CN106937302A - A kind of determination LTE-TDD Zones support the method and device of capacity - Google Patents

Abstract

The invention discloses the method and device that a kind of determination LTE-TDD Zones support capacity, according to descending available RB quantity, the descending RB quantity of average each VoLTE business occupancy and the first factor of influence, determine that PDSCH can support the number of users of VoLTE business；The up RB quantity taken according to up available RB quantity, average each VoLTE business and the second factor of influence, determine that PUSCH can support the number of users of VoLTE business；According to the RE quantity in each VoLTE service period, the average CCE degree of polymerization of cell and the 3rd factor of influence, determine that PDCCH can support the number of users for dispatching VoLTE uplink services and the number of users for dispatching VoLTE downlink business.The method and device for determining that LTE-TDD Zones support capacity is the embodiment of the invention provides, has important meaning for overall plan of network and service development strategy.

Description

Method and device for determining LTE-TDD cell service support capacity

Technical Field

The present invention relates to the field of mobile communications technologies, and in particular, to a method and an apparatus for determining LTE-TDD (Time Division duplex long term Evolution) cell service support capacity.

Background

Voice over LTE (Voice over LTE, Voice solution for LTE bearer) is a Voice service based on IMS (IP multimedia subsystem), and can implement unification of data and Voice services in the same network. VoLTE is a new Voice solution, belonging to VoIP (Voice over Internet Protocol) technology, and is a solution carried and implemented by LTE (Long Term Evolution) network, which will gradually replace the mainstream Voice solutions GSM (Global System for Mobile Communication) and CSFB (Circuit Switched Fallback). Therefore, the accurate evaluation of the LTE cell to the VoLTE service support capacity has important significance for the overall network planning and the service development strategy.

For the supportable capacity of a cell of a packet domain network represented by LTE technology, a scheme using network utilization, statistics of the maximum number of access users or the number of active users as a measure is generally used. Because the capacity of the packet domain service depends on the frequency spectrum efficiency and is simultaneously restricted and influenced by factors such as different service quality requirements, wireless resources, network configuration, wireless environment, characteristic functions and the like, the capacity of the user supported by the LTE cell can only be evaluated from the network load perspective through the statistics of the network utilization rate, the maximum number of access users or the number of activated users, and the relatively specific number of the supportable users can not be well provided for the specific service.

In summary, the supportable capacity of the existing LTE cell cannot be used as a method for measuring the support capacity of the VoLTE service, and because of the particularity of the LTE-TDD network in the time domain, the VoLTE service in the LTE-TDD network is not yet applied in a large scale, a method for accurately evaluating the support capacity of the LTE-TDD cell for the VoLTE service is temporarily absent.

Disclosure of Invention

The invention provides a method and a device for determining the service support capacity of an LTE-TDD cell, which are used for solving the problem that a method for accurately evaluating the support capacity of the LTE-TDD cell to the VoLTE service is not available temporarily in the prior art.

The embodiment of the invention discloses a method for determining LTE-TDD cell service support capacity, which comprises the following steps:

according to the number of RB (Resource Block) available for downlinkQuantity, average Downlink RB number occupied by each VoLTE service and first influence factor, and determining user quantity U of PDSCH (Physical Downlink Shared Channel) capable of supporting VoLTE service_PDSCH；

Determining a user number U of a PUSCH (Physical Uplink Shared Channel) capable of supporting the VoLTE service according to the number of the Uplink available RBs, the average number of the Uplink RBs occupied by each VoLTE service and the second influence factor_PUSCH；

Determining a user number U (Physical Downlink Control channel) which can be supported by a PDCCH (Physical Downlink Control channel) for scheduling a VoLTE uplink service according to the number of resource elements RE in each VoLTE service period, the cell average CCE (Control channel element) polymerization degree and a third influence factor_{PDCCH_UL}And user number U for scheduling VoLTE downlink service_{PDCCH_DL}；

According to the U_PDSCHThe U_PUSCHThe U_{PDCCH_UL}And the U_{PDCCH_DL}And determining the support capacity of the LTE-TDD cell to the VoLTE service.

Optionally, the number U of users of the downlink physical shared channel PDSCH capable of supporting the VoLTE service is determined according to the number of downlink available resource blocks RB, the number of downlink RBs occupied by each VoLTE service on average, and the first impact factor_PDSCHThe method comprises the following steps:

determining the number U of users of the PDSCH capable of supporting VoLTE service according to the following formula_PDSCH：

Wherein,for the number of RBs available for the downlink,for the average number of downlink RBs occupied per VoLTE service,for the number of TTIs (Transmission Time intervals) in each VoLTE service period, the first impact factor includes: retransmission factor F_RetransTime Division Duplex (TDD) factorVoice activation factor VAF.

Optionally, the average number of downlink RBs occupied by each VoLTE service isDetermined according to the following formula:

wherein, M is the maximum allocable downlink RB quantity of the LTE-TDD cell; i is the number of RBs corresponding to different downlink CQI (channel quality Indicator) grades, and is determined according to the CQI grade and the size of data to be transmitted; p_iFor the distribution proportion of downlink users corresponding to the RB number i, the P_iDetermining according to cell MR (Measurement Report) data;

the number of RBs available for downlinkDetermined according to the following formula:

wherein,for the total number of RBs in downlink, N_SIBThe number of RBs occupied for SIB (System information Block),Number of downlink RBs occupied for RRC (Radio Resource Control) signaling, N_PagingThe number of RBs occupied for paging.

Optionally, the user number U for the uplink physical shared channel PUSCH to support the VoLTE service is determined according to the number of uplink RBs available for uplink, the average number of uplink RBs occupied by each VoLTE service, and the second impact factor_PUSCHThe method comprises the following steps:

determining the number U of users of the PUSCH capable of supporting VoLTE service according to the following formula_PUSCH：

Wherein,the number of RBs available for the uplink is,for the average number of uplink RBs occupied by each VoLTE service, the second impact factor includes: retransmission factor F_RetransUplink time division duplex TDD factorPhysical random access channel PRACH factor F_PRACHVoice activation factor VAF.

Optionally, the average number of uplink RBs occupied by each VoLTE service isDetermined according to the following formula:

wherein, N is the maximum allocable uplink RB quantity of the LTE-TDD cell; j is the number of RBs corresponding to different Modulation and Coding Scheme (MCS) levels of the uplink_，The j is determined according to the MCS level and the size of the data to be transmitted; p_jFor the distribution proportion of the uplink users with the RB number j, the P_jDetermining according to the cell MR data;

the number of RBs available for uplinkDetermined according to the following formula:

wherein,for the total number of uplink RBs,The number of RBs occupied by the physical uplink control channel PUCCH,The number of uplink RBs occupied for RRC signaling.

Optionally, the determination that the PDCCH can support the user number U for scheduling the VoLTE uplink service according to the number of resource elements RE in each VoLTE service period, the cell average control channel element CCE aggregation level, and the third impact factor is performed_{PDCCH_UL}And user number U for scheduling VoLTE downlink service_{PDCCH_DL}The method comprises the following steps:

the resource unit RE number in each VoLTE service period comprises the RE number which can be used by the PDCCH for scheduling downlink service in each VoLTE service period and the RE number which can be used by the PDCCH for scheduling uplink service in each VoLTE service period;

determining the number U of users which can be supported by the PDCCH for scheduling VoLTE downlink service according to the following formula_{PDCCH_DL}：

Determining the number U of users which can be supported by the PDCCH for scheduling VoLTE uplink service according to the following formula_{PDCCH_UL}：

Where R is the number of REs available per CCE,for the number of REs that can be used for scheduling downlink services in the PDCCH in each VoLTE service period,For the number of REs available for the PDCCH to schedule uplink traffic in each VoLTE traffic period,is the cell average CCE aggregation level; the third influencing factor comprises: retransmission factor F_RetransSPS (Semi-Persistent Scheduling) gain F_SPSVoice activation factor VAF.

