TW202031075A - Operating method of terminal and cell terminal and terminal - Google Patents

Abstract

An operating method of a terminal performing a cell search using first and second memories for buffering input samples includes detecting a first primary synchronization signal (PSS) group from a first input sample group while buffering the first input sample group in the first memory in a first interval. While buffering a second input sample group in the second memory in a second interval following the first interval, the method detects a second PSS group from the second input sample group, and a first secondary synchronization signal (SSS) group corresponding to the first PSS group from the first input sample group. While buffering a third input sample group in the first memory in a third interval following the second interval, the method detects a third PSS group from the third input sample group, and a second SSS group corresponding to the second PSS group from the second input sample group.

Description

Terminal and cell terminal operation method and terminal

The exemplary embodiment of the concept of the present invention relates to an operating method of a terminal device for performing effective cell search in a wireless communication system and a terminal device used in the method. [Cross reference of related applications]

This application claims that the Korean Patent Application No. 10-2018-0150086 and Korean Patent Application No. 10-2019-0043304 filed at the Korea Intellectual Property Office on November 28, 2018 and April 12, 2019, respectively The full text of the disclosure of the Korean patent application is incorporated into this application for reference.

The fifth-generation (5G) (or new radio (NR)) communication system uses new wireless access technologies. Compared with the existing long-term evolution (LTE) and advanced (advanced, A) long-term evolution (LTE-A) communication systems, the 5G communication system uses a bandwidth of about 100 megahertz (MHz) or greater An ultra-wideband of 100 MHz is used to provide ultra-high-speed data services of billions of bits per second (Gbps). However, it is difficult to ensure an ultra-wideband frequency of about 100 MHz or more in the frequency band of hundreds of megahertz or billions of hertz (GHz) used in LTE and LTE-A communication systems. For 5G communication systems, a method of transmitting signals using a wide frequency bandwidth existing in a frequency band of about 6 gigahertz or greater is being considered. In a 5G communication system, a millimeter wave band (for example, a frequency band of about 28 gigahertz or a frequency band of about 60 gigahertz) can be used to increase the transmission rate.

According to an exemplary embodiment, there is provided an operating method of a terminal set configured to perform a cell search by buffering input samples using a first memory and a second memory, the operating method including: While buffering the first input sample group in the first memory in the first interval, a first primary synchronization signal (PSS) group is detected from the first input sample group. The method further includes: while buffering a second input sample group in the second memory in a second interval after the first interval, detecting a second PSS from the second input sample group Group, and detecting a first secondary synchronization signal (SSS) group corresponding to the first PSS group from the first input sample group. The method further includes: while buffering a third input sample group in the first memory in a third interval after the second interval, detecting a third PSS from the third input sample group Group, and detecting a second SSS group corresponding to the second PSS group from the second input sample group.

According to an exemplary embodiment, there is provided an operating method of a cell terminal device equipped with a plurality of memories to alternately buffer input samples generated for cell search operations in a specific buffer interval, the operation The method includes: buffering a first input sample group for performing a first valid cell search operation in a first interval in a first memory; and a second memory after the first interval in a second memory Buffer the second input sample group used for the second effective cell search operation in the second interval. The first effective cell search operation is performed using the first input sample group in a first search interval including the first interval and the second interval.

According to an exemplary embodiment, a terminal includes: a buffer divided into a first memory and a second memory for alternately buffering input samples generated for a cell search operation in a specific buffer interval; And the baseband processor is configured to control the first effective cell search operation performed by the first input sample group buffered in the first memory in the first interval during the first search interval, so The first search interval includes the first interval and a second interval after the first interval. The second input sample group for performing the second effective cell search operation in the second interval is buffered in the second memory.

Hereinafter, exemplary embodiments of the inventive concept will be explained more fully with reference to the accompanying drawings. In all figures, the same reference numbers may refer to the same elements. It should be understood that the terms “first”, “second”, “third”, etc. are used herein to distinguish various elements, and the elements are not limited by these terms. Therefore, the “first” element in an exemplary embodiment may be described as a “second” element in another exemplary embodiment.

FIG. 1 is a block diagram of a wireless communication system 1 according to an exemplary embodiment of the inventive concept. FIG. 2 is a diagram showing synchronization signals including synchronization signal blocks (SSB) used during cell search.

As shown in FIG. 1, the wireless communication system 1 may include a first cell 10, a second cell 20 and a third cell 30 and a terminal 100. The cells 10, 20, and 30 may be, for example, cellular towers. For ease of description, the wireless communication system 1 is shown as including only three cells (10, 20, and 30). However, the exemplary embodiments of the inventive concept are not limited to this. For example, in an exemplary embodiment, the wireless communication system 1 may be implemented to include more than three cells (10, 20, and 30) or less than three cells (10, 20, and 30).

The terminal 100 can be connected to the wireless communication system 1 by transmitting and receiving signals to and from the first cell 10, the second cell 20, and the third cell 30 and from the first cell 10, the second cell 20, and the third cell 30. The wireless communication system 1 to which the terminal 100 can be connected may include a system using radio access technology (RAT), and may include, for example, a wireless communication system using a cellular network, such as a fifth-generation (5G) communication system , Long-term evolution (LTE) communication system, advanced (A) long-term evolution (LTE-A) communication system, code division multiple access (CDMA) communication system and global system for mobile communication , GSM) communication system; or wireless local area network (WLAN) communication system; or other wireless communication systems. In the following, description will be made assuming that the wireless communication system 1 to which the terminal 100 is connected is a 5G communication system. However, the exemplary embodiment of the inventive concept is not limited to this, and the exemplary embodiment can be applied to the next generation wireless communication system.

In the 5G communication system, because of the use of beam forming techniques to increase the reach of radio waves, it is not only necessary to search for cells that can provide good communication services in the cell search operation of the terminal, but also Searching for a transmission beam matching the reception beam of the terminal set among a plurality of transmission beams formed by the cell. Therefore, to achieve this goal, the number of input samples of the synchronization signal to be buffered by the terminal is greatly increased. Therefore, the available memory space for data processing operations other than the cell search operation of the terminal may be limited, and therefore, the overall performance of the terminal may be reduced. The exemplary embodiments of the inventive concept aim to utilize available memory space in a more efficient manner, as explained in detail below.

The wireless communication network of the wireless communication system 1 can support the communication of multiple wireless communication devices including the terminal 100 by sharing available network resources. For example, in a wireless communication network, the following multiple connection methods can be used to transfer information: such as CDMA, frequency division multiple access (FDMA), time division multiple access (TDMA) ), orthogonal frequency division multiple access (OFDMA), single carrier frequency division multiple access (SC-FDMA), OFDM-FDMA, OFDM-TDMA and OFDM-CDMA .

The first cell, the second cell, and the third cell (10, 20, and 30) generally refer to fixed stations that communicate with the terminal 100 and/or other cells, and can be used to communicate with the terminal 100 and other cells. The community communicates to exchange data and control information. For example, each of the first cell 10, the second cell 20, and the third cell 30 may refer to a base station, a Node B, an evolved-Node B (evolved-Node B, eNB), and a next-generation node. B (next generation node B, gNB), sector (sector), site (site), base transceiver system (BTS), access point (AP), relay node (relay node) ), remote radio head (remote radio head, RRH), radio unit (RU), small cell (small cell), etc. In this specification, a cell or a base station can be interpreted in a broad sense to mean a base station controller (BSC) in CMDA, a wideband code division multiple access (WCDMA) A certain area or function covered by Node B, evolved Node B (eNB) or sector in LTE, and can cover all kinds of coverage areas, such as (for example) megacell, macrocell, Microcell, picocell, femtocell, relay node, RRH, RU and small cell communication range.

The terminal 100 can be fixed or mobile as user equipment (UE), and can refer to any device capable of communicating with a cell to send and receive data and/or control information to or from the cell. For example, the terminal 100 can be called a mobile station (mobile station, MS), mobile terminal (MT), user terminal (UT), subscriber station (SS), Smart phones, wireless devices, handheld devices, etc.

