Adaptive cell search

Abstract

The invention relates to adaptive cell search. This disclosure provides systems, methods, and circuits for performing adaptive cell search. In one example, a method for a user equipment (UE) includes determining that the UE has entered an out-of-coverage (OOC) state; and in response, configuring a cell search pattern that defines a series of scheduled search instances for each of the one or more frequency sets. The timing of the series of scheduled search instances is based on the time the UE enters an OOC state, and the cell search pattern is configured to cause a respective minimum search rate of a respective set of frequencies to be performed. A set of frequencies is searched based on the configured cell search pattern.

Description

Background Art

[0001] The present disclosure relates generally to wireless communications, and more particularly to techniques that may be used by a user equipment (UE) to search for cellular network cells when the UE is out of coverage (OOC). BRIEF DESCRIPTION OF THE DRAWINGS

[0002] Some examples of circuits, devices and / or methods will be described below by way of example only.In this context, reference will be made to the accompanying drawings.

[0003] Figure 1 is a diagram of an example search control circuit of a UE in accordance with various aspects described.

[0004] Figure 2 According to the various aspects described Figure 1 Functional block diagram of the search mode timer.

[0005] Figure 3A , Figure 3B and Figure 3C is a diagram summarizing a cell search mode and an adjustment of the cell search mode due to a triggering event according to various aspects described.

[0006] Figure 4 According to the various aspects described Figure 1 Functional block diagram of the self-organizing (ad hoc) search trigger circuit.

[0007] Figure 5 According to the various aspects described Figure 1 Functional block diagram of a search frequency / band update circuit.

[0008] Fig. 6A and Figure 6B is a flowchart outlining an example method of performing an adaptive cell search in accordance with various described aspects.

[0009] Figure 7 is a functional block diagram of a wireless communication network in accordance with various aspects described.

[0010] Figure 8 A simplified block diagram of a network device in accordance with various aspects described is illustrated. DETAILED DESCRIPTION

[0011] The present disclosure is described with reference to the accompanying drawings. Similar parts in each figure are represented by similar reference characters. The accompanying drawings are not drawn to scale, and these drawings are provided only for illustrating the present disclosure. Several aspects of the present disclosure are described below with reference to example applications for illustration. Many specific details, relationships and methods are set forth to provide an understanding of the present disclosure. The present disclosure is not limited by the order of the actions or events illustrated, because some actions can occur in different orders and / or occur simultaneously with other actions or events. In addition, not all illustrated actions or events are necessary to implement the method according to the selected present disclosure.

[0012] Around the world, different radio access technologies (RATs) (e.g., LTE, 5GNR, etc.) are deployed on multiple frequency bands on a per-RAT basis, where the frequency bands associated with different RATs vary based on countries and regions. With the introduction of 5G NR, there may be four RATs (2G / 3G / 4G / 5G) available for search, and each RAT has multiple supported frequencies and bands. In addition, for 5G NR, there are frequencies ranging from FR1 (below 6GHz) to FR2 (millimeter wave). This means that there is a large and increasing spectrum of frequencies and bands that out-of-coverage (OOC) UEs can search to find cells. In order to save power, cell searches should be targeted to frequencies / bands and performed during the time period that is most likely to result in cell recovery.

[0013] When the UE is switched on, a public land mobile network (PLMN) may be selected by the non-access stratum (NAS). NAS may provide a list of other PLMNs and corresponding priorities that the access stratum (AS) may use for cell selection and reselection (if available). One or more associated RATs may be set for each PLMN. The UE searches for a suitable cell for the selected PLMN and RAT. The UE selects the cell to provide available services and will monitor the control channel of the cell. This process may be referred to as "camping on a cell". In some cases, the UE may then record its presence in the tracking area of ​​the selected cell. If the UE finds a more suitable cell, the UE may reselect the cell and camp on the cell based on the cell reselection criteria. The UE may search for a higher priority PLMN at regular time intervals.

[0014] If the UE is out of coverage, also known as out of service (OOS), it may attempt to reacquire service by executing a cell search algorithm. In the design of the cell search algorithm, a balance is struck between power usage and cell acquisition performance. To save power while executing the cell search algorithm, the UE may alternate between operating in a scanning state, which consumes power but may result in service acquisition, and operating in a sleep state, which saves power but delays service acquisition.

[0015] Some cell search algorithms are divided into stored list search (SLS), derived band search (DBS) and remaining band search (RBS). SLS includes the most recently used frequencies stored in a list by the UE. Due to the limited number of frequencies on the list, SLS can have a significantly shorter duration than DBS and can therefore be executed at a faster rate. SLS can be used for short OOC scenarios, however, as the duration of OOC increases, SLS has a reduced probability of success.

[0016] DBS is performed on a frequency band that can be found in the last pre-empted area, which can be derived from the frequencies stored by the UE and searched in the SLS. For example, for each frequency in the SLS, the entire frequency band including the frequency is searched in the DBS. DBS-MCC (Mobile Country Code) can be performed on a frequency band that is mapped to an MCC for a country adjacent to the UE location but is not searched in the DBS. DBS or DBS-MCC can have a longer duration than SLS.

[0017] The RBS searches all remaining bands that have not been searched in the DBS or DBS-MCC, which may include all bands for a particular RAT. The RBS therefore uses a lot of time and power, especially for 5G NR. The RBS has a longer duration than the DBS, and in some examples may be performed on a fairly limited basis, such as every x DBSs or when no suitable cell is found using the SLS or DBS.

[0018] Some cell search algorithms make it difficult to determine the specific time when DBS / RBS will be performed (e.g., relative to the time when the UE loses coverage), leading to ambiguity in design considerations. In addition, many search algorithms do not support self-organizing triggering of searches in response to UE-related triggering events, or dynamically adjusting the frequencies and bands searched in SLS, DBS, or DBS-MCC.

[0019] Systems, architectures, and devices that support adaptive cell search are described herein. A cell search mode is provided that can be flexibly and dynamically configured to search different frequencies or frequency band sets at a varying rate relative to the time when the UE loses coverage. The cell search mode can be configured based on the power state of the UE. The cell search mode can be divided into multiple time phases, wherein the earlier time phases include more intensive searches for frequencies and frequency bands related to the past or current location of the UE, and the later time phases include less intensive searches on a more comprehensive set of frequency bands. A self-organizing trigger mechanism is provided that can trigger an immediate search (e.g., not scheduled by a cell search mode) in response to a change in the operating state of the UE. In addition, information from a database that maps operating frequencies to the location of UEs in coverage can be used to: trigger a search when a change in the location of the UE is detected; or update a set of frequencies that will be searched based on the frequencies and frequency bands supported in the new location.

[0020] Figure 1 An exemplary adaptive cell search system including a search control circuit 110 and a search circuit 150 is illustrated. In some aspects, the search control circuit 110 and the search circuit 150 are implemented by a baseband processor of a UE that executes stored instructions. Figure 8 Functional block diagram of an exemplary UE of FIG. Search control circuit 110 receives information about the status of various UE operating parameters. In some examples, the information is received from an application processor of the UE. Based on the information, search control circuit 110 provides a search trigger and a frequency and / or frequency band update to search circuit 150. When triggered by search control circuit 110, search circuit 150 performs a search or scan of one or more frequency sets (FS) associated with the trigger.

[0021] A frequency set is a set of frequencies or frequency bands associated with a given type of cell search. A frequency set may include a range or sub-range of frequencies searched in a list mode search or a frequency band searched in a range mode search. Figure 5 As illustrated in , the first frequency set includes frequencies stored by the UE to be searched by the SLS. The second frequency set includes frequency bands derived from the frequencies of the first frequency set to be searched by the DBS. The third frequency set includes frequency bands derived from the mobile country code of a country close to the UE's location to be searched by the DBS-MCC. The fourth frequency set includes the remaining frequency bands supported by the current PLMN / RAT that are not included in the first three frequency sets (for example, frequencies to be searched by the RBS). The fifth frequency set includes frequency bands associated with a specific band search (SBS) or frequency bands stored in association, with which the UE is configured or preconfigured. The sixth frequency set includes frequency bands searched in a full band search (FBS), which can be used when performing a manual PLMN search.

