CN112954748B - Physical random access channel resource allocation and random access method and equipment - Google Patents

Abstract

The invention discloses a physical random access channel resource allocation and random access method and equipment, comprising the following steps: the base station determines the number of terminals to be switched and the switching time; when the number of the terminals and the switching time exceed a preset threshold, reserving large bandwidth uplink resources and/or short period uplink resources as physical random access channel resources for the terminals to initiate random access; and after the switching is finished, releasing the reserved physical random access channel resources. The terminal determines the physical random access channel resource capable of initiating random access, the terminal initiates random access on the special configuration resource of the physical random access channel, and initiates competitive random access on the public configuration resource of the physical random access channel after the disconnection. By adopting the method and the device, the high-capacity terminal can be ensured to be rapidly switched when being switched on the high-speed rail, and the user performance and experience are improved.

Description

Physical random access channel resource configuration and random access methods and equipment

Technical field

The present invention relates to the field of wireless communication technology, and in particular to a physical random access channel resource configuration and random access method and equipment.

Background technique

The resource allocation of 5G NR (next generation radio) PRACH (Physical Random Access Channel) is as shown in the following table in TR38.211 Table6.3.3.2-3:

First, according to the IERACH-ConfigDedicated (RACH dedicated configuration information element; IE: Information element, Information Element; RACH: Random Access Channel, Physical Random Access Channel) in the RRC (Radio Resource Control) reconfiguration message issued by the base station, The prach-ConfigurationIndex (PRACH configuration creation index) defined by the information rach-ConfigGeneric (RACH configuration generic) obtains the PRACH serial number. Figure 1 is a schematic diagram of the PRACH configuration method. The PRACH sequence number corresponding to the PRACH selection process is shown in the figure.

The terminal obtains prach-ConfigurationIndex through the RRC reconfiguration message and obtains PRACH time domain location information. The PRACH time domain period 160ms/80ms/40ms/20ms/10ms is obtained according to the prach sequence number SFN (System Frame Number) related information, the subframe number 0~9 is obtained through the Subframe number, and the PRACH time is obtained through the Starting symbol The starting position of the domain is 0 or 7. The duration of the PRACH sequence obtained through the Number of PRACH slots within a subframe is 1 to 2 slots (time slots). The PRACH time domain burst (burst) is obtained through the number of time-domainPRACH occasions within a PRACH slot. The number of symbols sent) is 1/2/3/6, and the number of symbols occupied by PRACH time domain obtained through PRACHduration is 2/4/6/12 symbols. At the same time, prach-ConfigurationIndex corresponds to different PRACH formats.

The terminal obtains msg1-SubcarrierSpacing (message 1-subcarrier spacing), msg1-FrequencyStart (message 1-start frequency) and msg1-FDM (message 1-orthogonal frequency division) through the RRC reconfiguration message; FDM: frequency division multiplexing, Frequency Division Multiplexing) to obtain the subcarrier spacing, frequency domain starting position and frequency division multiplexing mode of PRACH.

The shortcoming of the existing technology is that under the current PRACH resource allocation mechanism, uplink resources are wasted.

Contents of the invention

The present invention provides a physical random access channel resource configuration and random access method and equipment to solve the problem of waste of uplink resources under the current PRACH resource allocation mechanism.

An embodiment of the present invention provides a PRACH resource configuration method, which includes:

The base station determines the number of terminals that need to be switched and the switching time;

When the number of terminals and handover time exceed the preset threshold, large-bandwidth uplink resources and/or short-period uplink resources are reserved as PRACH resources for terminals to initiate random access;

After the handover is completed, the reserved PRACH resources are released.

In implementation, the number of terminals that need to be switched and the switching time are determined based on the time and number of MRs sent by each terminal.

In implementation, the PRACH resources include:

The terminal obtains RACH-ConfigCommon resources by monitoring the cell MIB, and/or specifies RACH-ConfigDedicated resources through RRC reconfiguration.

In the implementation, it further includes configuring the RACH-ConfigDedicated resources in the PRACH resources in one of the following ways or a combination thereof:

Configure the usage period of PRACH resources to be infinite;

Configure multiple sets of PRACH resources for each terminal;

Configure the usage time and release time of PRACH resources.

In the implementation, to configure the usage period of the PRACH resource to be infinite is to set x in n _SFN mod x=y to a maximum value.

In the implementation, to configure multiple sets of PRACH resources for each terminal is to configure multiple sets of prach-Configuration Index for the terminal, set y in n _SFN mod x=y of each set to different values, and configure ra-OccasionList through RRC Multiple sets of PRACH resources.

In the implementation, to configure the use time and release time of PRACH resources, msg1-duration is added to the RACH-Config Generic in IERACH-ConfigDedicated to configure the use time and release time of PRACH. Among them, msg1-duration is the use of MSG1. Time, the starting time point of msg1-duration is the time point when the terminal sends MSG for the first time. After the usage time of MSG1 is exceeded, the PRACH corresponding to msg1-duration is released.

In implementation, the RACH-ConfigCommon resource in the PRACH resource is used for contention random access after the terminal is disconnected.

Implementation further includes:

After receiving msg1 sent by the terminal in the same sequence at each burst position of the subframe, diversity gain is performed.

In implementation, the time-frequency domain resources of the PRACH resources are:

The time domain of the uplink time slot is full, or half of the resources are occupied in each time slot;

There are 8 frequency divisions in the frequency domain, and 4 to 8 different sets of PRACH resources in the frequency domain are obtained according to msg1-FrequencyStart.

Implementation further includes:

Group the PRACH resources;

Each terminal is assigned to a different PRACH resource group.

In implementation, the FDM of each PRACH resource group is 8, and each resource block contains 40 to 50 non-contention resolution sequences.

An embodiment of the present invention provides a random access method, including:

The terminal determines the PRACH resources that can initiate random access, where the PRACH resources include: RACH-ConfigCommon resources obtained by the terminal by monitoring the cell MIB, and/or RACH-ConfigDedicated resources determined by the terminal through RRC reconfiguration;

The terminal initiates random access on the RACH-ConfigDedicated resource, and initiates competition random access on the RACH-ConfigCommon resource after being disconnected.

In implementation, the terminal initiates random access on the RACH-ConfigDedicated resource in one of the following ways or a combination thereof:

When the usage period of the PRACH resource is configured to be infinite, access is performed through RRC reconnection after access failure;

When the terminal is configured with multiple sets of PRACH resources, after access to one set of PRACH resources fails, random access is initiated on the next set of PRACH resources;

When the PRACH resource is configured with a usage time and a release time, access is performed through RRC reconnection after access failure.

In implementation, when the terminal determines that x in n _SFN mod x=y is set to a maximum value, it determines that the usage period of the PRACH resource is configured to be infinite.

