WO2022196969A1

WO2022196969A1 - Method for accessing network cell, method and apparatus for accessing mobile terminal

Info

Publication number: WO2022196969A1
Application number: PCT/KR2022/002788
Authority: WO
Inventors: Huajing Li
Original assignee: Samsung Electronics Co., Ltd.
Priority date: 2021-03-19
Filing date: 2022-02-25
Publication date: 2022-09-22
Also published as: CN115119285A

Abstract

A method for accessing a network cell, a method for accessing a mobile terminal and apparatuses thereof are disclosed. A method for accessing a network cell by a mobile terminal includes: scanning a specific unlicensed frequency band, in response to the mobile terminal requesting to access the network cell; decoding, in response to obtaining a predetermined signal by scanning, the predetermined signal; searching for a cell synchronization signal, based on a decoding result; and completing downlink synchronization and accessing the network cell, based on the searched cell synchronization signal.

Description

METHOD FOR ACCESSING NETWORK CELL, METHOD AND APPARATUS FOR ACCESSING MOBILE TERMINAL

The present disclosure relates to the field of mobile communication, in particular to a method for accessing a network cell by a mobile terminal, a method for accessing a mobile terminal by a base station, an apparatus for accessing a network cell by a mobile terminal, and an apparatus for accessing a mobile terminal by a base station.

When a mobile terminal accesses a wireless network for the first time or lose the wireless network for a long time, it needs to scan supported frequency bands to acquire wireless network frequency channels available in the current region to access the wireless network. For example, in the following scenarios: 1) The mobile terminal accesses the wireless network for the first time; 2) After a user just gets off the plane and turns off the flight mode, the mobile terminal needs to search for local network cells since it is far away from the place of departure; 3) On a high-speed rail, due to a fast speed of the high-speed rail and an incomplete network coverage along the way, the mobile terminal is prone to lose the network and needs to reconnect to the wireless network; and 4) When an underground parking lot spans a long distance from an entrance to an exit, and an underground signal is weak and it is easy for the mobile terminal to lose the network, after returning to the ground, the mobile terminal needs to reconnect to the wireless network.

Currently, the mobile terminal supports two network search modes: system scan and full band scan. The system scan may search the network based on frequency channels of the network cell where the mobile terminal has previously resided. If there is no corresponding historical frequency channel record or the system scan cannot find any available frequency channel, full band scan is performed. The scan is performed based on a list of all frequency bands supported by the mobile terminal to acquire available frequency channels. With the commercialization and development of 5G NR (5G New Radio) technology and the improvement of LTE technology, the mobile terminal supports more and more communication frequency bands, and time required to scan is getting longer and longer. The conventional network search process will inevitably lead to too long time for searching the network, and it is difficult for the mobile terminal to quickly access the network, affecting user network experience.

To optimize the efficiency of current network search process and improve network search speed, the present disclosure proposes the following solution: in the case of avoiding interference to other wireless frequency bands, a base station side uses a specific unlicensed frequency band (for example, about 2.4Ghz, about 5Ghz and/or about 6Ghz frequency band used by WIFI), broadcasts frequency channel information of a currently covered wireless cell at a certain time interval on a specific channel. A mobile terminal may preferentially search for the specific unlicensed frequency band, decode the frequency channel information carried on the frequency band, and directly search for a synchronization signal of the corresponding network cell based on the frequency channel information to complete downlink synchronization and network access.

According to an aspect of the present disclosure, a method for accessing a network cell by a mobile terminal is provided, the method including: scanning a specific unlicensed frequency band, in response to the mobile terminal requesting to access the network cell; decoding, in response to obtaining a predetermined signal by scanning, the predetermined signal; searching for a cell synchronization signal, based on a decoding result; and completing downlink synchronization and accessing the network cell, based on the searched cell synchronization signal.

Optionally, the scanning a specific unlicensed frequency band includes: measuring a signal strength of a signal obtained by scanning the specific unlicensed frequency band; and determining the obtained signal as the predetermined signal, in response to the measured signal strength being greater than a predetermined threshold.

