CN103024908B - Method for self-adaptive adjustment on symbol occupation amount of PDCCH (Physical Downlink Control Channel) - Google Patents

Abstract

The invention provides a method for self-adaptive adjustment on symbol occupation amount of a PDCCH (Physical Downlink Control Channel). The method comprises the following steps of: A, periodically detecting the degree of satisfaction to cell service within a period of time; B, judging whether the degree of satisfaction to the cell service is lower than a first threshold, and if so, executing a step C, otherwise, returning back to execute the step A; C, calculating the occupation rate of cell bandwidth resources, judging whether the occupation rate of the cell bandwidth resources is lower than a second threshold, and if so, executing a step D, otherwise, executing a step E; D, increasing the symbol occupation amount of the PDCCH, and returning back to the step A; E, acquiring the quantity of current system users, and judging whether the user quantity is lower than a third threshold, and if so, executing a step F, otherwise, returning back to the step A; and F, reducing the symbol occupation amount of the PDCCH, and returning back to the step A.

Description

A kind of self-adaptative adjustment PDCCH takies the method for symbolic number

Technical field

The present invention relates to wireless communication technology field, particularly relate to a kind of method that self-adaptative adjustment Physical Downlink Control Channel (PDCCH) takies symbolic number.

Background technology

When UE carries out data traffic transmission, need the physical resource obtaining required for up-downgoing transfer of data at the Downlink Control Information (DCI, Downlink ControlInformation) of public and dedicated search spatially blind check Physical Downlink Control Channel (PDCCH) by Hashing algorithm.First blind check process needs to take sign resources and PCFICH and physical mixing retransmission indicating chanel (PHICH, Physical Hybrid ARQ IndicatorChannel) take resource situation to calculate control channel particle (CCE) space size and terminal blind check original position (relevant to Radio Network Temporary Identifier (RNTI)) by the PDCCH of Physical Control Format Indicator Channel (PCFICH) channel instruction.Community is successfully established resource grains subgroup (REG) resource that rear PCFICH and PHICH take and fixes, therefore the sign resources that takies of PDCCH and the linear relation of CCE quantity that can distribute.

PDCCH of the prior art takies the deterministic process of symbolic number as shown in Figure 1, comprises the steps:

Step 101: obtain cell physical layer identifiers by cell search process;

Step 102: determine the actual resource location taken of PCFICH channel;

Step 103: obtain PHICH resource information by system information broadcast, and then determine resource location shared by PHICH, system bandwidth, antenna port number;

After the resource distribution of step 104:PHICH is determined, indicate PDCCH channel resource number in decision systems by the data of the PCFICH of static configuration in advance.

PCFICH channel instruction PDCCH takies symbolic number, determines PDCCH and PDSCH and takies symbol space division.By static configuration PCFICH value in prior art, realize PDCCH and PDSCH time-domain resource to control, due to the uncertainty of system user number, number of services and business data transmission characteristic, this simply extensive resource dividing method can not the load of adaptive system and the dynamic change of traffic performance, causes the limited or Zone satisfaction of power system capacity to decline.

Summary of the invention

The invention provides a kind of method that self-adaptative adjustment PDCCH takies symbolic number, reasonable adjusting PDCCH can be realized and take symbolic number, Zone satisfaction can be improved, improve power system capacity.

A kind of self-adaptative adjustment PDCCH that the embodiment of the present invention provides takies the method for symbolic number, it is characterized in that, comprises the steps:

The satisfaction of Zone in A, periodically detection a period of time;

B, judge that whether the satisfaction of Zone is lower than the first threshold value, if so, perform step C, otherwise, return execution steps A;

The occupancy of C, calculation plot bandwidth resources, judges that whether the occupancy of cell bandwidth resources is lower than the second threshold value, if so, performs step D, otherwise performs step e;

D, increase PDCCH take symbolic number, and return steps A;

The number of users of E, acquisition current system, and judge that whether number of users is lower than the 3rd threshold value, if so, performs step F, otherwise returns steps A;

F, minimizing PDCCH take symbolic number and return steps A.

