WO2021114123A1

WO2021114123A1 - Establishing wireless connections with nonstandalone (nsa) -anchor long term evolution (lte) cells

Info

Publication number: WO2021114123A1
Application number: PCT/CN2019/124452
Authority: WO
Inventors: Jinglei TIAN; Xiaochen Chen; Jianqiang Zhang; Hewu GU; Jun Deng; Zhenqing CUI; Jie Mao; Tom Chin; Zhongyue LOU
Original assignee: Qualcomm Incorporated
Priority date: 2019-12-11
Filing date: 2019-12-11
Publication date: 2021-06-17

Abstract

This disclosure provides systems, methods and apparatuses for establishing wireless connections with nonstandalone (NSA) -anchor Long Term Evolution (LTE) cells. In one aspect, a mobile device may perform a first frequency scan for one or more NSA-anchor LTE cells. The mobile device may determine whether a LTE base station is configured as an NSA-anchor LTE cell based on the first frequency scan. The mobile device may, in response to determining that the LTE base station is configured as the NSA-anchor LTE cell, camp on the LTE base station configured as the NSA-anchor LTE cell. Camping, and connecting to the NSA-anchor LTE cell may result in higher data throughput at the mobile device, and may improve overall user experience.

Description

ESTABLISHING WIRELESS CONNECTIONS WITH NONSTANDALONE (NSA) -ANCHOR LONG TERM EVOLUTION (LTE) CELLS

TECHNICAL FIELD

Aspects of the present disclosure relate generally to wireless communication, and more particularly to techniques for establishing wireless connections with nonstandalone (NSA) -anchor Long Term Evolution (LTE) cells.

DESCRIPTION OF THE RELATED TECHNOLOGY

Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, and broadcasts. Typical wireless communication systems may employ multiple-access technologies capable of supporting communication with multiple users by sharing available system resources (for example, 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 enhancements to the Universal Mobile Telecommunications System (UMTS) mobile standard promulgated by the Third Generation Partnership Project (3GPP) .

A wireless communication network may include a number of base stations (BSs) that can support communication for a number of user equipment (UEs) . A user equipment (UE) may communicate with a base station (BS) via the downlink (DL) and uplink (UL) . The DL (or forward link) refers to the communication link from the BS to the UE, and the UL (or reverse link) refers to the communication link from the UE to the BS. As will be described in more detail herein, a BS may be referred to as a NodeB, an LTE evolved nodeB (eNB) , a master node (MeNB) , a gNB, a secondary node (SgNB) , an access point (AP) , a radio head, a transmit receive point (TRP) , a New Radio (NR) BS, a 5G NodeB, or the like.

The above multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different UEs to communicate on a municipal, national, regional, and even global level. NR, which also may be referred to as 5G, is a set of enhancements to the LTE mobile standard promulgated by the Third Generation Partnership Project (3GPP) . NR is designed to better support mobile broadband Internet access by improving spectral efficiency, lowering costs, improving services, making use of new spectrum, and better integrating with other open standards using orthogonal frequency-division multiplexing (OFDM) with a cyclic prefix (CP) (CP-OFDM) on the DL, using CP-OFDM or SC-FDM (for example, also known as discrete Fourier transform spread OFDM (DFT-s-OFDM) ) on the UL (or a combination thereof) , as well as supporting beamforming, multiple-input multiple-output (MIMO) antenna technology, and carrier aggregation.

SUMMARY

The systems, methods, and devices of this disclosure each have several innovative aspects, no single one of which is solely responsible for the desirable attributes disclosed herein.

One innovative aspect of the subject matter described in this disclosure can be implemented in a method of wireless communication performed by a mobile device. The method may include performing a first frequency scan for one or more nonstandalone (NSA) -anchor Long Term Evolution (LTE) cells; determining whether a LTE base station is configured as an NSA-anchor LTE cell based on the first frequency scan; and in response to determining that the LTE base station is configured as the NSA-anchor LTE cell, camping on the LTE base station configured as the NSA-anchor LTE cell.

In some aspects, the determining includes comparing results from the first frequency scan to one or more databases. In some aspects, the one or more databases includes at least one of a NSA Fingerprint Database and an NSA Frequency Database. In some aspects, the NSA Fingerprint Database includes NSA-anchor LTE cell information. In some aspects, the NSA-anchor LTE cell information includes historical information about one or more of the following: public land mobile network (PLMN) , LTE carrier frequency, Evolved Universal Terrestrial Radio Access (E-UTRA) Absolute Radio Frequency Channel Number (EARFCN) , Physical Cell Identifiers (PCIs) , Cell Global Identity (CGI) , and cell reselection priority.

In some aspects, the NSA Frequency Database includes frequencies of one or more NSA-anchor LTE cells. In some aspects, the NSA Frequency Database can be pre-configured based on operator network deployment. In some aspects, camping on the LTE base station configured as the NSA-anchor LTE cell includes establishing a wireless connection with the LTE base station configured as the NSA-anchor LTE cell. In some aspects, establishing the wireless connection includes determining if an upperLayerIndication-r15 is set to TRUE; determining if a new radio (NR) Measurement Object is configured; or determining if a NR secondary cell group (SCG) is added through a radio resource control (RRC) Reconfiguration message.

In some aspects, in response to determining that the LTE base station is not configured as the NSA-anchor LTE cell, the method further includes performing a second frequency scan for one or more nearby NSA-anchor LTE cells. In some aspects, the second frequency scan includes information related to one or more legacy LTE cells. In some aspects, the method further includes determining whether a second LTE base station is configured as an NSA-anchor LTE cell based on the second frequency scan; and in response to determining that the second LTE base station is configured an the NSA-anchor LTE cell, camping on the second LTE base station configured as the NSA-anchor LTE cell. In some implementations, the LTE base station and the second LTE base station can be different base stations. In some other implementations, the LTE base station and the second LTE base station can be the same base station.

In some aspects, in response to determining that the second LTE base station is not configured as the NSA-anchor LTE cell, the method further includes camping on the second LTE base station and performing a background search for one or more nearby NSA-anchor LTE cells. In some aspects, the method further includes determining whether a third LTE base station is configured as an NSA-anchor LTE cell based on the background search; and in response to determining that the third LTE base station is configured as the NSA-anchor LTE cell, determining if a system information block (SIB) two (SIB2) message includes an upperLayerIndicator-r15 indicator set to TRUE. In some aspects, the determining includes comparing results from the background search to one or more resources. In some implementations, the LTE base station, the second LTE base station and the third LTE base station can be different base stations. In some other implementations, the LTE base station, the second LTE base station and the third LTE base station can be the same base station.

In some aspects, the one or more resources includes at least one of the NSA Fingerprint Database, the NSA Frequency Database, and a list of possible NSA frequencies configured in SIB5. In some aspects, the performing the background search occurs periodically based on a timer (Tper) . In some aspects, the performing the background search occurs aperiodically. In some aspects, the background search occurs at time T (n) , and then again T (1) = T (short) , ... through T (n) = 10*2^ (n-1) when n>1 minute. In some aspects, the method further includes in response to determining that the SIB2 message includes the upperLayerIndicator-r15 indicator set to TRUE, updating the NSA Fingerprint Database. In some aspects, the method further includes updating one or more configuration parameters to configure the third LTE base station as a high reselection priority NSA-anchor LTE cell. In some aspects, the method further includes performing cell reselection to the third LTE base station configured as the NSA-anchor LTE cell.

Another innovative aspect of the subject matter described in this disclosure can be implemented in a mobile device for wireless communication. The mobile device may include memory and one or more processors operatively coupled to the memory. The memory and the one or more processors may be configured to perform a first frequency scan for one or more NSA-anchor LTE cells; determine whether a LTE base station is configured as an NSA-anchor LTE cell based on the first frequency scan; and in response to determining that the LTE base station is configured as the NSA-anchor LTE cell, camp on the LTE base station configured as the NSA-anchor LTE cell. In some aspects, the mobile device may perform or implement any one or more of the aspects described in connection with the method, above or elsewhere herein.

Another innovative aspect of the subject matter described in this disclosure can be implemented in a non-transitory computer-readable medium. The 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 perform a first frequency scan for one or more NSA-anchor LTE cells; determine whether a LTE base station is configured as an NSA-anchor LTE cell based on the first frequency scan; and in response to determining that the LTE base station is configured as the NSA-anchor LTE cell, camp on the LTE base station configured as the NSA-anchor LTE cell. In some aspects, the non-transitory computer-readable medium may perform or implement any one or more of the aspects described in connection with the method, above or elsewhere herein.

Another innovative aspect of the subject matter described in this disclosure can be implemented in an apparatus for wireless communication. The apparatus may include means for performing a first frequency scan for one or more NSA-anchor LTE cells; means for determining whether a LTE base station is configured as an NSA-anchor LTE cell based on the first frequency scan; and in response to determining that the LTE base station is configured as the NSA-anchor LTE cell, means for camping on the LTE base station configured as the NSA-anchor LTE cell. In some aspects, the apparatus may perform or implement any one or more of the aspects described in connection with the method, above or elsewhere herein.

Aspects generally include a method, apparatus, system, computer program product, non-transitory computer-readable medium, user equipment, base station, wireless communication device, or processing system as substantially described herein with reference to and as illustrated by the accompanying drawings.

Details of one or more implementations of the subject matter described in this disclosure are set forth in the accompanying drawings and the description below. Other features, aspects, and advantages will become apparent from the description, the drawings and the claims. Note that the relative dimensions of the following figures may not be drawn to scale.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 shows a block diagram conceptually illustrating an example of a wireless network.

Figure 2 shows a block diagram conceptually illustrating an example of a base station in communication with a user equipment (UE) in a wireless network.

Figure 3 shows a component block diagram illustrating an example computing system that may be configured to establish a wireless connection with a nonstandalone (NSA) -anchor Long Term Evolution (LTE) cell.

Figure 4 shows a component block diagram of an example software architecture including a radio protocol stack for the user and control planes in wireless communications.

Figure 5 shows a component block diagram illustrating an example system configured to establish a wireless connection with an NSA-anchor LTE cell.

Figure 6 shows an example logical architecture of a distributed radio access network (RAN) .

Figure 7 shows an example physical architecture of a distributed RAN.

Figure 8 shows a diagram illustrating an example New Radio (NR) NSA architecture.

Figures 9A–9C show example process flow diagrams for establishing a wireless connection with an NSA-anchor LTE cell.

Figure 10 shows a diagram illustrating an example process performed, for example, by a mobile device.

Like reference numbers and designations in the various drawings indicate like elements.

DETAILED DESCRIPTION

The following description is directed to certain implementations for the purposes of describing the innovative aspects of this disclosure. However, a person having ordinary skill in the art will readily recognize that the teachings herein can be applied in a multitude of different ways. Some of the examples in this disclosure are based on wireless and wired local area network (LAN) communication according to the Institute of Electrical and Electronics Engineers (IEEE) 802.11 wireless standards, the IEEE 802.3 Ethernet standards, and the IEEE 1901 Powerline communication (PLC) standards. However, the described implementations may be implemented in any device, system or network that is capable of transmitting and receiving radio frequency signals according to any of the wireless communication standards, including any of the IEEE 802.11 standards, the

standard, code division multiple access (CDMA) , frequency division multiple access (FDMA) , time division multiple access (TDMA) , Global System for Mobile communications (GSM) , GSM/General Packet Radio Service (GPRS) , Enhanced Data GSM Environment (EDGE) , Terrestrial Trunked Radio (TETRA) , Wideband-CDMA (W-CDMA) , Evolution Data Optimized (EV-DO) , 1xEV-DO, EV-DO Rev A, EV-DO Rev B, High Speed Packet Access (HSPA) , High Speed Downlink Packet Access (HSDPA) , High Speed Uplink Packet Access (HSUPA) , Evolved High Speed Packet Access (HSPA+) , Long Term Evolution (LTE) , AMPS, or other known signals that are used to communicate within a wireless, cellular or internet of things (IOT) network, such as a system utilizing 3G, 4G or 5G, or further implementations thereof, technology.