[0022] Although the terms SLS, DBS, DBS-MCC, RBS, SBS, FBS, etc. may have specific definitions as terms of art, as used herein, these terms may be interpreted more broadly. For example, a first set of frequencies that may be referred to interchangeably with SLS herein may include frequencies with the highest likelihood of success based on the possible location of the UE. These frequencies may include frequencies stored in a list when the UE loses coverage and / or frequencies associated with the current cell-level location of the UE or even a wider area surrounding the location of the UE. The specific frequencies searched in the SLS may be updated by the search control circuit 110, as will be referred to in the reference Figure 5 The second frequency set or DBS may include frequency bands derived from this more broadly defined SLS frequency set, etc.

[0023] Exemplary UE status information that the search control circuit 110 may use when controlling the search circuit 150 includes a motion state (e.g., a UE static state or a UE motion state) that may be determined based on sensor data (e.g., accelerometer data), a screen state (e.g., locked / unlocked), a UE sleep state (e.g., awake or dormant), a power state of the UE (e.g., a percentage of remaining battery power or a low power mode), whether the UE is near an international border, whether the UE has an active WiFi connection, etc.

[0024] The search control circuit 110 includes a search mode timer 120 and a self-organizing search trigger circuit 130, which generate a scheduled search trigger and a self-organizing search trigger, respectively. Frequencies associated with cells adjacent to the location of the UE and frequencies associated with a wider surrounding area can be received from the application processor and used by the search frequency / band update circuit 140 to update the frequencies / bands included in the frequency set searched by the search circuit 150.

[0025] Figure 2 An exemplary search pattern timer algorithm for generating a corresponding scheduling search trigger associated with a corresponding frequency set according to a cell search pattern is illustrated. The cell search pattern is established relative to the time when the UE loses coverage (e.g., enters the OOC state). Each timer 222 to 225 is associated with a specific frequency set (FS), where the FS can be SLS, DBS, DBS-MCC, RBS, etc. When the timer reaches 0, a search for the frequency set associated with it is triggered. After the search is triggered, the timer is reset to a value determined based on its timer algorithm.

[0026] Each timer algorithm generates a search trigger for a given set of frequencies based on configurable mode parameters. The mode parameters include an initial gap time or search interval (T ) that defines the initial value of the timer. FS(0)), Gap Time Increment (GTI FS ) and the maximum gap time (GTMAX FS ). Initial gap time T FS (0) specifies the interval or gap between the time the UE loses coverage and the first search for a given FS. The gap time increment specifies the interval or gap between consecutive searches for a given FS, and the maximum gap time increment specifies the maximum allowed interval or gap between consecutive searches for a given FS. Optionally, the timer algorithm may additionally be based on a configurable increment multiplier MUL FS To generate a scheduled search trigger, the configurable increment multiplier defines the scaling factor applied to the gap time increment after each consecutive search to generate an increased gap time. Once the maximum gap time is reached, the search rate of the FS is constant based on the maximum gap time.

[0027] The cell search pattern parameters can be configured by a search control circuit (e.g., a baseband processor executing a control algorithm), and different values ​​can be configured for use when the UE is in a static state and when the UE is in motion. In some aspects, when the UE is in motion, the initial search interval and other pattern parameters are configured with smaller values ​​than in a static state.

[0028] The SLS timer 222 has a configurable waiting time that divides the SLS search mode into a first phase and a second phase. In some examples, the waiting time is 300 seconds. In some aspects, the search rate of the SLS during Phase 1 is more aggressive than during Phase 2 (e.g., the intervals therebetween are smaller). When the UE loses coverage, the waiting time or the length of Phase 1 can be configured based on the power state of the UE. Therefore, when the UE has a full battery remaining when the UE loses coverage, a maximum waiting time can be configured, and when the UE has less than a full battery remaining when the UE loses coverage, a shorter waiting time can be configured. In the illustrated example, during Phase 1, the interval between consecutive SLSs remains constant at the initial search interval value.

[0029] At the beginning of phase 2, the timer algorithm of timer 222 increases the interval between consecutive SLSs based on the gap time increment. Figure 3A As shown, the timer algorithm of timer 222 again increases the interval between consecutive SLS increases by the gap time increment simultaneously with each triggered DBS. Figure 2 Only two phases defined by wait times are disclosed in the example of , but additional phases with unique search timing characteristics may be defined by additional wait times or other means.

[0030] The timer algorithms for the DBS timer 223, the DBS-MCC timer 224, and the RBS timer 225 are based on the current gap time increment value and the increment multiplier MUL, respectively. FS Determine the next timer value T FS (n+1). The current gap time increment value GTI FS (n) multiplied by the increment multiplier MUL FS , to generate the next gap time increment value GTI FS (n+1) and the next timer value T FS (n+1). Once the maximum gap time is reached, the search rate will remain constant based on the maximum gap time.

[0031] Figure 3A Example search patterns for SLS, DBS, and RBS are illustrated. Vertical lines with normal weight represent SLS. Thick vertical lines represent DBS. Thick gray vertical lines represent RBS. It can be seen that during phase 1, SLS search instances are scheduled at fixed SLS intervals, while DBS search instances are scheduled at increasing intervals based on increasing gap time increments (e.g., due to the effect of the gap time increment multiplier (MUL) in the timer algorithm). Due to the length of the initial search interval for RBS, RBS search instances are not scheduled during phase 1.

[0032] In Phase 2, DBS continues with a pattern of increasing intervals based on increasing interval time increments. RBS (0) The first RBS is scheduled to occur simultaneously with the fourth DBS.

[0033] At the beginning of phase 2, the gap time interval between SLSs increases based on the configured gap time increment, and the search rate of SLSs remains constant (e.g., with a constant interval between consecutive searches) until the next DBS. Simultaneously with each DBS, the interval between SLSs increases based on the configured gap time increment until a maximum gap time. Although specific patterns are disclosed for SLS search instances in phases 1 and 2, the timer algorithm of timer 222 can schedule SLS search instances according to other patterns based on different pattern parameter values.

[0034] Figure 3B The cell search patterns for DBS and RBS are illustrated, while SLS is not shown. Figure 3B With Figure 3A Different time scales make Figure 3B The increased interval between the scheduled DBS and the scheduled RBS can be Figure 3B Seen in.

[0035] Any or all cell search pattern parameters including the waiting time of SLS, the initial search interval, the gap time increment, the maximum gap time, and the gap time increment multiplier may be configurable and have different configurations for the static state and the motion state of the UE. The motion state of the UE may be received from the application processor or determined by the baseband processor based on sensor data. Generally speaking, when the UE is in motion, the cell search pattern parameters may have lower values, resulting in more frequent searches. In some examples, the cell search pattern parameter values ​​for the motion state may be half of the corresponding values ​​for the static state.

[0036] The search mode timer algorithm may automatically adjust the cell search mode parameters based on the real-time operating conditions of the UE, such as the power level of the UE when the UE loses coverage or when the UE enters a low power mode (LPM) when the UE is in OOC. When the UE loses coverage, the waiting time may be adjusted based on the power state of the UE. For example, when the UE has full power when the UE loses coverage, the waiting time may be set to a maximum value, and when the UE has less than full power when the UE loses coverage, the waiting time may be set to a proportionally lower value. When the UE enters LPM, the gap time increment value and / or the gap time increment multiplier value of the selected timer or all timers may be increased to reduce the frequency.

[0037] A WiFi connection may indicate that the UE is operating within a limited location range (inside a building). Recognizing this concept, when a WiFi connection is detected, the cell search parameters may be adjusted to achieve a reduced search rate. For example, when a WiFi connection is detected, the timer may use a cell search mode parameter value associated with a static state, rather than a parameter value associated with a motion state. Alternatively or additionally, when a WiFi connection is detected, the gap time increment may be increased, such as by changing the value of the gap time increment multiplier.

