CN107147475B

CN107147475B - Modulation coding mode adjusting method and base station

Info

Publication number: CN107147475B
Application number: CN201710510407.2A
Authority: CN
Inventors: 刘震; 廖礼宇
Original assignee: Comba Telecom Systems China Ltd
Current assignee: Comba Network Systems Co Ltd
Priority date: 2017-06-28
Filing date: 2017-06-28
Publication date: 2020-04-14
Anticipated expiration: 2037-06-28
Also published as: WO2019000873A1; CN107147475A

Abstract

The invention discloses a modulation coding mode adjusting method and a base station, which achieve the beneficial effect of saving transmission resources. The method for adjusting the modulation coding mode comprises the following steps: the base station allocates bandwidth for at least one group call service according to the order of the adopted preset modulation coding scheme MCS; the terminals covered by the base station are divided into a plurality of groups, each group comprises a plurality of terminals, and the group calling service is a service in which any one terminal and other terminals in any one group simultaneously carry out calling; and if the bandwidth allocated to the at least one group call service is larger than a first preset bandwidth, the base station increases the order of the MCS adopted by the at least one group call service.

Description

Modulation coding mode adjusting method and base station

Technical Field

The present invention relates to the field of communications technologies, and in particular, to a method for adjusting a modulation and coding scheme and a base station.

Background

In some industries, at the same time, one user needs to know the working conditions of other users, so as to schedule the work of other users. For example, in the custody security industry, a supervisor needs to know the work situation of the workers he or she leads to schedule the work of those workers. For this reason, the current system can provide a group call service. The group call service is a service that occurs in a group consisting of a plurality of terminals, in which only one terminal actively initiates a call and the remaining terminals are called parties. For example, the group call service may be a call occurring in a group consisting of a plurality of terminals, during the call, one terminal may actively initiate a call to all other terminals in the group, and when a user of the terminal initiating the call speaks, users of other terminals in the group may listen to the call at the same time. Therefore, a user in a group can know the conditions of other users in the group, and the work of other users can be conveniently scheduled.

Generally, terminals may be divided into a plurality of groups in advance according to services performed by the terminals. For example, terminal a, terminal B, terminal C, terminal D, terminal E, and terminal F, where the service performed by terminal a, terminal B, and terminal C is a security service, terminal a, terminal B, and terminal C may be divided into one group. The service performed among the terminal D, the terminal E, and the terminal F is a railway logistics service, and then the terminal D, the terminal E, and the terminal F may be divided into one group. After the terminals are grouped, the group where the terminals are located can request to access the base station, and the base station can know the number of the group where the terminals are located in advance, so that calls can be initiated to different groups according to the numbers of the different groups.

When any group covered by the base station needs to perform the group call service, the base station allocates bandwidth for the group call service to transmit group call service data. In a Long Term Evolution (LTE) system, a channel provided by the system may be shared by all terminals in the system. The base station may use multiple Modulation and Coding Schemes (MCS) when transmitting the group call service data, such as a Quadrature Phase Shift Keying (QPSK) Scheme, a 16 Quadrature Amplitude Modulation (16 QAM) Scheme, or a 64QAM Scheme. Different MCS correspond to different index values, and when the base station selects the MCS, the index value is selected, namely the corresponding MCS is selected. For example, if the index value of the MCS is 1, the corresponding MCS is the QPSK scheme, and if the index value of the MCS is 3, the corresponding MCS is the 16QAM scheme. The index value of the MCS is also referred to as the order of the MCS.

In general, the base station determines how to configure the order of the MCS according to a Channel Quality Indicator (CQI) fed back by the terminal. For a terminal in Radio resource control protocol connection (RRC connection), CQI may be transmitted to a base station, so that the base station may determine an order of the configured MCS according to the CQI fed back by the terminal in RRC connection. In the LTE system, most terminals in a group are in an Idle (Idle) state, and the terminals in the Idle state cannot feed back CQI to the base station, so the base station configures an order of MCS in advance for all groups covered by the base station. The larger the order of the MCS is, the larger the transmission rate of the data is, that is, the more data needs to be transmitted in the same time period, and in a limited bandwidth, a large amount of data is likely to cause congestion. Therefore, in order to ensure reliability of data transmission, the base station configures an initial MCS for all groups, and configures a smaller-order MCS for all groups in advance.

