优先接入和信道指配用户优先接入方法
Technical field The invention relates to the field of wireless communication, in particular to a realize PACA (Priority Access and Channel Assignment priority access and channel assignment) user priority access method of the system. Background technology Master mobile phone user, is called, needs to occupy the radio channel resources and ground circuit resources, wherein the ground circuit resources allocated by the mobile switching center MSC, by the base station radio channel resource allocation BSC control system, if there are no distributed to the corresponding resources, the call cannot be established. For some special user (such as the military in the high-level user), the need is not enough resources can also ensure its opening of the telephone. In the prior art is realized in accordance with the protocol of the user priority access. When the mobile phone calling access is requested, the base station control system (BSC) check resource status, cm service request structure ( Req Service cm) message informs the mobile switching center MSC. Check message to the mobile switching center MSC parameter, found insufficient resources of the wireless channel, and the user signing PACA service, structure PACA Command message to notify the base station control system BSC, MSC mark at the same time to the user (user has in the BSC queuing). The base station control system after the BSC PACA Command message received, the queue PACA user. Checking a wireless channel resources BSC, when the available channel time, from a queue PACA in the highest level of user identification, message notification to re-initiate the initial call request of the mobile phone, to access. When the base station control system found BSC PACA user's queue is changed, the mobile switching center MSC need to inform the user of the cancellation mark. When the mobile switching center MSC the mark found user information (state or position) is changed, but also to inform the base station control system a user from BSC deleted in the queue. PACA first calling user-initiated, flow as shown in Figure 1: When the user when the caller initiates service request, the base station control system for checking a wireless channel resources BSC, set up the corresponding wireless environment and resource parameter ( and Environment Resources Radio), through the cm service request message (cm Req Service) informs the mobile switching center MSC the user request access; Mobile switching center MSC checking a wireless environment and a resource parameter ( and Resources Environment Radio), found that the available radio channel resources, and the user signing PACA service, the base station control system message notification PACA Command user is BSC PACA user; The base station control system after the BSC PACA Command message received, the queue user PACA, then through PACA Command ACK message informs the mobile switching center MSC; Mobile switching center MSC after Command PACA ACK message received, a flag is set, recording PACA user has in the base station control system to the BSC; When the base station control system found BSC resources idle wireless channel, taken out from the queue PACA high-level of the user, notify the user to re-initiate the initial call request, access. BSC base station control system initiating user PACA as shown in Figure 2 the change of state process: When the base station control system finds that the user state change BSC (user termination failure of initial calling or BSC), the base station control system from the BSC delete users in the queue, the message notification Update PACA mobile switching center MSC; Mobile switching center MSC Update PACA the received message, the user of the cancellation mark. Mobile switching center MSC the initiating user PACA as shown in Figure 3 the change of state process: When the MSC the mark found PACA information changes of the user (such as user roaming, the user re-PACA initial call, MSC-side fault, etc.), the mobile switching center MSC to the BSC informs the base station control system modify PACA information of the user; BSC base station control system after receiving the message, the user is deleted from the queue, then return the acknowledgement message. A shortcoming of the prior art: 1, if the ongoing call of the mobile user is not active for finishing the communication, the user can not access PACA; 2, PACA the user queue BSC base station control system, waiting for the other user to end the call releasing resources, access speed is slow; 3, due to the realization of the procedure is complicated, there is no agreement do PACA the flow. The content of the invention In response to the shortcomings in the above-mentioned prior art, the present invention provides a method for user preferential access PACA, the system resource is not enough, PACA the user can guarantee timely access. A of the present invention user PACA priority access method, comprising: Grading the user; When the wireless channel resources and/or circuit is not enough resources, forcibly remove the low-level user-link, the calling or called PACA release user priority access of resources. When the wireless channel is not enough resources, by a mobile switching center MSC selection and PACA user same district demolishing the low-level user; control system can be selected by the base station the BSC PACA user same district demolishing the low-level user. When the circuit is not enough resources, by a mobile switching center forcibly remove the low-level user-link. The remove the low-level