1, the first cell 10, the second cell 20, and the third cell 30 can be connected to the terminal 100 via a wireless channel and can provide various communication services. The first cell 10, the second cell 20, and the third cell 30 can serve all user traffic via a shared channel and can collect status information (for example, the buffer status of the terminal 100) , Available transmission power status and channel status) to implement scheduling (scheduling). The wireless communication system 1 can support beamforming technology by using OFDM as the radio access technology. In addition, the wireless communication system 1 can support an adaptive modulation and coding (AMC) method to determine the modulation scheme and channel coding rate according to the channel state of the terminal 100.

The wireless communication system 1 can transmit and receive signals by using a wide frequency band existing in a frequency band of about 6 gigahertz or greater. For example, in the wireless communication system 1, the data transmission rate can be increased by using a millimeter wave frequency band (for example, a frequency band of about 28 gigahertz or a frequency band of about 60 gigahertz). In this case, the millimeter wave band can support directional beam-based transception by using multiple antennas to ensure coverage, because the signal attenuation relative to the distance is relatively large. The wireless communication system 1 can perform a beam sweeping operation for transmission and reception based on directional beams.

The beam scanning may be that the terminal 100 and the first cell 10, the second cell 20, and the third cell 30 sequentially or randomly scan the directional beams with a specific pattern to determine the transmit beams and the receive beams with mutually modulated directional directions. the process of. For example, the pattern of the transmit beam and the pattern of the receive beam having directional directions tuned to each other may be determined as a pair of transmit/receive beam patterns. The beam pattern may be the shape of the beam determined by the width and direction of the beam. In the following, exemplary embodiments are mainly explained for a situation in which the terminal device 100 performs cell search, and it is assumed that the first cell, the second cell, and the third cell (10, 20, and 30) pass through multiple cells having different beam patterns. The two transmit beams transmit synchronization signals to the terminal 100, and each of the synchronization signals includes an SSB for cell search. As an example, the first cell 10 may transmit synchronization signals each including an SSB for cell search to the terminal 100 via the first transmission beam TX_B1 to the eighth transmission beam TX_B8. However, it should be understood that FIG. 1 is only an example for ease of understanding, and the exemplary embodiment is not limited to this, and various situations may occur according to the communication environment or communication conditions of the wireless communication system 1.

1 and 2, for example, the first cell 10 may include any one of the first synchronization signal block (SSB) SSB1 to the eighth SSB SSB8 via the first transmit beam TX_B1 to the eighth transmit beam TX_B8. The synchronization signal of the user is transmitted to the terminal 100. For example, the first cell 10 may transmit a signal including the first SSB SSB1 to the terminal 100 via the first transmit beam TX_B1, transmit the signal including the second SSB SSB2 to the terminal 100 via the second transmit beam TX_B2, etc. Wait. In this way, the first cell 10 can transmit the first SSB SSB1 to the eighth SSB SSB8 to the terminal 100 via the first transmit beam TX_B1 to the eighth transmit beam TX_B8, and the terminal 100 can use the first SSB SSB1 To any one of the eighth SSB SSB8 to search the first cell 10.

As shown in Figure 2, the SSB may include a primary synchronization signal PSS, an auxiliary synchronization signal SSS, and a physical broadcast channel (physical broadcast channel) PBCH. In an exemplary embodiment, the SSB may include four symbols, and the main synchronization signal PSS, the auxiliary synchronization signal SSS, and the physical broadcast channel PBCH may be located at positions corresponding to the specific resource block RB in the direction of the frequency axis. In addition, one resource block RB may include 12 consecutive subcarriers. As an example, the primary synchronization signal PSS corresponding to the first symbol can be transmitted to the terminal 100 via 127 subcarriers.

In an exemplary embodiment, two SSBs may be located in one slot, and the first cell 10 may transmit the _SSB burst set to the terminal 100 in a specific SSB burst set period (burst set period) T _SSB . For example, assuming that the wireless communication system 1 is a new radio (NR) with a subcarrier spacing of about 15 kHz, the first cell 10 may include the first SSB SSB1 to the eighth during the SSB burst set period T _SSB. The SSB burst set of SSB SSB8 is transmitted to the terminal 100. In this case, the length of one slot may be about 1 millisecond, and the SSB burst collection period T _SSB may be about 20 milliseconds. However, the exemplary embodiment is not limited to this, and the number of SSBs included in the SSB burst set, the SSB burst set period T _SSB, and the length of one slot may be used in the first cell 10 according to, for example, the size of the subcarrier spacing. The period of the synchronization signal set in, the time interval allocated for cell search, etc. change.

For example, the first SSB SSB1 to the eighth SSB SSB8 can be transmitted to the terminal 100 via the first transmit beam TX_B1 to the eighth transmit beam TX_B8 of the first cell 10, and in this way, the second cell 20 The third cell 30 and the third cell 30 can also transmit the synchronization signal including the SSB used by the terminal 100 to search the second cell 20 and the third cell 30 to the terminal 100 via the multiple transmit beams.

The terminal 100 according to an exemplary embodiment of the concept of the present invention can receive synchronization signals from the first cell 10, the second cell 20, and the third cell 30, generate multiple input samples by sampling the synchronization signals, and The samples are divided into specific input sample groups to perform effective cell search operations on each input sample group. The multiple input samples may include multiple primary synchronization signals PSS, multiple secondary synchronization signals SSS, and multiple physical broadcast channels PBCH received from each of the first cell 10, the second cell 20, and the third cell 30 . The terminal 100 can perform a valid cell search operation for each input sample group by using multiple memories of the terminal 100 to perform multiple buffering operations on the multiple input samples. The following describes the details of the effective cell search operation for each input sample group and the multiple buffering operations performed on the input samples of the terminal 100.

FIG. 3 is a block diagram showing in detail the terminal 100 according to an exemplary embodiment of the inventive concept.

3, the terminal 100 may include multiple antennas 110, a front-end circuit 120, a transceiver 130, and a controller 140. The multiple antennas 110 can be connected to the front-end circuit 120 and can transmit signals provided by the front-end circuit 120 to other wireless communication devices (terminals or cells), or provide signals received from the other wireless communication devices to the front-end circuit 120. In an exemplary embodiment, the terminal 100 may use the multiple antennas 110 to support a phased array (phased array), multiple-input and multiple-output (MIMO), etc. The front-end circuit 120 may include an antenna tuner, and the antenna tuner may be connected to the plurality of antennas 110 to adjust the impedance of the plurality of antennas 110.

The transceiver 130 may include a receiver 131, a transmitter 132, and a switch 133. The receiver 131 may process the radio frequency (RF) reception signal received from the switch 133 to generate a base frequency reception signal. As an example, the receiver 131 may include a filter, a mixer, a low noise amplifier, and the like. The receiver 131 may process the synchronization signal of the RF frequency band received from the switch 133 to generate a base frequency synchronization signal, and the base frequency synchronization signal may be provided to the controller 140. The transmitter 132 can generate an RF transmission signal by processing the baseband transmission signal received from the controller 140. The transmitter 132 may include, for example, a filter, a mixer, a power amplifier, and the like.

The controller 140 may include a cell searcher 142, and the cell searcher 142 may include a synchronization signal (SS) detector 142a and a buffer 142b. The components included in the controller 140 may be implemented as dedicated hardware blocks designed by using logic synthesis or the like, or may be implemented as at least one processor and include a software area executed by the at least one processor Block processing unit, and can be implemented as a combination of dedicated hardware block and processing unit. In this specification, the controller 140 may refer to a device for efficiently performing cell search.