During implementation, the terminal determines that the terminal is configured with multiple sets of PRACH resources based on the ra-OccasionList configured in the RRC;

When the terminal initiates random access in each set of PRACH resources, it initiates random access according to y in n _SFN mod x=y of each set.

During implementation, when the terminal determines that there is msg1-duration configuring the usage time and release time of PRACH in RACH-ConfigGeneric in IE RACH-ConfigDedicated, it determines that the PRACH resource is configured with usage time and release time, where msg1-duration is this The usage time of MSG1 and the starting time point of msg1-duration are the time points when the terminal sends MSG for the first time. After the usage time of MSG1 is exceeded, the PRACH corresponding to msg1-duration is released.

Implementation further includes:

The terminal uses msg1 sent in the same sequence at each burst position of the subframe.

An embodiment of the present invention provides a base station, including:

Processor, used to read the program in the memory and perform the following processes:

Determine the number of terminals that need to be switched and the switching time;

When the number of terminals and handover time exceed the preset threshold, large-bandwidth uplink resources and/or short-period uplink resources are reserved as PRACH resources for terminals to initiate random access;

After the handover is completed, release the reserved PRACH resources;

Transceiver, used to receive and send data under the control of a processor.

In implementation, the number of terminals that need to be switched and the switching time are determined based on the time and number of MRs sent by each terminal.

In implementation, the PRACH resources include:

The terminal obtains RACH-ConfigCommon resources by monitoring the cell MIB, and/or specifies RACH-ConfigDedicated resources through RRC reconfiguration.

In the implementation, it further includes configuring the RACH-ConfigDedicated resources in the PRACH resources in one of the following ways or a combination thereof:

Configure the usage period of PRACH resources to be infinite;

Configure multiple sets of PRACH resources for each terminal;

Configure the usage time and release time of PRACH resources.

In the implementation, to configure the usage period of the PRACH resource to be infinite is to set x in n _SFN mod x=y to a maximum value.

In the implementation, to configure multiple sets of PRACH resources for each terminal is to configure multiple sets of prach-Configuration Index for the terminal, set y in n _SFN mod x=y of each set to different values, and configure ra-OccasionList through RRC Multiple sets of PRACH resources.

In the implementation, to configure the use time and release time of PRACH resources, msg1-duration is added to the RACH-Config Generic in IERACH-ConfigDedicated to configure the use time and release time of PRACH. Among them, msg1-duration is the use of MSG1. Time, the starting time point of msg1-duration is the time point when the terminal sends MSG for the first time. After the usage time of MSG1 is exceeded, the PRACH corresponding to msg1-duration is released.

In implementation, the RACH-ConfigCommon resource in the PRACH resource is used for contention random access after the terminal is disconnected.

Implementation further includes:

After receiving msg1 sent by the terminal in the same sequence at each burst position of the subframe, diversity gain is performed.

In implementation, the time-frequency domain resources of the PRACH resources are:

The time domain of the uplink time slot is full, or half of the resources are occupied in each time slot;

There are 8 frequency divisions in the frequency domain, and 4 to 8 different sets of PRACH resources in the frequency domain are obtained according to msg1-FrequencyStart.

Implementation further includes:

Group the PRACH resources;

Each terminal is assigned to a different PRACH resource group.

In implementation, the FDM of each PRACH resource group is 8, and each resource block contains 40 to 50 non-contention resolution sequences.

An embodiment of the present invention provides a base station, including:

Determination module, used to determine the number of terminals that need to be switched and the switching time;

The reservation module is used to reserve large-bandwidth uplink resources and/or short-period uplink resources as PRACH resources for terminals to initiate random access when the number of terminals and handover time exceed the preset threshold;

A release module, configured to release the reserved PRACH resources after the handover is completed.

In implementation, the determination module is further used to determine the number of terminals that need to be switched and the switching time based on the time and quantity of each terminal sending MR.

In implementation, the reservation module is further used to reserve RACH-ConfigCommon resources obtained by the terminal by monitoring the cell MIB, and/or specify RACH-ConfigDedicated resources through RRC reconfiguration.

In implementation, the reservation module is further configured to configure the RACH-ConfigDedicated resources in the PRACH resources in one of the following ways or a combination thereof:

Configure the usage period of PRACH resources to be infinite;

Configure multiple sets of PRACH resources for each terminal;

Configure the usage time and release time of PRACH resources.

In the implementation, to configure the usage period of the PRACH resource to be infinite is to set x in n _SFN mod x=y to a maximum value.

During implementation, the reservation module is further used to configure multiple sets of PRACH resources for each terminal. It configures multiple sets of prach-Configuration Index for the terminal, sets y in n _SFN mod x=y of each set to different values, and passes RRC configures ra-OccasionList to configure multiple sets of PRACH resources.

During implementation, the reservation module is further used to configure the usage time and release time of PRACH resources. msg1-duration is added to RACH-Config Generic in IERACH-ConfigDedicated to configure the usage time and release time of PRACH, where msg1- duration is the usage time of MSG1. The starting time point of msg1-duration is the time point when the terminal sends MSG for the first time. After the usage time of MSG1 is exceeded, the PRACH corresponding to msg1-duration is released.

In implementation, the reservation module is further configured to reserve RACH-ConfigCommon resources in the PRACH resources for contention random access after the terminal goes offline.

In the implementation, the release module is further used to perform diversity gain after receiving msg1 sent by the terminal in the same sequence at each burst position of the subframe.

In implementation, the reservation module is further used to reserve the time-frequency domain resources of the PRACH resources as:

The time domain of the uplink time slot is full, or half of the resources are occupied in each time slot;

There are 8 frequency divisions in the frequency domain, and 4 to 8 different sets of PRACH resources in the frequency domain are obtained according to msg1-FrequencyStart.

In implementation, the reserved module is further used for:

Group the PRACH resources;

Each terminal is assigned to a different PRACH resource group.

In implementation, the FDM of each PRACH resource group is 8, and each resource block contains 40 to 50 non-contention resolution sequences.

An embodiment of the present invention provides a terminal, including:

Processor, used to read the program in the memory and perform the following processes:

Determine the PRACH resources that can initiate random access, where the PRACH resources include: RACH-ConfigCommon resources obtained by the terminal by monitoring the cell MIB, and/or RACH-ConfigDedicated resources determined by the terminal through RRC reconfiguration;

Initiate random access on the RACH-ConfigDedicated resource, and initiate competition random access on the RACH-ConfigCommon resource after being dropped;

Transceiver, used to receive and send data under the control of a processor.

In implementation, random access is initiated on the RACH-ConfigDedicated resource in one of the following ways or a combination thereof:

When the usage period of the PRACH resource is configured to be infinite, access is performed through RRC reconnection after access failure;

When the terminal is configured with multiple sets of PRACH resources, after access to one set of PRACH resources fails, random access is initiated on the next set of PRACH resources;

When the PRACH resource is configured with a usage time and a release time, access is performed through RRC reconnection after access failure.

