEs);

[0009] Figure 2 is a diagram of example diagrams of puncture signaling and overlay signaling;

[0010] Figure 3 is an illustration of a flow chart of an example method of determining puncturing or overlay signaling;

[0011] Figure 4 is an illustration of a block diagram of an example communication system; and

[0012] Figure 5 is an illustration of a block diagram of an example of a signal controller according to the principles of the present disclosure. DETAILED DESCRIPTION

[0013] In the fifth generation (5G) 3rd Generation Partnership Project (3GPP) Release 18 (Rel 18) proposed standard, there is a work item (WI) marked as RP-21375 for RAN#94 in December 2022. The objectives of the 3GPP Rel 18 Dynamic Spectrum Sharing (DSS) WI are stated as (1) studying and, if needed, specifying new radio (NR) physical downlink control channel (PDCCH) reception in symbols with long term evolution (LTE) cell specific reference signal (CRS) resource elements (REs) [RAN1], (2) studying enabling LTE CRS to puncture NR PDCCH, including the impact on NR PDCCH demodulation reference signal (DMRS) if there is a performance gain from additional PDCCH resources, and (3) allowing user equipment (UE) to support and be configured with two overlapping CRS rate matching modes regardless of whether multiple transmit receive points (TRPs) are supported or configured [RAN1, RAN2]. The WI is planned to span two RAN1 meetings in May and August 2022. Acceptable solutions from this study item may be reflected in various 3GPP specifications.

[0014] In a communication network, a UE can establish a communication connection with a network node. UE, such as a mobile phone, tablet, laptop, vehicle, ship, train, satellite, balloon, aircraft, spacecraft and other 5G devices (whether movable, mobile or stationary), can establish a communication link with one or more network nodes (i.e., network devices). A network node can implement a communication node, such as a radio access network (RAN), such as a 5G base station (gNB), an evolved universal mobile telecommunications system (UMTS), a terrestrial radio access (E-UTRA), an enhanced 4GeNodeB E-UTRA base station (eNB), such as an enhanced node B, an enhanced gNB (en-gNB) or a next generation eNB (ng-eNB). The network node can be implemented using various terrestrial or non-terrestrial systems (e.g., ground-based systems, balloons, aircraft, satellites, spacecraft and other non-terrestrial systems). The network nodes may be, for example, low earth orbit (LEO) satellites, medium earth orbit (MEO) satellites, geosynchronous orbit (GEO) satellites, high altitude platform stations (HAPS), unmanned aerial vehicles (UAVs), unmanned aircraft systems (UASs), or other types of platforms or vehicles.

[0015] When deploying previous 4G or 5G Dynamic Spectrum Sharing (DSS) schemes, one of the rationales was to minimize the impact on the legacy LTE network. This led to the deployment of DSS in low frequency bands where NR has very limited PDCCH resources. This shortcoming was also addressed in Rel 17WI for cross-carrier scheduling from SCell to PCell. Cross-carrier scheduling can be a complex feature and the probability of it being adopted by the ecosystem seems low, at least for DSS use cases. On top of the carrier aggregation feature, cross-carrier scheduling may require separate UE capabilities.

[0016] Typically, in the DSS, NR is configured to operate with a 15 kilohertz (kHz) subcarrier spacing (SCS), the same SCS used by LTE. Another convention commonly used is that LTE subframes and NR subframes (e.g., respective time slots) are aligned in time and frequency. The current 3GPP specification does not allow NR PDCCH to overlap with LTE CRS. The PDCCH monitoring opportunities defined by monitoringSymbolsWithinSlot (monitoring symbols in a time slot) (in IE SearchSpace of TS 38.331) cannot overlap with LTE CRS. For example, when LTE is configured with a 4-port CRS, there may be 12 symbols per physical resource block (PRB) available for NR PDCCH. This is an optional feature for the UE to monitor the PDCCH in the symbols of the time slot. This corresponds to operation according to feature group (FG) 3-5, while the UE supports FG3-1 in which PDCCH monitoring is constrained to the first 3 symbols of the time slot. With a 4-port CRS configuration, there will be one symbol available for PDCCH. Therefore, PDCCH capacity is the bottleneck of DSS deployment.

[0017] The present disclosure provides a process for implementing transmission of LTE CRS and NR PDCCH during the same orthogonal frequency division multiplexing (OFDM) symbol and the same frequency domain resource element. The transmission can be encoded (composed) using superimposed signaling of NR PDCCH on LTE CRS (i.e., both are sent, and NR UEs interested in NR PDCCH experience LTE CRS as interference, and LTE UEs interested in LTE CRS experience overlapping NR PCCCH REs as interference), or puncturing NR PDCCH REs that overlap with LTE CRS (NR PDCCH transmissions do not use REs that overlap with LTE CRS, so NR UEs do not use these overlapping symbols in NR PDCCH demodulation / decoding). The operation used by the UE can be a function of the aggregation level (AL) of the PDCCH candidate or PDSCH candidate being processed. Simulations show that for low ALs, the effectiveness of PDCCH superimposed signaling is lower, so puncturing signaling can be the preferred process. For higher ALs, superimposed signaling can be preferred over puncturing signaling. The crossover point between puncturing signaling and overlay signaling may depend on the relative transmit (Tx) powers of the NR PDCCH and LTE CRS and the target PDCCH block error rate (BLER) operating point. The present disclosure may relate to DSS features. Spectrum sharing means that multiple radio access technologies share the same spectrum. In the demonstration scenario presented herein, the two radio access technologies sharing the same spectrum are LTE and NR. Dynamic means that the channel allocation is not static and varies in time or frequency, for example, from one subframe or time slot to another.