However, the smaller the order of the MCS, the smaller the amount of data that can be carried per Resource Block (RB) allocated by the base station when allocating bandwidth to the call service to be performed per group according to the MCS. Therefore, when the base station allocates bandwidth for the call service to be performed in each group under the condition of adopting a smaller MCS order, more RBs need to be allocated, resulting in waste of transmission resources.

Disclosure of Invention

The embodiment of the invention provides a modulation and coding mode adjusting method and a base station, which achieve the beneficial effect of saving transmission resources.

In a first aspect, an embodiment of the present invention provides a method for adjusting a modulation and coding scheme, where the method includes:

the base station allocates bandwidth for at least one group call service according to the order of the adopted preset modulation coding scheme MCS; the terminals covered by the base station are divided into a plurality of groups, each group comprises a plurality of terminals, and the group calling service is a service in which any one terminal and other terminals in any one group simultaneously carry out calling;

and if the bandwidth allocated to the at least one group call service is larger than a first preset bandwidth, the base station increases the order of the MCS adopted by the at least one group call service.

Optionally, the increasing, by the base station, the order of the MCS used for the at least one group call service includes:

the base station selects M group calling services of which the value of the downlink channel quality indication CQI of the group is larger than a first threshold from the at least one group calling service; the CQI value of one group is the average value of the CQI values reported by a plurality of terminals included in the group, and M is a positive integer;

and the base station increases the orders of M MCSs respectively adopted by the M group call services.

Optionally, the method further includes:

if the bandwidth allocated to the at least one group call service is less than or equal to the first preset bandwidth, the base station judges whether the bandwidth allocated to the at least one group call service is less than a second preset bandwidth; wherein the second preset bandwidth is smaller than the first preset bandwidth;

and if the bandwidth allocated to the at least one group call service is smaller than the second preset bandwidth, the base station reduces the order of the MCS adopted by the at least one group call service.

Optionally, the reducing, by the base station, the order of the MCS used for the at least one group call service includes:

the base station selects N group calling services of which the value of the downlink channel quality indicator CQI of the group is smaller than a second threshold from the at least one group calling service; the CQI value of one group is the average value of CQI values reported by a plurality of terminals included in the group, and N is a positive integer;

and the base station reduces the orders of N MCS respectively adopted by the N group call services.

Optionally, an average value of CQI values reported by a plurality of terminals included in the group is:

and the average value of the CQI value reported by the terminal in the RRC CONNECT state of the radio resource control protocol and the CQI value reported by the terminal in the IDLE RRC IDLE state of the radio resource control protocol in the group.

In a second aspect, an embodiment of the present invention provides a base station, including:

the distribution module is used for distributing bandwidth for at least one group call service according to the order of the adopted preset modulation coding scheme MCS; the terminals covered by the base station are divided into a plurality of groups, each group comprises a plurality of terminals, and the group calling service is a service in which any one terminal and other terminals in any one group simultaneously carry out calling;

and the adjusting module is used for increasing the order of the MCS adopted by the at least one group calling service by the base station if the bandwidth allocated to the at least one group calling service is greater than a first preset bandwidth.

Optionally, the adjusting module increases the order of the MCS used for the at least one group call service, including:

the adjusting module selects M group calling services of which the value of the downlink Channel Quality Indicator (CQI) of the group is larger than a first threshold from the at least one group calling service; the CQI value of one group is the average value of the CQI values reported by a plurality of terminals included in the group, and M is a positive integer;

the adjusting module increases the orders of M MCSs respectively adopted by the M group call services.

Optionally, the adjusting module is further configured to:

if the bandwidth allocated to the at least one group call service is less than or equal to the first preset bandwidth, the adjusting module judges whether the bandwidth allocated to the at least one group call service is less than a second preset bandwidth; wherein the second preset bandwidth is smaller than the first preset bandwidth;

if the bandwidth allocated to the at least one group call service is smaller than the second preset bandwidth, the adjusting module reduces the order of the MCS adopted by the at least one group call service.

Optionally, the reducing, by the adjusting module, the order of the MCS used for the at least one group call service includes:

the adjusting module selects N group calling services of which the value of the downlink channel quality indicator CQI of the group is smaller than a second threshold from the at least one group calling service; the CQI value of one group is the average value of CQI values reported by a plurality of terminals included in the group, and N is a positive integer;

the adjusting module reduces the orders of N MCS respectively adopted by the N group call services.

