CN1479464A - Self interference admission control method of CDMA system - Google Patents

Abstract

Based on CDMA self-interference principle, building mathematic model of mixed service obtains solution of upward received power after power rising of each service so as to calculate out upward received total power of system. Comparing the total power value with admission control threshold determines whether the preset calling request can be accepted. The method is not dependent on the measured value for system upward total received power reported from base station so as to prevent inference of measured error. Moreover, the method is very suitable to condition, in which ratio of signal to noise is changed in real time.

Description

The self interference admission control method of code division multiple access system

(1) technical field

The present invention relates to a kind of self interference admission control method of code division multiple access system, refer in particular to the acceptance controlling method under a kind of Wideband Code Division Multiple Access (WCDMA) (WCDMA:Wide-band Code Division Multiple Access) system mixed service situation, belong to 3-G (Generation Three mobile communication system) (3G) field.

(2) background technology

The mobile communication development in recent years is very rapid, has become a very important part among the human lives between a few years.Be accompanied by the fast development of Internet technology, people have greatly promoted the development of 3-G (Generation Three mobile communication system) (IMT-2000) to craving for of mobile Internet.The WCDMA technology is the mainstream technology of 3-G (Generation Three mobile communication system), because the needs that mobile Internet access etc. are professional, the WCDMA system compares with gsm system and second generation mobile communication system, the loaded service type is single voice service no longer just, but mixed service, its type of service is divided into level Four by professional service quality (QoS:Quality of Service): session level (conversational class, as telephone service, IP talk business etc.), stream level (streaming class, as video or voice data), mutual level (interactive class, browse as online, server inserts, database access etc.) and the backstage level (background class is as backstage distribution E-mail, file in download, receive measurement report etc.).Because the access of mixed service, make admittance control, the duty control method of WCDMA system can not continue to use single method when professional again.

Adopt hard capacity based on time-multiplexed gsm system, the characterization parameter of its capacity is the number of channel, and promptly timeslot number in case all time slots are all taken, then can not insert new user again.

IS-95 system (second generation CDMA mobile communication systems) though identical with GSM on type of service, different fully with GSM technically, employing be the code division multiple access principle, its channel with the sign indicating number sequence distinguish.The user at one time, same frequency range work, therefore IS-95 (CDMA) system is a self-interference system, and all users in the system disturb each other each other, so the capacity of system and interference is big or small closely related, closely related with QoS of survice, capacity is soft.QoS of survice comprises that mainly professional information source speed, the error rate require and delay requirement, such as satisfying under certain QoS condition, at most approximately can insert 100 voice users, if but insert a speech on this basis again and also be fine, only be that speech quality has reduction slightly.Therefore, the sign of IS-95 power system capacity can not adopt number of channel explanation simply, also should be relevant with the QoS of business need.

3-G (Generation Three mobile communication system) has also adopted CDMA (Code Division Multiple Access) mostly, but is that the loaded service type is different with the difference of second generation IS-95 system maximum, and its business is the mixed service that voice service and Packet data service are laid equal stress on, and this mentioned at preamble.Since the third generation system bearing mixed service of rate-compatible, traffic performance is compared much complicated with single voice service, the behavioral trait of miscellaneous service in system is different greatly, thereby the transmission technology of third generation code division multiple access system and system control method and IS-95 system be very different, and can not adopt the number of channel simply especially to the evaluation of power system capacity.3-G (Generation Three mobile communication system) also has the soft capacity characteristic, and its capacity is relevant with professional desired service quality, and when the radio link quality that requires descended, it is big that capacity becomes, otherwise then diminish.And, also will be owing to the variation of third generation system business type, different with to delay requirement of the priority of miscellaneous service, data rate, feasible evaluation and admittance control procedure to power system capacity also becomes complicated more, to determining and system's acceptance controlling method of capacity characterization parameter, at present do not see that in disclosed publication clear and definite unified standard is arranged yet, even the 3GPP of 3-G (Generation Three mobile communication system) standardization body do not work out unified standard yet, and system control method is that each company serves as basis development voluntarily with the 3GPP relevant criterion.Therefore, we can say, at the acceptance controlling method of the mixed service of 3-G (Generation Three mobile communication system), still blank field almost at present.