[0018] In some aspects, in addition to the LTE CRS pattern, the gNB (i.e., one of the various types of network nodes) may configure the UE with information about for which NRPDCCH candidate ALs the UE may assume that the NR PDCCH will be punctured on REs overlapping with the LTE CRS, and for which ALs no puncturing is performed. This aspect is part of PDCCH detection, where the UE decodes each PDCCH candidate using a predefined control channel element (CCE). Different PDCCH candidates may have a predefined starting CCE and occupy a predefined number of consecutive CCEs defined by the AL. Two different UE types may be employed, (1) UEs that support puncture signaling for NRPDCCH to make room for LTE CRS, such as Rel-18 UEs, and (2) UEs that do not support puncture signaling for PDCCH (e.g., legacy UEs and newer UEs that do not support this functionality).

[0019] In some aspects, when PDCCH overlaps with CRS, the gNB may schedule legacy UEs with a higher AL and avoid using a low AL. For legacy UEs, this may be possible if the LTE CRS configuration is not provided to the UE, or the CRS configuration does not tell the UE that there are CRS REs overlapping with PDCCH.

[0020] In some aspects, the gNB may schedule newer UEs that do not support puncturing decoding capability, or are configured with puncturing decoding capability in the operating mode. Scheduling may be done in the same manner as legacy UEs, and the newer UEs will know that when a PDCCH candidate overlaps with an LTE CRS, a low AL will not be used (as configured), and blind decoding may be skipped (e.g., NR PDCCH skipping), leaving blind decoding budget for other ALs. In some aspects, the newer UEs will accept LTE CRS pattern configurations that result in PDCCH overlapping with LTE CRS, a scenario that legacy UEs do not want to accept.

[0021] In some aspects, the gNB may freely select ALs for new UEs with punctured decoding support. For example, for each search space, the gNB may configure the number of PDCCH candidates per AL that the UE should monitor at predefined PDCCH monitoring occasions. This may be configured by the SearchSpace information element, as described in TS 38.331.

[0022] When decoding low AL PDCCH candidates (where low AL is related to the equipment used and the power of each signal), the UE can use punctured decoding and will not assume that the NR PDCCH is present on REs that overlap with LTE CRS REs. When decoding higher AL PDCCH, the UE will not use punctured decoding, and in some aspects, the UE can use CRS interference suppression.

[0023] In some aspects, at least the NR UE may be configured with relative power levels of the superimposed REs so that the UE knows the LTE CRS interference power relative to the NR PDCCH or PDCCH DMRS REs when both fall on the same resource element. The configuration may indicate that the NR PDCCH is higher power, equivalent power, or lower power than the LTE CRS down to negative infinity (where power is measured in decibels (dB)), which would correspond to puncturing the NR PDCCH or PDCCH DMRS REs that collide with the LTE CRS (e.g., the puncturing threshold specifies a DMRS to LTE CRS collision parameter). The NR UE may know the relative power of the PDCCH or PDCCH DMRS REs that do not collide with the LTE CRS.

[0024] In some aspects, when the UE expects better performance, the gNB will not puncture the NR PDCCH, and the UE will use its knowledge of the superimposed signaling and its relative power. For example, the gNB can send PDCCH REs on LTE CRS, and the UE can ignore them. The gNB does not know when the UE will use or ignore REs. In a specific example, a UE that can suppress CRS interference can use superimposed REs on a specific AL with a given PDCCH / CRS power ratio, while another UE that cannot suppress CRS interference will use punctured decoding under the same conditions.

[0025] In some aspects, a set of reference UE types may be specified, e.g., capable of CRS interference suppression, or not capable of CRS interference suppression, and the UE type will be provided to the gNB as a UE capability parameter. The capability may inform at which AL with a given NR to LTE CRS power ratio the puncturing signaling will be used. This may allow the gNB to not send PDCCH REs that the UE will not use during decoding. In some aspects, the puncturing decoding vs. non-puncturing decoding behavior of the UE may be bilaterally negotiated, and upon UE type detection (using the capability parameter), the gNB will know in which scenarios the UE will apply puncturing decoding for signaling.

[0026] Thus, in some aspects, a network node may adjust the NR PDCCH power (e.g., setting the NR PDCCH relative power level), for example, using execution parameters, to obtain a balance between the degree of interference of the NR PDCCH to the LTE CRS and the degree of improvement in the NR PDCCH performance (relative to puncturing decoding). It is expected that operators may be concerned about the impact on LTE performance caused by CRS interference in basic scenarios. In networks with lower LTE traffic and higher NR device penetration, operators may emphasize NR PDCCH capacity and performance in combination with more signal balancing, but at the expense of higher LTE CRS interference when overlapping with PDCCH transmissions. The UE knows the power difference between the clean PDCCH symbols and the interfered PDCCH symbols and the amount of LTE CRS interference on the interfered symbols, and can exploit this in the receive processing to obtain optimal decoding performance.