In the embodiment of the invention, the base station adjusts the order of the MCS according to the order of the preset MCS for the size of the bandwidth allocated to the at least one group calling service, if the bandwidth allocated to the at least one group calling service is larger than the first preset bandwidth, the bandwidth allocated to the at least one group calling service by the base station is larger and may be close to the maximum bandwidth supported by the base station, and at the moment, the order of the MCS can be increased by the base station, so that the bandwidth is reallocated to the at least one group calling service according to the order of the increased MCS, so that the amount of data carried by one allocated RB is larger, the number of RBs to be allocated is smaller, and transmission resources are saved.

Drawings

Fig. 1 is an architecture diagram of a trunking communication system according to an embodiment of the present invention;

fig. 2 is a flowchart of a method for adjusting a modulation and coding scheme according to an embodiment of the present invention;

fig. 3 is a schematic diagram illustrating that the system capacity is limited due to the modulation and coding scheme adjustment method in the prior art;

fig. 4 is a schematic diagram of a solution to the capacity limitation of the system according to an embodiment of the present invention;

fig. 5 is a schematic diagram of a solution to the capacity limitation of the system according to an embodiment of the present invention;

fig. 6 is a schematic structural diagram of a base station according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more clearly and completely understood, the technical solutions in the embodiments of the present invention will be described below with reference to the accompanying drawings in the embodiments of the present invention.

First, an application scenario of the embodiment of the present invention is described.

Referring to fig. 1, fig. 1 is a block diagram of a communication system. Fig. 1 includes a base station 101 and a plurality of terminals 102. The base station 101 may be an Evolved Node B (eNB) or e-NodeB, and the terminal 102 is a terminal used by a user, such as a walkie-talkie. One may divide the plurality of terminals 102 into a plurality of groups in advance according to the traffic performed between the plurality of terminals 102, and each group may include a plurality of terminals 102. After the plurality of terminals 102 are divided into a plurality of groups, the group in which the terminal 102 is located may request to access the base station, and the base station may know the number of the group in which the terminal 102 is located in advance, so that a call may be initiated to different groups according to the numbers of the different groups. For example, the service performed between 3 terminals 102 is security and management service, the 3 terminals are divided into one group, the service performed between 4 terminals 102 is railway logistics service, and the 4 terminals are divided into one group. Fig. 1 illustrates an example in which 10 terminals 102 covered by a base station 101 are divided into 3 groups, i.e., group 1, group 2, and group 3.

Any one terminal 102 may actively initiate a call to other terminals 102 in any one group, the other terminals 102 in the group being called parties. Any terminal 102 that initiates a call may or may not be in the same group as the called terminal 102. Fig. 1 illustrates that any terminal 102 that is actively initiating a call is in the same group as the called terminal 102. While the user speaks through the terminal 102 that is actively initiating the call, the users in the group using the other terminals 102 may listen simultaneously. When a group call service is performed, the terminal 102 which is actively initiating a call sends data to the base station 101, and the base station 101 sends the received data to other terminals 102 participating in the group call service.

Based on the problem of resource waste in the group call service in the prior art, embodiments of the present invention provide a method and a base station for adjusting a modulation and coding scheme, where after a base station 101 allocates a bandwidth to at least one group call service according to a preset MCS order, the MCS order may be adjusted according to the size of the bandwidth allocated to the at least one group call service, and if the bandwidth allocated to the at least one group call service is wider, for example, close to a maximum bandwidth supported by the base station 101, the base station 101 may increase the MCS order. The base station 101 reallocates the bandwidth for at least one group call service according to the increased MCS order, the allocated RB can carry a large amount of data, and the number of RBs to be allocated is small, thereby saving transmission resources and improving the capacity of the system.

The technical scheme provided by the embodiment of the invention is described in the following with the accompanying drawings of the specification.

An embodiment of a modulation and coding scheme adjustment method according to the present invention is described in detail with reference to the communication system architecture diagram shown in fig. 1, and the embodiment is illustrated in fig. 1, and is not limited to use only in the system architecture shown in fig. 1. The adjusting method can be executed by the base station 101, please refer to fig. 2, and the flow of the adjusting method is described as follows:

s201: the base station 101 allocates bandwidth to at least one group call service according to the order of the adopted preset MCS, wherein the terminals 102 covered by the base station 101 are divided into a plurality of groups, each group comprises a plurality of terminals 102, and the group call service is a service in which any one terminal 102 and other terminals 102 in any one group perform calling simultaneously;

s202: if the bandwidth allocated to the at least one group call service is greater than the first preset bandwidth, the base station 101 increases the order of the MCS used for the at least one group call service.