Optionally, the PDCCH may be used to schedule the number of REs of the downlink service in each VoLTE service periodDetermined according to the following formula:

wherein k is the subframe number in each VoLTE service period, P is the maximum subframe number in each VoLTE service period,the total number of REs in a symbol occupied for PDCCH available for scheduling downlink traffic,the number of REs occupied by a CRS (Cell Reference Signal) channel in a symbol occupied by a PDCCH (physical Downlink control channel) for scheduling downlink traffic,The number of REs occupied by a PHICH (Physical hybrid automatic Repeat-Request Indicator Channel) in a symbol occupied by a PDCCH (Physical Downlink control Channel) for scheduling downlink traffic,The number of REs occupied by a PCFICH (Physical control format Indicator Channel) in a symbol occupied by a PDCCH for scheduling a downlink service;

the PDCCH can be used for scheduling the number of REs of the uplink service in each VoLTE service periodDetermined according to the following formula:

wherein,for the total number of REs in a symbol occupied by PDCCH available for scheduling uplink traffic,the number of REs occupied by CRS channels within symbols occupied by PDCCH for scheduling uplink traffic,The number of REs occupied by the PHICH in the symbol occupied by the PDCCH for scheduling the uplink traffic,The number of REs occupied by PCFICH in a symbol occupied by a PDCCH used for scheduling uplink service;

the cell average CCE aggregation levelDetermined according to the following formula:

wherein x is the aggregation level, Q is the maximum aggregation level,for the proportion of the users distributed under different aggregation levelsDetermined from the MR data.

Optionally, the U is_PDSCHThe U_PUSCHThe U_{PDCCH_UL}And the U_{PDCCH_DL}Determining the support capacity of the LTE-TDD cell for the VoLTE service, including:

will be the U_PDSCHThe U_PUSCHThe U_{PDCCH_UL}And the U_{PDCCH_DL}And the medium minimum value is used as the support capacity of the LTE-TDD cell for the VoLTE service.

The embodiment of the invention also provides a device for determining the service support capacity of the LTE-TDD cell, which comprises the following steps:

a PDSCH determining module: the method is used for determining the number U of users of the PDSCH capable of supporting the VoLTE service according to the number of downlink available Resource Blocks (RBs), the number of downlink RBs occupied by each VoLTE service on average and a first influence factor_PDSCH；

A PUSCH determination module: the method is used for determining the number U of users of the PUSCH capable of supporting the VoLTE service according to the number of the uplink available RBs, the average number of the uplink RBs occupied by each VoLTE service and the second influence factor_PUSCH；

A PDCCH determination module: the method is used for determining the number U of users for scheduling VoLTE uplink service which can be supported by PDCCH according to the number of Resource Elements (REs) in each VoLTE service period, the polymerization degree of CCE (cell average control channel element) and a third influence factor_{PDCCH_UL}And user number U for scheduling VoLTE downlink service_{PDCCH_DL}；

A result determination module: for according to the U_PDSCHThe U_PUSCHThe U_{PDCCH_UL}And the U_{PDCCH_DL}And determining the support capacity of the LTE-TDD cell to the VoLTE service.

Optionally, the PDSCH determining module is further configured to:

determining the number U of users of the PDSCH capable of supporting VoLTE service according to the following formula_PDSCH：

Wherein,for the number of RBs available for the downlink,for the average number of downlink RBs occupied per VoLTE service,for each number of TTIs in a VoLTE service period, the first impact factor includes: retransmission factor F_RetransDownlink time division duplex TDD factorVoice activation factor VAF.

Optionally, the PDSCH determining module is further configured to:

determining the number of downlink RBs occupied by each VoLTE service according to the following formula

Wherein, M is the maximum allocable downlink RB quantity of the LTE-TDD cell; i is the number of RBs corresponding to different downlink channel quality indicator CQI grades, and the i is determined according to the CQI grades and the size of data to be transmitted; p_iFor the distribution proportion of downlink users corresponding to the RB number i, the P_iDetermining according to the MR data of the cell measurement report;

determining the number of RBs available for downlink according to the following formula

Wherein,for the total number of RBs in downlink, N_SIBThe number of RBs occupied by the system information block SIB,Number of downlink RBs, N occupied for radio resource control RRC signalling_PagingThe number of RBs occupied for paging.

Optionally, the PUSCH determining module is further configured to:

determining the number U of users of the PUSCH capable of supporting VoLTE service according to the following formula_PUSCH：

Wherein,the number of RBs available for the uplink is,for the average number of uplink RBs occupied by each VoLTE service, the second impact factor includes: retransmission factor F_RetransUplink time division duplex TDD factorPhysical random access channel PRACH factor F_PRACHVoice activation factor VAF.

Optionally, the PUSCH determining module is further configured to:

determining the number of uplink RBs occupied by each VoLTE service according to the following formula

Wherein, N is the maximum allocable uplink RB quantity of the LTE-TDD cell; j is the number of RBs corresponding to different modulation coding strategy MCS levels of the uplink_，The j is determined according to the MCS level and the size of the data to be transmitted; p_jFor the distribution proportion of the uplink users with the RB number j, the P_jDetermining according to the MR data of the cell measurement report;

determining the number of RBs available for uplink according to the following formula

Wherein,for the total number of uplink RBs,The number of RBs occupied by the physical uplink control channel PUCCH,The number of uplink RBs occupied for RRC signaling.

Optionally, the number of resource elements RE in each VoLTE service period includes the number of REs that the PDCCH can be used to schedule the downlink service in each VoLTE service period and the number of REs that the PDCCH can be used to schedule the uplink service in each VoLTE service period, and the PDCCH determining module is further configured to:

determining the number of users that the PDCCH can support for scheduling VoLTE downlink service according to the following formulaU_{PDCCH_DL}：

Determining the number U of users which can be supported by the PDCCH for scheduling VoLTE uplink service according to the following formula_{PDCCH_UL}：

Where R is the number of REs available per CCE,for the number of REs that can be used for scheduling downlink services in the PDCCH in each VoLTE service period,For the number of REs available for the PDCCH to schedule uplink traffic in each VoLTE traffic period,is the cell average CCE aggregation level; the third influencing factor comprises: retransmission factor F_RetransSemi-persistent scheduling (SPS) gain F_SPSVoice activation factor VAF.

Optionally, the PDCCH determining module is further configured to:

determining the number of REs which can be used for scheduling downlink service by PDCCH in each VoLTE service period according to the following formula

Wherein k isThe subframe number in each VoLTE service period, P is the maximum subframe number in each VoLTE service period,the total number of REs in a symbol occupied for PDCCH available for scheduling downlink traffic,the number of REs occupied by a Cell Reference Signal (CRS) channel in a symbol occupied by a PDCCH for scheduling downlink traffic,The number of REs occupied by a physical hybrid automatic repeat indicator channel PHICH in a symbol occupied by a PDCCH for scheduling downlink traffic,Indicating the number of REs occupied by a PCFICH (physical control format indicator channel) in a symbol occupied by a PDCCH (physical control channel) for scheduling downlink services;

determining the number of REs which can be used for scheduling uplink service by PDCCH in each VoLTE service period according to the following formula

Wherein,for the total number of REs in a symbol occupied by PDCCH available for scheduling uplink traffic,the number of REs occupied by CRS channels within symbols occupied by PDCCH for scheduling uplink traffic,The number of REs occupied by the PHICH in the symbol occupied by the PDCCH for scheduling the uplink traffic,The number of REs occupied by PCFICH in a symbol occupied by a PDCCH used for scheduling uplink service;

determining the cell average CCE aggregation level according to the following formula

Wherein x is the aggregation level, Q is the maximum aggregation level,for the proportion of the users distributed under different aggregation levelsDetermined from the MR data.

Optionally, the result determining module is further configured to:

will be the U_PDSCHThe U_PUSCHThe U_{PDCCH_UL}And the U_{PDCCH_DL}And the medium minimum value is used as the support capacity of the LTE-TDD cell for the VoLTE service.

The embodiment of the invention provides a method and a device for determining the support capacity of an LTE-TDD cell service, wherein the number of users of a PDSCH capable of supporting a VoLTE service is determined according to the number of RBs available for downlink, the number of downlink RBs occupied by each VoLTE service on average and a first influence factor; determining the number of users of the PUSCH capable of supporting the VoLTE service according to the number of available uplink RBs, the number of uplink RBs occupied by each VoLTE service on average and a second influence factor; determining the number of users which can be supported by the PDCCH for scheduling the VoLTE uplink service and the number of users for scheduling the VoLTE downlink service according to the number of REs in each VoLTE service period, the average CCE polymerization degree of the cell and a third influence factor; and finally determining the support capacity of the LTE-TDD cell to the VoLTE service. The method and the device for determining the LTE-TDD cell service support capacity provided by the embodiment of the invention have important significance for network overall planning and service development strategies.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive exercise.