Optionally, a scanning duration for scanning the specific unlicensed frequency band is a sum of a transmission time slot and a dormant time slot of the predetermined signal, which are set in advance.

Optionally, a duration of the transmission time slot is 10ms, a duration of the dormant time slot is dynamically adjustable, and/or a duration of the dormant time slot is 80ms-300ms.

Optionally, the decoding the predetermined signal includes: decoding the predetermined signal with a specific decoding scheme, and extracting frequency channel information for accessing the network cell from the decoded predetermined signal.

Optionally, the decoding the predetermined signal includes: performing QPSK demodulation on the predetermined signal to obtain a corresponding bit stream; positioning the bit stream to obtain a frame delimiter of the bit stream; and extracting the frequency channel information for accessing the network cell from the bit stream, in response to the frame delimiter of the bit stream being the same as a preset symbol.

Optionally, the searching for a cell synchronization signal, based on a decoding result includes: searching for the cell synchronization signal to acquire a physical cell identity of a cell, based on the extracted frequency channel information for accessing the network cell.

Optionally, the completing downlink synchronization and accessing the network cell, based on the searched cell synchronization signal includes: completing downlink synchronization between the mobile terminal and a base station, based on the acquired physical cell identity; and initiating a random access procedure to access the network cell, after completing the downlink synchronization.

Optionally, the method further includes: performing a system scan and/or a full band scan to access the network cell, in response to failing to obtain the predetermined signal by scanning and/or failing to find the cell synchronization signal.

Optionally, the method further includes: performing a system scan and/or a full band scan to access the network cell, in response to the frame delimiter of the bit stream being different from the preset symbol.

Optionally, the specific unlicensed frequency band is about 2.4GHz, about 5Ghz and/or about 6Ghz frequency band.

According to another aspect of the present disclosure, a method for accessing a mobile terminal by a base station is provided, the method including: broadcasting periodically a predetermined signal including frequency channel information for accessing a network cell covered by the base station on a specific unlicensed frequency band; and interacting with the mobile terminal to complete the mobile terminal accessing to the network cell covered by the base station, in response to the mobile terminal initiating a random access procedure for the network cell covered by the base station based on the predetermined signal.

Optionally, the predetermined signal is acquired by encoding a bit stream including the frequency channel information for accessing the network cell.

Optionally, the predetermined signal is acquired by QPSK encoding the bit stream including the frequency channel information for accessing the network cell.

Optionally, the bit stream includes a frame delimiter, information indicating the number of frequency channels of the network cell covered by the base station, k+1 CRC check information, and frequency channel information of k frequency channels, where k is the number of frequency channels of the network cell covered by the base station.

Optionally, a period of the predetermined signal including the frequency channel information for accessing the network cell broadcasting on the specific unlicensed frequency band is composed of a transmission time slot for transmitting the predetermined signal and a dormant time slot.

According to another aspect of the present disclosure, an apparatus for accessing a network cell of a mobile terminal is provided, the apparatus including: a scanning unit, configured to scan a specific unlicensed frequency band, in response to the mobile terminal requesting to access the network cell; a decoding unit, configure to decode, in response to obtaining a predetermined signal by scanning, the predetermined signal; a searching unit, configure to search for a cell synchronization signal, based on a decoding result; and a synchronization and accessing unit, configured to complete downlink synchronization and access the network cell, based on the searched cell synchronization signal.

According to another aspect of the present disclosure, an apparatus for accessing a mobile terminal of a base station is provided, the apparatus including: a broadcasting unit, configured to broadcast periodically a predetermined signal comprising frequency channel information for accessing a network cell covered by the base station on a specific unlicensed frequency band; and an accessing unit, configured to interact with the mobile terminal to complete the mobile terminal accessing to the network cell covered by the base station, in response to the mobile terminal initiating a random access procedure for the network cell covered by the base station based on the predetermined signal.