Adopt the 3-G (Generation Three mobile communication system) of CDMA (Code Division Multiple Access), owing to distinguish the incomplete orthogonality of each user's spreading code, caused this system to become a self-interference system, perhaps be interference limiting system, any one user in the system other users relatively is an interference source.Therefore, when user in the system constantly increases, equal to disturb continuous increase, in order to guarantee the needed QoS of miscellaneous service, will be by the continuous transmitting power that increases separately of closed power controlling mechanism, promptly not only current new access user's transmitting power is bigger than the transmitting power of original same line of business user in the system, and all original users' that inserted in the system transmitting power is also wanted corresponding increase, the power that makes all same line of business users in the system arrive the base station receiving terminal at last all will be increased to identical value, power ramp phenomenon that Here it is.This is a process from low balance point to high balance point, and system is exactly stable during this process convergence, otherwise is exactly unsettled.Like this, after user in the system is increased to certain degree, can cause that the unexpected avalanche type of power rises, even only increase a user this moment, the needed transmitting power of all users all needs to increase a lot, the total up reception gross power of system also increases a lot thereupon, received power will exceed the receiving circuit non-linear domain and lose efficacy, the professional error rate sharply descends, system just is in paralysis or collapse state, illustrates that the business of current access can not have been admitted by system, must will predict before this situation occurring, and carry out control, to guarantee system stable operation.This shows that the essence of decision capacity of CDMA system is the up reception gross power of system, do not admit the control thresholding, just can insert new user as long as the up reception gross power of system also exceeds.Therefore, predict that just can the criterion that can be admitted as current business with this predicted power determine whether system admits this business if can receive gross power to the business of the current call request system uplink after access.

In contrast to this, the method for present predictive call traffic load increment is based on the method for throughput.Specifically with reference to the works of people such as the Harri Holma of Nokia Telecommunications with reference to the 3GPP protocol specification---" WCDMA of UMTS---wireless access of 3G (Third Generation) Moblie ".The method of present used prediction traffic load increment is not a core with power, the load increment of predictive call business is not directly to launch or the received power increment, more do not consider the influence that multiple access disturbs, not corresponding with real system, both impracticable, inaccurate again, cause the false judgment of admitting control easily.In disclosed patent, also there is not acceptance controlling method at mixed service and non-symmetrical service.Have only some relevant patents, as United States Patent (USP) (patent No. is US5687171) " method and apparatus that distributes wireless channel in the cdma system " is immediate method, and this method is based on and measures base station received signal intensity, calculates the surplus, the estimation that allow and distributes a wireless channel when calling out required power, surplus greater than power demand.This method is the acceptance controlling method of the single business of the typical second generation, symmetrical service, and only measures up base station received signal intensity; These methods are not considered the power ramp amount when calculating the call business power demand, do not consider that more non-symmetrical service admits the problem of control respectively at uplink and downlink, because the measurements and calculations of uplink and downlink load surplus method is different, do not consider particularity and professional priority that non-real-time service is admitted, promptly not with the principal element of QoS of survice as admittance control, can not satisfy the diversified requirement of third generation system mixed service fully, not consider that more the mixed service Combination Optimized consequently reaches the problem of efficient operation.

Characteristics and power ramp principle based on above 3-G (Generation Three mobile communication system) business self the present invention proposes the mixed service access control method based on self-interference, the admittance control problem when solving the mixed service access.

(3) summary of the invention

The objective of the invention is to propose a kind of self interference admission control method of code division multiple access system, be meant the Forecasting Methodology of up reception gross power when a kind of mixed service inserts, can be admitted by system to determine the business that current request inserts according to this predicted power, reach the effect that improves running efficiency of system, reduces call blocking rate and cutting off rate.

The present invention is based on the self-interference principle of code division multiple access system, set up the Mathematical Modeling of mixed service, solve the up received power of miscellaneous service after power ramp, thereby the up reception gross power of computing system, relatively this total power value and admittance control thresholding judge that can the business of current call request be admitted.