The cell searcher 142 can perform a cell search operation and can allow the terminal 100 to connect to the wireless communication system 1 via the searched cell and perform wireless communication. The synchronization signal detector 142a can perform an effective cell search operation on each input sample group by dividing a plurality of input samples generated by sampling the baseband synchronization signal into input sample group units. When performing a valid cell search operation, the synchronization signal detector 142a can use the multiple memories MEM of the buffer 142b to perform multiple buffering for multiple input samples.

For example, the multiple memories MEM of the buffer 142b can alternately buffer the input samples in the input sample group unit. For example, an input sample group with an odd number of turns may be buffered in the first memory of the plurality of memories MEM, and an input sample group with an even number of turns may be in the plurality of Buffering is performed in the second memory of the memory MEM. This will be further explained with reference to FIG. 4. The multiple memories MEM of the buffer 142b can be physically separated or virtually divided by address management. The effective cell search operation can refer to the following series of operations: use the input samples included in an input sample group to detect the primary synchronization signal PSS group and the auxiliary synchronization signal SSS group; and use the detected primary synchronization signal PSS The group and the auxiliary synchronization signal SSS group determine the effective cell.

The terminal 100 according to the exemplary embodiment of the inventive concept can efficiently use the memory by using multiple memories to perform multiple buffering on the input samples in the input sample group unit, and can efficiently use the memory by The group performs an effective cell search operation to perform a prompt cell search (prompt cell search).

FIG. 4 is a diagram for explaining a multiple buffering operation according to an exemplary embodiment of the inventive concept. FIG. 5 is a block diagram of the synchronization signal detector 142a according to an exemplary embodiment of the inventive concept. In FIG. 4, it is assumed that the buffer for buffering the input samples of the terminal 100 includes a first memory and a second memory.

4, in a specific buffer interval BF_ITV, the multiple input samples can be divided into input sample groups, and can be alternately buffered in the first memory and the second memory. The buffer interval BF_ITV can be set to match the SSB burst set period T _SSB shown in FIG. 2. In addition, each length of the first interval 1 ^st ITV to n ^th ITV can be determined according to the number of input samples included in the first input sample group 1 ^st ISG to the n th input sample group n ^th ISG . The plurality of input samples may be divided into a first input sample group 1 ^st ISG to an n ^th input sample group n ^th ISG, and in the first interval 1 ^st ITV to the n ^th interval n ^th ITV in the first memory Alternate buffering is performed in the memory and the second memory.

For example, the first input sample group 1 ^st ISG can be buffered in the first memory in the first interval 1 ^st ITV, and the second input sample group can be buffered in the second memory in the second interval 2 ^nd ITV Group 2 ^nd ISG, and the third input sample group 3 ^rd ISG can be buffered in the first memory in the third interval 3 ^rd ITV. In an exemplary embodiment, the first memory and the second memory may have a capacity sufficient to buffer an input sample group, and when a new input sample group is to be buffered, the previously stored input sample group can be deleted. Although FIG. 4 shows an exemplary embodiment in which the buffer interval BF_ITV is divided into the first interval 1 ^st ITV to the n ^th interval n ^th ITV having the same length, the exemplary embodiment is not limited to this. For example, in an exemplary embodiment, the length of the first interval 1 ^st ITV to the nth interval n ^th ITV may vary according to the environment, performance, workload, etc., and a detailed example thereof is referred to FIGS. 14A to 14D Examples are described.

5, the synchronization signal detector 142a may include a PSS detector 142a_1, an SSS detector 142a_2, and a timing controller 142a_3. The PSS detector 142a_1 can perform the PSS detection operation in the input sample group unit. The PSS detector 142a_1 can calculate the degree of association between the input samples of the input sample group and the PSS-based sequence, and determine the PSS group from the input sample group based on the calculated association result. The PSS group may indicate a unit including input samples corresponding to a good candidate PSS for cell search from a specific input sample group. For example, the PSS detector 142a_1 can calculate the degree of correlation between the target input sample and the corresponding PSS-based sequence, and when the calculated correlation result is equal to or greater than the first reference value, the target input sample can be determined as PSS group. The PSS detector 142a_1 can perform the operation of determining the PSS group in parallel with the operation of buffering the input sample group in a specific memory.

The SSS detector 142a_2 can select any one of the input samples of the PSS group detected by the PSS detector 142a_1, set the SSS configuration based on the information obtained from the selected input sample, and set the SSS configuration based on the set The SSS configuration performs the operation of detecting the SSS corresponding to the selected input sample at least once to determine the SSS group. The SSS group may indicate a unit including input samples corresponding to good candidate SSSs for cell search from a specific input sample group. The information obtained from the selected input sample may include the specific timing (for example, 5 millisecond timing) of the cell corresponding to the selected input sample, the primary identification number (PID) of the cell, the location of the SSS, etc.

The SSS detector 142a_2 can set the SSS configuration based on the information obtained from the selected input sample, and generate the SSS-based sequence based on the set SSS configuration. The SSS detector 142a_2 may calculate the degree of association between the generated SSS-based sequence and the input samples of the input sample group, and determine the SSS group from the input sample group based on the calculated association result. For example, the SSS detector 142a_2 may calculate the degree of association between the target input sample and the corresponding SSS-based sequence, and when the calculated association result is equal to or greater than the second reference value, the target input sample may be determined as SSS group. The SSS detector 142a_2 can use the input sample group stored in the specific memory to perform the operation of determining the SSS group.

The timing controller 142a_3 can control the operation timing of the PSS detector 142a_1 and the SSS detector 142a_3 according to the buffer status of the buffer 142b of the terminal 100 (see FIG. 3). In an example, the timing controller 142a_3 can provide the first timing control signal TM_C1 to the PSS detector 142a_1, and can control the PSS detection while buffering the input sample group in the memory of the buffer 142b (see FIG. 3). The detector 142a_1 uses the sample group to perform the PSS detection operation. In addition, the timing controller 142a_3 can control the SSS detector 142a_2 to use the storage in the memory after completing the SSS configuration by providing the second timing control signal TM_C2 to the SSS detector 142a_2 based on the information obtained from the PSS group SSS detection operation is performed on the input sample group in.

In addition, the timing controller 142a_3 can control the memory to complete the SSS detection operation of the input sample group (or use the effective cell search operation of the input sample group) before the memory storing the input sample group buffers the new input sample group. . In an exemplary embodiment, the timing controller 142a_3 may pre-set the number of input samples (or PSS) of the PSS group, or perform detection of the number of input samples (or PSS) of the PSS group of the SSS group. limit. This will be further explained with reference to FIG. 7.

6 is a flowchart illustrating an operation method of the cell searcher 142 according to an exemplary embodiment of the concept of the present invention. 6 is explained with reference to the configuration of the terminal 100 shown in FIG. 3. In addition, suppose "N" is the number of input samples included in an input sample group, "h" is the ordinal number of the input sample group, "i" is the ordinal number of the input sample included in the input sample group, " K" is the ordinal number of input samples determined based on all input samples, and "M" is the number of all input samples.

6, the cell searcher 142 may receive the i-th input sample (S100) and determine whether the ordinal number "h" of the input sample group including the i-th input sample is an odd number (S101). When the result of operation S101 is "YES", the i-th input sample may be buffered in the first memory of the buffer 142b (S102). Otherwise, when the result of operation S101 is “NO”, the i-th input sample may be buffered in the second memory of the buffer 142b (S103). The synchronization signal detector 142a may use the i-th input sample buffered in the first memory or the second memory to perform the PSS detection operation (S104).

The cell searcher 142 can determine whether "i" is "N-1" or whether "K" is "M" (S105). When the result of operation S105 is "No", "i" may be counted up (S106), and operations S100 to S105 may be performed again. As an example, the cell searcher 142 may detect the PSS group from the first input sample group by buffering the input samples included in the first input sample group in the first memory by using operations S100 to S106. When the result of operation S105 is "Yes", "h" may be counted up (S107), and operations S100 to S105 may be performed again. As an example, after completing the buffering operation of the first input sample group, the cell searcher 142 may perform the operation of buffering the second input sample group in the second memory.