According to another aspect of the present disclosure, a computer readable storage medium storing computer programs is provided, the computer programs, when executed by a processor, implement the method for accessing a network cell by a mobile terminal or the method for accessing a mobile terminal by a base station.

According to another aspect of the present disclosure, a computing apparatus is provided, the computing apparatus including: a processor; and a memory, storing a computer program, the computer program, when executed by the processor, implement the method for accessing a network cell by a mobile terminal or the method for accessing a mobile terminal by a base station.

Compared with the existing network search method, the method for accessing a network cell by a mobile terminal, the method for accessing a mobile terminal by a base station, the apparatus for accessing a network cell of a mobile terminal, and the apparatus for accessing a mobile terminal of a base station according to the present disclosure, may greatly save network search time, improve network search speed, and optimize the efficiency of network recovery after network loss. In addition, an unlicensed frequency band is used to indicate information of a wireless commercial frequency band, because the unlicensed frequency band does not involve commercial and legal risks, having small bandwidth and limited frequency band range, and the scanning and decoding time will not be too long. After acquiring frequency channel information of an effective network cell, the conventional network search process may be skipped, downlink synchronization with the cell may be directly completed, and the wireless network access is completed very quickly.

The above and other objectives and features of embodiments of the present disclosure will become clearer from the following description in conjunction with the accompanying drawings exemplarily showing the embodiments, in which:

Fig. 1 is a flowchart illustrating a method for accessing a network cell by a mobile terminal according to an embodiment of the present disclosure;

Fig. 2 is a flowchart illustrating a method for accessing a mobile terminal by a base station according to an embodiment of the present disclosure;

Fig. 3 is a diagram showing an example of a bit stream including frequency channel information for accessing a network cell according to an embodiment of the present disclosure;

Fig. 4 is a block diagram showing an apparatus for accessing a network cell of a mobile terminal according to an embodiment of the present disclosure;

Fig. 5 is a block diagram showing an apparatus for accessing a mobile terminal of a base station according to an embodiment of the present disclosure; and

Fig. 6 is a block diagram showing a computing apparatus according to an embodiment of the present disclosure.

The following specific implementations are provided to help readers gain a comprehensive understanding of the methods, devices, and/or systems described herein. However, after understanding the disclosure of the present application, various changes, modifications and equivalents of the methods, devices and/or systems described herein will be clear. For example, the orders of operations described herein are only examples, and are not limited to those set forth herein, but except for operations that must occur in a specific order, they may be changed as will be clear after understanding the disclosure of the present application. In addition, for more clarity and conciseness, descriptions of features known in the art may be omitted.

The features described herein may be implemented in different forms and should not be construed as being limited to the examples described herein. On the contrary, the examples described herein have been provided to show only some of the many feasible methods for implementing the methods, devices, and/or systems described herein, which will be clear after understanding the disclosure of the present application.

As used herein, the term "and/or" includes any one of the associated listed items and any combination of any two or more.

Although terms such as "first", "second" and "third" may be used herein to describe various members, components, regions, layers or parts, these members, components, regions, layers or parts should not be restricted by these terms. On the contrary, these terms are only used to distinguish one member, component, region, layer or part from another member, component, region, layer or part. Therefore, without departing from the teaching of the examples, a first member, a first component, a first region, a first layer, or a first part in the examples described herein may also be referred to as a second member, a second component, a second region, a second layer or a second part.

In the specification, when an element (such as a layer, region, or substrate) is described as being "on", "connected to", or "coupled to" another element, the element may be directly "on" the other element, directly "connected to" or "coupled to" another element, or there may be one or more other elements intervening therebetween. In contrast, when an element is described as being "directly on", "directly connected to" or "directly coupled to" another element, there may be no intervening elements.

The terms used herein are only used to describe various examples, and are not intended to limit the present disclosure. Unless the context clearly indicates otherwise, the singular form is intended to include the plural form. The terms "including", "comprising" and "having" indicate the existence of the features, numbers, operations, members, elements, and/or combinations thereof, but do not exclude the existence or addition of one or more other features, numbers, operations, members, elements and/or combinations thereof.