[0027] In some aspects, UE demodulation performance requirements may be defined separately for different DSS overlay signaling scenarios (e.g., for different power levels and different collision scenarios). Some disclosed aspects may include various combinations of: (1) overlay signaling of downlink (DL) control signals, (2) overlay signaling of PDCCH REs versus puncturing signaling based on PDCCH AL, (3) overlay signaling versus discarding PDCCH candidates if the PDCCH candidate overlaps with LTE CRS, depending on AL (for UEs that do not support puncturing signaling), (4) a power control-based scheme for mitigating interference from one radio access technology (RAT) to another RAT based on various factors (e.g., connected UEs and their radio conditions), (5) network node UE channel estimation biasing based on power control of another node's control signal, and (6) overlay signaling and indication of interference power relative to a desired signal for the UE for channel estimation and decoding purposes.

[0028] In some aspects, the following or variations thereof may be utilized in the 3GPP standard, wherein an NR UE configured with an LTE CRS mode shall (1) not attempt to decode the PDCCH candidate for a particular AL if the PDCCH candidate for the particular AL overlaps with an LTE CRS RE, such as a newer UE that does not support puncturing signaling, depending on the configuration, and (2) not use REs overlapping with LTE CRS REs (punctured REs) when decoding PDCCH or PDSCH candidates for the particular AL if the PDCC candidate for the particular AL overlaps with an LTE CRS RE, such as a newer UE that supports puncturing signaling, depending on the RRC configuration. For demonstration purposes, an example of a messaging change for the 3GPP standard is shown in Table 1. Other messaging changes and different messaging changes may be utilized to implement the present disclosure; for example, Table 1.

[0029] Table 1: Example message transmission supporting puncturing signaling In some aspects, coexistence with legacy UEs may be supported, such as UEs that do not support configurations where PDCCH overlaps with LTE CRS. Typically, current 3GPP specifications do not support PDCCH candidates that overlap with LTE CRS REs. In some aspects, before the release of the Rel 18 standard for UEs that do not support PDCC puncturing and support overlay signaling, support for this overlap may be extended to an existing device base through a software upgrade, for example, the UE may accept the configuration where NR PDCCH candidates are mapped to LTE CRS REs and attempt to decode the PDCCH candidate. In attempting to support aspects of the present disclosure prior to Rel-18, it may be possible to test or verify whether legacy UE devices can support the disclosed solution. For example, a solution may be developed through interoperability device testing (IoDT), where UE vendors may bilaterally disclose support configurations for specific UE types and will attempt to decode such PDCCH candidates. These tested or verified UEs may be identified by UE capability parameters or by a reused UE capability indicator that has been marked as obsolete.

[0030] In some aspects, the following process may be applied in the case of coexistence with legacy UEs that do not support configurations for PDCCH overlap with LTE CRS. In some aspects, idle mode UEs may not be aware that LTE CRS is present, and therefore these UEs may attempt to decode PDCCH candidates even if they overlap with LTE CRS. This mode of operation may be equivalent to no puncturing signaling in the case where the UE receiver does not attempt to mitigate the presence of CRS, because the UE will not be able to suppress CRS interference or avoid CRS-contaminated DMRS REs in the channel estimate. This aspect may be used for legacy UEs in connected mode, although the mode of operation may not improve PDCCH or PDSCH performance through LTE CRS rate matching.

[0031] In some aspects, when the PDCCH precoder granularity is not set to contiguous resource blocks (RBs), the UE may accept the configuration and discard PDCCH candidates that overlap with LTE CRS. With this configuration, the gNB may avoid those PDCCH candidates with overlapping REs. This aspect may have limitations due to discarding PDCCH candidates from transmission.

[0032] In some aspects, even if the current LTE CRS is 4-port, legacy UEs can be configured with 2-port LTE CRS to rate match the surrounding. This will reduce the PDCCH or PDSCH performance on the REs overlapping with CRS ports #2 and #3. However, if there is still a symbol with LTE CRS REs, that symbol can be used for PDCCH monitoring. In some aspects, legacy UEs can operate in a conventional manner so that they can be configured with a narrow control resource set (CORESET) and will therefore suffer from low PDCCH capacity.

[0033] If NR DSS cells are allowed to send NR PDCCH on REs overlapping with LTE CRS, this may impact legacy LTE UE channel estimation, timing / frequency synchronization and measurements. In the case of 4-port LTE CRS with 2 NR PDCCH symbols, 4 LTE CRS REs are affected per physical RB out of a total of 8 physical RBs on ports 2 and 3. The interference on ports 2 and 3 may not impact the traffic performance of idle mode LTE UEs, and since mobility measurements should also not use the CRS of ports #2 and #3, it should not impact idle mode or connected mode mobility. LTE and NR networks can operate on the same licensed band on the same carrier frequency in the same geographical location, i.e., they belong to the same network operator, which can then control the radio technology it wishes to prioritize on the carrier.