When the result of operation S105 is "Yes", the synchronization signal detector 142a can use the PSS group detected from the specific input sample group through the operation S104 that has been performed multiple times to perform the SSS detection operation (S108) . In an example, the synchronization signal detector 142a can use the PSS group detected from the first input sample group in the interval in which the buffer operation of the second input sample group is performed to set the SSS configuration, and can use The set SSS configuration detects the SSS group from the first input sample group. The cell searcher 142 may use the PSS group and the SSS group detected from the specific input sample group to determine a valid cell (S109). As an example, the cell searcher 142 may use the PSS group and the SSS group detected from the first input sample group to determine a valid cell (S109). The cell searcher 142 can determine whether "h" is equal to "M/N" (or the total number of input sample groups) (S110). When the result of operation S110 is "No", operations S108 and S109 can be performed on other input sample groups. Otherwise, when the result of operation S110 is "Yes", the effective cell search operation performed using the input sample may be terminated.

FIG. 7 is a diagram for explaining a detailed operation method of the cell searcher 142 according to an exemplary embodiment of the inventive concept. In FIG. 7, it is assumed that the first memory MEM1 and the second memory MEM2 are used to perform an effective cell search operation based on a double buffering operation.

7, the cell searcher 142 may buffer the first input sample group 1 in the first memory MEM1 in the first interval 1 ^st ITV corresponding to the time between the time point “t1a” and the time point “t2a” ^st ISG same time, by input from the first sample group 1 ^st ISG implement a first detection operation PSS group 1 ^st PSS_D group to generate a first detection result PSS PSS_R1. As described above, the cell searcher 142 can generate the first PSS group detection result PSS_R1 in the following manner: calculate the difference between the input samples included in the first input sample group 1 ^st ISG and the corresponding PSS-based sequence Degree of association; and determining the input sample (or PSS) matching the condition that the association result is equal to or greater than the first reference value as the first PSS group.

The cell searcher 142 can buffer the second input sample group 2 ^nd ISG in the second memory MEM2 in the second interval 2 ^nd ITV corresponding to the time between the time point “t2a” and the time point “t3a”. , By performing the second PSS group detection operation 2 ^nd PSS_D from the second input sample group 2 ^nd ISG to generate the second PSS group detection result PSS_R2. In addition, the cell searcher 142 can be configured to perform the first SSS group detection operation based on the first PSS group detection result PSS_R1 in the specific interval F1 starting from the same or similar time point "t2a" 1 ^st SSS_D SSS configuration. The cell searcher 142 can perform the first SSS group detection operation 1 ^st SSS_D in the second interval 2 ^nd ITV based on the set SSS configuration, and generate the first SSS group detection result SSS_R1 until the time point "t3a ". As described above, the cell searcher 142 can generate the first SSS group detection result SSS_R1 in the following manner: calculate the difference between the input samples included in the first input sample group 1 ^st ISG and the corresponding SSS-based sequence Degree of association; and determining the input sample (or SSS) that matches the condition that the association result is equal to or greater than the second reference value as the first SSS group. Thereafter, the cell searcher 142 can use at least one of the first PSS group detection result PSS_R1 and the first SSS group detection result SSS_R1 during the time interval between the time point "t3a" and the time point "t4a". One to determine the effective cell.

In this way, the cell searcher 142 can perform the first effective cell search operation including the first PSS group detection operation 1 ^st PSS_D and the first SSS group detection operation 1 ^st SSS_D during the first search interval VCD_ITV . The first search interval VCD_ITV may include a first interval 1 ^st ITV and a second interval 2 ^nd ITV. Considering the time required to determine a valid cell, the cell searcher 142 may control the first SSS group detection operation 1 ^st SSS_D to be completed before the time point “t3a”. The cell searcher 142 may use at least one of the first PSS group detection result PSS_R1 and the first SSS group detection result SSS_R1 to determine a valid cell. The cell searcher 142 can perform a decoding operation on the physical broadcast channel PBCH of the determined effective cell, as described further with reference to FIG. 11 and FIG. 12.

The cell searcher 142 can buffer the third input sample group 3 ^rd ISG in the first memory MEM1 in the third interval 3 ^rd ITV corresponding to the time between the time point “t4a” and the time point “t5a”. , By performing the third PSS group detection operation 3 ^rd PSS_D from the third input sample group 3 ^rd ISG to generate the third PSS group detection result PSS_R3. In the third interval 3 ^rd ITV, the first input sample group 1 ^st ISG previously stored in the first memory MEM1 can be deleted. In addition, the cell searcher 142 can be configured to perform the second SSS group detection operation based on the second PSS group detection result PSS_R2 in the specific interval F2 starting from the same or similar time point "t4a" 2 ^nd SSS configuration of SSS_D. The cell searcher 142 can perform the second SSS group detection operation 2 ^nd SSS_D in the third interval 3 ^rd ITV based on the set SSS configuration, and generate the second SSS group detection result SSS_R2 until the time point "t5a ". Thereafter, the cell searcher 142 can use at least one of the second PSS group detection result PSS_R2 and the second SSS group detection result SSS_R2 during the time interval between the time point “t5a” and the time point “t6a” One to determine the effective cell.

In this way, the cell searcher 142 can perform an effective cell search operation for each input sample group, and perform an alternate buffer operation for each input sample group in the first memory MEM1 and the second memory MEM2.

FIG. 8 is a flowchart illustrating a method of searching for an effective cell of a cell searcher performed by a cell searcher according to an exemplary embodiment of the concept of the present invention. For example, the method shown in FIG. 8 can be implemented by the cell searcher 142. FIG. 8 shows the operation of the cell searcher performed in any one of the continuous first interval to the third interval in the buffer interval, and it should be understood that the operation of the cell searcher described in FIG. 8 can be applied to Other intervals in the buffer interval.

Referring to FIG. 8, the cell searcher may buffer the first input sample group for the first valid cell search operation in the first interval in the first memory (S200). The cell searcher may buffer the second input sample group for the second valid cell search operation in the second interval after the first interval in the second memory (S210). The cell searcher may buffer the third input sample group for the third effective cell search operation in the third interval after the second interval in the first memory (S220). The cell searcher may perform the first effective cell search operation in the first detection interval including the first interval and the second interval (S230). As described above, the first effective cell search operation may include the first PSS group detection operation using the first input sample group, the first SSS group detection operation, and the use of the first PSS group and the first SSS group Effective cell search operation. The cell searcher may perform a second effective cell search operation during the second detection interval including the second interval and the third interval (S240). As described above, the second effective cell search operation may include the second PSS group detection operation using the second input sample group, the second SSS group detection operation, and the use of the second PSS group and the second SSS group Effective cell search operation.

FIG. 9 is a flowchart showing operation S230 in FIG. 8 in detail.

Referring to FIG. 9, the cell searcher may detect the first PSS group from the first input sample group (S232). The cell searcher may generate the PSS-based sequence and calculate the degree of association between the input samples included in the first input sample group and the PSS-based sequence. The cell searcher may determine the input sample whose correlation degree is equal to or greater than the first reference value as the first PSS group based on the correlation degree calculation result.

The cell searcher can detect the first SSS group corresponding to the first PSS group from an input sample group (S234). The cell searcher can set the SSS configuration by obtaining specific information from the input samples included in the first PSS group, and can generate the SSS reference sequence based on the set SSS configuration. The cell searcher may calculate the degree of association between the input samples included in the first input sample group and the SSS-based sequence. The cell searcher may determine the input samples whose correlation degree is equal to or greater than the second reference value as the first SSS group based on the correlation degree calculation result. In an exemplary embodiment, the first reference value and the second reference value may be the same or different from each other.