Unless defined otherwise, all terms used herein (including technical terms and scientific terms) have the same meaning as commonly understood by those skilled in the art to which the present disclosure belongs after understanding the present disclosure. Unless clearly defined as such herein, terms such as those defined in the general dictionaries should be interpreted as having a meaning consistent with their contextual meaning in the related field and in the present disclosure, and should not be interpreted as having ideal or excessive formal meaning.

In addition, in the description of the examples, when it is considered that a detailed description of a well-known related structure or function will cause a vague interpretation of the present disclosure, such detailed description will be omitted.

In the conventional solution for a mobile terminal to access the wireless network, a base station periodically sends synchronization signals on a specific downlink broadcast channel of a current network cell. When the mobile terminal accesses the wireless network, it scans based on historical frequency channels of the network cell where it previously resided, or scans a list of all supported frequency bands, sorts based on the amount of energy received on the scanned frequency bands, lists all possible frequency channels, then retrieves a synchronization signal on each frequency channel, and finally completes downlink synchronization and network access based on the retrieved synchronization signal. In this case, when performing full band scan, the average time cost is generally as long as half a minute or more.

In the solution for a mobile terminal to access the wireless network of the present disclosure, a base station may send cell frequency channel information carrying a current region at a certain time interval using a specific unlicensed frequency band (such as but not limited to about 2.4GHz, about 5Ghz and/or about 6Ghz). When the mobile terminal accesses the wireless network, it first scans the specific unlicensed frequency band. If a corresponding signal is detected, the mobile terminal tries to decode and judge whether the signal is frequency channel information for assisting to access a network cell. If the decoding is successful, the mobile terminal acquires the frequency channel information of the network cell, uses the frequency channel information to directly retrieve a synchronization signal on the corresponding frequency channel, to complete downlink synchronization and network access.

Hereinafter, the present disclosure will be described in more detail with reference to the accompanying drawings.

Fig. 1 is a flowchart illustrating a method for accessing a network cell by a mobile terminal according to an embodiment of the present disclosure.

Referring to Fig. 1, in operation S101, scanning a specific unlicensed frequency band (such as but not limited to about 2.4GHz, about 5Ghz and/or about 6Ghz), in response to the mobile terminal requesting to access the network cell. For example, when the mobile terminal accesses a wireless network for the first time, or re-accesses the wireless network after disconnecting from the wireless network, the mobile terminal may request to access a network cell, thereby performing operation S101. Alternatively, operation S101 may be performed before a system scan and/or a full band scan.

In particular, the scanning a specific unlicensed frequency band may include: measuring a signal strength of a signal obtained by scanning the specific unlicensed frequency band; and determining the obtained signal as the predetermined signal, in response to the measured signal strength being greater than a predetermined threshold. Here, the predetermined threshold may be determined by those skilled in the art based on energy (signal strength) of a frequency channel for accessing the network cell. Alternatively, a scanning duration for scanning the specific unlicensed frequency band may be a sum of a transmission time slot and a dormant time slot of the predetermined signal, which are set in advance. A duration of the transmission time slot may be, for example, 10ms, a duration of the dormant time slot is dynamically adjustable. Generally speaking, a duration of the dormant time slot may be, for example, 80ms-300ms.

In operation S102, determining whether to obtain the predetermined signal by scanning, and in response to obtaining a predetermined signal by scanning, in operation S103, decoding the predetermined signal obtained by scanning. According to an embodiment of the present disclosure, the predetermined signal obtained by scanning may be decoded in a specific decoding scheme, and frequency channel information for accessing the network cell may be extracted from the decoded predetermined signal. More specifically, in operation S103, the predetermined signal obtained by scanning may be first subjected to QPSK (Quadrature Phase Shift Keying) demodulation (However, the present disclosure is not limited herein) to obtain a corresponding bit stream, and then the obtained bit stream is positioned to obtain a frame delimiter of the bit stream. When the frame delimiter of the bit stream is the same as a preset symbol, the frequency channel information for accessing the network cell may be extracted from the bit stream. However, when the frame delimiter of the bit stream is different from the preset symbol, the conventional system scan and/or full band scan may be performed to access the network cell.