In implementation, when it is determined that x in n _SFN mod x=y is set to a maximum value, it is determined that the usage period of the PRACH resource is configured to be infinite.

During implementation, it is determined based on the ra-OccasionList configured by RRC that the terminal is configured with multiple sets of PRACH resources;

When random access is initiated for each set of PRACH resources, random access is initiated according to y in n _SFN mod x=y of each set.

During the implementation, when it is determined that the RACH-Config Generic in IE RACH-ConfigDedicated contains msg1-duration that configures the usage time and release time of PRACH, it is determined that the PRACH resource is configured with usage time and release time, where msg1-duration is this The usage time of MSG1 and the starting time point of msg1-duration are the time points when the terminal sends MSG for the first time. After the usage time of MSG1 is exceeded, the PRACH corresponding to msg1-duration is released.

Implementation further includes:

msg1 is sent in the same sequence at each burst position of the subframe.

An embodiment of the present invention provides a terminal, including:

Resource determination module, used to determine PRACH resources that can initiate random access, wherein the PRACH resources include: RACH-ConfigCommon resources obtained by the terminal by monitoring the cell MIB, and/or RACH-ConfigDedicated determined by the terminal through RRC reconfiguration resource;

An access module, configured to initiate random access on the RACH-ConfigDedicated resource, and initiate competition random access on the RACH-ConfigCommon resource after being disconnected.

In implementation, the access module is further configured to initiate random access on the RACH-ConfigDedicated resource in one of the following ways or a combination thereof:

When the usage period of the PRACH resource is configured to be infinite, access is performed through RRC reconnection after access failure;

When the terminal is configured with multiple sets of PRACH resources, after access to one set of PRACH resources fails, random access is initiated on the next set of PRACH resources;

When the PRACH resource is configured with a usage time and a release time, access is performed through RRC reconnection after access failure.

In implementation, the resource determination module is further configured to determine that the usage period of the PRACH resource is configured to be infinite when it is determined that x in n _SFN mod x=y is set to a maximum value.

During implementation, the resource determination module is further used to determine whether the terminal is configured with multiple sets of PRACH resources based on the ra-OccasionList configured by the RRC;

The access module is further configured to initiate random access according to y in n _SFN mod x=y of each set of PRACH resources when random access is initiated.

During implementation, the resource determination module is further used to determine that the PRACH resource configuration has a usage time and a release time when it is determined that the msg1-duration of the RACH-Config Generic in the IE RACH-ConfigDedicated contains the usage time and release time of the PRACH, where , msg1-duration is the usage time of MSG1. The starting time point of msg1-duration is the time point when the terminal sends MSG for the first time. After the usage time of MSG1 is exceeded, the PRACH corresponding to msg1-duration is released.

In the implementation, the access module is further used to use msg1 sent in the same sequence at each burst position of the subframe.

An embodiment of the present invention provides a computer-readable storage medium, which stores a computer program for executing the above-mentioned PRACH resource configuration method and/or random access method.

The beneficial effects of the present invention are as follows:

In the technical solution provided by the embodiment of the present invention, when it is determined based on the number of terminals and the switching time that several terminals similar to high-speed railways will switch at the same time, large-bandwidth uplink resources and/or short-cycle uplink resources will be reserved as terminals. Initiate the PRACH resources of random access, and after the handover is completed, this part of the reserved PRACH resources will be released. Due to the dynamic adjustment of the PRACH resource configuration during handover and the static configuration of the access resource configuration during non-access, as well as the increase in handover time The number of PRACH resources ensures rapid switching of large-capacity terminals during high-speed rail switching, improving user performance and experience.

Description of drawings

The drawings described here are used to provide a further understanding of the present invention and constitute a part of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the attached picture:

Figure 1 is a schematic diagram of the PRACH configuration method in the background technology;

Figure 2 is a schematic flow chart of the implementation of the PRACH resource configuration method on the base station side in the embodiment of the present invention;

Figure 3 is a schematic flowchart of the random access method implementation on the terminal side in an embodiment of the present invention;

Figure 4 is a schematic diagram of the switching process implementation in the embodiment of the present invention;

Figure 5 is a schematic structural diagram of a base station in an embodiment of the present invention;

Figure 6 is a schematic structural diagram of a terminal in an embodiment of the present invention.

Detailed ways

The inventor noticed during the invention process:

Currently, PRACH resources are divided into handover random access resources and non-handover random access resources (such as resident-initiated services or disconnection re-access). Existing PRACH resource configurations are static configurations. The base station uses SSB (synchronization signal block, Synchronization Signal Block) or RRC reconfiguration message tells the terminal the location of the PRACH resource. The terminal uses the known PRACH resource to initiate random access when initiating services or handovers.

The base station reserves uplink resources for PRACH resources to meet the needs of switching and access scenarios at any time when terminals move irregularly in large network environments, ensuring user experience performance. However, in some special scenarios, such as high-speed rail scenarios, unlike large networks, terminals will switch simultaneously with the movement of the car body. The terminal behavior is regular and followable. During most of the driving time, there are no high-speed rail switching users, and the preset uplink PRACH is used. Resources are used for terminal switching access, which causes a great waste of uplink resources and affects the uplink performance of the system.

For example, in order to ensure the access performance of large-capacity users, short-period PRACH resource configuration or broadband long-period PRACH resource configuration can be used. If a short-period PRACH configuration (such as 6 PRBs (physical resource blocks) in 10ms) is used, the access performance of the terminal is guaranteed, but there are fewer users accessing each time and the user waiting time is long (about 200ms), which makes the terminal easy to Dropped. If long-period large-bandwidth PRACH is used with a larger period (such as 160ms 48 PRBs), resource overhead and access delay can be reduced, but it will lead to poor terminal access performance, access waiting delay and access failure. The waiting time to enter is long, and it is easy to get disconnected in high-speed rail scenarios. If a short-period large-bandwidth PRACH configuration is used (such as 48 PRBs in 10ms), the PRACH uplink overhead is 20%, which is too much.

Based on this, the embodiments of this application provide a solution that can be used to dynamically configure PRACH resources in scenarios represented by high-speed railways. In the solution, the base station adopts a dynamic configuration method of PRACH resources. When the terminal switches, in a short time Dynamically schedule more uplink resources for PRACH random access of a large number of terminals. After the handover is completed, the base station releases the handover PRACH resources for uplink service channel transmission. Taking the high-speed rail scenario as an example, it can reduce the handover delay of large-capacity users and improve the success rate of large-capacity user handovers. At the same time, uplink data transmission is not affected by the resources occupied by static PRACH.

Specific embodiments of the present invention will be described below with reference to the accompanying drawings.