The cell searcher may use at least one of the first PSS group and the first SSS group to determine an effective cell (S236). The cell searcher can input the first degree of association between X (where X is an integer equal to or greater than 1) input samples and the corresponding PSS-based sequence included in the first PSS group, and correspond to the X At least one of the second degree of association between the Y (where Y is an integer equal to or greater than 1) input sample and the corresponding SSS-based sequence included in the first SSS group of input samples generates a comparison value . The cell searcher may compare the generated comparison value with a third reference value, and may determine whether the cells corresponding to the X input samples and the Y input samples are valid cells based on the comparison result. For example, when the generated comparison value is equal to or greater than the third reference value, the cell searcher may determine that the cell is a valid cell. In an exemplary embodiment, the cell searcher may generate comparison values by applying the first weight to the first degree of relevance and applying the second weight to the second degree of relevance, respectively, and applying the two comparison values generated Add up. The first weight and the second weight may be values determined by multiple simulation results for accurate and effective cell search, and the first weight and the second weight may be preset in the cell searcher.

In this way, the cell searcher can use other input sample groups to perform effective cell search operations.

10A and 10B are respectively flowcharts of an operating method of a cell searcher (for example, the cell searcher 142) for stably performing an effective cell search operation according to an exemplary embodiment of the inventive concept. As an example, since the first input sample group 1 ^st ISG is deleted in the third interval 3 ^rd ITV in FIG. 7, the cell searcher may need to start before the third interval 3 ^rd ITV (ie, in the first search interval VCD_ITV) Use the first input sample group 1 ^st ISG to complete the first effective cell search operation. For example, the cell searcher may apply the method set forth below, so that the effective cell search operation can be completed within a specific search interval before the input sample group used for the effective cell search operation is deleted by multiple buffers.

Referring to FIG. 10A, when the cell searcher performs operation S232 (see FIG. 9), the cell searcher may determine candidate input samples that can be separated from the first input sample group into the first PSS group (S232a). The candidate input samples may have an association degree equal to or greater than the first reference value between corresponding PSS-based sequences. The number of input samples included in the first PSS group can be preset, or the number of input samples can be set in consideration of at least one of the performance of the terminal, the communication environment of the terminal, and the workload of the terminal. The cell searcher may determine the input samples included in the first PSS group from the candidate input samples to match the set number of input samples (S232b). For example, when it is determined that the first effective cell search operation can be performed correctly in the first search interval, the cell searcher can increase the number of input samples of the first PSS group, and when it is determined that the first search interval cannot be performed When the first effective cell search operation is performed correctly in the interval, the number of input samples of the first PSS group can be reduced. In addition, in an exemplary embodiment, when the operation S232b is performed, the cell searcher may determine the first PSS group from the candidate input samples in consideration of at least one of the magnitude of the correlation, the frequency interval between the candidate input samples, etc. group. Thereafter, the cell searcher may perform operation S234 (see FIG. 9).

Referring to FIG. 10B, when the cell searcher performs operation S234 (see FIG. 9), the cell searcher may select at least one input sample for detecting the first SSS group from the input samples of the first PSS group (S234a). For example, after taking into account at least one of the performance of the terminal, the communication environment of the terminal, the workload of the terminal, etc., the cell searcher may select the input sample from the first PSS group for the first SSS At least one input sample of group detection makes it possible to complete the first valid cell search operation within the first search interval even when the first PSS group has been determined. In an example, when it is determined that the first valid cell search operation can be performed in the first search interval, the cell searcher may increase the number of input samples of the first PSS group used for the first SSS group detection operation And when it is determined that the first effective cell search operation cannot be performed in the first search interval, the cell searcher can reduce the number of input samples of the first PSS group used for the first SSS group detection operation. The cell searcher may use the selected at least one input sample of the first PSS group to detect the first SSS group (S234b). Thereafter, the cell searcher may perform operation S236 (see FIG. 9).

11 and 12 are respectively a flowchart of a method of searching a cell of a terminal according to an exemplary embodiment of the concept of the present invention.

Referring to FIG. 11, the cell searcher may use all double-buffered input samples in a specific buffer interval to determine a valid cell (S300). For example, the cell searcher may use all input sample groups to perform multiple effective cell search operations, and as a result of performing the multiple effective cell search operations, the effective cell may be determined. The cell searcher may perform the remaining cell search operation based on the determined effective cell (S310). For example, the cell searcher can decode the physical broadcast channel PBCH received from the determined effective cell. When the decoding result of the physical broadcast channel PBCH is successful, it will report the decoding result to the effective cell and perform wireless communication with the effective cell. . However, when the decoding result of the physical broadcast channel PBCH fails, the cell searcher can decode the physical broadcast channel PBCH received from another valid cell.

Referring to FIG. 12, the cell searcher may use double-buffered input samples to perform an effective cell search operation on each input sample group to determine an effective cell (S300'). While performing a valid cell search operation, the cell searcher may determine whether a valid cell has been determined in L times (where L is an integer equal to or greater than 1) valid cell search operations (S310'). When the operation S310' is "No", the cell searcher can perform the operation S300', and when the operation S310' is "Yes", the buffering operation on the input samples that have not been buffered can be terminated (S320'). Alternatively, in FIG. 12, since the buffering operation is terminated when a valid cell is determined, the effective cell search operation for the input sample group can be omitted, and the input sample group will no longer be buffered thereafter. Therefore, the standard for determining a valid cell in operation S300' may be stricter than the standard in operation S300 in FIG. 11 to ensure a high probability of successful cell search. The cell searcher may perform the remaining cell search operations based on the determined effective cells determined in the L effective cell search operations (S330'). For example, the cell searcher can decode the physical broadcast channel PBCH received from the determined effective cell, and report the decoding result to the effective cell when the decoding result of the physical broadcast channel PBCH is successful, and perform wireless communication with the effective cell. However, when the decoding result of the physical broadcast channel PBCH fails, the cell searcher can re-receive the synchronization signal from the cell and perform the cell search operation again.

FIG. 13 is a block diagram of the synchronization signal detector 142a' according to an exemplary embodiment of the inventive concept.

Referring to FIG. 13, the synchronization signal detector 142a' may include a PSS detector 142a_1', an SSS detector 142a_2', and a timing controller 142a_3'. In the following, for the convenience of explanation, the configuration, components and technical aspects of the synchronization signal detector 142a shown in FIG. 5 that are the same as those of the SS detector 142a' shown in FIG. 13 will not be repeated. The timing controller 142a_3' may include an interval adjuster ITV_AD and a look-up table (LUT). The interval adjuster ITV_AD according to an exemplary embodiment may adjust the number of input samples included in the input sample group based on the adjustment information AD_I, and may adjust the length of the interval in which the input sample group is buffered in a specific memory. The adjustment information AD_I may include information related to the communication environment of the terminal, the performance of the terminal, and the workload of the terminal. The look-up table LUT may include information about adjustment information AD_I of various values, the number of input samples that match each of the various values included in the input sample group, and information about the length of the interval. The interval adjuster ITV_AD can refer to the lookup table LUT to obtain information related to the number of input samples and the length of the interval corresponding to the received adjustment information AD_I, and can adjust the number of input samples and the length of the interval based on the obtained information.

However, the timing controller 142a_3' shown in FIG. 13 is not limited to this. For example, in an exemplary embodiment, various adjustments may be made in consideration of various states of the terminal, the number of input samples of the input sample group, the length of the interval for buffering the input sample group, and so on.

14A to 14D are diagrams respectively showing the length of the input sample group buffer interval of a cell searcher (for example, the cell searcher 142) according to an exemplary embodiment of the inventive concept. 14A to 14D show exemplary embodiments of the intervals included in the buffer interval part BF_ITV _part of the same length.

Referring to FIG. 14A, the buffer interval part BF_ITV _part may include a first interval 1 ^st ITV to a fifth interval 5 ^th ITV. The first interval 1 ^st ITV to the fifth interval 5 ^th ITV may have the same length, and therefore, are included in each of the first input sample group 1 ^st ISG to the fifth input sample group 5 ^th ISG The number of input samples can be the same.