In operation S104, searching for a cell synchronization signal, based on a decoding result. Specifically, in operation S104, based on the extracted frequency channel information for accessing the network cell, the cell synchronization signal may be searched for to acquire a physical cell identity (PCI) of the cell.

In operation S105, determining whether the cell synchronization signal is searched. In operation S106, completing downlink synchronization and accessing the network cell, based on the searched cell synchronization signal. For example, downlink synchronization between the mobile terminal and a base station may be completed based on an acquired physical cell identity. Thereafter, after completing the downlink synchronization, a random access procedure is initiated to access the network cell.

Alternatively, if it is determined in operation S102 that the predetermined signal cannot be obtained by scanning, and/or it is determined that the cell synchronization signal cannot be searched in operation S105, the conventional system scan and/or full band scan may be performed to access the network cell.

The method for accessing a network cell by a mobile terminal according to an embodiment of the present disclosure, by sending the frequency channel information for accessing the network cell on the unlicensed frequency band, may reduce time for accessing the network cell, improve speed for accessing the network cell, and improve user experience on the mobile terminal in operation S107.

Fig. 2 is a flowchart illustrating a method for accessing a mobile terminal by a base station according to an embodiment of the present disclosure.

In operation S201, broadcasting periodically a predetermined signal including frequency channel information for accessing a network cell covered by the base station on a specific unlicensed frequency band. As mentioned above, the specific unlicensed frequency band may be 2.4GHz frequency band used by WIFI. However, the present disclosure is not limited herein. For example, the specific unlicensed frequency band may also be 5GHz frequency band, 6GHz frequency band, and so on. In order to broadcast on the specific unlicensed frequency band, the base station may be equipped with a wireless transmitting module dedicated to the unlicensed frequency band. On the other hand, a transceiver of the existing base station generally supports a wide range of frequency bands. If the base station supports this unlicensed frequency band, there is no need to add new wireless transmission hardware. Instead, the base station's own transceiver may be used to broadcast on the unlicensed frequency band.

According to an embodiment of the present disclosure, the predetermined signal may be acquired by encoding the bit stream including the frequency channel information for accessing the network cell. More specifically, the predetermined signal may be acquired by QPSK encoding the bit stream including the frequency channel information for accessing the network cell. Here, the bit stream may include a frame delimiter, information indicating the number of frequency channels of the network cell covered by the base station, k+1 CRC check (cyclic redundancy check) information and frequency channel information of k frequency channels, where k is the number of frequency channels of the network cell covered by the base station.

Fig. 3 is a diagram showing an example of a bit stream including frequency channel information for accessing a network cell according to an embodiment of the present disclosure.

Referring to Fig. 3, a bit stream including frequency channel information for access a network cell may be composed of n 32-bit bits, and n is equal to the number of frequency channels (for example, k) of the network cell covered by a base station plus 1. In the first 32-bit bits, the first 16 bits (D31: D16) define a frame delimiter. The frame delimiter indicates the start of the bit stream, and may be used by the mobile terminal to verify whether the bit stream is the bit stream including the frequency channel information for accessing the network cell. The last 16 bits includes information about the number of frequency channels of the network cell covered by the base station (D15: D8) and CRC check information (D7: D0). After the first 32-bit bits, k 32-bit bits are appended. In each of the k 32-bit bits, the first 24 bits (D31: D8) include frequency channel information of the corresponding frequency channels, and the last 8 bits (D7: D0) are the CRC check information.