The base station 101 covers a plurality of groups, and for any group covered by the base station 101, when there is a group call service, the base station 101 allocates a bandwidth for the group call service, and if there is no group call service, the base station 101 does not need to allocate a bandwidth for the group call service. When a group has a group call service, the group sends a request message to the base station 101, where the request message is used to request the base station 101 to allocate bandwidth for the group call service to be performed by the group, and the base station 101 receives the request message sent by the group and allocates bandwidth for the corresponding group call service. The base station 101 allocates bandwidth for each group transmitting the request message according to the order of the adopted MCS, that is, allocates bandwidth for the group call service to be performed by each group transmitting the request message. Generally, the base station 101 configures the order of the MCS in advance, so the base station 101 may directly allocate a bandwidth to the group call service to be performed by each group transmitting the request message according to the order of the MCS configured in advance.

The base station 101 allocates bandwidth for a group call service according to the order of the preconfigured MCS, which may be implemented by allocating RBs, for example, the order of the MCS is 6, the bandwidth of one RB is 180kHz, the bandwidth required by the group call service performed by one group is 900kHz, and the base station 101 needs to allocate 5 RBs for the group service. Of course, the base station 101 may also allocate a bandwidth for one group by allocating Resource Elements (REs), or allocate a bandwidth for one group by allocating Scheduling Blocks (SBs), and the embodiment of the present invention does not limit which way the base station 101 allocates a bandwidth for one group.

In order to ensure the reliability of data transmission, the order of the MCS pre-configured by the base station 101 is generally small. However, when the base station 101 uses the MCS with the smaller order to allocate the bandwidth for the group call service, the amount of data that can be carried by one allocated RB is smaller, so when the base station 101 uses the MCS with the smaller order to allocate the bandwidth for the group call service, more RBs need to be allocated, which results in waste of system resources. At this time, if there is a new terminal 102 to join a certain group, the new terminal 102 may not join the certain group due to insufficient available resources of the base station 101. That is, the number of terminals 102 that the base station 101 can join is limited, so the number of terminals 102 corresponding to the group call service supported by the base station 101 is small, and the capacity of the system is small.

Therefore, in the embodiment of the present invention, after the base station 101 allocates the bandwidth to at least one group call service according to the preset MCS with a smaller order, the order of the MCS may be appropriately adjusted. For example, the base station 101 increases the order of the MCS as much as possible to increase the capacity of the system, or decreases the order of the MCS as much as possible to improve the reliability of data transmission.

Therefore, transmission resources are saved, and the capacity of the system is improved.

In the embodiment of the present invention, after the base station 101 allocates a bandwidth to at least one group call service according to the MCS with the preset order, it may first determine whether the bandwidth allocated to the at least one group call service is greater than a first preset bandwidth, and if the bandwidth allocated to the at least one group call service by the base station 101 is greater than the first preset bandwidth, it may be considered that the bandwidth allocated to the at least one group call service by the base station 101 is close to the maximum bandwidth supported by the base station 101. The first preset bandwidth may be set according to a maximum bandwidth supported by the base station 101, for example, the first preset bandwidth may be 90% or 80% of the maximum bandwidth supported by the base station 101.

If the bandwidth allocated by the base station 101 for at least one group call service is close to the maximum bandwidth supported by the base station 101, the available resources of the system are less. Then, at this time, the base station 101 may increase the order of the MCS used for the at least one group call service, so that the subsequent base station 101 allocates a bandwidth for the at least one group call service according to the increased order of the MCS, the allocated RB has a larger data amount and a smaller number of allocated RBs, thereby saving transmission resources and contributing to increase the capacity of the system.

