Recently, full electronic switching system is widely used as communication system most, particularly central office switching system.Switching system mainly is to converse by conversation medium access the other user and the other side who resembles telephone set and so on.In addition, switching system provides session services near user by direct connection itself and near user's circuit, and its distance of passing on a message depends on the density of circuit.In addition, switching system adopts remote subscriber module (RSM) thereby the remote subscriber coupled together through trunk line and switching system provides the call treatment service to internal user.
As usual, connect the service that the remote subscriber module of switching system only provides basic function for a plurality of internal users (being generally 512 users) through trunk line, other critical services that resembles call treatment and produce sound equipment and so on then offers internal user by sending to or receive through trunk line from the data that exchange system.
Referring to Fig. 1, there is shown central office switching system 12 and the be connected situation of remote subscriber module (RSM) by trunk line 14.During work, if for example first user's 1 telephone set is in off hook state and dials thereon so that converse with second user 2, then DTMF (dual-tone multifrequency) or pulse signal are just along with this dial action produces.This dtmf signal directly is sent to central office switching system 12., yet pulse signal detects and convert to data-signal by remote subscriber module 10.Data-signal after the conversion sends central office switching system 12 to through trunk line 14.The input terminal call that central office switching system 12 usefulness provide.In addition, central office switching system 12 transmits swap data by the predetermining circuit of being made up of trunk line 14 and remote subscriber module 10 to remote subscriber module 10 according to DTMF that provides or pulse signal, thereby bell signal is received second user 2 of (or sending to) internal user.If second user 2 responds bell signal, central office switching system 12 just forms communication path.
In sum, the DTMF or the pulse signal that connect the internal user generation of remote subscriber module 10 are detected by ready receiver in the central office switching system 12, and the various acoustic signals that internal user produces then offer central office switching system 12.
In above-mentioned prior art, if data are because of trunk line 14 opens circuit or fault does not have correctly to transmit between remote subscriber module 10 and central office switching system, are in off hook state and also can produce dialing tone even then connect the interphone of remote subscriber module 10.Like this, switching system just can not be before the failed trunk line is fixed give connect the failed trunk line provide the call treatment service away from internal user.In addition, if setting up trunk line solves the problems referred to above, then expense may improve unreasonably.
Therefore, the purpose of this invention is to provide a kind of in order to correctly not send central office switching system in data to or to handle the remote subscriber module of Internal call when central office switching system receives.
Another object of the present invention provides a kind of in order to properly not send central office switching system in data to or to handle the method for Internal call when central office switching system receives.
According to first aspect of the present invention, the remote subscriber module that the present invention can handle Internal call comprises following each several part: a controller, in order to when trunk line is in abnormal state, to control the function of exchange between each remote subscriber; A subscriber line circuit is in order to detect remote subscriber's off-hook condition; A tone generator is in order to produce various tones according to exchange interaction under the control of controller; A DTMF receiver in order to detecting dtmf signal and the hub from the remote subscriber, connects the communication path between each remote subscriber in order to according to the control switching of controller the time.
According to another aspect of the present invention, when the method that the present invention handles Internal call comprises the following steps: that trunk line is in abnormal state, detect remote subscriber's off-hook condition by subscriber line circuit; Sending dialled number sound when detecting off-hook condition; Telephone number according to dialing tone receipt of call user generation; If the telephone number received is identical with remote subscriber's telephone number in being stored in remote subscriber's module, then send the sound equipment of this calling of connection; If being in off hook state, called subscriber's telephone set responds this sound equipment then by control circuit hub formation communication path.
Can more clearly understand above and other objects of the present invention, characteristics and advantage from the detailed description of one embodiment of the present of invention being done below in conjunction with accompanying drawing.In the accompanying drawing:
Describe a most preferred embodiment of the present invention below with reference to the accompanying drawings in detail.In the accompanying drawing, same numbering is represented same element.
Referring to Fig. 2, there is shown the remote subscriber module of a most preferred embodiment of the present invention.Among the figure, the whole operation process of controller 110 control remote subscriber modules.The a plurality of internal users 1,2 of subscriber line circuit 112 management ..., n becomes signal that sends to internal user and the interface of receiving from the signal of internal user, and detects the off-hook condition of internal user so that off-hook information is provided for controller 110.Circuit hub 114 is transferred to corresponding part according to the control of controller 110 with subscriber line circuit 112.The trunk line 14 that trunk line part 116 will connect central office switching system 12 is connected to circuit hub 114, and handles the other user in trunk line 14 needed information.Tone generator 118 produces various tone signals under the control of controller 110 circuit hub 114.DTMF receiver 120 receives the dtmf signal of internal user by circuit hub 114.DTMF receiver 120 converts dtmf signal to tentation data, and sends translation data to controller 110.Certainly, circuit hub 114, tone generator 118, DTMF receiver 120 and subscriber line circuit 112 can collect and be contained on the circuit board.
