Preventing User Equipment that does not support Cell-Specific Reference Signal (CRS) Muting from Camping on CRS-Muted Carriers

Abstract

To prevent user equipment that does not support cell-specific reference signal muting from camping on CRS muted carriers.SOLUTION: In some aspects, a user equipment piece (UE) may perform the steps of: receiving a first information element (IE) and a second IE, where the first IE indicates whether all UEs that do not support cell-specific reference signal (CRS) muting are barred from a carrier and the second IE indicates whether all UEs that support CRS muting are barred from the carrier; and selectively accessing the carrier based at least in part on at least one of the first IE and the second IE. In some aspects, a UE may determine whether the UE supports cell-specific reference signal (CRS) muting; and may transmit to a base station a capability report that indicates whether the UE supports CRS muting.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS UNDER 35 U.S.C. ...119 This application claims priority to U.S. Provisional Patent Application No. 62 / 668,100, filed May 7, 2018, entitled "TECHNIQUES AND APPARATUSES FOR PREVENTING USER EQUIPMENT THAT DOES NOT SUPPORT CELL-SPECIFIC REFERENCE SIGNAL (CRS) MUTING FROM CAMPING ON CRS MUTED CARRIERS," and U.S. Non-Provisional Patent Application No. 16 / 390,420, filed April 22, 2019, entitled "PREVENTING USER EQUIPMENT THAT DOES NOT SUPPORT CELL-SPECIFIC REFERENCE SIGNAL (CRS) MUTING FROM CAMPING ON CRS MUTED CARRIERS," which are expressly incorporated herein by reference.

[0002] Aspects of the present disclosure generally relate to wireless communications and techniques and apparatus for preventing user equipment that does not support cell-specific reference signal (CRS) muting from camping on a CRS-muted carrier. [Background technology]

[0003] Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, and broadcasts. A typical wireless communication system may employ multiple-access technologies capable of supporting communication with multiple users by sharing available system resources (e.g., bandwidth, transmit power, etc.). 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, single-carrier frequency division multiple access (SC-FDMA) systems, time division synchronous code division multiple access (TD-SCDMA) systems, and Long Term Evolution (LTE). LTE / LTE-Advanced is a set of extensions to the Universal Mobile Telecommunications System (UMTS) mobile standard promulgated by the 3rd Generation Partnership Project (3GPP®).

[0004] A wireless communication network may include several base stations (BSs) that can support communication for several user equipments (UEs). The user equipments (UEs) may communicate with the base stations (BSs) via downlinks and uplinks. The downlink (or forward link) refers to the communication link from the BSs to the UEs, and the uplink (or reverse link) refers to the communication link from the UEs to the BSs. As described in more detail herein, a BS may be referred to as a Node B, gNB, access point (AP), radio head, transmit / receive point (TRP), New Radio (NR) BS, 5G Node B, etc.

[0005] The above multiple access technologies have been adopted in various telecommunications standards to provide common protocols that enable various user equipment to communicate at city, national, regional, and even global levels. New Radio (NR), sometimes referred to as 5G, is a set of extensions to the LTE mobile standard promulgated by the Third Generation Partnership Project (3GPP). NR is designed to improve spectral efficiency, lower costs, improve service, utilize new spectrum, and better support mobile broadband Internet access by using Orthogonal Frequency Division Multiplexing (OFDM) with Cyclic Prefix (CP) (CP-OFDM) on the downlink (DL) and CP-OFDM and / or SC-FDM (e.g., also known as Discrete Fourier Transform Spread OFDM (DFT-s-OFDM)) on the uplink (UL) to better integrate with other open standards, as well as support beamforming, multiple-input multiple-output (MIMO) antenna technology, and carrier aggregation. However, as demand for mobile broadband access continues to grow, further improvements to LTE and NR technologies are needed, and preferably, these improvements should be applicable to other multiple access technologies and telecommunications standards that employ these technologies. Summary of the Invention [Means for solving the problem]

[0006] In some aspects, a method of wireless communication performed by a base station may include determining whether a carrier associated with the base station uses cell-specific reference signal (CRS) muting; determining a master information block (MIB) scrambling sequence or a physical broadcast channel (PBCH) scrambling sequence to be used to scramble a MIB or a PBCH of the carrier based at least in part on whether the carrier uses CRS muting; and transmitting the MIB or the PBCH, wherein the MIB or the PBCH is scrambled using the determined MIB scrambling sequence or the determined PBCH scrambling sequence.

[0007] In some aspects, a base station for wireless communication may include a memory and one or more processors, the processor being configured to determine whether a carrier associated with the base station uses cell-specific reference signal (CRS) muting, determine a master information block (MIB) scrambling sequence or a physical broadcast channel (PBCH) scrambling sequence to be used to scramble a MIB or a PBCH of the carrier based at least in part on whether the carrier uses CRS muting, and transmit the MIB or the PBCH, wherein the MIB or the PBCH is scrambled using the determined MIB scrambling sequence or the determined PBCH scrambling sequence.

[0008] In some aspects, a non-transitory computer-readable medium may store one or more instructions for wireless communications. The one or more instructions, when executed by one or more processors of a base station, may cause the one or more processors to determine whether a carrier associated with the base station uses cell-specific reference signal (CRS) muting, determine a master information block (MIB) scrambling sequence or a physical broadcast channel (PBCH) scrambling sequence to be used to scramble a MIB or a PBCH of the carrier based at least in part on whether the carrier uses CRS muting, and transmit the MIB or the PBCH, wherein the MIB or the PBCH is scrambled using the determined MIB scrambling sequence or the determined PBCH scrambling sequence.

[0009] In some aspects, an apparatus for wireless communication may include means for determining whether a carrier associated with the apparatus uses cell-specific reference signal (CRS) muting; means for determining a master information block (MIB) scrambling sequence or a physical broadcast channel (PBCH) scrambling sequence to be used to scramble a MIB or a PBCH of the carrier based at least in part on whether the carrier uses CRS muting; and means for transmitting the MIB or the PBCH, wherein the MIB or the PBCH is scrambled using the determined MIB scrambling sequence or the determined PBCH scrambling sequence.

[0010] In some aspects, a method of wireless communication performed by a UE may include receiving a Master Information Block (MIB) or a Physical Broadcast Channel (PBCH); determining that descrambling the MIB or PBCH based at least in part on a first scrambling sequence results in an error; and descrambling the MIB or PBCH based at least in part on a second scrambling sequence based at least in part on determining that descrambling the MIB or PBCH based at least in part on the first scrambling sequence results in an error.

[0011] In some aspects, a UE for wireless communication may include a memory and one or more processors, where the processor is configured to receive a Master Information Block (MIB) or a Physical Broadcast Channel (PBCH), determine that descrambling the MIB or PBCH based at least in part on a first scrambling sequence will result in an error, and descramble the MIB or PBCH based at least in part on a second scrambling sequence based at least in part on determining that descrambling the MIB or PBCH based at least in part on the first scrambling sequence will result in an error.

[0012] In some aspects, a non-transitory computer-readable medium may store one or more instructions for wireless communication. The one or more instructions, when executed by one or more processors of a UE, may cause the one or more processors to receive a Master Information Block (MIB) or a Physical Broadcast Channel (PBCH), determine that descrambling the MIB or the PBCH based at least in part on a first scrambling sequence results in an error, and descramble the MIB or the PBCH based at least in part on a second scrambling sequence based at least in part on determining that descrambling the MIB or the PBCH based at least in part on the first scrambling sequence results in an error.

[0013] In some aspects, an apparatus for wireless communication may include means for receiving a Master Information Block (MIB) or a Physical Broadcast Channel (PBCH); means for determining that descrambling the MIB or the PBCH based at least in part on a first scrambling sequence results in an error; and means for descrambling the MIB or the PBCH based at least in part on a second scrambling sequence based at least in part on determining that descrambling the MIB or the PBCH based at least in part on the first scrambling sequence results in an error.

[0014] In some aspects, a method of wireless communication performed by a base station may include determining whether a carrier associated with the base station uses cell-specific reference signal (CRS) muting; determining a first symbol to be used for transmitting a primary synchronization signal (PSS) and a second symbol to be used for transmitting a secondary synchronization signal (SSS) based at least in part on whether the carrier uses CRS muting; and transmitting the PSS in the first symbol and the SSS in the second symbol.

[0015] In some aspects, a base station for wireless communication may include a memory and one or more processors, where the processor is configured to determine whether a carrier associated with the base station uses cell-specific reference signal (CRS) muting, determine a first symbol to be used to transmit a primary synchronization signal (PSS) and a second symbol to be used to transmit a secondary synchronization signal (SSS) based at least in part on whether the carrier uses CRS muting, and transmit the PSS in the first symbol and the SSS in the second symbol.

[0016] In some aspects, a non-transitory computer-readable medium may store one or more instructions for wireless communications. The one or more instructions, when executed by one or more processors of a base station, may cause the one or more processors to determine whether a carrier associated with the base station uses cell-specific reference signal (CRS) muting, determine a first symbol to be used to transmit a primary synchronization signal (PSS) and a second symbol to be used to transmit a secondary synchronization signal (SSS) based at least in part on whether the carrier uses CRS muting, and transmit the PSS in the first symbol and the SSS in the second symbol.

[0017] In some aspects, an apparatus for wireless communication may include means for determining whether a carrier associated with the apparatus uses cell-specific reference signal (CRS) muting; means for determining a first symbol to be used to transmit a primary synchronization signal (PSS) and a second symbol to be used to transmit a secondary synchronization signal (SSS) based at least in part on whether the carrier uses CRS muting; and means for transmitting the PSS in the first symbol and the SSS in the second symbol.

[0018] In some aspects, a method of wireless communication performed by a UE may include determining that a primary synchronization signal (PSS) or a secondary synchronization signal (SSS) is not present in a corresponding first symbol or second symbol, and monitoring a third symbol for a PSS and a fourth symbol for an SSS based at least in part on determining that a PSS or an SSS is not present in the corresponding first symbol or second symbol, wherein the third symbol has a different symbol position within the resource block than the first symbol and the fourth symbol has a different symbol position within the resource block than the second symbol.

[0019] In some aspects, a UE for wireless communication may include a memory and one or more processors, the processor being configured to determine that a primary synchronization signal (PSS) or a secondary synchronization signal (SSS) is not present in a corresponding first symbol or second symbol, and monitor a third symbol for a PSS and a fourth symbol for an SSS based at least in part on determining that a PSS or an SSS is not present in the corresponding first symbol or second symbol, the third symbol having a different symbol position within the resource block than the first symbol, and the fourth symbol having a different symbol position within the resource block than the second symbol.

[0020] In some aspects, a non-transitory computer-readable medium may store one or more instructions for wireless communication. The one or more instructions, when executed by one or more processors of a UE, may cause the one or more processors to determine that a primary synchronization signal (PSS) or a secondary synchronization signal (SSS) is not present in a corresponding first symbol or second symbol, and monitor a third symbol for a PSS and a fourth symbol for an SSS based at least in part on determining that a PSS or SSS is not present in the corresponding first symbol or second symbol, where the third symbol has a different symbol position within the resource block than the first symbol and the fourth symbol has a different symbol position within the resource block than the second symbol.

[0021] In some aspects, an apparatus for wireless communication may include means for determining that a primary synchronization signal (PSS) or a secondary synchronization signal (SSS) is not present in a corresponding first symbol or second symbol; and means for monitoring a third symbol for a PSS and a fourth symbol for an SSS based at least in part on determining that a PSS or SSS is not present in the corresponding first symbol or second symbol, wherein the third symbol has a different symbol position within the resource block than the first symbol and the fourth symbol has a different symbol position within the resource block than the second symbol.

[0022] In some aspects, a method of wireless communication performed by a base station may include determining whether a carrier associated with the base station uses cell-specific reference signal (CRS) muting; configuring a first information element (IE) and a second IE based at least in part on determining whether the carrier uses CRS muting, wherein the first IE indicates whether all user equipment (UE) that does not support CRS muting are barred from the carrier, and the second IE indicates whether all UEs that support CRS muting are barred from the carrier; and transmitting the first IE and the second IE to the UE.

[0023] In some aspects, a base station for wireless communication may include a memory and one or more processors, the processor being configured to: determine whether a carrier associated with the base station uses cell-specific reference signal (CRS) muting; configure a first information element (IE) and a second IE based at least in part on determining whether the carrier uses CRS muting, wherein the first IE indicates whether all user equipment (UE) that does not support CRS muting are barred from the carrier, and the second IE indicates whether all UEs that support CRS muting are barred from the carrier; and transmit the first IE and the second IE to the UE.

[0024] In some aspects, a non-transitory computer-readable medium may store one or more instructions for wireless communications. The one or more instructions, when executed by one or more processors of a base station, may cause the one or more processors to determine whether a carrier associated with the base station uses cell-specific reference signal (CRS) muting, configure a first information element (IE) and a second IE based at least in part on determining whether the carrier uses CRS muting, where the first IE indicates whether all user equipment (UE) that does not support CRS muting are barred from the carrier and the second IE indicates whether all UEs that support CRS muting are barred from the carrier, and transmit the first IE and the second IE to the UE.

[0025] In some aspects, an apparatus for wireless communication may include means for determining whether a carrier associated with the apparatus uses cell-specific reference signal (CRS) muting; means for configuring a first information element (IE) and a second IE based at least in part on determining whether the carrier uses CRS muting, wherein the first IE indicates whether all user equipment (UE) that does not support CRS muting are barred from the carrier, and the second IE indicates whether all UEs that support CRS muting are barred from the carrier; and means for transmitting the first IE and the second IE to the UE.

[0026] In some aspects, a method of wireless communication performed by a UE may include receiving a first information element (IE) and a second IE, where the first IE indicates whether all UEs that do not support cell-specific reference signal (CRS) muting are barred from the carrier and the second IE indicates whether all UEs that support CRS muting are barred from the carrier; and selectively accessing the carrier based at least in part on at least one of the first IE or the second IE.