The object of the present invention is achieved like this: a kind of self interference admission control method of code division multiple access system, and the step of wherein said control method comprises:

The first step: from the QoS (service quality) of call business, extract professional information source speed R, required signal-to-noise ratio E _b/ N ₀Value;

Second step: according to the self-interference principle, the type of service that existing type of service and current request in the system are inserted is set up the math equation of the relation of up received power after the power ramp and interference respectively, i.e. the math equation of all interference powers in such professional up received power that arrives the base station and the system after the current request service access;

The 3rd step: the separate equation that simultaneous step the second was set up in the step, form Nonlinear System of Equations, adopt numerical method to find the solution this equation group, obtain the up received power value of miscellaneous service after power ramp;

The 4th step: set up the math equation that system uplink after the power ramp receives the relation of the quantity of gross power and miscellaneous service and corresponding up received power value thereof;

The 5th goes on foot: the equation that the up received power value substitution step the of the miscellaneous service that solves during step the three is gone on foot was set up in four steps can obtain the system uplink reception gross power P after current business inserts _Total

The 6th step: the system uplink after relatively current business inserts receives gross power P _TotalAdmit control thresholding P with system _ThIf, P _Total＜P _ThThen admit, radio resource controller RRC (Radio Resource Control) returns the admittance signaling, enters for the 7th step; Otherwise, if P _Total＞P _Th, illustrating that then the access of current call request will cause system to exceed the admittance control thresholding of the required assurance of steady operational status, system will be in overload.Therefore, can not admit current call request, carry out call drop or block processing, get back to the step first step, wait for the arrival of next time calling out;

The 7th step: if the Nonlinear System of Equations that step the was set up in three steps has do not separate, illustrate that then avalanche type power ramp phenomenon will appear in the admittance of current business, it is infinitely great that system uplink receives gross power, and system will collapse.Therefore, system excludes this call request, carries out call drop or blocks processing, gets back to the step first step and waits for the arrival of next time calling out;

The 8th step: assigned code resource;

The 9th step: revise the sign indicating number resource status table, return the step first step.

Effect of the present invention is: the mixed service access control method based on the code division multiple access system of self-interference model that the present invention proposes has following beneficial effect:

1) the capacity characterization parameter of capacity of CDMA system has been proposed;

Admittance control problem when 2) having solved mixed service;

3) result of calculation does not rely on the measured value that system uplink that the base station reports receives gross power, has avoided measuring the inaccurate influence that brings to system;

4) flexibility is good, is fit to signal to noise ratio E _b/ N ₀The situation of real-time change.In the system of reality, because the variation of factors such as physical geography will obtain satisfied service quality, signal to noise ratio E _b/ N ₀May need real-time change.Mixed service model based on self-interference has been considered E from model _b/ N ₀Influencing factor, no matter how it to change, as long as can provide concrete value, the system uplink that just can solve this moment receives the up received power value of the miscellaneous service arrival base station after total power value and the power ramp.Therefore, this model has extraordinary flexibility and adaptability, and this is very practical for changing various mobile communication environment;

5) exactly during the predictive call service access to the influence degree of system, improved running efficiency of system and resource utilization ratio, guaranteed service quality.

In sum, the present invention has proposed broadband CDMA system first based on self-interference model mix service admission control method, this method is from the self-interference characteristic of broadband CDMA system, self-interference model when having set up mixed service, the up reception gross power of system after the call request service access that can calculate to a nicety, carry out admission judgment, and can also obtain simultaneously after the power ramp the up received power of miscellaneous service in the system.This method does not rely on the measured value that system uplink that the base station reports receives gross power, has avoided influence of measurement error.In addition, this method also is highly suitable for signal to noise ratio E _b/ N ₀The situation of real-time change all has practical value to system design and system stable operation.

For further specifying above-mentioned purpose of the present invention, design feature and effect, the present invention is described in detail below with reference to accompanying drawing.