However, the larger the order of the MCS, the larger the transmission rate of the data, that is, the more data needs to be transmitted in the same time period, and in the limited bandwidth, a large amount of data is easy to cause congestion. That is, the MCS with a larger order can only be applied to the terminal 102 with a better channel quality. In practice, the channel quality of the terminals 102 participating in each group call service is better and worse. If the base station 101 increases the order of the MCS used for all group call services, for a group with poor channel quality, the terminal 102 in the group may not receive the data transmitted by the base station 101 at all, that is, the reliability of data transmission cannot be ensured. Therefore, when increasing the order of the MCS used for the at least one group call service, the base station 101 may select a group call service with a better channel quality in the group from the at least one group call service, and then increase the order of the MCS used for the selected group call service. Thus, for the group with poor channel quality, the order of the MCS is not increased, and the reliability of data transmission can be maintained. For the group with better channel quality, the order of the MCS is increased, the reliability of data transmission is ensured, meanwhile, the transmission resource can be saved, and the capacity of the system is improved.

When the base station 101 selects a group call service with a better channel quality from at least one group call service, the group call services may be sorted according to the descending order of the CQI value of the group corresponding to each group call service, and then the first M group call services are selected, where the CQI values of the groups corresponding to the M selected group call services are all greater than the first threshold value. Where M is a positive integer, the CQI value of a group is an average value of CQI values reported by multiple terminals 102 included in the group, and the first threshold may be a preset value, and if the CQI value of a group is greater than the first threshold, the channel quality of the group may be considered to be better.

Since the value of CQI of one group varies, for example, the value of CQI of a certain group is large at the previous time, but the value of CQI of the group is small at the next time. If the base station 101 increases the order of M MCSs respectively used for M group call services by a large amount at a time, reliability of data transmission cannot be guaranteed for a group having a smaller CQI value next time. Therefore, when the base station 101 increases the order of the MCS used for each of the M group call services, the increased order is small, for example, the order of the MCS may be increased by 1, so that the reliability of data transmission cannot be ensured. After the base station 101 increases the order of the MCS, bandwidth is allocated to at least one group call service according to the increased order of the MCS, and if the bandwidth allocated to the at least one group call service is still greater than the first preset bandwidth, the base station 101 may continue to increase the order of the MCS used for the group call service with better channel quality of the group in which the base station is located, and may still increase the order of the MCS by 1, so as to ensure reliability of data transmission as much as possible and improve capacity of the system.

In the embodiment of the present invention, if the bandwidth allocated to at least one group call service by the base station 101 is less than or equal to the first preset bandwidth, it may further be determined whether the bandwidth allocated to at least one group call service is less than the second preset bandwidth. The second preset bandwidth is smaller than the first preset bandwidth, for example, the second preset bandwidth may be 50% or 40% of a maximum bandwidth supported by the base station 101. If the bandwidth allocated by the base station 101 for at least one group call service is less than the second preset bandwidth, it may be considered that the system has more available resources. In this case, the base station 101 may appropriately reduce the order of the MCS used for at least one group call service, so as to improve the reliability of data transmission as much as possible on the premise that the system has more available resources.

The base station 101 allocates bandwidth to the group call service by using the MCS with the smaller order, the less data amount that can be carried by one allocated RB is, the less data needs to be transmitted in the same time period, and the higher the probability of successful data transmission, so the MCS with the smaller order is more suitable for the terminal 102 with the poorer channel quality. However, for the terminal 102 with better channel quality, it is not necessary to reduce the order of the MCS, otherwise, the rate of data transmission is reduced, and the efficiency of the system is also reduced.

The channel quality of the terminal 102 participating in each group call service is better, or worse, and if the base station 101 reduces the order of the MCS used for all group call services, the data transmission rate will be reduced, and the system efficiency will also be reduced. Therefore, considering that there is a group with better channel quality, when reducing the order of the MCS used for at least one group call service, the base station 101 may first select a group call service with worse channel quality in the group from the at least one group call service, and then reduce the order of the MCS used for the selected group call service. Thus, for the group with poor channel quality, the order of the MCS is reduced, and the reliability of data transmission can be improved.

When the base station 101 selects a group call service with poor channel quality from at least one group call service, the group call services may be sorted according to the descending order of the CQI value of the group corresponding to each group call service, and then the first N group call services are selected, where the CQI values of the groups corresponding to the N selected group call services are all smaller than the second threshold. Where N is a positive integer, the CQI value of a group is an average value of CQI values reported by multiple terminals 102 included in the group, and the second threshold may be a preset value, and if the CQI value of a group is smaller than the second threshold, the channel quality of the group may be considered to be poor.