During the explanation process, the implementation on the terminal side and the base station side will be described respectively, and then an example of the cooperative implementation of the two will be given to better understand the implementation of the solution given in the embodiment of the present invention. This way of explanation does not mean that the two must be implemented together or separately. In fact, when the terminal and the base station are implemented separately, they also solve the problems on the terminal side and the base station side respectively. When the two are used together, it will Get better technical results.

During the explanation process, the high-speed rail scenario will be mainly used as an example. The high-speed rail is used as an example because this scenario is relatively typical and has high practical application value; however, theoretically speaking, this solution is also It can be used in other scenarios, as long as a large number of terminals need to be switched simultaneously in a short period of time. Therefore, the high-speed rail scenario is only used to teach those skilled in the art how to implement the present invention, but it does not mean that it can only be used in high-speed rail. , which can be applied to corresponding scenarios based on practical needs during the implementation process.

Figure 2 is a schematic implementation flow chart of the PRACH resource configuration method on the base station side. As shown in the figure, it may include:

Step 201: Determine the number of terminals that need to be switched and the switching time;

Step 202: When the number of terminals and the handover time exceed the preset threshold, reserve large-bandwidth uplink resources and/or short-period uplink resources as PRACH resources for terminals to initiate random access;

Step 203: After the handover is completed, release the reserved PRACH resources.

Figure 3 is a schematic diagram of the implementation process of the random access method on the terminal side. As shown in the figure, it may include:

Step 301: Determine the PRACH resources that can initiate random access, where the PRACH resources include: RACH-ConfigCommon resources obtained by the terminal by monitoring the cell MIB, and/or RACH-ConfigDedicated resources determined by the terminal through RRC reconfiguration;

Step 302: The terminal initiates random access on the RACH-ConfigDedicated resource, and after being disconnected, initiates competition random access on the RACH-ConfigCommon resource.

Specifically, PRACH resources are divided into handover random access resources and other random access resources (such as user camping or initiating services). In the solution, random access resources are dynamically configured for handover to ensure that the terminal can access successfully at any time after being offline. Non-handover random resources still reserve uplink resources according to the large network configuration to ensure terminal access performance.

In implementation, the PRACH resources include:

The terminal obtains RACH-ConfigCommon resources by monitoring the cell MIB, and/or specifies RACH-ConfigDedicated resources through RRC reconfiguration.

Specifically, configure two sets of PRACH resources, one set of RACH-ConfigCommon (common configuration RACH) and one set of RACH-ConfigDedicated (dedicated configuration RACH) resources. The two sets of resources belong to different time-frequency domain locations. RACH-ConfigCommon is obtained by listening to the cell MIB (Master Information Block), and RACH-ConfigDedicated is specified by RRC reconfiguration.

RACH-ConfigCommon exists throughout the time, is configured with FDM=1, and has a period of 10ms. It is used for contention access after the terminal is disconnected, and the uplink overhead is 1%.

For high-speed rail scenarios, RACH-ConfigDedicated and RACH-ConfigCommon configure different resources, which can reduce the RACH-ConfigDedicated uplink resource overhead during high-capacity times.

In implementation, on the base station side, the number of terminals that need to be switched and the switching time are determined based on the time and number of MRs sent by each terminal.

Specifically, during the handover process, the base station determines based on the time when users send MR (Measurement Report, Measurement Report) and the number of requesting users. If large-capacity users handover at the same time, the base station reserves PRACH resources and configures short-period PRACH resources for each terminal. Large-capacity users configure large-bandwidth PRACH resources. RACH-ConfigDedicated releases the resources after the configuration is completed, and the base station can use this resource for PUSCH (Physical Uplink Shared Channel) transmission to reduce PRACH uplink overhead. If only occasional individual user handovers occur, the PRACH dedicated resources in RACH-ConfigCommon are used for individual user handover access.

The following describes the configuration of resources

On the base station side, it may further include configuring the RACH-ConfigDedicated resources in the PRACH resources in one of the following ways or a combination thereof:

Configure the usage period of PRACH resources to be infinite;

Configure multiple sets of PRACH resources for each terminal;

Configure the usage time and release time of PRACH resources.

Correspondingly, on the terminal side, the terminal initiates random access on the RACH-ConfigDedicated resource in one of the following ways or a combination thereof:

When the usage period of the PRACH resource is configured to be infinite, access is performed through RRC reconnection after access failure;

When the terminal is configured with multiple sets of PRACH resources, after access to one set of PRACH resources fails, random access is initiated on the next set of PRACH resources;

When the PRACH resource is configured with a usage time and a release time, access is performed through RRC reconnection after access failure.

The three methods are explained in detail below.

1. Configure the usage period of PRACH resources to be infinite.

On the base station side, to configure the usage period of the PRACH resource to be infinite is to set x in n _SFN mod x=y to a maximum value.

Correspondingly, on the terminal side, when the terminal determines that x in n _SFN mod x=y is set to a maximum value, it determines that the usage period of the PRACH resource is configured to be infinite.

Specifically, using the existing PRACH configuration scheme, the PRACH period is configured to be infinite, that is, x is set to a maximum value at n _SFN mod x = y. PRACH is similar to aperiodic transmission, and PRACH resources are only valid once. to indicate that it is aperiodic; where n _SFN is the radio frame where the PRACH resource is located, x is the PRACH cycle, with SFN0 as the starting point, and y is used to calculate the position of the radio frame where the PRACH resource is located within the PRACH cycle.

After adopting this solution, the terminal cannot periodically initiate random access again after the first access failure. It can reconnect through RRC after the link is disconnected, without affecting the terminal performance.

2. Configure multiple sets of PRACH resources for each terminal.

On the base station side, configuring multiple sets of PRACH resources for each terminal is to configure multiple sets of prach-Configuration Index (PRACH configuration index) for the terminal, and set y in n _SFN mod x=y of each set to different values, and pass RRC configures ra-OccasionList to configure multiple sets of PRACH resources.

Correspondingly, on the terminal side it is:

The terminal determines that the terminal is configured with multiple sets of PRACH resources based on the ra-OccasionList configured in the RRC;

When the terminal initiates random access in each set of PRACH resources, it initiates random access according to y in n _SFN mod x=y of each set.

Specifically, multiple sets of prach-Configuration Index can be configured for the terminal, and the n _SFN mod x=yy of each set is set to a different value. After the first access failure, the terminal attempts random access on other PRACH resources. Configure ra-OccasionList (random access opportunity list) through RRC to configure multiple sets of PRACH resources.

In implementation, the existing PRACH format does not support setting a larger value for the PRACH cycle, so the cycle value can be set by adding a new PRACH format.

For high-speed rail scenarios, base stations and terminals can support multiple sets of RACH-ConfigDedicated resource configurations for handover, using the RRC message ra-OccasionList configuration.