[0034] The proposed procedure may enable legacy NR UEs to operate with minor changes, such as monitoring search spaces that overlap with LTE CRS. A legacy UE in a DSS cell may not be aware of the presence of LTE CRS on the NR DSS cell until after entering connected mode, so the legacy UE may at least initially monitor CORESET0 regardless of the presence or absence of overlapping LTE CRS. After entering connected mode, the UE implementation determines whether to further monitor these search spaces.

[0035] In some aspects, to further improve the performance of NR UEs in DSS scenarios with LTE CRS overlapping with PDCCH resources, the presence of overlapping resources can be notified to the NR UE. For example, the NR UE can be notified about the overlap of REs with CORESETs, as well as parameters indicating the LTE CRS power relative to the NR PDCCH. This information can be provided to the UE semi-statically based on the AL, for example, different relative powers per AL. Using this information, the NR UE can change its PDCCH monitoring behavior, such as not discarding the PDCCH, and apply this information to modify its receiver, channel estimation, or PDCCH decoding algorithm. For example, the PDCCH receiver can modify its channel estimation principle to (1) perform channel estimation from clean symbols, (2) perform channel estimation from symbols, or (3) perform channel estimation from DMRS without CRS superimposed signaling.

[0036] The present disclosure may allow UE vendors to minimize UE complexity for Rel-18 DSS features, e.g., no puncturing for LTE CRS in channel estimation for NR PDCCH. Legacy UE platforms may benefit from this framework with simple changes. Solutions such as puncturing signaling will not benefit pre-Rel-18 UEs and therefore cannot easily resolve the PDCCH bottleneck. Network operators may (1) increase PDCCH capacity while minimizing complex configuration, (2) reduce implementation barriers for Rel-18 DSS features, or (3) have additional tools for balancing LTE and NR performance.

[0037] Now turning to the attached figure, Figure 1 1 is a schematic diagram of an example communication scenario 100 with a network node and multiple UEs. Communication scenario 100 is an illustration of an environment of the present disclosure. The environment for communication scenario 100 includes UE 110a, UE 110b, UE 110c (collectively referred to as UE 110) and network node 120. There may be fewer or more UEs in UE 110. Network node 120 may be a gNB or other type of communication node.

[0038] A set of example messages is shown in the communication scenario 100. At a registration time, a configuration change time, or after a message transmission request at UE 110a, UE 110a may send a message 130a to the network node 120 using the configuration parameters of UE 110a. Message 130a may include one or more configuration parameters, such as support for puncturing signaling or support for relative power ratio. Similarly, UE 110b may send its configuration parameters via message 130b, and UE 110c may send its configuration parameters via message 130c (collectively referred to as message 130). Message 130 may be a variety of messages or a response to a PDCCH or PDSCH message.

[0039] In some exemplary aspects, the network node 120 may determine whether to use puncturing signaling or superposition signaling for future PDCCHs. In some exemplary aspects, the network node 120 may determine whether to use NR PDCCH relative power levels to reduce signal interference. The PDCCH and LTE CRS may be sent to the UE 110 using a message 140a for UE 110a, a message 140b for 110b, and a message 140c for 110c (collectively referred to as messages 140), for example, using puncturing signaling or superposition signaling. Each UE in the UE 110 may utilize a different transmission scheme. In some exemplary aspects, the message 140 may be received, and each UE 110 may adjust its respective decoding scheme for a subsequent PDCCH.

[0040] Figure 2 FIG200 is a schematic diagram of an example of puncturing signaling and superposition signaling. FIG200 depicts some different NR PDCCH configurations in an LTE slot. FIG200 has two parts, a 1-symbol CORESET 210 and a 2-symbol CORESET 230. FIG200 depicts two collision scenarios. Signaling 215 utilizes a 2-port CRS and shows that there is no collision in symbol slot 1. Signaling 217 shows that in a 4-port CRS, there may be symbol interference in symbol slot 2, so puncturing or superposition signaling will be used. Signaling 235 uses a 2-port CRS and shows that there is no collision in symbol slot 2 or symbol slot 3. Signaling 237 utilizes a 4-port CRS and shows that there may be interference in symbols in slot 2, but there is no collision in symbol slot 3. In the symbols where the collision occurs, one NR PDCCH DMRS and three NR PCCCH data REs per PRB are affected.

[0041] Figure 3 is an illustration of a flow chart of an example method 300 for determining puncturing or overlay signaling. The method 300 may be executed on a computing system such as Figure 1 The network node 120 of the communication scenario 100, Figure 4Communication system 400 or Figure 5 signal controller 500. Method 300 may be performed by a UE, a network node, or partially by a UE and partially by a network node. In some exemplary aspects, the UE may receive a signal configuration, such as a puncturing threshold, from a network node. In some aspects, the puncturing threshold may be configured by high-layer signaling. In some exemplary aspects, a network node may receive configuration parameters. Method 300 may be encapsulated in software code or hardware (e.g., an application, a code library, a dynamic link library, a module, a function, RAM, ROM, and other software and hardware implementations). The software may be stored in a file, a database, or other computing system storage mechanism. Method 300 may be implemented partially in software and partially in hardware. Method 300 may perform the steps of the process, for example, determining whether to send PDCCH or PDSCH using puncturing signaling, superposition signaling, or using relative power levels.