(4) description of drawings

Fig. 1 is the program circuit that adopts direct solution by iterative method Nonlinear System of Equations (1);

Fig. 2 is the max value of error of all both members in the Nonlinear System of Equations (1)---an iterations curve;

Fig. 3 is that amplify the part of Fig. 2.

(5) embodiment

Functional module of the present invention is embodied in the radio network controller (RNC) (Radio NetworkControler) with software, controls and manage many base stations (sub-district) by RNC.In conjunction with step of the present invention, above method is described in further detail with an embodiment:

The first step: at first from the request of call business (user's) RAB (RAB) with the Quality of Service parameter, extract information source speed R, the required signal-to-noise ratio E of call business _b/ N ₀Value, priority level and calling party's identify label (ID) value, signal to noise ratio is according to the difference of data service and difference, example: the qos parameter of 8kbps, 12.2kbps speech is different with data services such as 64kbps, 144kbps, 384kbps, the average signal-to-noise ratio of speech requires to be about 5dB, corresponding Block Error Rate (BLER) is one of percentage, and the average signal-to-noise ratio of data such as 64kbps, 144kbps, 384kbps requires to be 3.5dB;

Second step:, set up the self-interference model according to the self-interference principle.For any user, other users that inserted in the system can regard interference as, and in addition, the user of neighbor cell disturbs, and it is generally acknowledged that neighbor cell interference is 55% of this area interference.According to self-interference and power ramp principle, after the current request service access, reach satisfied QoS, the interference power that the up received power of its arrival base station must be able to be resisted its all interference sources promptly is greater than or equal to all interference power sums.In the system all of comprising these interference sources have inserted the user, the neighbor cell user disturbs and background noise disturbs.

The business that has inserted in the supposing the system has 8kbps, 12.2kbps, and 64kbps, 144kbps and 384kbps, current request access service are a 8kbps voice service, it is as follows that 8kbps business after the power ramp is set up equation: $p_8=101g\underset{T}{\mathrm{\Σ}}({10}^{0.1B_g}+1.55N_T{10}^{0.1p_T})-P_{G8}+{\left(\frac{E_b}{N_0}\right)}_8\mathrm{dBm}$

Wherein,

T is a type of service, T=8kbps, 12.2kbps, 64kbps, 144kbps, 384kbps;

The rest may be inferred for the business of other types:

That is: the business that has inserted in the supposing the system has x1kbps, x2kbps, x3kbps ... xnkbps, current request access service are the business of an xakbps, wherein a=1,2,3 ... n, it is as follows that xakbps business after the power ramp is set up equation: $p_{\mathrm{xa}}=101g\underset{T}{\mathrm{\Σ}}({10}^{0.1B_g}+1.55N_T{10}^{0.1p_T})-P_{\mathrm{Gxa}}+{\left(\frac{E_b}{N_0}\right)}_{\mathrm{xa}}\mathrm{dBm}---\left(1\right)$

Wherein,

T is a type of service, T=x1kbps, x2kbps, x3kbps ... xnkbps;

Bg (dBm) is a self noise power, B _g=101g (kT ₀B), T wherein ₀Being environment absolute temperature (K) that k is a Boltzmann constant, is 1.38 * 10 ^-23Joule/K, B are communication bandwidth (Hz), and the communication bandwidth of WCDMA system is 5MHz; Get B under the normal temperature (27 degrees centigrade) _g=-103.157dBm;

Coefficient 1.55 is for considering the full situation of peripheral cell, and promptly peripheral cell disturbs and is 55% of this area interference;

p _X1, p _X2, p _X3P _XnBe respectively and insert current xakbps business and cause after the power ramp x1kbps, x2kbps, x3kbps in the system ... the up received power of xnkbps business, i.e. P in the aforesaid equation (1) _T, dimension is dBm;

N _X1, N _X2, N _X3N _XnBe positive integer, represent the quantity of the corresponding service that existed in the system before the current xakbps service access respectively, i.e. N in the aforesaid equation (1) _T, dimensionless;

P _Gx1, P _Gx2, P _Gx3P _GxnBe respectively the processing gain of corresponding service, $P_{\mathrm{GT}}=101g\left(\frac{3840\mathrm{kcps}}{R_T}\right)\mathrm{dB},$ R _TBe service rate, dimension is kbps.Processing gain has comprised spreading gain and coding gain; ${\left(\frac{E_b}{N_0}\right)}_{x1},{\left(\frac{E_b}{N_0}\right)}_{x2},{\left(\frac{E_b}{N_0}\right)}_{x3}\·\·\·\·\·\·{\left(\frac{E_b}{N_0}\right)}_{\mathrm{xn}}$ Be respectively the average signal-to-noise ratio of corresponding service QoS correspondence, value is same as above.

