CN100386974C - Method of automatic background noise update in CDMA system - Google Patents
Method of automatic background noise update in CDMA system Download PDFInfo
- Publication number
- CN100386974C CN100386974C CNB2005100246375A CN200510024637A CN100386974C CN 100386974 C CN100386974 C CN 100386974C CN B2005100246375 A CNB2005100246375 A CN B2005100246375A CN 200510024637 A CN200510024637 A CN 200510024637A CN 100386974 C CN100386974 C CN 100386974C
- Authority
- CN
- China
- Prior art keywords
- back noise
- upgrade
- noise
- division multiple
- multiple access
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Landscapes
- Mobile Radio Communication Systems (AREA)
Abstract
The present invention relates to a code division multiple access (CDMA) system and discloses a method for automatically updating background noise in the CDMA system. The present invention makes the arrangement of the background noise of the system accurate, and the system can update the background noise in a self adapting mode according to the variation of temperature and the interference of other cells; particularly when the system has a high load, the system can also updating the background noise in the self adapting mode and simultaneously provide strong burst interference resistance capability. In the present invention, the method for automatically updating background noise in the CDMA system not only obtains the background noise of the system according to up interference when the load of the system is low, but also calculates the background noise through the combination of the up interference and other correlation parameters, and computed results are output after filtered and smoothed.
Description
Technical field
The present invention relates to code division multiple access (Code Division Multiple Access is called for short " CDMA ") system, particularly control relevant parameter acquiring with load in the cdma system.
Background technology
Code division multiple access (Code Division Multiple Access is called for short " CDMA ") is the mobile communication technology that grows up on spread spectrum technic, and it utilizes orthogonal code to distinguish different user, and data are carried out passing through transmission of radio links behind the spread spectrum.CDMA technology has the confidentiality height, strong interference immunity, availability of frequency spectrum height, the network planning is simple, power system capacity is big and have characteristics such as elasticity, and become the mainstream technology of mobile communication future development, present several 3G (Third Generation) Moblie (The Third Generation, be called for short " 3G ") technical standard, comprise CDMA 2000 (Code Division Multiple Access2000, be called for short " CDMA2000 "), Wideband Code Division Multiple Access (WCDMA) (Wideband Code Division MultipleAccess, be called for short " WCDMA ") and TD SDMA (Time Division SynchronousCode Division Multiple Access, abbreviation " TD-SCDMA ") all based on the CDMA access way.
Because each user's that CDMA adopts spreading code can not guarantee complete quadrature at receiving terminal, therefore the signal of user's transmission can produce interference noise to other users, be that cdma system is a self-interference system, the covering of system, capacity and communication quality are interrelated, each other influence.Especially in low traffic density area, transmitting power with respect to travelling carriage, the transmitting power of base station is enough big, because the transmitting power of travelling carriage is limited, network coverage is subject to up link, and the cell boarder of up link is subjected to the influence of ascending load, and cell size depends on ascending load institute loaded service amount, and the traffic carrying capacity that the sub-district is born is by the decision of sub-district area, cyclic constraint each other.If can find comparatively desirable balance point, can not only satisfy business demand, and can reduce network cost.For example, in the WCDMA system, transmission power of mobile station is to define in standard, because the mobile phone transmitting power is limited, up link then becomes the limitation link that the WCDMA system covers.
In cdma system, the loading condition of up link waits by the ascending load factor, noise rise and to weigh.The ascending load factor (is used η
ULExpression), noise rise (representing with noise rise), back noise (are used P
NThe expression) and uplink interference (use I
TotalExpression) satisfy the relation of following formula (1):
Wherein, in cdma system, back noise P
NBy the parameter setting, be used for representing the noise that current area is intrinsic; Uplink interference I
TotalMeasure I in the WCDMA system by physical layer
TotalBe total received power in broadband (Received Total Wideband Power is called for short " RTWP "), I in the CDMA2000 system
TotalBe received field strength indication (Receiving Signal StrengthIndicator is called for short " RSSI "), the actual back noise that has wherein comprised the sub-district (is used P
N, actualExpression) and the noise of user generation in the sub-district.