[0027] In some aspects, a UE for wireless communication may include a memory and one or more processors, the processor being configured to receive a first information element (IE) and a second IE, where the first IE indicates whether all UEs that do not support cell-specific reference signal (CRS) muting are barred from the carrier and the second IE indicates whether all UEs that support CRS muting are barred from the carrier; and selectively access the carrier based at least in part on at least one of the first IE or the second IE.

[0028] In some aspects, a non-transitory computer-readable medium may store one or more instructions for wireless communication. The one or more instructions, when executed by one or more processors of a UE, may cause the one or more processors to receive a first information element (IE) and a second IE, where the first IE indicates whether all UEs that do not support cell-specific reference signal (CRS) muting are barred from the carrier and the second IE indicates whether all UEs that support CRS muting are barred from the carrier, and selectively access the carrier based at least in part on at least one of the first IE or the second IE.

[0029] In some aspects, an apparatus for wireless communication may include means for receiving a first information element (IE) and a second IE, wherein the first IE indicates whether all UEs that do not support cell-specific reference signal (CRS) muting are barred from the carrier, and the second IE indicates whether all UEs that support CRS muting are barred from the carrier; and means for selectively accessing the carrier based at least in part on at least one of the first IE or the second IE.

[0030] In some aspects, a method of wireless communication performed by a base station may include receiving an indication of one or more carriers of the neighboring base station using cell-specific reference signal (CRS) muting from a neighboring base station, and transmitting information identifying the one or more carriers of the neighboring base station using CRS muting to a user equipment (UE).

[0031] In some aspects, a base station for wireless communication may include a memory and one or more processors, the processor configured to receive from a neighboring base station an indication of one or more carriers of the neighboring base station that employ cell-specific reference signal (CRS) muting, and to transmit to a user equipment (UE) information identifying the one or more carriers of the neighboring base station that employ CRS muting.

[0032] In some aspects, a non-transitory computer-readable medium may store one or more instructions for wireless communications that, when executed by one or more processors of a base station, may cause the one or more processors to receive, from a neighboring base station, an indication of one or more carriers of the neighboring base station that employ cell-specific reference signal (CRS) muting, and to transmit, to a user equipment (UE), information identifying the one or more carriers of the neighboring base station that employ CRS muting.

[0033] In some aspects, an apparatus for wireless communication may include means for receiving an indication of one or more carriers of the neighboring base station from a neighboring base station using cell-specific reference signal (CRS) muting, and means for transmitting information identifying the one or more carriers of the neighboring base station to a user equipment (UE) using CRS muting.

[0034] In some aspects, a method of wireless communication performed by a UE may include receiving an indication of one or more carriers of a neighboring base station from a serving base station using cell-specific reference signal (CRS) muting, and selectively accessing at least one of the one or more carriers based at least in part on whether the UE supports CRS muting.

[0035] In some aspects, a UE for wireless communication may include one or more processors, the processors configured to receive from a serving base station an indication of one or more carriers of a neighboring base station that employs cell-specific reference signal (CRS) muting, and to selectively access at least one of the one or more carriers based at least in part on whether the UE supports CRS muting.

[0036] In some aspects, a non-transitory computer-readable medium may store one or more instructions for wireless communication that, when executed by one or more processors of a UE, may cause the one or more processors to receive, from a serving base station, an indication of one or more carriers of a neighboring base station that uses cell-specific reference signal (CRS) muting, and selectively access at least one of the one or more carriers based at least in part on whether the UE supports CRS muting.

[0037] In some aspects, an apparatus for wireless communication may include means for receiving an indication of one or more carriers of a neighboring base station from a serving base station, the indication using cell-specific reference signal (CRS) muting, and means for selectively accessing at least one of the one or more carriers based at least in part on whether the apparatus supports CRS muting.

[0038] In some aspects, a method of wireless communication performed by a base station may include receiving a capability report from a user equipment (UE) indicating whether the UE supports cell-specific reference signal (CRS) muting, determining whether the base station supports CRS muting, and selectively paging the UE on a carrier based at least in part on whether the UE supports CRS muting and whether the base station supports CRS muting for that carrier.

[0039] In some aspects, a base station for wireless communication may include a memory and one or more processors, the processor configured to receive a capability report from a user equipment (UE) indicating whether the UE supports cell-specific reference signal (CRS) muting, determine whether the base station supports CRS muting, and, for a carrier, selectively page the UE on that carrier based at least in part on whether the UE supports CRS muting and whether the base station supports CRS muting.

[0040] In some aspects, a non-transitory computer-readable medium may store one or more instructions for wireless communications. The one or more instructions, when executed by one or more processors of a base station, may cause the one or more processors to receive a capability report from a user equipment (UE) indicating whether the UE supports cell-specific reference signal (CRS) muting, determine whether the base station supports CRS muting, and, for a carrier, selectively page the UE on that carrier based at least in part on whether the UE supports CRS muting and whether the base station supports CRS muting.

[0041] In some aspects, an apparatus for wireless communication may include means for receiving a capability report from a user equipment (UE) indicating whether the UE supports cell-specific reference signal (CRS) muting; means for determining whether the apparatus supports CRS muting; and means for, for a carrier, selectively paging the UE on the carrier based at least in part on whether the UE supports CRS muting and whether the apparatus supports CRS muting.

[0042] In some aspects, a method of wireless communication performed by a UE may include determining whether the UE supports cell-specific reference signal (CRS) muting and transmitting a capability report to a base station indicating whether the UE supports CRS muting.

[0043] In some aspects, a UE for wireless communication may include a memory and one or more processors, the processor configured to determine whether the UE supports cell-specific reference signal (CRS) muting and to transmit a capability report to a base station indicating whether the UE supports CRS muting.

[0044] In some aspects, a non-transitory computer-readable medium may store one or more instructions for wireless communication that, when executed by one or more processors of a UE, may cause the one or more processors to determine whether the UE supports cell-specific reference signal (CRS) muting and to transmit a capability report to a base station indicating whether the UE supports CRS muting.

[0045] In some aspects, an apparatus for wireless communication may include means for determining whether the apparatus supports cell-specific reference signal (CRS) muting and means for transmitting a capability report to a base station indicating whether the UE supports CRS muting.

[0046] Aspects generally include methods, apparatus, systems, computer program products, non-transitory computer-readable media, user equipment, base stations, wireless communication devices, and processing systems, as fully described herein with reference to and as illustrated by the accompanying drawings and this specification.

[0047] The foregoing has outlined rather broadly the features and technical advantages of examples according to the present disclosure in order that the detailed description that follows may be better understood. Additional features and advantages are described below. The concepts and examples disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present disclosure. Such equivalent constructions do not depart from the scope of the appended claims. The nature of the concepts disclosed herein, both their organization and method of operation, together with associated advantages, will be better understood from the following description when considered in connection with the accompanying figures. Each of the figures is provided for the purpose of illustration and description, and not as a definition of the limits of the claims.

[0048] So that the above-mentioned features of the present disclosure may be understood in detail, a more detailed description briefly summarized above may be had by reference to embodiments, some of which are illustrated in the accompanying drawings. It should be noted, however, that the present description may lead to other equally effective embodiments, and that the accompanying drawings illustrate only some typical embodiments of the present disclosure and therefore should not be considered as limiting the scope of the present disclosure. The same reference numbers in different drawings may identify the same or similar elements. [Brief explanation of the drawings]

[0049] [Figure 1] FIG. 1 is a block diagram conceptually illustrating an example of a wireless communication network, in accordance with various aspects of the present disclosure. [Figure 2] FIG. 1 is a block diagram conceptually illustrating an example of a base station communicating with a user equipment (UE) in a wireless communication network, in accordance with various aspects of the present disclosure. [Figure 3A] FIG. 1 is a block diagram conceptually illustrating an example of a frame structure in a wireless communication network, in accordance with various aspects of the present disclosure. [Figure 3B] FIG. 1 is a block diagram conceptually illustrating an example synchronous communication hierarchy in a wireless communication network, in accordance with various aspects of the present disclosure. [Figure 4] FIG. 1 is a block diagram conceptually illustrating an example slot format with a normal cyclic prefix, in accordance with various aspects of the present disclosure. [Figure 5] FIG. 10 illustrates an example related to preventing UEs that do not support CRS muting from camping on a CRS-muted carrier, in accordance with various aspects of the present disclosure. [Figure 6] FIG. 10 illustrates an example related to preventing UEs that do not support CRS muting from camping on a CRS-muted carrier, in accordance with various aspects of the present disclosure. [Figure 7]FIG. 10 illustrates an example related to preventing UEs that do not support CRS muting from camping on a CRS-muted carrier, in accordance with various aspects of the present disclosure. [Figure 8] FIG. 10 illustrates an example related to preventing UEs that do not support CRS muting from camping on a CRS-muted carrier, in accordance with various aspects of the present disclosure. [Figure 9] FIG. 10 illustrates an example related to preventing UEs that do not support CRS muting from camping on a CRS-muted carrier, in accordance with various aspects of the present disclosure. [Figure 10] FIG. 10 illustrates an example related to preventing UEs that do not support CRS muting from camping on a CRS-muted carrier, in accordance with various aspects of the present disclosure. [Figure 11] FIG. 1 illustrates an example process involved in preventing UEs that do not support CRS muting from camping on a CRS-muted carrier, in accordance with various aspects of the present disclosure. [Figure 12] FIG. 1 illustrates an example process involved in preventing UEs that do not support CRS muting from camping on a CRS-muted carrier, in accordance with various aspects of the present disclosure. [Figure 13] FIG. 1 illustrates an example process involved in preventing UEs that do not support CRS muting from camping on a CRS-muted carrier, in accordance with various aspects of the present disclosure. [Figure 14] FIG. 1 illustrates an example process involved in preventing UEs that do not support CRS muting from camping on a CRS-muted carrier, in accordance with various aspects of the present disclosure. [Figure 15] FIG. 1 illustrates an example process involved in preventing UEs that do not support CRS muting from camping on a CRS-muted carrier, in accordance with various aspects of the present disclosure. [Figure 16]FIG. 1 illustrates an example process involved in preventing UEs that do not support CRS muting from camping on a CRS-muted carrier, in accordance with various aspects of the present disclosure. [Figure 17] FIG. 1 illustrates an example process involved in preventing UEs that do not support CRS muting from camping on a CRS-muted carrier, in accordance with various aspects of the present disclosure. [Figure 18] FIG. 1 illustrates an example process involved in preventing UEs that do not support CRS muting from camping on a CRS-muted carrier, in accordance with various aspects of the present disclosure. [Figure 19] FIG. 1 illustrates an example process involved in preventing UEs that do not support CRS muting from camping on a CRS-muted carrier, in accordance with various aspects of the present disclosure. [Figure 20] FIG. 1 illustrates an example process involved in preventing UEs that do not support CRS muting from camping on a CRS-muted carrier, in accordance with various aspects of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0050] In some radio access technologies, such as LTE, a cell-specific reference signal (CRS) may be broadcast periodically by a base station, such as in every subframe (e.g., every 1 ms). For example, the CRS may be a pilot signal inserted in a downlink signal. The CRS may be broadcast across all resource blocks (RBs) at all carrier frequencies and may be used by UEs for timing and frequency synchronization, for radio resource management (RRM) measurements (e.g., RSRP measurements, RSRQ measurements, SINR measurements, etc.), for time-domain and frequency-domain channel estimation, for coherent demodulation, for channel state information (CSI) measurements (e.g., channel quality indicator (CQI) measurements, precoding matrix indicator (PMI) measurements, rank indicator (RI) measurements, etc.), etc.

[0051] This periodic broadcasting of the CRS across all RBs by the base station may cause interference to neighboring base stations and may adversely affect neighboring cell UE demodulation performance, neighboring cell capacity, RRM measurements in neighboring cells, CSI measurements in neighboring cells, etc. Furthermore, broadcasting the CRS across all RBs may consume significant network resource overhead. To mitigate these issues, CRS muting may be used. With CRS muting, the CRS may be broadcast only in the center six physical resource blocks (PRBs) of the carrier bandwidth rather than across all PRBs of the carrier, and the CRS may be muted (e.g., not transmitted) outside the center six PRBs of the carrier. Additionally or alternatively, with CRS muting, the CRS may be transmitted in all PRBs of the carrier as needed for paging, system information acquisition, resource allocation, etc., during the UE's active discontinuous reception (DRX) period, such as for PDSCH scheduling.

[0052] Although CRS muting may improve performance for UEs that support CRS muting (e.g., that can be configured to monitor only the center six PRBs of a carrier for CRS rather than all PRBs of the carrier, and / or that can be activated or deactivated to monitor all PRBs for CRS as needed), some UEs (e.g., legacy UEs) may not support CRS muting. For example, these legacy UEs may be configured to monitor all PRBs of a carrier for CRS. Additionally or alternatively, these legacy UEs may not be able to be configured to monitor only the center six PRBs and, in some cases, all PRBs of a carrier as needed. As a result, these legacy UEs may not be able to demodulate and / or decode communications received on a carrier that uses CRS muting. Some techniques and apparatus described herein prevent this adverse effect on legacy UEs by preventing such legacy UEs that do not support CRS muting from camping on a carrier that uses CRS muting. This may improve network operation and may conserve UE resources (e.g., battery power, processing resources, memory resources, etc.) that would otherwise be wasted by unnecessarily monitoring carriers and / or unnecessarily camping on carriers, etc. Additional details are described below.

[0053] Various aspects of the present disclosure are described more fully below with reference to the accompanying drawings. However, the present disclosure may be embodied in many different forms and should not be construed as limited to any specific structure or function presented throughout this disclosure. Rather, these aspects are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. Based on the teachings herein, those skilled in the art will appreciate that the scope of the present disclosure encompasses any aspect of the present disclosure disclosed herein, whether implemented independently or in combination with any other aspect of the present disclosure. For example, an apparatus may be implemented or a method may be practiced using any number of the aspects described herein. Additionally, the scope of the present disclosure encompasses such apparatuses or methods practiced using other structure, functions, or structure and functions in addition to or other than the various aspects of the disclosure described herein. It should be understood that any aspect of the present disclosure disclosed herein may be embodied by one or more elements of a claim.