Referring back to Fig. 2, in operation S201, in order to save energy consumption in the base station, the predetermined signal is periodically broadcast on the specific unlicensed frequency band at a certain time interval. However, the time interval cannot be too long, so as not to affect the efficiency of network search, nor too short, so as not to increase energy consumption. According to an embodiment of the present disclosure, the time interval (that is, a period of the predetermined signal including the frequency channel information for accessing the network cell broadcasting on the specific unlicensed frequency band) may be composed of a transmission time slot for transmitting the predetermined signal and a dormant time slot. A duration of the transmission time slot may be, for example, 10ms, and a duration of the dormant time slot is dynamically adjustable. Generally speaking, the duration of the dormant time slot may be, for example, 80ms-300ms.

Then, in operation S202, interacting with the mobile terminal to complete the mobile terminal accessing to the network cell covered by the base station, in response to the mobile terminal initiating a random access procedure for the network cell covered by the base station based on the predetermined signal broadcast in operation S201.

Fig. 4 is a block diagram showing an apparatus for accessing a network cell of a mobile terminal according to an embodiment of the present disclosure.

Referring to Fig. 4, an apparatus 400 for accessing a network cell of a mobile terminal may include: a scanning unit 410, a decoding unit 420, a searching unit 430 and a synchronization and accessing unit 440. The scanning unit 410 may scan a specific unlicensed frequency band (such as but not limited to 2.4GHz), in response to the mobile terminal requesting to access the network cell. The decoding unit 420 may decode, in response to obtaining a predetermined signal by scanning, the predetermined signal. The searching unit 430 may search for a cell synchronization signal, based on a decoding result. The synchronization and accessing unit 440 may complete downlink synchronization and access the network cell, based on the searched cell synchronization signal.

More specifically, the decoding unit 420 may measure a signal strength of a signal obtained by scanning the specific unlicensed frequency band, and determine the obtained signal as the predetermined signal, in response to the measured signal strength being greater than a predetermined threshold. A scanning duration for scanning the specific unlicensed frequency band is a sum of a transmission time slot and a dormant time slot of the predetermined signal, which are set in advance. A duration of the transmission time slot may be, for example, 10ms, a duration of the dormant time slot is dynamically adjustable. Generally speaking, a duration of the dormant time slot may be, for example, 80ms-300ms.

The decoding unit 420 may decode the predetermined signal in a specific decoding scheme, and extract frequency channel information for accessing the network cell from the decoded predetermined signal. For example, the decoding unit 420 may perform QPSK demodulation on the predetermined signal to obtain a corresponding bit stream, then position the bit stream to obtain a frame delimiter of the bit stream, and finally in response to the frame delimiter of the bit stream being the same as a preset symbol, extract the frequency channel information for accessing the network cell from the bit stream.

The searching unit 430 may search for the cell synchronization signal to acquire a physical cell identity of a cell, based on the extracted frequency channel information for accessing the network cell. The synchronization and accessing unit 440 may complete downlink synchronization between the mobile terminal and a base station, based on the acquired physical cell identity, and initiate a random access procedure to access the network cell, after completing the downlink synchronization.

Alternatively, the synchronization and accessing unit 440 may perform a system scan and/or a full band scan to access the network cell, in response to the scanning unit 410 failing to obtain the predetermined signal by scanning and/or the searching unit 430 failing to find the cell synchronization signal. In addition, the synchronization and accessing unit 440 may perform a system scan and/or a full band scan to access the network cell, in response to the frame delimiter of the bit stream obtained by decoding by the decoding unit 420 being different from the preset symbol.

Fig. 5 is a block diagram showing an apparatus for accessing a mobile terminal of a base station according to an embodiment of the present disclosure.

Referring to Fig. 5, an apparatus 500 for accessing a mobile terminal of a base station may include: a broadcasting unit 510 and an accessing unit 520. The broadcasting unit 510 may broadcast periodically a predetermined signal including frequency channel information for accessing a network cell covered by the base station on a specific unlicensed frequency band (such as but not limited to 2.4GHz). The accessing unit 520 may interact with the mobile terminal to complete the mobile terminal accessing to the network cell covered by the base station, in response to the mobile terminal initiating a random access procedure for the network cell covered by the base station based on the predetermined signal.