[0038] In some examples, the gap time increment value of the motion state can be adjusted inversely proportional to the change in the UE's motion rate, so that when the motion rate increases, the gap time increment decreases and the search rate increases, and when the motion rate decreases, the gap time increment increases and the search rate decreases.

[0039] In this way, when the UE loses coverage, the cell search mode timer 220 will trigger a series of scheduled search time instances for the various frequency sets as described above. Each scheduled search time instance occurs at a predetermined time relative to the time when the UE loses coverage. The minimum search rate for each FS can be controlled based on the value set for the maximum gap time.

[0040] Real-time UE operating conditions may provide an indication that coverage is available and / or desired by the user.Therefore, it may be beneficial to support self-organized triggering of cell search based on the operating state or location of the UE. Figure 4 An example self-organizing search trigger circuit 430 is illustrated, which generates a self-organizing search trigger that causes an immediate search for various FSs (e.g., SLS 452, DBS 454, DBS-MCC 455, RBS 456, SBS 458, FBS 459) in response to specific UE status or location information. The self-organizing search trigger circuit 430 monitors various aspects of UE operation to detect trigger criteria. This information related to UE operation can be received from the application processor 490.

[0041] The trigger criteria include the UE screen being unlocked, the UE transitioning from a sleep state to a wake-up state, or the UE being near a boundary location. For example, DBS can be triggered when the UE screen is unlocked or transitions from screen sleep to screen wake-up. DBS can be triggered when the UE wakes up from a sleep state. FBS can be triggered when a cell signal in an unknown frequency band is detected. When the self-organizing search trigger circuit 430 determines that the UE's position is close to the boundary, the self-organizing search trigger circuit 430 can trigger DBS-MCC. The application processor can warn the self-organizing search trigger circuit 430 that the UE is close to the boundary based on the geographic location of the UE determined by the application processor. Alternatively, the baseband processor of the UE can detect signals from cells with different MCCs and infer that the UE is near the boundary. When the stored frequency information mapped to the UE's position changes (see, for example Figure 5 APACSDB) can trigger SLS or DBS. Other criteria can be used. Although each of these example self-organizing triggers causes a search for a single FS, in other examples, the self-organizing trigger can cause a search for multiple FSs.

[0042] The self-organizing search trigger circuit 430 is configured with a trigger interval 435 for each FS. The trigger interval defines the time after the self-organizing trigger during which no subsequent self-organizing triggers for the same (or any) FS may be generated. This reduces the likelihood of performing multiple unsuccessful searches for the same FS in response to multiple satisfaction of the self-organizing trigger criteria within a short duration or satisfying different criteria in close succession.

[0043] After providing a self-organizing trigger that causes a cell search for one or more frequency sets, the self-organizing search trigger circuit 430 provides a reset signal to one or more search mode timers in the search mode timer 420. This causes the timing of the scheduled search instance to be triggered by the timer to be adjusted while maintaining the minimum search rate configured by the maximum gap time parameter. In some examples, only the timer associated with the FS being searched in response to the self-organizing trigger is reset, and in other examples, after triggering a self-organizing search for any FS, the self-organizing search trigger circuit 430 resets other or all FS timers.

[0044] Figure 3C An example of the interaction between the search pattern timer 420 and the self-organizing search trigger circuit 430 for DBS and RBS is illustrated. During the illustrated time period, six DBS scheduled search instances DBS1 to DBS6 and a single RBS scheduled search instance RBS1 are scheduled based on the time when the UE loses coverage. Subsequent RBSs are scheduled to appear outside the illustrated time period. It can be seen that for the DBS scheduled search instances, the gap or interval between consecutive searches increases as the increment increases until the maximum gap time is reached after the third scheduled search instance DBS3. Note that SLS can also be performed during the illustrated time period. Figure 3C The time periods shown in are scheduled, but have been omitted for simplicity. Figure 3A The SLS pattern and its relationship to the DBS pattern are illustrated in FIG.

[0045] After the unsuccessful scheduled cell search DBS1, a trigger event occurs at an offset time before the second scheduled search instance DBS2. In response, the self-organizing search trigger circuit triggers DBS at the time indicated by the vertical dashed line DBS2'. The self-organizing search trigger circuit also resets the DBS timer so that the timer is as if the scheduled search instance DBS2 has been executed in advance. This means that subsequent scheduled search instances DBS3 to DBS6 will occur at modified (earlier) times as indicated by the adjusted scheduled search instances DBS3' to DBS6'. However, the same interval or gap between the adjusted DBS instances is maintained as originally determined by the timer. Therefore, based on the offset between the self-organizing triggered DBS and the subsequent scheduled DBS search instance (e.g., the time difference between DBS2' and DBS2), each scheduled DBS search instance occurs earlier than originally scheduled. This maintains the DBS search rate to at least the minimum search rate configured by the maximum gap time. In some examples, all cell search mode timers are reset in this manner, not just the timers associated with the FS searched in response to the self-organizing trigger.

[0046] In some examples, RBS may be executed independently of DBS. In this case, the timing of RBS1 is not affected by the self-organizing triggered DBS2'. In other examples, RBS is always executed immediately after DBS. In this case, RBS is not automatically executed when the RBS timer expires, but the RBS timer is checked when the DBS timer expires, and if the RBS timer has expired, RBS is executed immediately after DBS. In the illustrated example, when DBS4' is executed, the RBS time has not expired, and RBS1 is not executed in conjunction with DBS4'. Instead, RBS1 will be executed in conjunction with DBS5', as shown by the thick gray vertical dashed line RBS1'.

[0047] Figure 3C The trigger interval is illustrated in . During this interval after a trigger event, another search for the same FS may not be allowed to be triggered by the self-organizing search trigger circuit, and any trigger event for a DBS in this interval is ignored.

[0048] Figure 5 An example search frequency / band update circuit 540 is illustrated that dynamically updates the frequencies and / or bands searched in a set of frequencies during a corresponding cell search type. Figure 5 In the example of , the frequency set includes SLS 552, DBS 554, DBS-MCC 555, RBS 556, SBS 558, and FBS 559. In other examples, different frequency sets may include different groupings of frequencies or frequency bands suitable for different OOC scenarios.

[0049] The search frequency / band update circuit 540 receives frequency / band information from the application processor 590. The application processor 590 obtains frequency / band information from an application processor assisted cell search (APACS) database (DB) 570 stored in the UE. The APACSDB 570 is a global database that can be maintained and updated by a network server, where a new version is periodically provided to the UEs in coverage. The APACSDB is populated by the UEs in coverage in a crowd-sourced manner. The APACSDB stores operating frequency information mapped to location information for the UEs in coverage. In other words, the UEs report their locations and operating frequencies (e.g., frequencies currently used for communication) to the network to populate the APACSDB. The APACSDB 570 aggregates and stores crowdsourced frequency and location information on a per-cell basis and on a per-PLMN basis. The APACSDB 570 may also store location and / or frequency information mapped to the MCC.

[0050] For each cell, the APACS database 570 stores frequencies on a per PLMN / RAT basis (referred to as PLMN / RAT / FREQ) in an area (e.g., location range) associated with the cell. When the search frequency / band update circuitry 540 acquires a cell to identify frequencies that should be included in the set of frequencies searched in the SLS 552, the search frequency / band update circuitry may acquire cell-level frequency information. In some instances, the application processor 590 may query the APACS database 570 in response to acquiring a new UE location or when the UE is powered on, switched out of airplane mode, or a different SIM card is installed. The application processor 590 may then push the retrieved cell-level frequency information to the search frequency / band update circuitry 540, which uses the information to update (e.g., enhance or replace) the set of frequencies used for the SLS 552.

[0051] The APACS database 570 may also store comprehensive PLMN / RAT / FREQ for an area larger than a single cell, such as an entire country. When the UE is connected to a PLMN, the search frequency / band update circuit 540 may trigger the application processor 590 to obtain this comprehensive list of frequency information for the PLMN from the APACS database 570. In one example, the search frequency / band update circuit 540 includes some or all of the frequencies in the comprehensive list in the SLS 552 to increase the likelihood of a successful search. In other examples, the comprehensive set of PLMN frequencies is grouped in a frequency set separate from the SLS, and the frequency set is searched using a search pattern as described for the DBS and RBS.