[0042] Method 300 starts at step 305 and proceeds to step 310. In step 310, the network node may receive capability parameters from a connected UE. The capability parameters may specify whether the UE supports puncturing signaling, supports overlay signaling, or supports relative power ratio levels. In some aspects, the capability parameters may specify a preferred AL level to help the network node determine which signaling scheme to use. In some aspects, the capability parameters may specify the type of UE or the capabilities of the UE so that the network node can estimate the UE capabilities when determining the transmission scheme for the PDCCH. Step 310 may be optional, in which case the network node may use other factors such as available resources to estimate the transmission scheme. In some aspects, the gNB may implicitly utilize other received signaling to determine the UE capabilities.

[0043] In step 315, the network node determines the signaling scheme to be used for the PDCCH. Figure 3 NR PDCCH transmissions are shown, but overlapping LTE CRS transmissions are not specifically shown. The selected signaling scheme utilizes the content shown and other information, such as LTE CRS transmissions. In some aspects, the network node can specify that the NR PDCCH relative power level is to be used for subsequent PDCCHs. In decision step 320, if puncturing signaling is being used for PDCCH, the result is "yes" and the method 300 proceeds to step 325. If the result is "no", the method 300 proceeds to step 330.

[0044] In step 325, the network node constructs the PDCCH using a puncturing signaling scheme, and the transmission includes LTE CRS information, such as the number of CRS ports, cell identifiers, and other parameters. The method 300 enters step 335. In step 330, the network node constructs the PDCCH using superposition signaling, and the transmission includes LTE CRS information. For example, the power level used for LTE CRS transmission, and other parameters in some aspects, such as the number of CRS ports, cell identifiers, or other LTE CRS parameters. In some aspects, the network node can change the power level used for the NR portion of the signal based on a previously determined NR PDCCH relative power level (e.g., a power level ratio of NR to LTE CRS). The ratio can indicate that the NR PDCCH relative power level is at a higher power level, a lower power level, or an equal power level relative to the LTE CRS. The method 300 enters step 335.

[0045] In step 335 , the network node transmits the PDCCH using an appropriate scheme. The UE receives the PDCCH and decodes the signal accordingly. The method 300 ends at step 395 .

[0046] Figure 4 is an illustration of a block diagram of an example communication system 400. The communication system 400 is an example system and may have additional network nodes and additional UEs. The communication system 400 may implement the disclosed solution, for example Figure 3 The method 300 is implemented Figure 5 The communication system 400 includes a UE 410 and a network node 430.

[0047] UE 410 has a transceiver 420 that can receive communication signals and send communication signals with network node 430 using signal connection 480, such as receiving a signal configuration (e.g., a puncturing threshold) or sending configuration parameters from network node 430. UE 410 has a signal decoder 425 that can determine how UE 410 decodes the PDCCH using the received signal configuration.

[0048] The network node 430 has a transceiver 440 that can receive communication signals and send communication signals with the UE 410 using a signal connection 480. The network node 430 has a signal encoder 445 that can analyze the received UE configuration parameters (in terms of receiving the configuration parameters) and can encode the PDCCH using one or more schemes described herein. In some aspects, the configuration parameters are not sent by the UE 410, and the network node 430 uses a decision algorithm to determine the transmission scheme to be used, such as using known factors of the UE 410 (such as the model or type of the UE) to perform an estimate. The network node 430 can deliver the PDCCH to the UE 410 using one of the schemes described herein.

[0049] Elements of UE 410 and network node 430 are shown as functional views, which may be implemented by software, hardware, or a combination thereof. In some aspects, the functions shown may be combined with other functions of the corresponding UE 410 or network node 430.

[0050] Figure 5 5 is an illustration of a block diagram of an example of a signal controller 500 according to the principles of the present disclosure. The signal controller 500 may be stored on a single computer or on multiple computers. The various components of the signal controller 500 may communicate via wireless or wired conventional connections. In some aspects, part or all of the signal controller 500 may be located as part of a UE, and other parts of the signal controller 500 may be located as part of a network node that communicates with the UE. In some aspects, the entire signal controller 500 may be implemented in a network node. When hosted on another system or process, the signal controller 500 may be virtual or partially virtual.

[0051] The signal controller 500 may be configured to perform various functions disclosed herein, including receiving UE configuration parameters. The various functions performed may be execution of the methods and processes described herein, such as Figure 3 The signal controller 500 may implement Figure 4 The communication system 400 of FIG. 5 is a signal controller 500 including a communication interface 510 , a memory 520 and a processor 530 .

[0052] The communication interface 510 is configured to send and receive data. For example, the communication interface 510 may receive configuration parameters from the UE. The communication interface 510 may send a PDCCH or a PDSCH. The communication interface 510 may communicate via a communication system used in the industry. For example, a wireless or wired protocol may be used. The communication interface 510 may perform operations for Figure 4 The operations described in transceiver 420 or transceiver 440.

[0053] The memory 520 may be configured to store a series of operating instructions and data, such as storing instructions and data that guide the operation of the processor 530 when initiated, including code representing a method for determining a transmission scheme for a PDCCH or PDSCH. The memory 520 is a non-transitory computer-readable medium. Various types of memory may be used for data storage, and the memory 520 may be distributed.