5G NR exists in two versions: non-standalone (or nonstandalone, NSA) 5G NR, and standalone (SA) 5G NR. Initial deployments of 5G NR by operators of mobile networks will use the NSA version, in which 5G NR networks are supported by existing 4G/LTE infrastructures. NSA 5G NR primarily focuses on enhanced mobile broadband (eMBB) services, where 5G NR supported mobile devices will use millimeter wave (mmWave) frequencies for increased data capacity, while also using existing 4G/LTE infrastructures for voice communications. SA 5G NR networks will deploy a new end-to-end architecture, i.e., will not use existing 4G/LTE infrastructure, and will use mmWave and sub-GHz frequencies. Moreover, SA 5G NR is expected to use eMBB, ultra-reliable and low latency communication (URLLC) and Massive machine-type communications (mMTC) to provide multi-gigabit data rates with improved efficiency and lower costs.

Such initial NSA deployments use an anchor carrier radio access technology (RAT, such as LTE or NR) and can be implemented to allow the other RAT (i.e., once anchored to an LTE cell, NR can be added later, or vice versa) to be added in dual connectivity mode. Such a dual connectivity mode may be referred to as an Evolved Universal Mobile Telecommunications System Terrestrial Radio Access (E-UTRA) -New Radio (NR) dual connectivity (ENDC) mode. In ENDC mode, an LTE eNB can be configured as the anchor base station, or anchor cell. Due to the potential length of time before full deployment of SA 5G NR, it is expected that NSA-anchor capable cells will likely coexist with legacy LTE cells (i.e., an LTE-only capable cell that does not have 5G capabilities) for a long time in most coverage areas. In coverage areas that have both legacy LTE cells and NSA-anchor capable cells, a user equipment (UE) , such as a mobile device, while looking for a suitable cell to camp on, or otherwise establish a communication link with, may find a legacy LTE cell first. Such an instance may occur, for example, because the legacy LTE cell has a stronger signal energy during cell selection than the NSA-anchor capable cell.

When signal strength and other conditions indicate that a neighbor base station may be better suited for serving the UE, the UE may perform cell reselection to the neighbor base station. Since not all legacy LTE cells are configured as NSA-anchor capable cells, the UE may not be able to reselect from the legacy LTE cell that it is camped on to a neighboring LTE cell with NSA-anchor capabilities (also referred to herein as an NSA-anchor LTE cell) . Furthermore, even if the neighboring LTE cell is configured as an NSA-anchor LTE cell, in some implementations, the legacy LTE cell signal energy may be stronger than the NSA-anchor LTE cell signal energy, and therefore the UE may stay in the legacy LTE cell with stronger signal energy instead of reselecting to the NSA-anchor LTE cell.

Current UE implementations do not distinguish between legacy LTE cells and NSA-anchor LTE cells during frequency scanning upon initial boot-up or when the UE changes coverage areas. Instead, the UE simply ranks the frequency scans based on the signal energy received from each cell. If the UE camps on a legacy LTE cell, such as when the legacy LTE cell’s signal energy is measurably more robust, or when no nearby neighboring NSA-anchor LTE cells have been configured, the UE will remain camped on the legacy LTE cell until a network configuration is sent to trigger a reselection mechanism. Such situations, where the UE is constrained to camping on the legacy LTE cell, may adversely impact user experience, since the user purchased a 5G NR capable mobile device, but is limited to lower throughput 4G/LTE services while camped on the legacy LTE cell.

The techniques described herein relate to apparatuses, methods and systems for increasing the likelihood that a UE camps and wirelessly connects with an NSA-anchor LTE cell. The techniques can be used for optimizing the likelihood that a UE camps and wirelessly connects with an NSA-anchor LTE cell upon initial boot-up (or power up) or when the UE returns to coverage after an out-of-service scenario (or, for example, the UE exiting “airplane mode” ) .

In some implementations, the UE can utilize an NSA Fingerprint Database which can be used to store NSA-anchor LTE cell information, including the most recent NSA-anchor LTE cell the UE was connected with. The NSA-anchor LTE cell information also can include historical information about one or more of the following features associated with one or more NSA-anchor LTE cells, such as public land mobile network (PLMN) information, LTE carrier frequency information, Evolved Universal Terrestrial Radio Access (E-UTRA) Absolute Radio Frequency Channel Number (EARFCN) information, Physical Cell Identifiers (PCIs) information, Cell Global Identity (CGI) information and CGI databases, and cell reselection priority information, etc., in addition to other features that will be readily apparent to a person having ordinary skill in the art. The NSA Fingerprint Database can be presented in a table, and in some implementations, the table can be a static table, such that the NSA Fingerprint Database remains stored in memory of the UE, or on a remote server, even when the UE is powered off. For example, the UE may store the NSA-anchor LTE cell information in a data structure such as a database or another suitable data structure.

In some implementations, the UE can utilize an NSA Frequency Database which contains frequencies of known NSA-anchor LTE cells. The NSA Frequency Database, in some implementations, can be pre-configured by an operator or original equipment manufacturer (OEM) , and set according to the operator’s cell deployment in the network. The UE can be configured to dynamically update the NSA Frequency Database via one or more remote servers, based on the UE’s location. As described throughout, the phrase “based on” does not mean “based only on, ” unless expressly specified otherwise. In other words, the phrase “based on” describes both “based only on” and “based at least on. ”

The techniques also can be used for optimizing the likelihood that a UE camps and wirelessly connects with an NSA-anchor LTE cell during a background search. In some implementations, such as where a UE is camped on a legacy LTE cell, the UE can initiate a background search in an attempt to find an NSA-anchor LTE cell. The background search can include comparing the results of the background search to one or more resources. In some implementations, the one or more resources can include an NSA-anchor LTE cell database, the NSA Fingerprint Database, the NSA Frequency Database, and a list of possible NSA frequencies configured in a system information block (SIB) , such as SIB five (SIB5) , message.

In some implementations, and to reduce power consumption, the background search can be based on one or more background search timers. Upon the UE camping on the legacy LTE cell, a first timer, i.e., NSA_Search_T (short) , can be initiated. Under the constraints of the first timer, the UE can be implemented to engage in the background search every few seconds up to every few minutes, until the first timer expires or reaches a threshold value. In some implementations, the first timer can be configured as a periodic timer (Tper) .

In some implementations, if the UE fails to find an NSA-anchor LTE cell under the constraints of the first timer, a second timer, i.e., NSA_Search_T (long) , can be initiated. Under the constraints of the second timer, the UE can be implemented to engage in the background search every few minutes. In some implementations, if the UE fails to find an NSA-anchor LTE cell, the second timer can be extended a few more minutes (such as double the minutes allocated to searching previously) in an aperiodic manner. In some implementations, the second timer can be represented by an equation, where the background search occurs at time T (n) , and the background search occurs again at T (1) = NSA_Search_T (short) , ... through T (n) = 10*2^ (n-1) , when n>1 minute.

In some implementations, applying the techniques described herein may enable the UE to determine whether a cell reselection trigger has occurred, and in response to determining that the cell reselection trigger has occurred, the UE may perform cell reselection from the legacy LTE cell to the NSA-anchor LTE cell.

Particular implementations of the subject matter described in this disclosure can be implemented to realize one or more of the following potential advantages. Utilizing the techniques described herein may provide a mobile device with a higher likelihood to camp on an NSA-anchor LTE cell. Camping, and connecting to the NSA-anchor LTE cell may result in higher data throughput, and may improve user experience. Moreover, the techniques described herein may improve the operations of a mobile device and a communication network by increasing the capabilities of the communication network to support communications with mobile devices, increasing the communication services available to the mobile device, and decreasing the power consumption of mobile devices while scanning and searching for NSA-anchor LTE cells.

Figure 1 shows a block diagram conceptually illustrating an example of a wireless network 100. The wireless network 100 may be an LTE network or some other wireless network, such as a 5G or NR network. Wireless network 100 may include a number of base stations (BSs) 110 (shown as BS 110a, BS 110b, BS 110c and BS 110d) , a number of user equipments (UEs) 120 (shown as UE 120a, UE 120b, UE 120c, UE 120d and UE 120e) and other network entities. A BS is an entity that communicates with UEs and also may be referred to as a base station, a NR BS, a Node B, a gNB, a 5G node B (NB) , an access point, a transmit receive point (TRP) , or the like. Each BS may provide communication coverage for a particular geographic area. In 3GPP, the term “cell” can refer to a coverage area of a BS, a BS subsystem serving this coverage area, or a combination thereof, depending on the context in which the term is used.

A BS may provide communication coverage for a macro cell, a pico cell, a femto cell, another type of cell, or a combination thereof. A macro cell may cover a relatively large geographic area (for example, several kilometers in radius) and may allow unrestricted access by UEs with service subscription. A pico cell may cover a relatively small geographic area and may allow unrestricted access by UEs with service subscription. A femto cell may cover a relatively small geographic area (for example, a home) and may allow restricted access by UEs having association with the femto cell (for example, UEs in a closed subscriber group (CSG) ) . A BS for a macro cell may be referred to as a macro BS. A BS for a pico cell may be referred to as a pico BS. A BS for a femto cell may be referred to as a femto BS or a home BS. In the example shown in Figure 1, a BS 110a may be a macro BS for a macro cell 102a, a BS 110b may be a pico BS for a pico cell 102b, and a BS 110c may be a femto BS for a femto cell 102c. A BS may support one or multiple (for example, three) cells. The terms “eNB” , “base station” , “NR BS” , “gNB” , “TRP” , “AP” , “node B” , “5G NB” , and “cell” may be used interchangeably herein.

In some examples, a cell may not necessarily be stationary, and the geographic area of the cell may move according to the location of a mobile BS. In some examples, the BSs may be interconnected to one another as well as to one or more other BSs or network nodes (not shown) in the wireless network 100 through various types of backhaul interfaces, such as a direct physical connection, a virtual network, or a combination thereof using any suitable transport network.

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

Wireless network 100 may be a heterogeneous network that includes BSs of different types, for example, 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 a high transmit power level (for example, 5 to 40 Watts) whereas pico BSs, femto BSs, and relay BSs may have lower transmit power levels (for example, 0.1 to 2 Watts) .

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

UEs 120a–120e may be dispersed throughout wireless network 100, and each UE may be stationary or mobile. A UE also may be referred to as an access terminal, a terminal, a mobile station, a subscriber unit, a station, etc. A UE may be a cellular phone (for example, a smart phone) , 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, biometric sensors/devices, wearable devices (smart watches, smart clothing, smart glasses, smart wrist bands, smart jewelry (for example, smart ring, smart bracelet) ) , an entertainment device (for example, a music or video device, or a satellite radio) , a vehicular component or sensor, smart meters/sensors, industrial manufacturing equipment, a global positioning system device, or any other suitable device that is configured to communicate via a wireless or wired medium.