[0052] When the UE detects that it is adjacent to a cell in a different country (e.g., with a different MCC), the search frequency / band update circuit 540 can trigger the application processor 590 to obtain the frequencies mapped to the MCC of the neighboring country from the APACSDB 570 and include these frequencies in the DBS-MCC frequency set.

[0053] In some examples, the application processor provides PLMN / RAT / FREQ for all PLMNs and RATs, and the search frequency / band update circuit 540 filters the information and selects the frequency associated with the PLMN / RAT currently used by the UE. In other examples, the application processor 590 performs the filtering on the data retrieved from the APACSDB 570.

[0054] Fig. 6A 6 is a flow chart outlining an example method 600 for performing a cell search while in an OOC state. The method 600 may be implemented, for example, in a UE. Figures 1 to 5In some examples, the UE includes: a memory storing executable instructions for executing the method 600; and a baseband processor configured to execute the instructions to perform a cell search.

[0055] The method 600 includes configuring a cell search pattern at 610, the cell search pattern defining a series of scheduled search instances for each of one or more frequency sets. The timing of the series of scheduled search instances is based on the time when the UE enters the OOC state. The cell search pattern is configured so that a corresponding minimum search rate for the corresponding frequency set is performed. At 620, the method includes performing a search for the frequency set based on the configured cell search pattern. FIG. 3A to FIG. 3C An example cell search pattern is illustrated in Figure 2 An example timer algorithm implementing the cell search mode is illustrated in .

[0056] In some examples, the method includes configuring a cell search mode using a cell search mode configuration, the cell search mode configuration including corresponding pattern parameters for each frequency set, the pattern parameters indicating one or more of: an initial gap time between scheduled search instances; a maximum gap time between scheduled search instances based on a minimum search rate for the frequency set; an increment by which the gap between scheduled search instances is increased; or a multiplier to be applied to the increment for each consecutive scheduled search instance. Figure 2 An example timer algorithm for configuring a cell search mode based on these mode parameters is illustrated in FIG.

[0057] In some examples, the method includes configuring a cell search mode based on a power state of the UE. Preconfigured or default cell search mode parameter values ​​may be adjusted based on real-time operating conditions of the UE, such as a power level of the UE when the UE loses coverage or the UE enters a low power mode (LPM) when the UE is in OOC. Definitions of different search phases (see, e.g., Figure 3A ). For example, the wait time may be set to a maximum value when the UE has full power when the UE loses coverage, and the wait time may be set to a proportionally lower value when the UE has less than full power when the UE loses coverage. This maximizes the amount of time the UE performs a more aggressive cell search to regain coverage when the UE has sufficient power to regain coverage. When the UE enters LPM, to further save power, the gap time increment value and / or the gap time increment multiplier value of selected timers or all timers may be increased to reduce the frequency of cell searches.

[0058] In some examples, the method includes configuring different cell search modes for a static UE state and a moving UE state. The motion state of the UE may be received from an application processor or determined by a baseband processor based on sensor data. Generally speaking, when the UE is in motion, the cell search mode parameter value may be lower, resulting in more frequent searches. In some examples, the cell search mode parameter value for the motion state may be half of the corresponding value for the static state.

[0059] In some examples, the method includes adjusting a cell search mode in response to detecting a WiFi connection for the UE. The WiFi connection may indicate that the UE is operating within a limited location range (inside a building). Recognizing this concept, when a WiFi connection is detected, the cell search parameters may be adjusted to achieve a reduced search rate. For example, when a WiFi connection is detected, the timer algorithm may use a cell search mode parameter value associated with a static state rather than a parameter value associated with a motion state, and / or the gap time increment may be increased, such as by changing the value of the gap time increment multiplier.

[0060] In some examples, the method includes adjusting the cell search mode in response to detecting that the UE is operating in LPM.The gap time increment value and / or the gap time increment multiplier value of the selected timer or all timers may be increased to reduce the frequency.

[0061] In some examples, the method includes adjusting the cell search mode based on the movement rate of the UE. The gap time increment value of the motion state can be adjusted inversely proportional to the change in the movement rate of the UE, so that when the movement rate increases, the gap time increment decreases and the search rate increases, and when the movement rate decreases, the gap time increment increases and the search rate decreases.

[0062] In some examples, the cell search pattern includes more than one time phase, such that during each time phase, the cell search pattern schedules search instances of the selected set of frequencies according to a different pattern than in other time phases. The cell search pattern can be configured by a configurable waiting time parameter (see, e.g. Figure 3A ) to control the respective lengths of more than one time period. When the UE loses coverage, the value of the waiting time parameter may be adjusted based on the power state of the UE. For example, the waiting time may be set to a maximum value when the UE has full power when the UE loses coverage, and the waiting time may be set to a proportionally lower value when the UE has less than full power when the UE loses coverage. This maximizes the amount of time the UE performs a more aggressive cell search to regain coverage when the UE has sufficient power to regain coverage.

[0063] In some examples, the method includes triggering a cell search for a particular set of frequencies in response to a triggering event (see, e.g. Figure 3C and Figure 4 ). In these examples, the method may include, in response to a trigger event occurring at an offset time before a scheduled search instance, determining whether a previous trigger event occurred within a trigger interval. The method includes if a previous trigger event did not occur: performing a search for at least one frequency set in the frequency set associated with the trigger event; and adjusting the timing of the scheduled search instance for at least one frequency set in the frequency set based on the offset time, while retaining the original interval between the scheduled search instances for at least one frequency set in the frequency set. This maintains the minimum search rate configured by the maximum gap time. The trigger event may be screen unlocking, transitioning from screen sleep to screen wakeup, transitioning from a UE sleep state to an awake state, detecting an unknown frequency band, or detecting a neighboring geographic boundary. Other trigger events may trigger a self-organizing cell search.

[0064] In some examples, such as Figure 5 As illustrated in the method, the method includes modifying the frequencies included in the corresponding frequency set based on information received from an application processor (AP) assisted cell search (APACS) database, which application processor (AP) assisted cell search (APACS) database stores operating frequency information mapped to location information for UEs within coverage.

[0065] In some examples, the method includes obtaining (e.g., from a database) or receiving an indication of frequencies supported in one or more cells adjacent to the UE, and modifying the frequencies included in the one or more frequency sets based on the indication of the frequencies. The method may include obtaining cell-level frequency information when the UE acquires a cell, moves to a new location, switches out of airplane mode, or installs a new SIM card. The retrieved cell-level frequency information may be used to update (e.g., enhance or replace) a frequency set for SLS.

[0066] In some examples, the method includes obtaining or receiving an indication of frequencies supported in a larger set of cells proximate to the UE, such as an entire country or region. The method may include obtaining a comprehensive list of the frequency information and including some or all of the frequencies in the comprehensive list in the SLS to increase the likelihood of a successful search. In other examples, the comprehensive set of frequencies is grouped in a frequency set separate from the SLS, and the frequency set is searched using a search pattern as described for the DBS and RBS.

[0067] In some examples, the method includes obtaining frequencies mapped to MCCs of neighboring countries and including these frequencies in the DBS-MCC frequency set.

[0068] Figure 6B 6 is a flow chart outlining an example method 650 for performing a cell search while in an OOC state. The method 650 may be implemented, for example, in a UE. Figures 1 to 5 In some examples, the UE includes: a memory storing executable instructions for executing method 650; and a baseband processor configured to execute the instructions to perform a cell search.

[0069] The method includes performing a search for one or more frequency sets based on a cell search pattern defining a series of scheduled search instances for each of the one or more frequency sets at 660. At 670, the method includes modifying frequencies included in the corresponding frequency sets based on information received from an application processor database storing operating frequency information mapped to location information for in-coverage UEs.