Since the value of the CQI of the group in which at least one group call service is located is changed, for example, the value of the CQI of a certain group is higher at the previous time, but the value of the CQI of the group is smaller at the next time. If the base station 101 reduces the order of the MCS used for the N group call services by a large amount at a time, it is unnecessary to reduce the rate of data transmission for the group having a higher CQI value at the next time, thereby reducing the efficiency of data transmission by the system. Therefore, when the base station 101 reduces the order of the MCS used for the N group call services, the reduced order is small, for example, the reduced order of the MCS may be 1, so that a large change does not occur, and the efficiency of the system for transmitting data is prevented from being reduced as much as possible. After the base station 101 reduces the order of the MCS, bandwidth is allocated to at least one group call service according to the reduced order of the MCS, and if the bandwidth allocated to the at least one group call service is still smaller than a second preset bandwidth, the base station 101 may continue to reduce the order of the MCS used for the group call service with poor channel quality of the group in which the base station is located, and may still reduce the order of the MCS by 1, so as to improve reliability of data transmission as much as possible while the system capacity is large.

In this embodiment of the present invention, the average value of the CQI values reported by the multiple terminals 102 included in a group may specifically be an average value of the CQI values reported by the terminals 102 in a Radio Resource Control protocol connection (RRC connection) state and the CQI values reported by the terminals 102 in a Radio Resource Control protocol Idle (RRC Idle) state in a group.

In the LTE system, all terminals share a downlink channel, and generally, among a plurality of terminals 102 included in one group, some terminals 102 are in an RRC connection state, and some terminals 102 are in an RRC IDLE state, while the base station 101 formulates a corresponding CQI feedback mechanism for the terminals 102 in the RRC connection state, and the base station 101 allocates a bandwidth of a group in which the group call service is located according to a value of a CQI fed back by the terminals 102 in the RRCCONNECT state. However, if the channel quality of the terminal 102 in the RRCIDLE state is good, the base station 101 allocates the bandwidth of the group in which the group call service is located only according to the CQI value fed back by the terminal 102 in the RRC connection state, and obviously, the accuracy is low.

Therefore, in the embodiment of the present invention, the average value of the CQI values reported by the multiple terminals 102 in a group includes both the CQI value reported by the terminal 102 in the RRC connection state in the group and the average value of the CQI value reported by the terminal 102 in the RRC IDLE state, that is, the bandwidth is allocated to at least one group call service according to the CQI values of all the terminals 102 in the group while considering the channel quality of all the terminals 102 in the group, so as to improve the accuracy of allocating the bandwidth as much as possible.

In a possible embodiment, the manner of reporting the CQI value by the terminal 102 in the RRC IDLE state may be implemented as follows. The base station 101 may send a measurement instruction to the terminal 102 in the RRC IDLE state, and the measurement instruction may request the terminal 102 in the RRC IDLE state to measure the quality of the downlink channel. After measurement, the terminal 102 in the RRC IDLE state transmits the CQI value to the base station 101. In order to reduce the burden on the base station 101, if the value of the CQI measured by the terminal 102 in the RRC IDLE state is greater than a third threshold value, where the third threshold value is used to indicate that the channel quality of the group in which the terminal 102 is located is good, the terminal 102 in the RRC IDLE state does not transmit the measured value of the CQI to the base station 101, and at this time, the base station 101 may default the value of the CQI of the terminal 102 in the RRC IDLE state to be the third threshold value.

For better understanding, a method for the base station 101 to adjust the order of the MCS is described below by taking as an example that the order of the MCS previously set by the base station 101 is 6.

The base station 101 configures an order of the initial MCS, for example, the order of the MCS is 6. The base station 101 allocates bandwidth to the group call service according to the MCS with the order of 6. The base station 101 may determine the number of RBs to be allocated for the group call service according to the current MCS value and the size of an RB currently to be transmitted for the group call service. Specifically, the base station 101 may determine the number of RBs to be allocated for the group call service by looking up Table 7.1.7.2.1-1 in 3GPP TS 36.213. For example, the size of one RB currently needing to transmit the group call service is 1128 bits, the order of the MCS is 6, and the base station 101 needs to allocate at least 11 RB resources to the group call service.

