Summary of the invention
The invention provides the brand-new navigation system in a kind of mobile communications network, be used for calculating and discerning the position of travelling carriage (MS).In addition, the invention provides a kind of permission mobile switching centre (MSC) asks positioning service according to the needs of travelling carriage or network method.
According to an aspect of the present invention, mobile communication system comprises:
(a) at least 3 base transceiver stations (BTS) are used for from the required detected parameters in position of travelling carriage received power increase function (PUF) signal and definite travelling carriage; With
(b) mobile switching centre (MSC) comprises the device that is used for calculating by reception and combine detection parameter location of mobile station.
The present invention is described to a kind of positioning service method of mobile communication system at this in the preferred embodiment mode, this mobile communication system comprises and is connected in the serving base transceiver station (BTS) of the channel of mobile communications, is connected to the mobile switching centre (MSC) of public switched telephone network (PSTN) with the base station controller (BSC) of contiguous at least 2 adjacent BTS, control serving BTS and each the adjacent BTS of serving BTS with BSC that this method comprises the steps:
(a) MSC asks positioning service to BSC;
(b) according to the request for location services of MSC, BSC asks the channel allocation of travelling carriage to each adjacent BTS;
(c) connect the channel of travelling carriage to each adjacent BTS, and ask according to the BSC of step (b), each adjacent BTS sends response signal to BSC;
(d) BSC command service BTS increases function (PUF) signal to travelling carriage request power;
(e) according to the BSC instruction of step (d), serving BTS instruction travelling carriage sends the PUF signal;
(f) according to the instruction of the serving BTS of step (e), travelling carriage sends the PUF signal to the adjacent BTS with each of serving BTS;
(g) calculate the required parameter of location of mobile station by serving BTS by a plurality of PUF input that receiving mobile sends, each PUF signal sends with different time delays;
(h) the adjacent BTS with each of serving BTS reports detected parameter to BSC;
(i) BSC sends the parameter of being reported by the adjacent BTS with each of serving BTS to MSC; With
(j) use detected parameter, MSC calculates the position of travelling carriage; Wherein
The step of request positioning service can be started in the travelling carriage request or when the network operator asks the positional information of travelling carriage;
And wherein, after BSC receives request for location services from MSC, start first timer immediately, and when MSC asks the positioning service of travelling carriage once more or when the positioning service of reporting of mobile station is finished, stop first timer.
According to another aspect of the invention, BSC is at least 2 BTS of request from all BTS that comprise the tabulation of the adjacent BTS of serving BTS, to distribute the channel of travelling carriage in step (b).
According to another aspect of the invention, step (d), promptly the step by BSC command service BTS request PUF signal is to be undertaken by sending the PUF signal message that satisfies the IS-95B standard by BSC to serving BTS.
According to another aspect of the invention, the information about the PUF signal comprises power level interval, the time interval and transmitting time.
According to another aspect of the invention, this method also comprises the step of step that turns back to step (b) when MSC asks the positioning service of travelling carriage once more in first crash time (first timer), ask the channel allocation of travelling carriage to each adjacent BTS, wherein first crash time be defined as from MSC to BSC request positioning service the time be carved into BSC receives the positioning service signal from MSC the moment.
According to another aspect of the invention, this method also comprises the step that stops positioning service when the service that positions owing to MSC request BSC makes MSC not ask the positioning service of travelling carriage in the crash time at first timer once more.
According to another aspect of the invention, step (g) wherein, be that the step that the adjacent BTS with each of serving BTS receives the PUF signal also comprises the steps: if at least one adjacent BTS does not receive the PUF signal after travelling carriage sends the PUF signal in the scheduled time of being determined by second timer, then adjacent BTS discharges travelling carriage and does not receive preassignment channel between the adjacent BTS of PUF signal.
According to another aspect of the invention, this method also comprises when position the step that stops positioning service when service makes MSC ask in the crash time at first timer to stop positioning service owing to MSC request BSC.
The method according to this invention, parameter wherein are the time-delay values of the PUF signal measured in each BTS.
According to another aspect of the invention, step (i) wherein, promptly the step that sends parameter to MSC also comprise when when BSC reports that the number of the BTS of detected parameter is less than or equal to 2 to the step of MSC report fault.