Some UEs may be considered machine-type communication (MTC) or evolved or enhanced machine-type communication (eMTC) UEs. MTC and eMTC UEs include, for example, robots, drones, remote devices, sensors, meters, monitors, location tags, etc., that may communicate with a base station, another device (for example, remote device) , or some other entity. A wireless node may provide, for example, connectivity for or to a network (for example, a wide area network such as Internet or a cellular network) via a wired or wireless communication link. Some UEs may be considered Internet-of-Things (IoT) devices or may be implemented as NB-IoT (narrowband internet of things) devices. Some UEs may be considered a Customer Premises Equipment (CPE) . UEs 120a–120e may be included inside a housing that houses components of UEs, such as processor components, memory components, similar components, or a combination thereof.

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

In some examples, access to the air interface may be scheduled, where a scheduling entity (for example, a base station) allocates resources for communication among some or all devices and equipment within the scheduling entity’s service area or cell. Within the present disclosure, as discussed 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, subordinate entities utilize resources allocated by the scheduling entity.

Base stations are not the only entities that may function as a scheduling entity. That is, in some examples, a UE may function as a scheduling entity, scheduling resources for one or more subordinate entities (for example, one or more other UEs) . In this example, the UE is functioning as a scheduling entity, and other UEs utilize resources scheduled by the UE for wireless communication. A UE may function as a scheduling entity in a peer-to-peer (P2P) network, in a mesh network, or another type of network. In a mesh network example, UEs may optionally communicate directly with one another in addition to communicating with the scheduling entity.

Thus, in a wireless communication network with a scheduled access to time–frequency resources and having a cellular configuration, a P2P configuration, and a mesh configuration, a scheduling entity and one or more subordinate entities may communicate utilizing the scheduled resources.

In some aspects, two or more UEs 120 (for example, shown as UE 120a and UE 120e) may communicate directly using one or more sidelink channels (for example, without using a base station 110 as an intermediary to communicate with one another) . For example, the UEs 120a–120e may communicate using peer-to-peer (P2P) communications, device-to-device (D2D) communications, a vehicle-to-everything (V2X) protocol (which may include a vehicle-to-vehicle (V2V) protocol, a vehicle-to-infrastructure (V2I) protocol, or similar protocol) , a mesh network, or similar networks, or combinations thereof. In this case, the UEs 120a–120e may perform scheduling operations, resource selection operations, as well as other operations described elsewhere herein as being performed by the BSs 110a–110d.

Figure 2 shows a block diagram conceptually illustrating an example 200 of a base station 110 in communication with a UE 120. In some aspects, the base station 110 and the UE 120 may respectively be one of the base stations and one of the UEs in the wireless network 100 of Figure 1, such as BSs 110a–110d and UEs 120a–120e. The base station 110 may be equipped with T antennas 234a through 234t, and the UE 120 may be equipped with R antennas 252a through 252r, where in general T ≥ 1 and R ≥ 1.

At base station 110, a transmit processor 220 may receive data from a data source 212 for one or more UEs, select one or more modulation and coding schemes (MCS) for each UE based at least in part on channel quality indicators (CQIs) received from the UE, process (for example, encode and modulate) the data for each UE based at least in part on the MCS (s) selected for the UE, and provide data symbols for all UEs. The transmit processor 220 also may process system information (for example, for semi-static resource partitioning information (SRPI) , etc. ) and control information (for example, CQI requests, grants, upper layer signaling, etc. ) and provide overhead symbols and control symbols. The transmit processor 220 also may generate reference symbols for reference signals (for example, the cell-specific reference signal (CRS) ) and synchronization signals (for example, the primary synchronization signal (PSS) and secondary synchronization signal (SSS) ) . A transmit (TX) multiple-input multiple-output (MIMO) processor 230 may perform spatial processing (for example, precoding) on the data symbols, the control symbols, the overhead symbols, or the 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 (for example, for OFDM, etc. ) to obtain an output sample stream. Each modulator 232 may further process (for example, convert to analog, amplify, filter, and upconvert) the output sample stream to obtain a downlink signal. 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, the synchronization signals can be generated with location encoding to convey additional information.

At UE 120, antennas 252a through 252r may receive the downlink signals from base station 110 or other base stations and may provide received signals to demodulators (DEMODs) 254a through 254r, respectively. Each demodulator 254 may condition (for example, filter, amplify, downconvert, and digitize) a received signal to obtain input samples. Each demodulator 254 may further process the input samples (for example, 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 (for example, demodulate and decode) the detected symbols, provide decoded data for UE 120 to a data sink 260, and provide decoded control information and system information to a controller or processor (controller/processor) 280. A channel processor may determine reference signal received power (RSRP) , received signal strength indicator (RSSI) , reference signal received quality (RSRQ) , channel quality indicator (CQI) , etc. In some aspects, one or more components of UE 120 may be included in a housing.

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

In some telecommunications (for example, NR) , the base station 110 may transmit synchronization signals. For example, the base station 110 may transmit a primary synchronization signal (PSS) , a secondary synchronization signal (SSS) , or the like, on the downlink for each cell supported by the base station 110. The PSS and SSS may be used by the UE 120 for cell search and acquisition. For example, the PSS may be used by the UE 120 to determine symbol timing, and the SSS may be used by the UE 120 to determine a physical cell identifier, associated with the base station 110, and frame timing. The base station 110 also may transmit a physical broadcast channel (PBCH) . The PBCH may carry some system information, such as system information that supports initial access by UEs.

The base station 110 also may transmit system information, such as system information blocks (SIBs) on a physical downlink shared channel (PDSCH) in certain slots. The base station 110 may transmit control information/data on a physical downlink control channel (PDCCH) in select symbol periods of a slot, which also may be configurable for each slot. The base station 110 may transmit traffic data or other data on the PDSCH in the remaining symbol periods of each slot.

The controller/processor 240 of base station 110, the controller/processor 280 of UE 120, or any other component (s) of Figure 2 may perform one or more techniques associated with establishing wireless connections with nonstandalone (NSA) -anchor Long Term Evolution (LTE) cells, as described in more detail elsewhere herein. For example, the controller/processor 240 of base station 110, the controller/processor 280 of UE 120, or any other component (s) (or combinations of components) of Figure 2 may perform or direct operations of, for example, the process 1000 of Figure 10 or other processes as described herein. The

memories

242 and 282 may store data and program codes for base station 110 and UE 120, respectively. A scheduler 246 may schedule UEs for data transmission on the downlink, the uplink, or a combination thereof.

The stored program codes, when executed by the controller/processor 280 or other processors and modules at UE 120, may cause the UE 120 to perform operations described with respect to the process 1000 of Figure 10, or other processes as described herein. The stored program codes, when executed by the controller/processor 240 or other processors and modules at base station 110, may cause the base station 110 to perform operations described with respect to the process 1000 of Figure 10 or other processes as described herein. A scheduler 246 may schedule UEs for data transmission on the downlink, the uplink, or a combination thereof.

In some aspects, UE 120 may include means for performing a first frequency scan for one or more NSA-anchor LTE cells, means for determining whether a LTE base station is configured as an NSA-anchor LTE cell based on the first frequency scan, means for, in response to determining that the LTE base station is configured as the NSA-anchor LTE cell, camping on the LTE base station configured as the NSA-anchor LTE cell, or the like, or combinations thereof. In some aspects, such means may include one or more components of UE 120 described in connection with Figure 2.

While blocks in Figure 2 are illustrated as distinct components, the functions described above with respect to the blocks may be implemented in a single hardware, software, or combination component or in various combinations of components. For example, the functions described with respect to the transmit processor 264, the receive processor 258, the TX MIMO processor 266, or another processor may be performed by or under the control of controller/processor 280.

Figure 3 shows a component block diagram illustrating an example computing system that may be configured to implement management of cell selection. Some implementations may be implemented on a number of single processor and multiprocessor computer systems, including a system-on-chip (SOC) or system in a package (SIP) . The example illustrated in Figure 3 is a SIP 300 architecture that may be used in wireless devices implementing some implementations.

The illustrated example SIP 300 includes a two

SOCs

302, 304, a clock 306, and a voltage regulator 308. In some implementations, the first SOC 302 may operate as central processing unit (CPU) of the wireless device that carries out the instructions of software application programs by performing the arithmetic, logical, control and input/output (I/O) operations specified by the instructions. In some implementations, the second SOC 304 may operate as a specialized processing unit. For example, the second SOC 304 may operate as a specialized 5G processing unit responsible for managing high volume, high speed (such as 5 Gbps, etc. ) , or very high frequency short wave length (such as 28 GHz mmWave spectrum, etc. ) communications.

The first SOC 302 may include a digital signal processor (DSP) 310, a modem processor 312, a graphics processor 314, an application processor 316, one or more coprocessors 318 (such as vector co-processor) connected to one or more of the processors, memory 320, custom circuity 322, system components and resources 324, an interconnection/bus module 326, one or more temperature sensors 330, a thermal management unit 332, and a thermal power envelope (TPE) component 334. The second SOC 304 may include a 5G modem processor 352, a power management unit 354, an interconnection/bus module 364, a plurality of mmWave transceivers 356, memory 358, and various additional processors 360, such as an applications processor, packet processor, etc.

Each

processor

310, 312, 314, 316, 318, 352, 360 may include one or more cores, and each processor/core may perform operations independent of the other processors/cores. For example, the first SOC 302 may include a processor that executes a first type of operating system (such as FreeBSD, LINUX, OS X, etc. ) and a processor that executes a second type of operating system (such as MICROSOFT WINDOWS 10) . In addition, any or all of the

processors

310, 312, 314, 316, 318, 352, 360 may be included as part of a processor cluster architecture (such as a synchronous processor cluster architecture, an asynchronous or heterogeneous processor cluster architecture, etc. ) .

The first and

second SOCs

302, 304 may include various system components, resources and custom circuitry for managing sensor data, analog-to-digital conversions, wireless data transmissions, and for performing other specialized operations, such as decoding data packets and processing encoded audio and video signals for rendering in a web browser. For example, the system components and resources 324 of the first SOC 302 may include power amplifiers, voltage regulators, oscillators, phase-locked loops, peripheral bridges, data controllers, memory controllers, system controllers, access ports, timers, and other similar components used to support the processors and software clients running on a wireless device. The system components and resources 324 or custom circuitry 322 also may include circuitry to interface with peripheral devices, such as cameras, electronic displays, wireless communication devices, external memory chips, etc.

The first and

second SOCs

302, 304 may communicate via interconnection/bus module 350. The

various processors

310, 312, 314, 316, 318, may be interconnected to one or more memory elements 320, system components and resources 324, and custom circuitry 322, and a thermal management unit 332 via an interconnection/bus module 326. Similarly, the modem processor 352 may be interconnected to the power management unit 354, the mmWave transceivers 356, memory 358, and various additional processors 360 via the interconnection/bus module 364. The interconnection/

bus module

326, 350, 364 may include an array of reconfigurable logic gates or implement a bus architecture (such as CoreConnect, AMBA, etc. ) . Communications may be provided by advanced interconnects, such as high-performance networks-on chip (NoCs) .

The first or

second SOCs

302, 304 may further include an input/output module (not illustrated) for communicating with resources external to the SOC, such as a clock 306 and a voltage regulator 308. Resources external to the SOC (such as clock 306, voltage regulator 308) may be shared by two or more of the internal SOC processors/cores.

In addition to the example SIP 300 discussed above, some implementations may be implemented in a wide variety of computing systems, which may include a single processor, multiple processors, multicore processors, or any combination thereof.