[0054] Several aspects of telecommunications systems are now presented with reference to various apparatus and techniques. These apparatus and techniques are described in the following detailed description and illustrated in the accompanying drawings by various blocks, modules, components, circuits, steps, processes, algorithms, etc. (collectively referred to as "elements"). These elements may be implemented using hardware, software, or a combination thereof. Whether such elements are implemented as hardware or software depends on the particular application and design constraints imposed on the overall system.

[0055] It should be noted that although aspects may be described herein using terminology commonly associated with 3G and / or 4G wireless technology, aspects of the present disclosure may be applied in other generation-based communication systems, such as 5G and beyond, including NR technology.

[0056] 1 illustrates a network 100 in which aspects of the present disclosure may be practiced. Network 100 may be an LTE network or some other wireless network, such as a 5G or NR network. Wireless network 100 may include several BSs 110 (denoted as BS 110a, BS 110b, BS 110c, and BS 110d) and other network entities. A BS is an entity that communicates with user equipment (UE) and may also be referred to as a base station, NR BS, Node B, gNB, 5G Node B (NB), access point, transmit / receive point (TRP), etc. Each BS may provide communication coverage for a particular geographic area. In 3GPP, the term "cell" can refer to the coverage area of ​​a BS and / or the BS subsystem serving this coverage area, depending on the context in which the term is used.

[0057] A BS may provide communication coverage for a macrocell, a picocell, a femtocell, and / or another type of cell. A macrocell may cover a relatively large geographic area (e.g., a few kilometers in radius) and may allow unrestricted access by UEs with service subscriptions. A picocell may cover a relatively small geographic area and may allow unrestricted access by UEs with service subscriptions. A femtocell may cover a relatively small geographic area (e.g., a home) and may allow restricted access by UEs that have an association with the femtocell (e.g., UEs in a Closed Subscriber Group (CSG)). A BS for a macrocell may be referred to as a macro BS. A BS for a picocell may be referred to as a pico BS. A BS for a femtocell may be referred to as a femto BS or a home BS. 1, BS 110a may be a macro BS for a macro cell 102a, BS 110b may be a pico BS for a pico cell 102b, and BS 110c may be a femto BS for a femto cell 102c. A BS may support one or multiple (e.g., three) cells. The terms “eNB,” “base station,” “NR BS,” “gNB,” “TRP,” “AP,” “Node B,” “5G NB,” and “cell” may be used interchangeably herein.

[0058] In some examples, the cells may not necessarily be fixed, and the geographic area of ​​the cells may move according to the location of the mobile BS. In some examples, the BSs may be interconnected to each other and / or to one or more other BSs or network nodes (not shown) in the access network 100 through various types of backhaul interfaces, such as direct physical connections, virtual networks, etc., using any suitable transport network.

[0059] Wireless network 100 may also include relay stations. A relay station is an entity that can receive data transmissions from an upstream station (e.g., a BS or UE) and send the data transmissions to a downstream station (e.g., a UE or BS). A relay station may also be a UE that can relay transmissions for other UEs. In the example shown in FIG. 1, relay station 110d may communicate with macro BS 110a and UE 120d to facilitate communication between BS 110a and UE 120d. A relay station may also be called a relay BS, a relay base station, a relay, etc.

[0060] Wireless network 100 may be a heterogeneous network including different types of BSs, e.g., macro BSs, pico BSs, femto BSs, relay BSs, etc. These different types of BSs may have different transmit power levels, different coverage areas, and different impacts on interference in wireless network 100. For example, macro BSs may have high transmit power levels (e.g., 5-40 watts), while pico BSs, femto BSs, and relay BSs may have lower transmit power levels (e.g., 0.1-2 watts).

[0061] A network controller 130 may couple to a set of BSs and may provide coordination and control for these BSs. The network controller 130 may communicate with the BSs via a backhaul. The BSs may also communicate with each other directly or indirectly, for example, via wireless or wireline backhaul.

[0062] The UEs 120 (e.g., 120a, 120b, 120c) may be dispersed throughout the wireless network 100, and each UE may be fixed or mobile. A UE may also be referred to as an access terminal, terminal, mobile station, subscriber unit, station, etc. A UE may be a cellular phone (e.g., a smartphone), a personal digital assistant (PDA), a wireless modem, a wireless communication device, a handheld device, a laptop computer, a cordless phone, a wireless local loop (WLL) station, a tablet, a camera, a gaming device, a netbook, a smartbook, an ultrabook, a medical device or equipment, a biometric sensor / device, a wearable device (smart watch, smart clothing, smart glasses, smart wristband, smart jewelry (e.g., smart ring, smart bracelet)), an entertainment device (e.g., a music or video device, or satellite radio), a vehicle component or sensor, a smart meter / sensor, industrial manufacturing equipment, a global positioning system device, or any other suitable device configured to communicate via a wireless or wired medium.

[0063] Some UEs may be considered machine type communication (MTC) UEs or evolved or enhanced machine type communication (eMTC) UEs. MTC UEs and eMTC UEs include, for example, remote devices such as robots, drones, sensors, meters, monitors, location tags, etc. that may communicate with a base station, another device (e.g., a remote device), or some other entity. A wireless node may provide connectivity for or to a network (e.g., a wide area network such as the Internet or a cellular network), for example, via a wired or wireless communication link. Some UEs may be considered Internet of Things (IoT) devices and / or may be implemented as NB-IoT (narrowband Internet of Things) devices. Some UEs may be considered customer premises equipment (CPE). The UE 120 may be included inside a housing that houses components of the UE 120, such as processor components, memory components, etc.

[0064] Generally, any number of wireless networks may be deployed within a given geographic area. Each wireless network may support a particular RAT and may operate on one or more frequencies. A RAT may also be referred to as a radio technology, air interface, etc. A frequency may also be referred to as a carrier, frequency channel, etc. Each frequency may support a single RAT within a given geographic area to avoid interference between wireless networks of different RATs. In some cases, NR or 5G RAT networks may be deployed.

[0065] In some examples, access to the air interface may be scheduled, and a scheduling entity (e.g., a base station) allocates resources for communication among some or all devices and equipment within the scheduling entity's service area or cell. Within this disclosure, as described further below, the scheduling entity may be responsible for scheduling, assigning, reconfiguring, and releasing resources for one or more subordinate entities. That is, for scheduled communication, the subordinate entities utilize the resources allocated by the scheduling entity.

[0066] A base station is not the only entity that can function as a scheduling entity. That is, in some examples, a UE may function as a scheduling entity that schedules resources for one or more subordinate entities (e.g., one or more other UEs). In this example, the UE is functioning as the scheduling entity, and other UEs utilize the resources scheduled by the UE for wireless communication. A UE may function as a scheduling entity in a peer-to-peer (P2P) network and / or in a mesh network. In a mesh network example, UEs may optionally communicate directly with each other in addition to communicating with the scheduling entity.

[0067] Thus, in wireless communication networks with scheduled access to time-frequency resources and having cellular, P2P, and mesh configurations, a scheduling entity and one or more subordinate entities may communicate utilizing the scheduled resources.

[0068] In some aspects, two or more UEs 120 (e.g., shown as UE 120a and UE 120e) may communicate directly (e.g., without using a base station 110 as an intermediary for communicating with each other) using one or more sidelink channels. For example, the UEs 120 may communicate using peer-to-peer (P2P) communication, device-to-device (D2D) communication, a vehicle-to-everything (V2X) protocol (which may include, e.g., a vehicle-to-vehicle (V2V) protocol, a vehicle-to-infrastructure (V2I) protocol, etc.), a mesh network, etc. In this case, the UEs 120 may perform scheduling operations, resource selection operations, and / or other operations described elsewhere herein as being performed by the base station 110.

[0069] As noted above, Figure 1 is provided as an example only. Other examples are possible and may differ from those described with respect to Figure 1.

[0070] 2 shows a block diagram of a design 200 of a base station 110 and a UE 120, which may be one of the base stations and one of the UEs in FIG. 1. Base station 110 may be equipped with T antennas 234a through 234t, and UE 120 may be equipped with R antennas 252a through 252r, where in general T≧1 and R≧1.

[0071] At the base station 110, the transmit processor 220 may receive data from a data source 212 for one or more UEs, may select one or more modulation and coding schemes (MCSs) for each UE based at least in part on a channel quality indicator (CQI) received from the UE, may process (e.g., encode and modulate) the data for each UE based at least in part on the MCS selected for the UE, and may provide data symbols to all UEs. The transmit processor 220 may also process system information (e.g., for semi-static resource partitioning information (SRPI), etc.) and control information (e.g., CQI requests, grants, upper layer signaling, etc.) and may provide overhead symbols and control symbols. The transmit processor 220 may also generate reference symbols for reference signals (e.g., cell-specific reference signals (CRSs)) and synchronization signals (e.g., primary synchronization signals (PSSs) and secondary synchronization signals (SSSs)). The transmit (TX) multiple-input multiple-output (MIMO) processor 230 may perform spatial processing (e.g., precoding) on ​​the data symbols, control symbols, overhead symbols, and / or reference symbols, if applicable, and may provide T output symbol streams to T modulators (MODs) 232a through 232t. Each modulator 232 may process a respective output symbol stream (e.g., for OFDM, etc.) to obtain an output sample stream. Each modulator 232 may further process (e.g., convert to analog, amplify, filter, and upconvert) the output sample stream to obtain a downlink signal. The T downlink signals from modulators 232a through 232t may be transmitted via T antennas 234a through 234t, respectively. According to various aspects described in more detail below, synchronization signals may be generated using location coding to convey additional information.

[0072] At UE 120, antennas 252a through 252r may receive downlink signals from base station 110 and / or other base stations and may provide received signals to demodulators (DEMODs) 254a through 254r, respectively. Each demodulator 254 may condition (e.g., filter, amplify, downconvert, and digitize) the received signal to obtain input samples. Each demodulator 254 may further process the input samples (e.g., for OFDM, etc.) to obtain received symbols. A MIMO detector 256 may obtain received symbols from all R demodulators 254a through 254r, perform MIMO detection on the received symbols if applicable, and provide detected symbols. A receive processor 258 may process (e.g., demodulate and decode) the detected symbols, provide decoded data for UE 120 to a data sink 260, and provide decoded control and system information to controller / processor 280. The channel processor may determine a reference signal received power (RSRP), a received signal strength indicator (RSSI), a reference signal received quality (RSRQ), a channel quality indicator (CQI), and the like.

[0073] On the uplink, at the UE 120, a transmit processor 264 may receive and process data from a data source 262 and control information (e.g., for reports comprising RSRP, RSSI, RSRQ, CQI, etc.) from a controller / processor 280. The transmit processor 264 may also generate reference symbols for one or more reference signals. The symbols from the transmit processor 264 may be precoded by a TX MIMO processor 266 if applicable, further processed by modulators 254a through 254r (e.g., for DFT-s-OFDM, CP-OFDM, etc.), and transmitted to the base station 110. At the base station 110, uplink signals from the UE 120 and other UEs may be received by the antennas 234, processed by a demodulator 232, detected by a MIMO detector 236 if applicable, and further processed by a receive processor 238 to obtain decoded data and control information sent by the UE 120. The receive processor 238 may provide the decoded data to a data sink 239 and the decoded control information to the controller / processor 240. The base station 110 may include a communication unit 244 and may communicate with the network controller 130 via the communication unit 244. The network controller 130 may include a communication unit 294, a controller / processor 290, and a memory 292.

[0074] In some aspects, one or more components of the UE 120 may be included in a housing. The controller / processor 240 of the base station 110, the controller / processor 280 of the UE 120, and / or any other components of FIG. 2 may perform one or more techniques related to preventing UEs that do not support CRS muting from camping on a CRS-muted carrier, as described in more detail elsewhere herein. 2 may perform or direct the operation of, for example, process 1100 of FIG. 11 , process 1200 of FIG. 12 , process 1300 of FIG. 13 , process 1400 of FIG. 14 , process 1500 of FIG. 15 , process 1600 of FIG. 16 , process 1700 of FIG. 17 , process 1800 of FIG. 18 , process 1900 of FIG. 19 , process 2000 of FIG. 20 , and / or other processes as described herein. Memories 242 and 282 may store data and program codes for base station 110 and UE 120, respectively. Scheduler 246 may schedule UEs for data transmission on the downlink and / or uplink.

[0075] The stored program code, when executed by processor 280 and / or other processors and modules at UE 120, may cause UE 120 to perform operations described with respect to process 1200 of Figure 12, process 1400 of Figure 14, process 1600 of Figure 16, process 1800 of Figure 18, process 2000 of Figure 20, and / or other processes as described herein. The stored program code, when executed by processor 240 and / or other processors and modules at base station 110, may cause base station 110 to perform operations described with respect to process 1100 of Figure 11, process 1300 of Figure 13, process 1500 of Figure 15, process 1700 of Figure 17, process 1900 of Figure 19, and / or other processes as described herein. Scheduler 246 may schedule UEs for data transmission on the downlink and / or uplink.

[0076] In some aspects, the UE 120 may include means for receiving a Master Information Block (MIB) or a Physical Broadcast Channel (PBCH); means for determining that descrambling the MIB or PBCH based at least in part on a first scrambling sequence will result in an error; means for descrambling the MIB or PBCH based at least in part on a second scrambling sequence based at least in part on determining that descrambling the MIB or PBCH based at least in part on the first scrambling sequence will result in an error; and the like. Additionally or alternatively, the UE 120 may include means for determining that a primary synchronization signal (PSS) or a secondary synchronization signal (SSS) is not present in a corresponding first symbol or second symbol, and means for monitoring a third symbol for a PSS and a fourth symbol for a SSS based at least in part on determining that a PSS or SSS is not present in the corresponding first symbol or second symbol, where the third symbol has a different symbol position within the resource block than the first symbol and the fourth symbol has a different symbol position within the resource block than the second symbol.