Referring to FIG. 14B, the buffer interval part BF_ITV _part may include a first interval 1 ^st ITV' to a third interval 3 ^rd ITV'. The first interval 1 ^st ITV' to the third interval 3 ^rd ITV' may have the same length, and the length of the first interval 1 ^st ITV' to the third interval 3 ^rd ITV' may be greater than the first interval 1 ^st in FIG. 14A. ITV to the length of the fifth interval 5 ^th ITV. However, the number of input samples included in each of the first input sample group 1 ^st ISG' to the third input sample group 3 ^rd ISG' may be the same, and include the first input sample group 1 ^st ISG The number of input samples in each of'to the third input sample group 3 ^rd ISG' may be greater than the first input sample group 1 ^st ISG to the fifth input sample group 5 ^th ISG included in FIG. 14A The number of input samples in each.

Referring to FIG. 14C, the buffer interval part BF_ITV _part may include a first interval 1 ^st ITV" to a fourth interval 4 ^th ITV". The first interval 1 ^st ITV" and the third interval 3 ^rd ITV" may have the same length, and therefore, the input samples included in each of the first interval 1 ^st ISG" and the third interval 3 ^rd ISG" The number can be the same. In addition, the second interval 2 ^nd ITV” and the fourth interval 4 ^th ITV” may have the same length, and therefore, each of the second interval 2 ^nd ITV” and the fourth interval 4 ^th ITV” The number of input samples in one can be the same. Alternatively, the lengths of the first interval 1 ^st ITV" and the third interval 3 ^rd ITV" may be different from the lengths of the second interval 2 ^nd ITV" and the fourth interval 4 ^th ITV". Therefore, the number of input samples of the first input sample group 1 ^st ISG” and the third input sample group 3 ^rd ISG” can be different from the second input sample group 2 ^nd ISG” and the fourth input sample group The number of input samples for group 4 ^th ISG. The length of the first interval 1 ^st ITV" and the third interval 3 ^rd ITV" may be less than the length of the second interval 2 ^nd ITV" and the fourth interval 4 ^th ITV", and the first input sample group 1 ^st ISG''And the number of input samples of the third input sample group 3 ^rd ISG” may be smaller than the number of input samples of the second input sample group 2 ^nd ISG” and the fourth input sample group 4 ^th ISG”.

Referring to FIG. 14D, the buffer interval part BF_ITV _part may include a first interval 1 ^st ITV"' to a fourth interval 4 ^th ITV"'. The lengths of the first interval 1 ^st ITV''' to the fourth interval 4 ^th ITV''' may be different from each other, and therefore, are included in the first input sample group 1 ^st ISG''' to the fourth input sample group 4 The number of input samples in each of ^th ISG"' may be different from each other.

As shown in FIGS. 14A to 14D, the length of the interval for buffering the input sample group can be implemented in various ways, and the capacity of the memory for multiple buffering can be implemented in various ways according to the length of the interval. In addition, as described above with reference to FIG. 13, the timing controller 142a_3' can dynamically adjust the length of the interval shown in FIGS. 14A to 14D, taking into account the communication environment of the terminal, the performance of the terminal, and the workload of the terminal. adjust. In this case, the maximum length of the interval (or the maximum number of input samples of the input sample group) can be taken into consideration to implement the buffer memory capacity.

FIG. 15 is a diagram illustrating a detailed operation method of a cell searcher (for example, the cell searcher 142) according to an exemplary embodiment of the inventive concept. In FIG. 15, it is assumed that the effective cell search operation is performed based on the triple buffering operation using the first memory MEM1 to the third memory MEM3.

15, the cell searcher may buffer the first input sample group 1 ^st in the first memory MEM1 in the first interval 1 ^st ITV corresponding to the time between the time point "t1b" and the time point "t2b" Simultaneously with the ISG, the first PSS group detection operation 1 ^st PSS_D is performed from the first input sample group 1 ^st ISG to generate the first PSS group detection result PSS_R1.

The cell searcher buffers the second input sample group 2 ^nd ISG in the second memory MEM2 in the second interval 2 ^nd ITV corresponding to the time from time "t2b" to time "t3b". The second PSS group detection operation 2 ^nd PSS_D can be performed from the input sample group 2 ^nd ISG to generate the second PSS group detection result PSS_R2. The cell searcher can buffer the third input sample group 3 ^rd ISG in the third memory MEM3 in the third interval 3 ^rd ITV corresponding to the time between the time point "t3b" and the time point "t5b", The third PSS group detection result PSS_R3 is generated by performing the third PSS group detection operation 3 ^rd PSS_D from the third input sample group 3 ^rd ISG.

The cell searcher can be configured to perform the first SSS group detection operation 1 ^st SSS_D based on the first PSS group detection result PSS_R1 in a specific interval F1 starting from the same or similar time point “t2b” SSS configuration. The cell searcher can perform the first SSS group detection operation 1 ^st SSS_D in the second interval 2 ^nd ITV and the third interval 3 ^rd ITV based on the set SSS configuration, and generate the first SSS group detection result SSS_R1 Until the time point "t4b". Thereafter, the cell searcher can use at least one of the first PSS group detection result PSS_R1 and the first SSS group detection result SSS_R1 during the time interval between the time point "t4b" and the time point "t5b". Determine the effective cell.

Thereafter, when the fourth input sample group is buffered in the first memory MEM1 in the fourth interval, the first input sample group 1 ^st ISG can be deleted from the first memory MEM1. In this way, the cell searcher can ensure the time for storing the first input sample group 1 ^st ISG in the first memory MEM1 by triple buffering instead of double buffering, and therefore, can extend The first search interval VCD_ITV' in which the first effective cell search operation (ie, the first PSS group detection operation 1 ^st PSS_D and the first SSS group detection operation 1 ^st SSS_D) is performed. The result of the first effective cell search operation can be applied to the search interval of other effective cell search operations, and therefore, the cell searcher can stably perform the effective cell search operation in the extended search interval. However, it should be understood that FIG. 15 only shows an exemplary embodiment, and according to the exemplary embodiment, multiple buffering of input samples can be implemented by using more memory.

FIG. 16 is a flowchart illustrating a method of searching for a cell of a terminal according to an exemplary embodiment of the concept of the present invention.

Referring to FIG. 16, the terminal can receive multiple synchronization signals (SS) from the cell (S400). The terminal may generate input samples by performing a sampling operation on the received synchronization signals based on a specific sample frequency (S410). The terminal may use the multiple memories to perform multiple buffering operations on the input samples (S420). For example, the multiple memories may alternately perform buffering operations on each of the assigned input sample groups. The terminal can perform an effective cell search operation for each input sample group (S430). As a result of performing at least one effective cell search operation, the terminal may determine the effective cell, and may decode the physical broadcast channel PBCH received from the determined effective cell (S440). The terminal can judge whether the decoding of the physical broadcast channel PBCH is successful (S450). When the result of operation S450 is "Yes", the terminal may report the cell search result to the valid cell (460). When the result of operation S450 is "No", the terminal can receive a new synchronization signal (S470). The terminal may perform cell search again based on the multiple buffering (S480), including performing an effective cell search operation for each input sample group.

FIG. 17 is a block diagram of an electronic device 1000 according to an exemplary embodiment of the inventive concept.

17, the electronic device 1000 can include a memory 1010, a processor unit 1020, an input/output controller 1040, a display unit 1050, an input device 1060, and a communication processing unit 1090. Here, there may be multiple memories 1010.

The memory 1010 may include a program storage unit 1011 and a data storage unit 1012. The program storage unit 1011 is used to store a program for controlling the operation of the electronic device 1000, and the data storage unit 1012 is used to store data generated during program execution. The data storage unit 1012 can store data used for the operation of the application program 1013 and the operation of the cell search program 1014 based on multiple buffering. The program storage unit 1011 may include an application program 1013 and a cell search program 1014 based on multiple buffering. Here, the program included in the program storage unit 1011 may be a set of instructions, and may be expressed as an instruction set.