Figure 4 shows a component block diagram of an example of a software architecture 400 including a radio protocol stack for the user and control planes in wireless communications. The software architecture 400 including a radio protocol stack for the user and control planes in wireless communications between a base station 450 (such as the BSs 110a–110d depicted and described in Figure 1, or the base station 110 depicted and described in Figure 2) and a wireless device 420 (such as the UEs 120a–120e depicted and described in Figure 1, or the wireless device 120 depicted and described in Figure 2) . With reference to Figures 1–4, the wireless device 420 may implement the software architecture 400 to communicate with the base station 450 of a communication system (such as the wireless network 100 depicted and described in Figure 1) . In some implementations, layers in software architecture 400 may form logical connections with corresponding layers in software of the base station 450. The software architecture 400 may be distributed among one or more processors (such as the

processors

312, 314, 316, 318, 352, 360 depicted and described in Figure 3) . While illustrated with respect to one radio protocol stack, in a multi-SIM (subscriber identity module) wireless device, the software architecture 400 may include multiple protocol stacks, each of which may be associated with a different SIM (such as two protocol stacks associated with two SIMs, respectively, in a dual-SIM wireless communication device) . While described below with reference to LTE communication layers, the software architecture 400 may support any of variety of standards and protocols for wireless communications, or may include additional protocol stacks that support any of variety of standards and protocols wireless communications.

The software architecture 400 may include a Non-Access Stratum (NAS) 402 and an Access Stratum (AS) 404. The NAS 402 may include functions and protocols to support packet filtering, security management, mobility control, session management, and traffic and signaling between a SIM (s) of the wireless device and its core network. The AS 404 may include functions and protocols that support communication between a SIM (s) and entities of supported access networks (such as a base station) . In particular, the AS 404 may include at least three layers (Layer 1, Layer 2, and Layer 3) , each of which may contain various sub-layers.

In the user and control planes, Layer 1 (L1) of the AS 404 may be a physical layer (PHY) 406, which may oversee functions that enable transmission or reception over the air interface. Examples of such physical layer 406 functions may include cyclic redundancy check (CRC) attachment, coding blocks, scrambling and descrambling, modulation and demodulation, signal measurements, MIMO, etc. The physical layer may include various logical channels, including the Physical Downlink Control Channel (PDCCH) and the Physical Downlink Shared Channel (PDSCH) .

In the user and control planes, Layer 2 (L2) of the AS 404 may be responsible for the link between the wireless device 420 and the base station 450 over the physical layer 406. In some implementations, Layer 2 may include a media access control (MAC) sublayer 408, a radio link control (RLC) sublayer 410, and a packet data convergence protocol (PDCP) 412 sublayer, each of which form logical connections terminating at the base station 450.

In the control plane, Layer 3 (L3) of the AS 404 may include a radio resource control (RRC) sublayer 413. While not shown, the software architecture 400 may include additional Layer 3 sublayers, as well as various upper layers above Layer 3. In some implementations, the RRC sublayer 413 may provide functions including broadcasting system information, paging, and establishing and releasing an RRC signaling connection between the wireless device 420 and the base station 450.

In some implementations, the PDCP sublayer 412 may provide uplink functions including multiplexing between different radio bearers and logical channels, sequence number addition, handover data handling, integrity protection, ciphering, and header compression. In the downlink, the PDCP sublayer 412 may provide functions that include in-sequence delivery of data packets, duplicate data packet detection, integrity validation, deciphering, and header decompression.

In the uplink, the RLC sublayer 410 may provide segmentation and concatenation of upper layer data packets, retransmission of lost data packets, and Automatic Repeat Request (ARQ) . In the downlink, while the RLC sublayer 410 functions may include reordering of data packets to compensate for out-of-order reception, reassembly of upper layer data packets, and ARQ.

In the uplink, MAC sublayer 408 may provide functions including multiplexing between logical and transport channels, random access procedure, logical channel priority, and hybrid-ARQ (HARQ) operations. In the downlink, the MAC layer functions may include channel mapping within a cell, de-multiplexing, discontinuous reception (DRX) , and HARQ operations.

While the software architecture 400 may provide functions to transmit data through physical media, the software architecture 400 may further include at least one host layer 414 to provide data transfer services to various applications in the wireless device 420. In some implementations, application-specific functions provided by the at least one host layer 414 may provide an interface between the software architecture and the general purpose processor.

In some other implementations, the software architecture 400 may include one or more higher logical layer (such as transport, session, presentation, application, etc. ) that provide host layer functions. For example, in some implementations, the software architecture 400 may include a network layer (such as IP layer) in which a logical connection terminates at a packet data network (PDN) gateway (PGW) . In some implementations, the software architecture 400 may include an application layer in which a logical connection terminates at another device (such as end user device, server, etc. ) . In some implementations, the software architecture 400 may further include in the AS 404 a hardware interface 416 between the physical layer 406 and the communication hardware (such as one or more radio frequency (RF) transceivers) .

Figure 5 shows a component block diagram illustrating an example system 500 configured to establish a wireless connection with an NSA-anchor LTE cell. The system 500 may be performed by a processor of a mobile device. In some implementations, the system 500 may include one or more computing platforms 502 or one or more remote platforms 504. With reference to Figures 1–5, the computing platform (s) 502 may include a wireless device (such as the UEs 120a–120e depicted and described in Figure 1, or the UE 120 depicted and described in Figure 2, or the wireless device 420 depicted and described in Figure 4) . The remote platform (s) 504 may include one or more servers configured to store data related to, and dynamically update, one or more NSA-anchor LTE cell-related databases. The one or more NSA-anchor LTE cell-related databases can include the NSA Frequency Database.

The computing platform (s) 502 may be configured by machine-readable instructions 506. The machine-readable instructions 506 may include one or more instruction modules. The instruction modules may include computer program modules. The instruction modules may include one or more of a Frequency Scanning Module 508, a NSA-Anchor LTE Cell Detection Module 510, a Cell Camping Module 512, a Comparison Module 514, a Wireless Connection Establishment Module 516, a Background Searching Module 518, a System Information Block (SIB) Detection Module 520, a Cell Reselection Performance Module 522, an Updating Module 524, in addition to other such instruction modules.

The Frequency Scanning Module 508 may be configured to perform one or more frequency scans for one or more NSA-anchor LTE cells.

The NSA-Anchor LTE Cell Detection Module 510 may be configured to determine whether one or more LTE base stations include, or are configured with, NSA-anchor LTE cell capabilities. In some implementations, determining whether the one or more LTE base stations are configured as an NSA-anchor LTE cell is based on the one or more frequency scans performed by the Frequency Scanning Module 508.

The Cell Camping Module 512 may be configured to camp on an LTE base station configured as a NSA-anchor LTE cell. In some implementations, the Cell Camping Module 512 may be configured to camp on the LTE base station configured as the NSA-anchor LTE cell in response to the NSA-anchor LTE cell detection module determining that the LTE base station is configured as the NSA-anchor LTE cell.

The Comparison Module 514 may be configured to compare the results of one or more frequency scans performed by the Frequency Scanning Module 508 to one or more databases. In some implementations, the Comparison Module 514 may be configured to compare the results of one or more background searches performed by the Background Searching Module 518 to one or more resources.

The Wireless Connection Establishment Module 516 may be configured to establish a wireless connection with a legacy LTE base station, or an NSA-anchor LTE cell. In some implementations, the Wireless Connection Establishment Module 516 may be configured to establish a wireless connection with the NSA-anchor LTE cell after determining that an upperLayerIndication-r15 indicator is set to TRUE. The upperLayerIndication-r15 indicator is an indication to upper layers that the wireless device has entered a coverage area that offers 5G NR capabilities. In some implementations, the Wireless Connection Establishment Module 516 may be configured to establish a wireless connection with the NSA-anchor LTE cell after determining that a NR Measurement Object is configured. In some implementations, the Wireless Connection Establishment Module 516 may be configured to establish a wireless connection with the NSA-anchor LTE cell after determining that an NR secondary cell group (SCG) has been added through a radio resource control (RRC) Reconfiguration message.

The Background Searching Module 518 may be configured to perform one or more background searches for one or more NSA-anchor LTE cells.

The SIB Detection Module 520 may be configured to determine whether a SIB2 message includes an upperLayerIndicator-r15 indicator set to TRUE.

The Cell Reselection Performance Module 522 may be configured to perform cell reselection from an LTE base station, such as a legacy LTE cell, to an NSA-anchor LTE cell.

The Updating Module 524 may be configured to update one or more configuration parameters related to an LTE base station that is configured as an NSA-anchor LTE cell. In some implementations, the one or more configuration parameters may include identifying the LTE base station as a high selection priority NSA-anchor LTE cell. In some implementations, the Updating Module 524 may be configured to update one or more databases, such as an NSA Fingerprint Database. In such implementations, the Updating Module 524 may update the NSA Fingerprint Database in response to the SIB Detection Module 520 determining that the SIB2 message includes an upperLayerIndicator-r15 indicator set to TRUE.

Figure 6 shows an example logical architecture of a distributed RAN 600. A 5G access node 606 may include an access node controller (ANC) 602. The ANC may be a central unit (CU) of the distributed RAN 600. The backhaul interface to the next generation core network (NG-CN) 604 may terminate at the ANC. The backhaul interface to neighboring next generation access nodes (NG-ANs) may terminate at the ANC. The ANC may include one or more TRPs 608 (which also may be referred to as BSs, NR BSs, Node Bs, 5G NBs, APs, gNB, or some other term) . As described above, a TRP may be used interchangeably with “cell. ”

The TRPs 608 may be a distributed unit (DU) . The TRPs may be connected to one ANC (ANC 602) or more than one ANC (not illustrated) . For example, for RAN sharing, radio as a service (RaaS) , and service specific AND deployments, the TRP may be connected to more than one ANC. A TRP may include one or more antenna ports. The TRPs may be configured to individually (for example, dynamic selection) or jointly (for example, joint transmission) serve traffic to a UE.

The local architecture of RAN 600 may be used to illustrate fronthaul definition. The architecture may be defined that support fronthauling solutions across different deployment types. For example, the architecture may be based at least in part on transmit network capabilities (for example, bandwidth, latency, jitter, etc. ) .

The architecture may share features or components with LTE. According to aspects, the next generation AN (NG-AN) 610 may support dual connectivity with NR. The NG-AN may share a common fronthaul for LTE and NR.

The architecture may enable cooperation between and among TRPs 608. For example, cooperation may be preset within a TRP or across TRPs via the ANC 602. According to aspects, no inter-TRP interface may be needed/present.

According to aspects, a dynamic configuration of split logical functions may be present within the architecture of RAN 600. The packet data convergence protocol (PDCP) , radio link control (RLC) , medium access control (MAC) protocol may be adaptably placed at the ANC or TRP.

According to various aspects, a BS may include a central unit (CU) (for example, ANC 602) or one or more distributed units (for example, one or more TRPs 608) .

Figure 7 shows an example physical architecture of a distributed RAN 700. A centralized core network unit (C-CU) 702 may host core network functions. The C-CU may be centrally deployed. C-CU functionality may be offloaded (for example, to advanced wireless services (AWS) ) , in an effort to handle peak capacity.

A centralized RAN unit (C-RU) 704 may host one or more ANC functions. Optionally, the C-RU may host core network functions locally. The C-RU may have distributed deployment. The C-RU may be closer to the network edge.

A distributed unit (DU) 706 may host one or more TRPs. The DU may be located at edges of the network with radio frequency (RF) functionality.