The actual back noise P of sub-district
N, actualComprise the interference of thermal noise and other sub-districts.Wherein, thermal noise changes with variation of temperature, is a change procedure relatively slowly; The interference of other sub-districts changes with the telephone traffic of other sub-districts, because the variation of telephone traffic every day of any one sub-district all is very large, the variation of other area interference is than very fast, and amplitude of variation is bigger, and this has caused up actual back noise P in a day
N, actualAlter a great deal.
For the ascending load of more accurate measurement system, make the load control algolithm can compare control accurately, require the back noise P that sets
NIt is more accurate to be provided with, and promptly tries one's best near the actual back noise P of current area
N, actual, otherwise can cause depending on the η of measurement
UL, bigger deviation appears in noise rise etc., uses the ascending load control algolithm of these parameters to bring bigger error thereby give.For example, when the neither one user existed in the current area, then corresponding load factor should be 0, if the back noise P that is provided with
NBe-105 decibels of millis (dBm), actual back noise P
N, actualFor-102dBm, the back noise P that be provided with this moment
NActual back noise P with the sub-district
N, actualDiffer 3dB, promptly differed 2 times.At this moment, according to formula (1), will calculate current load factor η
ULBe 0.5, noise rise is 3dB, depends on the η of measurement
UL, bigger deviation appears in noiserise etc., give and use the ascending load control algolithm of these parameters to bring bigger error.
The back noise update method is based on manually operated in the cdma system of prior art scheme one.When requiring operating personnel to select not have in the sub-district user or user seldom, this scheme carries out uplink interference I
TotalMeasurement, and with certain mean value of measured value back noise P as Set For Current
N
Prior art scheme one needs artificial control, and Operation and Maintenance is very inconvenient, and therefore for convenience of Operation and Maintenance, back noise upgrades and also can carry out automatically in the existing C DMA system.
The back noise update method can be carried out automatically in the cdma system of prior art scheme two.This scheme requires system to monitor the equivalent user number of each sub-district in real time, as when finding that the equivalent user number of certain sub-district and adjacent cell thereof is all relatively lower, then this sub-district is started back noise and upgrade, with the uplink interference I of a period of time
TotalBack noise P after conduct is upgraded after the measured value filtering
N
Measure uplink interference I when as can be seen, prior art scheme one and prior art scheme two all need the selective system load light
TotalTo obtain back noise P
N, main like this is to consider in this case, current back noise P
NBe approximately equal to current uplink interference I
Total
In actual applications, there is following problem in such scheme: the back noise P that existing technical scheme is provided with
NInaccurate, can not reflect the back noise of current area really.
Cause the main cause of this situation to be, existing technical scheme is measured when all the selective system load is light, the situation when the taking into account system load is not higher, so other sub-districts do not count the back noise P of current area to the interference of current area
N, and when system load was higher, other sub-districts can not be ignored the interference of current area, thereby caused the back noise P that is provided with
NInaccurate; In addition, existing technical scheme is not considered variation of temperature, i.e. the back noise P that is caused by variations in temperature
NVariation do not consider yet, therefore use the back noise of existing technical scheme setting can not truly reflect the back noise of current area.
Summary of the invention
In view of this, main purpose of the present invention is to provide the method for upgrading back noise in a kind of code division multiple access system automatically, it is more accurate to make that system is provided with back noise, and system can upgrade back noise adaptively according to the variation of temperature and other area interference, particularly also can the adaptive updates back noise when system's high capacity, stronger anti-bursty interference ability is provided simultaneously.
For achieving the above object, the invention provides the method for upgrading back noise in a kind of code division multiple access system automatically, comprise following steps:
The described code division multiple access system of A carries out initialization to described back noise;
B receives the measurement report of uplink interference and calculates the current time back noise;
C carries out the current time back noise input low pass filter that described step B calculates smoothly;
When D need upgrade described back noise, upgrade described back noise with the output of described low pass filter; Described step B, C, the D execution that circulates.
Wherein, among the described step B, according to the chip snr computation current time back noise of described uplink interference, adjacent area interference factor and user's demodulation needs.
In addition, the method for obtaining the chip signal to noise ratio that described user's demodulation needs comprises: by parameter setting, or calculate by this user's upward signal interference ratio.
In addition, described low pass filter is a αLv Boqi.