According to an embodiment of the present disclosure, the predetermined signal may be acquired by encoding a bit stream including the frequency channel information for accessing the network cell. More specifically, the predetermined signal may be acquired by QPSK encoding the bit stream including the frequency channel information for accessing the network cell. Here, the bit stream may include a frame delimiter, information indicating the number of frequency channels of the network cell covered by the base station, k+1 CRC check (cyclic redundancy check) information and frequency channel information of k frequency channels, where k is the number of frequency channels of the network cell covered by the base station.

In addition, in the broadcasting unit 510, a period of the predetermined signal including the frequency channel information for accessing the network cell broadcasting on the specific unlicensed frequency band may be composed of a transmission time slot for transmitting the predetermined signal and a dormant time slot. A duration of the transmission time slot may be, for example, 10ms, a duration of the dormant time slot is dynamically adjustable. Generally speaking, a duration of the dormant time slot may be, for example, 80ms-300ms.

Referring to Fig. 6, a computing apparatus 600 according to an embodiment of the present disclosure may include a processor 610 and a memory 620. The processor 610 may include (but is not limited to) a central processing unit (CPU), a digital signal processor (DSP), a microcomputer, a field programmable gate array (FPGA), a system on chip (SoC), a microprocessor, an application specific integrated circuit (ASIC), etc. The memory 620 stores computer programs to be executed by the processor 610. The memory 620 includes a high-speed random access memory and/or a non-volatile computer-readable storage medium. When the processor 610 executes the computer programs stored in the memory 620, the method for accessing a network cell by a mobile terminal or the method for accessing a mobile terminal by a base station as described above may be implemented.

The method for accessing a network cell by a mobile terminal and the method for accessing a mobile terminal by a base station according to the embodiments of the present disclosure may be written as computer programs and stored on the computer-readable storage medium. When the computer programs are executed by the processor, the method for accessing a network cell by a mobile terminal or the method for accessing a mobile terminal by a base station as described above may be implemented. Examples of the computer-readable storage medium include: read only memory (ROM), random access programmable read only memory (PROM), electrically erasable programmable read only memory (EEPROM), random access memory (RAM), dynamic random access memory (DRAM), static random access memory (SRAM), flash memory, non-volatile memory, CD-ROM, CD-R, CD+R, CD-RW, CD+RW, DVD-ROM, DVD-R, DVD+R, DVD-RW, DVD+RW, DVD-RAM, BD-ROM, BD-R, BD-R LTH, BD-RE, Blu-ray or CD storage, hard disk drive (HDD), solid state drive (SSD), card storage (such as multimedia cards, secure digital (SD) cards, or extreme digital (XD) cards), magnetic tape, floppy disk, magneto-optical data storage apparatus, optical data storage apparatus, hard disk, solid state disk, and any other apparatuses. The any other apparatuses are configured to store the computer programs and any associated data, data files and data structures in a non-transitory mode and provide the computer programs and any associated data, data files and data structures to the processor or computer, enabling the processor or computer to execute the computer programs. In one example, the computer programs and any associated data, data files and data structures are distributed on a networked computer system, so that the computer programs and any associated data, data files and data structures are stored, accessed, and executed in a distributed mode through one or more processors or computers.

Compared with the existing network search method, the method for accessing a network cell by a mobile terminal, the method for accessing a mobile terminal by a base station, the apparatus for accessing a network cell of a mobile terminal, and the apparatus for accessing a mobile terminal of a base station according to the present disclosure, may greatly save network search time, improve network search speed, optimize the efficiency of network recovery after network loss, and complete wireless network access extremely quickly.

Although some embodiments of the present disclosure have been shown and described, those skilled in the art should understand that these embodiments may be modified without departing from the principle and spirit of the present disclosure whose scope is defined by the claims and their equivalents.