The application program 1013 may include an application program that can be operated in the electronic device 1000. For example, the application program 1013 may include application instructions executed by the processor 1022. According to an exemplary embodiment of the concept of the present invention, the multi-buffer-based cell search program 1014 can divide input samples into input sample groups, alternately buffer the multiple memories, and perform effective cell search for each input sample group operating.

The peripheral device interface 1023 can control the connection of the input/output peripheral devices of the base station with the processor 1022 and the memory interface 1021. The processor 1022 can use at least one software program to control the base station to provide applicable services. At this time, the processor 1022 can execute at least one program stored in the memory 1010 to provide services corresponding to the applicable program.

The input/output controller 1040 can provide an interface between the input/output device (such as the display unit 1050 and the input device 1060) and the peripheral device interface 1023. The display unit 1050 can display, for example, status information, input characters, moving pictures, still pictures, and the like. For example, the display unit 1050 may display information related to the application program executed by the processor 1022.

The input device 1060 can provide input data generated by the selection of the electronic device 1000 to the processor unit 1020 via the input/output controller 1040. In this case, the input device 1060 may include a keypad, the keypad including at least one hardware button and a touchpad for sensing touch information. For example, the input device 1060 may provide touch information (such as touch, touch movement, and touch release that the touchpad has sensed) to the processor 1022 via the input/output controller 1040. The electronic device 1000 may include a communication processing unit 1090 that implements communication functions of voice communication and data communication.

As a tradition in the field to which the concept of the present invention belongs, functional blocks, units, and/or modules are used to illustrate and illustrate exemplary embodiments in the drawings. Those familiar with this technology should understand that these blocks, units and/or modules are physically implemented by electronic (or optical) circuits that can be formed by semiconductor-based manufacturing technology or other manufacturing technologies. ) Circuits are, for example, logic circuits, discrete components, microprocessors, hard-wired circuits, memory components, wiring connections, etc. In the case where the blocks, units and/or modules are implemented by a microprocessor or similar device, the blocks, units and/or modules can be programmed with software (for example, microcode) to Perform various functions discussed in this article, and can be driven by firmware and/or software as needed. Alternatively, each block, unit, and/or module can be implemented by dedicated hardware, or by dedicated hardware that performs some functions and a processor that performs other functions (for example, one or more programmed micro Processor and associated circuits).

Although the concept of the invention has been specifically shown and explained with reference to the exemplary embodiments of the concept of the invention, it should be understood that without departing from the spirit and scope of the concept of the invention defined by the scope of the appended patent Make various changes in form and details.

1: wireless communication system 10: first cell/cell 20: second cell/cell 30: third cell/cell 100: terminal 110: antenna 120: front-end circuit 130: transceiver 131: receiver 132: transmitter 133 : Switch 140: Controller 142: Cell searcher 142a, 142a': Synchronization signal (SS) detector 142a_1, 142a_1': PSS detector 142a_2, 142a_2': SSS detector 142a_3, 142a_3': Timing controller 142b: Buffer 1000: electronic device 1010, MEM: memory 1011: program storage unit 1012: data storage unit 1013: application program 1014: cell search program based on multiple buffers 1020: processor unit 1021: memory interface 1022: processing 1023: peripheral device interface 1040: input/output controller 1050: display unit 1060: input device 1090: communication processing unit 1 ^st ISG, 1 ^st ISG', 1 ^st ISG'', 1 ^st ISG''': first Input sample group 1 ^st ITV, 1 ^st ITV', 1 ^st ITV'', 1 ^st ITV''': first interval 1 ^st PSS_D: first PSS group detection operation 1 ^st SSS_D: first SSS group Detection operation 2 ^nd ISG, 2 ^nd ISG', 2 ^nd ISG'', 2 ^nd ISG''': second input sample group 2 ^nd ITV, 2 ^nd ITV', 2 ^nd ITV'', 2 ^nd ITV''': second interval 2 ^nd PSS_D: second PSS group detection operation 2 ^nd SSS_D: second SSS group detection operation 3 ^rd ISG, 3 ^rd ISG', 3 ^rd ISG'', 3 ^rd ISG''': third input sample group 3 ^rd ITV, 3 ^rd ITV', 3 ^rd ITV", 3 ^rd ITV''': third interval 3 ^rd PSS_D: third PSS group detection operation 4 ^th ISG, 4 ^th ISG'', 4 ^th ISG''': the fourth input sample group 4 ^th ITV, 4 ^th ITV'', 4 ^th ITV''': the fourth interval 5 ^th ISG: the fifth input sample group 5 ^th ITV : Fifth interval n ^th ISG: n ^th input sample group n ^th ITV: n ^th interval AD_I: adjustment information BF_ITV: buffer interval BF_ITV _part : buffer interval parts F1, F2: specific interval ITV_AD: interval adjuster LUT: lookup table MEM1: First memory MEM2: Second memory MEM3: Third memory PBCH: Physical broadcast channel PSS: Main synchronization signal PSS _R1: first PSS group detection result PSS_R2: second PSS group detection result PSS_R3: third PSS group detection result RB: resource blocks S100, S101, S102, S103, S104, S105, S106, S107 , S108, S109, S110, S200, S210, S220, S230, S240, S232, S234, S236, S232a, S232b, S234a, S234b, S300, S310, S300', S310', S320', S330', S400, S410 , S420, S430, S440, S450, S460, S470, S480: Operation SSB1: First Sync Signal Block (SSB) SSB2: Second SSB SSB3: Third SSB SSB4: Fourth SSB SSB5: Fifth SSB SSB6: No. Sixth SSB SSB7: seventh SSB SSB8: eighth SSB SSS: auxiliary synchronization signal SSS_R1: first SSS group detection result SSS_R2: second SSS group detection result t1a, t2a, t3a, t4a, t5a, t6a, t1b , T2b, t3b, t4b, t5b: time points TM_C1, TM_C1': first timing control signal TM_C2, TM_C2': second timing control signal T _SSB : SSB burst collection period TX_B1: first transmission beam TX_B2: second transmission Beam TX_B3: third transmit beam TX_B4: fourth transmit beam TX_B5: fifth transmit beam TX_B6: sixth transmit beam TX_B7: seventh transmit beam TX_B8: eighth transmit beam VCD_ITV, VCD_ITV': first search interval

The above and other features of the inventive concept will become more apparent by describing in detail the exemplary embodiments of the inventive concept with reference to the accompanying drawings. In the accompanying drawings: FIG. 1 is a block diagram of a wireless communication system according to an exemplary embodiment of the inventive concept. FIG. 2 is a diagram showing a synchronization signal including a synchronization signal block (SSB) used during cell search. Fig. 3 is a block diagram of a terminal according to an exemplary embodiment of the concept of the present invention. FIG. 4 is a diagram for explaining a multiple buffering operation according to an exemplary embodiment of the inventive concept. FIG. 5 is a block diagram of a synchronization signal detector according to an exemplary embodiment of the inventive concept. 6 is a flowchart illustrating an operating method of a cell searcher according to an exemplary embodiment of the concept of the present invention. FIG. 7 is a diagram for explaining a detailed operation method of a cell searcher according to an exemplary embodiment of the inventive concept. FIG. 8 is a flowchart illustrating a method of searching for a valid cell performed by a cell searcher according to an exemplary embodiment of the concept of the present invention. FIG. 9 is a flowchart showing operation S230 in FIG. 8 in detail. 10A and 10B are respectively flowcharts of an operating method of a cell searcher for stably performing an effective cell search operation according to an exemplary embodiment of the inventive concept. FIG. 11 and FIG. 12 are respectively a flowchart of a method of searching for a cell performed by a terminal according to an exemplary embodiment of the concept of the present invention. FIG. 13 is a block diagram of a synchronization signal detector according to an exemplary embodiment of the inventive concept. 14A to 14D are diagrams respectively showing the length of an interval for buffering an input sample group of a cell searcher according to an exemplary embodiment of the inventive concept. FIG. 15 is a diagram for explaining a detailed operation method of a cell searcher according to an exemplary embodiment of the inventive concept. FIG. 16 is a flowchart illustrating a method of searching for a cell of a terminal according to an exemplary embodiment of the concept of the present invention. FIG. 17 is a block diagram of an electronic device according to an exemplary embodiment of the inventive concept.

