CN1913703A - Method and system for correcting RTT measuring valve by multi-sector cell - Google Patents

Method and system for correcting RTT measuring valve by multi-sector cell Download PDF

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Publication number
CN1913703A
CN1913703A CNA2006100618866A CN200610061886A CN1913703A CN 1913703 A CN1913703 A CN 1913703A CN A2006100618866 A CNA2006100618866 A CN A2006100618866A CN 200610061886 A CN200610061886 A CN 200610061886A CN 1913703 A CN1913703 A CN 1913703A
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sector
time delay
cell
channel time
rtt
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CN100455129C (en
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杨平
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Huawei Technologies Co Ltd
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Huawei Technologies Co Ltd
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Abstract

This invention relates to a wireless positioning technology, which particularly relates to a method for calibrating the RTT measured value in positioning technology for multi-sector area. In the case of multi-sector area, the specific sector where the UE locates in the multi-sector area is identified by the use of the information of adjacent areas. Then RTT value is calibrated based on the relay value of RF channel of the sector, after that, a method is selected according to the RTT value to position continuously.

Description

The method and system that multi-sector cell is proofreaied and correct the RTT measured value
Technical field
The present invention relates to a kind of wireless location technology, relate in particular to the method that the RTT measured value in a kind of multi-sector cell location technology is proofreaied and correct.
Background technology
The research of wireless location technology starts from the automatic vehicle location system of the sixties in 20th century, this technology extensive use in scopes such as public transport, taxi dispatching and public security tracking subsequently.Afterwards, along with the Requirement Increases of people to location-based information service, wireless location technology obtains more researchers' concern, and the appearance of global positioning system (GPS) makes that more wireless location technology has produced qualitative leap, and positioning accuracy is greatly enhanced.
Along with the development of mobile communication industry, professional innovation has become the basic motive force of network and technical development.Simultaneously, the operation mode of new business changes, and healthy value chain then is the basic assurance of new business development.
At present, voice service is still the main body of mobile communication business, and various novel mobile value-added service and mobile data services then are the powerful points of economic increase in mobile communication market.Moving communicating field is one of most hotly competitive in recent years industry, operator more and more needs the business of otherness to enhance competitiveness, a kind of mobile value-added service that LCS (Location Services, location service) is generally had an optimistic view of, and will obtain to develop rapidly.
In the WCDMA system, three kinds of location technology methods have been defined, i.e. Cell ID, OTDOA and A-GPS.Wherein OTDOA and A-GPS propose high requirement to network or mobile phone, and the former has increased network cost, and the latter has increased the terminal cost, and A-GPS also is subjected to UE environmental constraints of living in simultaneously.And the Cell ID localization method of directly getting the center of housing estate position is realized the simplest, but precision also is the poorest, therefore more existing agreements have proposed a kind of enhancement mode Cell ID localization method, be Cell ID+RTT (Cell Identity with RoundTrip Time, cell ID is in conjunction with two-way time), utilize the base station to propagate the contact time span, just can determine that mobile phone is to the distance between the base station to the signal between the mobile phone.
Referring to Fig. 1, UE for non-soft handover area, owing to can only test the RTT that connects the base station, Rx-Tx Time Difference (reception of terminal inner and transmission delay error) value in conjunction with UE obtains ToA (Time of Arrival, the time of advent) distance (ToA distance=[(RTT-Rx-Tx TimeDifference)/2] * C, C is the light velocity), therefore can positioning range can only be to be initial point with the base station transmit antennas, radius be 1 annulus (omni cell) or 1 circular arc ring (sector cell) of ToA distance.
Referring to Fig. 2, if UE is in soft handover area, then can test the RTT that obtains a plurality of base stations (Active Set), obtain a plurality of ToA distances in conjunction with the Rx-Tx Time Difference of UE, thereby be initial point with a plurality of base stations, obtain many annulus or circular arc ring.By the intersection point of these many annulus or circular arc ring, particular location that just can positioning UE.
In the OTDOA location, also the delay inequality TDOA that can use UE to measure is converted into the ToA distance in conjunction with the RTT value.
3GPP is defined as RTT:
RTT=T The RX antenna-T The TX antenna
Wherein, T The TX antennaFinger sends to the beginning delivery time of descending DPCH (Dedicated Physical Channel, the DPCH) frame of UE, and reference point is the transmitting antenna mouth, T The RX antennaRefer to corresponding up DPCCH/DPDCH (Dedicated Physical Control Channel from UE, Dedicated Physical Control Channel/Dedicated Physical Data Channel, Dedicated Physical Data Channel) the beginning time of reception of frame, reference point is the reception antenna mouth.
Because the RTT measurement is to carry out in the base band of NodeB,, select first footpath to calculate RTT value, i.e. RTT according to the multipath information that search is come out Measured value=T The RX base band-T The TX base bandTherefore, RTT=RTT Measured value-(T RXDuring passage Prolong+ T The TX channel time delay).
T wherein The RX passageThe time delay finger propagation delay time number from the reception antenna to the base band of collecting mail, T The TX passageThe time delay propagation delay time from the base band to the transmitting antenna that refers to transmit.