Fig. 1 is a schematic flowchart of a method for determining a support capacity of an LTE-TDD cell for a VoLTE service according to an embodiment of the present invention;

fig. 2 is a schematic diagram of a method for determining a downlink user distribution ratio according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of an apparatus for determining a support capacity of a LTE-TDD cell for a VoLTE service according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention clearer, the present invention will be described in further detail with reference to the accompanying drawings, and it is apparent that the described embodiments are only a part of the embodiments of the present invention, not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The VoLTE service belongs to a packet domain service, and the capacity of the VoLTE service directly depends on the spectrum efficiency, as shown in table 1, because of the mutual restriction and influence of different service quality requirements, wireless resources, network configuration, wireless environment, characteristic functions and other factors, the support capacity of the LTE system to the VoLTE service is not a fixed value, and because of the particularity of the LTE-TDD network in the time domain, a model for estimating the VoLTE service capacity needs to be formed by constraining various influence conditions.

For different physical channels, network configuration, resource allocation mode, resource occupation quantity, etc. are different. As can be seen from table 1, the supported capacity of the VoLTE service is affected by the PDSCH capacity, the PUSCH capacity, and the PUSCH capacity, so that the supportable capacities of various physical channels need to be calculated, and finally, the supported capacity of the LTE-TDD cell for the VoLTE service is determined comprehensively according to the supportable capacities of the physical channels.

Table 1 factors affecting VoLTE supportable capacity

Fig. 1 schematically shows a flowchart of a method for determining a support capacity of an LTE-TDD cell for a VoLTE service according to an embodiment of the present invention, where the method includes:

step 101: determining the number U of users of PDSCH capable of supporting VoLTE service according to the number of available downlink RBs, the number of downlink RBs occupied by each VoLTE service on average and a first influence factor_PDSCH。

Specifically, the number U of users whose PDSCH can support VoLTE service is determined according to formula (1)_PDSCH：

Wherein,in order to determine the number of RBs available for downlink,to average the number of downlink RBs occupied per VoLTE service,the number of transmission time intervals TTI per VoLTE service period. The first influencing factor includes: retransmission factor F_RetransDownlink TDD factorVoice activation factor VAF.

Number of downlink RBs occupied per VoLTE service for average in equation (1)Can be determined according to equation (2):

wherein, M is the maximum allocable downlink RB number of the LTE-TDD cell, and since the number of downlink RBs available under the maximum bandwidth of 20M in the LTE system is 100, the value of M is 100.

i is the number of RBs corresponding to different downlink channel quality indicator CQI grades, and i is determined according to the CQI grades and the size of data to be transmitted; p_iFor the downlink user distribution proportion, P, corresponding to the RB number i_iDetermined from the cell measurement report MR data.

Number of RBs available for downlink in equation (1)Determined according to equation (3):

wherein,for the total number of RBs in downlink, N_SIBThe number of RBs occupied by the system information block SIB,Number of downlink RBs, N occupied for radio resource control RRC signalling_PagingThe number of RBs occupied for paging.

Step 102: determining the number U of users of the uplink physical shared channel PUSCH capable of supporting the VoLTE service according to the number of the available RBs in the uplink, the number of uplink RBs occupied by each VoLTE service on average and the second influence factor_PUSCH。

Specifically, the number U of users whose PUSCH can support VoLTE service is determined according to formula (4)_PUSCH：

Wherein,the number of RBs available for the uplink is,the number of uplink RBs occupied for each VoLTE service is averaged. The second influencing factor includes: retransmission factor F_RetransUplink TDD factorPRACH factor F_PRACHVoice activation factor VAF.

For each average V in equation (4)Number of uplink RBs occupied by oLTE serviceFrom equation (5), it is determined:

the N is the maximum allocable uplink RB number of the LTE-TDD cell, and since the number of uplink RBs available under the maximum bandwidth of 20M in the LTE system is 100, the value of N is 100.

j is the number of RBs corresponding to different MCS levels of uplink_，j is determined according to the MCS level and the size of the data to be transmitted; p_jFor the distribution ratio of the uplink users with the number of RBs j, P_jDetermined from the cell MR data.

Number of RBs available for uplink in equation (4)Can be determined according to equation (6):

wherein,for the total number of uplink RBs,The number of RBs occupied by the physical uplink control channel PUCCH,The number of uplink RBs occupied for RRC signaling.

Step 103: according to the number of resource units (RE) in each VoLTE service period, the average cell, CCE polymerization degree and the secondThree influence factors, namely determining the number U of users which can be supported by a Physical Downlink Control Channel (PDCCH) and used for scheduling VoLTE uplink service_{PDCCH_UL}And user number U for scheduling VoLTE downlink service_{PDCCH_DL}。

The resource unit RE number in each VoLTE service period comprises the RE number which can be used by the PDCCH for scheduling downlink service in each VoLTE service period and the RE number which can be used by the PDCCH for scheduling uplink service in each VoLTE service period.

Specifically, it is determined according to formula (7) that the PDCCH can support the number U of users for scheduling VoLTE downlink traffic_{PDCCH_DL}：

Determining the number U of users which can be supported by PDCCH for scheduling VoLTE uplink service according to formula (8)_{PDCCH_UL}：

Where R is the number of available REs per CCE, since 1 CCE corresponds to 9 REGs (Resource element group, RE set), and 1 REG corresponds to 4 available REs, one CCE corresponds to 36 REs, and thus R takes the value of 36.

For the number of REs that can be used for scheduling downlink services in the PDCCH in each VoLTE service period,For the number of REs available for the PDCCH to schedule uplink traffic in each VoLTE traffic period,is a cell flatAverage CCE polymerization degree; the third influencing factor comprises: retransmission factor F_RetransSPS gain F_SPSVoice activation factor VAF.

Number of REs available for PDCCH to schedule downlink traffic in each VoLTE traffic period in equation (7)Can be determined according to equation (9):

wherein k is a subframe number in each VoLTE service period, P is a maximum subframe number in each VoLTE service period, and since the maximum subframe number in each VoLTE service period is 20, the value of P is 20.

The total number of REs in a symbol occupied for PDCCH available for scheduling downlink traffic,the number of REs occupied by CRS channels within symbols occupied by PDCCH for scheduling downlink traffic,The number of REs occupied by the PHICH within a symbol occupied by the PDCCH for scheduling downlink traffic,The number of REs occupied by PCFICH in a symbol occupied by PDCCH for scheduling downlink service;

for the number of REs available for PDCCH to schedule uplink service in each VoLTE service period in equation (8)Can be determined according to equation (10):

wherein,for the total number of REs in a symbol occupied by PDCCH available for scheduling uplink traffic,the number of REs occupied by CRS channels within symbols occupied by PDCCH for scheduling uplink traffic,The number of REs occupied by the PHICH in the symbol occupied by the PDCCH for scheduling the uplink traffic,The number of REs occupied by PCFICH in a symbol occupied by a PDCCH used for scheduling uplink service;

average CCE aggregation level for a cellCan be determined according to equation (11):

wherein x is a polymerization level, Q is a maximum polymerization level, and the value of Q is 4 because PDCCH CCE has four types of polymerization levels;for the proportion of the users distributed at different aggregation levels,determined from the MR data.

It should be noted that, in the embodiment of the present invention, the order of step 101, step 102, and step 103 may be arbitrarily changed, and is not limited herein.

Step 104: according to U_PDSCH、U_PUSCH、U_{PDCCH_UL}And U_{PDCCH_DL}And determining the support capacity of the LTE-TDD cell for the VoLTE service.

Specifically, U determined according to the method_PDSCH、U_PUSCH、U_{PDCCH_UL}And U_{PDCCH_DL}And comparing to obtain a minimum value, and taking the minimum value as the support capacity of the LTE-TDD cell for the VoLTE service.

The embodiment of the invention determines the basis of the LTE-TDD cell on the VoLTE service support capacity as the LTE air interface physical layer characteristic based on the channel resource allocation mode, and has the characteristics of active planning, strong pertinence and high accuracy. The embodiment of the invention combines the analysis of a user model on the basis of the calculation of each physical channel resource, has stronger flexibility and the current network adaptive capacity, and forms a complete estimation method of the VoLTE service support capacity under the LTE-TDD network.

