KR102478234B1 - Apparatus and method for serching cell in an wireless terminal - Google Patents

Abstract

An apparatus and method for cell search in a communication processor (CP) of a wireless terminal having a plurality of antennas is proposed. One of the plurality of antennas may be selected in consideration of whether at least one of the at least one secondary antenna is driven and whether a finger is allocated in the rake receiver. The plurality of antennas may include a first antenna and at least one second antenna. The cell search may be performed through the selected antenna.

Description

Cell search apparatus and method in wireless terminal {APPARATUS AND METHOD FOR SERCHING CELL IN AN WIRELESS TERMINAL}

Various embodiments of the present disclosure relate to an apparatus and method for selecting an antenna for cell search in a wireless terminal.

Efforts are being made to develop an improved 5G (5 ^th -Generation) communication system or pre-5G communication system to meet the growing demand for wireless data traffic after the commercialization of 4G (4 ^th -Generation) communication systems. . For this reason, the 5G communication system or pre-5G communication system is called a Beyond 4G Network communication system or a Post LTE system.

In order to achieve a high data rate, the 5G communication system is being considered for implementation in an ultra-high frequency (mmWave) band (eg, a 60 gigabyte (60 GHz) band). In order to mitigate the path loss of radio waves and increase the propagation distance of radio waves in the ultra-high frequency band, beamforming, massive multi-input multi-output (MIMO), and full-dimensional multiple I/O ( Full Dimensional MIMO (FD-MIMO), array antenna, analog beam-forming, and large scale antenna technologies are being discussed.

In addition, to improve the network of the system, in the 5G communication system, an evolved small cell, an advanced small cell, a cloud radio access network (cloud RAN), and an ultra-dense network , Device to Device communication (D2D), wireless backhaul, moving network, cooperative communication, Coordinated Multi-Points (CoMP), and interference cancellation etc. are being developed.

In addition, in the 5G system, advanced coding modulation (Advanced Coding Modulation: ACM) methods FQAM (Hybrid FSK and QAM Modulation) and SWSC (Sliding Window Superposition Coding), advanced access technologies FBMC (Filter Bank Multi Carrier), NOMA (non-orthogonal multiple access) and SCMA (sparse code multiple access) are being developed.

In general, a wireless terminal is required to find a cell to which it will initially access in a network, find synchronization with a neighboring cell (hereinafter referred to as “neighboring cell”) to support mobility, and measure reception quality. The wireless terminal evaluates the reception quality to determine a target cell to attempt an initial access to, or the reception quality of the current cell (hereinafter referred to as “serving cell”) and the reception quality of at least one neighboring cell It is possible to determine whether to perform handover or cell-reselection by evaluating . For example, the handover may be performed by the wireless terminal in RRC_CONNECTED mode (eg, active state), and the cell reselection may be performed by the wireless terminal in RRC_IDLE mode (eg, idle state). there is.

A wireless terminal using a single antenna will not need to select an antenna when determining a target cell to attempt an initial access or measuring reception quality for handover or cell reselection. However, in a wireless terminal using multiple antennas, which antenna is used to measure reception quality can be an important factor in determining communication quality.

For example, a wireless terminal supporting Rx diversity based on multiple antennas in a good wireless communication environment, such as a strong electric field, may have little effect on communication quality regardless of which antenna is selected. That is, when a wireless terminal uses multiple antennas, a procedure for selecting an antenna will not necessarily be required in a strong electric field environment.

However, a wireless terminal supporting receive diversity based on multiple antennas in a poor wireless communication environment, such as a weak electric field, may have a significant effect on communication quality depending on which antenna is selected. That is, when a wireless terminal uses multiple antennas, success of cell search may be determined according to the selected antenna in a weak electric field environment. For example, in the case of a wireless terminal having two antennas, when reception quality in a specific cell is measured as good by the first antenna, but reception quality in the specific cell is measured as poor by the second antenna , cell search may be successful by the first antenna, and cell search may fail by the second antenna.

As a solution to this problem, in a weak electric field environment, search performance can be improved by activating all paths obtainable by multiple antennas and performing a search corresponding to each of the paths. However, in this case, time consumed for search and power consumption may increase.

According to an embodiment of the present disclosure, an antenna selection apparatus and method for measuring signal quality in a cell selected by a wireless terminal through a search in a weak electric field environment can be provided.

According to an embodiment of the present disclosure, an apparatus and method for selecting a neighboring cell by a wireless terminal equipped with multiple antennas in a wireless communication system and selecting an antenna for measuring signal quality of the selected neighboring cell may be provided. .