user-link, the user priority access PACA, comprising the following steps: When the PACA when the user initiated service request, the base station control system checks the radio channel resources, set up the corresponding wireless environment and resource parameter ( and Environment Resources Radio), sent service request message informs the mobile switching center; Mobile switching center after receipt of the service request message, check the resource parameter ( and Radio Environment Resources), if there is no available wireless channel resources, the mobile switching center service disable flag, PACA user to the small area is the same as the ordinary user or low level access request of the user; if the mobile switching center can find that there is no ground circuit for the resource, then the mobile switching center service disable flag is set, user PACA to the base station control system is the same as the ordinary user or low-level user's access request; Mobile switching center forcibly remove the one and the same small area user PACA the ordinary user or low-level user-link, after the completion of demolishing, sends the assignment request message to notify the base station control system for wireless channel assignment, release the wireless channel resource is occupied; The base station control system takes up the resources of the wireless channel, sends the assignment complete message informs the mobile switching center assignment completed, the user has been successfully access; Mobile switching center after receipt of the assignment complete message, the service disable flag is cancelled. The forcibly remove the low-level user-link, the user priority access PACA, can also include the following steps: When the user initiates a service request, the base station control system directly sends a service request message to the mobile switching center; Mobile switching center after receipt of the service request message, sends assignment request message to the base station control system, wireless channel assignment; If the base station control system found that the available radio channel resources, with distribution failure message informs the mobile switching center; Mobile switching center after receipt of the assignment failure message, setting service disable flag; and then forcibly remove PACA user with a small area is the same as the ordinary user or low-level user-link; and after completion, the occupied circuit resources, the assignment request message to notify the base station control system for wireless channel assignment, release the wireless channel resource is occupied; The base station control system after successful wireless channel resource is occupied, sends the assignment complete message informs the mobile switching center assignment completed, the PACA user has successfully accessed; Mobile switching center after receipt of the assignment complete message, the service disable flag is removed, allowing the ordinary subscriber access request. On the pair of the calling subscriber, the level of the calling subscriber is from high to low is divided into: the emergency call user PACA, the normal user for emergency call, Conference call user participation PACA, ordinary call user participation PACA, ordinary user of the Conference call, the normal user for ordinary call. Another kind of this invention PACA user priority access method, comprising: user reserved resource to PACA, when the user requests access PACA, if the common resources has been used up, then the reserved resources for access. The reserved resources comprises a radio channel resources and/or the circuit resources. Using the method of the invention, when the resource is not enough, the user does not use PACA to the BSC, direct access, the access speed is fast, can meet special user the operational requirements of the particular situation. Figure description Figure 1 is a signal flow chart of the prior art while in initial user PACA, BSC and between MSC; Figure 2 is PACA user state change flowdiagram of initiated by the BSC in the prior art; Figure 3 is PACA user state change flowdiagram of initiated by the MSC in the prior art; Figure 4 is the invention priority access method for one of the process; Figure 5 is the invention priority access the second process. Specific embodiments The invention adopts the method of forcibly remove the link is not enough resources of user access PACA: that is, when the user requests access PACA, do not have enough resources, the low-level user's ongoing call, the resource released by the user to occupy PACA, access. First mobile switching center MSC according to the main, the called user information for each call rating. For example: the call level, from high to low is divided into: the emergency call user PACA, the normal user for emergency call, Conference call user participation PACA, the participation of PACA ordinary call, Conference call normal user for, the normal user for ordinary call. When the user desires access PACA, there is no available resources (ground circuit resources or wireless channel resource) time, a low-level select MSC of demolishing the call. If it is ground circuit insufficient resources, the selection and control system of the same base station user PACA low level of demolishing the talking of the user. If the wireless channel is not enough resources, selection and PACA user same district of the low-level users of demolishing the talking. If ground circuit and wireless channel resources are not sufficient, selection and PACA user same