CN102281569B - Femto base station is based on the measurement control method of distributed strategy - Google Patents
Femto base station is based on the measurement control method of distributed strategy Download PDFInfo
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Abstract
The invention discloses a kind of Femto base station measurement control method based on distributed strategy, HNB be periodically detected this community state and with adjacent area HNB interaction mode information, according to adjacent area status information real-time update neighboring BS information list, in the measurement list object being handed down to UE, only in configuration HNB neighboring BS information list, load is light, disturbing little or do not produce congested community, the severe or poor community of information is then not as the measurement object of UE. Thus avoid available resources not, disturb community that is excessive or that be in congestion state to also serve as measurement object, decrease the UE community number measured, reduce the measurement burden of UE, decrease the time overhead of measurement process, thus the number of attempt decreased in handoff procedure, and then decrease the call drop probability produced in handover delay and handoff procedure, improve handover success rate.
Description
Technical field
The present invention relates to wireless mobile telecommunication technology field, particularly to a kind of Femto base station measurement control method based on distributed strategy.
Background technology
Currently, communication technology develops rapidly, and 3-G (Generation Three mobile communication system) (3G) is commercial in global scale. In communication network, under ensureing the premise of network capacity and quality, improving the network coverage, be an important problem, therefore various form base stations occur in succession, such as macro base station, microcell base station, distributed base station etc. In order to strengthen the weak link of in-door covering, occur in that (femtocell, is also called Home eNodeB or HomeNodeB in a kind of Femto base station at present, the follow-up convenience for describing, it is referred to as HNB), the feature of this base station is that volume is little, power is little, plug and play.
HNB can be deployed in the private site such as family, medium-sized and small enterprises as the dedicated resources of private user. Radio communication service, broadband inserting service, fixed communication service can be obtained, it is also possible to utilize HNB to build the system covering some common chamber inner region by HNB. Functionally seeing, HNB is consistent with ordinary base station (i.e. macro base station), but cost, realize complexity and many technical specification parameters etc. because of applied environment simple, the requirement of HNB is lower than ordinary base station.
Being illustrated in figure 1 typical HNB system architecture schematic diagram, HNB system is made up of HNB gateway (HNBGW), HNB and user terminal (Userequipment, UE). HNBGW may be considered the agency of radio network controller (RadioNetworkController, RNC), and HNB normally comprises the function of NodeB and RNC. HNB is based upon on following basis based on the switching of distributed strategy: can pass through HX2 interface, core net or other mode interactive information between adjacent node HNB, each HNB maintains a neighboring BS information list, by the information interactive refreshing neighboring BS information list with adjacent HNB timing or variable interval.
HNB can be divided into three below step based on the handoff procedure of distributed strategy: 1) handover measurement; 2) switch decision; 3) switching performs. As in figure 2 it is shown, handover measurement is completed by UE and HNB, switch decision carries out in HNB, and switching performs to complete under UE, HNB and HNBGW cooperate jointly. The handover measurement procedure carried out between UE and HNB includes " measure control " and " measurement report " signaling is mutual, as shown in Figure 3, " measuring and control " is the HNB measurement requirement being handed down to UE, and " measurement report " is, after UE measures according to measurement requirement, to report the measurement result of HNB. Under normal circumstances, HNB when UE business is set up, or can find in the periodic measurement report reported in UE communication process when UE received signal strength in this HNB Serving cell drops to a certain degree, sends event mode to UE and measures control message.
HNB is handed down to event mode " measurement controls " message of UE and comprises a measurement list object, and list lists HNB and requires the UE community measured, and all communities in list are measured UE and report measurement results is to HNB. It is true that the probability that the community that partial information is severe (community such as link-quality difference) becomes switching target small area is only small, even if becoming switching target small area, handoff procedure also easily occurs call drop. Therefore, the measurement of this cell portion is nonsensical and loses time by UE.
Summary of the invention
The present invention proposes a kind of Femto base station method measuring control based on distributed strategy, to reduce the pendulous frequency of UE, shortens the measurement time, reduces and measure expense, increases handover success rate.