Figure 8 shows a diagram illustrating an example New Radio non-standalone (NSA) architecture 800. In some implementations, this NSA architecture 800 may be referred to as an Option 3a architecture. As shown in Figure 8, in a New Radio (NR) or 5G NSA mode, a UE 120 (such as the UEs 120a–120e depicted and described in Figure 1, or the UE 120 depicted and described in Figure 2, or the wireless device 420 depicted and described in Figure 4) may communicate with both an eNB or MeNB (such as a 4G base station, which may be enabled by the BSs 110a–110d depicted and described in Figure 1, or the BS 110 depicted and described in Figure 2, or the base station 450 depicted and described in Figure 4) and a gNB or SgNB (such as a 5G base station, which may be enabled by the BSs 110a–110d depicted and described in Figure 1, or the BS 110 depicted and described in Figure 2, or the base station 450 depicted and described in Figure 4) .

The MeNB and the SgNB may communicate directly or indirectly with a 4G/LTE core network, which is shown, for example, as an evolved packet core (EPC) that includes a mobility management entity (MME) , a packet data network (PDN) gateway (PGW) , and a serving gateway (SGW) . The MeNB and SgNB can communicate over an X2 interface. In Figure 8, the PGW and the SGW are shown collectively as P/SGW. In some aspects, the MeNB and the SgNB may be co-located at the same base station. In some aspects, the MeNB and the SgNB may be included in different base stations. For example, the MeNB and the SgNB may not be co-located.

As further shown in Figure 8, in some aspects, a wireless network that permits operation in a 5G NSA mode may permit such operations using a master cell group (MCG) for a first RAT (such as an LTE RAT or a 4G RAT) and a secondary cell group (SCG) for a second RAT (such as an NR RAT or a 5G RAT) . In this case, the UE 120 may communicate with the MeNB via the MCG bearer 805, and may communicate with the SgNB via the SCG bearer 810. In some aspects, the MCG may anchor a network connection between the UE 120 and the 4G/LTE core network (such as for mobility, coverage, or control plane information) , and the SCG may be added as additional carriers to increase throughput (such as for data traffic or user plane information) . In some aspects, the SgNB and the MeNB may not transfer user plane information between one another.

In some aspects, the 5G NSA mode may be referred to as an Evolved Universal Mobile Telecommunications System Terrestrial Radio Access (E-UTRA) -New Radio (NR) dual connectivity (ENDC) mode. In some aspects, the UE 120 operating in the ENDC mode, having dual connectivity with an LTE base station (such as an MeNB) and an NR base station (such as a SgNB) , may be referred to as an ENDC UE. Although some operations are described herein in connection with an ENDC mode, these operations may be performed in connection with any type of dual connectivity mode, referred to generally as multi-radio dual connectivity (MRDC) . The dual connectivity configuration illustrated in Figure 8 supports NSA 5G network access by 5G capable UEs, where in NSA operation the EPC controls the wireless communications.

Figures 9A–9C show example process flow diagrams 900a–900c for establishing a wireless connection with an NSA-anchor LTE cell. The operations of the process flow diagrams 900a–900c may be implemented by a UE, such as any of the UEs 120a-120e depicted and described in Figure 1, the UE 120 depicted and described in Figure 2, the wireless device 420 depicted and described in Figure 4, and the UE 120 depicted and described in Figure 8. Additionally, the operations of the process flow diagrams 900a–900c may be implemented by a processor of the UE, such as the processor 536 depicted and described in Figure 5, or other such components described throughout this disclosure.

In some implementations, the UEs 120a–120e, the UE 120, the wireless device 420, the UE 120, the processor 536, or another component of the UE, may execute a set of codes to control the functional elements of the respective device, or of one or more other devices, to perform the functions described in Figures 9A–9C. Additionally, or alternatively, the UEs 120a–120e, the UE 120, the wireless device 420, the UE 120, the processor 536, or another component of the UE, may perform aspects of the functions described in Figures 9A–9C using special-purpose hardware.

As depicted in the process flow diagram 900a in Figure 9A, at block 902, a first frequency scan can be performed. The first frequency scan can be performed after the UE initiates a boot up, or power on process, or when the UE returns to a coverage area from an out-of-service scenario, exits airplane mode, or otherwise initiates or changes a connection in the wireless communication network. The UE, a processor of the UE, or another component of the UE, can perform the first frequency scan in search of one or more legacy LTE cells or one or more NSA-anchor LTE cells. For example, the first frequency scan can be performed by the Frequency Scanning Module 508, depicted and described in Figure 5.

At block 904, results of the first frequency scan can be compared to one or more NSA-anchor LTE cell-related databases. The NSA-anchor LTE cell-related databases can include an NSA Fingerprint Database and an NSA Frequency Database, as described throughout. In some implementations, the UE, a processor of the UE, or another component of the UE, can compare the results of the first frequency scan to the NSA Fingerprint Database, which is configured to store information, including historical information, about known NSA-anchor LTE cells. In some implementations, the UE, a processor of the UE, or another component of the UE, can compare the results of the first frequency scan to the NSA Frequency Database, which is configured to store known frequencies of NSA-anchor LTE cells. For example, comparing the results of the first frequency scan to the NSA Fingerprint Database or the NSA Frequency Database can be performed by the Comparison Module 514, depicted and described in Figure 5. In some implementations, the results of the first frequency scan can be compared to the NSA Fingerprint Database first, before the results of the first frequency scan are compared to the NSA Frequency Database. In some other implementations, the results of the first frequency scan can be compared to both the NSA Fingerprint Database and NSA Frequency Database concurrently.

In some implementations, the one or more NSA-anchor LTE cell-related databases can be created by the UE, a processor of the UE, or another component of the UE. For example, logic of the UE (such as the controller/processor 280, depicted and described in Figure 2, operating under control of control information or an instruction set defining the requisite functions) may create a database structure in a memory thereof (such as the memory 282, depicted and described in Figure 2, or the electronic storage 534, depicted and described in Figure 5) for storing information (such as PLMN, EARFCN, PCI, CGI, etc. ) related to areas and cells having NSA mode support. As the UE changes location or coverage area, the UE, a processor of the UE, or another component of the UE, can be implemented to update the one or more NSA-anchor LTE cell-related databases. For example, updating the one or more NSA-anchor LTE cell-related databases can be performed by the Updating Module 524, depicted and described in Figure 5.

At determination block 906, the UE, a processor of the UE, or another component of the UE, can determine whether any nearby, adjacent or neighboring, LTE base stations are configured as an NSA-anchor LTE cell. The determination can be based on the first frequency scan and comparing the results of the first frequency scan to the one or more NSA-anchor LTE cell-related databases. For example, the determination can be performed by the NSA-Anchor LTE Cell Detection Module 510, depicted and described in Figure 5.

The term “determine” or “determining” encompasses a wide variety of actions and, therefore, “determining” can include calculating, computing, processing, deriving, investigating, looking up (such as via looking up in a table, a database or another data structure) , ascertaining and the like. Also, “determining” can include receiving (such as receiving information) , accessing (such as accessing data in a memory) and the like. Also, “determining” can include resolving, selecting, choosing, establishing and other such similar actions.

If it is determined that the results of the first frequency scan indicate (i.e., determination block 906 = “Yes” ) that a nearby LTE base station may be configured as an NSA-anchor LTE cell based on the comparison to the NSA Fingerprint Database, to the NSA Frequency Database, or both, at block 908, the UE, a processor of the UE, or another component of the UE, can be configured to camp on the LTE base station configured as the NSA-anchor LTE cell. For example, the process of camping on the LTE base station configured as the NSA-anchor LTE cell can be performed by the Cell Camping Module 512, depicted and described in Figure 5.

In some implementations, camping on the LTE base station configured as the NSA-anchor LTE cell includes establishing a wireless connection with the LTE base station configured as the NSA-anchor LTE cell. For example, establishing the wireless connection can be performed by the Wireless Connection Establishment Module 516, depicted and described in Figure 5. In some implementations, establishing the wireless connection includes determining if an upperLayerIndication-r15 indicator is set to TRUE, or determining if a NR Measurement Object has been configured, or determining if a NR SCG has been added through a RRC Reconfiguration message.

Conversely, if it is determined that the results of the first frequency scan do not indicate (i.e., determination block 906 = “No” ) that any nearby LTE base stations are configured as an NSA-anchor LTE cell based on the comparison to the NSA Fingerprint Database, to the NSA Frequency Database, or both, the process flow will continue to the process flow diagram 900b in Figure 9B at block 910.

As depicted in the process flow diagram 900b in Figure 9B, at block 910, a second frequency scan can be performed. The second frequency scan can be performed after the UE, a processor of the UE, or another component of the UE, determines that no nearby LTE base stations are configured as NSA-anchor LTE cells. The UE, a processor of the UE, or another component of the UE, can perform the second frequency scan in search of one or more NSA-anchor LTE cells, or in search of one or more legacy LTE cells, or both. For example, the second frequency scan can be performed by the Frequency Scanning Module 508, depicted and described in Figure 5.

In some implementations, results of the second frequency scan can be compared to one or more legacy LTE cell-related databases. The legacy LTE cell-related databases can include any databases known to a person having ordinary skill in the art that include stored information, including LTE frequencies and bands, about known legacy LTE cells. The stored information can include PLMN information, EARFCN information, frequency band information, bandwidth information, and PCI information, in addition to other such types of information. In some implementations, the UE, a processor of the UE, or another component of the UE, can compare the results of the second frequency scan to the legacy LTE cell-related databases. For example, comparing the results of the second frequency scan to the legacy LTE cell-related databases can be performed by the Comparison Module 514, depicted and described in Figure 5. In some optional implementations, the results of the second frequency scan can again be compared to one or more NSA-anchor LTE cell-related databases, such as the NSA Fingerprint Database or the NSA Frequency Database.

At determination block 914, the UE, a processor of the UE, or another component of the UE, can be configured to receive an SIB2 message from a base station, and can determine whether the SIB2 message includes an upperLayerIndicator-r15 indicator set to TRUE. For example, checking whether the SIB2 message includes an upperLayerIndicator-r15 indicator set to TRUE can be performed by either the SIB Detection Module 520 or the Wireless Connection Establishment Module 516, depicted and described in Figure 5..

If it is determined that the upperLayerIndicator-r15 indicator is set to TRUE (i.e., determination block 914 = “Yes” ) at block 916, the UE, a processor of the UE, or another component of the UE, can be configured to camp on the LTE base station configured as the NSA-anchor LTE cell. For example, the process of camping on the LTE base station configured as the NSA-anchor LTE cell can be performed by the Cell Camping Module 512, depicted and described in Figure 5. Additionally, or alternatively, the process of camping on the LTE base station configured as the NSA-anchor LTE cell can be performed by the Wireless Connection Establishment Module 516. In some implementations, if the upperLayerIndicator-r15 indicator is set to TRUE, the process flow can continue in the process flow diagram 900c in Figure 9C at block 928.

Conversely, if it is determined that the upperLayerIndicator-r15 indicator is not set to TRUE (i.e., determination block 914 = “No” ) the process flow will continue to the process flow diagram 900c in Figure 9C at block 918. Determining that the upperLayerIndicator-r15 is not set to TRUE can be performed by either the SIB Detection Module 520 or the Wireless Connection Establishment Module 516, depicted and described in Figure 5.

As depicted in the process flow diagram 900c in Figure 9C, at block 918, the UE, a processor of the UE, or another component of the UE, can be configured to camp on a legacy LTE base station. For example, the process of camping on the LTE base station configured as the NSA-anchor LTE cell can be performed by the Cell Camping Module 512, depicted and described in Figure 5. Although the UE may prefer to camp on an NSA-anchor LTE cell, as it may obtain very high throughput via the 5G NR SCG connection, by camping on a legacy LTE base station (i.e., a cell providing only LTE services, and not 5G NR services) instead of camping on a GSM cell or W-CDMA cell, the UE may still obtain high throughput and improved data rates.