According to another aspect of the invention, step (i) wherein, promptly the step to MSC transmission parameter also comprises such step, if promptly report that to BSC the number of the BTS of detected parameter was less than or equal at 2 o'clock, by the BSC instruction as yet not at least one BTS of the detected parameter of report reconnect to the channel of travelling carriage.
Embodiment
The invention discloses the method that positioning service is provided in the mobile communication system.Before describing conventional method of the present invention, will explain that employed power increases function (PUF) signal and 3 timers in the inventive method.
Power increases function (PUF) signal
In code division multiple access (CDMA) cellular system or personal communication service (PCS) of support as the IS-95B of the air interface between travelling carriage and the base transceiver station, base transceiver station (BTS) can increase function (PUF) signal to travelling carriage request power, and, support the travelling carriage of IS-95B to send the PUF signal according to the request of BTS.
The PUF signal is by the very big power signal of travelling carriage according to the request transmission of BTS.Travelling carriage sends pulse with particular time interval, and wherein this pulse strengthens with the certain power level increment in the given time.Owing to compare with the general transmitted power of travelling carriage, the PUF signal is to send with quite high power level, and therefore, this BTS and adjacent BTS can receive this signal at an easy rate.
3 timers
(1) first timer
Position: base station controller (BSC)
Use: in case this timer is then started in mobile switching centre (MSC) request positioning service immediately, and when this timer from MSC receive positioning service finish message the time, then be stopped.If the first timer meter is full, then BSC stops positioning service.
(2) second timer
Position: base transceiver station (BTS)
Use: appointment then start this timer immediately in case base station controller (BSC) request is believed, and when this timer when travelling carriage receives the PUF signal, then be stopped.If the second timer meter is full, then adjacent BTS notifies this BTS not receive this PUF signal.
(3) the 3rd timers
Position: travelling carriage (MS)
Use: in case receive PUF information and sending PUF signal, then start this timer immediately, be stopped then from serving BTS.If the 3rd timer meter is full, then this travelling carriage determines not send as yet this PUF signal.
With reference to Fig. 1, cell phone navigation system according to the present invention comprises: at least 3 BTS10,11,12, in them each all increases function (PUF) signal from the travelling carriage received power, each BTS also detects the required parameter in position of search travelling carriage, that is to say, BTS receives the PUF signal from travelling carriage, and measures the time that receives the PUF signal, and the measured time is to calculate the necessary parameter value of location of mobile station; Mobile switching centre (MSC) 30, it comprises and being used for by combination through base station controller (BSC) 20 from 3 BTS10 that each parameter that receives in 11,12 is calculated the device of the position of travelling carriage; Location database 32, it and the same location of MSC, the position data that is used to store the travelling carriage that goes out with Management Calculation; Operation maintenance center (OMC), it and the same location of MSC are used to provide single-point control (being the configuration status that the operator provides whole navigation system), control ability, state, alarm, diagnosis and function of reporting; The application processor (AP) 41 of public switched telephone network 40 (PSTN) is used for by obtaining necessary information from location database 32 visit datas, and is responsible for maintenance, configuration and the control of this location.
When travelling carriage was communicated by letter with BTS 10, BTS 10 was called serving BTS.When serving BTS 10 was wanted to learn the position of travelling carriage, this serving BTS 10 sent PUF message by the forward traffic channel that connects travelling carriage and BTS to travelling carriage, with request PUF signal.
If travelling carriage receives PUF message, it just continues to increase the transmission output level in the short time in official hour interval (the 3rd timer), sends the PUF signal that comprises preamble by reverse traffic channel (promptly from MS to BTS) then.
As long as travelling carriage receives PUF message from BTS, then the 3rd timer starts immediately, and stops in the moment that sends the PUF signal by reverse traffic channel.
Be arranged in each transmission PUF message of travelling carriage 3 BTS 10,11,12 on every side and correspondingly receive the PUF signal that sends from travelling carriage.By being divided into two to the time that receives the PUF signal from sending PUF message, each BTS measures each time of delay (being TOA (time of advent)).The position of calculating travelling carriage time of delay that MSC 30 uses each BTS (that is, BTS 10,11,12) to measure then.