district demolishing the low-level user. PACA and the user-initiated after the completion of the assignment request message, the terrestrial circuit occupying the release of the resource and radio channel resource. In order to avoid release of resources occupied by the ordinary user, after the forced disconnecting the call, the service need to set up corresponding prohibition of the sign. Ground circuit resources is not enough, the user is provided with the same base station control system PACA the service disable flag (BSC). When the wireless channel is not enough resources, the same is provided with user PACA the service disable flag small area. At this time further received the same cell (or BSC) the ordinary user of the access request of the common call, rejected. Common user-initiated emergency call cannot be refused. When the successful user PACA, the occupied ground circuit after the resource and radio channel resources, the service disable flag is cancelled. Figure 4 of the present invention shown the priority access method for a specific procedure, see Figure 4, when the user when the caller initiates service request, the base station control system for checking a wireless channel resources BSC, set up the corresponding wireless environment and resource parameter ( and Environment Resources Radio), Req Service the cm service request message informs the mobile switching center MSC, which the user desires access. Mobile switching center MSC the received message Req Service cm, inspection parameters Resources Radio Environment and, if there is no available wireless channel resources, and the user signing PACA service, the mobile switching center MSC service disable flag is set, user PACA to the same small area with the ordinary user's access request. If there is no available ground circuit resources, to MSC PACA user to flag is set the base station control system is the same as the ordinary user's access request. Then MSC user PACA with selecting a small area is the same as the ordinary user of the ongoing conversation, demolishing carried out, and after completion, Req Assignment sends the assignment request message to BSC informs the base station of the control system of the wireless channel assignment, release the wireless channel resource is occupied. BSC base station control system after successful wireless channel resource is occupied, Complete Assignment sends the assignment complete message informs the mobile switching center MSC assignment completed. Mobile switching center MSC Assignment Complete received the assignment complete message, the service disable flag is cancelled. Priority access method of the present invention can process as shown in Figure 5, the flow and the Figure 4 process similar, different is that a base station control system of the transmitting BSC Service Req message before the cm, the radio channel resources to perform the judgment. Mobile switching center MSC the received service request message Req cm after Service, according to the normal procedure for sending message Assignment Req BSC base station control system for wireless channel assignment. BSC base station control system examination revealed no available wireless channel resource, a failure message replaces Assignment Failure informs the mobile switching center MSC, the user's assignment failure. Mobile switching center MSC Failure Assignment after receipt, if the user signs the PACA service, the mobile switching center MSC corresponding service disable flag is set. Then MSC user PACA with selecting a small area is the same as the ordinary user of the ongoing conversation, demolishing carried out, and after completion, the occupied ground circuit resources, Assignment sends the assignment request message notification Req BSC base station control system for wireless channel assignment, release the wireless channel resource is occupied. BSC base station control system after successful wireless channel resource is occupied, Assignment Complete the message informs the mobile switching center MSC assignment completed. Mobile switching center MSC Complete Assignment the received message, of the cancellation, allowing the ordinary subscriber access request. When the called user as when PACA, if the wireless channel is not enough resources, or ground circuit insufficient resources, demolishing also ordinary user of the ongoing call, resources released by user to occupy PACA, access. Completion of demolishing by the MSC. And the BSC can also be supported by the MSC to realize and PACA access. When the resource is not enough, the user access PACA, if it is ground circuit insufficient resources, by the MSC selects a low-level users demolishing the talking. If it is not enough resources of the wireless channel, the BSC for demolishing base station control system. After completion and, release the user to occupy PACA access of resources. The priority access can also be user PACA to the base station control system reserved BSC resources of the wireless channel, the mobile switching center MSC of the ground circuit resources reserved method to realize. The call of the ordinary user reserved resources cannot be occupied. When the user access PACA, if the common resources has been not enough, the reserved resources to user PACA, access. If the PACA user will not have any reserved resources, and then initiates the procedure. The method of the present invention is suitable for CDMA system and GSM system. Of the above, preferred for this invention only the specific embodiment, but the scope of protection of the present invention is not limited to this, any familiar with the technical field of the invention the technical staff within the technology revealed, can be easily imagined that the change or replacement, should be covered in the scope of protection of the invention. Therefore, the scope of protection of the invention should be to the right to the protection range. A method for implementing priority access of PACA users includes: makes classification for users; when the resources of wireless channel or circuit are not enough, dismantles the link of low grade user, makes priority access to the released resource for the PACA calling or called user. The method can make the PACA user no need to queue in BSC, and can meet special user' requirement. 