[0077] Additionally or alternatively, UE 120 may include means for receiving a first information element (IE) and a second IE, where the first IE indicates whether all UEs that do not support cell-specific reference signal (CRS) muting are barred from the carrier and the second IE indicates whether all UEs that support CRS muting are barred from the carrier, and means for selectively accessing a carrier based at least in part on at least one of the first IE or the second IE, etc. Additionally or alternatively, UE 120 may include means for receiving from a serving base station an indication of one or more carriers of a neighboring base station that use cell-specific reference signal (CRS) muting, and means for selectively accessing at least one of the one or more carriers based at least in part on whether UE 120 supports CRS muting, etc. Additionally or alternatively, UE 120 may include means for determining whether the device supports cell-specific reference signal (CRS) muting, means for transmitting a capability report to the base station indicating whether the UE supports CRS muting, etc. In some aspects, such means may include one or more components of the UE 120 described with respect to FIG.

[0078] In some aspects, the base station 110 may include means for determining whether a carrier associated with the base station 110 uses cell-specific reference signal (CRS) muting; means for determining a master information block (MIB) scrambling sequence or a physical broadcast channel (PBCH) scrambling sequence to be used to scramble the carrier's MIB or PBCH based at least in part on whether the carrier uses CRS muting; means for transmitting the MIB or PBCH, and the MIB or PBCH is scrambled using the determined MIB scrambling sequence or the determined PBCH scrambling sequence, and the like. Additionally or alternatively, the base station 110 may include means for determining whether a carrier associated with the base station 110 uses cell-specific reference signal (CRS) muting, means for determining a first symbol to be used to transmit a primary synchronization signal (PSS) and a second symbol to be used to transmit a secondary synchronization signal (SSS) based at least in part on whether the carrier uses CRS muting, means for transmitting the PSS in the first symbol and the SSS in the second symbol, etc.

[0079] Additionally or alternatively, the base station 110 may include means for determining whether a carrier associated with the device uses cell-specific reference signal (CRS) muting, means for configuring a first information element (IE) and a second IE based at least in part on determining whether the carrier uses CRS muting, the first IE indicating whether all user equipment (UE) that does not support CRS muting are barred from the carrier, and the second IE indicating whether all UEs that support CRS muting are barred from the carrier, means for transmitting the first IE and the second IE to the UE, etc. Additionally or alternatively, the base station 110 may include means for receiving from a neighboring base station an indication of one or more carriers of the neighboring base station that use cell-specific reference signal (CRS) muting, means for transmitting to the user equipment (UE) information identifying one or more carriers of the neighboring base station that use CRS muting, etc. Additionally or alternatively, the base station 110 may include means for receiving a capability report from a user equipment (UE) indicating whether the UE supports cell-specific reference signal (CRS) muting, means for determining whether the base station 110 supports CRS muting, means for selectively paging the UE on a carrier based at least in part on whether the UE supports CRS muting and whether the base station 110 supports CRS muting, etc. In some aspects, such means may include one or more components of the base station 110 described with respect to FIG.

[0080] 2 are illustrated as separate components, the functionality described above with respect to the blocks may be implemented with a single hardware component, a software component, or a combination of components, or various combinations of components. For example, the functionality described with respect to the transmit processor 264, the receive processor 258, and / or the TX MIMO processor 266 may be performed by or under the control of the processor 280.

[0081] As noted above, Figure 2 is provided as an example only. Other examples are possible and may differ from those described with respect to Figure 2.

[0082] FIG. 3A shows an example frame structure 300 for FDD in a telecommunications system (e.g., NR). The transmission timeline for each of the downlink and uplink may be partitioned into units of radio frames (sometimes referred to as frames). Each radio frame may have a predetermined duration (e.g., 10 milliseconds (ms)) and may be partitioned into a set of Z subframes (e.g., with indices 0 to Z-1), where Z≧1. Each subframe may have a predetermined duration (e.g., 1 ms) and may include a set of slots (e.g., 2 slots per subframe). m slots are shown in FIG. 3A , where m is the numerology used for transmission, such as 0, 1, 2, 3, 4, etc.). Each slot may include a set of L symbol periods. For example, each slot may include 14 symbol periods (e.g., as shown in FIG. 3A ), 7 symbol periods, or another number of symbol periods. If a subframe includes two slots (e.g., when m=1), the subframe may include 2L symbol periods, where the 2L symbol periods in each subframe may be assigned indices 0 through 2L−1. In some aspects, the scheduling unit for FDD may be frame-based, subframe-based, slot-based, symbol-based, etc.

[0083] Although some techniques are described herein with respect to frames, subframes, slots, etc., these techniques may be equally applicable to other types of wireless communication structures, which may be referred to using terms other than “frame,” “subframe,” “slot,” etc. in 5G NR. In some aspects, a wireless communication structure may refer to a periodic, time-bound communication unit defined by a wireless communication standard and / or protocol. Additionally or alternatively, a different configuration of the wireless communication structure than that shown in FIG. 3A may be used.

[0084] In some telecommunications (e.g., NR), a base station may transmit synchronization signals. For example, a base station may transmit a primary synchronization signal (PSS), a secondary synchronization signal (SSS), etc. on the downlink for each cell supported by the base station. The PSS and SSS may be used by a UE for cell search and acquisition. For example, the PSS may be used by the UE to determine symbol timing, and the SSS may be used by the UE to determine a physical cell identifier associated with the base station and frame timing. The base station may also transmit a physical broadcast channel (PBCH). The PBCH may carry some system information, such as system information to support initial access by the UE.

[0085] In some aspects, the base station may transmit the PSS, SSS, and / or PBCH according to a synchronization communication layer (e.g., a synchronization signal (SS) layer) that includes multiple synchronization communications (e.g., SS blocks), as described below with respect to FIG. 3B.

[0086] FIG. 3B is a block diagram conceptually illustrating an exemplary SS hierarchy, which is an example of a synchronous communication hierarchy. As shown in FIG. 3B, the SS hierarchy may include an SS burst set, which may include multiple SS bursts (identified as SS burst 0 through SS burst B-1, where B is the maximum number of repetitions of an SS burst that may be transmitted by a base station). As further shown, each SS burst may include one or more SS blocks (SS block 0 through SS block B-1). max_SS-1 ), where b max_SS-1 The SS burst set may include a fixed or dynamic length, shown in FIG. 3B as Y milliseconds. In some aspects, the ...

[0087] The SS burst set shown in Figure 3B is an example of a synchronous communication set, and other synchronous communication sets may be used in conjunction with the techniques described herein. Additionally, the SS block shown in Figure 3B is an example of a synchronous communication set, and other synchronous communication sets may be used in conjunction with the techniques described herein.

[0088] In some aspects, an SS block includes resources carrying a PSS, SSS, PBCH, and / or other synchronization signals (e.g., a tertiary synchronization signal (TSS)) and / or synchronization channels. In some aspects, multiple SS blocks are included in an SS burst, and the PSS, SSS, and / or PBCH may be the same across each SS block of the SS burst. In some aspects, a single SS block may be included in an SS burst. In some aspects, an SS block may be at least four symbol periods in length, where each symbol carries one or more of a PSS (e.g., occupying one symbol), an SSS (e.g., occupying one symbol), and / or a PBCH (e.g., occupying two symbols).

[0089] In some aspects, the symbols of an SS block are contiguous, as shown in FIG. 3B. In some aspects, the symbols of an SS block are not contiguous. Similarly, in some aspects, one or more SS blocks of an SS burst may be transmitted in contiguous radio resources (e.g., contiguous symbol periods) during one or more slots. Additionally or alternatively, one or more SS blocks of an SS burst may be transmitted in non-contiguous radio resources.

[0090] In some aspects, an SS burst may have a burst duration, whereby an SS block of an SS burst is transmitted by a base station according to the burst duration. In other words, an SS block may be repeated during each SS burst. In some aspects, an SS burst set may have a burst set periodicity, whereby an SS burst of an SS burst set is transmitted by a base station according to a fixed burst set periodicity. In other words, an SS burst may be repeated during each SS burst set.

[0091] A base station may transmit system information, such as a system information block (SIB), on a physical downlink shared channel (PDSCH) in some slots. The base station may transmit control information / data on a physical downlink control channel (PDCCH) in C symbol periods of the slot, where B may be configurable per slot. The base station may transmit traffic data and / or other data on the PDSCH in the remaining symbol periods of each slot.

[0092] As noted above, Figures 3A and 3B are provided as examples. Other examples are possible and may differ from those described with respect to Figures 3A and 3B.

[0093] 4 shows an example slot format 410 with a normal cyclic prefix. Available time-frequency resources may be partitioned into resource blocks. Each resource block may cover a set of subcarriers (e.g., 12 subcarriers) in one slot and may contain several resource elements. Each resource element may cover one subcarrier in one symbol period (e.g., in time) and may be used to send one modulation symbol, which may be real or complex-valued.

[0094] In some telecommunications systems (e.g., NR), an interlace structure may be used for each of the downlink and uplink for FDD. For example, Q interlaces with indices 0 to Q-1 may be defined, where Q may be equal to 4, 6, 8, 10, or some other value. Each interlace may include slots spaced apart by Q frames. In particular, interlace q may include slots q, q+Q, q+2Q, etc., where q∈{0,...,Q-1}.

[0095] A UE may be located within the coverage of multiple BSs. One of these BSs may be selected to serve the UE. The serving BS may be selected based at least in part on various criteria such as received signal strength, received signal quality, path loss, etc. The received signal quality may be quantified by a signal-to-noise-and-interference ratio (SINR) or reference signal received quality (RSRQ) or some other metric. The UE may operate in a dominant interference scenario in which the UE may observe significant interference from one or more interfering BSs.

[0096] Although example aspects described herein may relate to NR or 5G technology, aspects of the present disclosure may be applicable to other wireless communication systems. New Radio (NR) may refer to a radio configured to operate according to a new air interface (e.g., other than an Orthogonal Frequency Division Multiple Access (OFDMA)-based air interface) or a fixed transport layer (e.g., other than Internet Protocol (IP)). In aspects, NR may utilize OFDM with CP (referred to herein as Cyclic Prefix OFDM or CP-OFDM) and / or SC-FDM on the uplink, CP-OFDM on the downlink, and may include support for half-duplex operation using TDD. In aspects, NR may utilize, for example, OFDM with CP (referred to herein as CP-OFDM) and / or Discrete Fourier Transform Spread Orthogonal Frequency Division Multiplexing (DFT-s-OFDM) on the uplink, CP-OFDM on the downlink, and may include support for half-duplex operation using TDD. NR may include enhanced mobile broadband (eMBB) services targeting wide bandwidths (e.g., 80 megahertz (MHz) or greater), millimeter wave (mmW) targeting high carrier frequencies (e.g., 60 gigahertz (GHz)), massive MTC (mMTC) targeting non-backward compatible MTC techniques, and / or mission critical targeting ultra-reliable low latency communications (URLLC) services.

[0097] In some aspects, a single component carrier bandwidth of 100 MHz may be supported. An NR resource block may span 12 subcarriers with a subcarrier bandwidth of 60 or 120 kilohertz (kHz) for a duration of 0.1 milliseconds (ms). Each radio frame may include 40 slots and may be 10 ms long. Thus, each slot may be 0.25 ms long. Each slot may indicate a link direction (e.g., DL or UL) for data transmission, and the link direction per slot may be dynamically switched. Each slot may contain DL / UL data as well as DL / UL control data.

[0098] Beamforming may be supported, and beam directions may be dynamically configured. MIMO transmission with precoding may also be supported. MIMO configuration in DL may support up to eight transmit antennas with multi-layer DL transmission of up to eight streams and up to two streams per UE. Multi-layer transmission with up to two streams per UE may be supported. Aggregation of multiple cells may be supported with up to eight serving cells. Alternatively, NR may support different air interfaces other than OFDM-based interfaces. The NR network may include entities such as a central unit or distributed units.

[0099] As noted above, Figure 4 is provided as an example. Other examples are possible and may differ from those described with respect to Figure 4.

[0100] In some radio access technologies, such as LTE, a cell-specific reference signal (CRS) may be broadcast periodically by a base station, such as in every subframe (e.g., every 1 ms). For example, the CRS may be a pilot signal inserted in a downlink signal. The CRS may be broadcast across all resource blocks (RBs) at all carrier frequencies and may be used by UEs for timing and frequency synchronization, for radio resource management (RRM) measurements (e.g., RSRP measurements, RSRQ measurements, SINR measurements, etc.), for time-domain and frequency-domain channel estimation, for coherent demodulation, for channel state information (CSI) measurements (e.g., channel quality indicator (CQI) measurements, precoding matrix indicator (PMI) measurements, rank indicator (RI) measurements, etc.), etc.

[0101] This periodic broadcasting of the CRS across all RBs by the base station may cause interference to neighboring base stations and may adversely affect neighboring cell UE demodulation performance, neighboring cell capacity, RRM measurements in neighboring cells, CSI measurements in neighboring cells, etc. Furthermore, broadcasting the CRS across all RBs may consume significant network resource overhead. To mitigate these issues, CRS muting may be used. With CRS muting, the CRS may be broadcast only in the center six physical resource blocks (PRBs) of the carrier bandwidth rather than across all PRBs of the carrier, and the CRS may be muted (e.g., not transmitted) outside the center six PRBs of the carrier. Additionally or alternatively, with CRS muting, the CRS may be transmitted in all PRBs of the carrier as needed for paging, system information acquisition, resource allocation, etc., during the UE's active discontinuous reception (DRX) period, such as for PDSCH scheduling.