Fig. 2 illustrates the reception of PUF signal among the BTS.As shown in Figure 2, travelling carriage 50 is communicated by letter with BTS 10.Serving BTS 10 sends PUF message to travelling carriage 50.After travelling carriage 50 receives the PUF message signale, send PUF signal 15, at this moment, the PUF signal increases to the level of regulation gradually in the preset time interval.
BTS 10 BTSs 11,12 adjacent with it receive this PUF signal.Each BTS record is based on the different time-delay value TDOA (time of advent is poor) of each distance that arrives travelling carriage and radio environment.
Fig. 3 represents with the distance to be the figure of power level of the reception PUF signal that receives of each BTS of function.As shown in Figure 3, travelling carriage 50 sends PUF pulse 1,2,4 (that is, first pulse sends, and second pulse sends at 2ms) by increment continuous time of constant interval when 1ms.In addition, in each continuous time interval, power increases (being 10dBm when being 1ms, is 12dBm during 2ms, is 14dBm during 3ms) with fixing increment.Then, be in the BTS 10 reception PUF pulses 1 of the position of approaching travelling carriage 50 most.But along with the increase of distance, PUF pulse 1 weakens gradually, thereby BTS 11 can not receive the PUF pulse 1 that weakens.Yet, come the next PUF pulse that sends with higher level, i.e. PUF pulse 2, thus BTS 11 can receive PUF pulse 2.Therefore, BTS 12 can only receive the PUF pulse 4 of maximum level.
Each BTS 10,11,12 sends TDOA to MSC 30, with it as time delay to PUF pulse 4 measurements of the peak signal that receives by each BTS.Each BTS also sends the information that is used for the computing network position.Then, MSC 30 adopts the position that the TDOA algorithms calculate travelling carriage 50.Then with the location storage of the travelling carriage 50 that calculated at location database 32.
The invention also discloses a kind of method by mobile switching centre's request positioning service.
Because BTS sends PUF message to travelling carriage, so MSC should ask positioning service to BTS by BSC.BSC is assigned to the Traffic Channel of travelling carriage, thereby each adjacent BTS of serving BTS and this BTS can receive the signal by travelling carriage transmission PUF.
That is to say that when the network operator needs or the user need learn travelling carriage position (when for example travelling carriage is dialled " 911 "), MSC sends request for location services to BSC.Then, BSC by the channel of not communication to BTS that communicates with travelling carriage or the synchronous with it BTS request positioning service of travelling carriage.In case set up forward traffic channel, BTS just sends PUF message by this forward traffic channel to corresponding mobile station.
With reference to the neighbor lists of storing in advance, BSC uses long pseudo noise (PN) code instruction travelling carriage each adjacent BTS on every side of travelling carriage to distribute a channel as travelling carriage, thereby each adjacent BTS can receive the PUF signal that is sent by travelling carriage.If finished the channel allocation of each adjacent BTS, then travelling carriage sends this PUF signal, and BTS receives this PUF signal, sends measured parameter (for example TOA, delay angle, the angle of arrival etc.) to MSC then.
Fig. 4 is the signal transmission flow figure of expression according to the method for the positioning service of request of the present invention mobile switching centre.
When the travelling carriage 50 that communicates by Traffic Channel and serving BTS 10 sends urgent call when (as ' 119 '), perhaps when the network operator asked the positional information of travelling carriage 50, MSC 30 asked positioning service 100 by sending Loc_Svc_rqst through E1 chain road direction BSC 20.
Then, according to the request of MSC 30, send TCE_Asgn by each the adjacent BTS 11,12 to travelling carriage, BSC 20 requested service Channel Elementss specify 110.At this moment, by using the adjacent BTS tabulation that is connected the serving BTS 10 that communicates with travelling carriage 50, BSC 20 is assigned to the channel of two or more adjacent BTS.
Adjacent BTS 11,12 receives the request that the Traffic Channel unit distributes, and the information of use travelling carriage 50 is assigned to the Traffic Channel of travelling carriage 50, and corresponding response message TCE_Asgn_ack is beamed back BSC20 120.