1, a priority access and channel assignment ( and Access Priority Channel Assignment PACA) user priority access method, comprising: Grading the user; When the wireless channel resources and/or circuit is not enough resources, remove the low-level user-link, the calling or called PACA release user priority access of resources. 2, PACA user priority access method according to Claim 1, characterized in that when the wireless channel is not enough resources, by a mobile switching center selection and PACA user same district the low-level user, or by the base station control system remove the same small region of the low-level users of the link. 3, PACA user priority access method according to Claim 1, characterized in that when the circuit is not enough resources, by the mobile switching center links to remove the low-level users. 4, according to Claim 1, 2 or 3 said PACA user priority access method, characterized in that the removal of the low-level users link, the user priority access PACA, comprising the following steps: When the PACA when the user initiated service request, the base station control system checks the radio channel resources, set up the corresponding wireless environment and resource parameter ( and Environment Resources Radio), sent service request message informs the mobile switching center; Mobile switching center after receipt of the service request message, check the resource parameter ( and Radio Environment Resources), if there is no available wireless channel resources, the mobile switching center service disable flag, PACA user to the small area is the same as the ordinary user or low level access request of the user; if the mobile switching center can find that there is no ground circuit for the resource, then the mobile switching center service disable flag is set, user PACA to the base station control system is the same as the ordinary user or low-level user's access request; Mobile switching center forcibly remove the one and the same small area user PACA the ordinary user or low-level user-link, after the completion of demolishing, sends the assignment request message to notify the base station control system for wireless channel assignment, release the wireless channel resource is occupied; The base station control system takes up the resources of the wireless channel, sends the assignment complete message informs the mobile switching center assignment completed, the user has been successfully access; Mobile switching center after receipt of the assignment complete message, the service disable flag is cancelled. 5, PACA user priority access method according to Claim 4, characterized in that said forcibly remove the low-level user-link, the user priority access PACA, comprising the following steps: When the user initiates a service request, the base station control system directly sends a service request message to the mobile switching center; Mobile switching center after receipt of the service request message, sends assignment request message to the base station control system, wireless channel assignment; If the base station control system found that the available radio channel resources, with distribution failure message informs the mobile switching center; Mobile switching center after receipt of the assignment failure message, setting service disable flag; and then forcibly remove PACA user with a small area is the same as the ordinary user or low-level user-link; and after completion, the occupied circuit resources, the assignment request message to notify the base station control system for wireless channel assignment, release the wireless channel resource is occupied; The base station control system after successful wireless channel resource is occupied, sends the assignment complete message informs the mobile switching center assignment completed, the PACA user has successfully accessed; Mobile switching center after receipt of the assignment complete message, the service disable flag is removed, allowing the ordinary subscriber access request. 6, PACA user priority access method according to Claim 1, characterized in that the call to the user for classification, the level of the calling subscriber is from high to low is divided into: the emergency call user PACA, the normal user for emergency call, Conference call user participation PACA, ordinary call user participation PACA, ordinary user of the Conference call, the normal user for ordinary call. 7, a kind of PACA user priority access method, comprising: user reserved resource to PACA, when the user requests access PACA, if the common resources has been used up, then the reserved resources for access. 8, user priority access method according to Claim 7, characterized in that the reserved resources comprises a radio channel resources and/or the circuit resources.