For high-speed rail scenarios, configure the new PRACH time domain period to be aperiodic, configure the SFN x to a maximum value, and support configuring multiple sets of PRACH resources to the terminal, so that when one PRACH access fails, other PRACH resources can be used. Reconnect.

3. Configure the usage time and release time of PRACH resources.

On the base station side, to configure the usage time and release time of PRACH resources, add msg1-duration in RACH-Config Generic in IERACH-ConfigDedicated to configure the usage time and release time of PRACH, where msg1-duration is the value of MSG1 Usage time, the starting time point of msg1-duration is the time point when the terminal sends MSG for the first time. After the usage time of MSG1 is exceeded, the PRACH corresponding to msg1-duration is released.

Correspondingly, on the terminal side: when the terminal determines that there is msg1-duration configuring the use time and release time of PRACH in the RACH-Config Generic in IE RACH-ConfigDedicated, it determines that the PRACH resource is configured with use time and release time, Among them, msg1-duration is the usage time of MSG1, and the starting time point of msg1-duration is the time point when the terminal sends MSG for the first time. After the usage time of MSG1 is exceeded, the PRACH corresponding to msg1-duration is released.

Specifically, the RRC reconfiguration message can be added, and msg1-duration (message 1-period) is added to the RACH-ConfigGeneric of the IE RACH-ConfigDedicated information to indicate the usage time of this MSG1. The starting time point is the first time the terminal sends After the MSG (message) time point exceeds the msg1-duration time, PRACH is used to release random resources for handover. If the terminal still fails to handover successfully, it can use RRC reconnection mode to access.

For high-speed rail scenarios, configure the RACH-ConfigDedicated effective time, configure MSG1-duration in the RRC reconfiguration message, and maintain the effective time of MSG1 during handover. When the time expires, the base station releases the PRACH resources used for handover for subsequent uplink resource transmission. .

In implementation, on the base station side, it may further include:

After receiving msg1 sent by the terminal in the same sequence at each burst position of the subframe, diversity gain is performed.

Correspondingly, the terminal side may further include:

The terminal uses msg1 sent in the same sequence at each burst position of the subframe.

Specifically, if there are two burst positions in a subframe, the terminal uses the same sequence to send msg1 at each position, and the base station performs diversity gain after receiving it to enhance the access performance in high-speed rail scenarios.

In implementation, the time-frequency domain resources of the PRACH resources may be:

The time domain of the uplink time slot is full, or half of the resources are occupied in each time slot;

There are 8 frequency divisions in the frequency domain, and 4 to 8 different sets of PRACH resources in the frequency domain are obtained according to msg1-FrequencyStart.

Specifically, PRACH time and frequency domain resources can be configured as follows:

PRACH occupies the time domain of the uplink time slot, or occupies half of the resources in each time slot, and is divided into 8 frequencies in the frequency domain. At the same time, 4 to 8 different sets of PRACH resources in the frequency domain are obtained according to msg1-FrequencyStart (message 1-start frequency). .

During implementation, it may further include:

Group the PRACH resources;

Each terminal is assigned to a different PRACH resource group.

In a specific implementation, the FDM of each PRACH resource group is 8, and each resource block contains 40 to 50 non-contention resolution sequences.

Specifically, the base station can group the terminals into different PRACH resource groups according to the order of sending the measurement reports. Each group has FDM=8, and each resource block contains 40 to 50 non-contention resolution sequences.

For high-speed rail scenarios, the base station reserves multiple sets of PRACH resources and groups different PRACH resources for terminals according to the terminal's measurement and reporting time to ensure staggered access of terminals, improve access success rate, and reduce access waiting delay. The staggering process can use the first-in-first-out method to allocate PRACH resources, or the average grouping method to allocate PRACH resources.

For high-speed rail scenarios, MSG1-FDM is configured with a maximum number of 8, which can increase PRACH resources in the same subframe and reduce PRACH access delay.

The following uses an example to illustrate the overall allocation of PRACH resource configuration.

Figure 4 is a schematic diagram of the handover process implementation. As shown in the figure, handover may include:

Step 401: The base station receives the measurement report and prepares for handover.

Step 402: After completing handover preparations, the base station sends a handover command and reserves large-bandwidth short-period uplink resources for PRACH transmission.

Step 403: The base station groups the terminals into different PRACH resource groups according to the order of sending the measurement reports.

Each PRACH resource group group has FDM=8, and each resource block contains 40 to 50 non-contention resolution sequences.

Step 404: After receiving the handover request for RRC reconfiguration, the terminal initiates random access on different PRACH time and frequency domain resources.

Step 405: After all terminals complete the handover, the PRACH resources based on MSG1-duration time out, and the base station releases the random access PRACH resources.

The completion of the handover includes the success or failure of the physical handover. After the PRACH resource based on MSG1-duration times out, the base station releases the random access PRACH resource and starts to use it for uplink service scheduling.

During the handover, since the PRACH resources occupy less than 20%, the remaining resources can be used for uplink service transmission of other users. PRACH handover resources are dynamically configured again during the next handover.

Based on the same inventive concept, embodiments of the present invention also provide a base station, user equipment, and computer-readable storage media. Since the principles and methods of solving problems of these devices are similar, the implementation of these devices can be found in PRACH resource configuration method, The implementation of the random access method will not be repeated again.

When implementing the technical solution provided by the embodiment of the present invention, it can be implemented in the following manner.

Figure 5 is a schematic structural diagram of a base station. As shown in the figure, the base station includes:

The processor 500 is used to read the program in the memory 520 and perform the following processes:

Determine the number of terminals that need to be switched and the switching time;

When the number of terminals and handover time exceed the preset threshold, large-bandwidth uplink resources and/or short-period uplink resources are reserved as PRACH resources for terminals to initiate random access;

After the handover is completed, release the reserved PRACH resources;

Transceiver 510 for receiving and transmitting data under the control of processor 500.

In implementation, the number of terminals that need to be switched and the switching time are determined based on the time and number of MRs sent by each terminal.

In implementation, the PRACH resources include:

The terminal obtains RACH-ConfigCommon resources by monitoring the cell MIB, and/or specifies RACH-ConfigDedicated resources through RRC reconfiguration.

In the implementation, it further includes configuring the RACH-ConfigDedicated resources in the PRACH resources in one of the following ways or a combination thereof:

Configure the usage period of PRACH resources to be infinite;

Configure multiple sets of PRACH resources for each terminal;

Configure the usage time and release time of PRACH resources.

In the implementation, to configure the usage period of the PRACH resource to be infinite is to set x in n _SFN mod x=y to a maximum value.

In the implementation, to configure multiple sets of PRACH resources for each terminal is to configure multiple sets of prach-Configuration Index for the terminal, set y in n _SFN mod x=y of each set to different values, and configure ra-OccasionList through RRC Multiple sets of PRACH resources.