At block 920, a background search can be performed. The background search can be performed using one or more resources. The one or more resources can be used to detect or determine frequency information associated with one or more nearby or neighboring cells. The one or more resources can include any of the following, but is not limited to: one or more NSA-anchor LTE cell-related databases, such as the NSA Fingerprint Database and the NSA Frequency Database, in addition to a list of possible NSA-anchor LTE cell frequencies provided in, for example, a system information block (SIB) five (SIB5) message. The background search can be performed after the UE, a processor of the UE, or another component of the UE, determines that no nearby LTE base stations are configured as NSA-anchor LTE cells. The background search also can be performed once the UE has camped on a legacy LTE base station. The UE, a processor of the UE, or another component of the UE, can perform the background search in search of one or more NSA-anchor LTE cells. For example, the background search can be performed by the Background Searching Module 518, depicted and described in Figure 5.

At block 922, results of the background search can be compared to the one or more resources. Again, the one or more resources can include any of the following, but is not limited to: one or more NSA-anchor LTE cell-related databases, such as the NSA Fingerprint Database and the NSA Frequency Database, in addition to a list of possible NSA-anchor LTE cell frequencies provided in, for example, a system information block (SIB) five (SIB5) message. For example, in implementations in which an NSA-anchor LTE cell is deployed in specific LTE frequency bands, a mobile network operator can be implemented to deploy the NSA-anchor LTE cell in LTE frequency band 3, or band 39. As such, the UE, a processor of the UE, or another component of the UE, can be implemented to consider that band 3 or band 39 frequencies configured in a SIB5 message within the particular mobile network are possible frequencies for an NSA-anchor LTE cell. Comparing the results of the background search to the one or more resources can be performed by, for example, the Comparison Module 514, depicted and described in Figure 5.

At determination block 924, the UE, a processor of the UE, or another component of the UE, can determine whether any nearby, adjacent or neighboring, LTE base stations are configured as an NSA-anchor LTE cell. The determination can be based on the background search and comparing the results of the background search to the one or more resources. For example, the determination can be performed by the NSA-Anchor LTE Cell Detection Module 510, depicted and described in Figure 5.

If it is determined that the results of the background search indicate (i.e., determination block 924 = “Yes” ) that a nearby LTE base station may be configured as an NSA-anchor LTE cell based on the comparison to the one or more resources, the process flow diagram 900c may proceed to block 928, discussed further below.

Conversely, if it is determined that the results of the background search do not indicate (i.e., determination block 924 = “No” ) that any nearby LTE base stations are configured as an NSA-anchor LTE cell based on the comparison to the one or more resources, the process flow diagram 900c may proceed to determination block 926.

At determination block 926, the UE, a processor of the UE, or another component of the UE, can determine whether an SIB2 message includes an upperLayerIndicator-r15 indicator set to TRUE. The determination can include receiving the SIB2 message and evaluating the upperLayerIndicator-r15 indicator. For example, the determination can be performed by the SIB Detection Module 520, depicted and described in Figure 5.

If it is determined that the SIB2 message include the upperLayerIndicator-r15 indicator and it is set to TRUE (i.e., determination block 926 = “Yes” ) , at block 928, the UE, a processor of the UE, or another component of the UE, can be configured to update one or more configuration parameters to increase the chance of reselecting the LTE base station configured as the NSA-anchor LTE cell. For example, updating the configuration parameters and increasing the reselection priority of the LTE base station configured as the NSA-anchor LTE cell can be performed by the Updating Module 524, depicted and described in Figure 5.

Conversely, in some other implementations, if it is determined that the SIB2 message does not include the upperLayerIndicator-r15 indicator, or includes the upperLayerIndicator-r15 indicator, but the indicator is not set to TRUE (i.e., determination block 926 = “No” ) , the UE, a processor of the UE, or another component of the UE, may re-perform the background search.

The initial performance of the background search, in addition to subsequent performances (or re-performances) of the background search may occur based on one or more background search timers. The background search timers may specify different timing intervals for the UE, a processor of the UE, or another component of the UE, to perform the background search. The background search timers may be implemented to balance power saving considerations (i.e., preserving the UE’s battery life) against the desire to camp on an NSA-anchor LTE cell which may provide higher throughput and data rates than the legacy LTE base station the UE is camped on. In some implementations, the background search timer may be configured as a short timer (NSA_Search_T (short) , or T (short) ) , a longer timer (NSA_Search_T (long) , or T (long) ) , a periodic timer (Tper) , or an aperiodic timer (Taper) .

The short timer may be initiated once the UE camps on the legacy LTE base station (block 918) , and the background search may be performed according to a set time frame (i.e., every 30 seconds, every 1 minute, every 2 minutes, etc. ) , or according to a formula, such as T (short) = T (n) , where n is a non-zero time value.

The long timer may be initiated after the initial performance of the background search, i.e., such as where the UE fails to find an NSA-anchor LTE cell in determination block 924 or when the UE fails to find an SIB2 message with an upperLayerIndicator-r15 set to TRUE in determination block 926. Under the design constraints of the longer timer, the background search may be performed according to a set time frame, which may be longer than the time frame for the short timer. For example, the longer timer time frame may be every 10 minutes, every 20 minutes, every 40 minutes, every 80 minutes, etc. In some implementations, the background search under the long timer may occur according to a formula, such as T (long) = 10*2^ (n-1) , when n>1 minute.

In some implementations, the periodic timer and the aperiodic timer may be initiated, if and when, the UE camps on an NSA-anchor LTE cell. In such implementations, the UE, a processor of the UE, or another component of the UE, can initiate a background search in a periodic manner (Tper) or aperiodic manner (Taper) to detect additional NSA-anchor LTE cells. If additional NSA-anchor LTE cells are detected, the UE, a processor of the UE, or another component of the UE, can be implemented to update the one or more NSA-anchor LTE cell-related databases. For example, the database updating can be performed by the Updating Module 524, depicted and described in Figure 5. Additionally, the Updating Module 524 can be implemented to update one or more configuration parameters to configure the camped on NSA-anchor LTE cell and the additionally detected NSA-anchor LTE cells as high selection priority cells (i.e., marked as NSA-anchor LTE cells in the NSA Fingerprint Database, so that next time the UE is in the coverage area, it may rapidly camp on the particular NSA-anchor LTE cell) .

At block 930, the UE, a processor of the UE, or another component of the UE, can be configured to perform cell reselection from the legacy LTE base station to an LTE base station configured as the NSA-anchor LTE cell. For example, the cell reselection can be performed by the Cell Reselection Performance Module 522, depicted and described in Figure 5. In some implementations, updating the configuration parameters (block 928) can occur before performing cell reselection (block 930) .

Figure 10 shows a diagram illustrating an example process 1000 performed, for example, by a mobile device, in accordance with various aspects of the present disclosure. The process 1000 is an example where the mobile device (for example, the UE 120) performs operations associated with establishing wireless connections with NSA-anchor LTE cells.

As shown in Figure 10, in some aspects, the process 1000 may include performing a first frequency scan for one or more NSA-anchor LTE cells (block 1010) . For example, the mobile device (using receive processor 258, transmit processor 264, controller/processor 280, memory 282, or other components) may perform a first frequency scan for one or more nonstandalone (NSA) -anchor Long Term Evolution (LTE) cells, as described above.

As further shown in Figure 10, in some aspects, the process 1000 may include determining whether a LTE base station is configured as an NSA-anchor LTE cell based on the first frequency scan (block 1020) . For example, the mobile device (using receive processor 258, transmit processor 264, controller/processor 280, memory 282, or other components) may determine whether a LTE base station is configured as an NSA-anchor LTE cell based on the first frequency scan, as described above.

As further shown in Figure 10, in some aspects, the process 1000 may include, in response to determining that the LTE base station is configured as the NSA-anchor LTE cell, camping on the LTE base station configured as the NSA-anchor LTE cell (block 1030) . For example, the mobile device (using receive processor 258, transmit processor 264, controller/processor 280, memory 282, or other components) may, in response to determining that the LTE base station is configured as the NSA-anchor LTE cell, camping on the LTE base station configured as the NSA-anchor LTE cell, as described above.

The process 1000 may include additional aspects, such as any single aspect or any combination of aspects described below or in connection with one or more other processes described elsewhere herein.

In a first aspect, the determining includes comparing results from the first frequency scan to one or more databases. In a second aspect, alone or in combination with the first aspect, the one or more databases includes at least one of a NSA Fingerprint Database and an NSA Frequency Database. In a third aspect, alone or in combination with one or more of the first and second aspects, the NSA Fingerprint Database includes NSA-anchor LTE cell information. In a fourth aspect, alone or in combination with one or more of the first through third aspects, the NSA-anchor LTE cell information includes historical information about one or more of the following: PLMN, LTE carrier frequency, E-UTRA EARFCN, PCIs, CGI, and cell reselection priority.

In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, the NSA Frequency Database includes frequencies of one or more NSA-anchor LTE cells. In a sixth aspect, alone or in combination with one or more of the first through fifth aspects, the NSA Frequency Database can be pre-configured based on operator network deployment. In a seventh aspect, alone or in combination with one or more of the first through sixth aspects, camping on the LTE base station configured as the NSA-anchor LTE cell includes establishing a wireless connection with the LTE base station configured as the NSA-anchor LTE cell.

In an eighth aspect, alone or in combination with one or more of the first through seventh aspects, establishing the wireless connection includes determining if an upperLayerIndication-r15 is set to TRUE, determining if a NR Measurement Object is configured, or determining if a NR SCG is added through a RRC Reconfiguration message. In a ninth aspect, alone or in combination with one or more of the first through eighth aspects, in response to determining that the LTE base station is not configured as the NSA-anchor LTE cell, further including performing a second frequency scan for one or more nearby NSA-anchor LTE cells.

In a tenth aspect, alone or in combination with one or more of the first through ninth aspects, the second frequency scan includes information related to one or more legacy LTE cells. In an eleventh aspect, alone or in combination with one or more of the first through tenth aspects, the process 1000 includes determining whether a second LTE base station is configured as an NSA-anchor LTE cell based on the second frequency scan; and in response to is determining that the second LTE base station is configured an the NSA-anchor LTE cell, camping on the second LTE base station configured as the NSA-anchor LTE cell. In a twelfth aspect, alone or in combination with one or more of the first through eleventh aspects, in response to determining that the second LTE base station is not configured as the NSA-anchor LTE cell, further including camping on the second LTE base station; and performing a background search for one or more nearby NSA-anchor LTE cells. In some implementations, the LTE base station and the second LTE base station can be different base stations. In some other implementations, the LTE base station and the second LTE base station can be the same base station.

In a thirteenth aspect, alone or in combination with one or more of the first through twelfth aspects, the process 1000 includes determining whether a third LTE base station is configured as an NSA-anchor LTE cell based on the background search; and in response to is determining that the third LTE base station is configured as the NSA-anchor LTE cell, determining if a SIB2 message includes an upperLayerIndicator-r15 indicator set to TRUE. In some implementations, the LTE base station, the second LTE base station and the third LTE base station can be different base stations. In some other implementations, the LTE base station, the second LTE base station and the third LTE base station can be the same base station. In a fourteenth aspect, alone or in combination with one or more of the first through thirteenth aspects, the determining includes comparing results from the background search to one or more resources. In a fifteenth aspect, alone or in combination with one or more of the first through fourteenth aspects, the one or more resources includes at least one of the NSA Fingerprint Database, the NSA Frequency Database, and a list of possible NSA frequencies configured in SIB5.