Preferably, steps A comprises:

A1, judge whether sense cycle timer expired, if so, perform steps A 2, otherwise continue to perform steps A 1;

In A2, calculation plot, business i is at the satisfaction Sat (i, t) of present sub-frame t to network offering services, and span is [0 ~ 1];

A3, judge whether i equals the current total business number N of system _services, if so, perform steps A 4, otherwise, make i=i+1, and return steps A 2;

A4, according to formula $\mathrm{Sat}\left(\stackrel{\‾}{t}\right)=\frac{\underset{t=\stackrel{\‾}{t}-N_{\mathrm{TTI}}}{\overset{\stackrel{\‾}{t}}{\mathrm{\Σ}}}\underset{i=1}{\overset{N_{\mathrm{service}}}{\mathrm{\Σ}}}\mathrm{Sat}(i,t)}{N_{\mathrm{TTI}}*N_{\mathrm{service}}}*100\%$ The satisfaction of calculation plot business, wherein, N _tTIfor the duration of sense cycle timer measured with number of sub frames.

Preferably, if business i ensures bit rate type GBR traffic for accumulative high, then business i is business actual transfer rate at present sub-frame t to the satisfaction Sat (i, t) of network offering services with the GBR speed GBR of application _iratio $\mathrm{Sat}(i,t)=\frac{\stackrel{\‾}{R}(i,t)}{{\mathrm{GBR}}_i}.$

Preferably, if business i is non-GBR traffic, then according to formula $\mathrm{Sat}(i,t)=\frac{\mathrm{Delay}\_{\mathrm{Timer}}_i-\mathrm{Timer}\_\mathrm{threshold}}{\mathrm{WT}(i,t)}$ Computing service i at the satisfaction Sat (i, t) of present sub-frame t to network offering services, wherein, Delay_Timer _ifor the wireless spread-spectrum technology control protocol layer delay requirement end to end that the grouped data delay budget PDB that the quality of service class mark QCI grade by logic channel i is corresponding converts, unit is millisecond; Timer_threshold is the time delay thresholding that non-GBR traffic allows at rlc layer, and unit is millisecond; WT (i, t) is that unit is millisecond by the stand-by period of the packet arrived at first to subframe t business i in downstream.

Preferably, described in step C, the occupancy of calculation plot bandwidth resources is: according to formula $P_{t\_\mathrm{use}}=\frac{\underset{t=\stackrel{\‾}{t}-N_{\mathrm{TTI}}}{\overset{\stackrel{\‾}{t}}{\mathrm{\Σ}}}{N}_{i,d\_\mathrm{use}}}{N_{\mathrm{TTI}}*N_{d\_\mathrm{total}}}*100\%$ The occupancy of calculation plot bandwidth resources, wherein: N _{i, d_use}represent the stock number of i-th TTI scheduling; N _{d_total}represent the descending stock number allowing scheduling.

Preferably, increase before PDCCH takies the step of symbolic number described in step D, comprise further: whether be maximum, if so, then take symbolic number to PDCCH and do not make an amendment, and return steps A if judging that the PDCCH of current configuration takies symbol numbers; If not, the step that described increase PDCCH takies symbolic number is performed.

Preferably, increase PDCCH described in step D to take symbolic number and be: the symbolic number taken by PDCCH adds 1.

Preferably, described maximum is 4.

Preferably, reduce before PDCCH takies the step of symbolic number described in step F, comprise further: whether be minimum value, if so, then take symbolic number to PDCCH and do not make an amendment, and return steps A if judging that the PDCCH of current configuration takies symbol numbers; If not, the step that described minimizing PDCCH takies symbolic number is performed.

Preferably, reduce PDCCH described in step e to take symbolic number and be: the symbolic number taken by PDCCH subtracts 1.

Preferably, described minimum value is 1.

The present invention program carrys out self-adaptative adjustment PDCCH take symbolic number by calculating current area business satisfaction and the occupancy of scheduling resource and the number of users of current access, and then improves the capacity of system and the satisfaction at line service, realizes system self-optimizing.