The 3rd step: each equation that simultaneous was set up in second step becomes Nonlinear System of Equations, and adopts this Nonlinear System of Equations of numerical value solution by iterative method, can solve miscellaneous service arrives the base station after power ramp up received power value P _T, T=x1kbps, x2kbps, x3kbps ... xnkbps.

The 4th step: set up the mathematical description equation that system uplink after the power ramp receives the relation of the quantity of gross power and miscellaneous service and corresponding up received power value thereof.At this moment, the total up received power of system should be the up received power sum of all business that inserted in this sub-district.

Still the business that has inserted in the supposing the system has 8kbps, and 12.2kbps, 64kbps, 144kbps and 384kbps, current request access service are that a 8kbps voice service is an example: $P_{\mathrm{total}}=101g[{10}^{{0.1B}_g}+{(N_8+1)10}^{{0.1p}_g}+N_{12.2}{10}^{{0.1p}_{12.2}}+N_{64}{10}^{0.1p_{64}}$ $+N_{144}{10}^{{0.1p}_{144}}+N_{384}{10}^{0.1p_{\text{384}}}]\mathrm{dBm}$

The rest may be inferred for the business of other types:

That is: the business that has still inserted in the supposing the system has x1kbps, x2kbps, x3kbps ... xnkbps, the current request access service is the business of an xakbps, a=1,2,3 wherein ... n, at this moment, the total up received power of system should be the up received power sum of all business that inserted in this sub-district: $P_{\mathrm{total}}=101g[{10}^{{0.1B}_g}+{10}^{{0.1p}_{\mathrm{xa}}}+N_{x1}{10}^{{0.1p}_{x1}}+N_{x2}{10}^{0.1p_{x2}}---\left(2\right)$ $+N_{x3}{10}^{{0.1p}_{x3}}+......+N_{\mathrm{xn}}{10}^{0.1p_{\mathrm{xn}}}]\mathrm{dBm}$

The 5th step: compare P _TotalAdmit control thresholding P with system _ThIf, P _Total＜P _ThThen admit, RRC returns the admittance signaling, enters for the 7th step; Otherwise, if P _Total＞P _Th, illustrating that then the access of current call request will cause system to exceed the admittance control thresholding of the required assurance of steady operational status, system will be in overload.Therefore, can not admit current call request, carry out call drop or block processing, get back to the first step and wait for the arrival of next time calling out;

The 6th step: if the Nonlinear System of Equations of setting up in the 3rd step has do not separate, illustrate that then avalanche type power ramp phenomenon will appear in the admittance of current business, it is infinitely great that system uplink receives gross power, and system will collapse.Therefore, system excludes this call request, carries out call drop or blocks processing, gets back to the first step and waits for the arrival of next time calling out;

The 7th step: start sign indicating number resource allocation subprocess;

The 8th step: revise the sign indicating number resource status table, return the first step.

The present invention is further illustrated below in conjunction with accompanying drawing:

The process of the described Nonlinear System of Equations of the described solution by iterative method of Fig. 1 is (still x1kbps is arranged is 8kbps to the business that has inserted in the supposing the system, and x2kbps is 12.2kbps, and x3kbps is 64kbps, and x4kbps is that 144kbps and x5kbps are 384kbps):

At first make iterations k=-0;

Set iterative initial value p ₈ ^(k), p _12.2 ^(k), p ₆₄ ^(k), p ₁₄₄ ^(k), p ₃₈₄ ^(k)