Femto base station of the present invention is based on the measurement control method of distributed strategy, including step:
HNB initializes after starting, and generates and safeguard a neighboring BS information list;
After HNB triggers event mode measurement control process, UE will be built according to neighboring BS relationship and measure list object, and this UE measurement list object will be handed down to UE as measuring the measurement object controlled in message,
On above step basis,
The described neighboring BS information list that HNB generates includes status information;
After HNB generates and safeguards described neighboring BS information list, HNB triggers event mode and measured Cheng Qian, further comprise the steps of: HNB detect cell status, and with adjacent area HNB interaction mode information, the status information of corresponding adjacent area in neighboring BS information list according to mutual described state information updating;
After HNB builds described UE measurement list object according to neighboring BS relationship, first according to the status information in described neighboring BS information list, described UE is measured list object to be optimized, UE after optimization measuring list object again and is handed down to UE as the measurement object in measurement control message, the Optimality Criteria of described optimization is: deletion list object is measured from UE in the community that state does not meet switching requirement.
Preferably, the detection that described step HNB detects in cell status is to be periodically detected, the status information that HNB and adjacent area HNB is up-to-date alternately, the status information of corresponding adjacent area in neighboring BS information list according to mutual up-to-date state information updating.
Preferably, described status information includes load condition, and described load condition is specially uplink downlink code resources occupation rate, and described switching requires as uplink downlink code resources occupation rate lower than predetermined load threshold.
Preferably, described status information includes uplink interference state, the detection method of described uplink interference state is: HNB measures and calculate the ISCP (InterferenceSignalCodePower of each ascending time slot, Interference Signal Code Power) assembly average, when the number that ISCP assembly average exceedes the time slot of threshold value exceedes predetermined value, judging that uplink interference state is as exception, be otherwise normal, described switching requires that the uplink interference state for community is normal.
Preferably, described status information includes uplink congestion state, the detection method of described uplink congestion state is: HNB measures and calculate the RTWP (ReceivedTotalWidebandPower of each ascending time slot, received bandwidth total power) assembly average, corresponding threshold value is set uplink congestion is divided into three kinds of states: normally, transship and underload, calculate the timeslot number shared by three kinds of states, using uplink congestion state final as community for states maximum for shared timeslot number, it is normal that described switching requires as uplink congestion state.
Preferably, described status information includes downlink congestion state, the detection method of described downlink congestion state is: HNB measures and calculate the TCP (TransmittedCarrierPower of each descending time slot, launch carrier power) assembly average, corresponding threshold value is set downlink congestion is divided into three kinds of states: normally, transship and underload, calculate the timeslot number shared by three kinds of states, using downlink congestion state final as community for states maximum for shared timeslot number, it is normal that described switching requires as downlink congestion state.
Preferably, described status information includes the combination in any of load condition, uplink interference state, uplink congestion state and downlink congestion state, total described switching requires each to meet the corresponding combination that corresponding switching requires for described load condition, uplink interference state, uplink congestion state and downlink congestion state
Described load condition is specially uplink downlink code resources occupation rate, and when described uplink downlink code resources occupation rate is lower than predetermined load threshold, described load condition meets described switching requirement;
The detection method of described uplink interference state is: HNB measures and calculate the ISCP assembly average of each ascending time slot, when the number that ISCP assembly average exceedes the time slot of threshold value exceedes predetermined value, judge that uplink interference state is as abnormal, being otherwise normal, described uplink interference state meets described switching requirement time normal;
The detection method of described uplink congestion state is: HNB measures and calculate the RTWP assembly average of each ascending time slot, corresponding threshold value is set uplink congestion is divided into three kinds of states: normally, transship and underload, calculate the timeslot number shared by three kinds of states, using uplink congestion state final as community for states maximum for shared timeslot number, described uplink congestion state meets described switching requirement time normal;
The detection method of described downlink congestion state is: HNB measures and calculate the TCP assembly average of each descending time slot, corresponding threshold value is set downlink congestion is divided into three kinds of states: normally, transship and underload, calculate the timeslot number shared by three kinds of states, using downlink congestion state final as community for states maximum for shared timeslot number, described downlink congestion state meets described switching requirement time normal.