When the LTE-TDD network deploys the VoLTE service, a communication operator can estimate how many scales of VoLTE users can be supported by the existing network resources based on the calculation method provided by the embodiment of the present invention, so as to further formulate a network capacity expansion scheme and a VoLTE user development strategy in combination with a service development target.

The embodiment of the invention provides a method and a device for determining the support capacity of an LTE-TDD cell service, wherein the number of users of a PDSCH capable of supporting a VoLTE service is determined according to the number of RBs available for downlink, the number of downlink RBs occupied by each VoLTE service on average and a first influence factor; determining the number of users of the PUSCH capable of supporting the VoLTE service according to the number of available uplink RBs, the number of uplink RBs occupied by each VoLTE service on average and a second influence factor; determining the number of users which can be supported by the PDCCH for scheduling the VoLTE uplink service and the number of users for scheduling the VoLTE downlink service according to the number of REs in each VoLTE service period, the average CCE polymerization degree of the cell and a third influence factor; and finally determining the support capacity of the LTE-TDD cell to the VoLTE service. The method and the device for determining the LTE-TDD cell service support capacity provided by the embodiment of the invention have important significance for network overall planning and service development strategies.

A method for determining the number of users whose PDSCH can support VoLTE service is described in detail below.

For the number of TTIs per VoLTE service period in equation (1)Generally, for a VoLTE voice frame, 20ms voice packets can be put into one TTI for carrying, so that 20 voice packets of users can be scheduled in 20ms, that is, the number of TTIs in each VoLTE service period is 20.

For retransmission factor F in equation (1)_RetransDepending on the wireless environment, the system may have different retransmission rates, generally with 10% as the convergence target.

For the downlink TDD factor in equation (1)Depending on the TDD frame structure, there are 10 subframes in each frame, and each subframe has 14 OFDM (Orthogonal Frequency Division Multiplexing) symbols. For the downlink channel, the TDD factor may be determined according to equation (12):

for example, the downlink subframe ratio is 2, the special subframe ratio is 7, the number of downlink subframes is 6, the number of symbols available for the special subframe is 20, and the downlink TDD factorIf the PDCCH is further considered to be only used for uplink VoLTE scheduling in downlink subframe numbers 3 and 8, then the effective downlink TDD factor

For the voice activation factor VAF in formula (1), since the voice call has a silent period and an active period, and the data rate of the transmission of the silent period is much lower than the active period, the voice activation factor VAF can be obtained through data acquisition statistics or simulation.

Number of RBs available for downlink in equation (1)Mainly depends on the total number of downlink RBsWhileMay be determined by the frequency bandwidth, e.g., 100 RBs in a 20MHz bandwidth. In order to accurately obtain resources available for service data transmission, the overhead of necessary SIB, Paging, RRC signaling, and the like needs to be removed when determining the number of downlink total RBs. For different bandwidths, the total number of downlink RBs is as shown in table 2:

table 2 total downlink RB number corresponding to different bandwidths

Bandwidth (MHz)	1.4	3	5	10	15	20
							Total number of RBs in downlink	6	15	25	50	75	100

It should be noted that, since the service period of the VoLTE voice packet is 20ms, when calculating the RB resource occupied by the SIB message, the RRC signaling, and the Paging message, the calculation in the time domain takes 20ms as a statistical period.

Number of RBs N occupied for SIB in equation (3)_SIBThe number of RB resources used for transmitting SIB system messages in PDSCH is represented and can be obtained based on the number of RBs required for SIB, the number of RB resources occupied by different SIB messages is different, and taking subframe ratio 2 as an example, the number and the period of resources occupied by the main SIB messages in the connected state are shown in table 3:

TABLE 3 number of RBs occupied by SIB

Number of downlink RBs occupied for RRC signaling in equation (3)Representing RB resources in PDSCH for transmission of RRC signalingThe source number and RRC signaling mainly comprise signaling for call establishment, switching and the like, and a model can be acquired through the current network test acquisition. Taking the voice channel coding rate of Z kbps as an example, if the average size of the RRC signaling for handover is about X Byte, the number of handovers per minute is W, the average size of the signaling for VoLTE call setup is about Y Byte, and the RRC signaling overhead is estimated by a service model for call setup, the number of downlink RBs occupied by the RRC signaling can be determined according to formula (13):

wherein, the numerator is RRC signaling consumed for each call setup and switching in one minute of call, the numerator Z60/0.02 is the size of data volume that can be transmitted by the VoLTE voice packet in one minute, the unit is bit (bit), in order to keep consistent with the unit Byte of the numerator, it needs to be divided by 8, to obtain the number of downlink RBs occupied by the RRC signaling overhead.

The number of resources occupied by Paging in the formula (3) depends on the PCCH channel configuration and the actual Paging load of the network, and can be obtained by collecting the statistical data of the current network.

Number of downlink RBs occupied per VoLTE call averaged in equation (1)According to different wireless environments of users, the number i of RBs corresponding to different downlink CQI grades and the distribution proportion P_iMultiplying to obtain the downlink user distribution ratio P_iThe mathematical model can be selected according to different refinement degrees of the required results, and the mathematical model is determined based on the current network MR acquisition.

In the embodiment of the invention, the number of RBs occupied by each VoLTE call is influenced by different wireless environments and has difference. In the downlink direction, the network acquires the radio quality of the downlink through the CQI reported by the terminal, and after acquiring the amount of data to be transmitted and the CQI, according to the 3GPP (3rd Generation Partnership Project) specification, obtains, through table lookup, how many RBs the network needs to allocate for service use in different CQI classes corresponding to different radio environments.

For downlink user distribution ratio P_iIt can be determined in two ways:

based on the MR data acquisition method: according to the terminal test data, the SINR (Signal to interference plus Noise Ratio), RSRP (Reference Signal receiving Power), and CQI data in the sampling points are obtained, and a corresponding relation between RSRP and CQI or between SINR and CQI is formed by a data fitting method (such as a linear least square method). And then collecting MR data of the whole network cell, carrying out distribution proportion statistics on RSRP or SINR in the MR sampling points, and acquiring the corresponding CQI user distribution proportion according to the distribution proportion of the RSRP or SINR.

The mathematical model method comprises the following steps: taking a concentric circle model as an example, as shown in fig. 2, which is a schematic diagram of a method for determining a downlink user distribution ratio according to an embodiment of the present invention, different RB resource allocation amounts are defined into set wireless quality levels, such as four types of wireless quality levels of a good point, a middle point, and a bad point, where the radial distances of users in the four types of coverage scenarios are the same, and are d, 2d, 3d, and 4d, respectively, and the coverage area of the good point is pi d²The sweet spot coverage area is pi (2d)²-πd²And the coverage area of the middle point is pi (3d)²-π(2d)²The coverage area of the difference point is pi (4d)²-π(3d)²I.e. the model of the user distribution is an excellent point: good point: midpoint: the difference point is 1: 3: 5: 7; thereby obtaining the corresponding downlink user distribution proportion in various scenes.

According to the specific calculation analysis method, the number U of users of PDSCH capable of supporting VoLTE service can be determined_PDSCH。

The following describes a method for determining the number of users whose PUSCH can support VoLTE service in detail.

For TTI within each VoLTE service period in equation (4)Number ofGenerally, for a VoLTE voice frame, 20ms voice packets can be put into one TTI for carrying, so that 20 voice packets of users can be scheduled in 20ms, that is, the number of TTIs in each VoLTE service period is 20.

For retransmission factor F in equation (4)_RetransDepending on the wireless environment, the system may have different retransmission rates, generally with 10% as the convergence target.

For the uplink TDD factor in equation (4)Can be determined from equation (14):

uplink TDD factor for different subframe ratiosThere are different values. If the subframe ratio is 2 and the special subframe configuration is 7, the TDD factor

For the voice activation factor VAF in equation (4), since the voice call has a silent period and an active period, and the data rate of the transmission of the silent period is much lower than the active period, the voice activation factor VAF can be obtained through data acquisition statistics or simulation.