In the implementation, to configure the use time and release time of PRACH resources, msg1-duration is added to the RACH-Config Generic in IERACH-ConfigDedicated to configure the use time and release time of PRACH. Among them, msg1-duration is the use of MSG1. Time, the starting time point of msg1-duration is the time point when the terminal sends MSG for the first time. After the usage time of MSG1 is exceeded, the PRACH corresponding to msg1-duration is released.

In implementation, the RACH-ConfigCommon resource in the PRACH resource is used for contention random access after the terminal is disconnected.

Implementation further includes:

After receiving msg1 sent by the terminal in the same sequence at each burst position of the subframe, diversity gain is performed.

In implementation, the time-frequency domain resources of the PRACH resources are:

The time domain of the uplink time slot is full, or half of the resources are occupied in each time slot;

There are 8 frequency divisions in the frequency domain, and 4 to 8 different sets of PRACH resources in the frequency domain are obtained according to msg1-FrequencyStart.

Implementation further includes:

Group the PRACH resources;

Each terminal is assigned to a different PRACH resource group.

In implementation, the FDM of each PRACH resource group is 8, and each resource block contains 40 to 50 non-contention resolution sequences.

In FIG. 5 , the bus architecture may include any number of interconnected buses and bridges, specifically one or more processors represented by processor 500 and various circuits of the memory represented by memory 520 are linked together. The bus architecture can also link together various other circuits such as peripherals, voltage regulators, and power management circuits, which are all well known in the art and therefore will not be described further herein. The bus interface provides the interface. Transceiver 510 may be a plurality of elements, including a transmitter and a receiver, providing a unit for communicating with various other devices over a transmission medium. The processor 500 is responsible for managing the bus architecture and general processing, and the memory 520 can store data used by the processor 500 when performing operations.

An embodiment of the present invention provides a base station, including:

Determination module, used to determine the number of terminals that need to be switched and the switching time;

The reservation module is used to reserve large-bandwidth uplink resources and/or short-period uplink resources as PRACH resources for terminals to initiate random access when the number of terminals and handover time exceed the preset threshold;

A release module, configured to release the reserved PRACH resources after the handover is completed.

In implementation, the determination module is further used to determine the number of terminals that need to be switched and the switching time based on the time and quantity of each terminal sending MR.

In implementation, the reservation module is further used to reserve RACH-ConfigCommon resources obtained by the terminal by monitoring the cell MIB, and/or specify RACH-ConfigDedicated resources through RRC reconfiguration.

In implementation, the reservation module is further configured to configure the RACH-ConfigDedicated resources in the PRACH resources in one of the following ways or a combination thereof:

Configure the usage period of PRACH resources to be infinite;

Configure multiple sets of PRACH resources for each terminal;

Configure the usage time and release time of PRACH resources.

In the implementation, to configure the usage period of the PRACH resource to be infinite is to set x in n _SFN mod x=y to a maximum value.

During implementation, the reservation module is further used to configure multiple sets of PRACH resources for each terminal. It configures multiple sets of prach-Configuration Index for the terminal, sets y in n _SFN mod x=y of each set to different values, and passes RRC configures ra-OccasionList to configure multiple sets of PRACH resources.

During implementation, the reservation module is further used to configure the usage time and release time of PRACH resources. msg1-duration is added to RACH-Config Generic in IERACH-ConfigDedicated to configure the usage time and release time of PRACH, where msg1- duration is the usage time of MSG1. The starting time point of msg1-duration is the time point when the terminal sends MSG for the first time. After the usage time of MSG1 is exceeded, the PRACH corresponding to msg1-duration is released.

In implementation, the reservation module is further configured to reserve RACH-ConfigCommon resources in the PRACH resources for contention random access after the terminal goes offline.

In the implementation, the release module is further used to perform diversity gain after receiving msg1 sent by the terminal in the same sequence at each burst position of the subframe.

In implementation, the reservation module is further used to reserve the time-frequency domain resources of the PRACH resources as:

The time domain of the uplink time slot is full, or half of the resources are occupied in each time slot;

There are 8 frequency divisions in the frequency domain, and 4 to 8 different sets of PRACH resources in the frequency domain are obtained according to msg1-FrequencyStart.

In implementation, the reserved modules are further used for:

Group the PRACH resources;

Each terminal is assigned to a different PRACH resource group.

In implementation, the FDM of each PRACH resource group is 8, and each resource block contains 40 to 50 non-contention resolution sequences.

For the convenience of description, each part of the above-described device is divided into various modules or units by function and described separately. Of course, when implementing the present invention, the functions of each module or unit can be implemented in the same or multiple software or hardware.

Figure 6 is a schematic diagram of the terminal structure. As shown in the figure, the terminal includes:

The processor 600 is used to read the program in the memory 620 and perform the following processes:

Determine the PRACH resources that can initiate random access, where the PRACH resources include: RACH-ConfigCommon resources obtained by the terminal by monitoring the cell MIB, and/or RACH-ConfigDedicated resources determined by the terminal through RRC reconfiguration;

Initiate random access on the RACH-ConfigDedicated resource, and initiate competition random access on the RACH-ConfigCommon resource after being dropped;

Transceiver 610 for receiving and transmitting data under the control of processor 600.

In implementation, random access is initiated on the RACH-ConfigDedicated resource in one of the following ways or a combination thereof:

When the usage period of the PRACH resource is configured to be infinite, access is performed through RRC reconnection after access failure;

When the terminal is configured with multiple sets of PRACH resources, after access to one set of PRACH resources fails, random access is initiated on the next set of PRACH resources;

When the PRACH resource is configured with a usage time and a release time, access is performed through RRC reconnection after access failure.

In implementation, when it is determined that x in n _SFN mod x=y is set to a maximum value, it is determined that the usage period of the PRACH resource is configured to be infinite.

During implementation, it is determined based on the ra-OccasionList configured by RRC that the terminal is configured with multiple sets of PRACH resources;

When random access is initiated for each set of PRACH resources, random access is initiated according to y in n _SFN mod x=y of each set.

During the implementation, when it is determined that the RACH-Config Generic in IE RACH-ConfigDedicated contains msg1-duration that configures the usage time and release time of PRACH, it is determined that the PRACH resource is configured with usage time and release time, where msg1-duration is this The usage time of MSG1 and the starting time point of msg1-duration are the time points when the terminal sends MSG for the first time. After the usage time of MSG1 is exceeded, the PRACH corresponding to msg1-duration is released.

Implementation further includes:

msg1 is sent in the same sequence at each burst position of the subframe.