[0054] The processor 530 may be configured to determine an appropriate method for encoding a combination of NR and LTE CRS signals. For example, the processor 530 may determine whether the signal will be encoded (e.g., composed) using puncturing signaling, superposition signaling, relative power ratio levels, or a combination thereof. The processor 530 may be configured to direct the operation of the signal controller 500. The processor 530 includes logic in communication with the communication interface 510 and the memory 520 and performs the functions described herein. The processor 530 is capable of executing or directing Figure 4 The operations described by the signal decoder 425 or the signal encoder 445 are described.

[0055] A portion of the above-described apparatus, system, or method may be implemented or executed in a variety of analog or digital data processors, wherein the processor is programmed or stores an executable program of a sequence of software instructions to perform one or more steps of the method. The processor may be, for example, a programmable logic device, such as a programmable array logic (PAL), a general array logic (GAL), a field programmable gate array (FPGA), or another type of computer processing device (CPD). The software instructions of such a program may represent a scheme and be encoded in a machine-executable form on a non-transitory digital data storage medium (e.g., a disk or optical disk, a random access memory (RAM), a magnetic hard disk, a flash memory, or a read-only memory (ROM)) to enable various types of digital data processors or computers to perform one, more, or all steps of one or more of the above-described methods, functions, systems, or apparatuses described herein.

[0056] Portions of the disclosed examples or embodiments may involve a computer storage product with a non-transitory computer-readable medium having program code thereon for performing various computer-implemented operations that embody a portion of an apparatus, device, or perform steps of a method described herein. Non-transitory as used herein refers to all computer-readable media except transient propagating signals. Examples of non-transitory computer-readable media include, but are not limited to: magnetic media, such as hard disks, floppy disks, and magnetic tapes; optical media, such as CD-ROM discs; magneto-optical media, such as floppy disks; and hardware devices specifically configured to store and execute program code, such as ROM and RAM devices. Examples of program code include machine code, such as produced by a compiler, and files containing higher-level code that can be executed by a computer using an interpreter.

[0057] In interpreting the present disclosure, all terms should be interpreted in the broadest possible manner consistent with the context. In particular, the terms "include" and "comprising" should be interpreted as referring to elements, components or steps in a non-exclusive manner, indicating that the referenced elements, components or steps may exist or be used, or be combined with other elements, components, steps not explicitly referenced.

[0058] Those skilled in the art to which this application belongs will understand that other and further additions, deletions, substitutions and modifications may be made to the described embodiments. It should also be understood that the terms used herein are only used to describe specific embodiments and are not intended to be limiting, as the scope of the present disclosure will be limited only by the claims. Unless otherwise defined, all technical and scientific terms used herein have the same meanings as those of ordinary skill in the art to which this disclosure belongs. Although any methods and materials similar or equivalent to the methods and materials described herein may also be used in the practice or testing of the present disclosure, a limited number of exemplary methods and materials are described herein.

[0059] As described in the Summary of the Invention section, aspects disclosed herein include:

[0060] A. An apparatus comprising (1) one or more processors, and (2) a memory storing instructions and data that, when executed by the one or more processors, cause the apparatus to: (1) receive one or more of an LTE CRS or an NR PDCCH from a network node, and (2) decode the NR PDCCH using a puncturing threshold and an AL, wherein the puncturing threshold indicates one or more of: puncturing signaling, superposition signaling, or an NR PDCCH relative power level, wherein when the NR PDCCH relative power level is used, the NR PDCCH relative power level is received in a previous signal.

[0061] B. An apparatus comprising (1) one or more processors, and (2) a memory storing instructions and data that, when executed by the one or more processors, cause the apparatus to: (1) determine a puncturing threshold for an NR PDCCH to a UE, wherein the puncturing threshold comprises an AL for the NR PDCCH when the apparatus is scheduled to send an LTE CRS in the same OFDM symbol and the same frequency-domain resource element as the NR PDCCH, and (2) send an NR PDCCH to the UE, wherein the puncturing threshold is used to construct the NR PDCCH.

[0062] C. A method, comprising (1) receiving a capability parameter of a UE, wherein the capability parameter indicates whether the UE supports puncturing signaling of an LTE CRS and an NR PDCCH, (2) determining a puncturing threshold of the NR PDCCH using the capability parameter, wherein the puncturing threshold includes an AL for the PDCCH, and the LTE CRS is scheduled to be sent in the same OFDM symbol and the same frequency domain resource element as the NR PDCCH, (3) sending the LTE CRS and the NR PDCCH to the UE using the puncturing threshold, and (4) receiving the LTE CRS and the NR PDCCH at the UE.

[0063] D. A communication system, comprising (1) a network node capable of transceiving communications with one or more UEs, wherein the communications include an LTE CRS and an NR PDCCH, and the LTE CRS and the NR PDCCH are sent using one of puncturing signaling, superposition signaling, or drop signaling, wherein the LTE CRS is sent in the same OFDM symbol and the same frequency domain resource element as the NR PDCCH, and (2) a UE among the one or more UEs capable of transceiving the communications with the network node, wherein the UE sends a capability parameter to the network node, the UE receives a puncturing threshold from the network node, and the UE uses the puncturing threshold to process the LTE CRS and decode the NR PDCCH.