For the PRACH factor F in equation (4)_PRACHOn the uplink resource, the PRACH channel needs to be reserved on a specific frequency domain and time domain for transmitting the random access preamble. The length is different in the time domain according to different PRACH formats, but the PRACH channel always occupies 6 RBs in the frequency domain. PRACH configuration indication mayKnowing the sending times of PRACH within 10ms, looking up table by 3GPP specification for the subframe configuration with the uplink subframe ratio of 2 and the downlink subframe ratio of 7, if PRACH has X sending opportunities within 10ms, F_PRACH＝1-(6*X/90×2)。

Number of RBs available for uplinkMainly depending on the total number of RBs in uplinkWhileMay be determined by the frequency bandwidth, e.g., 100 RBs in a 20MHz bandwidth. In order to accurately obtain resources available for service data transmission, the number of RBs occupied by a necessary PUCCH and the number of uplink RBs occupied by RRC signaling need to be removed when determining the total number of uplink RBs. For different bandwidths, the number of uplink RBs is as described in table 4:

TABLE 4 Total RB uplink quantities corresponding to different bandwidths

Bandwidth (MHz)	1.4	3	5	10	15	20
							Total number of RBs in uplink	6	15	25	50	75	100

Number of RBs occupied for uplink PUCCH in equation (6)May be determined by parameter configuration. For the number of RB resources used for transmission of RRC signaling in the PUSCH in equation (6), it can be obtained in the same manner as described in equation (13).

Number of uplink RBs occupied per VoLTE service on average in equation (1)Because the number of the uplink RBs depends on the scheduling strategy of the system, after the MCS and the data volume to be transmitted are determined, the table is looked up according to the 3GPP specification to obtain the number of PRBs which are required to be allocated by the network to different uplink MCSs corresponding to different wireless environments for service use. Based on the required RB resources corresponding to the different uplink MCSs, the corresponding different uplink user distribution proportions can be respectively selected, and the average number of uplink RBs occupied by each VoLTE service is obtained by summation after the two uplink users are multiplied at different levels. For the user distribution P in equation (5)_jThe method can be obtained by selecting a mathematical model and carrying out statistics on the uplink MCS level according to different refinement degrees of the required result.

According to the specific calculation analysis method, the number U of users of PUSCH capable of supporting VoLTE service can be determined_PUSCH。

A detailed description will be given below of a method for determining the number of users that can be supported by the PDCCH for scheduling the VoLTE uplink service and the number of users for scheduling the VoLTE downlink service.

The PDCCH is used to carry transmission of Downlink Control Information, including Downlink scheduling assignment and uplink scheduling grant, uplink power Control command, paging message scheduling grant, RACH (Random Access Channel) response scheduling grant, and other signaling, and is carried by DCI (Downlink Control Information block), and different users use different DCI resources. The method can occupy the full bandwidth in the frequency domain, and the frequency domain occupies the first n OFDM symbols of each downlink subframe, wherein n < 3.

The PDCCH is allocated in a manner different from that of the PDSCH and the PUSCH, and is allocated on a CCE basis. Since 1 CCE corresponds to 9 REGs and 1 REG corresponds to 4 available REs, one CCE corresponds to 36 REs.

For retransmission factor F in equation (7) and equation (8)_RetransDepending on the wireless environment, the system may have different retransmission rates, generally with 10% as the convergence target.

For the voice activation factor VAF in the formula (7) and the formula (8), since the voice call has the silent period and the active period, and the data rate of the transmission of the silent period is much lower than the active period, the voice activation factor VAF can be obtained through data collection statistics or simulation.

For SPS gain F in equation (7) and equation (8)_SPSThe gain obtained on the PDCCH resource after using the semi-persistent scheduling technique is mainly considered. In order to reduce the expenditure of services which are relatively stable in VoLTE resource scheduling on PDCCH resources, the semi-persistent scheduling SPS function can be started, namely, the resources are scheduled to users for a longer time at one time, so that the maximum number of users which can be simultaneously scheduled by PDCCH channels is increased. The SPS gain can be determined by the ratio of the PDCCH dynamic scheduling times to the semi-static scheduling times within a certain call time.

In addition, since the PDCCH is required to consume PDCCH for allocating uplink and downlink resources, the number of CCEs on the PDCCH for scheduling downlink resources and the number of CCEs on the PDCCH for scheduling uplink resources need to be calculated separately, and are obtained by subtracting the number of REs occupied by the CRS channel, the PHICH channel, and the PCFICH channel from the total number of REs in the control channel.

For in formula (9)And in equation (10) Taking CFI (Control Format Indicator) equal to 3 as an example, that is, 3 OFDM symbols are used for PDCCH, and then the total number of REs used for PDCCH is 1200 × 3 3600 RE., taking subframe ratio 2 as an example, when the requirement of cell uplink scheduling is large, that is, PDCCH of subframe 3 and subframe 8 is completely used for uplink scheduling, the number of available PDCCH CCEs in each subframe is shown in table 5:

TABLE 5 number of CCEs per subframe of PDCCH under subframe configuration 2

PDCCH CCEs have four types of aggregation levels, 1, 2, 4, and 8, and data transmission is performed using different aggregation levels for different radio environments to improve reliability. The four aggregation levels of CCE correspond to different levels of radio quality, and the distribution ratio of users at different aggregation levels in formula (11)The corresponding user distribution proportion can be obtained according to the MR data by acquiring the CCE polymerization degree distribution condition of the PDCCH of the existing network

According to the specific calculation analysis method, the determination method for determining the number of users that the PDCCH can support for scheduling the VoLTE uplink service and the number of users for scheduling the VoLTE downlink service can be determined.

It should be noted that, the number of users of the PDSCH capable of supporting the VoLTE service, the number of users of the PUSCH capable of supporting the VoLTE service, the number of users of the PDCCH capable of supporting the user for scheduling the VoLTE uplink service, and the number of users for scheduling the VoLTE downlink service, which are determined by the above specific calculation analysis method, are finally determined comprehensively for the support capacity of the LTE-TDD cell for the VoLTE service. Specifically, the minimum value may be used as the support capacity of the LTE-TDD cell for the VoLTE service, and the support capacity of the LTE-TDD cell for the VoLTE service may also be determined through curve fitting, which is not limited herein.

Based on the same inventive concept, an apparatus for determining supported capacity of LTE-TDD cell service is further provided in the embodiments of the present invention, as shown in fig. 3, a schematic structural diagram of the apparatus for determining supported capacity of LTE-TDD cell to VoLTE service provided in the embodiments of the present invention includes:

PDSCH determining module 301: the method is used for determining the number U of users of the PDSCH capable of supporting the VoLTE service according to the number of downlink available Resource Blocks (RBs), the number of downlink RBs occupied by each VoLTE service on average and a first influence factor_PDSCH；

The PUSCH determination module 302: the method is used for determining the number U of users of the PUSCH capable of supporting the VoLTE service according to the number of the uplink available RBs, the average number of the uplink RBs occupied by each VoLTE service and the second influence factor_PUSCH；

PDCCH determining module 303: the method is used for determining the number U of users for scheduling VoLTE uplink service which can be supported by PDCCH according to the number of Resource Elements (REs) in each VoLTE service period, the polymerization degree of CCE (cell average control channel element) and a third influence factor_{PDCCH_UL}And user number U for scheduling VoLTE downlink service_{PDCCH_DL}；

The result determination module 304: for in accordance withThe U is_PDSCHThe U_PUSCHThe U_{PDCCH_UL}And the U_{PDCCH_DL}And determining the support capacity of the LTE-TDD cell to the VoLTE service.

Optionally, the PDSCH determining module 301 is further configured to:

determining the number U of users of the PDSCH capable of supporting VoLTE service according to the following formula_PDSCH：

Wherein,for the number of RBs available for the downlink,for the average number of downlink RBs occupied per VoLTE service,for each number of TTIs in a VoLTE service period, the first impact factor includes: retransmission factor F_RetransDownlink time division duplex TDD factorVoice activation factor VAF.

Optionally, the PDSCH determining module 301 is further configured to:

determining the number of downlink RBs occupied by each VoLTE service according to the following formula

Wherein, M is the maximum allocable downlink RB quantity of the LTE-TDD cell; i is the number of RBs corresponding to different downlink channel quality indicator CQI grades, and the i is determined according to the CQI grades and the size of data to be transmitted; p_iFor the distribution proportion of downlink users corresponding to the RB number i, the P_iDetermining according to the MR data of the cell measurement report;

determining the number of RBs available for downlink according to the following formula

Wherein,for the total number of RBs in downlink, N_SIBThe number of RBs occupied by the system information block SIB,Number of downlink RBs, N occupied for radio resource control RRC signalling_PagingThe number of RBs occupied for paging.