In a sixteenth aspect, alone or in combination with one or more of the first through fifteenth aspects, the performing the background search occurs periodically based on a Tper. In a seventeenth aspect, alone or in combination with one or more of the first through sixteenth aspects, the performing the background search occurs aperiodically. In an eighteenth aspect, alone or in combination with one or more of the first through seventeenth aspects, the background search occurs at time T (n) , and then again T (1) = T (short) , ... through T (n) = 10*2^ (n-1) when n>1 minute.

In a nineteenth aspect, alone or in combination with one or more of the first through eighteenth aspects, the process 1000 includes in response to is determining that the SIB2 message includes the upperLayerIndicator-r15 indicator set to TRUE, updating the NSA Fingerprint Database. In a twentieth aspect, alone or in combination with one or more of the first through nineteenth aspects, the process 1000 includes updating one or more configuration parameters to configure the third LTE base station as a high reselection priority NSA-anchor LTE cell. In a twenty first aspect, alone or in combination with one or more of the first through twentieth aspects, the process 1000 includes performing cell reselection to the third LTE base station configured as the NSA-anchor LTE cell.

The foregoing disclosure provides illustration and description, but is not intended to be exhaustive or to limit the aspects to the precise form disclosed. Modifications and variations may be made in light of the above disclosure or may be acquired from practice of the aspects.

As used herein, the term “component” is intended to be broadly construed 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. As used herein, the phrase “based on” is intended to be broadly construed to mean “based at least in part on. ”

Some aspects are described herein in connection with thresholds. As used herein, satisfying 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, or the like.

As used herein, 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 cover: a, b, c, a-b, a-c, b-c, and a-b-c.

The various illustrative logics, logical blocks, modules, circuits and algorithm processes described in connection with the aspects disclosed herein may be implemented as electronic hardware, computer software, or combinations of both. The interchangeability of hardware and software has been described generally, in terms of functionality, and illustrated in the various illustrative components, blocks, modules, circuits and processes described above. Whether such functionality is implemented in hardware or software depends upon the particular application and design constraints imposed on the overall system.

The hardware and data processing apparatus used to implement the various illustrative logics, logical blocks, modules and circuits described in connection with the aspects disclosed herein may be implemented or performed with a general purpose single-or multi-chip processor, a digital signal processor (DSP) , an application specific integrated circuit (ASIC) , a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor may be a microprocessor, or, any conventional processor, controller, microcontroller, or state machine. A processor also may be implemented as a combination of computing devices, for example, a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration. In some aspects, particular processes and methods may be performed by circuitry that is specific to a given function.

In one or more aspects, the functions described may be implemented in hardware, digital electronic circuitry, computer software, firmware, including the structures disclosed in this specification and their structural equivalents thereof, or in any combination thereof. Aspects of the subject matter described in this specification also can be implemented as one or more computer programs, i.e., one or more modules of computer program instructions, encoded on a computer storage media for execution by, or to control the operation of, data processing apparatus.

If implemented in software, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. The processes of a method or algorithm disclosed herein may be implemented in a processor-executable software module which may reside on a computer-readable medium. Computer-readable media includes both computer storage media and communication media including any medium that can be enabled to transfer a computer program from one place to another. A storage media may be any available media that may be accessed by a computer. By way of example, and not limitation, such computer-readable media may include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that may be used to store desired program code in the form of instructions or data structures and that may be accessed by a computer. Also, any connection can be properly termed a computer-readable medium. Disk and disc, as used herein, includes compact disc (CD) , laser disc, optical disc, digital versatile disc (DVD) , floppy disk, and Blu-ray disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above should also be included within the scope of computer-readable media. Additionally, the operations of a method or algorithm may reside as one or any combination or set of codes and instructions on a machine readable medium and computer-readable medium, which may be incorporated into a computer program product.

Various modifications to the aspects described in this disclosure may be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects without departing from the spirit or scope of this disclosure. Thus, the claims are not intended to be limited to the aspects shown herein, but are to be accorded the widest scope consistent with this disclosure, the principles and the novel features disclosed herein.

Additionally, a person having ordinary skill in the art will readily appreciate, the terms “upper” and “lower” are sometimes used for ease of describing the figures, and indicate relative positions corresponding to the orientation of the figure on a properly oriented page, and may not reflect the proper orientation of any device as implemented.

Certain features that are described in this specification in the context of separate aspects also can be implemented in combination in a single aspect. Conversely, various features that are described in the context of a single aspect also can be implemented in multiple aspects separately or in any suitable subcombination. Moreover, although features may be described above as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination may be directed to a subcombination or variation of a subcombination.

Similarly, while operations are depicted in the drawings in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. Further, the drawings may schematically depict one more example processes in the form of a flow diagram. However, other operations that are not depicted can be incorporated in the example processes that are schematically illustrated. For example, one or more additional operations can be performed before, after, simultaneously, or between any of the illustrated operations. In certain circumstances, multitasking and parallel processing may be advantageous. Moreover, the separation of various system components in the aspects described above should not be understood as requiring such separation in all aspects, and it should be understood that the described program components and systems can generally be integrated together in a single software product or packaged into multiple software products. Additionally, other aspects are within the scope of the following claims. In some cases, the actions recited in the claims can be performed in a different order and still achieve desirable results.

Claims

A method of performing cell selection by a processor of a mobile device, comprising:

performing a first frequency scan for one or more nonstandalone (NSA) -anchor Long Term Evolution (LTE) cells;

determining whether a LTE base station is configured as an NSA-anchor LTE cell based on the first frequency scan; and

in response to determining that the LTE base station is configured as the NSA-anchor LTE cell, camping on the LTE base station configured as the NSA-anchor LTE cell.
The method of claim 1, wherein the determining includes comparing results from the first frequency scan to one or more databases.
The method of claim 2, wherein the one or more databases includes at least one of a NSA Fingerprint Database and an NSA Frequency Database.
The method of claim 3, wherein the NSA Fingerprint Database includes NSA-anchor LTE cell information.
The method of claim 4, wherein the NSA-anchor LTE cell information includes historical information about one or more of the following: public land mobile network (PLMN) , LTE carrier frequency, Evolved Universal Terrestrial Radio Access (E-UTRA) Absolute Radio Frequency Channel Number (EARFCN) , Physical Cell Identifiers (PCIs) , Cell Global Identity (CGI) , and cell reselection priority.
The method of claim 3, wherein the NSA Frequency Database includes frequencies of one or more NSA-anchor LTE cells.
The method of claim 6, wherein the NSA Frequency Database can be pre-configured based on operator network deployment.
The method of claim 1, wherein camping on the LTE base station configured as the NSA-anchor LTE cell includes establishing a wireless connection with the LTE base station configured as the NSA-anchor LTE cell.
The method of claim 8, wherein establishing the wireless connection includes:

determining if an upperLayerIndication-r15 is set to TRUE;

determining if a new radio (NR) Measurement Object is configured; or

determining if a NR secondary cell group (SCG) is added through a radio resource control (RRC) Reconfiguration message.
The method of claim 1, wherein in response to determining that the LTE base station is not configured as the NSA-anchor LTE cell, further comprising:

performing a second frequency scan for one or more nearby NSA-anchor LTE cells.
The method of claim 10, wherein the second frequency scan includes information related to one or more legacy LTE cells.
The method of claim 10, further comprising:

determining whether a second LTE base station is configured as an NSA-anchor LTE cell based on the second frequency scan; and

in response to determining that the second LTE base station is configured an the NSA-anchor LTE cell, camping on the second LTE base station configured as the NSA-anchor LTE cell.
The method of claim 12, wherein in response to determining that the second LTE base station is not configured as the NSA-anchor LTE cell, further comprising:

camping on the second LTE base station; and

performing a background search for one or more nearby NSA-anchor LTE cells.
The method of claim 13, further comprising:

determining whether a third LTE base station is configured as an NSA-anchor LTE cell based on the background search; and

in response to determining that the third LTE base station is configured as the NSA-anchor LTE cell, determining if a system information block (SIB) two (SIB2) message includes an upperLayerIndicator-r15 indicator set to TRUE.
The method of claim 14, wherein the determining includes comparing results from the background search to one or more resources.
The method of claim 15, wherein the one or more resources includes at least one of the NSA Fingerprint Database, the NSA Frequency Database, and a list of possible NSA frequencies configured in SIB5.
The method of claim 13, wherein the performing the background search occurs periodically based on a timer (Tper) .
The method of claim 13, wherein the performing the background search occurs aperiodically.
The method of claim 18, wherein the background search occurs at time T (n) , and then again T (1) = T (short) , ...through T (n) = 10*2^ (n-1) when n>1 minute.
The method of claim 14, further comprising:

in response to determining that the SIB2 message includes the upperLayerIndicator-r15 indicator set to TRUE, updating the NSA Fingerprint Database.
The method of claim 20, further comprising:

updating one or more configuration parameters to configure the third LTE base station as a high reselection priority NSA-anchor LTE cell.
The method of claim 21, further comprising:

performing cell reselection to the third LTE base station configured as the NSA-anchor LTE cell.
A mobile device for wireless communication, comprising:

a memory; and

one or more processors operatively coupled to the memory, the memory and the one or more processors configured to:

perform a first frequency scan for one or more nonstandalone (NSA) -anchor Long Term Evolution (LTE) cells;

determine whether a LTE base station is configured as an NSA-anchor LTE cell based on the first frequency scan; and

in response to determining that the LTE base station is configured as the NSA-anchor LTE cell, camping on the LTE base station configured as the NSA-anchor LTE cell.
The mobile device of claim 23, wherein the one or more processors, when determining whether a LTE base station is configured as an NSA-anchor LTE cell based on the first frequency scan, are to compare results from the first frequency scan to one or more databases.
The mobile device of claim 24, wherein the one or more databases includes at least one of a NSA Fingerprint Database and an NSA Frequency Database.
The mobile device of claim 25, wherein the NSA Fingerprint Database includes NSA-anchor LTE cell information.
The mobile device of claim 26, wherein the NSA-anchor LTE cell information includes historical information about one or more of the following: public land mobile network (PLMN) , LTE carrier frequency, Evolved Universal Terrestrial Radio Access (E-UTRA) Absolute Radio Frequency Channel Number (EARFCN) , Physical Cell Identifiers (PCIs) , Cell Global Identity (CGI) , and cell reselection priority.
The mobile device of claim 25, wherein the NSA Frequency Database includes frequencies of one or more NSA-anchor LTE cells.
The mobile device of claim 28, wherein the NSA Frequency Database can be pre-configured based on operator network deployment.
The mobile device of claim 23, wherein the one or more processors, when camping on the LTE base station configured as the NSA-anchor LTE cell, are to establish a wireless connection with the LTE base station configured as the NSA-anchor LTE cell.
The mobile device of claim 30, wherein the one or more processors, when establishing the wireless connection, are to:

determine if an upperLayerIndication-r15 is set to TRUE;

determine if a new radio (NR) Measurement Object is configured; or

determine if a NR secondary cell group (SCG) is added through a radio resource control (RRC) Reconfiguration message.
The mobile device of claim 23, wherein, in response to determining that the LTE base station is not configured as the NSA-anchor LTE cell, the one or more processors are further configured to:

perform a second frequency scan for one or more nearby NSA-anchor LTE cells.
The mobile device of claim 32, wherein the second frequency scan includes information related to one or more legacy LTE cells.
The mobile device of claim 32, wherein the one or more processors are further configured to:

determine whether a second LTE base station is configured as an NSA-anchor LTE cell based on the second frequency scan; and