According to an embodiment of the present disclosure, an apparatus and method for determining a selection time of multiple antennas in consideration of driving time of multiple antennas and previously measured signal quality for cell search in a wireless terminal having multiple antennas are provided. can do.

A wireless terminal according to an embodiment of the present disclosure includes a plurality of antennas including a primary antenna and at least one secondary antenna, and at least one of the at least one secondary antenna. A communication processor (CP) for selecting one antenna from among the plurality of antennas in consideration of whether one is driven and whether a finger is allocated in the rake receiver and performing a cell search through the selected antenna. there is.

In a cell search method in a communication processor (CP) of a wireless terminal having a plurality of antennas according to an embodiment of the present disclosure, the plurality of antennas include a first antenna and at least one second antenna. (secondary antenna), and selecting one of the plurality of antennas in consideration of whether at least one of the at least one secondary antenna is driven and whether a finger is allocated in a rake receiver; and , performing a cell search through the selected antenna.

In a cell search method in a communication processor (CP) of a wireless terminal having a plurality of antennas according to an embodiment of the present disclosure, the plurality of antennas are used when the wireless terminal is in an active state. A process of checking whether a secondary antenna of the plurality of antennas is in a driving state, and if the second antenna is not in a driving state, selecting the first antenna and performing a cell search through the first antenna, and when the second antenna is in an operating state, the plurality of antennas in consideration of whether a finger is allocated in a rake receiver and an operation state of the wireless terminal and selecting one antenna from among the plurality of antennas and performing a cell search through the selected one antenna from among the plurality of antennas.

A wireless terminal according to an embodiment of the present disclosure includes a plurality of antennas including a primary antenna used by the wireless terminal in an active state, and a communication processor (CP), ,

The communication processor checks whether a secondary antenna of the plurality of antennas is in a driving state, and if the second antenna is not in a driving state, selects the first antenna, and selects a cell through the first antenna. Search is performed, and when the second antenna is in a driving state, the rake receiver selects one antenna from among the plurality of antennas in consideration of whether a finger is allocated and an operation state of the wireless terminal, and the plurality of A cell search may be performed through the selected one of the antennas.

According to the antenna selection scheme proposed in various embodiments of the present disclosure, search time can be reduced while maintaining search performance in a weak electric field environment.

1 is a diagram illustrating a block configuration of a wireless terminal according to an embodiment of the present disclosure.
2 is a diagram illustrating a configuration of a CP included in a wireless terminal according to an embodiment of the present disclosure.
3 is a diagram illustrating an antenna selection procedure by a wireless terminal in a wireless communication system according to an embodiment of the present disclosure.
4A and 4B are diagrams illustrating a control flow in which a wireless terminal selects an antenna in a weak electric field environment according to an embodiment of the present disclosure.

Embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. However, this is not intended to limit the present disclosure to specific embodiments, and should be understood to include various modifications, equivalents, and/or alternatives of the embodiments of the present disclosure. In connection with the description of the drawings, like reference numerals may be used for like elements.

In this document, expressions such as "has" or "may have" or "includes" or "may include" indicate the presence of a corresponding feature (eg, a numerical value, function, operation, or component such as a part). indicated, and does not preclude the presence of additional features.

In this document, expressions such as “A or B”, “at least one of A and/and B” or “one or more of A or/and B” may include all possible combinations of the items listed together. For example, "A or B", "at least one of A and B" or "at least one of A or B" (1) includes at least one A, (2) includes at least one B, or (3) It may refer to all cases including at least one A and at least one B.

Expressions such as “first”, “second”, “first” or “second” used in various embodiments may modify various elements regardless of order and/or importance, and limit the elements. I never do that. The above expressions may be used to distinguish one component from another. For example, a first user device and a second user device may represent different user devices regardless of order or importance. For example, without departing from the scope of the present disclosure, a first element may be termed a second element, and similarly, the second element may also be renamed to the first element.

A component (e.g., a first component) is "(operatively or communicatively) coupled with/to" another component (e.g., a second component); When it is referred to as "connected to", it should be understood that the certain component may be directly connected to the other component or connected through another component (eg, a third component). On the other hand, when an element (eg, a first element) is referred to as being “directly connected” or “directly connected” to another element (eg, a second element), the element and the above It may be understood that other components (eg, third components) do not exist between the other components.

As used in this document, the expression "configured to" means "suitable for", "having the capacity to" depending on the situation. ", "designed to", "adapted to", "made to" or "capable of" can be used interchangeably. The term “configured (or set) to” may not necessarily mean only “specifically designed to” hardware. Instead, in some contexts, the phrase "device configured to" may mean that the device is "capable of" in conjunction with other devices or components. For example, the phrase "a processor configured (or set) to perform A, B, and C" may include a dedicated processor (eg, an embedded processor) to perform those operations, or one or more software programs stored in a memory device that executes By doing so, it may mean a general-purpose processor (eg, CPU or application processor) capable of performing corresponding operations.