BSC 20 receives response messages from adjacent BTS 11,12, and by sending PUF_msg_rqst to the serving BTS 10 that communicates with travelling carriage 50, command service BTS 10 sends PUF message PUF_msg 130.PUF_msg_rqst comprises the information that will be sent to travelling carriage 50 by BTS 10, the promptly relevant information (as the 2dBm increment, 4dBm increment etc.) and the information in the time interval of relevant transmission PUF signal that increases the level increment of PUF signal.
Serving BTS 10 sends PUF message signale PUF_msg 140 by the Traffic Channel that connects in advance to travelling carriage 50.Travelling carriage 50 sends the PUF signal according to the information that is included in the PUF_msg that receives and responds 150.This PUF message signale comprises power level interval, the time interval and transmitting time etc.
Then, serving BTS 10 and adjacent BTS 11,12 (they each Traffic Channel that links to each other with travelling carriage 50 is all arranged) receive and have the PUF signal that different time postpones.If the one or more BTS among these adjacent BTS 11,12 receive the PUF signal in (promptly being defined by second timer) as yet not during official hour, then BTS discharges Traffic Channel and stops second timer.
That is to say, as long as adjacent BTS just starts second timer at once, and stop this second timer when receiving the PUF signal from travelling carriage from the request that BSC receives channel allocation.
If all BTS 10,11,12 receive the PUF signal, then BTS 10,11,12 sends location parameter such as the time delay that PUF is measured by BSC20 to MSC 30, and MSC 30 calculates the position 160 of travelling carriage according to received location parameter.
At this moment, if the number of BTS of response is less than 2, among for example a plurality of BTS only a BTS because of request for location services Traffic Channel is connected to travelling carriage, then BTS stops to discharge Traffic Channel owing to second timer, so, just can not calculate the position of travelling carriage.As a result, BSC 20 just must be to MSC 30 report faults, perhaps to the not reallocation of at least one BTS requested service channel of reported position parameter as yet.
The BSC 20 that receives Loc_Svc_rqst in step 100 begins to operate first timer.In case BSC receives Loc_Svc_rqst from MSC, just start first timer immediately, and stop at the Loc_Svc_rqst that receives identical travelling carriage from MSC or the moment of Loc_Svc_Complete.
If received the Loc_Svc_rqst of identical travelling carriage 50 from MSC 30 before stopping the first timer operation, then BSC 20 asks channel allocation 170 to adjacent BTS 11,12 once more, and repeating step 110~150.If do not receive Loc_Svc_rqst before the first timer meter is full, then BSC 20 stops positioning service and first timer.
If MSC 30 sends Loc_Svc_Cmpt (being that positioning service is finished) before the first timer operation stops, then BSC 20 discharges by sending the TCE_release command channel to adjacent BTS 11,12, and stops positioning service 180.
Timer is described
Although each timer has been done general description, still come more fully described below with reference to the signal transmission flow figure of Fig. 4.
1. first timer is arranged in BSC, and starts in the moment that receives Loc_Svc_rqst from MSC, and finishes in the moment of Loc_Svc_rqst that receives identical travelling carriage from MSC or Loc_Svc_Complete.
2. second timer is arranged in BTS, and starts in the moment that receives the TCE_asgn that is used for positioning service from BSC, and finishes in the moment that receives the PUF signal from travelling carriage.
3. the 3rd timer is arranged in travelling carriage, and starts in the moment that receives PUF_msg from BTS, and finishes in the moment that sends the PUF signal to BTS.
Fig. 5 represents each flow chart of steps according to the method for the positioning service of the request mobile switching centre of second embodiment of the invention.
As mentioned above, the preferred embodiments of the present invention provide and have use positions service ability based on the PUF signal of IS-95B standard travelling carriage.This method relates to by the request of MSC starting positioning service and the request for location services among the support BSC.Like this, advantage of the present invention does not need the navigation system of separating for the position that can adopt existing general mobile communication system to calculate travelling carriage.
Although describe specific embodiments of the invention with exemplary forms in detail with reference to accompanying drawing above, the present invention is applicable to various variations and replacement form.It should be understood that the present invention is not limited to particular forms disclosed, on the contrary, the present invention falls into aim and all changes in the scope, equivalence and the replacement form that claims limit with covering.