Optionally, the PUSCH determining module 302 is further configured to:

determining the number U of users of the PUSCH capable of supporting VoLTE service according to the following formula_PUSCH：

Wherein,the number of RBs available for the uplink is,for the average number of uplink RBs occupied by each VoLTE service, the second impact factor includes: retransmission factor F_RetransUplink time division duplex TDD factorPhysical random access channel PRACH factor F_PRACHVoice activation factor VAF.

Optionally, the PUSCH determining module 302 is further configured to:

determining the number of uplink RBs occupied by each VoLTE service according to the following formula

Wherein, N is the maximum allocable uplink RB quantity of the LTE-TDD cell; j is the number of RBs corresponding to different modulation coding strategy MCS levels of the uplink_，The j is determined according to the MCS level and the size of the data to be transmitted; p_jFor the distribution proportion of the uplink users with the RB number j, the P_jDetermining according to the MR data of the cell measurement report;

determining the number of RBs available for uplink according to the following formula

Wherein,for the total number of uplink RBs,The number of RBs occupied by the physical uplink control channel PUCCH,The number of uplink RBs occupied for RRC signaling.

Optionally, the number of resource elements RE in each VoLTE service period includes the number of REs that the PDCCH can be used to schedule the downlink service in each VoLTE service period and the number of REs that the PDCCH can be used to schedule the uplink service in each VoLTE service period, and the PDCCH determining module 303 is further configured to:

determining the number U of users which can be supported by the PDCCH for scheduling VoLTE downlink service according to the following formula_{PDCCH_DL}：

Determining the number U of users which can be supported by the PDCCH for scheduling VoLTE uplink service according to the following formula_{PDCCH_UL}：

Where R is the number of REs available per CCE,for the number of REs that can be used for scheduling downlink services in the PDCCH in each VoLTE service period,For the number of REs available for the PDCCH to schedule uplink traffic in each VoLTE traffic period,is cell average CDegree of polymerization of CE; the third influencing factor comprises: retransmission factor F_RetransSemi-persistent scheduling (SPS) gain F_SPSVoice activation factor VAF.

Optionally, the PDCCH determining module 303 is further configured to:

determining the number of REs which can be used for scheduling downlink service by PDCCH in each VoLTE service period according to the following formula

Wherein k is the subframe number in each VoLTE service period, P is the maximum subframe number in each VoLTE service period,the total number of REs in a symbol occupied for PDCCH available for scheduling downlink traffic,the number of REs occupied by a Cell Reference Signal (CRS) channel in a symbol occupied by a PDCCH for scheduling downlink traffic,The number of REs occupied by a physical hybrid automatic repeat indicator channel PHICH in a symbol occupied by a PDCCH for scheduling downlink traffic,Indicating the number of REs occupied by a PCFICH (physical control format indicator channel) in a symbol occupied by a PDCCH (physical control channel) for scheduling downlink services;

determining the number of REs which can be used for scheduling uplink service by PDCCH in each VoLTE service period according to the following formula

Wherein,for the total number of REs in a symbol occupied by PDCCH available for scheduling uplink traffic,the number of REs occupied by CRS channels within symbols occupied by PDCCH for scheduling uplink traffic,The number of REs occupied by the PHICH in the symbol occupied by the PDCCH for scheduling the uplink traffic,The number of REs occupied by PCFICH in a symbol occupied by a PDCCH used for scheduling uplink service;

determining the cell average CCE aggregation level according to the following formula

Wherein x is the aggregation level, Q is the maximum aggregation level,for the proportion of the users distributed under different aggregation levelsDetermined from the MR data.

Optionally, the result determining module 304 is further configured to:

will be the U_PDSCHThe U_PUSCHThe U_{PDCCH_UL}And the U_{PDCCH_DL}And the medium minimum value is used as the support capacity of the LTE-TDD cell for the VoLTE service.

The embodiment of the invention determines the basis of the LTE-TDD cell on the VoLTE service support capacity as the LTE air interface physical layer characteristic based on the channel resource allocation mode, and has the characteristics of active planning, strong pertinence and high accuracy. The embodiment of the invention combines the analysis of a user model on the basis of the calculation of each physical channel resource, has stronger flexibility and the current network adaptive capacity, and forms a complete estimation method of the VoLTE service support capacity under the LTE-TDD network.

When the LTE-TDD network deploys the VoLTE service, a communication operator can estimate how many scales of VoLTE users can be supported by the existing network resources based on the calculation method provided by the embodiment of the present invention, so as to further formulate a network capacity expansion scheme and a VoLTE user development strategy in combination with a service development target.

The embodiment of the invention provides a device for determining the support capacity of an LTE-TDD cell service, which determines the number of users of a PDSCH capable of supporting a VoLTE service according to the number of downlink available RBs, the number of downlink RBs occupied by each average VoLTE service and a first influence factor; determining the number of users of the PUSCH capable of supporting the VoLTE service according to the number of available uplink RBs, the number of uplink RBs occupied by each VoLTE service on average and a second influence factor; determining the number of users which can be supported by the PDCCH for scheduling the VoLTE uplink service and the number of users for scheduling the VoLTE downlink service according to the number of REs in each VoLTE service period, the average CCE polymerization degree of the cell and a third influence factor; and finally determining the support capacity of the LTE-TDD cell to the VoLTE service. The device and the method for determining the LTE-TDD cell service support capacity have important significance for network overall planning and service development strategies.

The present 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 flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams 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 apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create a system for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including an instruction system which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

While preferred embodiments of the present invention have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims be interpreted as including preferred embodiments and all such alterations and modifications as fall within the scope of the invention.

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 (16)

1. A method for determining long term evolution LTE-TDD cell service support capacity based on time division duplex is characterized by comprising the following steps:

determining the number U of users of a downlink physical shared channel (PDSCH) capable of supporting the VoLTE service according to the number of downlink available Resource Blocks (RBs), the number of downlink RBs occupied by each voice solution VoLTE service and a first influence factor_PDSCH；

Determining an uplink physical shared channel according to the number of RBs available for uplink, the number of uplink RBs occupied by each VoLTE service on average and a second influence factorUser number U of PUSCH (physical uplink shared channel) capable of supporting VoLTE (voice over long term evolution) service_PUSCH；

Determining the number U of users for scheduling VoLTE uplink service which can be supported by a PDCCH (physical Downlink control channel) according to the number of Resource Elements (REs) in each VoLTE service period, the polymerization degree of CCE (control channel element average) in a cell and a third influence factor_{PDCCH_UL}And user number U for scheduling VoLTE downlink service_{PDCCH_DL}；

According to the U_PDSCHThe U_PUSCHThe U_{PDCCH_UL}And the U_{PDCCH_DL}And determining the support capacity of the LTE-TDD cell to the VoLTE service.

2. The method of claim 1, wherein the determining the number U of users of the downlink physical shared channel PDSCH capable of supporting the VoLTE service is based on the number of downlink available resource blocks RB, the number of downlink RBs occupied by each VoLTE service on average, and the first impact factor_PDSCHThe method comprises the following steps:

determining the number U of users of the PDSCH capable of supporting VoLTE service according to the following formula_PDSCH：

$U_{PDSCH}=\frac{N_{RB}^{DL}\&times;{\mathrm{NB}}_{TTI}^{VoLTE}\&times;(1-F_{\mathrm{Re}trans})\&times;F_{TDD}^{DL}}{\stackrel{\&OverBar;}{N_{DL\_RB}^{VoLTE}}\&times;VAF}$

Wherein,for the number of RBs available for the downlink,for the average number of downlink RBs occupied per VoLTE service,for the number of transmission time intervals, TTIs, in each VoLTE service period, the first impact factor includes: retransmission factor F_RetransDownlink time division duplex TDD factorVoice activationFactor VAF.