Claims

A method for accessing a network cell by a mobile terminal, the method comprising:

scanning a specific unlicensed frequency band, in response to the mobile terminal requesting to access the network cell;

decoding, in response to obtaining a predetermined signal by scanning, the predetermined signal;

searching for a cell synchronization signal, based on a decoding result; and

completing downlink synchronization and accessing the network cell, based on the searched cell synchronization signal.
The method according to claim 1, wherein the scanning a specific unlicensed frequency band comprises:

measuring a signal strength of a signal obtained by scanning the specific unlicensed frequency band; and

determining the obtained signal as the predetermined signal, in response to the measured signal strength being greater than a predetermined threshold.
The method according to claim 1, wherein the decoding the predetermined signal comprises:

decoding the predetermined signal with a specific decoding scheme, and

extracting frequency channel information for accessing the network cell from the decoded predetermined signal.
The method according to claim 3, wherein the decoding the predetermined signal comprises:

performing QPSK demodulation on the predetermined signal to obtain a corresponding bit stream;

positioning the bit stream to obtain a frame delimiter of the bit stream; and

extracting the frequency channel information for accessing the network cell from the bit stream, in response to the frame delimiter of the bit stream being the same as a preset symbol.
The method according to claim 4, wherein the method further comprises:

performing a system scan and/or a full band scan to access the network cell, in response to the frame delimiter of the bit stream being different from the preset symbol.
The method according to claim 3, wherein the searching for a cell synchronization signal, based on a decoding result comprises:

searching for the cell synchronization signal to acquire a physical cell identity of a cell, based on the extracted frequency channel information for accessing the network cell.
The method according to claim 6, wherein the completing downlink synchronization and accessing the network cell, based on the searched cell synchronization signal comprises:

completing downlink synchronization between the mobile terminal and a base station, based on the acquired physical cell identity; and

initiating a random access procedure to access the network cell, after completing the downlink synchronization.
The method according to claim 1, wherein the method further comprises:

performing a system scan and/or a full band scan to access the network cell, in response to failing to obtain the predetermined signal by scanning and/or failing to find the cell synchronization signal.
A method for accessing a mobile terminal by a base station, the method comprising:

broadcasting periodically a predetermined signal comprising frequency channel information for accessing a network cell covered by the base station on a specific unlicensed frequency band; and

interacting with the mobile terminal to complete the mobile terminal accessing to the network cell covered by the base station, in response to the mobile terminal initiating a random access procedure for the network cell covered by the base station based on the predetermined signal.
The method according to claim 9, wherein the predetermined signal is acquired by encoding a bit stream including the frequency channel information for accessing the network cell.
The method according to claim 10, wherein the predetermined signal is acquired by QPSK encoding the bit stream including the frequency channel information for accessing the network cell.
The method according to claim 10, wherein the bit stream comprises a frame delimiter, information indicating a number of frequency channels of the network cell covered by the base station, k+1 CRC check information, and frequency channel information of k frequency channels, wherein k is the number of frequency channels of the network cell covered by the base station.
The method according to claim 9, wherein a period of the predetermined signal comprising the frequency channel information for accessing the network cell broadcasting on the specific unlicensed frequency band is composed of a transmission time slot for transmitting the predetermined signal and a dormant time slot.
A mobile terminal for accessing a network cell, the mobile terminal comprising:

a scanning unit, configured to scan a specific unlicensed frequency band, in response to the mobile terminal requesting to access the network cell;

a decoding unit, configure to decode, in response to obtaining a predetermined signal by scanning, the predetermined signal;

a searching unit, configure to search for a cell synchronization signal, based on a decoding result; and

a synchronization and accessing unit, configured to complete downlink synchronization and access the network cell, based on the searched cell synchronization signal.
A base station for accessing a mobile terminal, the base station comprising:

a broadcasting unit, configured to broadcast periodically a predetermined signal comprising frequency channel information for accessing a network cell covered by the base station on a specific unlicensed frequency band; and

an accessing unit, configured to interact with the mobile terminal to complete the mobile terminal accessing to the network cell covered by the base station, in response to the mobile terminal initiating a random access procedure for the network cell covered by the base station based on the predetermined signal.