With this initial value substitution equation (1), calculate p ₈ ^(k+1), p _12.2 ^(k+1), p ₆₄ ^(k+1), p ₁₄₄ ^(k+1), p ₃₈₄ ^(k+1)

Calculate twice iteration in front and back absolute value Diff of difference as a result again _T=| P _T ^(k+1)-P _T ^(k)|, T=8,12.2,64,144,384, find out amount J=max{Diff maximum in the difference ₈, Diff _12.2, Diff ₆₄, Diff ₁₄₄, Diff ₃₈₄;

If J satisfies given computational accuracy, then iteration stops, and current iteration gained result is solution of equations;

If J does not satisfy given computational accuracy, need current iteration substitution formula as a result (1) is carried out next iteration, calculate p ₈ ^(k+2), p _12.2 ^(k+2), p ₆₄ ^(k+2), p ₁₄₄ ^(k+2), p ₃₈₄ ^(k+2), go on according to this, if, then illustrating equation group (1) in given precision, separates iteration convergence, with solution of equations substitution formula (2), the gained system uplink receives gross power P _TotalIf, then admit current call request, if P less than admitting the control thresholding _TotalGreater than admitting the control thresholding, though then not collapse of system's this moment has been in saturation condition, current call request can not be admitted;

If the maximum that iterations surpass to be set allows iterations, iteration still not have to restrain, and thinks then that equation group does not have to separate, and the access of current call request will cause system crash, can not be admitted.The general value of computational accuracy be one thousandth to ten ten thousand/, can satisfy application request; The maximum iterations that allows is below 3000 times, and general convergence rate is very fast, well below maximum, remains on computing time in the scope of real system permission.

The rest may be inferred for the business of other types, and (business that has inserted in the system has x1kbps, 2kbps, x3kbps ... xnkbps):

At first make iterations k=-0;

Set iterative initial value p _X1 ^(k), p _X2 ^(k), p _X3 ^(k)P _Xn ^(k)

With this initial value substitution equation (1), calculate p _X1 ^(k+1), p _X2 ^(k+1), p _X3 ^(k+1)P _Xn ^(k+1)

Calculate twice iteration in front and back absolute value Diff of difference as a result again _T=| P _T ^(k+1)-P _T ^(k)|, T=x1, x2, x3 ... xn finds out amount J=max{Diff maximum in the difference _X1, Diff _X2, Diff _X3Diff _Xn;

If J satisfies given computational accuracy, then iteration stops, and current iteration gained result is solution of equations;

If J does not satisfy given computational accuracy, need current iteration substitution formula as a result (1) is carried out next iteration, calculate p _X1 ^(k+2), p _X2 ^(k+2), p _X3 ^(k+2)P _Xn ^(k+2), go on according to this, if, then illustrating equation group (1) in given precision, separates iteration convergence, with solution of equations substitution formula (2), the gained system uplink receives gross power P _TotalIf, then admit current call request, if P less than admitting the control thresholding _TotalGreater than admitting the control thresholding, though then not collapse of system's this moment has been in saturation condition, current call request can not be admitted;

If the maximum that iterations surpass to be set allows iterations, iteration still not have to restrain, and thinks then that equation group does not have to separate, and the access of current call request will cause system crash, can not be admitted.The general value of computational accuracy be one thousandth to ten ten thousand/, can satisfy application request; The maximum iterations that allows is below 3000 times, and general convergence rate is very fast, well below maximum, remains on computing time in the scope of real system permission.

Curve representation among Fig. 2 be iterative equation group (1) time, the trend that the maximum value J of each both members difference of equation group in each time iterative process (1) changes with iterations, it has described the convergence of iterative process, illustrated that the iterative solution method that adopts restrains, and has robustness herein.

Fig. 3 is that amplify the part of Fig. 2, mainly observes difference J and no longer obviously descends with the iterations increase.

Core algorithm of the present invention is the foundation of system's self-interference Mathematical Modeling when receiving gross power as the thought of capacity of CDMA system deliberated index and mixed service with system uplink.

The protected scope of the present invention is the self-interference model of CDMA mobile communication systems and admits control that system loading estimates that range of application comprises whole moving communicating field.