in response to determining that the second LTE base station is configured an the NSA-anchor LTE cell, camp on the second LTE base station configured as the NSA-anchor LTE cell.
The mobile device of claim 34, wherein, in response to determining that the second LTE base station is not configured as the NSA-anchor LTE cell, wherein the one or more processors are further configured to:

camp on the second LTE base station; and

perform a background search for one or more nearby NSA-anchor LTE cells.
The mobile device of claim 35, wherein the one or more processors are further configured to:

determine whether a third LTE base station is configured as an NSA-anchor LTE cell based on the background search; and

in response to determining that the third LTE base station is configured as the NSA-anchor LTE cell, determine if a system information block (SIB) two (SIB2) message includes an upperLayerIndicator-r15 indicator set to TRUE.
The mobile device of claim 36, wherein, the one or more processors, when determining if the SIB2 message includes the upperLayerIndicator-r15 indicator set to TRUE, are to compare results from the background search to one or more resources.
The mobile device of claim 37, wherein the one or more resources includes at least one of the NSA Fingerprint Database, the NSA Frequency Database, and a list of possible NSA frequencies configured in SIB5.
The mobile device of claim 35, wherein the one or more processors, when performing a background search for one or more nearby NSA-anchor LTE cells, are to perform the background search periodically based on a timer (Tper) .
The mobile device of claim 35, wherein the one or more processors, when performing a background search for one or more nearby NSA-anchor LTE cells, are to perform the background search aperiodically.
The mobile device of claim 40, wherein the background search occurs at time T(n) , and then again T (1) = T (short) , ...through T (n) = 10*2^ (n-1) when n>1 minute.
The mobile device of claim 36, wherein the one or more processors are further configured to:

in response to determining that the SIB2 message includes the upperLayerIndicator-r15 indicator set to TRUE, update the NSA Fingerprint Database.
The mobile device of claim 42, wherein the one or more processors are further configured to:

update one or more configuration parameters to configure the third LTE base station as a high reselection priority NSA-anchor LTE cell.
The mobile device of claim 43, wherein the one or more processors are further configured to:

perform cell reselection to the third LTE base station configured as the NSA-anchor LTE cell.
A non-transitory computer-readable medium storing one or more instructions for wireless communication, comprising:

one or more instructions that, when executed by one or more processors of a mobile device, cause the one or more processors to:

perform a first frequency scan for one or more nonstandalone (NSA) -anchor Long Term Evolution (LTE) cells;

determine whether a LTE base station is configured as an NSA-anchor LTE cell based on the first frequency scan; and

in response to determining that the LTE base station is configured as the NSA-anchor LTE cell, camping on the LTE base station configured as the NSA-anchor LTE cell.
The non-transitory computer-readable medium of claim 45, wherein the one or more instructions, that cause the one or more processors to determine whether the LTE base station is configured as the NSA-anchor LTE cell based on the first frequency scan, cause the one or more processors to compare results from the first frequency scan to one or more databases.
The non-transitory computer-readable medium of claim 46, wherein the one or more databases includes at least one of a NSA Fingerprint Database and an NSA Frequency Database.
The non-transitory computer-readable medium of claim 47, wherein the NSA Fingerprint Database includes NSA-anchor LTE cell information.
The non-transitory computer-readable medium of claim 48, wherein the NSA-anchor LTE cell information includes historical information about one or more of the following: public land mobile network (PLMN) , LTE carrier frequency, Evolved Universal Terrestrial Radio Access (E-UTRA) Absolute Radio Frequency Channel Number (EARFCN) , Physical Cell Identifiers (PCIs) , Cell Global Identity (CGI) , and cell reselection priority.
The non-transitory computer-readable medium of claim 47, wherein the NSA Frequency Database includes frequencies of one or more NSA-anchor LTE cells.
The non-transitory computer-readable medium of claim 50, wherein the NSA Frequency Database can be pre-configured based on operator network deployment.
The non-transitory computer-readable medium of claim 45, wherein the one or more instructions, that cause the one or more processors to camp on the LTE base station configured as the NSA-anchor LTE cell, cause the one or more processors to establish a wireless connection with the LTE base station configured as the NSA-anchor LTE cell.
The non-transitory computer-readable medium of claim 52, wherein establishing the wireless connection includes:

determine if an upperLayerIndication-r15 is set to TRUE;

determine if a new radio (NR) Measurement Object is configured; or

determine if a NR secondary cell group (SCG) is added through a radio resource control (RRC) Reconfiguration message.
The non-transitory computer-readable medium of claim 45, wherein in response to determining that the LTE base station is not configured as the NSA-anchor LTE cell, wherein the one or more instructions, when executed by the one or more processors, further cause the one or more processors to:

perform a second frequency scan for one or more nearby NSA-anchor LTE cells.
The non-transitory computer-readable medium of claim 54, wherein the second frequency scan includes information related to one or more legacy LTE cells.
The non-transitory computer-readable medium of claim 54, wherein the one or more instructions, when executed by the one or more processors, further cause the one or more processors to:

determine whether a second LTE base station is configured as an NSA-anchor LTE cell based on the second frequency scan; and

in response to determining that the second LTE base station is configured an the NSA-anchor LTE cell, camping on the second LTE base station configured as the NSA-anchor LTE cell.
The non-transitory computer-readable medium of claim 56, wherein, in response to determining that the second LTE base station is not configured as the NSA-anchor LTE cell, the one or more instructions, when executed by the one or more processors, further cause the one or more processors to:

camp on the second LTE base station; and

perform a background search for one or more nearby NSA-anchor LTE cells.
The non-transitory computer-readable medium of claim 57, wherein the one or more instructions, when executed by the one or more processors, further cause the one or more processors to:

determine whether a third LTE base station is configured as an NSA-anchor LTE cell based on the background search; and

in response to determining that the third LTE base station is configured as the NSA-anchor LTE cell, determine if a system information block (SIB) two (SIB2) message includes an upperLayerIndicator-r15 indicator set to TRUE.
The non-transitory computer-readable medium of claim 58, wherein the one or more instructions, that cause the one or more processors to determine if the SIB2 message includes the upperLayerIndicator-r15 indicator set to TRUE, cause the one or more processors to compare results from the background search to one or more resources.
The non-transitory computer-readable medium of claim 59, wherein the one or more resources includes at least one of the NSA Fingerprint Database, the NSA Frequency Database, and a list of possible NSA frequencies configured in SIB5.
The non-transitory computer-readable medium of claim 57, wherein the one or more instructions, that cause the one or more processors to perform the background search, cause the one or more processors to perform the background search periodically based on a timer (Tper) .
The non-transitory computer-readable medium of claim 57, wherein the one or more instructions, that cause the one or more processors to perform the background search, cause the one or more processors to perform the background search aperiodically.
The non-transitory computer-readable medium of claim 62, wherein the background search occurs at time T (n) , and then again T (1) = T (short) , ...through T (n) = 10*2^ (n-1) when n>1 minute.
The non-transitory computer-readable medium of claim 58, wherein the one or more instructions, when executed by the one or more processors, further cause the one or more processors to:

in response to determining that the SIB2 message includes the upperLayerIndicator-r15 indicator set to TRUE, update the NSA Fingerprint Database.
The non-transitory computer-readable medium of claim 64, wherein the one or more instructions, when executed by the one or more processors, further cause the one or more processors to:

update one or more configuration parameters to configure the third LTE base station as a high reselection priority NSA-anchor LTE cell.
The non-transitory computer-readable medium of claim 65, wherein the one or more instructions, when executed by the one or more processors, further cause the one or more processors to:

perform cell reselection to the third LTE base station configured as the NSA-anchor LTE cell.
An apparatus for wireless communication, comprising:

means for performing a first frequency scan for one or more nonstandalone (NSA) -anchor Long Term Evolution (LTE) cells;

means for determining whether a LTE base station is configured as an NSA-anchor LTE cell based on the first frequency scan; and

in response to determining that the LTE base station is configured as the NSA-anchor LTE cell, means for camping on the LTE base station configured as the NSA-anchor LTE cell.
The apparatus of claim 67, wherein the means for determining includes means for comparing results from the first frequency scan to one or more databases.
The apparatus of claim 68, wherein the one or more databases includes at least one of a NSA Fingerprint Database and an NSA Frequency Database.
The apparatus of claim 69, wherein the NSA Fingerprint Database includes NSA-anchor LTE cell information.
The apparatus of claim 70, wherein the NSA-anchor LTE cell information includes historical information about one or more of the following: public land mobile network (PLMN) , LTE carrier frequency, Evolved Universal Terrestrial Radio Access (E-UTRA) Absolute Radio Frequency Channel Number (EARFCN) , Physical Cell Identifiers (PCIs) , Cell Global Identity (CGI) , and cell reselection priority.
The apparatus of claim 69, wherein the NSA Frequency Database includes frequencies of one or more NSA-anchor LTE cells.
The apparatus of claim 72, wherein the NSA Frequency Database can be pre-configured based on operator network deployment.
The apparatus of claim 67, wherein the means for camping on the LTE base station configured as the NSA-anchor LTE cell includes means for establishing a wireless connection with the LTE base station configured as the NSA-anchor LTE cell.
The apparatus of claim 74, wherein the means for establishing the wireless connection includes:

means for determining if an upperLayerIndication-r15 is set to TRUE;

means for determining if a new radio (NR) Measurement Object is configured; or

means for determining if a NR secondary cell group (SCG) is added through a radio resource control (RRC) Reconfiguration message.
The apparatus of claim 67, wherein in response to determining that the LTE base station is not configured as the NSA-anchor LTE cell, the apparatus further comprises:

means for performing a second frequency scan for one or more nearby NSA-anchor LTE cells.
The apparatus of claim 76, wherein the second frequency scan includes information related to one or more legacy LTE cells.
The apparatus of claim 76, further comprising:

means for determining whether a second LTE base station is configured as an NSA-anchor LTE cell based on the second frequency scan; and

in response to determining that the second LTE base station is configured an the NSA-anchor LTE cell, means for camping on the second LTE base station configured as the NSA-anchor LTE cell.
The apparatus of claim 78, wherein in response to determining that the second LTE base station is not configured as the NSA-anchor LTE cell, the apparatus further comprises:

means for camping on the second LTE base station; and

means for performing a background search for one or more nearby NSA-anchor LTE cells.
The apparatus of claim 79, further comprising:

means for determining whether a third LTE base station is configured as an NSA-anchor LTE cell based on the background search; and

in response to determining that the third LTE base station is configured as the NSA-anchor LTE cell, means for determining if a system information block (SIB) two (SIB2) message includes an upperLayerIndicator-r15 indicator set to TRUE.
The apparatus of claim 80, wherein the means for determining includes means for comparing results from the background search to one or more resources.
The apparatus of claim 81, wherein the one or more resources includes at least one of the NSA Fingerprint Database, the NSA Frequency Database, and a list of possible NSA frequencies configured in SIB5.
The apparatus of claim 79, wherein the means for performing the background search occurs periodically based on a timer (Tper) .
The apparatus of claim 79, wherein the means for performing the background search occurs aperiodically.
The apparatus of claim 84, wherein the background search occurs at time T (n) , and then again T (1) = T (short) , ...through T (n) = 10*2^ (n-1) when n>1 minute.
The apparatus of claim 80, further comprising:

in response to determining that the SIB2 message includes the upperLayerIndicator-r15 indicator set to TRUE, means for updating the NSA Fingerprint Database.
The apparatus of claim 86, further comprising:

means for updating one or more configuration parameters to configure the third LTE base station as a high reselection priority NSA-anchor LTE cell.
The apparatus of claim 87, further comprising:

means for performing cell reselection to the third LTE base station configured as the NSA-anchor LTE cell.