[0102] While CRS muting may improve performance for UEs that support CRS muting (e.g., can be configured to monitor only the center six PRBs of a carrier for CRS rather than all PRBs of a carrier, can be activated or deactivated to monitor all PRBs for CRS as needed, can communicate on a carrier that uses CRS muting, etc.), some UEs (e.g., legacy UEs) may not support CRS muting (e.g., may not be able to communicate on a carrier that uses CRS muting). For example, these legacy UEs may be configured to monitor all PRBs of a carrier for CRS. Additionally or alternatively, these legacy UEs may not be able to be configured to monitor only the center six PRBs and, in some cases, all PRBs of a carrier as needed. As a result, these legacy UEs may not be able to demodulate and / or decode communications received on a carrier that uses CRS muting. Some techniques and apparatus described herein prevent this adverse effect on legacy UEs by preventing such legacy UEs that do not support CRS muting from camping on a carrier that uses CRS muting. Additional details are described below.

[0103] FIG. 5 is a diagram illustrating an example 500 relating to preventing UEs that do not support CRS muting from camping on CRS-muted carriers, in accordance with various aspects of the present disclosure.

[0104] As indicated by reference numeral 510, the base station 110 may determine a master information block (MIB) scrambling sequence and / or a physical broadcast channel (PBCH) scrambling sequence to be used to scramble the MIB and / or PBCH of a carrier based at least in part on whether the carrier uses CRS muting. For example, the base station 110 may determine whether the carrier of the base station 110 uses CRS muting. The base station 110 may use a first MIB and / or PBCH scrambling sequence if the carrier does not use CRS muting, or may use a second MIB and / or PBCH scrambling sequence if the carrier uses CRS muting.

[0105] In some aspects, the first MIB and / or PBCH scrambling sequence comprises:

number

number

[0106] In some aspects, the second MIB and / or PBCH scrambling sequence comprises:

number

number

[0107] As indicated by reference numeral 520, the MIB and / or PBCH may be transmitted by base station 110 and received by UE 120 on a carrier. As described above, the MIB and / or PBCH may be scrambled using a determined MIB and / or PBCH scrambling sequence. Thus, the MIB and / or PBCH may be scrambled using different scrambling sequences based at least in part on whether the carrier over which the MIB and / or PBCH is transmitted uses CRS muting.

[0108] As indicated by reference numeral 530, UE 120 may determine that the first scrambling sequence failed to correctly descramble the MIB and / or PBCH and may descramble the MIB and / or PBCH using a second scrambling sequence based at least in part on determining that the first descrambling sequence failed to correctly descramble the MIB and / or PBCH. For example, UE 120 may first attempt to descramble the MIB and / or PBCH using the assumption (e.g., hypothesis) that the first MIB scrambling sequence and / or the first PBCH scrambling sequence described above were used to scramble the MIB and / or PBCH. If such descrambling fails (e.g., results in an error), the UE 120 may attempt to descramble the MIB and / or PBCH using the assumption that the second MIB scrambling sequence and / or the second PBCH scrambling sequence described above were used to scramble the MIB and / or PBCH. In some aspects, the UE 120 may use both scrambling sequences (e.g., the scrambling sequences corresponding to the carriers that support CRS muting) to descramble the MIB and / or PBCH.

number

number

[0109] In some aspects, the UE 120 may descramble the MIB based at least in part on the second scrambling sequence only if the UE 120 supports CRS muting (e.g., only if the UE 120 is capable of communicating on a carrier that uses CRS muting). For example, a UE 120 that supports CRS muting may be configured to perform sequential descrambling as described above, while a UE 120 that does not support CRS muting may be configured to attempt descrambling based at least in part on only the first scrambling sequence and not the second scrambling sequence. In this case, a UE 120 that does not support CRS muting may fail to descramble the MIB of a carrier that supports CRS muting because the MIB uses the second descrambling sequence that is not used by the UE 120 to attempt to descramble the MIB. As a result, a UE 120 that does not support CRS muting may not be able to access (e.g., read its system information, camp on it, etc.) a carrier that does support CRS muting, thereby preventing the adverse effects described elsewhere in this specification.

[0110] As noted above, Figure 5 is provided as an example. Other examples are possible and may differ from those described with respect to Figure 5.

[0111] FIG. 6 is a diagram illustrating another example 600 related to preventing UEs that do not support CRS muting from camping on CRS-muted carriers, in accordance with various aspects of the present disclosure.

[0112] As indicated by reference numeral 610, the base station 110 may determine a symbol in which the PSS is to be transmitted and / or may determine another symbol in which the SSS is to be transmitted based at least in part on whether the carrier uses CRS muting. For example, the base station 110 may determine whether the carrier of the base station 110 uses CRS muting. In some aspects, the base station 110 may use a different symbol for transmission of the PSS if the carrier uses CRS muting versus if the carrier does not use CRS muting. Additionally or alternatively, the base station 110 may use a different symbol for transmission of the SSS if the carrier uses CRS muting versus if the carrier does not use CRS muting.

[0113] For example, as indicated by reference numeral 620, in a frequency division duplex (FDD) configuration, if a carrier does not use CRS muting, the PSS may be transmitted in the last symbol of the slot and the SSS may be transmitted in the penultimate symbol of the slot (e.g., immediately before the symbol carrying the PSS). However, as indicated by reference numeral 630, in an FDD configuration, if a carrier uses CRS muting, the SSS may be transmitted in the last symbol of the slot and the PSS may be transmitted in the penultimate symbol of the slot (e.g., immediately before the symbol carrying the SSS). In some aspects, in an FDD configuration, both the PSS and the SSS may be transmitted in slot 0 (e.g., the first slot) and slot 10 (e.g., the 11th slot) of a frame.

[0114] As another example, in a time division duplex (TDD) configuration, if a carrier does not use CRS muting, the SSS may be transmitted in the last symbol of a slot, and the PSS may be transmitted in the third symbol of the following slot (e.g., immediately after the slot carrying the SSS). In this case, the SSS may be transmitted in subframe 0 and slot 1 of a frame (e.g., the first subframe and second slot), and the PSS may be transmitted in subframe 1 and slot 2 of a frame (e.g., the second subframe and third slot). Furthermore, the SSS may be transmitted in subframe 5 and slot 11 of a frame (e.g., the sixth subframe and twelfth slot), and the PSS may be transmitted in subframe 6 and slot 12 of a frame (e.g., the seventh subframe and thirteenth slot). However, in a TDD configuration, if a carrier uses CRS muting, the PSS may be transmitted in the last symbol of a slot, and the SSS may be transmitted in the third symbol of the following slot (e.g., immediately after the slot carrying the PSS). In this case, the PSS may be transmitted in subframe 0 and slot 1 of the frame (e.g., the first subframe and the second slot), and the SSS may be transmitted in subframe 1 and slot 2 of the frame (e.g., the second subframe and the third slot). Further, the PSS may be transmitted in subframe 5 and slot 11 of the frame (e.g., the sixth subframe and the twelfth slot), and the SSS may be transmitted in subframe 6 and slot 12 of the frame (e.g., the seventh subframe and the thirteenth slot).

[0115] As indicated by reference numeral 640, the base station 110 may transmit and the UE 120 may receive the PSS and SSS in the determined symbols. For example, as described above, the symbols in which the PSS and SSS are transmitted may be swapped when the carrier uses CRS muting relative to when the carrier does not use CRS muting. In this case, as described above, a first symbol configuration may be used for transmitting the PSS and SSS when the carrier does not use CRS muting, and a second symbol configuration may be used for transmitting the PSS and SSS when the carrier uses CRS muting.

[0116] As indicated by reference numeral 650, UE 120 may determine that a PSS and / or SSS were not acquired using a first symbol configuration and may monitor for a PSS and / or SSS using a second symbol configuration based at least in part on determining that a PSS and / or SSS were not acquired using the first symbol configuration. For example, UE 120 may monitor for a PSS in a first symbol and may monitor for an SSS in a second symbol. If this monitoring fails to acquire a PSS and / or SSS (e.g., because a PSS or SSS is not present in the corresponding first or second symbol), UE 120 may monitor for a PSS in a third symbol and / or may monitor for an SSS in a fourth symbol.

[0117] As described above, the first and second symbols may follow a first symbol configuration, and the third and fourth symbols may follow a second symbol configuration. For example, the third symbol may be in a different symbol position than the first symbol (e.g., within an RB, subframe, slot, etc.), and the fourth symbol may be in a different symbol position than the second symbol. If the symbols for PSS and SSS are swapped in the second symbol configuration compared to the first symbol configuration, the third symbol may be in the same symbol position as the second symbol, and the fourth symbol may be in the same symbol position as the first symbol. In this case, UE 120 may monitor the first and second symbols twice but may interpret the received signal differently (e.g., PSS vs. SSS).

[0118] Additionally or alternatively, UE 120 may first attempt to decode the signal in the first symbol using the assumption that the signal is a PSS. If this fails, UE 120 may attempt to decode the signal in the first symbol using the assumption that the signal is an SSS. Similarly, UE 120 may first attempt to decode the signal in the second symbol using the assumption that the signal is an SSS. If this fails, UE 120 may attempt to decode the signal in the second symbol using the assumption that the signal is a PSS.

[0119] In some aspects, the UE 120 may monitor the third symbol for the PSS and the fourth symbol for the SSS only if the UE 120 supports CRS muting (e.g., only if the UE 120 is capable of communicating on a carrier that uses CRS muting). Additionally or alternatively, the UE 120 may attempt to acquire the PSS and / or SSS using the second symbol configuration only if the UE 120 supports CRS muting. Additionally or alternatively, the UE 120 may use different decoding assumptions to acquire the PSS and / or SSS in the first and / or second symbols only if the UE 120 supports CRS muting. For example, a UE 120 that supports CRS muting may be configured to perform the techniques described above, while a UE 120 that does not support CRS muting may be configured to attempt to acquire the PSS only in the first symbol and the SSS only in the second symbol. In this case, a UE 120 that does not support CRS muting may fail to acquire the PSS and / or SSS of a carrier that supports CRS muting (e.g., due to an error, such as when the PSS and SSS symbol positions are swapped). As a result, a UE 120 that does not support CRS muting may not be able to access (e.g., read its system information, camp on it, etc.) a carrier that supports CRS muting, thereby preventing the adverse effects described elsewhere herein.

[0120] As noted above, Figure 6 is provided as an example. Other examples are possible and may differ from those described with respect to Figure 6.

[0121] FIG. 7 is a diagram illustrating another example 700 related to preventing UEs that do not support CRS muting from camping on CRS-muted carriers, in accordance with various aspects of the present disclosure.

[0122] As indicated by reference numeral 710, the base station 110 may configure (e.g., set values ​​of) a first information element (IE), a second IE, and / or a third IE based at least in part on determining whether a carrier associated with the base station 110 uses CRS muting. In some aspects, the first IE (e.g., denoted as cellBarred) may indicate whether all UEs 120 that do not support CRS muting are barred from the carrier. The second IE (e.g., denoted as cellBarredCRS-Muting-r15) may indicate whether all UEs 120 that support CRS muting are barred from the carrier.

[0123] The third IE (e.g., denoted as cellReservedForOperatorUseCRS-Muting-r15) may indicate whether UEs 120 that support CRS muting and are in a particular set of access classes are excluded from the carriers. For example, in some aspects, one or more carriers may be reserved for use by UEs 120 in a first set of access classes (e.g., access classes 11 and 15), and UEs 120 in a second set of access classes (e.g., access classes 0-9 and 12-14) may be excluded from the one or more carriers. In some aspects, the first IE and / or the second IE may apply to all public land mobile networks (PLMNs). Additionally or alternatively, the third IE may be PLMN-specific and configured per PLMN.

[0124] For example, if the base station 110 determines that the base station 110's carrier uses CRS muting, the base station 110 may configure a first IE (e.g., by setting the first IE to a first value, such as "Barred") to indicate that all UEs that do not support CRS muting are barred from the carrier. Additionally or alternatively, if the base station 110 determines that the base station 110's carrier uses CRS muting, the base station 110 may configure a second IE (e.g., by setting the second IE to a second value, such as "Not Barred") to indicate that all UEs that support CRS muting are not barred from the carrier. In this way, legacy UEs 120 that do not support CRS muting may be barred from one or more carriers of the base station 110 (and / or all carriers of the base station 110) that use CRS muting, while UEs 120 that support CRS muting may be allowed to access these carriers.

[0125] As another example, if the base station 110 determines that the base station 110's carrier does not use CRS muting, the base station 110 may configure the first IE (e.g., by setting the first IE to a second value, such as "Not Barred") to indicate that all UEs that do not support CRS muting are not barred from the carrier. Additionally or alternatively, if the base station 110 determines that the base station 110's carrier does not use CRS muting, the base station 110 may also configure the second IE (e.g., by setting the second IE to a second value, such as "Not Barred") to indicate that all UEs that support CRS muting are not barred from the carrier. In this way, both legacy UEs 120 and UEs 120 that support CRS muting may be allowed to access carriers that do not use CRS muting.

[0126] As another example, if the base station 110 determines that the base station's 110 carrier uses CRS muting and that access to the carrier will be reserved (e.g., for operator use, for use by a particular set of access classes, etc.), the base station 110 may configure a first IE to indicate that UEs that do not support CRS muting are excluded from the carrier, may configure a second IE to indicate that all UEs that support CRS muting are excluded from the carrier, and may configure a third IE to indicate that access to the carrier is reserved for UEs that support CRS muting and are within a reserved set of access classes (e.g., access classes 11 and 15). In this way, only UEs 120 that support CRS muting and are within the reserved access classes may access the carrier.

[0127] As indicated by reference numeral 720, the first IE, the second IE, and / or the third IE may be transmitted by the base station 110 and received by the UE 120. In some aspects, the first IE, the second IE, and / or the third IE may be transmitted in system information (e.g., MIB, System Information Block (SIB), Minimum Residual System Information (RMSI), Other System Information (OSI), etc.).

[0128] As indicated by reference numeral 730, the UE 120 may selectively access (e.g., read information from, camp on, monitor, etc.) one or more carriers of the base station 110 based at least in part on the first IE, the second IE, and / or the third IE.

[0129] For example, if UE 120 does not support CRS muting, UE 120 may not access the carrier if the first IE indicates that all UEs that do not support CRS muting are barred from the carrier. However, if UE 120 does not support CRS muting, UE 120 may access the carrier if the first IE indicates that all UEs that do not support CRS muting are not barred from the carrier.