Referring to fig. 3, fig. 3 is a schematic diagram illustrating that the MCS adjustment method in the prior art results in limited system capacity. As shown in fig. 3, the base station 101 has scheduled 4 groups of group call services at a subframe Number of 0 where the current System Frame Number (SFN) is n: as the group call service increases, for example, the group 40 also establishes a request with the base station 101, and is also allocated to the position with the subframe number of 0 for scheduling, according to the prior art method, if the group 0 to the group 3 and the group 40 all correspond to a smaller order of MCS, for example, 6, the total number of RBs required by the group 0 to the group 3 and the group 40 easily exceeds the maximum number of RBs corresponding to the maximum bandwidth supported by the base station 101. When this occurs, the prior art can only place part of the group call service, for example, group 40, into the next frame for scheduling, for example, scheduling at SFN n +1 subframe number 1. Therefore, the scheduling delay is increased, especially under the condition that the number of the group calling services is increased, the scheduling delay of the group calling services is greatly increased, and finally the capacity of the system is limited.

Referring to fig. 4, fig. 4 is a schematic diagram of solving the problem of system capacity limitation according to an embodiment of the present invention. As shown in fig. 4, when the base station 101 detects that the total RB requirement of at least one group call service is greater than the preset threshold at the position where the subframe number of the SFN ═ n +1 is 0, the groups 0 to 3 are sorted from large to small according to the average value of the CQI values reported by the multiple terminals 102 included in the group. If the maximum bandwidth supported by the base station 101 is 20MHz, the preset threshold may be 100. The base station 101 may select the first 3 group call services in the ordered group 0 to group 3, for example, group 0 to group 2, and add 1 to the order of the MCS used by the 3 group call services, that is, 7. Since the order of the MCS of the group 0 to the group 2 is increased to 7, the amount of data carried by one RB is increased, and the number of RBs allocated by the base station 101 to the group 0 to the group 2 is small, so that redundant RB resources can be reserved for the group 40 to use, and finally, it is ensured that the total number of RBs required by the group 0 to the group 3 and the group 40 is not greater than a preset threshold, for example, 100 RBs. Compared with the method shown in fig. 3, the group 40 is not placed into the next frame for scheduling, the scheduling delay is not affected, and the group calling capacity is ensured.

Referring to fig. 5, fig. 5 is a schematic diagram of solving the problem of system capacity limitation according to an embodiment of the present invention. As shown in fig. 5, the base station 101 has an order of 15 for the MCS used for group 0 to group 3 at SFN _ n with subframe number 0. Group calling service group 2 and group 3 have performed service release at SFN ═ n, and base station 101 has performed the last scheduling transmission to group 2 and group 3 at SFN ═ n where the subframe number is 0. The base station 101 detects the RB requirement number of the remaining group call at the sub-frame number of SFN ═ n +1 of 0, that is, the total number of RB requirements of group 0 and group 1 is smaller than a preset threshold, for example, the maximum bandwidth supported by the base station 101 is 20MHz, and then the preset threshold may be 50. The group 0 to the group 3 are sorted from small to large according to the average value of the CQI values reported by the plurality of terminals 102 included in the group. The base station 101 may select the first 2 group call services in the ordered group 0 to group 3, for example, the selected first 2 group call services are group 0 to group 1, and reduce the order of the MCS used for the 2 group call services, for example, 14. If the base station 101 determines that the total number of RB requirements required for group 0 to group 1 is still less than 50 at this time, the order of the MCS continues to be decreased by 1 until the total number of RB requirements for group 0 and group 1 is not less than 50, for example, the order of the MCS finally configured by the base station 101 is 7. It can be seen that when the number of group call services decreases, the base station 101 may satisfy that all terminals in the group can reliably receive the data sent by the base station 101 as much as possible by appropriately decreasing the order of the MCS.

The following describes the apparatus provided by the embodiment of the present invention with reference to the drawings.

Referring to fig. 6, based on the same inventive concept, an embodiment of the present invention provides a base station 101, where the base station 101 may include an allocating module 601 and an adjusting module 602. The allocating module 601 may be configured to allocate a bandwidth to at least one group call service according to an order of a preset modulation and coding scheme MCS, where terminals covered by the base station 101 are divided into multiple groups, each group includes multiple terminals 102, and the group call service is a service in which any one terminal 102 and other terminals 102 in any one group perform a call simultaneously. The adjusting module 602 may be configured to increase, by the base station 101, the order of the MCS used for the at least one group call service if the bandwidth allocated to the at least one group call service is greater than the first preset bandwidth.