3. The method of claim 2, wherein the average number of downlink RBs occupied per VoLTE serviceDetermined according to the following formula:

$\stackrel{\&OverBar;}{N_{DL\_RB}^{VoLTE}}=\underset{i=1}{\overset{M}{\&Sigma;}}(i\&times;P_i)$

wherein, M is the maximum allocable downlink RB quantity of the LTE-TDD cell; i is the number of RBs corresponding to different downlink channel quality indicator CQI grades, and the i is determined according to the CQI grades and the size of data to be transmitted; p_iFor the distribution proportion of downlink users corresponding to the RB number i, the P_iDetermining according to the MR data of the cell measurement report;

the number of RBs available for downlinkDetermined according to the following formula:

$N_{RB}^{DL}=(N_{RB\_ALL}^{DL}-N_{SIB}-N_{RRC}^{PDSCH}-N_{Paging})$

wherein,for the total number of RBs in downlink, N_SIBThe number of RBs occupied by the system information block SIB,Number of downlink RBs, N occupied for radio resource control RRC signalling_PagingThe number of RBs occupied for paging.

4. The method of claim 1, wherein the determination of the number U of users of the uplink physical shared channel PUSCH capable of supporting VoLTE service is performed according to the number of RBs available in uplink, the number of RBs occupied by each VoLTE service in uplink on average, and the second impact factor_PUSCHThe method comprises the following steps:

determining the number U of users of the PUSCH capable of supporting VoLTE service according to the following formula_PUSCH：

$U_{PUSCH}=\frac{N_{RB}^{DL}\&times;{\mathrm{NB}}_{TTI}^{VoLTE}\&times;(1-F_{\mathrm{Re}trans})\&times;F_{TDD}^{DL}\&times;F_{PRACH}}{\stackrel{\&OverBar;}{N_{DL\_RB}^{VoLTE}}\&times;VAF}$

Wherein,the number of RBs available for the uplink is,for the average number of uplink RBs occupied by each VoLTE service, the second impact factor includes: retransmission factor F_RetransUplink time division duplex TDD factorPhysical random access channel PRACH factor F_PRACHVoice activation factor VAF.

5. The method of claim 4, wherein the average number of uplink RBs occupied per VoLTE serviceDetermined according to the following formula:

$\stackrel{\&OverBar;}{N_{UL\_RB}^{VoLTE}}=\underset{j=1}{\overset{N}{\&Sigma;}}(j\&times;P_j)$

wherein, N is the maximum allocable uplink RB quantity of the LTE-TDD cell; j is the number of RBs corresponding to different modulation coding strategy MCS levels of the uplink_，The j is determined according to the MCS level and the size of the data to be transmitted; p_jFor the distribution proportion of the uplink users with the RB number j, the P_jDetermining according to the cell MR data;

the number of RBs available for uplinkDetermined according to the following formula:

$N_{RB}^{UL}=(N_{RB\_ALL}^{UL}-N_{RB}^{PUCCH}-N_{RRC}^{PUSCH})$

wherein,for the total number of uplink RBs,The number of RBs occupied by the physical uplink control channel PUCCH,The number of uplink RBs occupied for RRC signaling.

6. The method of claim 1, wherein the determination of the number of users U that the PDCCH can support for scheduling the VoLTE uplink service is made according to the number of resource elements RE in each VoLTE service period, the cell average control channel element CCE aggregation level, and a third impact factor_{PDCCH_UL}And user number U for scheduling VoLTE downlink service_{PDCCH_DL}The method comprises the following steps:

the resource unit RE number in each VoLTE service period comprises the RE number which can be used by the PDCCH for scheduling downlink service in each VoLTE service period and the RE number which can be used by the PDCCH for scheduling uplink service in each VoLTE service period;

determining the number U of users which can be supported by the PDCCH for scheduling VoLTE downlink service according to the following formula_{PDCCH_DL}：

$U_{PDCCH\_DL}=\frac{ROUNDUP(\stackrel{\&OverBar;}{N_{RE\_DL}^{CONTROL}}/R)\&times;(1-F_{\mathrm{Re}trans})\&times;F_{SPS}}{\stackrel{\&OverBar;}{P^{CCE}}\&times;VAF}$

Determining the number U of users which can be supported by the PDCCH for scheduling VoLTE uplink service according to the following formula_{PDCCH_UL}：

$U_{PDCCH\_UL}=\frac{ROUNDUP(\stackrel{\&OverBar;}{N_{RE\_UL}^{CONTROL}}/R)\&times;(1-F_{\mathrm{Re}trans})\&times;F_{SPS}}{\stackrel{\&OverBar;}{P^{CCE}}\&times;VAF}$

Where R is the number of REs available per CCE,for the number of REs that can be used for scheduling downlink services in the PDCCH in each VoLTE service period,For the number of REs available for the PDCCH to schedule uplink traffic in each VoLTE traffic period,is the cell average CCE aggregation level; the third influencing factor comprises: retransmission factor F_RetransSemi-persistent scheduling (SPS) gain F_SPSVoice activation factor VAF.

7. The method of claim 6, wherein the number of REs available to the PDCCH for scheduling downlink traffic in each VoLTE traffic periodDetermined according to the following formula:

$\stackrel{\&OverBar;}{N_{RE\_DL}^{CONTROL}}=\underset{k=1}{\overset{P}{\&Sigma;}}(N_{kRE\_DL}^{CONTROL}-N_{kRE\_DL}^{CRS}-N_{kRE\_DL}^{PHICH}-N_{kRE\_DL}^{PCFICH})$

wherein k is the subframe number in each VoLTE service period, P is the maximum subframe number in each VoLTE service period,the total number of REs in a symbol occupied for PDCCH available for scheduling downlink traffic,the number of REs occupied by a Cell Reference Signal (CRS) channel in a symbol occupied by a PDCCH for scheduling downlink traffic,The number of REs occupied by a physical hybrid automatic repeat indicator channel PHICH in a symbol occupied by a PDCCH for scheduling downlink traffic,Indicating the number of REs occupied by a PCFICH (physical control format indicator channel) in a symbol occupied by a PDCCH (physical control channel) for scheduling downlink services;

the PDCCH can be used for scheduling the number of REs of the uplink service in each VoLTE service periodDetermined according to the following formula:

$\stackrel{\&OverBar;}{N_{RE\_UL}^{CONTROL}}=\underset{k=1}{\overset{P}{\&Sigma;}}(N_{kRE\_UL}^{CONTROL}-N_{kRE\_UL}^{CRS}-N_{kRE\_UL}^{PHICH}-N_{kRE\_UL}^{PCFICH})$

wherein,for the total number of REs in a symbol occupied by PDCCH available for scheduling uplink traffic,the number of REs occupied by CRS channels within symbols occupied by PDCCH for scheduling uplink traffic,The number of REs occupied by the PHICH in the symbol occupied by the PDCCH for scheduling the uplink traffic,The number of REs occupied by PCFICH in a symbol occupied by a PDCCH used for scheduling uplink service;

the cell average CCE aggregation levelDetermined according to the following formula:

$\stackrel{\&OverBar;}{P^{CCE}}=\underset{x=1}{\overset{Q}{\&Sigma;}}{2}^{(x-1)}{P}_x^{CCE}$

wherein x is the aggregation level, Q is the maximum aggregation level,for the proportion of the users distributed under different aggregation levelsDetermined from the MR data.

8. The method according to any one of claims 1 to 7, wherein the U is as defined in_PDSCHThe U_PUSCHThe U_{PDCCH_UL}And the U_{PDCCH_DL}Determining the support capacity of the LTE-TDD cell for the VoLTE service, including:

will be the U_PDSCHThe U_PUSCHThe U_{PDCCH_UL}And the U_{PDCCH_DL}And the medium minimum value is used as the support capacity of the LTE-TDD cell for the VoLTE service.

9. An apparatus for determining LTE-TDD cell traffic support capacity, comprising:

a PDSCH determining module: the method is used for determining the number U of users of the PDSCH capable of supporting the VoLTE service according to the number of downlink available Resource Blocks (RBs), the number of downlink RBs occupied by each VoLTE service on average and a first influence factor_PDSCH；

A PUSCH determination module: for availability according to uplinkThe number of RBs, the number of uplink RBs occupied by each VoLTE service on average and a second influence factor are used for determining the number U of users of PUSCH capable of supporting the VoLTE service_PUSCH；

A PDCCH determination module: the method is used for determining the number U of users for scheduling VoLTE uplink service which can be supported by PDCCH according to the number of Resource Elements (REs) in each VoLTE service period, the polymerization degree of CCE (cell average control channel element) and a third influence factor_{PDCCH_UL}And user number U for scheduling VoLTE downlink service_{PDCCH_DL}；

A result determination module: for according to the U_PDSCHThe U_PUSCHThe U_{PDCCH_UL}And the U_{PDCCH_DL}And determining the support capacity of the LTE-TDD cell to the VoLTE service.