In addition, described low pass filter is the linear smoothing filter.
In addition, described step B adopts counter that the measurement report of described uplink interference is counted, and described step D reaches back noise update cycle described counter of zero clearing and upgrade described back noise with the output of described low pass filter during count value in count value.
In addition, among the described step D, trigger the renewal of described back noise in the particular moment of setting in advance.
By finding that relatively the main distinction of technical scheme of the present invention and prior art is, the uplink interference I when the automatic method for updating of back noise is not merely hanged down according to system load in the cdma system of the present invention
TotalObtain system's back noise, but by uplink interference I
TotalCalculate back noise in conjunction with other relevant parameters, and result of calculation is carried out filtering level and smooth back output.
Difference on this technical scheme, brought comparatively significantly beneficial effect, promptly at first, owing to need when system load is low, not carry out when the present invention program realizes, the back noise of computing system at any time, therefore effectively avoided prior art when system load is low weight, could upgrade back noise, the defective of making an uproar and make an uproar and match at the bottom of the system can not be with high capacity the time in the end after the renewal; Secondly,, therefore also avoided the influence of bursty interference, made the back noise of setting more accurate because the present invention program also carries out the filtering smoothing processing to back noise; The 3rd, because the present invention program can self adaptation upgrade back noise automatically, therefore the back noise that is provided with can guarantee that the back noise of whenever setting can both reflect system's true back noise at that time more really along with the variation adaptive tracing of the true back noise of system; At last, adopt the present invention program, because system's back noise can be set more accurately, so CALCULATION OF PARAMETERS is more accurate, guarantees the accuracy of ascending load control algolithm, will improve the performance of whole system greatly.
Description of drawings
Fig. 1 is according to the flow chart that upgrades the method for back noise in the cdma system of a preferred embodiment of the present invention automatically.
Embodiment
For making the purpose, technical solutions and advantages of the present invention clearer, the present invention is described in further detail below in conjunction with accompanying drawing.
Basic principle of the present invention at first is described.The present invention reports back noise constantly according to uplink interference and other parameter value calculation uplink interference measurements of obtaining easily, then result of calculation is carried out filtering with the opposing bursty interference, and upgrades back noise in particular moment with filtering output value.Like this, carrying out back noise with regard to not needing to limit when can only system load low upgrades, the back noise value of upgrading has counted the interference of other sub-districts, and because system can the adaptive updates back noise, therefore the back noise of real-time update has also reflected the variation of temperature and load and the back noise that causes changes, and, therefore also can provide stronger anti-bursty interference ability owing to adopted filtering to report back noise constantly with level and smooth each measurement.
For clearer explanation the present invention program, the present invention program is elaborated below in conjunction with accompanying drawing.
According to the flow process of the method for automatically upgrading back noise in the cdma system of a preferred embodiment of the present invention as shown in Figure 1.
At first enter step 110, the system initialization back noise.Wherein, initialized back noise value P '
NCan measure by existing technical scheme, also can be an estimated value.
Then enter step 120, uplink interference I receives in system
TotalMeasurement report after, the back noise refresh counter is added one.Wherein, uplink interference I
TotalMeasurement report provide by physical layer.In a preferred embodiment of the present invention, the back noise refresh counter is used for uplink interference I
TotalMeasurement report count.
Then enter step 130, according to uplink interference I
TotalCalculate back noise and with the result of calculation input filter.Wherein, filter is a low pass filter, and multiple realization can be arranged, and is used for the smooth bottom noise, and the opposing bursty interference is effectively avoided bursty interference to be made an uproar in the end and upgraded the influence of precision.In a preferred embodiment of the present invention, employing has the αLv Boqi of good low-pass characteristic, and its transfer function is y (n)=α x (n)+(1-α) y (n-1), wherein, y (n) is the sampled point n output of filter constantly, and x (n) is the sampled point n input of filter constantly.In another preferred embodiment of the present invention, adopt the linear smoothing filter to replace αLv Boqi, can realize same purpose.Need to prove, in a preferred embodiment of the present invention, according to uplink interference I
TotalCalculating the method for back noise carries out according to following formula (2).
Formula (2) can obtain according to existing literature.Below obtaining of formula (2) elaborated.