Accompanying drawing explanation

Fig. 1 determines in prior art that PDCCH takies the schematic flow sheet of symbolic number;

Fig. 2 is the method flow schematic diagram that the present invention proposes that self-adaptative adjustment PDCCH takies symbolic number.

Embodiment

The basic thought of the present invention program is by calculation plot business satisfaction and system bandwidth resources occupation rate, carrys out dynamic conditioning PDCCH resource size.

The present invention proposes self-adaptative adjustment PDCCH and takies the method flow of symbolic number as shown in Figure 2, comprises the steps:

Step 201: the satisfaction periodically detecting Zone in a period of time.

Step 202: judge that whether the satisfaction of Zone is lower than the first threshold value, if so, performs step 203, otherwise, return and perform step 201.

Step 203: the occupancy of calculation plot bandwidth resources.

Step 204: judge that whether the occupancy of cell bandwidth resources is lower than the second threshold value, if (illustrative system does not make full use of schedulable system resource), performs step 205, otherwise performs step 206.

Step 205: adjustment PDCCH takies symbolic number, increases schedulable business number, and returns step 201.

Step 206: the number of users obtaining current system, and judge that whether number of users is lower than the 3rd threshold value, if (illustrate that current system major part or whole customer services belong to accumulative high guarantee bit rate type (GBR, Guaranteed Bit Rate) business), perform step 207, otherwise return step 201.

Step 207: adjustment PDCCH takies symbolic number, increases Physical Downlink Shared Channel (PDSCH) resource that can dispatch, and returns step 201.

The above first threshold value and the second threshold value are simulation parameter value, are configured by the network optimization or planning personnel.3rd threshold value configures relevant to bandwidth of cell, and under concrete bandwidth, value adopts simulation parameter value, is configured by the network optimization or planning personnel.

Such scheme just gives adjustment PDCCH and takies the scheme of symbolic number, does not limit the mode of distributing PDCCH first and take symbolic number.If distribute PDCCH first to take symbolic number, can default configuration parameters be adopted, be configured by the network optimization or planning personnel.

The satisfaction method of the business that the present invention can realize by the scheduler module in base station and statistical system bandwidth resources occupation rate, realize PDCCH resource dynamic conditioning, effectively can improve in the satisfaction of line service and system bandwidth resources occupation rate, and there is the low advantage of implementation complexity.

For making the know-why of technical solution of the present invention, advantage and technique effect clearly, below by way of specific embodiment, the present invention program is further elaborated.

The embodiment of the present invention one provides a kind of implementation of satisfaction of calculation plot access service.Satisfaction Shi Dui community, community, to the overall merit of each business satisfaction, is the average of all business satisfactions in a period of time, and being that current system does not reach the most effective index to community access service Satisfaction index, is that PDCCH resource plans prerequisite again.Zone satisfaction is the average of current all business satisfactions in community, and it is defined as follows:

$\mathrm{Sat}\left(\stackrel{\‾}{t}\right)=\frac{\underset{t=\stackrel{\‾}{t}-N_{\mathrm{TTI}}}{\overset{\stackrel{\‾}{t}}{\mathrm{\Σ}}}\underset{i=1}{\overset{N_{\mathrm{service}}}{\mathrm{\Σ}}}\mathrm{Sat}(i,t)}{N_{\mathrm{TTI}}*N_{\mathrm{service}}}*100\%---\left(1\right)$

Wherein, N _tTIfor the time granularity (cycle) of calculation plot satisfaction rate measured with number of sub frames, comprise N _tTIsubframe; N _servicesfor the current total business number of system; Sat (i, t) represents that business i is in the satisfaction of subframe t to network offering services, and span is [0 ~ 1].

Below provide a kind of embodiment of step 201:

Step 201-1, judge whether sense cycle timer expired, if so, perform step 201-2, otherwise continue to perform step 201-1;

In step 201-2, calculation plot, business i is at the satisfaction Sat (i, t) of present sub-frame t to network offering services, and span is [0 ~ 1];

Step 201-3, judge whether i equals the current total business number N of system _services, if so, perform step 201-4, otherwise, make i=i+1, and return step 201-2;

Step 201-4, satisfaction according to formula (1) calculation plot business, wherein, N _tTIfor the duration of sense cycle timer measured with number of sub frames.

Business i can have various definitions mode at the satisfaction Sat (i, t) of subframe t, below provides two examples:

For GBR traffic, business i is obtained by the ratio of the GBR speed of business actual transfer rate and application at the satisfaction Sat (i, t) of subframe t:

$\mathrm{Sat}(i,t)=\frac{\stackrel{\‾}{R}(i,t)}{{\mathrm{GBR}}_i}---\left(2\right)$

Wherein: for the radio interface rate (unit is bits per second (bps)) of t logic channel i; GBR _ifor the GBR of logic channel i.

For non-GBR traffic, obtained by the ratio of business QCI equivalent delay and propagation delay time:

$\mathrm{Sat}(i,t)=\frac{\mathrm{Delay}\_{\mathrm{Timer}}_i-\mathrm{Timer}\_\mathrm{threshold}}{\mathrm{WT}(i,t)}---\left(3\right)$

Wherein, Delay_Timer _ifor the quality of service class mark (QCI by logic channel i, QoS ClassIdentifier) grouped data delay budget (PDB corresponding to grade, Packet Delay Budget) the wireless spread-spectrum technology control protocol (RLC that converts, Radio Link Control) layer delay requirement end to end, unit is millisecond (ms); Timer_threshold is the time delay thresholding that non-GBR traffic allows at rlc layer, and unit is millisecond (ms); WT (i, t) is that unit is millisecond (ms) by the stand-by period of the packet arrived at first to subframe t business i in downstream.

Local resource occupancy refers to all scheduling resource amounts of business use of scheduling and the ratio of descending schedulable resource in a period of time, when local resource occupancy is less, illustrate that current system also has data carrying capabilities, but scheduler module can not dispatch more business, therefore need to regulate PDCCH to take symbol numbers to improve schedulable traffic carrying capacity; If system bandwidth resources occupation rate is larger, then obtain current online user number; If active user's number is fewer, then illustrates that current access user great majority belong to high accumulative GBR traffic, then reduce the symbol numbers that PDCCH takies.

The embodiment of the present invention provides a kind of definition of cell bandwidth resources occupation rate, as shown in formula (4):

$P_{t\_\mathrm{use}}=\frac{\underset{t=\stackrel{\‾}{t}-N_{\mathrm{TTI}}}{\overset{\stackrel{\‾}{t}}{\mathrm{\Σ}}}{N}_{i,d\_\mathrm{use}}}{N_{\mathrm{TTI}}*N_{d\_\mathrm{total}}}*100\%---\left(4\right)$

Wherein: N _{i, d_use}represent the stock number of i-th TTI scheduling; N _{d_total}the descending stock number allowing scheduling.

If system bandwidth resources occupation rate is lower than the second threshold value, then whether be maximum, if so, then take symbolic number to PDCCH and do not make an amendment, directly return step 201 if judging that the PDCCH of current configuration takies symbol numbers further; If not, then increase the number that PDCCH takies symbol, preferably, each increase symbol.Specify that the maximum that PDCCH takies symbol is 4 with bandwidth related protocol.

If system bandwidth resources occupation rate is greater than the second threshold value, then obtain current online user number, if active user's number is fewer, then illustrate that current access user great majority belong to accumulative high GBR traffic, then judge that current PDCCH takies symbolic number and whether reaches minimum value further, if reached, then symbolic number is taken to PDCCH and do not make an amendment, directly return step 201; If do not reached, then reduce the symbol numbers that PDCCH takies, preferably, each minimizing symbol.Bandwidth related protocol specifies that the minimum value that PDCCH takies symbol is 4.

The present invention carrys out self-adaptative adjustment PDCCH take symbolic number by calculating current area business satisfaction and the occupancy of scheduling resource and the number of users of current access, and then improves the capacity of system and the satisfaction at line service, realizes system self-optimizing.

The foregoing is only preferred embodiment of the present invention, not in order to limit the present invention, within the spirit and principles in the present invention all, any amendment made, equivalent replacement, improvement etc., all should be included within the scope of protection of the invention.

Claims (10)

1. self-adaptative adjustment physical downlink control channel PDCCH takies a method for symbolic number, it is characterized in that, comprises the steps:

The satisfaction of Zone in A, periodically detection a period of time; Specifically comprise:

A1, judge whether sense cycle timer expired, if so, perform steps A 2, otherwise continue to perform steps A 1;

In A2, calculation plot, business i is at the satisfaction Sat (i, t) of present sub-frame t to network offering services, and span is [0 ~ 1];

A3, judge whether i equals the current total business number N of system _service, if so, perform steps A 4, otherwise, make i=i+1, and return steps A 2;

A4, according to formula the satisfaction of calculation plot business, wherein, N _tTIfor the duration of sense cycle timer measured with number of sub frames;

B, judge that whether the satisfaction of Zone is lower than the first threshold value, if so, perform step C, otherwise, return execution steps A;

The occupancy of C, calculation plot bandwidth resources, judges that whether the occupancy of cell bandwidth resources is lower than the second threshold value, if so, performs step D, otherwise performs step e;

D, increase PDCCH take symbolic number, and return steps A;

The number of users of E, acquisition current system, and judge that whether number of users is lower than the 3rd threshold value, if so, performs step F, otherwise returns steps A;

F, minimizing PDCCH take symbolic number and return steps A.

2. method according to claim 1, is characterized in that, if business i ensures bit rate type GBR traffic for accumulative high, then business i is business actual transfer rate at present sub-frame t to the satisfaction Sat (i, t) of network offering services with the GBR speed GBR of application _iratio

3. method according to claim 1, is characterized in that, if business i is non-GBR traffic, then according to formula computing service i at the satisfaction Sat (i, t) of present sub-frame t to network offering services, wherein, Delay_Timer _ifor the wireless spread-spectrum technology control protocol layer delay requirement end to end that the grouped data delay budget PDB that the quality of service class mark QCI grade by logic channel i is corresponding converts, unit is millisecond; Timer_threshold is the time delay thresholding that non-GBR traffic allows at rlc layer, and unit is millisecond; WT (i, t) is that unit is millisecond by the stand-by period of the packet arrived at first to subframe t business i in downstream.

4. method according to claim 1, is characterized in that, described in step C, the occupancy of calculation plot bandwidth resources is: according to formula the occupancy of calculation plot bandwidth resources, wherein: N _{i, d_use}represent the stock number of i-th TTI scheduling; N _{d_total}represent the descending stock number allowing scheduling.

5. method according to claim 1, is characterized in that, increases before PDCCH takies the step of symbolic number described in step D, comprise further: whether judge that the PDCCH of current configuration takies symbol numbers is maximum, if so, then take symbolic number to PDCCH not make an amendment, and return steps A; If not, the step that described increase PDCCH takies symbolic number is performed.

6. method according to claim 5, is characterized in that, increases PDCCH and takies symbolic number and be: the symbolic number taken by PDCCH adds 1 described in step D.

7. method according to claim 5, is characterized in that, described maximum is 4.

8. method according to claim 1, is characterized in that, reduces before PDCCH takies the step of symbolic number described in step F, comprise further: whether judge that the PDCCH of current configuration takies symbol numbers is minimum value, if so, then take symbolic number to PDCCH not make an amendment, and return steps A; If not, the step that described minimizing PDCCH takies symbolic number is performed.

9. method according to claim 8, is characterized in that, reduces PDCCH and takies symbolic number and be: the symbolic number taken by PDCCH subtracts 1 described in step e.

10. method according to claim 9, is characterized in that, described minimum value is 1.