[0130] As another example, if UE 120 supports CRS muting, UE 120 may not access the carrier if the second IE indicates that all UEs that support CRS muting are barred from the carrier. However, if UE 120 supports CRS muting, UE 120 may access the carrier if the second IE indicates that all UEs that support CRS muting are not barred from the carrier. In this case, if UE 120 supports CRS muting, UE 120 may access the carrier regardless of the indication of the first IE if the second IE indicates that all UEs that support CRS muting are not barred from the carrier.

[0131] As another example, if UE 120 supports CRS muting and is in the reserved set of access classes (e.g., in access class 11 or 15), UE 120 may access the carrier if the second IE indicates that all UEs 120 that support CRS muting are excluded from the carrier, but the third IE indicates that all UEs 120 that support CRS muting and are in the reserved set of access classes are not excluded from the carrier. However, if UE 120 supports CRS muting and is not in the reserved set of access classes (e.g., in access classes 0-9 or 12-14), UE 120 may not access the carrier if the second IE indicates that all UEs 120 that support CRS muting are excluded from the carrier, and the third IE indicates that all UEs 120 that support CRS muting and are in the reserved set of access classes are not excluded from the carrier.

[0132] By using the above IE, UEs 120 that do not support CRS muting may be prevented from accessing carriers that support CRS muting, thereby preventing the adverse effects described elsewhere in this specification.

[0133] In some aspects, the first IE, the second IE, and / or the third IE may be configured for a UE 120 that cannot communicate with a 5G core network (e.g., a non-enhanced LTE (non-eLTE) UE 120). In some aspects, the first IE, the second IE, and / or the third IE may be configured for a UE 120 that can communicate with a 5G core network (e.g., an eLTE UE 120). In some aspects, two different IEs corresponding to the second IE may be used, where one IE is used for a UE 120 that cannot communicate with a 5G core network and another IE is used for a UE 120 that can communicate with a 5G core network. Additionally or alternatively, two different IEs corresponding to the third IE may be used, where one IE is used for a UE 120 that cannot communicate with a 5G core network and another IE is used for a UE 120 that can communicate with a 5G core network. Additional details are described below with respect to FIG. 8.

[0134] As noted above, Figure 7 is provided as an example. Other examples are possible and may differ from those described with respect to Figure 7.

[0135] FIG. 8 is a diagram illustrating another example 800 related to preventing UEs that do not support CRS muting from camping on CRS-muted carriers, in accordance with various aspects of the present disclosure.

[0136] 7, the base station 110 may configure (e.g., set values ​​of) a first information element (IE), a second IE, and / or a third IE based at least in part on determining whether a carrier associated with the base station 110 uses CRS muting. In some aspects, the first IE (e.g., denoted as cellBarred-5GC) may indicate whether all UEs 120 capable of communicating with a 5G core network and that do not support CRS muting have been barred from the carrier. The second IE (e.g., denoted as cellBarred5GC-CRS-Muting) may indicate whether all UEs 120 capable of communicating with a 5G core network and that support CRS muting have been barred from the carrier.

[0137] In a similar manner as described above with respect to FIG. 7, a third IE (e.g., shown as cellReservedForOperatorUs5GCeCRS-Muting) may be communicated to the 5G core network and may indicate whether a UE 120 that supports CRS muting and is within a particular set of access classes is excluded from the carrier. In some aspects, the first IE and / or the second IE may apply to all public land mobile networks (PLMNs). Additionally or alternatively, the third IE may be PLMN-specific and configured per PLMN.

[0138] In a similar manner as described above with respect to FIG. 7, the base station 110 may configure the first IE, the second IE, and / or the third IE for the UE 120 that can communicate with the 5G core network.

[0139] As indicated by reference numeral 820, the first IE, the second IE, and / or the third IE may be transmitted by the base station 110 and received by the UE 120. In some aspects, as described above with respect to FIG. 7, the first IE, the second IE, and / or the third IE may be transmitted in system information (e.g., MIB, System Information Block (SIB), Minimum Residual System Information (RMSI), Other System Information (OSI), etc.).

[0140] In a similar manner as described above with respect to FIG. 7, the UE 120 may selectively access (e.g., read information from, camp on, monitor, etc.) one or more carriers of the base station 110 based at least in part on the first IE, the second IE, and / or the third IE, as indicated by reference numeral 830. In some aspects, the UE 120 may read a first set of IEs (e.g., one or more of the IEs shown in and / or described with respect to FIG. 7) if the UE 120 is not able to communicate using a 5G core network, or may read a second set of IEs (e.g., one or more of the IEs shown in and / or described with respect to FIG. 8) if the UE 120 is able to communicate using a 5G core network. In some aspects, the UE 120 may read both sets of IEs (e.g., the first set and the second set) if the UE 120 is able to communicate with both a 5G core network and a 4G core network.

[0141] In some aspects, an IE may indicate whether a UE 120 that supports CRS muting, cannot access a 5G core network, and belongs to a non-reserved or regular access class is excluded or not excluded from camping on a carrier. Another IE may indicate whether a UE 120 that supports CRS muting, cannot access a 5G core network, and belongs to a reserved or special access class is excluded or not excluded from camping on a carrier. Another IE may indicate whether a UE 120 that supports CRS muting, can access a 5G core network, and belongs to a non-reserved or regular access class is excluded or not excluded from camping on a carrier. Another IE may indicate whether a UE 120 that supports CRS muting, can access a 5G core network, and belongs to a reserved or special access class is excluded or not excluded from camping on a carrier.

[0142] By using the above IE, UEs 120 that do not support CRS muting may be prevented from accessing carriers that support CRS muting, thereby preventing the adverse effects described elsewhere in this specification.

[0143] As noted above, Figure 8 is provided as an example. Other examples are possible and may differ from those described with respect to Figure 8.

[0144] FIG. 9 is a diagram illustrating another example 900 related to preventing UEs that do not support CRS muting from camping on CRS-muted carriers, in accordance with various aspects of the present disclosure.

[0145] As indicated by reference numeral 910, neighboring base station 110-2 may determine one or more carriers of neighboring base station 110-2 on which to use CRS muting.

[0146] As indicated by reference numeral 920, a neighboring base station 110-2 may transmit, and the serving base station 110-1 may receive, an indication of one or more carriers of the neighboring base station 110-2 that employ CRS muting. The carriers may be indicated using, for example, a first set of carrier identifiers that identify a set of carriers that support CRS muting, a second set of carrier identifiers that identify a set of carriers that do not support CRS muting, a binary indication of whether the neighboring base station 110-2 has any carriers that support CRS muting, etc. In some cases, the indication may comprise separate indications for different operating frequencies (e.g., bands, E-UTRA Absolute Radio Frequency Numbers (EARFCNs), etc.).

[0147] As indicated by reference numeral 930, the serving base station 110-1 may transmit, and the UE 120 may receive, an indication of one or more carriers of neighboring base station 110-2 that use CRS muting. Additionally or alternatively, the base station 110 may transmit, and the UE 120 may receive, an indication of whether any carriers of neighboring base station 110-2 use CRS muting. In some aspects, the indication may be included in a neighbor cell list. Additionally or alternatively, the indication may be included in system information, an RRC message, or the like.

[0148] As indicated by reference numeral 940, UE 120 may selectively access at least one of one or more carriers of neighboring base station 110-2 that supports CRS muting based at least in part on whether UE 120 supports CRS muting. For example, UE 120 may access at least one of one or more carriers that support CRS muting if UE 120 supports CRS muting. Alternatively, UE 120 may not access any of one or more carriers that support CRS muting if UE 120 does not support CRS muting. In this manner, resources for UEs 120 that do not support CRS muting may be conserved by preventing such UEs 120 from accessing carriers that use CRS muting.

[0149] As noted above, Figure 9 is provided as an example. Other examples are possible and may differ from those described with respect to Figure 9.

[0150] FIG. 10 is a diagram illustrating another example 1000 related to preventing UEs that do not support CRS muting from camping on CRS-muted carriers, in accordance with various aspects of the present disclosure.

[0151] As indicated by reference numeral 1010, UE 120 may determine whether UE 120 supports CRS muting. For example, this determination may be based at least in part on a configuration of UE 120.

[0152] As indicated by reference numeral 1020, the UE 120 may transmit, and the base station 110 may receive, a capability report (e.g., a UE capability report, etc.) indicating whether the UE 120 supports CRS muting. In some aspects, a bit in the capability report may be used to indicate (e.g., using a binary indication) whether the UE 120 supports CRS muting. In some aspects, the capability report may be transmitted from the base station 110 to a mobility management entity (MME) or other network entity.

[0153] As indicated by reference numeral 1030, the base station 110 may determine whether the base station 110 supports CRS muting. For example, this determination may be based at least in part on a configuration of the base station 110, a determination of whether one or more carriers and / or any carriers of the base station 110 use CRS muting, etc.

[0154] As indicated by reference numeral 1040, the base station 110 and / or MME (or a similar network entity) may selectively page the UE 120 on a carrier based at least in part on whether the UE 120 supports CRS muting for that carrier and whether the base station 110 supports CRS muting. In some aspects, if the base station 110 supports CRS muting and the UE 120 does not support CRS muting, the base station 110 may not page the UE 120 on any carrier. Alternatively, if the base station 110 supports CRS muting and the UE 120 does not support CRS muting, the base station 110 may not page the UE 120 on a carrier that uses CRS muting, but may page the UE 120 on a carrier that does not use CRS muting. In some cases, the base station 110 and / or MME may page the UE 120 that does not support CRS muting only on carriers and / or base stations 110 that do not support CRS muting.

[0155] In some aspects, the base station 110 may page the UE 120 if the base station 110 supports CRS muting and the UE 120 supports CRS muting. Additionally or alternatively, the base station 110 may page the UE 120 if the base station 110 does not support CRS muting and the UE 120 does not support CRS muting. Additionally or alternatively, the base station 110 may page the UE 120 if the base station 110 does not support CRS muting and the UE 120 supports CRS muting.

[0156] In some aspects, the core network may initiate a page, but the core network may not be informed of UE capabilities. In this case, the core network may instruct the base station 110 to page the UE 120, but the base station 110 may discard the page (e.g., on a carrier that uses CRS muting) when the base station 110 supports CRS muting and the UE 120 does not support CRS muting. In some aspects (e.g., when the RRC inactive function is activated), the base station 110 may initiate a page. In this case, the base station 110 may prevent the initiation and / or transmission of a page addressed to the UE 120 when the base station 110 supports CRS muting and the UE 120 does not support CRS muting.

[0157] By signaling the UE capabilities for CRS muting as described above, base station 110 resources can be conserved by preventing the transmission of unnecessary pages, and network resources that would otherwise be used for those pages can also be conserved.

[0158] As noted above, Figure 10 is provided as an example. Other examples are possible and may differ from those described with respect to Figure 10.

[0159] 11 illustrates an example process 1100, performed by, for example, a base station, in accordance with various aspects of the present disclosure. The example process 1100 is an example of a base station (e.g., base station 110) performing operations related to preventing UEs that do not support CRS muting from camping on a CRS-muted carrier.

[0160] 11, in some aspects, process 1100 may include determining whether a carrier associated with the base station uses cell-specific reference signal (CRS) muting (block 1110). For example, as described above with respect to FIG. 5, the base station (e.g., using controller / processor 240, etc.) may determine whether a carrier associated with the base station uses CRS muting.

[0161] 11, in some aspects, process 1100 may include determining a master information block (MIB) scrambling sequence or a physical broadcast channel (PBCH) scrambling sequence to be used to scramble the MIB or PBCH of the carrier based at least in part on whether the carrier uses CRS muting (block 1120). For example, as described above with respect to FIG. 5, the base station (e.g., using controller / processor 240, etc.) may determine a MIB scrambling sequence and / or a PBCH scrambling sequence to be used to scramble the MIB and / or PBCH of the carrier based at least in part on whether the carrier uses CRS muting.

[0162] 11 , in some aspects, process 1100 may include transmitting a MIB or a PBCH, where the MIB or the PBCH is scrambled using the determined MIB scrambling sequence or the determined PBCH scrambling sequence (block 1130). For example, as described above with respect to FIG. 5 , the base station may transmit the MIB and / or the PBCH (e.g., using controller / processor 240, transmit processor 220, TX MIMO processor 230, MOD 232, antennas 234, etc.). In some aspects, the MIB is scrambled using the determined MIB scrambling sequence and / or the PBCH is scrambled using the determined PBCH scrambling sequence.

[0163] Process 1100 may include additional aspects, such as any single aspect or any combination of aspects described below, and / or with respect to one or more other processes described elsewhere herein.

[0164] In a first aspect, the MIB scrambling sequence or the PBCH scrambling sequence is generated using a first scrambling sequence initialization when the carrier does not use CRS muting.

[0165] In a second aspect, alone or in combination with the first aspect, the MIB scrambling sequence or the PBCH scrambling sequence is generated using a second scrambling sequence initialization when the carrier uses CRS muting.

[0166] In a third aspect, alone or in combination with one or more of the first and second aspects, the first scrambling sequence initialization uses a physical cell identifier.

[0167] In a fourth aspect, either alone or in combination with one or more of the first to third aspects, the second scrambling sequence initialization uses a physical cell identifier plus a predetermined value.

[0168] 11 illustrates example blocks of process 1100, in some aspects process 1100 may include additional blocks, fewer blocks, different blocks, or blocks that are arranged differently than the blocks illustrated in FIG 11. Additionally or alternatively, two or more of the blocks of process 1100 may be performed in parallel.

[0169] 12 illustrates an example process 1200, performed, for example, by a UE, in accordance with various aspects of the present disclosure. The example process 1200 is an example of a UE (such as, for example, UE 120) performing operations related to preventing UEs that do not support CRS muting from camping on a CRS-muted carrier.