Femto base station of the present invention is based on the measurement control method of distributed strategy, before the UE community measurement to measuring in list object, HNB elder generation and adjacent area HNB interaction mode information, UE is measured list object and carries out priori optimization by the state according to adjacent cell, state is not met adjacent cell deletion from UE measurement list object that switching requires, thus alleviating the measurement workload of UE, shorten the measurement time, reduce measurement expense, decrease the number of attempt in handoff procedure, and then reduce the call drop probability produced in handover delay and handoff procedure, improve handover success rate.
Accompanying drawing explanation
Fig. 1 is typical HNB system architecture schematic diagram;
Fig. 2 is the HNB handoff relation figure based on distributed strategy;
Fig. 3 is that Femto base station is based on the schematic flow sheet of handover measurement in the handoff procedure of distributed strategy;
Fig. 4 is the Femto base station of the present invention schematic flow sheet based on the measurement control method of distributed strategy.
Detailed description of the invention
In traditional handover measurement procedure, choosing is not deleted in the community measured in list object by UE, directly to measuring all of community measurement in list object. Thus, the community (such as load weight, disturbing community that is big or that be in congestion state) that information is severe, it also to be measured by UE. It is therefore necessary to the measurement list object that HNB is handed down to UE carries out priori optimization, reduce the number of attempt in handoff procedure, and then reduce handover delay and reduce the call drop probability produced in handoff procedure, improve handover success rate. The present invention is explained in detail below in conjunction with accompanying drawing.
The present invention is to provide a kind of Femto base station improved method measuring control based on distributed strategy, as shown in Figure 4, specifically include step:
Step 101, HNB initialize after starting, and generate and safeguard a neighboring BS information list, and described neighboring BS information list is including, but not limited to the frequency of adjacent area, scrambler. Being optimized in order to following UE is measured list object, described neighboring BS information list adds adjacent area status information. Adjacent area status information in the neighboring BS information list initially generated zero setting can also be set to default value, when following step 102 updates after detecting again.
Step 102, HNB detect cell status, and with adjacent area HNB interaction mode information, the status information option of corresponding adjacent area in neighboring BS information list according to mutual described state information updating. State-detection herein can be periodically detected, and the described cycle can arbitrarily set, and HNB constantly updates the status information in Neighboring Cell List. When HNB is every time to adjacent area HNB transmission information, if there being much information to need to send, then this much information is encapsulated in same frame and transmits, if only a kind of information needs transmission, then individually send this information.
After step 103, HNB trigger event mode measurement control process, list object is measured by building original UE according to neighboring BS relationship, after described original UE measurement list object being optimized according to up-to-date neighboring BS information list, then the UE measurement list object after optimizing is handed down to UE as measuring the measurement object controlled in message. The Optimality Criteria of described optimization is: state does not meet community deletion from UE measurement list object that switching requires, generates new UE and measure list object. What above-mentioned neighboring BS relationship characterized is all adjacent cells adjacent with HNB affiliated subdistrict.
In step 102, HNB detects the status information of this Serving cell, status information herein can be load condition, uplink interference state, uplink congestion state, downlink congestion state or four combination in any, these four state can be related to whether adjacent cell can become the switching target small area of this HNB. During practical operation, it is possible to optionally detect these four state according to demand.
The HNB detection method to load condition: calculate the code resources occupation rate of uplink downlink, occupancy is more high shows that load is more heavy, the load being adapted as switching target small area is not to be exceeded predetermined load threshold, and this predetermined load threshold is threshold value set in advance, can be configured as required. When status information is only characterized by load condition, switching requires as uplink downlink code resources occupation rate lower than predetermined load threshold.