Fig. 3 shows Internal call processing method of the present invention, and this method comprises by trunk line 14 handles the subprogram of normal call state and another subprogram of processing Internal call state.In addition, Fig. 4 also shows in detail the subprogram of Internal call treatment state, and this program comprises the following steps: to produce voice signal according to the situation of internal user; And connect communication path between each internal user according to call request.
During work, controller 110 is examined in step 310, and whether the trunk line 14 that connects central office switching system 12 is in normal condition.If trunk line 14 is in normal condition, controller 110 just carries out general call treatment mode in step 312 through trunk line 14.
Specifically, generally under the call treatment mode of trunk line 14, if the telephone set of internal user is in off hook state, then controller 110 detects the off-hook condition of internal users through subscriber line circuit 112, and sends testing result to central office switching system 12 through trunk line part 116.Central office switching system 12 is given calling party's Sending dialled number sound through remote subscriber module 10.If the calling party is according to dialing tone Outgoing Call number, user's telephone set just produces dtmf signal or pulse signal according to the telephone number of transfering to.Dtmf signal directly sends to central office switching system 12.Pulse signal converts data-signal to after remote subscriber module 10 places detect, send central office switching system 12 to.Central office switching system 12 sends data for trunk line 14 according to dtmf signal or pulse signal, thereby makes remote subscriber module 10 send bell signal for the other side's telephone set, and then is sent/receive speech.What carry out when trunk line 14 is in normal condition is exactly aforesaid operations.
Yet if trunk line 14 is not in normal condition in step 310, controller 110 changes step 314 over to, carries out Internal call processing mode of the present invention, explains detailedly referring to Fig. 4 below.
Controller 110 does not have the telephone set off-hook whether of examining internal user in step 410 by detecting from the off-hook position of subscriber line circuit 112.If the telephone set of internal user is in off hook state, tone generator 118 produces tone signal and give the internal user telephone set Sending dialled number sound of above-mentioned off-hook in step 412 through exchange line hub 114 under the control of controller 110.
When hearing dialing tone, the calling party just transfers to the user's telephone number that will call out.Then, controller 110 is examined in step 414, whether receives the telephone number of dial-out.Here, if user's telephone set is a pulse dialing formula, then the telephone number of Bo Chuing just by means of in the subscriber line circuit in 12 the device of outfit with the detection off-hook condition.Yet, if MFC (multifrequency code) formula of user's telephone set, the telephone number of transfering to is just detected by DTMF receiver 120.If do not receive telephone number in step 414, then controller is just examined in step 416, and whether preset time mistake.If preset time is mistake not, program just turns back to step 414.But as if preset time mistake, controller 110 just thinks that the calling party slings telephone set (or not hanging up properly machine) unintentionally for a long time.So sound generator 118 produces mobile phone howl toot sound in step 418 under the control of controller 110.
Yet, if receive telephone number in step 414, the telephone number that controller 110 is just received step 420 analysis.That is, controller 110 is compared the telephone number of receiving with the intercommunication phone number of storage, and whether the telephone number of receiving with judgement is identical with the telephone number of one of them internal user.Controller 110 is examined in step 422, and whether the telephone number of receiving is the internal user telephone number.If not controller 110 is just judged the calling of this calling for issuing another exchange through central office switching system 12 in step 424.Then, because trunk line 14 is not in normal condition, thereby produces the trunk line Congestion Tone under the control of tone generator 118 control pillars 110, the notification call user, trunk line 14 can not be used at present.Trunk line Congestion Tone via line hub 114 and subscriber line circuit 112 send the calling party to.If in step 422, the telephone number of receiving is the internal user telephone number, and then controller 110 is just examined the user in step 426 and whether is in busy state.If called user is in busy state, tone generator 118 just produces busy tone in step 428 under the control of controller 110.But if called user is not in busy state, the ring generator plate just sends bell signal in step 430 to called user, and tone generator 118 sends ring-back tone in step 432 to the calling party.Controller 110 is examined in step 434, and whether the user has plucked telephone set when hearing bell signal.If not so, then whether examine the calling party with the telephone set on-hook in step 436.If calling party's telephone set does not have on-hook, program just turns back to step 434.But if called subscriber's telephone set is in off hook state in step 434, controller 110 just connects communication path at step 438 control circuit hub 114.
Carry out the Internal call processing mode, if out of order trunk line 14 has been fixed, switching system just carries out general call treatment through trunk line 14 automatically.
In sum, remote subscriber module of the present invention as can be known can improve calling ratio of success, thereby improves the service quality of call treatment.
Above-mentioned most preferred embodiment only is for example, in order to application of the present invention and manufacture process to be described.The experts in present technique field can carry out customary modification to the foregoing description.The present invention is not limited to the foregoing description, but is subjected to the restriction of appended claims.