[0170] 12, in some aspects, process 1200 may include receiving a master information block (MIB) or a physical broadcast channel (PBCH) (block 1210). For example, as described above with respect to FIG. 5, the UE may receive the MIB and / or the PBCH (e.g., using antennas 252, DEMOD 254, MIMO detector 256, receive processor 258, controller / processor 280, etc.).

[0171] 12, in some aspects, process 1200 may include determining that descrambling the MIB or the PBCH based at least in part on the first scrambling sequence will result in an error (block 1220). For example, as described above with respect to FIG. 5, the UE (e.g., using controller / processor 280, etc.) may determine that descrambling the MIB and / or the PBCH based at least in part on the first scrambling sequence will result in an error.

[0172] 12, in some aspects, process 1200 may include descrambling the MIB or PBCH based at least in part on the second scrambling sequence based at least in part on determining that descrambling the MIB or PBCH based at least in part on the first scrambling sequence would result in an error (block 1230). For example, as described above with respect to FIG. 5, the UE (e.g., using antennas 252, DEMOD 254, MIMO detector 256, receive processor 258, controller / processor 280, etc.) may descramble the MIB and / or PBCH based at least in part on the second scrambling sequence based at least in part on determining that descrambling the MIB and / or PBCH based at least in part on the first scrambling sequence would result in an error.

[0173] Process 1200 may include additional aspects, such as any single aspect or any combination of aspects described below, and / or with respect to one or more other processes described elsewhere herein.

[0174] In a first aspect, the first scrambling sequence is based at least in part on a physical cell identifier.

[0175] In a second aspect, alone or in combination with the first aspect, the second scrambling sequence is based at least in part on the physical cell identifier plus a predetermined value.

[0176] In a third aspect, either alone or in combination with one or more of the first and second aspects, based at least in part on a determination that the UE supports cell-specific reference signal (CRS) muting, the MIB or PBCH is descrambled based at least in part on a second scrambling sequence.

[0177] 12 illustrates example blocks of process 1200, in some aspects process 1200 may include additional blocks, fewer blocks, different blocks, or blocks that are arranged differently than the blocks illustrated in FIG 12. Additionally or alternatively, two or more of the blocks of process 1200 may be performed in parallel.

[0178] 13 illustrates an example process 1300, performed by, for example, a base station, in accordance with various aspects of the present disclosure. The example process 1300 is an example of a base station (e.g., base station 110, etc.) performing operations related to preventing UEs that do not support CRS muting from camping on a CRS-muted carrier.

[0179] 13, in some aspects, process 1300 may include determining whether a carrier associated with the base station uses cell-specific reference signal (CRS) muting (block 1310). For example, as described above with respect to FIG. 6, the base station (e.g., using controller / processor 240, etc.) may determine whether a carrier associated with the base station uses CRS muting.

[0180] 13, in some aspects, the process 1300 may include determining a first symbol to be used to transmit a primary synchronization signal (PSS) and a second symbol to be used to transmit a secondary synchronization signal (SSS) based at least in part on whether the carrier uses CRS muting (block 1320). For example, as described above with respect to FIG. 6, the base station (e.g., using the controller / processor 240, etc.) may determine a first symbol to be used to transmit a PSS and a second symbol to be used to transmit a SSS based at least in part on whether the carrier uses CRS muting.

[0181] 13, in some aspects, process 1300 may include transmitting the PSS in the first symbol and the SSS in the second symbol (block 1330). For example, as described above with respect to FIG. 6, the base station (e.g., using controller / processor 240, transmit processor 220, TX MIMO processor 230, MOD 232, antennas 234, etc.) may transmit the PSS in the first symbol and the SSS in the second symbol.

[0182] Process 1300 may include additional aspects, such as any single aspect or any combination of aspects described below, and / or with respect to one or more other processes described elsewhere herein.

[0183] In a first aspect, the first symbol and the second symbol follow a first symbol configuration when the carrier does not use CRS muting.

[0184] In a second aspect, alone or in combination with the first aspect, the first symbol and the second symbol follow a second symbol configuration when the carrier uses CRS muting.

[0185] In a third aspect, either alone or in combination with one or more of the first and second aspects, the second symbol precedes the first symbol in the first symbol configuration.

[0186] In a fourth aspect, either alone or in combination with one or more of the first to third aspects, a first symbol precedes a second symbol in a second symbol configuration.

[0187] 13 illustrates example blocks of process 1300, in some aspects process 1300 may include additional blocks, fewer blocks, different blocks, or blocks that are arranged differently than the blocks illustrated in FIG 13. Additionally or alternatively, two or more of the blocks of process 1300 may be performed in parallel.

[0188] 14 illustrates an example process 1400, performed by, for example, a UE, in accordance with various aspects of the present disclosure. The example process 1400 is an example of a UE (such as, for example, UE 120) performing operations related to preventing UEs that do not support CRS muting from camping on a CRS-muted carrier.

[0189] 14, in some aspects, the process 1400 may include determining that a primary synchronization signal (PSS) or a secondary synchronization signal (SSS) is not present in a corresponding first symbol or second symbol (block 1410). For example, as described above with respect to FIG. 6, the UE (e.g., using the controller / processor 280, etc.) may determine that a PSS or SSS is not present in a corresponding first symbol or second symbol.

[0190] 14 , in some aspects, process 1400 may include monitoring a third symbol for a PSS and a fourth symbol for an SSS based at least in part on determining that a PSS or an SSS is not present in the corresponding first or second symbol, where the third symbol has a different symbol position within the resource block than the first symbol and the fourth symbol has a different symbol position within the resource block than the second symbol (block 1420). For example, as described above with respect to FIG. 6 , the UE may (e.g., using antenna 252, DEMOD 254, MIMO detector 256, receive processor 258, controller / processor 280, etc.) monitor a third symbol for a PSS and a fourth symbol for an SSS based at least in part on determining that a PSS or an SSS is not present in the corresponding first or second symbol. In some aspects, the third symbol has a different symbol position within the resource block than the first symbol. In some aspects, the fourth symbol has a different symbol position within the resource block than the second symbol.

[0191] Process 1400 may include additional aspects, such as any single aspect or any combination of aspects described below, and / or with respect to one or more other processes described elsewhere herein.

[0192] In a first aspect, the third symbol has the same symbol position as the second symbol within the resource block.

[0193] In a second aspect, alone or in combination with the first aspect, the fourth symbol has the same symbol position within the resource block as the first symbol.

[0194] In a third aspect, either alone or in combination with one or more of the first and second aspects, the third and fourth symbols are monitored based at least in part on a determination that the UE supports CRS muting.

[0195] Although Figure 14 illustrates example blocks of process 1400, in some aspects process 1400 may include additional blocks, fewer blocks, different blocks, or blocks that are arranged differently than the blocks illustrated in Figure 14. Additionally or alternatively, two or more of the blocks of process 1400 may be performed in parallel.

[0196] 15 illustrates an example process 1500, performed by, for example, a base station, in accordance with various aspects of the present disclosure. The example process 1500 is an example of a base station (e.g., base station 110, etc.) performing operations related to preventing UEs that do not support CRS muting from camping on a CRS-muted carrier.

[0197] 15, in some aspects, process 1500 may include determining whether a carrier associated with the base station uses cell-specific reference signal (CRS) muting (block 1510). For example, as described above with respect to FIGS. 7-8, the base station (e.g., using controller / processor 240, etc.) may determine whether a carrier associated with the base station uses CRS muting.

[0198] As further shown in FIG. 15 , in some aspects, process 1500 may include configuring a first information element (IE) and a second IE based at least in part on determining whether a carrier uses CRS muting, where the first IE indicates whether all user equipment (UE) that does not support CRS muting has been barred from the carrier, and the second IE indicates whether all UEs that support CRS muting have been barred from the carrier (block 1520). For example, as described above with respect to FIGS. 7-8 , a base station (e.g., using controller / processor 240, etc.) may configure the first information element (IE) and the second IE based at least in part on determining whether a carrier uses CRS muting. In some aspects, the first IE indicates whether all UEs that do not support CRS muting have been barred from the carrier. In some aspects, the second IE indicates whether all UEs that support CRS muting have been barred from the carrier.

[0199] 15, in some aspects, process 1500 may include transmitting the first IE and the second IE to the UE (block 1530). For example, as described above with respect to FIGS. 7-8, the base station (e.g., using controller / processor 240, transmit processor 220, TX MIMO processor 230, MOD 232, antennas 234, etc.) may transmit the first IE and the second IE to the UE.

[0200] Process 1500 may include additional aspects, such as any single aspect or any combination of aspects described below, and / or with respect to one or more other processes described elsewhere herein.

[0201] In a first aspect, based at least in part on a carrier's decision to use CRS muting, the first IE is configured to indicate that all UEs that do not support CRS muting are barred from the carrier, and the second IE is configured to indicate that all UEs that support CRS muting are not barred from the carrier.

[0202] In a second aspect, alone or in combination with the first aspect, at least one of the first IE or the second IE is for a UE that is not capable of communicating with the 5G core network.

[0203] In a third aspect, alone or in combination with one or more of the first and second aspects, at least one of the first IE or the second IE is for a UE capable of communicating with a 5G core network.

[0204] In a fourth aspect, alone or in combination with one or more of the first to third aspects, the base station may configure a third IE based at least in part on determining whether the carrier uses CRS muting, the third IE indicating whether UEs that support CRS muting and are in a particular set of access classes are excluded from the carrier, and may send the third IE to the UE.

[0205] In a fifth aspect, alone or in combination with one or more of the first to fourth aspects, based at least in part on a determination that the carrier uses CRS muting and that access to the carrier will be reserved for operator use, a first IE is configured to indicate that all UEs that do not support CRS muting are excluded from the carrier, a second IE is configured to indicate that all UEs that support CRS muting are excluded from the carrier, and a third IE is configured to indicate that access to the carrier is reserved for UEs that are not in a particular set of access classes.

[0206] In a sixth aspect, alone or in combination with one or more of the first to fifth aspects, the indication of the third IE is Public Land Mobile Network (PLMN) specific.

[0207] In a seventh aspect, alone or in combination with one or more of the first to sixth aspects, the third IE is for a UE that is not capable of communicating with a 5G core network.

[0208] In an eighth aspect, alone or in combination with one or more of the first to seventh aspects, the third IE is for a UE capable of communicating with a 5G core network.

[0209] In a ninth aspect, alone or in combination with one or more of the first through eighth aspects, the process 1500 includes receiving an indication from a neighboring base station of one or more carriers of the neighboring base station that employ CRS muting, and transmitting information to the UE identifying the one or more carriers of the neighboring base station that employ CRS muting.

[0210] In a tenth aspect, alone or in combination with one or more of the first to ninth aspects, the information is transmitted in at least one of a neighbor cell list, system information, a radio resource control message, or a combination thereof.

[0211] In an eleventh aspect, alone or in combination with one or more of the first through tenth aspects, the process 1500 includes receiving a capability report indicating whether the UE supports CRS muting.

[0212] Although Figure 15 illustrates example blocks of process 1500, in some aspects process 1500 may include additional blocks, fewer blocks, different blocks, or blocks that are arranged differently than the blocks illustrated in Figure 15. Additionally or alternatively, two or more of the blocks of process 1500 may be performed in parallel.

[0213] 16 illustrates an example process 1600, performed by, for example, a UE, in accordance with various aspects of the present disclosure. The example process 1600 is an example of a UE (such as, for example, UE 120) performing operations related to preventing UEs that do not support CRS muting from camping on a CRS-muted carrier.

[0214] As shown in FIG. 16 , in some aspects, process 1600 may include receiving a first information element (IE) and a second IE, where the first IE indicates whether all UEs that do not support cell-specific reference signal (CRS) muting are barred from the carrier, and the second IE indicates whether all UEs that support CRS muting are barred from the carrier (block 1610). For example, as described above with respect to FIGS. 7-8 , the UE may receive the first IE and the second IE (e.g., using antenna 252, DEMOD 254, MIMO detector 256, receive processor 258, controller / processor 280, etc.). In some aspects, the first IE indicates whether all UEs that do not support CRS muting are barred from the carrier. In some aspects, the second IE indicates whether all UEs that support CRS muting are barred from the carrier.

[0215] 16, in some aspects, the process 1600 may include selectively accessing a carrier based at least in part on at least one of the first IE or the second IE (block 1620). For example, as described above with respect to FIGS. 7-8, the UE may (e.g., using the antennas 252, the DEMOD 254, the MIMO detector 256, the receive processor 258, the controller / processor 280, etc.) selectively access a carrier based at least in part on at least one of the first IE or the second IE.

[0216] Process 1600 may include additional aspects, such as any single aspect or any combination of aspects described below, and / or with respect to one or more other processes described elsewhere herein.

[0217] In a first aspect, when the UE does not support CRS muting and the first IE indicates that all UEs that do not support CRS muting are excluded from the carrier, the carrier is not accessed.

[0218] In a second aspect, alone or in combination with the first aspect, a carrier is accessed when the UE does not support CRS muting and the first IE indicates that all UEs that do not support CRS muting are not excluded from the carrier.

[0219] In a third aspect, alone or in combination with one or more of the first and second aspects, when the UE supports CRS muting and the second IE indicates that all UEs that support CRS muting are excluded from the carrier, the carrier is not accessed.

[0220] In a fourth aspect, either alone or in combination with one or more of the first to third aspects, the carrier is accessed when the UE supports CRS muting and the second IE indicates that all UEs that support CRS muting are not excluded from the carrier.

[0221] In a fifth aspect, either alone or in combination with one or more of the first to fourth aspects, when the UE supports CRS muting and the second IE indicates that all UEs that support CRS muting are not excluded from the carrier, the carrier is accessed regardless of the indication of the first IE.

[0222] In a sixth aspect, either alone or in combination with one or more of the first to fifth aspects, at least one of the first IE or the second IE is for a UE that is not capable of communicating with the 5G core network.

[0223] In a seventh aspect, either alone or in combination with one or more of the first to sixth aspects, at least one of the first IE or the second IE is for a UE capable of communicating with a 5G core network.