Those of ordinary skill in the art know, ascending load factor η
ULAnother expression is also arranged, see following formula (3).
Wherein,
Be up average adjacent area interference factor, R
iBe the service rate of user i, (E
b/ N
o)
jBe the bit signal to noise ratio that user j demodulation needs, (E
c/ N
o)
jBe the chip signal to noise ratio that user j demodulation needs, W is the spreading rate of cdma system.Detailed description about formula (3) can be referring to " WCDMA technology and system " [1]; (E
c/ N
o)
jCan be by this user's upward signal interference ratio (Signal toInterference Ratio, be called for short " SIR ") calculate, concrete computational methods can be referring to " UMTS wireless network planning and optimization " [2], also can acquisition be set, or be that [3] provide in 200410081076.8 method is calculated and obtained according to application number by parameter.
Be familiar with those of ordinary skill in the art and promptly can obtain formula (2) by described formula of preamble (1) and formula (3) easily.
Then enter step 140, judge whether Counter Value equals back noise update cycle count value,, otherwise return step 120 if then enter step 150.Wherein, back noise update cycle count value can if need back noise to upgrade than very fast, then can be provided with less count value, otherwise then bigger count value is set as required in advance by default.
In step 150,, and, enter step 120 afterwards to upgrade current back noise when pre-filter output with counter zero setting.Wherein, will enter the next back noise update cycle after the counter zero setting.Those of ordinary skill in the art are appreciated that, this moment, the output of filter was to the level and smooth result of several sampled points before, therefore the bursty interference that may occur for certain sampled point can effectively be eliminated, thereby the output that makes filter is more near the true back noise of current area.
Carry out by the above-mentioned steps circulation, can realize that the self adaptation of system's back noise is upgraded automatically.
Need to prove, in the preferred embodiment of the invention described above, adopt the mode update system back noise in cycle, be familiar with persons of ordinary skill in the art may appreciate that and adopt other modes when to determine the update system back noise according to the count value of counter.For example, can trigger service time, start the update system back noise, decision also can manually be set when upgrade in some specific time.Do not influence essence of the present invention like this.
Though by reference some preferred embodiment of the present invention, the present invention is illustrated and describes, but those of ordinary skill in the art should be understood that, can do various changes to it in the form and details, and the spirit and scope of the present invention that do not depart from claims and limited.
Claims (7)
1. upgrade the method for back noise in the code division multiple access system automatically, it is characterized in that, comprise following steps:
The described code division multiple access system of A carries out initialization to described back noise;
B receives the measurement report of uplink interference and calculates the current time back noise;
C carries out the current time back noise input low pass filter that described step B calculates smoothly;
When D need upgrade described back noise, upgrade described back noise with the output of described low pass filter; And,
Described step B, C, the D execution that circulates.
2. upgrade the method for back noise in the code division multiple access system according to claim 1 automatically, it is characterized in that, among the described step B, according to the chip snr computation current time back noise of described uplink interference, adjacent area interference factor and user's demodulation needs.
3. upgrade the method for back noise in the code division multiple access system according to claim 2 automatically, it is characterized in that, the method of obtaining the chip signal to noise ratio that described user's demodulation needs comprises: by parameter setting, or calculate by this user's upward signal interference ratio.
4. upgrade the method for back noise in the code division multiple access system according to claim 1 automatically, it is characterized in that described low pass filter is a αLv Boqi.
5. upgrade the method for back noise in the code division multiple access system according to claim 1 automatically, it is characterized in that described low pass filter is the linear smoothing filter.
6. upgrade the method for back noise in the code division multiple access system according to claim 1 automatically, it is characterized in that, described step B adopts counter that the measurement report of described uplink interference is counted, and described step D reaches back noise update cycle described counter of zero clearing and upgrade described back noise with the output of described low pass filter during count value in count value.