In actual applications, the situation that many times exists 1 sub-district to form by a plurality of sectors.The feeder line length of these a plurality of sectors etc. is not quite similar, and also can exist sometimes than big-difference, i.e. the T of each sector The RX passageTime delay and T The TX passageTime delay value there are differences.Because RTT only knows cell information in measuring, and does not know sector auxiliary information, thereby can't carry out accurate measurement or the correction of RTT, has reduced the positioning accuracy performance.
Summary of the invention
The object of the present invention is to provide method that a kind of multi-sector cell proofreaies and correct the RTT measured value and corresponding RTT measurement update system, this method and system can be proofreaied and correct the RTT measured value that is positioned at multi-sector cell UE, thereby improves the positioning accuracy of UE.
For achieving the above object, a kind of multi-sector cell of the present invention method that the RTT measured value is proofreaied and correct specifically comprises the steps:
A, determine the concrete sector at UE place;
B, initiation RTT measure, and obtain the RTT measured value;
The radio-frequency channel time delay value of C, extraction sector, UE place;
D, come the RTT measured value is proofreaied and correct according to the radio-frequency channel time delay value among the described step C.
Wherein, the radio-frequency channel time delay value of sector, UE place comprises T among the described step C The RX channel time delayAnd T The TX channel time delay
In step D, pass through RTT Measure-(T The RX channel time delay+ T The TX channel time delay) computing formula proofread and correct the RTT measured value.
Comprise also whether the sub-district of judging the UE place is the step of multi-sector cell before the described steps A.
Whether sub-district, the described UE of judgement place is that multi-sector cell specifically may further comprise the steps:
The metrical information of a, radio network controller inquiry UE if any metrical information, is then directly obtained the CELL ID of UE sub-district of living in; Otherwise UE is initiated paging, and UE transfers to state of activation, and the state transitions success message that radio network controller reports according to UE is determined the residing sub-district of UE Cell ID;
The Cell id information that b, basis are obtained determines whether sub-district, UE place is multi-sector cell.
Described steps A specifically comprises:
A1, extract the neighboring BS information of sub-district, UE place, and the neighboring BS information corresponding with each sector of preserving in advance in the radio network controller mates;
A2, determine the concrete sector at UE place according to matching result.
The present invention also provides a kind of multi-sector cell RTT measurement update system, is used for the RTT measured value is proofreaied and correct, and described system includes radio network controller, and described radio network controller comprises:
Memory cell in order to storage cell attribute information, comprises the neighboring BS information of multi-sector cell attribute information and each sector correspondence, and stores the radio-frequency channel time delay value of each sector correspondence;
Information extraction unit is in order to extract UE sub-district of living in neighboring BS information;
Identifying unit, the neighboring BS information corresponding in order to the sector of storing in UE sub-district of living in neighboring BS information that information extraction unit is extracted and the memory cell mates, thus definite residing concrete sector of UE; And
Arithmetic element is in order to proofread and correct described RTT measured value according to the radio-frequency channel time delay value of the residing concrete sector of UE.
Beneficial effect of the present invention: under the multi-sector cell situation, make full use of neighboring BS information and discern which concrete sector that UE specifically is positioned at multi-sector cell, extract the radio-frequency channel time delay value of this sector then the RTT measured value is proofreaied and correct, thereby improved the terminal positioning precision and do not increased any network and the terminal cost.
Description of drawings
Fig. 1 is for carrying out the structural representation of Cell ID+RTT location to the UE that is in non-soft handover area in the existing mobile communication system.
Fig. 2 is for carrying out the structural representation of Cell ID+RTT location to the UE that is in soft handover area in the existing mobile communication system.
Fig. 3 is a kind of multi-sector cell networking of the present invention schematic diagram.
Fig. 4 is a kind of multi-sector cell RTT of the present invention measurement update method schematic diagram.
Embodiment
Be illustrated in figure 3 as 1 multi-sector cell networking legend, sub-district 1 is made up of sector A and sector B among the figure, and sector A and sector B have same cell ID Cell ID, are same sub-districts.At the signal common radio-frequency receiving-transmitting passage of inside of base station sector A and sector B, but pass through different feeder lines and antenna separately.Therefore there are T in sector A and sector B The RX channel time delayAnd T The TX channel time delayDifference is mainly because feeder line and antenna difference cause that because antenna difference is very little, actual main delay variation comes the self-feed line difference in length.
Along with after network arrangement finishes, each sector feeder line model and length all are known, because the propagation velocity of signal in specific feeder line is constant, so this T of sector A and sector B The RX channel time delayAnd T The TX channel time delayDifference can be known.Simultaneously, even can not know the feeder line difference in length, T between sector A and the sector B The RX channel time delayAnd T The TX channel time delayDifference also can obtain by test in advance.
If when the RTT that carries out sub-district 1 measures, can know signal, just can accurately proofread and correct the RTT value that obtains in the base band test specifically from sector A or sector B.
After finishing as Fig. 3 network arrangement, the neighboring BS relationship of each sector in the multi-sector cell (the sector A of corresponding diagram 3 and sector B) has also just been determined, their adjacent area is incomplete same, by this adjacent area difference, just can judge further that the UE that is in the multi-sector cell specifically is in (the sector A as sub-district 1 still is sector B) in which sector.
Whether the sub-district of corresponding Cell ID is that multi-sector cell just determines that after network arrangement is finished the neighboring BS relationship of each sector in the multi-sector cell (as the sector A and the sector B of sub-district among Fig. 3 1) can obtain in conjunction with methods such as actual tests by the network planning.More than these information all be kept in advance among the RNC (RadioNetwork Controller, radio network controller).Simultaneously, the radio-frequency channel time delay TRX channel time delay and the TTX channel time delay of non-multi-sector cell are kept among the RNC according to the sub-district in advance, RNC should preserve the radio-frequency channel time delay value of corresponding each sector in multi-sector cell, as should preserve the radio-frequency channel time delay value of sector A and sector B at Fig. 3.
The invention provides a kind of RTT measurement update method of multi-sector cell, its a kind of embodiment specifically may further comprise the steps as shown in Figure 4:
100, RNC selects CELL ID+RTT or other need use the locate mode of RTT measured value information;
101, whether the RNC inquiry has stored the UE metrical information, if then jump to step 103, otherwise enter step 102;
102, UE is initiated paging, make UE transfer to state of activation;
RNC need initiate paging to this UE, make UE from idle condition, as URA_PCH state or IDLE state transitions to state of activation, as the Cell_DCH state.
103, obtain the Cell id information that UE is in;
If RNC does not store the metrical information of UE, so in step 102 after the UE completion status shifts, can report to RNC and shift success message and place cell measurement information, comprise sub-district, UE place CELL id information and neighboring BS information, RNC obtains Cell ID value from the metrical information of UE then.
If RNC has stored the UE metrical information, then can directly obtain the Cell id information that UE is in.
104, judge whether UE is positioned at multi-sector cell, is then to jump to step 106, otherwise enter step 105;
RNC preserves network configuration cases in advance, can determine according to Cell ID whether this sub-district is multi-sector cell.
105, extract the radio-frequency channel time delay value of sub-district: T The RX channel time delay+ T The TX channel time delay, execute and jump to step 109.
106, the neighboring BS information of inquiry UE from metrical information, and the neighboring BS relationship of each sector of multi-sector cell of preserving in advance with RNC mates;
If be multi-sector cell (as Fig. 3 sub-district 1), continue the metrical information of inquiry UE, therefrom extract the neighboring BS information of UE, and the neighboring BS information corresponding with each sector (as Fig. 3 sector A and sector B) of preserving in advance among the RNC mates.
107, determine the concrete sector that UE is positioned at according to matching result;
Determine that according to matching result UE is arranged in which concrete sector (the sector A of sub-district 1 still is sector B), supposes that here matching result is sector A.
108, extract the radio-frequency channel time delay value of sector: T The RX channel time delay+ T The TX channel time delay
109, RTT and UE Rx-Tx Time Difference measure;
RNC initiates RTT at positioning UE to NodeB and measures, and initiates Rx-Tx TimeDifference to positioning UE simultaneously and measures.
110, RTT proofreaies and correct: RTT=RTT Measure-(T The RX channel time delay+ T The TX channel time delay);
Radio-frequency channel time delay value according to the sector A that prestores is proofreaied and correct the RTT measured value: RTT=RTT Measure-(T The RX channel time delay+ T The TX channel time delay).
111, continue the location according to method for selecting;
After obtaining RTT and Rx-Tx Time Difference, determine ToA distance (ToA distance=[(RTT-Rx-Tx Time Difference)/2] * C),, just can further position to UE again according to sector antenna location.
Simultaneously, the present invention also provides a kind of multi-sector cell RTT measurement update system, is used for the RTT measured value is proofreaied and correct, and described system includes radio network controller, and described radio network controller comprises:
Memory cell in order to storage cell attribute information, comprises the neighboring BS information of multi-sector cell attribute information and each sector correspondence, and stores the radio-frequency channel time delay value T of each sector correspondence The RX channel time delayAnd T The TX channel time delay
Information extraction unit is in order to extract UE sub-district of living in neighboring BS information;
Identifying unit, the neighboring BS information corresponding in order to the sector of storing in UE sub-district of living in neighboring BS information that information extraction unit is extracted and the memory cell mates, thus definite residing concrete sector of UE; And
Arithmetic element is in order to proofread and correct described RTT measured value according to the radio-frequency channel time delay value of the residing concrete sector of UE, promptly by formula RTT Measure-(T The RX channel time delay+ T The TX channel time delay) proofread and correct the RTT measured value.
The positive effect that the present invention brings is exactly under the multi-sector cell situation, make full use of neighboring BS information and discern which concrete sector that UE specifically is positioned at multi-sector cell, thereby guarantee that the RTT value is accurately proofreaied and correct, improved positioning accuracy and do not increased any network and the terminal cost.
Explanation is at last, above embodiment is only unrestricted in order to technical scheme of the present invention to be described, although the present invention is had been described in detail with reference to embodiment, those of ordinary skill in the art is to be understood that, can make amendment or be equal to replacement technical scheme of the present invention, and not break away from the spirit and scope of technical solution of the present invention.

Claims (7)

1, a kind of multi-sector cell method that the RTT measured value is proofreaied and correct is characterized in that this method comprises the steps:
A, determine the concrete sector at UE place;
B, initiation RTT measure, and obtain the RTT measured value;
The radio-frequency channel time delay value of C, extraction sector, UE place;
D, come the RTT measured value is proofreaied and correct according to the radio-frequency channel time delay value among the described step C.
2, method according to claim 1 is characterized in that, the radio-frequency channel time delay value of sector, UE place comprises T among the step C The RX channel time delayAnd T The TX channel time delay
In step D, pass through RTT Measure-(T The RX channel time delay+ T The TX channel time delay) computing formula proofread and correct the RTT measured value.
3, method according to claim 1 is characterized in that, comprises also whether the sub-district of judging the UE place is the step of multi-sector cell before the steps A.
4, method according to claim 3 is characterized in that, judges whether sub-district, UE place is that multi-sector cell specifically may further comprise the steps:
Whether a, radio network controller inquiry have stored the UE metrical information, if any metrical information, then directly obtain the CELL ID of UE sub-district of living in; Otherwise UE is initiated paging, and UE transfers to state of activation, and radio network controller obtains the CellID value according to state transitions success message and the place cell measurement information that UE reports;
The Cell id information that b, basis are obtained determines whether sub-district, UE place is multi-sector cell.
5, method according to claim 1 is characterized in that, steps A specifically comprises:
A1, extract the neighboring BS information of sub-district, UE place, and the neighboring BS information corresponding with each sector of preserving in advance in the radio network controller mates;
A2, determine the concrete sector at UE place according to matching result.
6, a kind of multi-sector cell RTT measurement update system is used for the RTT measured value is proofreaied and correct, and described system includes radio network controller, it is characterized in that, described radio network controller comprises:
Memory cell in order to storage cell attribute information, comprises the neighboring BS information of multi-sector cell attribute information and each sector correspondence, and stores the radio-frequency channel time delay value of each sector correspondence;
Information extraction unit is in order to extract UE sub-district of living in neighboring BS information;
Identifying unit, the neighboring BS information corresponding in order to the sector of storing in UE sub-district of living in neighboring BS information that information extraction unit is extracted and the memory cell mates, thus definite residing concrete sector of UE; And
Arithmetic element is in order to proofread and correct described RTT measured value according to the radio-frequency channel time delay value of the residing concrete sector of UE.
7, multi-sector cell RTT measurement update according to claim 6 system is characterized in that described radio-frequency channel time delay value specifically comprises T The RX channel time delayAnd T The TX channel time delay
Described arithmetic element is to pass through RTT Measure-(T The RX channel time delay+ T The TX channel time delay) computing formula proofread and correct the RTT measured value.
CNB2006100618866A 2006-07-31 2006-07-31 Method and system for correcting RTT measuring valve by multi-sector cell Expired - Fee Related CN100455129C (en)

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WO2014075295A1 (en) * 2012-11-16 2014-05-22 华为技术有限公司 Method and device for determining sector where user equipment is located
CN104380140A (en) * 2012-06-14 2015-02-25 爱立信(中国)通信有限公司 Method and apparatus for position determination
CN107079399A (en) * 2014-09-15 2017-08-18 高通股份有限公司 For the enhancing technologies of IEEE 802.11 efficiently positioned
WO2022028252A1 (en) * 2020-08-07 2022-02-10 大唐移动通信设备有限公司 Method and apparatus for correcting transmitting channel delay, and storage medium
CN114521017A (en) * 2022-04-20 2022-05-20 北京度位科技有限公司 Method and device for positioning, electronic equipment and storage medium
WO2022151859A1 (en) * 2021-01-15 2022-07-21 大唐移动通信设备有限公司 Information processing method and apparatus, terminal, and network side device
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US5974057A (en) * 1997-09-30 1999-10-26 Motorola, Inc. Method and apparatus for correcting a measured round-trip delay time in a wireless communication system
US6300905B1 (en) * 1999-10-05 2001-10-09 Lucent Technologies Inc. Location finding using a single base station in CDMA/TDMA systems
CN1298188C (en) * 2002-08-31 2007-01-31 中兴通讯股份有限公司 Location method based on existing communication agreement
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CN104380140A (en) * 2012-06-14 2015-02-25 爱立信(中国)通信有限公司 Method and apparatus for position determination
US10274581B2 (en) 2012-06-14 2019-04-30 Telefonaktiebolaget Lm Ericsson (Publ) Method and apparatus for position determination
WO2014075295A1 (en) * 2012-11-16 2014-05-22 华为技术有限公司 Method and device for determining sector where user equipment is located
CN107079399A (en) * 2014-09-15 2017-08-18 高通股份有限公司 For the enhancing technologies of IEEE 802.11 efficiently positioned
WO2022028252A1 (en) * 2020-08-07 2022-02-10 大唐移动通信设备有限公司 Method and apparatus for correcting transmitting channel delay, and storage medium
WO2022151859A1 (en) * 2021-01-15 2022-07-21 大唐移动通信设备有限公司 Information processing method and apparatus, terminal, and network side device
CN114521017A (en) * 2022-04-20 2022-05-20 北京度位科技有限公司 Method and device for positioning, electronic equipment and storage medium
WO2024060097A1 (en) * 2022-09-21 2024-03-28 北京小米移动软件有限公司 Terminal positioning method and apparatus

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