[0070] In some examples, such as Figure 5 As illustrated in the method, the method includes modifying the frequencies included in the corresponding frequency set based on information received from an application processor (AP) assisted cell search (APACS) database, which application processor (AP) assisted cell search (APACS) database stores operating frequency information mapped to location information for UEs within coverage.

[0071] In some examples, the method includes obtaining (e.g., from a database) or receiving an indication of frequencies supported in one or more cells adjacent to the UE, and modifying the frequencies included in the one or more frequency sets based on the indication of the frequencies. The method may include obtaining cell-level frequency information when the UE acquires a cell, moves to a new location, switches out of airplane mode, or installs a new SIM card. The retrieved cell-level frequency information may be used to update (e.g., enhance or replace) a frequency set for SLS.

[0072] In some examples, the method includes obtaining or receiving an indication of frequencies supported in a larger set of cells proximate to the UE, such as an entire country or region. The method may include obtaining a comprehensive list of the frequency information, and including a subset or all of the frequencies in the comprehensive list in the SLS to increase the likelihood of a successful search. In other examples, the comprehensive set of frequencies is grouped in a frequency set separate from the SLS, and the frequency set is searched using a search pattern as described for the DBS and RBS.

[0073] In some examples, the method includes obtaining frequencies mapped to MCCs of neighboring countries and including these frequencies in the DBS-MCC frequency set.

[0074] As can be seen from the previous description, a cell search mode that can be configured relative to the time when the UE loses coverage is provided, while also supporting self-organizing triggering of cell search and dynamic updating of the search frequency / band, which can increase the possibility of the UE regaining coverage in a power-efficient manner.

[0075] Above are several descriptions of flowcharts outlining example methods and exchanges of messages. In this specification and the appended claims, the use of the term "determine" in reference to some entities (e.g., parameters, variables, etc.) when describing method steps or functions is interpreted broadly. For example, "determine" is interpreted to cover communications such as receiving and parsing an encoded entity or value of an entity. "Determine" should be interpreted to cover accessing and reading a memory (e.g., a lookup table, a register, a device memory, a remote memory, etc.) that stores an entity or a value for an entity. "Determine" should be interpreted to cover calculating or deriving an entity or a value of an entity based on other quantities or entities. "Determine" should be interpreted to cover any way of inferring or identifying an entity or a value of an entity.

[0076] As used herein, the term "identification" when used with reference to an entity or a value of an entity is to be broadly interpreted to cover any manner of determining an entity or a value of an entity. For example, the term "identification" is to be interpreted to cover communications such as receiving and parsing an encoded entity or a value of an entity. The term "identification" should be interpreted to cover accessing and reading a memory storing an entity or a value for an entity (e.g., a device queue, a lookup table, a register, a device memory, a remote memory, etc.).

[0077] As used herein, the term "encode" when used with reference to some entity or value of an entity is to be broadly interpreted to encompass any manner or technique for generating a data sequence or signal that communicates the entity to another component.

[0078] As used herein, the term "select" when used with reference to an entity or value of an entity is to be interpreted broadly to encompass any manner of determining an entity or value of an entity from a plurality or a series of possible choices. For example, the term "select" is to be interpreted as encompassing accessing and reading a memory (e.g., a lookup table, register, device memory, remote memory, etc.) storing an entity or value for an entity and returning an entity or entity value from those stored. The term "select" is to be interpreted as applying one or more constraints or rules to a set of input parameters to determine an appropriate entity or entity value. The term "select" is to be interpreted broadly to encompass any manner of selecting an entity based on one or more parameters or conditions.

[0079] As used herein, the term "derive" is to be interpreted broadly when used with reference to an entity or a value of an entity. "Derivation" should be interpreted to encompass accessing and reading a memory (e.g., a lookup table, registers, device memory, remote memory, etc.) that stores some initial or base values, and performing processing and / or logical / mathematical operations on one or more values ​​to generate a derived entity or a value for an entity. The term "derive" should be interpreted to encompass calculating or measuring an entity or a value of an entity based on other quantities or entities. The term "derive" should be interpreted to encompass any way of inferring or identifying an entity or a value of an entity.

[0080] As used herein, the term "indication," when used with reference to an entity (e.g., a parameter or setting) or the value of an entity, is to be broadly interpreted to encompass any manner of conveying an entity or the value of an entity, either explicitly or implicitly. For example, bits within a sent message may be used to explicitly encode the value of an indication, or may encode an index or other indicator that is mapped to the value of an indication by a previous configuration. The absence of a field in a message may implicitly indicate the value of an entity based on a previous configuration.

[0081] Figure 7 700 according to one or more implementations described herein. The example network 700 may include UE 710-1, UE 710-2, etc. (collectively referred to as "UE 710" and individually referred to as "UE 710"), a radio access network (RAN) 720, a core network (CN) 730, an application server 740, and an external network 750.

[0082] The systems and devices of the example network 700 may operate in accordance with one or more communication standards, such as the 2nd Generation (2G), 3rd Generation (3G), 4th Generation (4G) (e.g., Long Term Evolution (LTE)), and / or 5th Generation (5G) (e.g., New Radio (NR)) communication standards of the 3rd Generation Partnership Project (3GPP). Additionally or alternatively, one or more of the systems and devices of the example network 700 may operate in accordance with other communication standards and protocols discussed herein, including future versions or generations of 3GPP standards (e.g., 6th Generation (6G) standards, 7th Generation (7G) standards, etc.), Institute of Electrical and Electronics Engineers (IEEE) standards (e.g., Wireless Metropolitan Area Networks (WMAN), Worldwide Interoperability for Microwave Access (WiMAX), etc.), and more.

[0083] As shown, UE 710 may include a smart phone (e.g., a handheld touch screen mobile computing device capable of connecting to one or more wireless communication networks). Additionally or alternatively, UE 710 may include other types of mobile or non-mobile computing devices capable of wireless communication, such as a personal data assistant (PDA), a pager, a laptop computer, a desktop computer, a wireless handheld phone, a watch, etc. In some specific implementations, UE 710 may include an Internet of Things (IoT) device (or IoT UE), which may include a network access layer designed for low-power IoT applications that utilize short UE connections. Additionally or alternatively, IoT UE may utilize one or more types of technologies such as machine-to-machine (M2M) communication or machine type communication (MTC) (e.g., to exchange data with an MTC server or other device via a public land mobile network (PLMN)), proximity services (ProSe) or device-to-device (D2D) communication, sensor networks, IoT networks, and more. Depending on the scenario, the M2M or MTC exchange of data may be a machine-initiated exchange, and the IoT network may include IoT UEs (which may include uniquely identifiable embedded computing devices within the Internet infrastructure) interconnected in a transient connection. In some scenarios, the IoT UE may execute background applications (e.g., keep-alive messages, status updates, etc.) to facilitate the connection of the IoT network.

[0084] UEs 710 may communicate with each other using one or more radio channels 712. UEs 710 may communicate and establish a connection (e.g., be communicatively coupled) with a RAN 720, which may involve one or more radio channels 714-1 and 714-2, each of which may include a physical communication interface / layer.

[0085] As described herein, UE 710-1, 710-2 may store adaptive cell search instructions and include instructions for executing reference Figures 1 to 6B Information on configuration and / or instructions of the disclosed adaptive cell search technology.

[0086] As shown, UE 710 may also or alternatively be connected to access point (AP) 716 via connection interface 718, which may include an air interface that enables UE 710 to communicatively couple with AP 716. AP 716 may include a wireless local area network (WLAN), a WLAN node, a WLAN termination point, etc. Connection 718 may include a local wireless connection, such as a connection consistent with any IEEE 702.11 protocol, and AP 716 may include a wireless fidelity router or other AP. Figure 7Not explicitly depicted in FIG. 7 , the AP 716 may be connected to another network (eg, the Internet) without being connected to the RAN 720 or the CN 730 .