[0224] In an eighth aspect, alone or in combination with one or more of the first through seventh aspects, the UE may receive a third IE, the third IE indicating whether UEs that support CRS muting and are in a particular set of access classes are excluded from the carrier, and may selectively access the carrier based at least in part on at least one of the first IE, the second IE, or the third IE.

[0225] In a ninth aspect, alone or in combination with one or more of the first to eighth aspects, the indication of the third IE is public land mobile network (PLMN) specific.

[0226] In a tenth aspect, alone or in combination with one or more of the first to ninth aspects, the third IE is for a UE that is not capable of communicating with a 5G core network.

[0227] In an eleventh aspect, alone or in combination with one or more of the first to tenth aspects, the third IE is for a UE capable of communicating with a 5G core network.

[0228] In a twelfth aspect, alone or in combination with one or more of the first through eleventh aspects, the process 1600 includes receiving an indication of one or more carriers of a neighboring base station from a serving base station that uses CRS muting, and selectively accessing at least one of the one or more carriers based at least in part on whether the UE supports CRS muting.

[0229] In a thirteenth aspect, alone or in combination with one or more of the first to twelfth aspects, the indication is received in at least one of a neighbor cell list, system information, a radio resource control message, or a combination thereof.

[0230] In a fourteenth aspect, alone or in combination with one or more of the first through thirteenth aspects, the process 1600 includes transmitting a capability report indicating whether the UE supports CRS muting.

[0231] Although Figure 16 illustrates example blocks of process 1600, in some aspects process 1600 may include additional blocks, fewer blocks, different blocks, or blocks that are arranged differently than the blocks illustrated in Figure 16. Additionally or alternatively, two or more of the blocks of process 1600 may be performed in parallel.

[0232] 17 illustrates an example process 1700, performed by, for example, a base station, in accordance with various aspects of the present disclosure. The example process 1700 is an example of a base station (e.g., base station 110, etc.) performing operations related to preventing UEs that do not support CRS muting from camping on a CRS-muted carrier.

[0233] 17, in some aspects, process 1700 may include receiving, from a neighboring base station, an indication of one or more carriers of the neighboring base station that employ cell-specific reference signal (CRS) muting (block 1710). For example, as described above with respect to FIG. 9, the base station may receive (e.g., using antennas 234, DEMOD 232, MIMO detector 236, receive processor 238, controller / processor 240, etc.) an indication of one or more carriers of the neighboring base station that employ CRS muting from the neighboring base station.

[0234] 17, in some aspects, process 1700 may include transmitting information to a user equipment (UE) identifying one or more carriers of a neighboring base station that employ CRS muting (block 1720). For example, as described above with respect to FIG. 9, a base station (e.g., using controller / processor 240, transmit processor 220, TX MIMO processor 230, MOD 232, antennas 234, etc.) may transmit information to a UE identifying one or more carriers of a neighboring base station that employ CRS muting.

[0235] Process 1700 may include additional aspects, such as any single aspect or any combination of aspects described below, and / or with respect to one or more other processes described elsewhere herein.

[0236] In a first aspect, the information is transmitted in a neighbor cell list.

[0237] In a second aspect, alone or in combination with the first aspect, the information is transmitted in at least one of system information, a radio resource control (RRC) message, or some combination thereof.

[0238] Although Figure 17 illustrates example blocks of process 1700, in some aspects process 1700 may include additional blocks, fewer blocks, different blocks, or blocks that are arranged differently than the blocks illustrated in Figure 17. Additionally or alternatively, two or more of the blocks of process 1700 may be performed in parallel.

[0239] 18 illustrates an example process 1800, performed, for example, by a UE, in accordance with various aspects of the present disclosure. The example process 1800 is an example of a UE (such as, for example, UE 120) performing operations related to preventing UEs that do not support CRS muting from camping on a CRS-muted carrier.

[0240] 18, in some aspects, process 1800 may include receiving an indication of one or more carriers of a neighboring base station from a serving base station that employs cell-specific reference signal (CRS) muting (block 1810). For example, as described above with respect to FIG. 9, the UE may receive (e.g., using antennas 252, DEMOD 254, MIMO detector 256, receive processor 258, controller / processor 280, etc.) an indication of one or more carriers of a neighboring base station that employs CRS muting from the serving base station.

[0241] 18, in some aspects, the process 1800 may include selectively accessing at least one of the one or more carriers based at least in part on whether the UE supports CRS muting (block 1820). For example, as described above with respect to FIG. 9, the UE may (e.g., using the antennas 252, the DEMOD 254, the MIMO detector 256, the receive processor 258, the controller / processor 280, etc.) selectively access at least one of the one or more carriers based at least in part on whether the UE supports CRS muting.

[0242] Process 1800 may include additional aspects, such as any single aspect or any combination of aspects described below, and / or with respect to one or more other processes described elsewhere herein.

[0243] In a first aspect, the indication is received in a neighbor cell list.

[0244] In a second aspect, alone or in combination with the first aspect, the indication is received in at least one of system information, a radio resource control (RRC) message, or some combination thereof.

[0245] In a third aspect, alone or in combination with one or more of the first and second aspects, at least one of the one or more carriers is accessed when the UE supports CRS muting.

[0246] In a fourth aspect, either alone or in combination with one or more of the first to third aspects, one or more carriers are not accessed when the UE does not support CRS muting.

[0247] Although Figure 18 illustrates example blocks of process 1800, in some aspects process 1800 may include additional blocks, fewer blocks, different blocks, or blocks that are arranged differently than the blocks illustrated in Figure 18. Additionally or alternatively, two or more of the blocks of process 1800 may be performed in parallel.

[0248] 19 illustrates an example process 1900, performed by, for example, a base station, in accordance with various aspects of the present disclosure. The example process 1900 is an example of a base station (e.g., base station 110, etc.) performing operations related to preventing UEs that do not support CRS muting from camping on a CRS-muted carrier.

[0249] 19, in some aspects, process 1900 may include receiving a capability report from a user equipment (UE) indicating whether the UE supports cell-specific reference signal (CRS) muting (block 1910). For example, as described above with respect to FIG. 10, the base station (e.g., using antennas 234, DEMOD 232, MIMO detector 236, receive processor 238, controller / processor 240, etc.) may receive a capability report from the UE indicating whether the UE supports CRS muting.

[0250] 19, in some aspects, the process 1900 may include determining whether the base station supports CRS muting (block 1920). For example, as described above with respect to FIG. 10, the base station (e.g., using the controller / processor 240, etc.) may determine whether the base station supports CRS muting.

[0251] 19, in some aspects, process 1900 may include selectively paging the UE on a carrier based at least in part on whether the UE supports CRS muting for that carrier and whether the base station supports CRS muting (block 1930). For example, as described above with respect to FIG. 10, the base station (e.g., using controller / processor 240, transmit processor 220, TX MIMO processor 230, MOD 232, antennas 234, etc.) may selectively page the UE on a carrier based at least in part on whether the UE supports CRS muting for that carrier and whether the base station supports CRS muting.

[0252] Process 1900 may include additional aspects, such as any single aspect or any combination of aspects described below, and / or with respect to one or more other processes described elsewhere herein.

[0253] In a first aspect, the UE is not paged on the carrier when the base station supports CRS muting and the UE does not support CRS muting.

[0254] In a second aspect, alone or in combination with the first aspect, the base station discards a page received from the core network and addressed to the UE when the base station supports CRS muting and the UE does not support CRS muting.

[0255] In a third aspect, alone or in combination with one or more of the first and second aspects, the base station prevents the base station from initiating a page when the base station supports CRS muting and the UE does not support CRS muting.

[0256] In a fourth aspect, either alone or in combination with one or more of the first to third aspects, a base station pages a UE on a different carrier that does not use CRS muting when the base station supports CRS muting on a carrier and the UE does not support CRS muting.

[0257] In a fifth aspect, either alone or in combination with one or more of the first to fourth aspects, the UE is paged when the base station supports CRS muting and the UE supports CRS muting, or the base station does not support CRS muting and the UE does not support CRS muting, or the base station does not support CRS muting and the UE supports CRS muting.

[0258] Although Figure 19 illustrates example blocks of process 1900, in some aspects process 1900 may include additional blocks, fewer blocks, different blocks, or blocks that are arranged differently than the blocks illustrated in Figure 19. Additionally or alternatively, two or more of the blocks of process 1900 may be performed in parallel.

[0259] 20 illustrates an example process 2000, performed, for example, by a UE, in accordance with various aspects of the present disclosure. The example process 2000 is an example of a UE (e.g., UE 120) performing operations related to preventing UEs that do not support CRS muting from camping on a CRS-muted carrier.

[0260] 20, in some aspects, the process 2000 may include determining whether the UE supports cell-specific reference signal (CRS) muting (block 2010). For example, as described above with respect to FIG. 10, the UE (e.g., using the controller / processor 280, etc.) may determine whether the UE supports CRS muting.

[0261] 20, in some aspects, process 2000 may include transmitting a capability report to the base station indicating whether the UE supports CRS muting (block 2020). For example, as described above with respect to FIG. 10, the UE (e.g., using controller / processor 280, transmit processor 264, TX MIMO processor 266, MOD 254, antennas 252, etc.) may transmit a capability report to the base station indicating whether the UE supports CRS muting.

[0262] Process 2000 may include additional aspects, such as any single aspect or any combination of aspects described with respect to one or more other processes described elsewhere herein.

[0263] 20 illustrates example blocks of process 2000, in some aspects process 2000 may include additional blocks, fewer blocks, different blocks, or blocks that are configured differently than the blocks illustrated in FIG 20. Additionally or alternatively, two or more of the blocks of process 2000 may be performed in parallel.

[0264] The above disclosure provides illustration and description, and is not intended to be exhaustive or to limit the embodiments to the precise form disclosed. Modifications and variations are possible in light of the above disclosure or may be acquired from practice of the embodiments.

[0265] As used herein, the term "component" is intended to be broadly interpreted as hardware, firmware, or a combination of hardware and software. As used herein, a "processor" is implemented in hardware, firmware, or a combination of hardware and software.

[0266] Several aspects are described herein with respect to thresholds. As used herein, "meeting a threshold" may refer to a value being greater than the threshold, greater than or equal to the threshold, less than the threshold, less than or equal to the threshold, equal to the threshold, not equal to the threshold, etc.

[0267] It will be apparent that the systems and / or methods described herein may be implemented in various forms of hardware, firmware, or combinations of hardware and software. The actual dedicated control hardware or software code used to implement these systems and / or methods is not limiting. Thus, the operation and behavior of the systems and / or methods are described herein without reference to specific software code—it will be understood that software and hardware can be designed to implement the systems and / or methods based at least in part on the description herein.

[0268] Although particular combinations of features are recited in the claims and / or disclosed herein, these combinations do not limit the disclosure of possible embodiments. Indeed, many of these features may be combined in ways not specifically recited in the claims and / or disclosed herein. Although each dependent claim listed below may directly depend on only one claim, the disclosure of possible embodiments includes each dependent claim combined with every other claim in the claim set. A phrase referring to "at least one of" a list of items refers to any combination of those items, including single members. As an example, "at least one of a, b, or c" is intended to encompass a, b, c, ab, ac, bc, and abc, as well as any combination of multiple identical elements (e.g., aa, aaa, aab, aac, abb, acc, bb, bbb, bbc, cc, and ccc, or any other order of a, b, and c).

[0269] No element, act, or instruction used herein should be considered critical or required unless explicitly described as such. Also, as used herein, the articles "a" and "an" include one or more items and may be used interchangeably with "one or more." Furthermore, as used herein, the terms "set" and "group" include one or more items (e.g., related items, unrelated items, combinations of related and unrelated items, etc.) and may be used interchangeably with "one or more." Where only one item is intended, the term "one" or similar language is used. Also, as used herein, terms such as "has," "have," and "having" are intended to be open-ended terms. Furthermore, the phrase "based on" is intended to mean "based at least in part on," unless otherwise specified. [Explanation of symbols]

[0270] 100 Network, Access Network 102a Macrocell 102b Picocell 102c Femtocell 110 Base station (BS) 110a BS, Macro BS 110b BS, Pico BS 110c BS, Femto BS 110d BS, relay station, relay BS 110-1 Serving base station 110-2 Nearby base station 120 User Equipment (UE) 130 Network Controller 212 Data Sources 220 Transmit Processor 230 Transmit (TX) Multiple Input Multiple Output (MIMO) Processor 232 Modulator (MOD) / Demodulator (DEMOD) 234 Antenna 236 MIMO detector 238 Receive Processor 239 Data Sink 240 Controllers / Processors 242 memory 244 communication unit 246 Scheduler 252 Antenna 254 Modulator (MOD) / Demodulator (DEMOD) 256 MIMO detector 258 Receive Processor 260 Data Sink 262 Data Sources 264 Transmit Processor 266 Transmit (TX) Multiple Input Multiple Output (MIMO) Processor 280 Controller / Processor 282 memory 290 Controller / Processor 292 memory 294 Communication Unit 300 frame structure 410 slot format

Claims

1. 1. A method of wireless communication performed by a user equipment (UE), comprising: determining that a primary synchronization signal (PSS) or a secondary synchronization signal (SSS) is absent in a corresponding first symbol or second symbol; and monitoring a third symbol for the PSS and a fourth symbol for the SSS based at least in part on determining that the PSS or the SSS is not present in the corresponding first symbol or second symbol, wherein the third symbol has a different symbol position within a resource block than the first symbol and the fourth symbol has a different symbol position within the resource block than the second symbol. method.

2. 2. The method of claim 1, wherein the third symbol has the same symbol position within the resource block as the second symbol, and the fourth symbol has the same symbol position within the resource block as the first symbol.

3. 10. The method of claim 1, wherein the third symbol and the fourth symbol are monitored based at least in part on a determination that the UE supports cell-specific reference signal (CRS) muting.

4. A user equipment comprising means for performing the method according to any one of claims 1 to 3.

5. A computer program comprising instructions for causing the user equipment to perform the method of any one of claims 1 to 3.

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