Terms used in this document are only used to describe a specific embodiment, and may not be intended to limit the scope of other embodiments. Singular expressions may include plural expressions unless the context clearly dictates otherwise. All terms used herein, including technical or scientific terms, may have the same meaning as commonly understood by a person of ordinary skill in the art of the present disclosure. Terms defined in commonly used dictionaries may be interpreted as having the same or similar meanings as those in the context of the related art, and unless explicitly defined in this document, they are not interpreted in ideal or excessively formal meanings. . In some cases, even terms defined in this document cannot be interpreted to exclude embodiments of the present disclosure.

In general, in a wireless communication system, a wireless terminal may perform an access procedure for network access. As an example, an access procedure in LTE or LTE-A may proceed in the order of a cell search process, a system information acquisition process, a random access process, and a paging process.

The wireless terminal can acquire synchronization with a cell in the network through a cell search process. For example, the cell search process included in the access procedure is performed in the order of obtaining frequency and symbol synchronization for a cell, obtaining frame synchronization of a cell, and determining a physical layer cell identifier (hereinafter referred to as “cell ID”) of a cell. can proceed by The cell ID may be obtained based on a primary synchronization signal (PSS) and a secondary synchronization signal (SSS) transmitted from a cell.

The wireless terminal may acquire cell system information (CSI) through a system information acquisition process. The CSI may define information necessary for communication within a cell.

For example, in LTE, CSI may include a master information block (MIB) and a system information block (SIB). The MIB may be transmitted using a broadcasting channel (BCH), and the SIB may be transmitted using a down-link shared channel (DL-SCH).

The SIB may be defined according to the type of information it contains. For example, SIB3 may include information about cell reselection, and SIB4 to SIB8 may include information about neighboring cells. When the wireless terminal accurately decodes the CSI, it can access the cell through a random access process.

In a wireless communication system, as one method for obtaining good communication quality, a cell search and selection procedure may be performed. The cell search and selection process may be performed by a series of processes of measuring signal quality of neighboring cells and selecting at least one target cell based on the measurement result.

For example, the measurement of the signal quality is performed by receiving a reference signal such as a pilot signal transmitted by a neighboring cell, and obtaining a signal-to-noise ratio (SNR) from the received reference signal. Measuring signal quality defined by at least one of a signal-to-interference plus noise ratio (SINR), Ec/Io, received signal code power (RSCP), and the like, wherein the At least one target cell may be selected based on the measured signal quality. The terminal may select at least one neighboring cell whose signal quality that satisfies a criterion determined by the network is measured as a target cell.

Even after one cell is selected, the UE may wake up every DRX cycle from an idle state and measure the signal quality of the selected cell or neighboring cells. Based on the measured result, the terminal can determine whether to stay in the currently selected cell or reselect a cell to move to a new cell.

In an embodiment of the present disclosure, a wireless terminal using multiple antennas in a weak electric field environment performs cell search to determine a target cell to attempt an initial access to, handover to move to another cell, and cell reselection to select a new cell to access. For any one of them, a method for selecting an antenna to measure reception quality will be provided.

For example, when power is turned on, the wireless terminal measures reception quality to determine a target cell to attempt access for the first time, measures reception quality to determine handover in an active state, and performs cell reselection in an idle state. reception quality can be measured.

Therefore, in an embodiment of the present disclosure, a method for selecting one antenna for measuring reception quality for each operation situation of a wireless terminal using multiple antennas in a weak electric field environment will be provided. For example, whether a finger constituting a rake receiver in a wireless terminal is allocated may affect reception quality measurement.

For this reason, a method for selecting an antenna for each operation situation of a wireless terminal must be provided. That is, it is necessary to be able to select an antenna to measure a received signal in consideration of an initial cell search to which a finger is not assigned, an active state in which a finger is always assigned, and an idle state in which a finger is alternately assigned.

For reference, when the operating situation is in the idle state, the wireless terminal wakes up every cycle for discontinuous reception (DRX) and measures reception quality, etc., in the wake-up cycle, assigning and releasing a finger that can be repeated.

1 is a diagram illustrating a block configuration of a wireless terminal according to an embodiment of the present disclosure.

Referring to FIG. 1, a multiple antenna provided in a wireless terminal may include two antennas (ANT #1 and #2).

A radio frequency (RF) module 110 converts an RF band signal received through the multiple antennas into an intermediate frequency (IF) and transmits the converted signal to a communication processor (CP) 120. . The RF module 110 converts the IF band signal provided from the CP 120 into an RF band signal and transmits the converted signal to the multi-antenna.