[0064] Each of the aspects described in Aspects A, B, C, and D above may be combined with one or more of the following additional elements. Element 1: wherein, when the NR PDCCH overlaps with the LTE CRS and the device does not support puncturing signaling, the device performs NR PDCCH skipping for the NR PDCCH for which the AL is indicated to use puncturing signaling. Element 2: before receiving one or more of the LTE CRS or the NR PDCCH, a capability parameter is sent to a network node, wherein the capability parameter includes one or more parameters for decoding the signal using a relative power level. Element 3: before receiving the NR PDCCH, a puncturing threshold is received, wherein the NR PDCCH relative power level indicates that the NR PDCCH is at a higher power level than the LTE CRS, at a lower power level than the LTE CRS, or at a power level equal to the power level of the LTE CRS, and the NR PDCCH relative power level is used to decode the NRPDCCH. Element 4: wherein the NR PDCCH relative power level is within a specified dB range. Element 5: wherein the puncturing threshold utilizes the NR PDCCH relative power level and superimposed signaling, wherein the AL is equal to or less than the puncturing threshold. Element 6: wherein the puncturing threshold indicates puncturing signaling, and the AL is equal to or less than the puncturing threshold, or the puncturing threshold indicates superposition signaling, and the AL is greater than the puncturing threshold, wherein the puncturing threshold is configured by high-layer signaling. Element 7: wherein the puncturing threshold indicates that the NR PDCCH is not received when overlapped by the LTE CRS, and the AL is equal to or less than the puncturing threshold, wherein the device does not support puncturing signaling. Element 8: wherein the puncturing threshold specifies a DMRS to LTE CRS conflict parameter, wherein the DMRS to LTE CRS conflict parameter specifies a range of relative power levels at which the PDCCH DMRS RE conflicts with the LTE CRS. Element 9: receiving a capability parameter of the UE, wherein the capability parameter indicates whether the UE supports puncturing signaling of the LTE CRS with the NR PDCCH. Element 10: wherein the device determines the AL to be used for the NR PDCCH by using the capability parameter. Element 11: wherein the puncturing threshold specifies one of superposition signaling or puncturing signaling of the NR PDCCH with the LTE CRS. Element 12: wherein the power level used by the NR PDCCH is adjusted using one or more of execution parameters determined based on a previous signal received from the UE or a load of the device. Element 13: wherein the NR PDCCH includes a puncturing threshold to be used with the specified NR PDCCH relative power level, wherein the UE uses the puncturing threshold with subsequent NR PDCCH. Element 14: wherein the UE does not utilize blind decoding when one of the following: the UE does not support the puncturing signaling scheme, the UE is not configured to utilize the puncturing signaling scheme, or the NR PDCCH does not utilize the puncturing signaling scheme.Element 15: Specifying an NR PDCCH relative power level in a puncturing threshold, wherein the NR PDCCH relative power level indicates that the NR PDCCH is at a higher power level than an LTE CRS, at a lower power level than an LTE CRS, or at a power level equal to a power level of an LTE CRS, and the UE utilizes the NR PDCCH relative power level to decode the NR PDDCH. Element 16: Decoding the NRPDCCH and LTE CRS at the UE utilizing one or more of: a puncturing threshold received in a previous signal in which the puncturing threshold comprises the NR PDCCH relative power level, puncturing signaling when the AL is equal to or less than the puncturing threshold, or superimposed signaling when the AL is greater than the puncturing threshold. Element 17: wherein the network node is one of: a gNB, UMTS, E-UTRA, eNB, en-gNB, or ng-eNB.

Claims

1. A device comprising: one or more processors; as well as a memory storing instructions and data which, when executed by the one or more processors, cause the apparatus to: receiving one or more of a Long Term Evolution (LTE) Cell Specific Reference Signal (CRS) or a New Radio (NR) Physical Downlink Control Channel (PDCCH) from a network node; and The NR PDCCH is decoded using a puncturing threshold and an aggregation level AL, wherein the puncturing threshold indicates one or more of: puncturing signaling, superposition signaling, or an NR PDCCH relative power level, wherein when the NR PDCCH relative power level is used, the NR PDCCH relative power level is received in a previous signal.

2. The device according to claim 1, wherein: When the NR PDCCH overlaps with the LTE CRS and the device does not support puncturing signaling, the device performs NR PDCCH skipping for the NR PDCCH for which the AL is indicated to use the puncturing signaling.

3. The apparatus according to claim 1, further comprising: prior to receiving one or more of the LTE CRS or the NR PDCCH, sending capability parameters to the network node, wherein the capability parameters include one or more parameters for using relative power levels to decode signals; and The puncturing threshold is received before receiving the NR PDCCH, wherein the NR PDCCH relative power level indicates that the NR PDCCH is at a higher power level than the LTE CRS, at a lower power level than the LTE CRS, or at a power level equal to the power level of the LTE CRS, and the NR PDCCH relative power level is used to decode the NR PDCCH.