7. upgrade the method for back noise in the code division multiple access system according to claim 1 automatically, it is characterized in that, among the described step D, trigger the renewal of described back noise in the particular moment of setting in advance.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2005100246375A CN100386974C (en) | 2005-03-25 | 2005-03-25 | Method of automatic background noise update in CDMA system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2005100246375A CN100386974C (en) | 2005-03-25 | 2005-03-25 | Method of automatic background noise update in CDMA system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1671070A CN1671070A (en) | 2005-09-21 |
| CN100386974C true CN100386974C (en) | 2008-05-07 |
Family
ID=35042158
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB2005100246375A Active CN100386974C (en) | 2005-03-25 | 2005-03-25 | Method of automatic background noise update in CDMA system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN100386974C (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102195720B (en) * | 2010-03-15 | 2014-03-12 | 中兴通讯股份有限公司 | Method and system for measuring bottom noise of machine |
| WO2014113950A1 (en) * | 2013-01-24 | 2014-07-31 | 华为技术有限公司 | Method and device for controlling uplink load |
| CN114499710B (en) * | 2022-04-02 | 2022-06-21 | 成都爱瑞无线科技有限公司 | Background noise change measuring method, background noise change measuring device, background noise change measuring system, electronic device, and storage medium |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1280453A (en) * | 1999-07-12 | 2001-01-17 | Sk电信股份有限公司 | Device and method for measuring reverse link circuit quality in code division multiple access system |
| CN1380762A (en) * | 2001-04-07 | 2002-11-20 | 华为技术有限公司 | Calling permission control method in multiservice code division multiple address mobile communication system |
| US6708023B1 (en) * | 2000-02-25 | 2004-03-16 | Motorola Inc. | Method and apparatus for noise suppression of received audio signal in a cellular telephone |
-
2005
- 2005-03-25 CN CNB2005100246375A patent/CN100386974C/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1280453A (en) * | 1999-07-12 | 2001-01-17 | Sk电信股份有限公司 | Device and method for measuring reverse link circuit quality in code division multiple access system |
| US6708023B1 (en) * | 2000-02-25 | 2004-03-16 | Motorola Inc. | Method and apparatus for noise suppression of received audio signal in a cellular telephone |
| CN1380762A (en) * | 2001-04-07 | 2002-11-20 | 华为技术有限公司 | Calling permission control method in multiservice code division multiple address mobile communication system |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1671070A (en) | 2005-09-21 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US6760567B1 (en) | Apparatus and method for measuring quality of a reverse link in a CDMA system | |
| CN1327723C (en) | Downlink power control for multiple downlink time slots in tdd communication systems | |
| CN102484542B (en) | Load estimation in wireless communication | |
| US8184532B2 (en) | Estimation of interference variation caused by the addition or deletion of a connection | |
| CN106937306B (en) | A kind of network quality appraisal procedure and device | |
| EP1419588B1 (en) | System for adjusting gain of a mobile station during an idle period of the serving base station | |
| CN102905278A (en) | Management method, management device and management system for coverage optimization | |
| CN107807346A (en) | Adaptive WKNN outdoor positionings method based on OTT Yu MR data | |
| CN106792752A (en) | base station signal coverage self-optimization method and system | |
| CN101588590B (en) | Method and device for estimating channel quality of uplink data channels | |
| CN103327505B (en) | The defining method of Physical Cell Identifier and device | |
| CN100438373C (en) | Low power interference signal code power (ISCP) measurement | |
| CN100386974C (en) | Method of automatic background noise update in CDMA system | |
| CN109981196A (en) | A kind of network structure appraisal procedure and device | |
| CN102448103B (en) | Method and device for intelligently improving wireless radio frequency index in distributed network in real time | |
| CN1310530A (en) | Method for regulating to reach signal quality target and relevant transceiver | |
| CN100546212C (en) | Method, device and the mobile communication system of variable power in the prediction air interface | |
| US10911083B2 (en) | Method of adjusting and controlling the receiver power adaptation according to the transmission environment in eNodeB LTE system | |
| AU2004206672B2 (en) | Method and apparatus for network management using perceived signal to noise and interference indicator | |
| CN103313371B (en) | The power processing method and device of PUCCH format1 series | |
| JP4803182B2 (en) | Received signal quality measurement | |
| CN109041102B (en) | Cellular frequency evaluation system and frequency evaluation method | |
| CN100512269C (en) | A method for on-site test of demodulation performance of WCDMA mobile communication system | |
| CN100411475C (en) | Up-load estimating method in mobile communication system | |
| CN107222919A (en) | A kind of method and apparatus of SNR estimations |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |