Patent Publication Number: US-2013250758-A1

Title: Base station, wireless end device, and transmission barring methods thereof

Description:
PRIORITY 
     This application claims the benefit of U.S. Provisional Application Ser. No. 61/615,213 filed on Mar. 24, 2012, which is hereby incorporated by reference in its entirety. 
    
    
     FIELD 
     The present invention relates to a base station, a wireless end device, and transmission barring methods thereof; more particularly, the present invention relates to a base station, a wireless end device, and transmission barring methods thereof for dealing with data transmissions when a special event (i.e. a event that may cause a huge amount of data transmission) happens or is going to happen. 
     BACKGROUND 
     A conventional wireless communication network  1  is illustrated in  FIG. 1 , which comprises a core network  11 , two base stations  131 ,  133 , and a plurality of wireless end devices  151 ,  153 ,  171 ,  173 . The wireless communication network  1  may conform to Long Term Evolution (LTE) standard, Worldwide Interoperability for Microwave Access (WiMAX) standard, or other wireless communication standard that is familiar to people ordinary skilled in the art. 
     The base stations  131 ,  133  are electrically connected to the core network  11 . The wireless end devices  151 ,  153  are in the coverage  12  of the base station  131 , while the wireless end devices  171 ,  173  are in the coverage  14  of the base station  133 . Among the wireless end devices  151 ,  153 ,  171 ,  173 , the wireless end devices  151 ,  171  are user equipments (e.g. mobile phones) and the wireless end devices  153 ,  173  are delay tolerant devices (e.g. smart meters) that simply periodically transmit collected data to the core network  11  via the base stations  131 ,  133 . 
     When an emergency event (e.g. a disaster like earthquake and tsunami) happens, huge amount of uplink data (e.g. emergency calls and/or emergency text messages from the wireless end devices  151 ,  171  to other wireless end devices via the base stations  131 ,  133 , and the regularly collected data from the wireless end devices  153 ,  173  to the core network  11  via the base stations  131 ,  133 ) are transmitted expectedly in the wireless communication network  1 . 
     Huge amount of uplink data transmissions usually causes the base stations  131 ,  133  and/or the core network  11  overload. Specifically, random access channel (RACH) processing resources at the base stations  131 ,  133  will be impacted, which may result in discard of the messages for attachments (e.g. scheduling information (e.g. Msg3 in the LTE standard) transmission failure). The consequence of which is that some of the wireless end devices  151 ,  153 ,  171 ,  173  may not be able to attach to the base stations  131 ,  133  and/or to make emergency calls. 
     Moreover, for the wireless end devices  151 ,  153 ,  171 ,  173  that have attached to the base stations  131 ,  133 , some of them may be in the idle mode. For the aforementioned kinds of wireless end devices  151 ,  153 ,  171 ,  173 , processing resources for idle-to-active signals and/or re-registering signals at the core network  11  will be impacted. For example, S1-AP message and/or non-access stratum (NAS) message may be discarded. The consequence of which is that some of the wireless end devices  151 ,  153 ,  171 ,  173  cannot turn into the active mode from the idle mode and/or re-register to the core network  11 . 
     In addition to the problem of overload, huge amount of uplink data transmissions may also cause intolerable transmission delays, packet loss, or even service un-availability (e.g. emergency and/or high-priority call drops). 
     Consequently, for a special event (e.g. an emergency event, an event for new year&#39;s countdown, etc.) that may cause a huge amount of data transmission in a wireless communication network, a mechanism for managing data transmissions to prevent network from overloading is still in an urgent need. 
     SUMMARY 
     To solve the aforementioned problems, the present invention provides a base station, a wireless end device, and transmission barring methods thereof. 
     The base station of certain embodiments of the present invention comprises a first transceiving interface, a processor, and a second transceiving interface, wherein the processor is electrically connected to the first and second transceiving interfaces. The first transceiving interface is configured to receive a special event notification message from a core network. The processor is configured to generate a barring message after the first transceiving interface receives the special event notification message. The second transceiving interface is configured to transmit the barring message to at least one wireless end device to suspend the wireless end device from transmitting data to the base station for a barring time interval. The base station is not overloaded when the barring message is generated and transmitted. 
     The wireless end device of certain embodiments of the present invention comprises a transceiving interface and a processor, wherein the transceiving interface is electrically connected to the processor. The transceiving interface is configured to receive a barring message from a base station. The processor is configured to suspend the transceiving interface from transmitting data to the base station for a barring time interval. The base station is not overloaded when the barring message is received by the wireless end device. 
     The transmission barring method of certain embodiments of the present invention is for use in a base station. The base station comprises a first transceiving interface, a second transceiving interface, and a processor. The transmission barring method comprises the following steps of: receiving a special event notification message from a core network by the first transceiving interface, generating a barring message by the processor after receiving the special event notification message, and transmitting the barring message to at least one wireless end device by the second transceiving interface to suspend the wireless end device from transmitting data to the base station for a barring time interval. The base station is not overloaded when the barring message is generated and transmitted. 
     The transmission barring method of certain embodiments of the present invention is for use in a wireless end device. The wireless end device comprises a transceiving interface and a processor. The transmission barring method comprises the following steps of: receiving a barring message from a base station by the transceiving interface and suspending the transceiving interface from transmitting data to the base station for a barring time interval by the processor. The base station is not overloaded when the barring message is received by the wireless end device. 
     In certain embodiments of the present invention, a special event notification message is generated by the core network when a special event (e.g. emergency event, an event for new year&#39;s countdown, etc.) that may cause a huge amount of data transmission happens or is going to happen. After the base station receives the special event notification message from the core network, the base station will generate a barring message and transmits the barring message to some wireless end devices (e.g. lower priority user equipments and/or delay tolerant devices) in order to bar their data transmissions. It is emphasized that the base station is not overloaded when the barring message is generated and transmitted. By the mechanisms provided by the present invention, the number of data flows toward a base station can be greatly reduced when the special event happens. As a result, the problems of overload, call drops, and intolerable transmission delays can be mitigated. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates a schematic view of a conventional wireless communication network; 
         FIG. 2A  illustrates a schematic view of a wireless communication network  2  of the first embodiment of the present invention; 
         FIG. 2B  illustrates a block diagram of the base station  231  and a block diagram of the wireless end device  253 ; 
         FIG. 3  illustrates the data flows of the second embodiment of the present invention; 
         FIG. 4  illustrates the data flows of the third embodiment of the present invention; 
         FIG. 5  illustrates the data flows of the fourth embodiment of the present invention; 
         FIG. 6  illustrates the data flows of the fifth embodiment of the present invention; 
         FIG. 7  illustrates the data flows of the sixth embodiment of the present invention; 
         FIG. 8  illustrates the flowchart of the seventh embodiment of the present invention; 
         FIG. 9  illustrates the flowchart of the eighth embodiment of the present invention; 
         FIG. 10  illustrates the flowchart of the ninth embodiment of the present invention; 
         FIG. 11  illustrates the flowchart of the tenth embodiment of the present invention; 
         FIG. 12  illustrates the flowchart of the eleventh embodiment of the present invention; and 
         FIG. 13  illustrates the flowchart of the twelfth embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     In the following description, the present invention will be explained with reference to example embodiments thereof. However, these example embodiments are not intended to limit the present invention to any specific examples, embodiments, environment, applications, or particular implementations described in these embodiments. Therefore, description of these embodiments is only for purpose of illustration rather than to limit the present invention. It should be appreciated that, in the following embodiments and the attached drawings, elements unrelated to the present invention are omitted from depiction. 
     A first embodiment of the present invention is a wireless communication network  2 , which is illustrated in  FIG. 2A . The wireless communication network  2  may conform to the LTE standard, WiMAX standard, or other wireless communication standard that is well-known to people ordinary skilled in the art. The wireless communication network  2  comprises a core network  21 , two base stations  231 ,  233 , and a plurality of wireless end devices  251 ,  253 ,  271 ,  273 . It should be noted that the present invention does not limit the number of the base stations and the number of the wireless end devices in a wireless communication network. 
     The core network  21  may comprise a plurality of entities for providing communication services. For example, the core network  21  may comprise a mobility management entity, a serving gateway, and a packet data network gateway when the wireless communication network  2  conforms to the LTE standard. It should be noted that the present invention does not limit the number and the types of the entities comprised in the core network. 
     The base stations  231 ,  233  are electrically connected to the core network  21 . The wireless end devices  251 ,  253  are in the coverage  22  of the base station  231 , while the wireless end devices  271 ,  273  are in the coverage  24  of the base station  233 . Among the wireless end devices  251 ,  253 ,  271 ,  273 , the wireless end devices  251 ,  271  have higher priority for transmissions; that is, the wireless end devices  251 ,  271  may be delay intolerant devices (e.g. user equipments) whose phone calls and/or data transmissions are preferred not to be delayed. On the contrary, the wireless end devices  253 ,  273  have lower priority for transmissions and whose phone calls and/or data transmissions being delayed causes no harm. For example, the wireless end devices  253 ,  273  may be delay tolerant devices (e.g. smart meters) that simply periodically transmit collected data to the core network  21  via the base stations  231 ,  233  or may be user equipments that have lower priorities for transmission. 
     From the viewpoint of the present invention, the functionalities and operations of the base stations  231 ,  233  are the same, the functionalities and operations of the wireless end devices  251 ,  271  are the same, and the functionalities and operations of the wireless end devices  253 ,  273  are the same, so the following descriptions will focus on the base station  231 , one of the wireless end devices  251 , one of the wireless end devices  253 , and the core network  21 . 
       FIG. 2B  illustrates a block diagram of the base station  231  and a block diagram of the wireless end device  253 . The base station  231  comprises two transceiving interfaces  231   a ,  231   c  and a processor  231   b,  wherein the processor  231   b  is electrically connected to the transceiving interfaces  231   a,    231   c.  The wireless end device  253  comprises a transceiving interface  253   a  and a processor  253   b,  wherein the transceiving interface  253   a  is electrically connected to the processor  253   b.  Each of the transceiving interfaces  231   a,    231   c,    253   a  may be any one of various transceiving interfaces that are well known to those of ordinary skill in the art. Each of the processors  231   b,    253   b  may be any one of various processors, central processing units, microprocessors, or other calculating apparatuses that are well known to those of ordinary skill in the art. 
     When a special event (i.e. an event that may cause a huge amount of data transmission such as an emergency event, an event for new year&#39;s countdown, etc.) happens or is going to happen in a short time, a special event notification message  210  is generated by the core network  21  and then received by the transceiving interface  231   a  of the base station  231 . It is noted that when the special event is an emergency event, the special event notification message  210  is an emergency event notification message. 
     After receiving the special event notification message  210 , the base station  231  treats the wireless end devices  251 ,  253  differently. The wireless end device  253  has lower priority for transmissions, so whose data transmissions will be suspended by the base station  231 . On the contrary, the wireless end device  251  has higher priority for transmissions, so whose data transmissions (especially data transmission related to the emergency event) will not be suspended by the base station  231 . 
     To be more specific, after the base station  231  receives the special event notification message  210  for a short time period (e.g. immediately after receiving the special event notification message  210 ), the processor  231   b  generates a barring message  230  and an emergency alert indicator  232 . The transceiving interface  231   c  then transmits the barring message  230  and the emergency alert indicator  232  to the wireless end device  253  and the wireless end device  251  respectively. It is noted that the base station  231  is not overloaded when the barring message  230  is generated and transmitted. 
     The barring message  230  is used to suspend the wireless end device  253  from transmitting data to the base station  231  for a barring time interval (not shown). The barring time interval may be a predetermined one or recorded in the barring message  230 . From the viewpoint of the wireless end device  253 , the transceiving interface  253   a  receives the barring message  230  from the base station  231 . Similarly, it is noted that the base station  231  is not overloaded when the barring message  230  is received by the wireless end device  253 . After receiving the barring message  230 , the processor  253   b  suspends the transceiving interface  253   a  from transmitting data to the base station  231  for the barring time interval. 
     As to the emergency alert indicator  232 , it is used to enable the wireless end device  251  into an active mode so that the wireless end device  251  can receive emergency related information  234  from the base station  231 . Thereafter, the wireless end device  251  can request the base station  231  for making an emergency call and/or transmit data (especially data transmission related to the emergency event) to the base station  231 . 
     If the special event is still happening after a short period of time, the base station  231  may transmit another barring message  236  to the wireless end device  253 . After the transceiving interface  253   a  receives the barring message  236 , the processor  253   b  updates the barring time interval and continues to suspend the transceiving interface  253   a  for the updated bar time interval. On the contrary, if the special event ends, the transceiving interface  253   a  can perform data transmission again due to the bar time interval has expired. 
     For other more complicated embodiments, priorities for transmission may be defined into more than two levels. Each of the wireless end devices  251 ,  253  is assigned to one of the levels of the priorities. The base station  231  has to inform the wireless end devices  251 ,  253  of the level(s) of the priority to be barred by sending a barring identity(s). The barring identity(s) may be recorded in the barring message  230  or in another barring message. When the transceiving interface  253   a  of the wireless end device  253  receives the barring identity, the processor  253   b  checks whether the barring identity is the same as the level that the wireless end device  253  is assigned to. When the barring identity is the same as the priority that the wireless end device  253  is assigned to, the processor  253   b  then suspends the transceiving interface  253   a  from transmitting data to the base station  231  for the barring time interval. 
     According to the above descriptions, the wireless end devices  251 ,  253  have different priorities for transmissions when a special event happens. For the wireless end devices  251  (i.e. the ones that have higher priority for transmission), their data transmissions and phone calls will not be suspend during the special event. On the contrary, for the wireless end devices  253  (i.e. the ones that have lower priority for transmission), data transmissions and phone calls will be suspended for the barring time interval. Since the wireless end devices  253  within the coverage  22  of the base station  231  have been suspended from data transmission before the huge amount of data transmission in the wireless communication network  2  really occurs, the number of data flows toward the base station  231  can be reduced. As a result, the problems of overload, call drops, and intolerable transmission delays can be mitigated. 
     Please refer to  FIG. 2A ,  FIG. 2B , and  FIG. 3  for a second embodiment of the present invention. Similar to the first embodiment, the special event notification message  210  is generated by the core network  21  and then received by the transceiving interface  231   a  of the base station  231  when a special event happens or is going to happen in a short time. 
     In this embodiment, the processor  231   b  of the base station  231  generates a barring indicator  302  and the emergency alert indicator  232  after the transceiving interface  231   a  receives the special event notification message  210 . Then, the transceiving interface  231   c  transmits the barring indicator  302  to the wireless end device  253  within a paging cycle  34  of the wireless end device  253  and transmits the emergency alert indicator  232  to the wireless end device  251  within a paging cycle  32  of the wireless end device  251 . It is noted that the base station  231  is not overloaded when the barring indicator  302  is generated and transmitted. 
     It should be noted that, in some embodiments, the barring indicator  302  may be recorded in a paging message for the wireless end device  253  and the emergency alert indicator  232  may be recorded in a paging message for the wireless end device  251 . Yet in some other embodiments, the barring indicator  302  and the emergency alert indicator  232  may be recorded in the same paging message. For the embodiments that the barring indicator  302  and the emergency alert indicator  232  are recorded in a paging message (or paging messages), each of the barring indicator  302  and the emergency alert indicator  232  may be of one bit. 
     After receiving the emergency alert indicator  232  in its paging cycle  32 , the wireless end device  251  becomes active and receives emergency related information  234  recorded in a system information message from the base station  231 . Thereafter, the wireless end device  251  can request the base station  231  for making an emergency call and/or transmit data to the base station  231 , which is illustrated by the dashed arrows in  FIG. 3 . 
     As to the wireless end device  253 , the transceiving interface  253   a  receives the barring indicator  302  in its paging cycle  34 . It is noted that the base station  231  is not overloaded when the barring indicator  302  is received by the wireless end device  253 . Particularly, when the barring indicator  302  is recorded in a paging message for the wireless end device  253 , the transceiving interface  253   a  receives the barring indicator  302  by receiving the paging message. Then, the transceiving interface  253   a  receives the barring message  230  recorded in a system information message from the base station  231 . It is noted that the base station  231  is not overloaded when the barring message  230  is generated, transmitted, and received. In addition, the base station  231  transmits the barring message  230  by broadcasting or multicasting. In this embodiment, the barring message  230  records the barring time interval and the processor  253   b  suspends the transceiving interface  253   a  from transmitting data to the base station  231  for the barring time interval learned from the barring message  230 . 
     If the special event continues after a short period of time, the base station  231  transmits another barring message  236  to the wireless end device  253 . After the transceiving interface  253   a  receives the barring message  236 , the processor  253   b  updates the barring time interval according to the barring time interval recorded in the barring message  236  and continues to suspend the transceiving interface  253   a  for the updated barring time interval. It is noted that the base station  231  may transmit an additional barring indicator  304  prior to transmitting the barring message  236 , which is used to enable other wireless end device(s)  253  from the idle mode into the active mode. 
     Briefly speaking, the base station  231  simply uses the barring indicator  302  to inform the wireless end device  253  of the activation of the barring mechanism. Upon receiving the barring indicator  302 , the wireless end device  253  learns that it has to receive another barring message (i.e. the barring message  230 ) for the detailed barring information (e.g. barring time interval, barring identity, etc.). Afterwards, the wireless end device  253  is suspended for transmitting data to the base station  231 . 
     In addition to the aforesaid operations, the second embodiment can execute all the operations set forth for the first embodiment. How the second embodiment executes these operations will be readily appreciated by those of ordinary skill in the art based on the explanation of the first embodiment and thus will not be further described therein. 
     Please refer to  FIG. 2A ,  FIG. 2B , and  FIG. 4  for a third embodiment of the present invention. Similar to the first embodiment, the special event notification message  210  is generated by the core network  21  and then received by the transceiving interface  231   a  of the base station  231  when a special event happens or is going to happen in a short time. 
     After the transceiving interface  231   a  receives the special event notification message  210 , the processor  231   b  generates the barring message  230  and the emergency alert indicator  232 . Then, the transceiving interface  231   c  transmits the barring message  230  to the wireless end device  253  within the paging cycle  34  of the wireless end device  253  and transmits the emergency alert indicator  232  to the wireless end device  251  within the paging cycle  32  of the wireless end device  251 . The base station  231  is not overloaded when the barring message  230  is generated and transmitted. It should be noted that, in some embodiments, the barring message  230  may be recorded in a paging message for the wireless end device  253  and the emergency alert indicator  232  may be recorded in a paging message for the wireless end device  251 . Yet in some other embodiments, the barring message  230  and the emergency alert indicator  232  may be recorded in the same paging message. For those embodiments, each of the barring message  230  and the emergency alert indicator  232  may be of one bit. 
     After receiving the emergency alert indicator  232  in its paging cycle  32 , the wireless end device  251  becomes active and receives emergency related information  234  in system information message from the base station  231 . Thereafter, the wireless end device  251  can request the base station  231  for making an emergency call and/or transmit data to the base station  231 , which is illustrated by the dashed arrows in  FIG. 4 . 
     As to the wireless end device  253 , the transceiving interface  253   a  receives the barring message  230  in its paging cycle  34 . Particularly, when the barring message  230  is recorded in a paging message for the wireless end device  253 , the transceiving interface  253   a  receives the barring message  230  by receiving the paging message. The base station  231  is not overloaded when the barring message  230  is received by the wireless end device  253 . Then, the processor  253   b  suspends the transceiving interface  253   a  from transmitting data to the base station  231  for a barring time interval. It is noted that the barring time interval is a predetermined one. 
     If the special event continues after a short period of time, the base station  231  transmits another barring message  236  within another paging cycle  36  of the wireless end device  253 . After the transceiving interface  253   a  receives the barring message  236  in the paging cycle  36 , the processor  253   b  suspends the transceiving interface  253   a  from transmitting data to the base station  231  for the predetermined barring time interval again. 
     Briefly speaking, the base station  231  simply uses the barring message  230  to inform the wireless end device  253  of the barring information. Upon receiving the barring message  230 , the wireless end device  253  learns that it has to be suspended for transmitting data to the base station  231  for the predetermined barring time interval. 
     In addition to the aforesaid operations, the third embodiment can execute all the operations set forth for the first embodiment. How the third embodiment executes these operations will be readily appreciated by those of ordinary skill in the art based on the explanation of the first embodiment and thus will not be further described therein. 
     Please refer to  FIG. 2A ,  FIG. 2B , and  FIG. 5  for a fourth embodiment of the present invention. Similar to the first to third embodiments, the special event notification message  210  is generated by the core network  21  and then received by the transceiving interface  231   a  of the base station  231  when a special event happens or is going to happen in a short time. 
     After the transceiving interface  231   a  receives the special event notification message  210 , the processor  231   b  generates the emergency alert indicator  232 . Then, the transceiving interface  231   c  transmits the emergency alert indicator  232  to the wireless end device  251  within the paging cycle  32  of the wireless end device  251 . It should be noted that, in some embodiments, the emergency alert indicator  232  may be recorded in a paging message for the wireless end device  251  and may be of one bit. 
     After receiving the emergency alert indicator  232  in its paging cycle  32 , the wireless end device  251  becomes active and receives emergency related information  234  recorded in a system information message from the base station  231 . Thereafter, the wireless end device  251  can request the base station  231  for making an emergency call and/or transmit data to the base station  231 , which is illustrated by the dashed arrows in  FIG. 5 . 
     As to the wireless end device  253 , its paging cycle  34  and the paging cycle  32  of the wireless end device  251  overlap, so the transceiving interface  253   a  can listen for emergency alert indicator within the paging cycle  34 . After the transceiving interface  253   a  listens to the emergency alert indicator  232  within the paging cycle  34 , the processor  253   b  enables the transceiving interface  253   a  into an active mode. Then, the transceiving interface  253   a  receives the barring message  230  recorded in a system information message from the base station  231 . The barring message  230  is transmitted from the base station  231  by broadcasting or multicasting. The barring message  230  records the barring time interval and the processor  253   b  then suspends the transceiving interface  253   a  from transmitting data to the base station  231  for the barring time interval learned from the barring message  230 . It is noted that the base station  231  is not overloaded when the barring message  230  is generated, transmitted, and received. 
     It should be emphasized that the present invention does not limit the transmission sequence of the emergency related information  234  and the barring message  230 . That is, after transmitting the emergency alert indicator  232 , the base station  231  may transmit the emergency related information  234  and the barring message  230  in any sequence. 
     If the special event continues after a short period of time, the base station  231  transmits another barring message  236  to the wireless end device  253 . After the transceiving interface  253   a  receives the barring message  236 , the processor  253   b  updates the barring time interval according to the barring time interval recorded in the barring message  236  and continues to suspend the transceiving interface  253   a  for the updated barring time interval. It is noted that, prior to transmitting the barring message  236 , the base station  231  may transmit an additional emergency alert indicator  502  within another paging cycle  38  and another emergency related information  504  to other wireless end device(s)  251 . 
     Likewise, it should be emphasized that the present invention does not limit the transmission sequence of the emergency related information  504  and the barring message  236 . That is, after transmitting the emergency alert indicator  502 , the base station  231  may transmit the emergency related information  504  and the barring message  236  in any sequence. 
     Briefly speaking, the wireless end device  253  listens for an emergency alert indicator  232  that is transmitted to the wireless end device  251 . Upon listening to the emergency alert indicator  232 , the wireless end device  253  learns that it has to receive a barring message (i.e. the barring message  230 ) for the detailed barring information (e.g. barring time interval, barring identity, etc.). Afterwards, the wireless end device  253  is suspended for transmitting data to the base station  231 . 
     In addition to the aforesaid operations, the fourth embodiment can execute all the operations set forth for the first embodiment. How the fourth embodiment executes these operations will be readily appreciated by those of ordinary skill in the art based on the explanation of the first embodiment and thus will not be further described therein. 
     Please refer to  FIG. 2A ,  FIG. 2B , and  FIG. 6  for a fifth embodiment of the present invention. Similar to the first to fourth embodiments, the special event notification message  210  is generated by the core network  21  and then received by the transceiving interface  231   a  of the base station  231  when a special event happens or is going to happen in a short time. 
     In this embodiment, the processor  231   b  of the base station  231  generates a scheduling message  602  of a plurality of system information blocks after the transceiving interface  231   a  receives the special event notification message  210 . Then, the transceiving interface  231   c  broadcasts the scheduling message  602  during a system information transmission interval. From the viewpoint of the wireless end device  253 , its transceiving interface  253   a  receives the scheduling message  602  and learns the arrangement of the system information blocks. Next, the transceiving interface  253   a  receives the barring message  230  recorded in at least one of the system information blocks according to the arrangement indicated by the scheduling message  602 . The barring message  230  records the barring time interval and the processor  253   b  suspends the transceiving interface  253   a  from transmitting data to the base station  231  for the barring time interval learned from the barring message  230 . It should be noted that the barring message  230  may be recorded in the scheduling message  602  in some other embodiments. In addition, it is emphasized that the base station  231  is not overloaded when the barring message  230  is generated, transmitted, and received. 
     In this embodiment, the processor  231   b  also generates an emergency alert indicator  232  after the transceiving interface  231   a  receives the special event notification message  210 . Then, the transceiving interface  231   c  transmits the emergency alert indicator  232  to the wireless end device  251  within the paging cycle  32  of the wireless end device  251 . It should be noted that, in some embodiments, the emergency alert indicator  232  may be recorded in a paging message for the wireless end device  251 . For those embodiments, the emergency alert indicator  232  may be of one bit. 
     After receiving the emergency alert indicator  232  in its paging cycle  32 , the wireless end device  251  becomes active and receives emergency related information  234  recorded in a system information message from the base station  231 , wherein the system information message may be one of the aforementioned system information blocks. Thereafter, the wireless end device  251  can request the base station  231  for making an emergency call and/or transmit data to the base station  231 , which is illustrated by the dashed arrows in  FIG. 6 . 
     It should be emphasized that the present invention does not limit the transmission sequence of the emergency related information  234  and the barring message  230 ; that is, the time instant for transmitting the emergency related information  234  may be prior to, later to, or at the same as the time instant for transmitting the barring message  230 . 
     If the special event continues after a short period of time, the base station  231  transmits another scheduling message  604  of other system information blocks and another barring message  236  to the wireless end device  253 . After the transceiving interface  253   a  receives the barring message  236 , the processor  253   b  updates the barring time interval according to the barring time interval recorded in the barring message  236  and continues to suspend the transceiving interface  253   a  for the updated barring time interval. 
     Briefly speaking, the base station  231  broadcasts the scheduling message  602  of the system information blocks. The wireless end device  253  learns that it has to receive the barring message  230  for the detailed barring information (e.g. barring time interval, barring identity, etc.) according to the scheduling message  602 . Afterwards, the wireless end device  253  is suspended for transmitting data to the base station  231 . 
     In addition to the aforesaid operations, the fifth embodiment can execute all the operations set forth for the first embodiment. How the fifth embodiment executes these operations will be readily appreciated by those of ordinary skill in the art based on the explanation of the first embodiment and thus will not be further described therein. 
     Please refer to  FIG. 2A ,  FIG. 2B , and  FIG. 7  for a sixth embodiment of the present invention. Similar to the first to fifth embodiments, the special event notification message  210  is generated by the core network  21  and then received by the transceiving interface  231   a  of the base station  231  when a special event happens or is going to happen in a short time. 
     After the transceiving interface  231   a  receives the special event notification message  210 , the processor  231   b  generates the emergency alert indicator  232 . Then, the transceiving interface  231   c  transmits the emergency alert indicator  232  to the wireless end device  251  within the paging cycle  32  of the wireless end device  251 . It should be noted that, in some embodiments, the emergency alert indicator  232  may be recorded in a paging message for the wireless end device  251 . For those embodiments, the emergency alert indicator  232  may be of one bit. 
     After receiving the emergency alert indicator  232  in its paging cycle  32 , the wireless end device  251  becomes active and receives emergency related information  234  recorded in a system information message from the base station  231 . Thereafter, the wireless end device  251  can request the base station  231  for making an emergency call and/or transmit data to the base station  231 , which is illustrated by the dashed arrows in  FIG. 7 . 
     The processor  231   b  of the base station  231  also generates the barring message  230  and the transceiving interface  231   c  then transmits the barring message  230  to the wireless end device  253  by broadcasting. The base station  231  is not overloaded when the barring message  230  is generated and transmitted. In some other embodiments, the barring message  230  may be recorded in a master information block or a system information block. When the barring message  230  is recorded in master information block, it may be of one bit. 
     From the viewpoint of the wireless end device  253 , its transceiving interface  253   a  receives the barring message  230 . It is noted that the base station  231  is not overloaded when the barring message  230  is received by the wireless end device  253 . Then, the processor  253   b  suspends the transceiving interface  253   a  from transmitting data to the base station  231  for a barring time interval. It is noted that the barring time interval is a predetermined one. 
     If the special event continues after a short period of time, the base station  231  transmits another barring message  236  to the wireless end device  253  by broadcasting again. Likewise, the barring message  230  may be recorded in a master information block or a system information block. After the transceiving interface  253   a  receives the barring message  236 , the processor  253   b  suspends the transceiving interface  253   a  from transmitting data to the base station  231  for the predetermined barring time interval again. 
     Briefly speaking, the base station  231  broadcasts the barring message  230  in a master information block or a system information block. Upon receiving the barring message  230 , the wireless end device  253  learns that it has to be suspended for transmitting data to the base station  231  for the predetermined barring time interval. In addition to the aforesaid operations, the sixth embodiment can execute all the operations set forth for the first embodiment. How the sixth embodiment executes these operations will be readily appreciated by those of ordinary skill in the art based on the explanation of the first embodiment and thus will not be further described therein. 
     A seventh embodiment of the present invention is a transmission barring method, whose flowchart is illustrated in  FIG. 8 . The transmission barring method can be used for a wireless communication network comprising a core network, a base station, and a wireless end device. The wireless end device has a lower priority for transmission in the wireless communication network. For example, the wireless end device may be a delay tolerant device. The base station comprises a first transceiving interface, a processor, and a second transceiving interface, while the wireless end device comprises a processor and a transceiving interface. 
     When a special event happens or is going to happen in a short time, the core network transmits a special event notification message. Afterwards, step  801  is executed by the first transceiving interface of the base station for receiving the special event notification message from the core network. Then, step  803  is executed by the processor of the base station for generating a barring message. Next, step  805  is executed by the second transceiving interface of the base station for transmitting the barring message to the wireless end device. 
     From the viewpoint of the wireless end device, step  807  is executed by the transceiving interface of the wireless end device for receiving the barring message. Next, step  809  is executed by the processor of the wireless end device for suspending the transceiving interface of the wireless end device from transmitting data to the base station for a barring time interval. It is noted that the barring time interval may be a predetermined one or may be recorded in the barring message. It is noted that the base station is not overloaded when the aforesaid steps  803 ,  805 , and  807  are executed. 
     In case that the special event continues, the transmission barring method repeats the aforementioned steps  803 ,  805 ,  807 , and  809  and the wireless end device will updates the barring time interval accordingly. 
     It is noted that, in some embodiments, the barring message generated in step  803  may record an identity indicating which wireless end device to be suspended. In this way, the wireless end device has to execute another step after the step  807  to determine whether the identity recoded in the barring message is the same as the identity of the wireless end device. The wireless end device will execute step  809  only when the two identities are the same. 
     In addition to the aforesaid steps, the seventh embodiment can execute all the operations set forth for the first embodiment. How the seventh embodiment executes these operations will be readily appreciated by those of ordinary skill in the art based on the explanation of the first embodiment and thus will not be further described therein. 
     An eighth embodiment of the present invention is a transmission barring method, whose flowchart is illustrated in  FIG. 9 . The transmission barring method can be used for a wireless communication network comprising a core network, a base station, and a wireless end device. The wireless end device has a lower priority for transmission in the wireless communication network. For example, the wireless end device may be a delay tolerant device. The base station comprises a first transceiving interface, a processor, and a second transceiving interface, while the wireless end device comprises a processor and a transceiving interface. 
     When a special event happens or is going to happen in a short time, the core network transmits a special event notification message. Afterwards, step  901  is executed by the first transceiving interface of the base station for receiving the special event notification message from the core network. Next, step  903  is executed by the processor of the base station for generating a barring indicator. Following that, step  905  is executed by the second transceiving interface of the base station for transmitting the barring indicator to the wireless end device within a paging cycle of the wireless end device. Next, step  907  is executed by the transceiving interface of the wireless end device to receive the barring indicator within its paging cycle. 
     It is noted that, in some embodiment, the barring indicator may be recorded in a paging message. Hence, step  905  transmits the barring indicator by transmitting the paging message, while step  907  receives the barring indicator by receiving the paging message. 
     Following that, step  909  is executed by the processor of the base station for generating a barring message. It is noted that the barring message generated in step  909  comprises additional barring information, such as the barring time interval, barring identity, etc. Step  911  is then executed by the second transceiving interface of the base station for transmitting the barring message to the wireless end device. Next, step  913  is executed by the transceiving interface of the wireless end device for receiving the barring message. Afterwards, the wireless end device derives the barring time interval and its processor executes step  915  for suspending its transceiving interface from transmitting data to the base station for the barring time interval. It is noted that the base station is not overloaded when the steps  903 ,  905 ,  907 ,  909 ,  911 , and  913  are executed. 
     In case that the special event continues, the transmission barring method repeats the aforementioned steps  909 ,  911 ,  913 , and  915  and the wireless end device will updates the barring time interval accordingly. 
     In addition to the aforesaid steps, the eighth embodiment can execute all the operations set forth for the second embodiment. How the eighth embodiment executes these operations will be readily appreciated by those of ordinary skill in the art based on the explanation of the second embodiment and thus will not be further described therein. 
     A ninth embodiment of the present invention is a transmission barring method, whose flowchart is illustrated in  FIG. 10 . The transmission barring method can be used for a wireless communication network comprising a core network, a base station, and a wireless end device. The wireless end device has a lower priority for transmission in the wireless communication network. For example, the wireless end device may be a delay tolerant device. The base station comprises a first transceiving interface, a processor, and a second transceiving interface, while the wireless end device comprises a processor and a transceiving interface. 
     When a special event happens or is going to happen, the core network transmits a special event notification message. Afterwards, step  1001  is executed by the first transceiving interface of the base station for receiving the special event notification message from the core network. Then, step  1003  is executed by the processor of the base station for generating a barring message. Next, step  1005  is executed by the second transceiving interface of the base station for transmitting the barring message to the wireless end device within a paging cycle of the wireless end device. 
     From the viewpoint of the wireless end device, step  1007  is executed by the transceiving interface of the wireless end device for receiving the barring message within its paging cycle. It is noted that the base station is not overloaded when the steps  1003 ,  1005 , and  1007  are executed. Next, step  1009  is executed by the processor of the wireless end device for suspending the transceiving interface of the wireless end device from transmitting data to the base station for a barring time interval. It is noted that the barring time interval may be a predetermined one or may be recorded in the barring message. 
     In case that the special event continues, the transmission barring method repeats the aforementioned steps  1003 ,  1005 ,  1007 , and  1009  and the wireless end device will updates the barring time interval accordingly. 
     In addition to the aforesaid steps, the ninth embodiment can execute all the operations set forth for the third embodiment. How the ninth embodiment executes these operations will be readily appreciated by those of ordinary skill in the art based on the explanation of the third embodiment and thus will not be further described therein. 
     A tenth embodiment of the present invention is a transmission barring method, whose flowchart is illustrated in  FIG. 11 . The transmission barring method can be used for a wireless communication network comprising a core network, a base station, a first wireless end device, and a second wireless end device. The second wireless end device has a higher priority for transmission, while the first wireless end device has a lower priority for transmission. The base station comprises a first transceiving interface, a processor, and a second transceiving interface, while the first wireless end device comprises a processor and a transceiving interface. 
     When a special event happens or is going to happen, the core network transmits a special event notification message. Afterwards, step  1101  is executed by the first transceiving interface of the base station for receiving the special event notification message from the core network. Next, step  1103  is executed by the processor of the base station for generating an emergency alert indicator. Following that, step  1105  is executed by the second transceiving interface of the base station for transmitting the emergency alert indicator to the second wireless end device within a paging cycle of the second wireless end device. 
     Next, step  1107  is executed by the transceiving interface of the first wireless end device for listening to the emergency alert indicator within a paging cycle of the first wireless end device. This is feasible because the paging cycle of the first wireless end device overlaps that of the second wireless end device. By listening to the emergency alert indicator, the first wireless end device learns that it has to receive a barring message later. 
     Following that, step  1109  is executed by the processor of the base station for generating the barring message, which may comprise additional barring information, such as the barring time interval. Step  1111  is then executed by the second transceiving interface of the base station for transmitting the barring message to the first wireless end device. Next, step  1113  is executed by the transceiving interface of the first wireless end device for receiving the barring message. It is emphasized that the base station is not overloaded when the steps  1109 ,  1111 , and  1113  are executed. Afterwards, the first wireless end device derives the barring time interval and its processor executes step  1113  for suspending its transceiving interface from transmitting data to the base station for the barring time interval. 
     In case that the special event continues, the transmission barring method repeats the aforementioned steps  1109 ,  1111 ,  1113 , and  1115  and the first wireless end device will updates the barring time interval accordingly. 
     In addition to the aforesaid steps, the tenth embodiment can execute all the operations set forth for the fourth embodiment. How the tenth embodiment executes these operations will be readily appreciated by those of ordinary skill in the art based on the explanation of the fourth embodiment and thus will not be further described therein. 
     An eleventh embodiment of the present invention is a transmission barring method, whose flowchart is illustrated in  FIG. 12 . The transmission barring method can be used for a wireless communication network comprising a core network, a base station, and a wireless end device. The wireless end device has a lower priority for transmission in the wireless communication network. For example, the wireless end device may be a delay tolerant device. The base station comprises a first transceiving interface, a processor, and a second transceiving interface, while the wireless end device comprises a processor and a transceiving interface. 
     When a special event happens or is going to happen in a short time, the core network transmits a special event notification message. Afterwards, step  1201  is executed by the first transceiving interface of the base station for receiving the special event notification message from the core network. Next, step  1203  is executed by the processor of the base station for generating a scheduling message of a plurality of system information blocks. Following that, step  1205  is executed by the second transceiving interface of the base station for broadcasting the scheduling message. Next, step  1207  is executed by the transceiving interface of the wireless end device to receive the scheduling message. From the scheduling message, the wireless end device learns the time to receive a barring message. 
     Following that, step  1209  is executed by the processor of the base station for generating a barring message, which comprises additional barring information, such as the barring time interval. Step  1211  is then executed by the second transceiving interface of the base station for transmitting the barring message to the wireless end device. Next, step  1213  is executed by the transceiving interface of the wireless end device for receiving the barring message. It is noted that the base station is not overloaded when the steps  1209 ,  1211 , and  1213  are executed. Afterwards, the wireless end device derives the barring time interval and its processor executes step  1215  for suspending its transceiving interface from transmitting data to the base station for the barring time interval. 
     In case that the special event continues, the transmission barring method repeats the aforementioned step  1205  to step  1215  and the wireless end device will updates the barring time interval accordingly. 
     In addition to the aforesaid steps, the eleventh embodiment can execute all the operations set forth for the fifth embodiment. How the eleventh embodiment executes these operations will be readily appreciated by those of ordinary skill in the art based on the explanation of the fifth embodiment and thus will not be further described therein. 
     A twelfth embodiment of the present invention is a transmission barring method, whose flowchart is illustrated in  FIG. 13 . The transmission barring method can be used for a wireless communication network comprising a core network, a base station, and a wireless end device. The wireless end device has a lower priority for transmission in the wireless communication network. For example, the wireless end device may be a delay tolerant device. The base station comprises a first transceiving interface, a processor, and a second transceiving interface, while the wireless end device comprises a processor and a transceiving interface. 
     When a special event happens or is going to happen in a short time, the core network transmits a special event notification message. Afterwards, step  1301  is executed by the first transceiving interface of the base station for receiving the special event notification message from the core network. Then, step  1303  is executed by the processor of the base station for generating a barring message in one of a master information block and a system information block. Next, step  1305  is executed by the second transceiving interface of the base station for transmitting the barring message by broadcasting the master information block or the system information block (depending on which one comprises the barring message). 
     From the viewpoint of the wireless end device, step  1307  is executed by the transceiving interface of the wireless end device for receiving the barring message. It is noted that the base station is not overloaded when the steps  1303 ,  1305 , and  1307  are executed. Next, step  1309  is executed by the processor of the wireless end device for suspending the transceiving interface of the wireless end device from transmitting data to the base station for a barring time interval. It is noted that the barring time interval may be a predetermined one or may be recorded in the barring message. 
     In case that the special event continues, the transmission barring method repeats the aforementioned steps  1303 ,  1305 ,  1307 , and  1309  and the wireless end device will updates the barring time interval accordingly. 
     In addition to the aforesaid steps, the twelfth embodiment can execute all the operations set forth for the sixth embodiment. How the twelfth embodiment executes these operations will be readily appreciated by those of ordinary skill in the art based on the explanation of the sixth embodiment and thus will not be further described therein. 
     According to the above embodiments, wireless end devices of a wireless communication network have different priorities for transmissions when a special event happens or is going to happen in a short time. For wireless end devices that have higher priority for transmission, their data transmissions and phone calls will not be suspend during the special event. On the contrary, for the wireless end devices that have lower priority for transmission, their data transmissions and phone calls will be suspended for the barring time interval. By the mechanisms provided by the present invention, the number of data flows toward a base station can be greatly reduced when the special event happens. As a result, the problems of overload, call drops, and intolerable transmission delays can be mitigated. 
     The above disclosure is related to the detailed technical contents and inventive features thereof. People skilled in this field may proceed with a variety of modifications and replacements based on the disclosures and suggestions of the invention as described without departing from the characteristics thereof. Nevertheless, although such modifications and replacements are not fully disclosed in the above descriptions, they have substantially been covered in the following claims as appended.