In FIG. 6 , the bus architecture may include any number of interconnected buses and bridges, specifically one or more processors represented by processor 600 and various circuits of the memory represented by memory 620 are linked together. The bus architecture can also link together various other circuits such as peripherals, voltage regulators, and power management circuits, which are all well known in the art and therefore will not be described further herein. The bus interface provides the interface. Transceiver 610 may be a plurality of elements, including a transmitter and a receiver, providing a unit for communicating with various other devices over a transmission medium. For different user equipment, the user interface 630 can also be an interface capable of externally connecting internal and external required equipment. The connected equipment includes but is not limited to a keypad, a display, a speaker, a microphone, a joystick, etc.

The processor 600 is responsible for managing the bus architecture and general processing, and the memory 620 can store data used by the processor 600 when performing operations.

An embodiment of the present invention provides a terminal, including:

Resource determination module, used to determine PRACH resources that can initiate random access, wherein the PRACH resources include: RACH-ConfigCommon resources obtained by the terminal by monitoring the cell MIB, and/or RACH-ConfigDedicated determined by the terminal through RRC reconfiguration resource;

An access module, configured to initiate random access on the RACH-ConfigDedicated resource, and initiate competition random access on the RACH-ConfigCommon resource after being disconnected.

In implementation, the access module is further configured to initiate random access on the RACH-ConfigDedicated resource in one of the following ways or a combination thereof:

When the usage period of the PRACH resource is configured to be infinite, access is performed through RRC reconnection after access failure;

When the terminal is configured with multiple sets of PRACH resources, after access to one set of PRACH resources fails, random access is initiated on the next set of PRACH resources;

When the PRACH resource is configured with a usage time and a release time, access is performed through RRC reconnection after access failure.

In implementation, the resource determination module is further configured to determine that the usage period of the PRACH resource is configured to be infinite when it is determined that x in n _SFN mod x=y is set to a maximum value.

During implementation, the resource determination module is further used to determine whether the terminal is configured with multiple sets of PRACH resources based on the ra-OccasionList configured by the RRC;

The access module is further configured to initiate random access according to y in n _SFN mod x=y of each set of PRACH resources when random access is initiated.

During implementation, the resource determination module is further used to determine that the PRACH resource configuration has a usage time and a release time when it is determined that the msg1-duration of the RACH-Config Generic in the IE RACH-ConfigDedicated contains the usage time and release time of the PRACH, where , msg1-duration is the usage time of MSG1. The starting time point of msg1-duration is the time point when the terminal sends MSG for the first time. After the usage time of MSG1 is exceeded, the PRACH corresponding to msg1-duration is released.

In the implementation, the access module is further used to use msg1 sent in the same sequence at each burst position of the subframe.

For the convenience of description, each part of the above-described device is divided into various modules or units by function and described separately. Of course, when implementing the present invention, the functions of each module or unit can be implemented in the same or multiple software or hardware.

An embodiment of the present invention provides a computer-readable storage medium, which stores a computer program for executing the above-mentioned PRACH resource configuration method and/or random access method.

For specific implementation, please refer to the implementation of the PRACH resource configuration method and/or the random access method.

To sum up, in the technical solution provided by the embodiment of the present invention, RACH-ConfigDedicated and RACH-ConfigCommon configure different resources to reduce the RACH-ConfigDedicated uplink resource overhead at high-capacity times.

The base station and terminal can support multiple sets of RACH-ConfigDedicated resource configurations for handover, using the RRC message ra-OccasionList configuration.

Configure the new PRACH time domain period to be aperiodic, configure the SFN's x to a maximum value, and support configuring multiple sets of PRACH resources for the terminal, so that when one PRACH access fails, it can re-access on other PRACH resources.

Configure the RACH-ConfigDedicated effective time, configure MSG1-duration in the RRC reconfiguration message, and maintain the effective time of MSG1 during handover. When the time expires, the base station releases the PRACH resources used for handover for subsequent uplink resource transmission.

The base station reserves multiple sets of PRACH resources and groups different PRACH resources for the terminals according to the terminal's measurement and reporting time to ensure staggered access of the terminals, improve the access success rate and reduce the access waiting delay. The staggering process can use the first-in-first-out method to allocate PRACH resources, or the average grouping method to allocate PRACH resources.

MSG1-FDM is configured with a maximum number of 8, which increases PRACH resources in the same subframe and reduces PRACH access delay.

It can be seen that due to the characteristic of several terminals switching at the same time, represented by high-speed rail scenarios, by dynamically adjusting the PRACH resource configuration during handover and statically configuring the access resource configuration during non-access, and increasing the number of PRACH resources during handover, it is guaranteed Large-capacity terminals can quickly switch during high-speed rail switching, improving user performance and experience.

Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Thus, the invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the invention may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, magnetic disk storage, optical storage, etc.) embodying computer-usable program code therein.

The invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each process and/or block in the flowchart illustrations and/or block diagrams, and combinations of processes and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing device to produce a machine, such that the instructions executed by the processor of the computer or other programmable data processing device produce a use A device for realizing the functions specified in one process or multiple processes of the flowchart and/or one block or multiple blocks of the block diagram.

These computer program instructions may also be stored in a computer-readable memory that causes a computer or other programmable data processing apparatus to operate in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including the instruction means, the instructions The device implements the functions specified in a process or processes of the flowchart and/or a block or blocks of the block diagram.

These computer program instructions may also be loaded onto a computer or other programmable data processing device, causing a series of operating steps to be performed on the computer or other programmable device to produce computer-implemented processing, thereby executing on the computer or other programmable device. Instructions provide steps for implementing the functions specified in a process or processes of a flowchart diagram and/or a block or blocks of a block diagram.

Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the invention. In this way, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and equivalent technologies, the present invention is also intended to include these modifications and variations.

Claims (18)