The detection method of uplink interference state is by HNB: HNB measures and calculate each ascending time slot ISCP assembly average, and add up ISCP value and exceed the timeslot number count of threshold value (i.e. abnormality), when abnormality timeslot number count exceedes threshold value, then judge that ISCP is as abnormal (representing with " 1 "), be otherwise normal condition (representing with " 0 "). When status information is only characterized by uplink interference state, the community that satisfied switching requires is uplink interference state is normal community.
The detection method of uplink congestion state is by HNB: HNB measures and calculate the RTWP assembly average of each ascending time slot, corresponding threshold value is set uplink congestion is divided into three kinds of states: normal (00), overload (01) and underload (11), calculate the timeslot number shared by three kinds of states, with corresponding count threshold, total uplink congestion state of this community is made decisions again, by 00,01,11 normal, overload, the underload three kinds of uplink congestion states identifying this community respectively. When status information is only characterized by uplink congestion state, the community that satisfied switching requires is uplink congestion state is normal community.
The detection method of downlink congestion state is by HNB: HNB measures and calculate the TCP assembly average of each descending time slot, corresponding threshold value is set downlink congestion is divided into three kinds of states: normal (00), overload (01) and underload (11), calculate the timeslot number shared by three kinds of states, with corresponding count threshold, total downlink congestion state of this community is made decisions again, by 00,01,11 normal, overload, the underload three kinds of downlink congestion states identifying this community respectively. When status information is only characterized by downlink congestion state, the community that satisfied switching requires is downlink congestion state is normal community.
As it has been described above, when status information is a kind of in four kinds of states, corresponding switching requirement is that this kind of state individually meets switching requirement; Status information can also be that in four kinds of states, both combinations any, any three combination or whole four are combined, then switching accordingly requires it is that various state each meets the corresponding combination switching requirement.
As a preferred embodiment, status information includes aforementioned whole four kinds of states, therefore, total switching requires to be that four kinds of states are satisfied by switching requirement, be namely uplink downlink code resources occupation rate specifically lower than predetermined load threshold, uplink interference state for normal, uplink congestion state for normal and downlink congestion state is normal. The neighboring BS information list of self real-time servicing is traveled through by HNB, if finding in the every status information in the adjacent area of neighboring BS information list maintenance, as long as there being one to be unsatisfactory for switching requirement, Ze Jianggai community is measured list object from original UE and rejected.
Invention described above embodiment, is not intended that limiting the scope of the present invention. Any amendment, equivalent replacement and improvement etc. made within the spirit and principles in the present invention, should be included within the claims of the present invention.
Claims (6)
1. Femto base station is based on a measurement control method for distributed strategy, including step:
HNB initializes after starting, and generates and safeguard a neighboring BS information list;
After HNB triggers event mode measurement control process, UE will be built according to neighboring BS relationship and measure list object, and this UE measurement list object will be handed down to UE as measuring the measurement object controlled in message,
It is characterized in that,
The described neighboring BS information list that HNB generates includes status information, and described status information includes the combination in any of load condition, uplink interference state, uplink congestion state and downlink congestion state;
After HNB generates and safeguards described neighboring BS information list, HNB triggers event mode and measured Cheng Qian, further comprise the steps of: HNB and be periodically detected cell status, and with adjacent area HNB up-to-date alternately status information, the status information of corresponding adjacent area in neighboring BS information list according to mutual described up-to-date state information updating;
After HNB builds described UE measurement list object according to neighboring BS relationship, first according to the status information in described neighboring BS information list, described UE is measured list object to be optimized, UE after optimization measuring list object again and is handed down to UE as the measurement object in measurement control message, the Optimality Criteria of described optimization is: deletion list object is measured from UE in the community that state does not meet switching requirement.
2. Femto base station according to claim 1 is based on the measurement control method of distributed strategy, it is characterized in that, described status information includes load condition, described load condition is specially uplink downlink code resources occupation rate, and described switching requires as uplink downlink code resources occupation rate lower than predetermined load threshold.
3. Femto base station according to claim 1 is based on the measurement control method of distributed strategy, it is characterized in that, described status information includes uplink interference state, the detection method of described uplink interference state is: HNB measures and calculate the ISCP assembly average of each ascending time slot, when the number that ISCP assembly average exceedes the time slot of threshold value exceedes predetermined value, judging that uplink interference state is as exception, be otherwise normal, described switching requires that the uplink interference state for community is normal.