The CP 120 can process voice signals and data transmitted/received through a wireless network. The CP 120 may include a communication protocol, codec, and the like. For example, the CP 120 includes session initiation protocol (SIP), session description protocol (SDP), real-time transfer protocol (RTP), real-time control protocol (RTCP), message session relay protocol (MSRP), RTSP ( A protocol defined in at least one IMS standard among real time streaming protocol) and hyper text transfer protocol (HTTP) and transmission control protocol/internet protocol (TCP/IP) may be supported.

The CP 120 includes a rake receiver including a plurality of fingers, a searcher, an analog-digital converter (ADC), a digital-analog converter (DAC), and a digital signal processor (DSP). signal processor) and the like.

The CP 120 can selectively set a communication path using the multiple antennas or connect or disconnect the communication path based on the set operation mode and handover condition.

According to an embodiment of the present disclosure, the CP 120 may perform antenna selection considering the current operating state. For example, the CP 120 may perform antenna selection for cell search, antenna selection for handover in an active state, and antenna selection for cell reselection in an idle state.

The CP 120 may select one antenna from among the multiple antennas in consideration of whether a secondary antenna constituting the multiple antennas is driven and whether a finger capable of defining a current operating state is allocated. there is. Whether the sub-antenna is driven may indicate whether a signal received through the sub-antenna can be transferred to the RF module 110 . That is, when the sub-antenna is in a driving state, the terminal can connect a path for transmitting a signal received through the sub-antenna to the RF module 110 . If the sub-antenna is not in a driving state, the terminal may not connect a path for transmitting a signal received through the sub-antenna to the RF module 110 . For example, the terminal may transmit a signal received through the sub-antenna to a rake receiver in consideration of whether the sub-antenna is driven.

The CP 120 may select an antenna to be used to perform cell search, handover, and cell reselection through the selected antenna. The operating state may determine whether to allocate fingers constituting the rake receiver. For example, if the operating state is an active state, it is determined that a finger is assigned, and if the operating state is an idle state and a cell search state, it is determined that a finger is not assigned. can

More specifically, the CP 120 may select a primary antenna constituting the multi-antenna as an antenna to be used if the secondary antenna constituting the multi-antenna is not in operation.

The CP 120 may determine a candidate antenna from among the multiple antennas when an auxiliary antenna constituting the multiple antennas is in operation and a finger is allocated. When the signal quality corresponding to the determined candidate antenna satisfies a preset reference signal quality, the CP 120 may select the determined candidate antenna as an antenna to be used. If the signal quality corresponding to the determined candidate antenna does not satisfy the preset reference signal quality, the CP 120 may select the remaining antennas excluding the candidate antennas from among the multiple antennas as antennas to be used.

In the CP 120, when an auxiliary antenna constituting the multiple antennas is in operation and a finger is not assigned, the signal quality of an antenna not selected for a preceding cell search among the multiple antennas is the antenna selected for a preceding cell search. It is possible to determine whether the signal quality of is better than at least one preset criterion.

If the signal quality of the non-selected antenna is better than the signal quality of the selected antenna by at least one predetermined criterion, the CP 120 may select the unselected antenna as the antenna to be used. However, if the signal quality of the non-selected antenna is not better than the signal quality of the selected antenna by at least one predetermined criterion, the CP 120 may select the selected antenna as the antenna to be used.

2 is a diagram illustrating a configuration of a CP included in a wireless terminal according to an embodiment of the present disclosure.

Referring to FIG. 2 , the CP 120 provided in the wireless terminal may include an antenna driving module 210 and an antenna selection module 220.

Here, “module” may refer to a unit including one or a combination of two or more of, for example, hardware, software, or firmware. The “module” may be interchangeably used with terms such as, for example, unit, logic, logical block, component, or circuit. . The “module” may be a minimum unit or a part of an integrally formed part. The “module” may be a minimum unit or part thereof that performs one or more functions. The “module” may be implemented mechanically or electronically.

For example, a “module” in an embodiment of the present disclosure is a known or to be developed application-specific integrated circuit (ASIC) chip, field-programmable gate arrays (FPGAs), or programmable logic device that performs certain operations. (programmable-logic device).

The antenna driving module 210 may designate at least two antennas constituting a multi-antenna as one main antenna and at least one sub-antenna, and control driving according to the main antenna and the at least one sub-antenna. .