1. A physical random access channel PRACH resource configuration method, characterized by including: The base station determines the number of terminals that need to be switched and the switching time; When the number of terminals and handover time exceed the preset threshold, large-bandwidth uplink resources and/or short-period uplink resources are reserved as PRACH resources for terminals to initiate random access; After the handover is completed, release the reserved PRACH resources; The PRACH resources include: The terminal obtains the physical random access channel common configuration RACH-ConfigCommon resources by monitoring the cell control information block MIB, and/or specifies the physical random access channel dedicated configuration RACH-ConfigDedicated resources through RRC reconfiguration; The RACH-ConfigCommon resource in the PRACH resource is used for contention random access after the terminal is disconnected; After receiving msg1 sent by the terminal in the same sequence at each burst position of the subframe, diversity gain is performed; Group the PRACH resources; Each terminal is assigned to a different PRACH resource group. 2. The method of claim 1, wherein the number of terminals that need to be switched and the switching time are determined based on the time and number of measurement reports MR sent by each terminal. 3. The method of claim 1, further comprising configuring RACH-ConfigDedicated resources in the PRACH resources in one of the following ways or a combination thereof: Configure the usage period of PRACH resources to be infinite; Configure multiple sets of PRACH resources for each terminal; Configure the usage time and release time of PRACH resources. 4. The method of claim 3, wherein configuring the usage period of the PRACH resource to be infinite is to set x in ⁿ _SFN modx=y to a maximum value. 5. The method of claim 3, wherein configuring multiple sets of PRACH resources for each terminal is to configure multiple sets of physical random access channel configuration index prach-Configuration Index for the terminal, and ⁿ _SFN modx of each set =Y in y is set to different values, and multiple sets of PRACH resources are configured through the radio resource control RRC to configure the random access opportunity list ra-OccasionList. 6. The method of claim 3, wherein configuring the usage time and release time of PRACH resources is to add msg1- in the physical random access channel configuration generic RACH-ConfigGeneric in the information unit IE RACH-ConfigDedicated. duration is used to configure the usage time and release time of PRACH. Among them, msg1-duration is the usage time of MSG1. The starting time point of msg1-duration is the time point when the terminal sends MSG for the first time. After the usage time of MSG1 is exceeded, Release the PRACH corresponding to msg1-duration. 7. The method of claim 1, wherein the time-frequency domain resource of the PRACH resource is: The time domain of the uplink time slot is full, or half of the resources are occupied in each time slot; There are 8 frequency divisions in the frequency domain, and 4 to 8 different sets of PRACH resources in the frequency domain are obtained according to the message 1-start frequency msg1-FrequencyStart. 8. The method of claim 1, wherein the frequency division multiplexing FDM of each PRACH resource group is 8, and each resource block contains 40 to 50 non-contention resolution sequences. 9. A random access method, characterized by including: The terminal determines the PRACH resources that can initiate random access, where the PRACH resources include: RACH-ConfigCommon resources obtained by the terminal by monitoring the cell MIB, and/or RACH-ConfigDedicated resources determined by the terminal through RRC reconfiguration; The terminal initiates random access on the RACH-ConfigDedicated resource, and after being disconnected, initiates competition random access on the RACH-ConfigCommon resource; The terminal uses msg1 sent in the same sequence at each burst position of the subframe; Wherein, the PRACH resources are grouped; each terminal is assigned to a different PRACH resource group. 10. The method of claim 9, wherein the terminal initiates random access on the RACH-ConfigDedicated resource in one of the following ways or a combination thereof: When the usage period of the PRACH resource is configured to be infinite, access is performed through RRC reconnection after access failure; When the terminal is configured with multiple sets of PRACH resources, after access to one set of PRACH resources fails, random access is initiated on the next set of PRACH resources; When the PRACH resource is configured with a usage time and a release time, access is performed through RRC reconnection after access failure. 11. The method of claim 10, wherein the terminal determines that the usage period of the PRACH resource is configured to be infinite when it determines that x in ⁿ _SFN modx=y is set to a maximum value. 12. The method of claim 10, wherein the terminal determines that the terminal is configured with multiple sets of PRACH resources according to the ra-OccasionList configured by RRC; When the terminal initiates random access in each set of PRACH resources, it initiates random access according to y in ⁿ _SFN modx=y of each set. 13. The method of claim 10, wherein when the terminal determines that there is a message 1 period msg1-duration configuring the usage time and release time of PRACH in the RACH-Config Generic in IE RACH-ConfigDedicated, determine PRACH The resource configuration has usage time and release time. Among them, msg1-duration is the usage time of message 1MSG1. The starting time point of msg1-duration is the time point when the terminal sends MSG for the first time. After the usage time of MSG1 is exceeded, msg1 is released. -The PRACH corresponding to duration. 14. A base station, characterized in that it includes: Processor, used to read the program in the memory and perform the following processes: Determine the number of terminals that need to be switched and the switching time; When the number of terminals and handover time exceed the preset threshold, large-bandwidth uplink resources and/or short-period uplink resources are reserved as PRACH resources for terminals to initiate random access; After the handover is completed, release the reserved PRACH resources; a transceiver for receiving and transmitting data under the control of the processor; The PRACH resources include: The terminal obtains the physical random access channel common configuration RACH-ConfigCommon resources by monitoring the cell control information block MIB, and/or specifies the physical random access channel dedicated configuration RACH-ConfigDedicated resources through RRC reconfiguration; The RACH-ConfigCommon resource in the PRACH resource is used for contention random access after the terminal is disconnected; After receiving msg1 sent by the terminal in the same sequence at each burst position of the subframe, diversity gain is performed; Group the PRACH resources; Each terminal is assigned to a different PRACH resource group. 15. A base station, characterized in that it includes: Determination module, used to determine the number of terminals that need to be switched and the switching time; The reservation module is used to reserve large-bandwidth uplink resources and/or short-period uplink resources as PRACH resources for terminals to initiate random access when the number of terminals and handover time exceed the preset threshold; A release module, configured to release the reserved PRACH resources after the handover is completed; The PRACH resources include: The terminal obtains the physical random access channel common configuration RACH-ConfigCommon resources by monitoring the cell control information block MIB, and/or specifies the physical random access channel dedicated configuration RACH-ConfigDedicated resources through RRC reconfiguration; The RACH-ConfigCommon resource in the PRACH resource is used for contention random access after the terminal is disconnected; The release module is further configured to perform diversity gain after receiving msg1 sent by the terminal in the same sequence at each burst position of the subframe; The reservation module is further configured to: group the PRACH resources; and allocate each terminal to a different PRACH resource group. 16. A terminal, characterized in that it includes: Processor, used to read the program in the memory and perform the following processes: Determine the PRACH resources that can initiate random access, where the PRACH resources include: RACH-ConfigCommon resources obtained by the terminal by monitoring the cell MIB, and/or RACH-ConfigDedicated resources determined by the terminal through RRC reconfiguration; Initiate random access on the RACH-ConfigDedicated resource, and initiate competition random access on the RACH-ConfigCommon resource after being dropped; a transceiver for receiving and transmitting data under the control of the processor; The terminal uses msg1 sent in the same sequence at each burst position of the subframe; Wherein, the PRACH resources are grouped; each terminal is assigned to a different PRACH resource group. 17. A terminal, characterized in that it includes: Resource determination module, used to determine PRACH resources that can initiate random access, wherein the PRACH resources include: RACH-ConfigCommon resources obtained by the terminal by monitoring the cell MIB, and/or RACH-ConfigDedicated determined by the terminal through RRC reconfiguration resource; An access module, configured to initiate random access on the RACH-ConfigDedicated resource, and initiate competition random access on the RACH-ConfigCommon resource after being disconnected; The access module is further used by the terminal to send msg1 in the same sequence at each burst position of the subframe; Wherein, the PRACH resources are grouped; each terminal is assigned to a different PRACH resource group. 18. A computer-readable storage medium, characterized in that the computer-readable storage medium stores a computer program for executing the method according to any one of claims 1 to 13.