4. The device according to claim 3, wherein: The NR PDCCH relative power level is in the specified decibel dB range.

5. The device according to claim 3, wherein: The puncturing threshold utilizes the NR PDCCH relative power level and the superimposed signaling, wherein the AL is equal to or less than the puncturing threshold.

6. The device according to claim 1, wherein: The puncturing threshold indicates the puncturing signaling, and the AL is equal to or less than the puncturing threshold, or the puncturing threshold indicates the superposition signaling, and the AL is greater than the puncturing threshold, wherein the puncturing threshold is configured by high-layer signaling.

7. The device according to claim 1, wherein: The puncturing threshold indicates that the NR PDCCH is not received when overlapped by the LTE CRS, and the AL is equal to or less than the puncturing threshold, wherein the device does not support puncturing signaling.

8. The device according to claim 1, wherein: The puncturing threshold specifies a demodulation reference signal DMRS to LTE CRS conflict parameter, wherein the DMRS to LTE CRS conflict parameter specifies a range of relative power levels at which a PDCCH DMRS resource element RE conflicts with the LTE CRS.

9. An apparatus comprising: one or more processors; as well as a memory storing instructions and data which, when executed by the one or more processors, cause the apparatus to: determining a puncturing threshold for a New Radio NR Physical Downlink Control Channel PDCCH to a User Equipment UE, wherein the puncturing threshold comprises an aggregation level AL for the NR PDCCH when the apparatus is scheduled to send a Long Term Evolution LTE cell-specific reference signal CRS in the same orthogonal frequency division multiplexing OFDM symbol and the same frequency domain resource element as the NR PDCCH; and The NR PDCCH is sent to the UE, wherein the NR PDCCH is constructed using the puncturing threshold.

10. The apparatus according to claim 9, further comprising: Receive a capability parameter of the UE, wherein the capability parameter indicates whether the UE supports puncturing signaling of the LTE CRS and the NR PDCCH.

11. The device according to claim 10, wherein: The device determines an AL to be used for the NR PDCCH by using the capability parameter.

12. The device according to claim 9, wherein: The puncturing threshold specifies one of superimposed signaling or puncturing signaling of the NR PDCCH and the LTE CRS.

13. The device according to claim 9, wherein: A power level used by the NR PDCCH is adjusted using one or more of a load of the device or an implementation parameter determined based on a previous signal received from the UE.

14. The device according to claim 9, wherein: The NR PDCCH includes a puncturing threshold to be used with the specified NR PDCCH relative power level, wherein the UE uses the puncturing threshold with a subsequent NR PDCCH.

15. A method comprising: Receiving a capability parameter of a user equipment UE, wherein the capability parameter indicates whether the UE supports puncturing signaling of a long term evolution LTE cell-specific reference signal CRS and a new radio NR physical downlink control channel PDCCH; determining a puncturing threshold of the NR PDCCH using the capability parameter, wherein the puncturing threshold comprises an aggregation level AL for the PDCCH, and the LTE CRS is scheduled to be transmitted in the same orthogonal frequency division multiplexing OFDM symbol and the same frequency domain resource element as the NR PDCCH; Using the puncturing threshold, transmitting one or more of the LTE CRS and the NR PDCCH to the UE; and The LTE CRS or the NR PDCCH is received at the UE.

16. The method according to claim 15, wherein: The UE does not utilize blind decoding when one of the following occurs: the UE does not support the puncturing signaling scheme, the UE is not configured to utilize the puncturing signaling scheme, or the NR PDCCH does not use the puncturing signaling scheme.

17. The method according to claim 15, The NR PDCCH relative power level is specified in the puncturing threshold, wherein: The NR PDCCH relative power level indicates that the NR PDCCH is at a higher power level than the LTE CRS, at a lower power level than the LTE CRS, or at a power level equal to the power level of the LTE CRS, and the UE utilizes the NR PDCCH relative power level to decode the NR PDDCH.

18. The method according to claim 15, The NR PDCCH and the LTE CRS are decoded at the UE using one or more of the following: a puncturing threshold received in a previous signal wherein the puncturing threshold includes a puncturing threshold when the AL is equal to or less than the puncturing threshold, or superimposed signaling when the AL is greater than the puncturing threshold.

19. A communication system comprising: A network node capable of transceiving communications with one or more user equipments UE, wherein the communications include a Long Term Evolution LTE Cell Specific Reference Signal CRS and a New Radio NR Physical Downlink Control Channel PDCCH, and the LTE CRS and NR PDCCH are transmitted using one of puncturing signaling, superposition signaling, or dropping signaling, wherein the LTE CRS is transmitted in the same orthogonal frequency division multiplexing OFDM symbol and the same frequency domain resource element as the NR PDCCH; and A UE among the one or more UEs is capable of sending and receiving communications with the network node, wherein the UE sends a capability parameter to the network node, the UE receives a puncturing threshold from the network node, and the UE uses the puncturing threshold to process the LTE CRS and decode the NR PDCCH.

20. The communication system according to claim 19, wherein: The network node is one of: a 5G base station (gNB), an evolved universal mobile telecommunications system (UMTS), terrestrial radio access (E-UTRA), an enhanced 4G eNodeB E-UTRA base station (eNB), an enhanced gNB (en-gNB), or a next generation eNB (ng-eNB).

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