S100, S101, S102, S103, S104, S105, S106, S107, S108, S100, S110: Operation

Claims (25)

An operating method of a terminal, the terminal being configured to perform a cell search by buffering input samples using a first memory and a second memory, the operating method includes: While buffering the first input sample group in the first memory in the first interval, detecting the first main synchronization signal group from the first input sample group; While buffering a second input sample group in the second memory in a second interval after the first interval, detecting a second main synchronization signal group from the second input sample group, and Detecting a first auxiliary synchronization signal group corresponding to the first main synchronization signal group from the first input sample group; and While buffering a third input sample group in the first memory in a third interval after the second interval, detecting a third main synchronization signal group from the third input sample group, and A second auxiliary synchronization signal group corresponding to the second main synchronization signal group is detected from the second input sample group. The operation method as described in item 1 of the scope of patent application, wherein The number of input samples of the first main synchronization signal group is preset to complete the detection of the first auxiliary synchronization signal group in the second interval, or used to detect the first auxiliary synchronization signal The number of input samples of the first main synchronization signal group of the signal group is limited. The operation method described in item 1 of the scope of patent application further includes: The first input sample group stored in the first memory is detected in the third interval. According to the operation method described in claim 1, wherein detecting the first main synchronization signal group further includes: Calculating the degree of correlation between the input samples of the first input sample group and the sequence based on the master synchronization signal; and Based on the degree of association, the first primary synchronization signal group is determined from the first input sample group. According to the operation method described in claim 1, wherein detecting the first auxiliary synchronization signal group further includes: Selecting any one of the input samples included in the first main synchronization signal group; Set the auxiliary synchronization signal configuration based on the information obtained from the selected input sample; and The auxiliary synchronization signal corresponding to the selected input sample is detected based on the set auxiliary synchronization signal configuration. As for the operation method described in item 5 of the scope of patent application, wherein detecting the auxiliary synchronization signal further includes: Generating a sequence based on the auxiliary synchronization signal based on the set auxiliary synchronization signal configuration; Calculating the degree of correlation between the sequence based on the auxiliary synchronization signal and the input samples of the first input sample group; and The auxiliary synchronization signal is detected based on the degree of association. The operation method described in item 5 of the scope of patent application, wherein the information obtained from the selected input sample includes: The primary identifier of the cell in which the selected input sample has been transferred to the terminal, and the timing information of the cell corresponding to the selected input sample. The operation method as described in item 1 of the scope of patent application, wherein The first auxiliary synchronization signal group is detected from the first input sample group stored in the first memory. The operation method as described in item 1 of the scope of patent application, wherein The length of the first interval to the length of the third interval varies according to at least one of the communication environment of the terminal, the performance of the terminal, and the workload of the terminal. The operation method described in item 1 of the scope of patent application further includes: In the buffer interval of the terminal machine that includes the first interval to the third interval, determine among a plurality of cells corresponding to the first primary synchronization signal group and the first auxiliary synchronization signal group Effective cell. The operating method described in item 10 of the scope of patent application, wherein determining the effective cell includes: The first degree of association between the X input samples included in the first main synchronization signal group and the corresponding sequence based on the main synchronization signal, and the first correlation between the X input samples included in the first auxiliary synchronization signal group and corresponding Generating a comparison value from at least one of the second degree of association between the Y input samples of the X input samples and the corresponding sequence based on the auxiliary synchronization signal; Where X is an integer equal to or greater than 1, and Y is an integer equal to or greater than 1; Comparing the comparison value with a reference value; and Based on the comparison result, it is determined whether the cells corresponding to the X input samples and the Y input samples are the effective cells. The operation method described in item 11 of the scope of patent application, wherein generating the comparison value includes: The comparison value is generated by adding the first degree of association to which the first weight is applied to the second degree of association to which the second weight is applied. The operation method described in item 10 of the scope of patent application further includes: When at least one of the multiple cells is determined to be the valid cell, terminating the buffering operation on the input samples; and Perform a decoding operation on the physical broadcast channel received from the effective cell. The operation method described in item 13 of the scope of patent application includes: When the decoding operation on the physical broadcast channel is successful, report the cell search result to the effective cell and terminate the cell search. An operating method for a cell terminal, the cell terminal being equipped with multiple memories to alternately buffer input samples generated for cell search operations in a specific buffer interval, the operating method comprising: Buffering the first input sample group for performing the first effective cell search operation in the first interval in the first memory; and Buffering a second input sample group for performing a second effective cell search operation in a second interval after the first interval in the second memory, The first effective cell search operation is performed using the first input sample group in a first search interval including the first interval and the second interval. The operation method according to item 15 of the scope of patent application, wherein the first effective cell search operation includes: Detecting a first main synchronization signal group from the first input sample group; Detecting a first auxiliary synchronization signal group corresponding to the first main synchronization signal group from the first input sample group; and The first primary synchronization signal group and the first auxiliary synchronization signal group are used to determine an effective cell. The operation method described in item 16 of the scope of patent application, wherein determining the effective cell further includes: Based on the first degree of association between the X input samples included in the first primary synchronization signal group and the corresponding sequence based on the primary synchronization signal, and included in the first auxiliary synchronization signal group and corresponding Determine whether the cells corresponding to the X input samples and the Y input samples are valid based on the second degree of association between the Y input samples of the X input samples and the corresponding sequence based on the auxiliary synchronization signal Community, Where X is an integer equal to or greater than 1, and Y is an integer equal to or greater than 1. The operation method described in item 16 of the scope of patent application includes: When the effective cell is determined in the first effective cell search operation, the buffering operation on the multiple memories is terminated. The operation method described in item 18 of the scope of patent application, wherein the first effective cell search operation further includes: Perform a decoding operation on the physical broadcast channel received from the determined effective cell; and Perform the first effective cell search operation again or terminate the first effective cell search operation based on the decoding result of the physical broadcast channel. The operation method described in item 15 of the scope of patent application includes: Buffering a third input sample group for performing a third effective cell search operation in the first memory in a third interval after the second interval, The first input sample group is deleted in the third interval. The operation method described in item 15 of the scope of patent application includes: Buffering a third input sample group for performing a third effective cell search operation in a third interval after the second interval in the third memory, The first search interval further includes the third interval. The operation method described in item 21 of the scope of patent application includes: Buffering a fourth input sample group for performing a fourth effective cell search operation in the fourth interval after the third interval in the first memory, The first input sample group is deleted in the fourth interval. The operation method as described in item 15 of the scope of patent application, wherein The length of the first interval and the length of the second interval vary according to at least one of the communication environment of the terminal, the performance of the terminal, and the workload of the terminal. A terminal machine, including: The buffer is divided into a first memory and a second memory to alternately buffer the input samples generated for the cell search operation in a specific buffer interval; and The baseband processor is configured to control the first effective cell search operation performed by the first input sample group that is to be buffered in the first memory in the first interval during the first search interval, the The first search interval includes the first interval and a second interval after the first interval, The second input sample group used to perform the second effective cell search operation in the second interval is buffered in the second memory. Such as the terminal described in item 24 of the scope of patent application, where The baseband processor is configured to determine when a primary synchronization signal matching a specific reference and a corresponding auxiliary synchronization signal are detected from the first input sample group through the first effective cell search operation The cells corresponding to the primary synchronization signal and the secondary synchronization signal are valid cells and the buffering of the buffer is terminated.

Images