10. The apparatus of claim 9, wherein the PDSCH determining module is further configured to:

determining the number U of users of the PDSCH capable of supporting VoLTE service according to the following formula_PDSCH：

$U_{PDSCH}=\frac{N_{RB}^{DL}\&times;{\mathrm{NB}}_{TTI}^{VoLTE}\&times;(1-F_{\mathrm{Re}trans})\&times;F_{TDD}^{DL}}{\stackrel{\&OverBar;}{N_{DL\_RB}^{VoLTE}}\&times;VAF}$

Wherein,for the number of RBs available for the downlink,for the average number of downlink RBs occupied per VoLTE service,for each number of TTIs in a VoLTE service period, the first impact factor includes: retransmission factor F_RetransDownlink time division duplex TDD factorVoice activation factor VAF.

11. The apparatus of claim 10, wherein the PDSCH determining module is further configured to:

determining the number of downlink RBs occupied by each VoLTE service according to the following formula

$\stackrel{\&OverBar;}{N_{DL\_RB}^{VoLTE}}=\underset{i=1}{\overset{M}{\&Sigma;}}(i\&times;P_i)$

Wherein, M is the maximum allocable downlink RB quantity of the LTE-TDD cell; i is the number of RBs corresponding to different downlink channel quality indicator CQI grades, and the i is determined according to the CQI grades and the size of data to be transmitted; p_iFor the distribution proportion of downlink users corresponding to the RB number i, the P_iDetermining according to the MR data of the cell measurement report;

determining the number of RBs available for downlink according to the following formula

$N_{RB}^{DL}=(N_{RB\_ALL}^{DL}-N_{SIB}-N_{RRC}^{PDSCH}-N_{Paging})$

Wherein,for the total number of RBs in downlink, N_SIBThe number of RBs occupied by the system information block SIB,Number of downlink RBs, N occupied for radio resource control RRC signalling_PagingThe number of RBs occupied for paging.

12. The apparatus of claim 9, wherein the PUSCH determining module is further configured to:

determining the number U of users of the PUSCH capable of supporting VoLTE service according to the following formula_PUSCH：

$U_{PUSCH}=\frac{N_{RB}^{DL}\&times;{\mathrm{NB}}_{TTI}^{VoLTE}\&times;(1-F_{\mathrm{Re}trans})\&times;F_{TDD}^{UL}\&times;F_{PRACH}}{\stackrel{\&OverBar;}{N_{DL\_RB}^{VoLTE}}\&times;VAF}$

Wherein,the number of RBs available for the uplink is,for the average number of uplink RBs occupied by each VoLTE service, the second impact factor includes: retransmission factor F_RetransUplink time division duplex TDD factorPhysical random access channel PRACH factor F_PRACHVoice activation factor VAF.

13. The apparatus of claim 12, wherein the PUSCH determining module is further configured to:

determining the number of uplink RBs occupied by each VoLTE service according to the following formula

$\stackrel{\&OverBar;}{N_{UL\_RB}^{VoLTE}}=\underset{j=1}{\overset{N}{\&Sigma;}}(j\&times;P_j)$

Wherein, N is the maximum allocable uplink RB quantity of the LTE-TDD cell; j is the number of RBs corresponding to different modulation coding strategy MCS levels of the uplink_，The j is determined according to the MCS level and the size of the data to be transmitted; p_jFor the distribution proportion of the uplink users with the RB number j, the P_jDetermining according to the MR data of the cell measurement report;

determining the number of RBs available for uplink according to the following formula

$N_{RB}^{UL}=(N_{RB\_ALL}^{UL}-N_{RB}^{PUCCH}-N_{RRC}^{PUSCH})$

Wherein,for the total number of uplink RBs,The number of RBs occupied by the physical uplink control channel PUCCH,The number of uplink RBs occupied for RRC signaling.

14. The apparatus of claim 9, wherein the number of Resource Elements (REs) in each VoLTE service period includes a number of REs available to the PDCCH for scheduling downlink services in each VoLTE service period and a number of REs available to the PDCCH for scheduling uplink services in each VoLTE service period, and wherein the PDCCH determination module is further configured to:

determining the number U of users which can be supported by the PDCCH for scheduling VoLTE downlink service according to the following formula_{PDCCH_DL}：

$U_{PDCCH\_DL}=\frac{ROUNDUP(\stackrel{\&OverBar;}{N_{RE\_DL}^{CONTROL}}/R)\&times;(1-F_{\mathrm{Re}trans})\&times;F_{SPS}}{\stackrel{\&OverBar;}{P^{CCE}}\&times;VAF}$

Determining the number U of users which can be supported by the PDCCH for scheduling VoLTE uplink service according to the following formula_{PDCCH_UL}：

$U_{PDCCH\_UL}=\frac{ROUNDUP(\stackrel{\&OverBar;}{N_{RE\_UL}^{CONTROL}}/R)\&times;(1-F_{\mathrm{Re}trans})\&times;F_{SPS}}{\stackrel{\&OverBar;}{P^{CCE}}\&times;VAF}$

Where R is the number of REs available per CCE,for the number of REs that can be used for scheduling downlink services in the PDCCH in each VoLTE service period,For the number of REs available for the PDCCH to schedule uplink traffic in each VoLTE traffic period,is the cell average CCE aggregation level; the third influencing factor comprises: heavy loadFactor F_RetransSemi-persistent scheduling (SPS) gain F_SPSVoice activation factor VAF.

15. The apparatus of claim 14, wherein the PDCCH determination module is further configured to:

determining the number of REs which can be used for scheduling downlink service by PDCCH in each VoLTE service period according to the following formula

$\stackrel{\&OverBar;}{N_{RE\_DL}^{CONTROL}}=\underset{k=1}{\overset{P}{\&Sigma;}}(N_{kRE\_DL}^{CONTROL}-N_{kRE\_DL}^{CRS}-N_{kRE\_DL}^{PHICH}-N_{kRE\_DL}^{PCFICH})$

Wherein k is the subframe number in each VoLTE service period, P is the maximum subframe number in each VoLTE service period,the total number of REs in a symbol occupied for PDCCH available for scheduling downlink traffic,the number of REs occupied by a Cell Reference Signal (CRS) channel in a symbol occupied by a PDCCH for scheduling downlink traffic,The number of REs occupied by a physical hybrid automatic repeat indicator channel PHICH in a symbol occupied by a PDCCH for scheduling downlink traffic,Indicating the number of REs occupied by a PCFICH (physical control format indicator channel) in a symbol occupied by a PDCCH (physical control channel) for scheduling downlink services;

determining the number of REs which can be used for scheduling uplink service by PDCCH in each VoLTE service period according to the following formula

$\stackrel{\&OverBar;}{N_{RE\_UL}^{CONTROL}}=\underset{k=1}{\overset{P}{\&Sigma;}}(N_{kRE\_UL}^{CONTROL}-N_{kRE\_UL}^{CRS}-N_{kRE\_UL}^{PHICH}-N_{kRE\_UL}^{PCFICH})$

Wherein,for the total number of REs in a symbol occupied by PDCCH available for scheduling uplink traffic,the number of REs occupied by CRS channels within symbols occupied by PDCCH for scheduling uplink traffic,The number of REs occupied by the PHICH in the symbol occupied by the PDCCH for scheduling the uplink traffic,The number of REs occupied by PCFICH in a symbol occupied by a PDCCH used for scheduling uplink service;

determining the cell average CCE aggregation level according to the following formula

$\stackrel{\&OverBar;}{P^{CCE}}=\underset{x=1}{\overset{Q}{\&Sigma;}}{2}^{(x-1)}{P}_x^{CCE}$

Wherein x is the aggregation level, Q is the maximum aggregation level,for the proportion of the users distributed under different aggregation levelsDetermined from the MR data.

16. The apparatus of any of claims 9-15, wherein the result determination module is further configured to:

will be the U_PDSCHThe U_PUSCHThe U_{PDCCH_UL}And the U_{PDCCH_DL}And the medium minimum value is used as the support capacity of the LTE-TDD cell for the VoLTE service.