[0087] The RAN 720 may include one or more RAN nodes 722-1 and 722-2 (collectively, RAN nodes 722, and individually, RAN nodes 722) that enable the establishment of channels 714-1 and 714-2 between the UE 710 and the RAN 720. The RAN node 722 may include a network access point configured to provide a radio baseband function for data and / or voice connections between a user and a network based on one or more of the communication technologies described herein (e.g., 2G, 3G, 4G, 5G, WiFi, etc.). Thus, as an example, the RAN node may be an E-UTRAN Node B (e.g., an enhanced Node B, eNodeB, eNB, 4G base station, etc.), a next generation base station (e.g., a 5G base station, an NR base station, a next generation eNB (gNB), etc.). The RAN node 722 may include a roadside unit (RSU), a transmission reception point (TRxP or TRP), and one or more other types of ground stations (e.g., a ground access point). In some scenarios, the RAN node 722 may be a dedicated physical device such as a macro cell base station and / or a low power (LP) base station for providing a femto cell, a pico cell, etc. having a smaller coverage area, a smaller user capacity, or a higher bandwidth than a macro cell. In addition or alternatively, one or more of the RAN nodes 722 may be a next generation eNB (gNB), which may provide an Evolved Universal Terrestrial Radio Access (E-UTRA) user plane and control plane protocol terminals 726, 728 to the UE 710, and may be connected to a 5G core network (5GC) 730 via an NG interface 724.

[0088] Multiple RAN nodes 722 may be configured to communicate with each other via an interface 723. In a specific implementation where the system is an LTE system, the interface 723 may be an X2 interface. In an NR system, the interface 723 may be an Xn interface. The X2 interface may be defined between two or more RAN nodes 722 (e.g., two or more eNBs / gNBs or a combination thereof) connected to an Evolved Packet Core (EPC) or CN 730, or between two eNBs connected to the EPC.

[0089] As shown, RAN 720 may be connected (e.g., communicatively coupled) to CN 730. CN 730 may include a plurality of network elements 732 configured to provide various data and telecommunication services to customers / subscribers (e.g., users of UE 710) connected to CN 730 via RAN 720. In some implementations, CN 730 may include an evolved packet core (EPC), a 5G CN, and / or one or more additional or alternative types of CNs. Components of CN 730 may be implemented in one physical node or in separate physical nodes, including components for reading and executing instructions from a machine-readable or computer-readable medium (e.g., a non-transitory machine-readable storage medium).

[0090] Figure 8 A network device according to one or more implementations described herein (e.g., configured to perform Figures 1 to 6B 800 is a diagram of an example of components of a user equipment (UE) for adaptive cell search disclosed in . In some implementations, the device 800 may include application circuits 802, baseband circuits 804, RF circuits 806, front end module (FEM) circuits 808, one or more antennas 810, and power management circuits (PMC) 812 (coupled together at least as shown). The components of the illustrated device 800 may be included in a UE or a RAN node. In some implementations, the device 800 may include fewer elements (e.g., the RAN node may not utilize the application circuit 802, but instead includes a processor / controller to process IP data received from the CN or the evolved packet core (EPC)). In some implementations, the device 800 may include additional elements, such as, for example, a memory / storage device, a display, a camera, a sensor (including one or more temperature sensors, such as a single temperature sensor, multiple temperature sensors at different locations in the device 800, etc.) or an input / output (I / O) interface. In other implementations, the components described below may be included in more than one device (eg, the circuitry may be included solely in more than one device for a Cloud-RAN (C-RAN) implementation).

[0091] The application circuit 802 may include one or more application processors. For example, the application circuit 802 may include circuits such as, but not limited to, one or more single-core or multi-core processors. The processor may include any combination of general-purpose processors and special-purpose processors (e.g., graphics processors, application processors, etc.). The processor may be coupled to or may include a memory / storage device, and may be configured to execute instructions stored in the memory / storage device to enable various applications or operating systems to run on the device 800. In some specific implementations, the processor of the application circuit 802 may process IP data packets received from the EPC. In some specific implementations, the processor of the application circuit 802 stores adaptive cell search instructions and information that enable the application circuit 802 to provide location information, frequency information, UE operating parameters, and to support such as Figures 1 to 6B The adaptive cell search disclosed in .

[0092] The baseband circuit 804 may include circuits such as, but not limited to, one or more single-core or multi-core processors. The baseband circuit 804 may include one or more baseband processors or control logic components to process baseband signals received from the receive signal path of the RF circuit 806 and generate baseband signals for the transmit signal path of the RF circuit 806. The baseband circuit 804 may interact with the application circuit 802 to generate and process baseband signals and control the operation of the RF circuit 806. For example, in some specific implementations, the baseband circuit 804 may include a 3G baseband processor 804A, a 4G baseband processor 804B, a 5G baseband processor 804C, or other baseband processors 804D of other existing generations, generations under development, or generations to be developed in the future (e.g., 5G, 6G, etc.).

[0093] The baseband circuitry 804 (e.g., one or more baseband processors 804A-D) can handle various radio control functions that can communicate with one or more radio networks via the RF circuitry 806. In other implementations, some or all of the functions of the baseband processors 804A-D can be included in modules stored in the memory 804G and executed via the central processing unit (CPU) 804E. In some implementations, the baseband circuitry 804 can include one or more audio digital signal processors (DSPs) 804F.

[0094] In some implementations, the memory 804G can receive and / or store adaptive cell search instructions, which can be executed by the baseband processors 804A to 804D to perform the following steps: Figures 1 to 6B Adaptive cell search is disclosed.

[0095] The RF circuit 806 may enable communication with a wireless network through a non-solid medium using modulated electromagnetic radiation. In various specific implementations, the RF circuit 806 may include switches, filters, amplifiers, etc. to facilitate communication with the wireless network. The RF circuit 806 may include a receive signal path, which may include circuits for down-converting RF signals received from the FEM circuit 808 and providing baseband signals to the baseband circuit 804. The RF circuit 806 may also include a transmit signal path, which may include circuits for up-converting baseband signals provided by the baseband circuit 804 and providing RF output signals to the FEM circuit 808 for transmission.

[0096] In some implementations, the receive signal path of the RF circuit 806 may include a mixer circuit 806A, an amplifier circuit 806B, and a filter circuit 806C. In some implementations, the transmit signal path of the RF circuit 806 may include a filter circuit 806C and the mixer circuit 806A. The RF circuit 806 may also include a synthesizer circuit 806D for synthesizing frequencies used by the receive signal path and the mixer circuit 806A of the transmit signal path.

[0097] Examples herein may include subject matter, such as methods, means for performing actions or blocks of the methods, and at least one machine-readable medium including executable instructions that, when executed by a machine or circuit (e.g., a processor with memory, an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), etc.), cause the machine to perform actions of a method or apparatus or system for adaptive cell search according to the described specific implementations and examples.

[0098] Example

[0099] Embodiment 1 is a UE comprising a memory and a baseband processor, wherein the baseband processor is configured to, in response to entering an out-of-coverage (OOC) state when executing instructions stored in the memory, cause the UE to: configure a cell search mode, wherein the cell search mode defines a series of scheduled search instances for each frequency set in one or more frequency sets, wherein the timing of the series of scheduled search instances is based on the time when the UE enters the OOC state, and further wherein the cell search mode is configured so as to perform a corresponding minimum search rate for the corresponding frequency set; and perform at least one search of the frequency set based on the configured cell search mode.

[0100] Embodiment 2 includes the subject matter described in embodiment 1, including or omitting optional elements, wherein the cell search pattern configuration includes a corresponding pattern parameter for each frequency set, and the corresponding pattern parameter indicates one or more of the following: an initial gap time between scheduled search instances; a maximum gap time between scheduled search instances based on a minimum search rate for the frequency set; an increment by which the gap between scheduled search instances is increased; or a multiplier to be applied to the increment for each consecutive scheduled search instance.

[0101] Embodiment 3 includes the subject matter described in any one or more of embodiments 1 to 2, including or omitting optional elements, wherein the baseband processor is configured to configure the cell search mode based on the power state of the UE when executing instructions stored in the memory.

[0102] Embodiment 4 includes the subject matter described in accordance with any one or more of Embodiments 1 to 3, including or omitting optional elements, wherein the baseband processor is configured to configure different cell search modes for static UE state and moving UE state when executing instructions stored in the memory.

[0103] Embodiment 5 includes the subject matter described in any one or more of Embodiments 1 to 4, including or omitting optional elements, wherein the baseband processor is configured to adjust the cell search mode in response to detecting a WiFi connection for the UE, detecting that the UE is operating in a low power mode, or detecting that the movement rate of the UE has increased.

[0104] Embodiment 6 includes the subject matter described in any one or more of Embodiments 1 to 5, including or omitting optional elements, wherein the cell search pattern includes more than one time period, wherein during each time period, the cell search pattern schedules search instances of a selected frequency set according to a pattern different from patterns in other time periods, and further, wherein the respective lengths of the more than one time periods are controlled by a configurable waiting time.

[0105] Embodiment 7 includes the subject matter described in accordance with any one or more of Embodiments 1 to 6, including or omitting optional elements, wherein the baseband processor is configured to cause the UE to: determine whether a previous trigger event occurred within a trigger interval, and if the previous trigger event did not occur: perform a search for at least one frequency set in the frequency set associated with the trigger event; and adjust the timing of the scheduled search instance for the at least one frequency set in the frequency set based on the offset time, while retaining the original interval between the scheduled search instances for the at least one frequency set in the frequency set.

[0106] Embodiment 8 includes the subject matter described in any one or more of Embodiments 1 to 7, including or omitting optional elements, wherein the triggering event includes screen unlocking, transitioning from screen sleep to screen wake-up, transitioning from UE sleep state to wake-up state, detecting an unknown frequency band, or detecting a nearby geographic boundary.

[0107] Embodiment 9 includes the subject matter described in any one or more of embodiments 1 to 8, including or omitting optional elements, wherein the baseband processor is configured to modify the frequencies included in the corresponding frequency set based on information received from an application processor database, and the application processor database stores operating frequency information mapped to location information for UEs within coverage.

[0108] Embodiment 10 includes the subject matter described in accordance with any one or more of Embodiments 1 to 9, including or omitting optional elements, wherein the baseband processor is configured to cause the UE, when executing instructions stored in the memory, to: receive an indication of frequencies supported in one or more cells adjacent to the UE or frequencies supported in a larger set of cells adjacent to the UE; and modify frequencies included in one or more frequency sets based on the indication of the frequencies.

[0109] Embodiment 11 is a method for a user equipment (UE), the method comprising: determining that the UE has entered an out-of-coverage (OOC) state; in response, configuring a cell search mode, the cell search mode defining a series of scheduled search instances for each frequency set in one or more frequency sets, wherein the timing of the series of scheduled search instances is based on the time when the UE enters the OOC state, further wherein the cell search mode is configured so as to perform a corresponding minimum search rate for the corresponding frequency set; and searching the frequency set based on the configured cell search mode.

[0110] Embodiment 12 includes the subject matter of embodiment 11, including or omitting optional elements, wherein the cell search pattern configuration includes a corresponding pattern parameter for each frequency set, and the corresponding pattern parameter indicates one or more of the following: an initial gap time between scheduled search instances; a maximum gap time between scheduled search instances based on a minimum search rate for the frequency set; an increment by which the gap between scheduled search instances is increased; or a multiplier to be applied to the increment for each consecutive scheduled search instance.

[0111] Embodiment 13 includes the subject matter described in any one or more of Embodiments 11 to 12, including or omitting optional elements, including configuring the cell search mode based on the power state of the UE.

[0112] Embodiment 14 includes the subject matter described in any one or more of Embodiments 11 to 13, including or omitting optional elements, including configuring different cell search modes for static UE state and moving UE state.

[0113] Embodiment 15 includes the subject matter described in any one or more of Embodiments 11 to 14, including or omitting optional elements, including adjusting the cell search mode in response to detecting a WiFi connection for the UE, detecting that the UE is operating in a low power mode, or detecting that the movement rate of the UE has increased.

[0114] Embodiment 16 comprises the subject matter described in accordance with any one or more of Embodiments 11 to 15, including or omitting optional elements, wherein the cell search pattern comprises more than one time phase, wherein during each time phase, the cell search pattern schedules search instances of a selected frequency set according to a pattern different from patterns in other time phases, and wherein the method comprises controlling the respective lengths of the more than one time phases by configuring a waiting time associated with the cell search pattern.

[0115] Embodiment 17 includes the subject matter described in accordance with any one or more of Embodiments 11 to 16, including or omitting optional elements, including, in response to a trigger event occurring at an offset time before a scheduled search instance, determining whether a previous trigger event occurred within a trigger interval, and if the previous trigger event did not occur: performing a search for at least one frequency set in the frequency set associated with the trigger event; and adjusting the timing of the scheduled search instance for the at least one frequency set in the frequency set based on the offset time, while retaining the original interval between the scheduled search instances for the at least one frequency set in the frequency set.

[0116] Embodiment 18 includes the subject matter described in any one or more of Embodiments 11 to 17, including or omitting optional elements, wherein the triggering event includes screen unlocking, transitioning from screen sleep to screen wake-up, transitioning from UE sleep state to wake-up state, detecting an unknown frequency band, or detecting a nearby geographic boundary.

[0117] Embodiment 19 includes the subject matter described in any one or more of Embodiments 11 to 18, including or omitting optional elements, including modifying the frequencies included in the corresponding frequency set based on information received from an application processor database, wherein the application processor database stores operating frequency information mapped to location information for UEs within coverage.

[0118] Embodiment 20 includes the subject matter described in any one or more of Embodiments 11 to 19, including or omitting optional elements, including receiving an indication of frequencies supported in one or more cells adjacent to the UE or frequencies supported in a larger set of cells adjacent to the UE; and modifying frequencies included in one or more frequency sets based on the indication of the frequencies.

[0119] Embodiment 21 is a user equipment (UE) comprising a memory and a baseband processor, wherein the baseband processor is configured to, in response to entering an out-of-coverage (OOC) state when executing instructions stored in the memory, cause the UE to: perform at least one search for one or more frequency sets based on a cell search pattern, wherein the cell search pattern defines a series of scheduling search instances for each of the one or more frequency sets; and modify the frequencies included in the corresponding frequency sets based on information received from an application processor database, wherein the application processor database stores operating frequency information mapped to location information for in-coverage UEs.

[0120] Embodiment 22 includes the subject matter of any embodiment 21, including or omitting optional elements, wherein the baseband processor is configured to cause the UE, when executing instructions stored in the memory, to: receive an indication of a set of frequencies supported in one or more cells adjacent to the UE or a set of frequencies supported in a larger set of cells adjacent to the UE; and modify the frequencies included in at least one of the one or more frequency sets based on the frequency set.

[0121] Embodiment 23 includes the subject matter described in accordance with any one or more of Embodiments 21 to 22, including or omitting optional elements, wherein the baseband processor is configured to cause the UE to include a subset of the frequency sets in a continuous search of at least one of the one or more frequency sets when executing instructions stored in the memory.

[0122] Embodiment 24 includes the subject matter described in accordance with any one or more of Embodiments 21 to 23, including or omitting optional elements, wherein the baseband processor is configured to cause the UE, when executing instructions stored in the memory, to: obtain cell-level frequency information from the application processor database when the UE acquires a new cell, switches out of flight mode, or connects to a different SIM card; and modify the frequency included in at least one of the one or more frequency sets based on the obtained cell-level frequency information.

[0123] Embodiment 25 includes the subject matter described in accordance with any one or more of Embodiments 21 to 24, including or omitting optional elements, wherein the baseband processor is configured to cause the UE, when executing instructions stored in the memory, to: obtain from the application processor database a frequency mapped to a mobile country code of a country neighboring the UE; and modify the frequency included in at least one of the one or more frequency sets based on the obtained frequency.

[0124] Embodiment 26 is a processor configured to perform the functions or operations according to any one of Embodiments 1 to 25.

[0125] Embodiment 27 is a device comprising a memory and one or more processors according to any one of embodiments 1 to 10 and 21 to 25.

[0126] Embodiment 28 is a method for a user device, the method comprising executing functions or operations performed by one or more processors according to any one of embodiments 1 to 10 and 21 to 25.

[0127] The above description of illustrative examples, implementations, aspects, etc. of the disclosed subject matter, including what is described in the abstract, is not intended to be exhaustive or to limit the disclosed aspects to the precise forms disclosed. Although specific examples, implementations, aspects, etc. are described herein for illustrative purposes, various modifications can be considered within the scope of such examples, implementations, aspects, etc., as can be appreciated by those skilled in the relevant art.

[0128] Although the method is illustrated above and described as a series of actions or events, it should be understood that the order of such actions or events illustrated should not be interpreted as having a limiting meaning. For example, some actions can occur simultaneously with other actions or events other than those illustrated and / or described herein in different orders. In addition, all the actions shown may not be required to realize one or more aspects or embodiments disclosed herein. In addition, one or more actions in the actions shown herein can be carried out in one or more separate actions and / or stages. In some embodiments, the method shown above can be implemented in a computer-readable medium using instructions stored in a memory. Many other embodiments and variations are possible within the scope of the present disclosure protected by the claims.

[0129] The term "coupled" is used throughout the specification. The term can cover connections, communications, or signal paths that enable a functional relationship consistent with the description of the present disclosure. For example, if device A generates a signal to control device B to perform an action, then in the first example, device A is coupled to device B, or in the second example, if the intermediate component C does not substantially change the functional relationship between device A and device B so that device B is controlled by device A via the control signal generated by the device, then device A is coupled to device B through the intermediate component C.

[0130] It is understood that the use of personally identifiable information should be subject to privacy policies and practices that are generally recognized to meet or exceed industry or government requirements for maintaining user privacy. Specifically, personally identifiable information data should be managed and processed to minimize the risk of unintentional or unauthorized access or use, and the nature of the authorized use should be clearly stated to users.

Claims

1. A user equipment (UE), comprising a memory and a baseband processor, the baseband processor being configured to, in response to entering an out-of-coverage (OOC) state, cause the UE to: configuring a cell search pattern, the cell search pattern defining a series of scheduled search instances for each of one or more frequency sets, wherein the timing of the series of scheduled search instances is based on the time when the UE enters the OOC state, further wherein the cell search pattern is configured such that a respective minimum search rate for the respective frequency set is performed; and A search of the set of frequencies is performed based on the configured cell search pattern.

2. The UE of claim 1 , wherein the cell search pattern configuration comprises a corresponding pattern parameter for each frequency set, the corresponding pattern parameter indicating one or more of: an initial gap time between scheduled search instances, a maximum gap time between scheduled search instances based on a minimum search rate for the frequency set, an increment by which the gap between scheduled search instances is increased, or a multiplier to be applied to the increment for each consecutive scheduled search instance.

3. The UE of claim 1, wherein the baseband processor is configured to configure the cell search mode based on a power state of the UE when executing instructions stored in the memory.

4. The UE of claim 1, wherein the baseband processor is configured to configure different cell search modes for a static UE state and a moving UE state when executing instructions stored in the memory.

5. The UE of claim 1, wherein the baseband processor is configured to adjust the cell search mode in response to detecting a WiFi connection for the UE, detecting that the UE is operating in a low power mode, or detecting that a rate of motion of the UE has increased.

6. The UE according to claim 1, wherein the cell search pattern comprises more than one time phase, wherein during each time phase, the cell search pattern schedules a search instance of a selected frequency set according to a pattern different from patterns in other time phases, and further, wherein respective lengths of the more than one time phases are controlled by a configurable waiting time.

7. The UE of claim 1 , wherein the baseband processor is configured to, in response to a trigger event occurring at an offset time before a scheduled search instance, cause the UE to: Determine whether a previous trigger event occurred within the trigger interval, and if the previous trigger event did not occur: performing a search of at least one of the frequency sets that is associated with the triggering event; and The timing of the scheduled search instances for the at least one of the frequency sets is adjusted based on the offset time while preserving an original spacing between the scheduled search instances for the at least one of the frequency sets.

8. The UE of claim 7, wherein the triggering event comprises screen unlocking, transitioning from screen sleep to screen wakeup, transitioning from a UE sleep state to an awake state, detecting an unknown frequency band, or detecting a proximate geographic boundary.

9. The UE of claim 1, wherein the baseband processor is configured to modify the frequencies included in the corresponding frequency set based on information received from an application processor database, the application processor database storing operating frequency information mapped to location information for in-coverage UEs.

10. The UE of claim 1 , wherein the baseband processor is configured to, when executing instructions stored in the memory, cause the UE to: receiving an indication of frequencies supported in one or more cells proximate to the UE or frequencies supported in a larger set of cells proximate to the UE; and Frequencies included in one or more sets of frequencies are modified based on the indication of the frequencies.

11. A baseband processor, the baseband processor being configured to: Determining that a user equipment (UE) has entered an out-of-coverage (OOC) state; in response, configuring a cell search pattern, the cell search pattern defining a series of scheduled search instances for each of one or more frequency sets, wherein timing of the series of scheduled search instances is based on a time when the UE enters the OOC state, further wherein the cell search pattern is configured such that a respective minimum search rate for the respective frequency set is performed; as well as The UE is enabled to search the frequency set based on the configured cell search mode. 12 . The baseband processor according to claim 11 , further configured to configure the cell search mode based on a power state of the UE or a motion state of the UE.

13. The baseband processor of claim 11, further configured to adjust the cell search mode in response to detecting a WiFi connection for the UE, detecting that the UE is operating in a low power mode, or detecting that a rate of motion of the UE has increased.

14. The baseband processor of claim 11 , wherein the cell search pattern comprises more than one time phase, wherein during each time phase, the cell search pattern schedules a search instance of a selected frequency set according to a pattern different from patterns in other time phases, wherein the baseband processor is further configured to control the respective lengths of the more than one time phases by configuring a waiting time associated with the cell search pattern.

15. The baseband processor of claim 11, further configured to, in response to a trigger event occurring at an offset time prior to a scheduled search instance: Determine whether a previous trigger event occurred within the trigger interval, and if the previous trigger event did not occur: performing a search of at least one of the frequency sets that is associated with the triggering event; and The timing of the scheduled search instances for the at least one of the frequency sets is adjusted based on the offset time while preserving an original spacing between the scheduled search instances for the at least one of the frequency sets.

16. The baseband processor of claim 11, further configured to modify the frequencies included in the corresponding frequency set based on information received from an application processor database storing operating frequency information mapped to location information for in-coverage UEs.

17. A user equipment (UE), comprising a memory and a baseband processor, the baseband processor being configured to, in response to entering an out-of-coverage (OOC) state, cause the UE to: performing a search of the one or more frequency sets based on a cell search pattern, the cell search pattern defining a series of scheduled search instances for each of the one or more frequency sets; and Frequencies included in the corresponding frequency set are modified based on information received from an application processor database storing operating frequency information mapped to location information for in-coverage UEs.

18. The UE of claim 17, wherein the baseband processor is configured to, when executing the instructions stored in the memory, cause the UE to: receiving an indication of a set of frequencies supported in one or more cells proximate to the UE or frequencies supported in a larger set of cells proximate to the UE; and The frequencies included in at least one of the one or more frequency sets are modified based on the frequency set.

19. The UE of claim 17, wherein the baseband processor is configured to, when executing the instructions stored in the memory, cause the UE to: When the UE acquires a new cell, switches out of flight mode, or connects to a different SIM card, obtaining cell-level frequency information from the application processor database; and The frequency included in at least one frequency set of the one or more frequency sets is modified based on the acquired cell-level frequency information.

20. The UE of claim 17, wherein the baseband processor is configured to, when executing instructions stored in the memory, cause the UE to: Retrieving from the application processor database a frequency mapped to a mobile country code of a country neighboring the UE; and The frequencies included in at least one of the one or more frequency sets are modified based on the acquired frequencies.

Images