Optionally, the adjusting module 602 increases the order of the MCS used for the at least one group call service, including:

the adjusting module 602 selects M group call services in which the value of the downlink channel quality indicator CQI of a group is greater than a first threshold from at least one group call service, where the value of the CQI of a group is an average value of the values of CQIs reported by a plurality of terminals 102 included in a group, and M is a positive integer;

the adjusting module 602 increases the order of the M MCSs respectively adopted for the M group call services.

Optionally, the adjusting module 602 is further configured to:

if the bandwidth allocated to at least one group call service is less than or equal to the first preset bandwidth, the adjusting module 602 determines whether the bandwidth allocated to at least one group call service is less than a second preset bandwidth; the second preset bandwidth is smaller than the first preset bandwidth;

if the bandwidth allocated to the at least one group call service is smaller than the second preset bandwidth, the adjusting module 602 decreases the order of the MCS used for the at least one group call service.

Optionally, the adjusting module 602 reduces the order of the MCS used for the at least one group call service, including:

the adjusting module 602 selects N group call services in which the value of the downlink channel quality indicator CQI of a group is smaller than a second threshold from the at least one group call service, where the value of the CQI of a group is an average value of the values of the CQIs reported by the multiple terminals 102 included in the group, and N is a positive integer;

the adjusting module 602 reduces the order of the N MCSs respectively adopted for the N group call services.

Optionally, an average value of CQI values reported by a plurality of terminals 102 included in a group is:

the average value of the CQI values reported by the terminals 102 in RRC connected state and the CQI values reported by the terminals 102 in RRC IDLE state in the RRC control protocol in one group.

Wherein, the base station 101 may be configured to perform the method provided by the embodiment shown in fig. 2. Therefore, regarding the functions that can be realized by each functional module in the base station 101, reference may be made to the corresponding description in the embodiment shown in fig. 2, which is not repeated herein.

In the embodiment of the invention, the base station adjusts the order of the MCS according to the order of the preset MCS for the bandwidth allocated to the at least one group calling service, if the bandwidth allocated to the at least one group calling service is larger than the first preset bandwidth, the bandwidth allocated to the at least one group calling service by the base station is larger and may be close to the maximum bandwidth supported by the base station, and at the moment, the order of the MCS can be increased by the base station, so that the bandwidth is reallocated for the at least one group calling service according to the order of the increased MCS, so that the amount of data carried by one allocated RB is larger, and the number of RBs to be allocated is smaller, thereby saving transmission resources and improving the capacity of the system.

It will be clear to those skilled in the art that, for convenience and simplicity of description, the foregoing division of the functional modules is merely used as an example, and in practical applications, the above function distribution may be performed by different functional modules according to needs, that is, the internal structure of the device is divided into different functional modules to perform all or part of the above described functions. For the specific working processes of the system, the apparatus and the unit described above, reference may be made to the corresponding processes in the foregoing method embodiments, and details are not described here again.

In the embodiments provided in the present invention, it should be understood that the disclosed apparatus and method may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the modules or units is only one logical division, and there may be other divisions when actually implemented, for example, a plurality of units or components may be combined or may be integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.

In addition, functional units in the embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit.

The integrated unit, if implemented in the form of a software functional unit and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present application may be substantially implemented or contributed by the prior art, or all or part of the technical solution may be embodied in a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, a network device, or the like) or a processor (processor) to execute all or part of the steps of the method according to the embodiments of the present application. And the aforementioned storage medium includes: various media capable of storing program codes, such as a Universal Serial Bus flash disk (usb flash disk), a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk, or an optical disk.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.

Claims

1. A method for adjusting modulation coding mode comprises the following steps:

2. The method of claim 1, wherein the base station increasing the order of the MCS employed for the at least one group call service comprises:

3. The method of claim 1, further comprising:

4. The method of claim 3, wherein the base station reducing the order of the MCS employed for the at least one group call service comprises:

5. The method according to claim 2 or 4, wherein the average value of the CQI reported by the plurality of terminals included in the group is:

6. A base station, comprising:

7. The base station of claim 6, wherein the adjusting module increases the order of the MCS used for the at least one group call service, comprising:

8. The base station of claim 6, wherein the adjustment module is further configured to:

9. The base station of claim 8, wherein the adjusting module decreases the order of the MCS used for the at least one group call service, comprising:

10. The base station according to claim 7 or 9, wherein the average value of the CQI values reported by the plurality of terminals included in the group is: