CN1844948A - Positioning method based on distributed antenna - Google Patents

Abstract

The invention relates to a positioning method based on distributed antenna system (DAS), belonging to the wireless communication technique. Wherein, building a distributed antenna system in the wireless communication system; using the combination between the positioning of distributed antenna station and the positioning of network center; arranging positioning module in the processing station; the distributed antenna receives and transmits the signal of movable terminal; the positioning module calculates the wave reach time TOA and the wave reach angle AOA between the movable station and the antenna; judging the type of transmit antenna and the area of movable terminal; using relative arithmetic module, and using different positioning methods to realize the accurate positioning on the movable terminal. The invention can overcome the defects of non-distributed antenna station that worse received signal, and few stations that can receive the signal of movable stations at one time. The invention can be used to position the terminals as movable communication telephone, vehicle terminal and portable computer.

Description

Localization method based on spaced antenna

Technical field

The present invention relates to wireless communication technology, relate in particular to mobile terminal positioning method in wireless communication system/network.

Background technology

Wireless location technology is the technology of an extensive application prospect, and various services based on mobile terminal locations are as the charging based on location of mobile station, intelligent transportation, personnel's automobile navigation, network planning and optimization design, emergency alarm services etc. all need the localization method of precise and high efficiency.Chang Yong wireless location method mainly is based on mobile location method (GPS, GLONASS, Galileo etc.) and based on mobile communications network localization method (E-OTD, OTDOA-IPDL etc.) now.

The localization method based on hand-held set that with GPS is representative can provide high orientation precision, but this satellite-based targeting scheme has following shortcoming: must add cartridge chip at handheld terminal, make equipment complicated, increase user cost; Need transfer table to carry out computing, the transfer table power consumption is bigger; In indoor and urban environment satellite-signal serious shielding, be difficult to successfully location.

Utilize existing mobile communication equipment based on the positioning system of existing communication network, need not increases extras in terminal, only needs the upgrading by base station software or hardware, can increase positioning function.3GPP also proposes to be applied in the multiple-base station positioning method in the third generation Mobile Communication communication system, sees document (3GPP TS 22.071,3GPP TS Group Services and System Aspects; Location Services (LCS); ServicesDescription-stage 1.).This localization method needs the base station more than three can receive the signal of portable terminal emission.And estimate that accurately ripple reaches the time (TOA:Time of Arrival/TDOA:Time Differenceof Arrival) and ripple reaches angle (AOA:Angle of Arrival).But because the wireless communication signals communication environments is changeable, be subjected to multipath, multiple access disturbs and the influence of NLOS communication environments, may the receiving mobile signal apart from transfer table base station far away, and can not get enough base stations and participate in the location, and can't successfully locate.

Distributing antenna system (DAS:Distributed Antenna System) proposes for signal covering and the capacity problem that solves indoor and complicated urban environment.Distributing antenna system extensively distributes a plurality of small size antennas, and by optical cable, concentric cable etc. link to each other antenna with the processing base station, by handling the signal transmitting and receiving that all antennas of control and treatment are unified in the base station.In the DAS system, a plurality of antennas are distributed in the diverse location in a zone, and it is the cellular cell at center with the base station that the virtual subdistrict of customer-centric has replaced traditional.System is defined as its antenna that service is provided set according to each mobile subscriber position.

Summary of the invention

The present invention proposes a kind of localization method based on spaced antenna, utilize location, spaced antenna base station and network center's positioning combination, non-distributed antenna base station receiving mobile dtr signal before overcoming, the problem of the base station of energy receiving mobile signal less (1-2) simultaneously; It is good that spaced antenna and terminal room are propagated sighting distance, can obtain high orientation precision by basic location algorithm.

Technical scheme of the present invention is: set up distributing antenna system in wireless communication system/network, measure the geographic position of antenna, and its location parameter is kept in the respective handling base station data storehouse; End is provided with localization function module in the processing base station; Antenna transmitting mobile terminal positioning request signal; The ripple that the base station end calculates between portable terminal and forwarding antenna reaches time T OA and Bo Da angle AOA, if antenna end is used smart antenna (SA:Smart Antenna), reach time and Bo Da angle by handling the base station localization function module according to ripple, adopt the single antenna mode to estimate terminal location; If antenna end is used omnidirectional antenna, then handle the base station according to receiving three the strongest terminal signalings that antenna received of portable terminal signal in this base station, carry out TOA, AOA and estimate, utilize TOA, the AOA value estimated, call respective algorithms and calculate the mobile terminal locations coordinate.When Location Request can not be finished in single base station, the base station links to each other with Gateway Mobile Location Center, Gateway Mobile Location Center receives portable terminal positioning request signal and the corresponding ripple transmitted at least two base stations and reaches the time, satisfy positioning requirements if receive quantity of information, the centre of location is called many combination of antennas location algorithm and is calculated portable terminal

Current location

The present invention utilizes location, spaced antenna base station to combine with network center location (many base stations cooperate the location), and the performance advantage of spaced antenna, non-distributed antenna base station receiving mobile dtr signal before overcoming, the less problem in base station of energy receiving mobile signal simultaneously; Defectives such as it is far away to have solved traditional orientation distance, and positioning error is bigger.

Description of drawings

Fig. 1: represented spaced antenna localization method process flow diagram

Fig. 2: provided the distributing antenna system structural representation of location down

Embodiment

In mobile communications network, set up distributing antenna system, measure the geographic position of antenna, and its location parameter is kept in the processing base station data storehouse; End is provided with localization function module in the processing base station; Handle the base station by optical fiber, spaced antenna links to each other under concentric cable etc. and this base station, the transmitting and receiving of a plurality of antennas of far distance controlled and terminal room signal; If antenna end is used smart antenna (SA:SmartAntenna), then by antenna receiving mobile signal, the portable terminal signal is sent to handles the base station and calculate that ripple reaches the time (TOA) and ripple reaches angle (AOA), reach time and Bo Da angle by handling base station end localization function module according to ripple, adopt single base station single antenna locator meams to estimate terminal location.If antenna end is used omnidirectional antenna, then handle the base station according to wherein receiving three the strongest terminal signalings that antenna transmitted of mobile station signal, carry out TOA, AOA and estimate, utilize TOA, the AOA value estimated, call respective algorithms and calculate the location of mobile station coordinate.

Wherein localization process functions of modules in base station is as follows: according to the mobile station signal that antenna receives, estimate that ripple reaches time and Bo Da angle; Judge whether this base station has enough TOA can be used to locate computing; According to aerial position and TOA or AOA, call related algorithm and calculate location of mobile station.

The concrete positioning flow of portable terminal is as shown in Figure 1:

1. portable terminal sends request signal, to the server requests terminal location;

2. spaced antenna receiving mobile signal, by optical cable, repeater etc. pass to mobile station information and handle the base station;

3. end localization function module in base station judges that the antenna of transmitting mobile station signal is smart antenna or omnidirectional antenna, determine that portable terminal is in the single base station coverage still in the zone that be responsible for jointly two even a plurality of base station, base station end localization function module reaches angle AOA and Bo Da time T OA according to the ripple that signal characteristic calculates between transfer table and antenna;

4. when the antenna of transmitting mobile station signal is smart antenna, reach time and Bo Da angle, adopt single base station single antenna locator meams to estimate mobile terminal locations according to ripple;

5. when the antenna that detects the forwarding mobile station signal is omnidirectional antenna, adopt many antennas to cooperate locator meamss to determine the location of mobile station coordinate.

As shown in Figure 2, UE is subscriber terminal equipment (transfer table); BS1 and BS2 are that two distributing antenna systems are handled the base station; Suppose that each processing base station is provided with four antennas (Antenna); GMLC is a Gateway Mobile Location Center; Area A and Area B are respectively base station BS 1 individual responsibility zone and base station BS 1 and the zone that BS2 is responsible for jointly, when transfer table is in zones of different, adopt different locator meamss to position.

● single base station single antenna location

When being in single base station BS 1, is responsible in the regional Area A user terminal (UE), and in the smart antenna overlay area time, mobile station signal is transmitted by smart antenna, aerial position coordinate parameters in the database is called in the base station, according to the signal characteristic value, calculate ripple and reach time, Bo Dajiao, localization function module call formula 1 directly estimate the present present position of transfer table coordinate (x, y)

$\left\{\begin{array}{c}x=X+\mathrm{c\τ}\cos \mathrm{\α}\\ y=Y+\mathrm{c\τ}\sin \mathrm{\α}\end{array}\right.$ Formula 1

Wherein α is Bo Dajiao, and (X Y) is the antenna present position, and (x y) is the location of mobile station of estimating.

● many antennas cooperate the location

When the antenna end of transmitting mobile station signal does not adopt smart antenna, but when adopting omnidirectional antenna, adopt many antennas to cooperate the positioning mobile station position coordinateses.

1. the many antennas in single base station cooperate localization method

When transfer table is in regional as shown in Figure 2 Area A, when transfer table sends Location Request, whether localization function module is judged has enough omnidirectional antennas to transmit this transfer table request signal (many Antenna Positioning algorithm need have at least 3 same base stations of sky alignment to transmit mobile station signals) in the affiliated antenna in this base station, handle the mobile station signal that the base station receiving antenna is transmitted, extract the mobile station signal of three antennas forwardings that wherein forward signal is the strongest, call the position coordinate parameters of the respective antenna of storing in the database, with and the mobile station signal eigenwert transmitted, calculate corresponding ripple and reach time T OA, AOA can adopt conventional algorithm calculating transfer table current locations such as many combination of antennas location algorithm.

This moment, the base station need not to set up contact with Gateway Mobile Location Center (GMLC).

2. many base stations cooperate location (network center location)

When single base station information quantity not sufficient, in the time of can't finishing the location, handle the base station and relevant information must be passed to the centre of location, gather and judged whether that other antenna for base station receive mobile station signal by the Gateway Mobile Location Center information of carrying out, when if two or more base stations have the enough antenna number that satisfy location condition to transmit mobile station signal, by position coordinates and the corresponding TOA calculating transfer table current position coordinates of gateway Mobility Center according to forwarding antenna.

As shown in Figure 2, when transfer table is in distributing antenna system juncture area Area B, transfer table is in the zone of base station BS 1 and the covering of BS2 intersection, base station BS 1 has only two antennas can receive mobile station signal, this base station localization function module judges that the antenna number of transmitting mobile station signal does not reach the requirement of location, single base station, handle the base station promptly according to the transfer table characteristic information, the information calculations such as position coordinate parameters of the antenna of forward signal are transmitted the respective antenna of mobile station signal and the TOA between transfer table, AOA, and with Location Request, TOA, parameters such as AOA and aerial position coordinate pass to Gateway Mobile Location Center GMLC, whether GMLC detects also has other base stations to transmit the position coordinates of this mobile position estimation request and forwarding antenna thereof, corresponding TOA, parameters such as AOA, whether GMLC judge to receive quantity of information satisfies positioning requirements and (has at least 3 antennas to transmit this transfer table request signal and corresponding TOA is arranged, AOA), when meeting the demands, call many combination of antennas location algorithm by the centre of location and calculate the transfer table current position coordinates, and be located the result and give customer mobile terminal by one of them base station feedback.

The calculating of many combination of antennas location algorithm can be adopted the taylor series method of development of TOA, according to time weight centroid method (TWC), estimates a Position Approximate (x according to AOA+TOA ₀, y ₀), as the initial position of the taylor series method of development, carry out Taylor expansion at initial position, to ignore the above component of second order and carry out recursive operation, final operation result promptly is the current position coordinates of transfer table.Also can adopt other conventional algorithms to find the solution mobile terminal locations.

The localization method that the present invention proposes based on spaced antenna, it is good that spaced antenna and terminal room are propagated sighting distance, and the single antenna location still is that many combination of antennas location all has good positioning performance, along with the popularization of spaced antenna, higher use value is arranged.

Claims (4)

1, a kind of localization method based on distributing antenna system is set up distributing antenna system in cordless communication network, it is characterized in that: utilize location, spaced antenna base station to locate the localization method that combines with network center, realize the location to portable terminal.

2, method according to claim 1, it is characterized in that: described localization method specifically comprises: end is provided with localization function module in the processing base station, spaced antenna receives, the transmitting mobile terminal signal, the ripple that localization function module is calculated between transfer table and antenna reaches time T OA and Bo Da angle AOA, judge forwarding antenna type and portable terminal zone of living in, call the respective algorithms module, adopt the accurate location of different localization methods realizations portable terminal.

3, method according to claim 2 is characterized in that: when forwarding antenna is smart antenna, adopt single base station single antenna localization method; When forwarding antenna is omnidirectional antenna,, adopt single base station many Antenna Positioning method if portable terminal is positioned at single base station range; If portable terminal is positioned at the zone that a plurality of base stations intersection covers, adopt many base stations many Antenna Positioning method.

4, method according to claim 3, it is characterized in that: described single base station many Antenna Positioning method comprises the steps: that further localization function module judges whether this base station has enough omnidirectional antennas to transmit this portable terminal positioning request signal, extract the signal of three antennas forwardings that wherein the transmitting mobile terminal signal is the strongest, call the position coordinate parameters of the respective antenna of storing in the database, calculate corresponding TOA, AOA, call many combination of antennas location algorithm and determine the portable terminal current location; Described multiple-base station positioning method comprises: Gateway Mobile Location Center receives portable terminal positioning request signal and the corresponding ripple transmitted at least two base stations and reaches the time, satisfy positioning requirements if receive quantity of information, the centre of location is called many combination of antennas location algorithm and is calculated the portable terminal current location.

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