The antenna selection module 220 may select an antenna to be used in consideration of a current operating state and the like so as to reduce search time while maintaining search performance in a weak electric field environment. For example, the antenna selection module 220 determines at a predetermined point in time whether or not an auxiliary antenna constituting multiple antennas is driven, and based on reception quality (RSCP, etc.) measured based on a plurality of fingers constituting a rake receiver. You can select which antenna to use at a given point in time.

According to an embodiment, the antenna selection module 220 may select an antenna to be used based on RSCP considering at least one of signal strength (RSSI) and signal quality (Ec/Io). When the antenna selected in this way is used, it is possible to select a cell by cell search, increase the search success probability by measuring signal quality of the selected cell, and reduce unnecessary cell search.

3 is a diagram illustrating an antenna selection procedure by a wireless terminal in a wireless communication system according to an embodiment of the present disclosure.

Referring to FIG. 3, in step 310, the wireless terminal determines whether the current operating state is a cell search step. For example, when the power is turned on, the wireless terminal may determine that the current operating state is a cell search step.

If the current operating state is a cell search step, the wireless terminal can select an antenna for cell search based on previously selected antenna information and RSSI of antennas constituting multiple antennas in step 320.

If the current operating state is not a cell search phase, the wireless terminal may select an antenna for handover or cell reselection based on previously selected antenna information, RSCP, and Ec/Io. An operation state for selecting an antenna for handover may be an active state. An operation state for selecting an antenna for cell reselection may be an idle state.

For example, the wireless terminal may select a candidate antenna from multiple antennas based on previously selected antenna information and RSCP in step 330, and select an antenna based on Ec/Io of the selected candidate antenna in step 340.

4A and 4B are diagrams illustrating a control flow in which a wireless terminal selects an antenna in a weak electric field environment according to an embodiment of the present disclosure.

Referring to FIGS. 4A and 4B , the wireless terminal may determine whether antenna selection is necessary in step 410 . The wireless terminal may consider the current communication environment before determining whether antenna selection is necessary. That is, the wireless terminal can determine whether antenna selection is necessary only when the current communication environment is a weak electric field.

The antenna selection may be required in an initial cell search procedure, a handover procedure, a cell reselection procedure, and the like. The initial cell search procedure may be performed when the power of the wireless terminal is turned on, the handover procedure may be performed to support mobility in an active state of the wireless terminal, and the cell reselection procedure The wireless terminal wakes up in a DRX cycle from an idle state and may be performed to search for neighboring cells. In each of the three procedures, antenna selection may have the same purpose of efficiently measuring the strength of a received signal.

The wireless terminal can determine the timing of selecting an antenna for each operating state. That is, in the idle state and the active state, an antenna can be selected while a finger is assigned, and an antenna can be selected in a state where a finger is not assigned in an initial cell search procedure.

For example, in an idle state, a wireless terminal may first select an antenna when it wakes up to check a paging indication channel (PICH) in a previous DRX cycle. Since a finger is already allocated at the time of waking up to check the PICH, the wireless terminal can acquire RSCP for each antenna. If, in order to measure the strength of the received signal, the sub-antenna is turned on at the time of turning the searcher, the wireless terminal may select the first-selected antenna. Otherwise, in order to measure the strength of the received signal, when the auxiliary antenna is turned off at the time of turning the searcher, the wireless terminal may select the main antenna.

For example, in an active state or in an initial cell search procedure, a wireless terminal may select an antenna to be used when turning a searcher to measure the strength of a received signal.

When it is time to select the antenna, the wireless terminal determines in step 412 whether a secondary antenna included in the multiple antennas is in a driving state. The sub-antenna may indicate remaining antennas, that is, antennas that are not in use, other than the primary antenna used by the wireless terminal in an active state among multiple antennas.

According to one embodiment, in an active state (for example, “Cell_DCH state”), a wireless terminal monitors signal quality (RSCP, Ec/Io, etc.) on a primary path by a primary antenna at a predetermined period, and When the signal quality according to monitoring does not satisfy a preset condition, the auxiliary antenna may be driven. The wireless terminal may measure signal quality in the main path through a finger corresponding to the main path among a plurality of fingers constituting the rake receiver. The preset condition may correspond to a situation in which measured signal quality does not satisfy a reference value. That is, when the RSCP measured for the main path is smaller than the preset reference value (RSCP_DIVON_TH) or the Ec/Io measured for the main path is smaller than the preset reference value (Ec/Io_DIVON_TH), the wireless terminal uses the secondary antenna. Operating power can be supplied. At this time, in order to supply the operating voltage to the sub-antenna, it is not necessary to check whether two conditions are satisfied.

According to one embodiment, in an idle state, a wireless terminal may determine whether to drive an auxiliary antenna based on signal quality (RSSI, etc.) on a primary path by a primary antenna in a DRX cycle. The wireless terminal may measure signal quality in the main path through a finger corresponding to the main path among a plurality of fingers constituting the rake receiver.

For example, when the wireless terminal wakes up in a DRX cycle and the RSSI measured on the primary path is smaller than the preset reference value (RSSI_DIVON_TH), the RSCP on the primary path measured in the previous DRX cycle is smaller than the preset reference value (RSCP_DIVON_TH) or the previous DRX When Ec/Io in the main path measured in a period is smaller than a preset reference value (Ec/Io_DIVON_TH), operating power may be supplied to the secondary antenna. At this time, in order to supply the operating voltage to the sub-antenna, it can be implemented by checking whether at least one condition is satisfied without checking whether all of the proposed conditions are satisfied.

According to one embodiment, in the case of an initial cell search procedure, since any of the fingers constituting the rake receiver is not allocated, the wireless terminal has a secondary antenna used in the previous activation state or a primary antenna by the current primary antenna. When the signal quality measured on the path does not satisfy a preset reference value, the auxiliary antenna may be driven.

For example, in the case of an initial cell search procedure, since RSCP cannot be measured because a finger is not assigned, the wireless terminal uses an auxiliary antenna in the previous activation state or RSSI on the current main path is less than a preset reference value (RSSI_DIVON_TH). , operating power can be supplied to the sub-antenna.

According to the above-described embodiments, a wireless terminal proposes a method of determining a driving time point for an auxiliary antenna for each operation state (active state, idle state, initial cell search, etc.).

In the above-described embodiment, it is assumed that RSSI or Ec/Io is measured or RSCP is calculated.

For example, the wireless terminal can obtain RSSI from each antenna constituting multiple antennas through an automatic gain controller (AGC). The AGC may be provided for each antenna. In general, the AGC may use RSSI measured from a corresponding received signal to control the gain of the received signal. In this case, the wireless terminal may obtain RSSI for each antenna through AGC. The wireless terminal can obtain Ec/Io by combining power values in fingers allocated for each antenna constituting multiple antennas for each antenna. The wireless terminal may calculate RSCP for each antenna constituting multiple antennas using RSSI and Ec/Io measured for each antenna.

In the following description, antennas constituting multiple antennas may be classified into a selected antenna, an unchosen antenna, a candidate antenna, or a remaining antenna. The selected antenna is selected from multiple antennas in a previous antenna selection procedure. The unselected antenna is not selected in a previous antenna selection procedure among multiple antennas. The candidate antenna is selected as a candidate prior to antenna selection among multiple antennas. The remaining antennas are antennas other than the candidate antennas among multiple antennas.

Referring to FIG. 4A, if it is determined in step 412 that the auxiliary antenna is not in a driving state, the wireless terminal can select a main antenna in step 414.

If it is determined in step 412 that the auxiliary antenna is in a driving state, the wireless terminal determines in step 416 whether a finger is assigned. If the finger is not assigned, the wireless terminal determines whether the current operating state is an idle state in step 418 .

If the current operating state is the idle state, in step 420, the wireless terminal can compare RSSI (RSSI_unchosen) from a previously unselected antenna with RSSI (RSSI_chosen) from a previously selected antenna. If RSSI_unchosen is greater than or equal to the sum of RSSI_chosen and a preset value (RSSI_HYS), the wireless terminal may select a previously unselected antenna as an antenna to be used in step 422. If the RSSI_unchosen is less than the sum of RSSI_chosen and a preset value (RSSI_HYS), the wireless terminal can select a previously selected antenna as an antenna to be used in step 424.

If the finger is allocated in step 416 or the current operating state is not an idle state in step 418, the wireless terminal can determine a candidate antenna from among multiple antennas in step 426 of FIG. 4B. However, in the case of the idle state, the wireless terminal may allocate and then release a finger for each DRX cycle.

In step 426, in order to determine the candidate antenna, the wireless terminal may compare RSCP (RSCP_unchosen) in a previously unselected antenna with RSCP (RSCP_chosen) in a previously selected antenna. When RSCP_unchosen is greater than or equal to the sum of RSCP_chosen and a preset value (RSCP_HYS), the wireless terminal may determine a previously unselected antenna as a candidate antenna. When RSCP_unchosen is smaller than the sum of RSCP_chosen and a preset value (RSCP_HYS), the wireless terminal may determine a previously selected antenna as a candidate antenna.

When the candidate antennas are determined as described above, the wireless terminal can determine whether to select the previously determined candidate antennas or remaining antennas in steps 428 to 434.

More specifically, in step 428, the wireless terminal compares Ec/Io (Ec/Io_candidate) in a candidate antenna with a preset reference value (TH1, Ec/Io_SEL_TH) to determine whether the Ec/Io_candidate is greater than the Ec/Io_SEL_TH. judge If the Ec/Io_candidate is not greater than the Ec/Io_SEL_TH, the wireless terminal can compare Ec/Io (Ec/Io_candidate) in the candidate antenna with Ec/Io (Ec/Io_remained) in the remaining antennas in step 430. If Ec/Io_candidate is less than the sum of Ec/Io_remained and a preset error reference value (Ec/Io_HYS), the wireless terminal may select the remaining antennas as the antennas to be used in step 434.

If the Ec/Io_candidate is greater than the Ec/Io_SEL_TH or the RSSI_unchosen is greater than or equal to the sum of Ec/Io_remained and a preset error reference value (Ec/Io_HYS), the wireless terminal selects a candidate antenna as the antenna to be used in step 432. can

On the other hand, in the detailed description of the present disclosure, specific embodiments have been described, but within the limit that does not deviate from the scope according to the various embodiments proposed in the present disclosure, those skilled in the art can make various modifications. Of course it can be done. Therefore, the scope according to the present disclosure should not be limited to the described embodiments and should not be defined, and should be defined by not only the scope of the claims to be described later, but also those equivalent to the scope of these claims. In addition, these modified implementations should not be individually understood from the technical spirit or perspective of the present disclosure.

Claims (20)

In a wireless terminal,
A plurality of antennas including a primary antenna and at least one secondary antenna;
Selecting one antenna from among the plurality of antennas based on whether at least one of the at least one secondary antenna is in a driving state and whether a finger is allocated in a rake receiver;
A communication processor (CP) performing cell search through the selected one antenna,
When selecting one antenna from among the plurality of antennas, the communication processor,
When at least one of the at least one second antenna is in operation and the finger is not allocated, the signal quality of an antenna not selected for a preceding cell search among the plurality of antennas is the signal quality of an antenna selected for a preceding cell search determine whether it is better than a pre-set standard,
If the signal quality of the non-selected antenna is better than the signal quality of the selected antenna by the predetermined criterion or more, selecting the non-selected antenna;
If the signal quality of the non-selected antenna is not better than the signal quality of the selected antenna by the predetermined criterion or more, select the selected antenna;
The driving state is a state in which a signal received through at least one of the at least one second antenna is transferred to the rake receiver.
The method of claim 1, wherein the communication processor,
When at least one of the at least one second antenna is in the driving state and the finger is allocated, determining a candidate antenna from among the plurality of antennas;
When the signal quality corresponding to the candidate antenna satisfies a preset reference signal quality, the candidate antenna is selected;
and if the signal quality corresponding to the candidate antenna does not satisfy the preset reference signal quality, selecting the remaining antennas excluding the candidate antenna from among the plurality of antennas.
delete The method of claim 1, wherein the communication processor,
and selecting the first antenna when the at least one second antenna is not in operation.
According to claim 1,
The selected one antenna is an antenna for measuring signal quality of at least one cell around the wireless terminal in a weak electric-field environment.
The method of claim 1, wherein the communication processor,
If the operating state is an active state, it is determined that the finger is assigned, and if the operating state is an idle state or a cell search state, it is determined that the finger is not assigned Characterized by a wireless terminal.
A cell search method of a wireless terminal having a plurality of antennas,
The plurality of antennas include a first antenna (primary antenna) and at least one second antenna (secondary antenna), and whether at least one of the at least one second antenna (secondary antenna) is in a driving state, and a rake receiver Selecting one antenna from among the plurality of antennas based on whether a finger is allocated in
A step of performing a cell search through the selected one antenna;
The process of selecting the one antenna,
When at least one of the at least one second antenna is in operation and the finger is not allocated, the signal quality of an antenna not selected for a preceding cell search among the plurality of antennas is the signal quality of an antenna selected for a preceding cell search A process of determining whether the quality is better than a preset standard;
selecting the unselected antenna when the signal quality of the non-selected antenna is better than the signal quality of the selected antenna by the preset standard or more;
and selecting the selected antenna when the signal quality of the non-selected antenna is not better than the signal quality of the selected antenna by the predetermined criterion or more,
The driving state is a state in which a signal received through at least one of the at least one second antenna is transmitted to the rake receiver.
The method of claim 7, wherein the process of selecting one antenna from among the plurality of antennas comprises:
determining a candidate antenna from among the plurality of antennas when at least one of the at least one second antenna is in the driving state and the finger is allocated;
selecting the candidate antenna when the signal quality corresponding to the candidate antenna satisfies a preset reference signal quality;
and selecting remaining antennas excluding the candidate antennas from among the plurality of antennas when the signal quality corresponding to the candidate antenna does not satisfy the preset reference signal quality.
delete The method of claim 7, wherein the process of selecting the one antenna comprises:
and selecting the first antenna if all of the at least one second antenna is not in operation.
According to claim 7,
The selected antenna is an antenna for measuring signal quality of at least one cell around the wireless terminal in a weak electric-field environment.
The method of claim 7, wherein the process of selecting the one antenna comprises:
If the operating state is an active state, determining that the finger is assigned;
and determining that the finger is not allocated when the operating state is an idle state or a cell search state.
In the cell search method of a wireless terminal having a plurality of antennas,
The plurality of antennas include a first antenna (primary antenna) and a second antenna (secondary antenna), and determining whether the second antenna is in a driving state;
selecting the first antenna and performing a cell search through the first antenna when the second antenna is not in a driving state;
When the second antenna is in a driving state, the rake receiver selects one antenna from among the plurality of antennas based on whether a finger is allocated and an operation state of the wireless terminal, and the selected one among the plurality of antennas Including the process of performing cell search through an antenna of,
The process of selecting one antenna from among the plurality of antennas,
If the finger is not assigned or the operating state of the wireless terminal is in an idle state, the signal quality corresponding to the antenna not selected for the preceding cell search among the plurality of antennas is the signal corresponding to the antenna selected for the preceding cell search A process of determining whether the quality is better than a predetermined standard or not;
selecting the unselected antenna when the signal quality corresponding to the non-selected antenna is better than the signal quality corresponding to the selected antenna by the predetermined criterion;
and selecting the selected antenna when the signal quality corresponding to the non-selected antenna is not better than the signal quality corresponding to the selected antenna by a predetermined criterion or more, and the driving state includes the step of selecting the second antenna. A cell search method in which a signal received through is transmitted to the rake receiver.
The method of claim 13, wherein the process of selecting one antenna from among the plurality of antennas comprises:
determining a candidate antenna from among the plurality of antennas when the finger is allocated or the operating state is not an idle state;
selecting the candidate antenna when the signal quality corresponding to the candidate antenna satisfies a preset reference signal quality;
If the signal quality corresponding to the candidate antenna does not satisfy the preset reference signal quality, selecting an antenna remaining excluding the candidate antenna from among the plurality of antennas
A cell navigation method comprising a.
According to claim 13,
The selected one antenna is an antenna for measuring signal quality of at least one cell around the wireless terminal in a weak electric-field environment.
The method of claim 13, wherein the process of selecting one antenna from the plurality of antennas comprises:
If the operating state is an active state, determining that the finger is assigned;
and determining that the finger is not allocated when the operating state is an idle state or a cell search state.
In a wireless terminal,
A plurality of antennas including a primary antenna and a secondary antenna;
Including a communication processor (CP: communication processor),
The communication processor,
Determine whether a second antenna of the plurality of antennas is in a driving state;
When the second antenna is not in a driving state, selecting the first antenna and performing a cell search through the first antenna;
When the second antenna is in a driving state, the rake receiver selects one antenna from among the plurality of antennas based on whether a finger is allocated and an operation state of the wireless terminal, and the selected one among the plurality of antennas configured to perform cell search through an antenna of
When selecting one antenna from among the plurality of antennas, the communication processor, if the finger is not assigned or the operating state is an idle state, a signal corresponding to an antenna not selected for a preceding cell search among the plurality of antennas determining whether the quality is better than a preset standard or higher than the signal quality corresponding to the antenna selected for the preceding cell search;
If the signal quality corresponding to the non-selected antenna is better than the signal quality corresponding to the selected antenna by the predetermined criterion or more, select the unselected antenna;
If the signal quality corresponding to the non-selected antenna is not better than the signal quality corresponding to the selected antenna by more than the preset criterion, select the selected antenna;
The driving state is a state in which a signal received through the second antenna is transferred to the rake receiver.
The method of claim 17, wherein the communication processor,
If the finger is assigned or the operating state is not an idle state, determining a candidate antenna from among the plurality of antennas;
When the signal quality corresponding to the candidate antenna satisfies a preset reference signal quality, selecting the candidate antenna;
and if the signal quality corresponding to the candidate antenna does not satisfy the preset reference signal quality, selecting remaining antennas excluding the candidate antenna from among the plurality of antennas.
According to claim 17,
The selected antenna is an antenna for measuring signal quality of at least one cell around the wireless terminal in a weak electric-field environment.
The method of claim 17, wherein the communication processor,
If the operating state is an active state, it is determined that the finger is assigned;
and determining that the finger is not assigned when the operating state is an idle state or a cell search state.

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