4. Femto base station according to claim 1 is based on the measurement control method of distributed strategy, it is characterized in that, described status information includes uplink congestion state, the detection method of described uplink congestion state is: HNB measures and calculate the RTWP assembly average of each ascending time slot, corresponding threshold value is set uplink congestion is divided into three kinds of states: normally, transship and underload, calculate the timeslot number shared by three kinds of states, using uplink congestion state final as community for states maximum for shared timeslot number, it is normal that described switching requires as uplink congestion state.
5. Femto base station according to claim 1 is based on the measurement control method of distributed strategy, it is characterized in that, described status information includes downlink congestion state, the detection method of described downlink congestion state is: HNB measures and calculate the TCP assembly average of each descending time slot, corresponding threshold value is set downlink congestion is divided into three kinds of states: normally, transship and underload, calculate the timeslot number shared by three kinds of states, using downlink congestion state final as community for states maximum for shared timeslot number, it is normal that described switching requires as downlink congestion state.
6. Femto base station according to claim 1 is based on the measurement control method of distributed strategy, it is characterized in that, described switching requires each to meet the corresponding combination that corresponding switching requires for described load condition, uplink interference state, uplink congestion state and downlink congestion state
Described load condition is specially uplink downlink code resources occupation rate, and when described uplink downlink code resources occupation rate is lower than predetermined load threshold, described load condition meets described switching requirement;
The detection method of described uplink interference state is: HNB measures and calculate the ISCP assembly average of each ascending time slot, when the number that ISCP assembly average exceedes the time slot of threshold value exceedes predetermined value, judge that uplink interference state is as abnormal, being otherwise normal, described uplink interference state meets described switching requirement time normal;
The detection method of described uplink congestion state is: HNB measures and calculate the RTWP assembly average of each ascending time slot, corresponding threshold value is set uplink congestion is divided into three kinds of states: normally, transship and underload, calculate the timeslot number shared by three kinds of states, using uplink congestion state final as community for states maximum for shared timeslot number, described uplink congestion state meets described switching requirement time normal;
The detection method of described downlink congestion state is: HNB measures and calculate the TCP assembly average of each descending time slot, corresponding threshold value is set downlink congestion is divided into three kinds of states: normally, transship and underload, calculate the timeslot number shared by three kinds of states, using downlink congestion state final as community for states maximum for shared timeslot number, described downlink congestion state meets described switching requirement time normal.
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| CN102917404A (en) * | 2012-09-04 | 2013-02-06 | 大唐移动通信设备有限公司 | Method and device for pre-processing cell switch |
| CN103957550B (en) * | 2014-04-22 | 2017-04-19 | 电子科技大学 | Method and system for detecting base station failures in LTE trunking system |
| CN104053195B (en) * | 2014-06-30 | 2018-03-27 | 京信通信系统（中国）有限公司 | A kind of method and device for determining blacklist list member |
| CN107567040A (en) * | 2016-07-01 | 2018-01-09 | 中兴通讯股份有限公司 | A kind of network optimized approach, core net and base station |
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| CN102098728A (en) * | 2011-01-05 | 2011-06-15 | 北京邮电大学 | Mobile load balancing method |
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| GB2406473B (en) * | 2003-09-27 | 2006-02-15 | Motorola Inc | A method of determining the identity of an unknown neighbour cell,and apparatus therefor |
| CN102118770B (en) * | 2010-01-05 | 2014-05-21 | 鼎桥通信技术有限公司 | Configuration methods for neighbor lists and same-frequency/different-frequency lists |
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| CN101278581A (en) * | 2005-10-04 | 2008-10-01 | 艾利森电话股份有限公司 | Automatic building of neighbor lists in mobile system |
| CN102098728A (en) * | 2011-01-05 | 2011-06-15 | 北京邮电大学 | Mobile load balancing method |
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