Certainly, those of ordinary skill in the art will be appreciated that, above embodiment is used for illustrating the present invention, and be not to be used as limitation of the invention, as long as in connotation scope of the present invention, all will drop in the scope of claims of the present invention variation, the modification of the above embodiment.

Claims (7)

1, a kind of self interference admission control method of code division multiple access system is characterized in that described control method comprises:

The first step: from the QoS (service quality) of call business, extract professional information source speed R, required signal-to-noise ratio E _b/ N ₀Value;

Second step: according to the self-interference principle, the type of service that existing type of service and current request in the system are inserted is set up the math equation of the relation of up received power after the power ramp and interference respectively, i.e. the math equation of all interference powers in such professional up received power that arrives the base station and the system after the current request service access;

The 3rd step: the separate equation that simultaneous step the second was set up in the step, form Nonlinear System of Equations, adopt numerical method to find the solution this equation group, obtain the up received power value of miscellaneous service after power ramp;

The 4th step: set up the math equation that system uplink after the power ramp receives the relation of the quantity of gross power and miscellaneous service and corresponding up received power value thereof;

The 5th goes on foot: the equation that the up received power value substitution step the of the miscellaneous service that solves during step the three is gone on foot was set up in four steps can obtain the system uplink reception gross power P after current business inserts _Total

The 6th step: the system uplink after relatively current business inserts receives gross power P _TotalAdmit control thresholding P with system _ThIf, P _Total＜P _ThThen admit, RRC returns the admittance signaling, enters for the 7th step; Otherwise, if P _Total＞P _Th, illustrating that then the access of current call request will cause system to exceed the admittance control thresholding of the required assurance of steady operational status, system will be in overload, therefore, can not admit current call request, carry out call drop or block processing, get back to the step first step, wait for the arrival of next time calling out;

The 7th step: if the Nonlinear System of Equations that step the was set up in three steps has do not separate, illustrate that then avalanche type power ramp phenomenon will appear in the admittance of current business, it is infinitely great that system uplink receives gross power, and system will collapse.Therefore, system excludes this call request, carries out call drop or blocks processing, gets back to the step first step and waits for the arrival of next time calling out;

The 8th step: assigned code resource;

The 9th step: revise the sign indicating number resource status table, return the step first step.

2, the self interference admission control method of a kind of code division multiple access system as claimed in claim 1, it is characterized in that after the current request service access in described second step that (business that has inserted in the system has x1kbps for the mathematical equation of all interference powers in such professional up received power that arrives the base station and the system, x2kbps, x3kbps ... xnkbps, the current request access service is the business of an xakbps, a=1,2,3 wherein ... n sets up equation to xakbps business after the power ramp) as follows: $p_{\mathrm{xa}}=101g\underset{T}{\mathrm{\Σ}}({10}^{0.1B_g}+1.55N_T{10}^{0.1P_T})-P_{\mathrm{Gxa}}+{\left(\frac{E_b}{N_0}\right)}_{\mathrm{xa}}\mathrm{dBm}---\left(1\right)$

Wherein,

T is a type of service, T=x1kbps, x2kbps, x3kbps ... xnkbps;

B _g(dBm) be white noise power, B _g=101g (kT ₀B), T wherein ₀Being environment absolute temperature (K) that k is a Boltzmann constant, is 1.38 * 10 ^-23Joule/K, B are communication bandwidth (Hz), and the communication bandwidth of WCDMA system is 5MHz; Get B under the normal temperature (27 degrees centigrade) _g=-103.157dBm;

Coefficient 1.55 is for considering the full situation of peripheral cell, and promptly peripheral cell disturbs and is 55% of this area interference;

p _X1, p _X2, p _X3P _XnBe respectively and insert current xakbps business and cause after the power ramp x1kbps, x2kbps, x3kbps in the system ... the up received power of xnkbps business, i.e. P in the aforesaid equation (1) _T, dimension is dBm;

N _X1, N _X2, N _X3N _XnBe positive integer, represent the quantity of the corresponding service that existed in the system before the current xakbps service access respectively, i.e. N in the aforesaid equation (1) _T, dimensionless;

P _Gx1, P _Gx2, P _Gx3P _GxnBe respectively the processing gain of corresponding service, $P_{\mathrm{GT}}=101g\left(\frac{3840\mathrm{kcps}}{R_T}\right)$ DB, R _TBe service rate, dimension is kbps.Processing gain has comprised spreading gain and coding gain; ${\left(\frac{E_b}{N_0}\right)}_{x1},{\left(\frac{E_b}{N_0}\right)}_{x2},{\left(\frac{E_b}{N_0}\right)}_{x3}\·\·\·\·\·\·{\left(\frac{E_b}{N_0}\right)}_{\mathrm{xn}}$ Be respectively the average signal-to-noise ratio of corresponding service QoS correspondence.

3, the self interference admission control method of a kind of code division multiple access system as claimed in claim 1, it is characterized in that employing numerical method in described the 3rd step finds the solution this equation group and be meant with numerical value solution by iterative method described Nonlinear System of Equations, can solve miscellaneous service arrives the base station after power ramp up received power value P _T, at this, establish T=x1kbps, x2kbps, x3kbps ... xnkbps.

4, the self interference admission control method of a kind of code division multiple access system as claimed in claim 1, it is characterized in that the described the 4th, the mathematical description equation that system uplink after the power ramp receives the relation of the quantity of gross power and miscellaneous service and corresponding up received power value thereof set up in five steps is that the total up received power of system should (business that has inserted in the system has x1kbps for the up received power sum of all business that inserted in this sub-district, x2kbps, x3kbps ... xnkbps, the current request access service is the business of an xakbps, wherein a=1,2,3 ... n): $P_{\mathrm{total}}=101g[{10}^{{0.1B}_g}+{10}^{{0.1p}_{\mathrm{xa}}}+N_{x1}{10}^{{0.1p}_{x1}}+N_{x2}{10}^{0.1p_{x2}}$ $+N_{x3}{10}^{{0.1p}_{x3}}+......+N_{\mathrm{xn}}{10}^{0.1p_{\mathrm{xn}}}]\mathrm{dBm}---\left(2\right)$

5, the self interference admission control method of a kind of code division multiple access system as claimed in claim 3, the process that it is characterized in that the described Nonlinear System of Equations of described solution by iterative method is that (business that has inserted in the system has x1kbps, x2kbps, x3kbps ... xnkbps):

At first make iterations k=0;

Set iterative initial value p _X1 ^(k), p _X2 ^(k), p _X3 ^(k)P _Xn ^(k)

With the described equation group of this initial value substitution (1), calculate p _X1 ^(k+1), p _X2 ^(k+1), p _X3 ^(k+1)P _Xn ^(k+1)

Calculate twice iteration in front and back absolute value Diff of difference as a result again _T=| P _T ^(k+1))-P _T ^(k)|, T=x1, x2, x3 ... xn finds out amount J=max{Diff maximum in the difference _X1, Diff _X2, Diff _X3Diff _Xn; If J satisfies given computational accuracy, then iteration stops, and current iteration gained result is solution of equations;

If J does not satisfy given computational accuracy, need current iteration substitution equation group as a result (1) is carried out next iteration, calculate p _X1 ^(k+2), p _X2 ^(k+2), p _X3 ^(k+2)P _Xn ^(k+2), go on according to this, if, then illustrating described equation group (1) in given precision, separates iteration convergence, with the described equation group of solution of equations substitution (2), the gained system uplink receives gross power P _TotalIf, then admit current call request, if P less than admitting the control thresholding _TotalGreater than admitting the control thresholding, though then not collapse of system's this moment has been in saturation condition, current call request can not be admitted.

6, the self interference admission control method of a kind of code division multiple access system as claimed in claim 5, it is characterized in that the general value of described computational accuracy be one thousandth to ten ten thousand/, can satisfy application request.

7, the self interference admission control method of a kind of code division multiple access system as claimed in claim 5 is characterized in that the maximum permission of described iterations below 3000 times, and general convergence rate is very fast, well below maximum.

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