Abstract:
A method and apparatus for service level recognition and registration processing in a wireless communication device are provided. According to one aspect of the present invention, a method is provided for transitioning between service modes and indicating a current service mode to a user of a wireless communication device. The status of a signal associated with a forward channel from a messaging system to the wireless communication device is determined. A quality metric is determined based upon the status over a predetermined period of time. Three service modes, including a full service mode, a basic service mode, and a storing service mode are provided. In the storing service mode, after determining the quality metric is better than a first predetermined threshold a transition is made to the basic service mode. In the basic service mode, after verification of a reverse channel from the wireless communication device to the messaging system a transition is made to the full service mode. In the full service mode if the reverse channel becomes degraded, then a transition is made to the basic service mode. The current service mode is indicated to the user. According to another aspect of the present invention, a wireless communication device performs registration processing based upon the current service mode of the wireless communication device. Three service modes are recognized, including: a storing service mode in which new messages destined for the wireless communication device are not received by the wireless communication device; a basic service mode in which new messages destined for the wireless communication device are received by the wireless communication device, and a full service mode in which both new messages and stored messages are received by the wireless communication device. A registration process determines what action to take based upon the current service mode.

Description:
This application is a continuation of prior application Ser. No. 09/089,271 filed Jun. 2, 1998, now U.S. Pat. No. 6,216,001 the priority of which is hereby claimed. 

   FIELD OF THE INVENTION 
   The invention relates generally to the field of wireless communications. More particularly, the invention relates to a method of recognizing a service area in which the wireless communication device is located and indicating the current service level to the user of a wireless communication device and a method of registering the wireless communication device with a messaging system. 
   BACKGROUND OF THE INVENTION 
   Communications systems generally transfer information between a source and a destination. An exemplary two-way communication system  100  is illustrated by  FIG. 1A . The communication system  100  includes a network  110  (e.g., a paging system or other messaging system) and a wireless communication device  120  (e.g., a pager or other mobile wireless communication device). The communication system  100  also includes a transmitter, such as base transmitter  111 , and a receiver, such as base receiver  112 , which transmit and receive information signals over some media, respectively. This media may be cable wiring or the atmosphere, for example. When communications occur over the atmosphere, or air waves, they are commonly referred to as “wireless” communications. Examples of wireless communications systems include digital cellular, packet data paging, digital cordless telephones, wireless modems, wireless local and wide area networks, digital satellite communications and personal communications networks. 
   Returning to  FIG. 1A , the base transmitter  111  is typically mounted to a tower that is 120 to 800 feet high and is significantly more powerful than the transmitter of the wireless communication device  120 , which is typically located approximately 3 feet from the ground. Consequently, the distance at which reliable message exchange can take place from the base transmitter  111  to the wireless communication device  120 , labeled R 1 , is much greater than the distance at which reliable message exchange can take place from the wireless communication device  120  to the base receiver  112 , labeled R 2 . Therefore, one of the many challenges faced by designers of communications systems and wireless communication devices is how to resolve the imbalance in bit-error rates between the forward channel (i.e., the path from the network  110  to the wireless communication device  120 ) and the reverse channel (i.e., the path from the wireless communication device  120  to the network  110 ). 
   One prior technique balancing the in-bound and out-bound bit-error rates in a two-way paging system is illustrated by  FIG. 1B . According to this technique, the problem is solved with an appropriate network design. In this example, the network topology is designed such that whenever a wireless communication device  120  is within range of a base transmitter  111 , it will also be within range of a base receiver  112 . However, it should be appreciated this solution is extremely costly. Further, since occasional lapses in coverage on the reverse channel are tolerable for pager users, the additional expense to make the forward and reverse channel coverage areas identical is not cost effective. 
   What is desirable, therefore, rather than additional receivers per transmitter, is a mechanism for distinguishing between the various coverage combinations and for effectively conveying the current service level (e.g., the current capabilities of the wireless communication device) to the user. Advantageously, in this manner, the user of the wireless communication device will have the appropriate expectation of his/her current ability to originate and/or receive messages by way of the wireless communication device. Additionally, it is desirable to use this same mechanism as a foundation for the wireless communication device&#39;s registration processing. 
   SUMMARY OF THE INVENTION 
   A method and apparatus for service level recognition and registration processing in a wireless communication device are described. According to one aspect of the present invention, the current service level of a wireless communication device is determined. Three distinct levels of service are provided including a first level of service, a second level of service, and a third level of service. The method distinguishes between the first service level and the second service level based upon one or more characteristics of a forward channel from a messaging system to the wireless communication device. The method further distinguishes between the second service level and the third service level based upon one or more characteristics of a reverse channel from the wireless communication device to the messaging system. 
   According to another aspect of the present invention, a method is provided for transitioning between service modes and indicating a current service mode to a user of a wireless communication device. The status of a signal associated with a forward channel from a messaging system to the wireless communication device is determined. A quality metric is determined based upon the status over a predetermined period of time. Three service modes, including a full service mode, a basic service mode, and a storing service mode are provided. In the storing service mode, after determining the quality metric is better than a first predetermined threshold a transition is made to the basic service mode. In the basic service mode, after verification of a reverse channel from the wireless communication device to the messaging system a transition is made to the full service mode. In the full service mode if the reverse channel becomes degraded, then a transition is made to the basic service mode. The current service mode is indicated to the user. 
   According to another aspect of the present invention, a wireless communication device performs registration processing based upon the current service mode of the wireless communication device. Three service modes are recognized, including: a storing service mode in which new messages destined for the wireless communication device are not received by the wireless communication device; a basic service mode in which new messages destined for the wireless communication device are received by the wireless communication device, and a full service mode in which both new messages and stored messages are received by the wireless communication device. A registration process determines what action to take based upon the current service mode. 
   Other features of the present invention will be apparent from the accompanying drawings and from the detailed description which follows. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention is illustrated by way of example, and not by way of imitation, in the figures of the accompanying drawings and in which like reference numerals refer to similar elements and in which: 
       FIG. 1A  illustrates an exemplary two-way communication system in which the present invention may be employed according to one embodiment of the present invention. 
       FIG. 1B  is a diagram depicting a relationship between the location of a base transmitter and base receivers. 
       FIG. 2  illustrates three service areas among which a wireless communication device may distinguish according to one embodiment of the present invention. 
       FIG. 3  illustrates an exemplary wireless communication device in which one embodiment of the present invention may be implemented. 
       FIG. 4  is a block diagram illustrating various functional units according to one embodiment of the present invention. 
       FIG. 5  is a state diagram illustrating three states in which a wireless communication device may be according to one embodiment of the present invention. 
       FIG. 6  is a more detailed diagram of the states of  FIG. 5  according to one embodiment of the present invention. 
       FIGS. 7A–7G  are a flow diagram illustrating a method of registration processing according to one embodiment of the present invention. 
   

   DETAILED DESCRIPTION 
   An improved method and apparatus for determining the current service level of a wireless communication device and for registering the wireless communication device with a messaging system is described. In the following description, for the purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the present invention. It will be apparent, however, to one skilled in the art that the present invention may be practiced without some of these specific details. In other instances, well-known structures and devices are shown in block diagram form. 
   The present invention includes various steps, which will be described below. The steps may be embodied in machine-executable instructions, which may be used to cause a general-purpose or special-purpose processor programmed with the instructions to perform the steps. Alternatively, the steps may be performed by a combination of hardware and software. Importantly, while embodiments of the present invention will be described with reference to a handheld two-way pager, the method and apparatus described herein are equally applicable to other types of wireless communication devices such as cellular phones, wireless networking devices and the like. 
   Service Areas 
   In two-way communications systems, such as two-way paging systems, it should be apparent that three distinct service or coverage areas exist. As one advantage of the present invention a mechanism is disclosed for determining in which service area the wireless communication device  120  is located by evaluating characteristics of both the forward and reverse channels. 
   The three service areas in which a two-way wireless communication device  120  may be located will now be discussed with reference to  FIG. 2 . In a first service area  200 , the wireless communication device  120  can receive transmissions from the base transmitter  111  and the base receiver  112  can receive transmissions originated by the wireless communication device  120 . This service area, therefore, represents an area in which both the base transmitter  111  and the base receiver  112  have good coverage. It is in this area that reliable two-way communications, such as two-way paging, may take place. When a wireless communication device  120  is in this service area  200  and has registered with the messaging service (as is generally required by messaging protocols involving mobile communication devices), it is said to be in “Full Service.” 
   In a second service area  210 , the wireless communication device  120  can receive transmissions from the base transmitter  111 , but the base receiver  112  cannot receive transmissions originated by the wireless communication device  120 . This service area, therefore, is only useful for one-way communications. When a wireless communication device  120  is in this service area  210 , it is said to be in “Basic Service.” 
   In a third service area  220 , the wireless communication device  120  is incapable of receiving transmissions from the base transmitter  111  and the base receiver  112  cannot receive transmissions originated by the wireless communication device  120 . As a result, neither one-way or two-way communications may take place in this service area  220 . According to one embodiment, when a wireless communication device  120  is in this service area  220 , it is said to be “Out of Range.” However, in alternative embodiments, the message service may store undelivered messages and deliver them at a later time (e.g., upon successful registration by the wireless communication device  120 ), in which case the service level of the wireless communication device  120  is referred to as “Storing Service.” Importantly, it should be appreciated that obstructions or other interference may cause discontinuities in the service areas. For example, one or more Storing Service or Out of Range areas may be located within the first and second service areas  200  and  210  as illustrated. The three service levels (Full, Basic, and Storing Service), and the novel mechanism for determining the appropriate state of the wireless communication device  120  is described further below. 
   At this point, it may be instructive to compare the three service areas ( 200 ,  210 , and  220 ) to cellular and one-way paging service areas. In a cellular communication system, because one-way voice communication is not useful, the network is designed such that R 1  and R 2  (of  FIG. 1   a ) are equal. That is, the network is comprised of many first service areas  200  bumped up against each other to provide symmetric in-bound and out-bound paths. As a result, only two service areas are available. In the first, the cell phone can receive transmissions from the transmitter and the receiver can receive communications from the cell phone. However, in the second, because R 1  and R 2  are equal, both the transmitter and receiver are out of range. Therefore, in a cellular system, the second service area  210  and the third service area  220  are equivalent (e.g., out of range). 
   One-way paging systems also have only two distinct service areas (e.g., in range and out of range). In a one-way paging system, there is no reverse channel from the wireless communication device  120  to the messaging service  110 . Therefore, for a one-way paging system, there is no equivalent to the first service area  200  of the two-way communication system. 
   In contrast to the simplistic service level determination (e.g., signal or no signal) required for cellular and one-way paging systems, the present invention provides the capability to distinguish among three distinct service areas. 
   An Exemplary Wireless Communication Device 
     FIG. 3  is a simplified block diagram of a handheld wireless communication device  120  in which the method of the present invention may be implemented. In the embodiment depicted, the device  120  may be a two-way electronic pager, a wireless modem, a cell telephone or any other device for receiving and transmitting RF transmissions. Device  120  includes a RF receiver  310 , a RF transmitter  371 , a processor  361 , a non-volatile code storage  363 , a memory  365 , and an I/O interface  367 , all intercoupled by a bus  362 . According to one embodiment of the present invention, the processor  361  executes program code stored in code storage  363  to perform the processing involved in determining the wireless communication device&#39;s current level of service and the registration processing described below and other functions of the device  120 . Memory  365  is used to store the results of intermediate calculations and other program variables. The I/O interface  367  will typically include an assortment of components coupled to bus  362  that varies based on the application of the device  120 . For example, if device  120  is an electronic pager, I/O interface  367  would typically include a number of buttons to receive user input, a display for displaying messages and other information and a notification mechanism such as a beeper or vibrator to alert the user that a message has been received. In the case of a cell telephone, I/O interface  367  would typically include a numeric keypad, certain control buttons, a microphone and a speaker. In other applications I/O interface  367  may include other components to provide application-specific functionality. 
   Examples of handheld wireless communication devices in which embodiments of the present invention may be implemented include the AccessLink™ pager and the AccessMate™ pager, both of which are manufactured by Wireless Access Inc. of Santa Clara, Calif. AccessLink™ and AccessMate™ are trademarks of Wireless Access Inc. 
   Logical View 
     FIG. 4  is a logical view illustrating various functional units provided in the wireless communication device  120  according to one embodiment of the present invention. Forward channel monitoring logic  440  receives signals from the forward channel and generates a status for use by service quality monitoring logic  410  and state machine logic  400 . Exemplary status values may include representations of the following: (1) No signal, (2) synchronization error, (3) frame error, (4) good frame, (5) reverse channel acknowledgment (ACK), (6) Messaging system ping, and (7) failed message from the wireless communication device to the messaging system. Of course, more or less status values may be used in different embodiments. For example, in one embodiment, the frame error status may be further broken down into two states, one representing a frame error at a low channel speed and another representing a frame error at a high channel speed. Further, other embodiments may distinguish between good frames that are filled and good idle frames. In any event, the forward channel monitoring logic  440 , in a known manner, interprets signals received over the forward channel and produces a status for each frame. 
   The service quality monitoring logic  410  receives status values from the forward channel monitoring logic for each frame and generates a forward channel signal quality metric for use by the state machine logic  400 . The status values have corresponding weights associated with them. The weights indicate the relative healthiness of the channel. According to one embodiment, a signal quality of 0 is the best and a signal quality of 100 is the worst. Status weights, in this example, therefore, range from 0 to 100. The status of no signal may correspond to a weight of 100, synchronization error may be assigned a weight of 80, a low speed frame error status may be associated with a weight of 60, a status of high speed frame error may be assigned a weight of 40, and a status of good frame may be assigned a weight of 0. It should be appreciated that the weight associated with a particular status may be hardcoded or may be provided as a programmable parameter, and such programmability may include over-the-air programmability. In any event, in one embodiment, the forward signal quality metric (hereinafter “Q”) is a moving average of the weights associated with the status values over a predetermined window of frames and is calculated as follows: 
           Q   =         ∑     i   =   1     N     ⁢           ⁢     Weight   i       N           
where, N is the number of frames in the window, which may also be programmable (e.g., code plug). As will be appreciated, a moving average is desirable to minimize the effect of short-term fluctuations in the forward channel signal on the current level of service indicated to the user of the wireless communication device  120 . However, various other ways of determining an appropriate forward channel signal quality metric will be apparent to those of ordinary skill in the art.
 
   The state machine logic  400  maintains a current state of the wireless communication device corresponding to the current service level. The state machine logic  400  additionally controls the transition between states of a state machine, discussed below, based upon one or more factors, such as one or more forward channel signal quality thresholds, a forward channel signal quality metric, and the status of the forward channel. According to the embodiment depicted, the state machine logic  400  receives four inputs (V 0 , V 1 , V 2 , and V 3 ) representing forward channel signal quality thresholds. As discussed further below, depending upon the current state, the relationship between Q and one or more of the forward channel signal quality thresholds, and the status of the forward channel, the state machine logic  400  may transition from one state to another causing the current state to be updated. Further, the transition from one state to another may or may not trigger some additional processing, such as updating the display, starting or stopping registration processing, re-initializing the service quality monitoring logic  410 , etc. 
   Importantly, functional units  400 ,  410 ,  420 , and  440  may be implemented in hardwired circuitry, by programming a general purpose processor, or by any combination of hardware and software/firmware. For example, according to one embodiment, the state machine logic  400  is implemented in firmware which resides in code storage  363  and is executed by processor  361   
   Exemplary State Machine 
   According to one embodiment three service levels are supported by the wireless communication device  120  and an indication is provided to the user identifying the device&#39;s current service level.  FIG. 5  is a state diagram illustrating three states in which a wireless communication device may be according to one embodiment of the present invention. According to the embodiment depicted, the wireless communication device may be in a full service state  510 , a basic service state  520 , or a storing service state  530 . 
   In the storing service state  530 , the wireless communication device  120  is outside of the messaging system&#39;s coverage area and all new messages are stored until the pager returns to a full service coverage area. The wireless communication device  120  may transition to the basic service state  520  when the forward channel signal quality is determined to be better than a predetermined threshold quality. 
   In the basic service state  520 , all new messages will be received, but not any undelivered, stored messages. According to one embodiment, stored messages may be retained by the messaging system until full service is achieved. The wireless communication device  120  may fall back to the storing service state  530  if the forward channel monitoring logic  440  indicates a status of out of ranges. The wireless communication device  120  may advance to the full service state  510  if a sufficiently good forward channel signal quality is maintained and after the reverse channel has been verified. 
   In the full service state  510  the wireless communication device  120  is in prime range. Both the forward and reverse channels have been verified to be of sufficient quality to support two-way communications. The user will receive all new messages and any undelivered messages that may have been stored. The wireless communication device  120  may return to the basic service state  520  if the forward or reverse channels become degraded. Further, the wireless communication device  120  may fall back to the storing service state  530  after receiving an indication from the forward channel monitoring logic  440  that the wireless communication device  120  is out of range. 
     FIG. 6  is a more detailed diagram of the states of  FIG. 5  according to one embodiment of the present invention. As above, arrows from one state to another represent a transition from the source state to the destination state. Actions that trigger the transition between the states are indicated above a horizontal line and the one or more actions that are taken upon the transition from the source state to the destination state are listed below the horizontal line. In the embodiment depicted, the full service state  510  comprises a primo state  640 , the basic service state  520  includes a barely in range state  620 , a good enough state  630 , and a breaking up state, the storing service state  530  includes an almost out of range state  660  and an out of range state  610 . 
   According to the embodiment depicted, the out of range (OOR) state  610  is the initial state on reset if a synchronization signal is not found on the forward channel. The state machine logic  400  may also transition to the OOR state  610  from any other state after receiving a status of OOR from the forward channel monitoring logic  440 . While the state machine is in this state an indication is provided to the user that the wireless communication device  120  is in storing service. For example, a message, such as “Storing Messages,” “Storing,” or similar message may be shown on a portion of the display. While in this state, if the forward channel monitoring logic  440  indicates good frames are detected on the forward channel, then the service quality monitoring logic  410  is re-initialized. In this manner, the past history of Q is essentially erased and the state machine can more quickly transition out of the OOR state  610  upon improvement in the forward channel&#39;s signal quality. Typically, in this state, Q ranges between signal quality values that are worse than V 3  to V 2 . Once Q is better than V 2  and a status other than OOR is received from the forward channel monitoring logic  440  the state machine may transition to the barely in range (BIR) state  620 . 
   The BIR state  620  represents a state in which the state machine has obtained a certain level of confidence in the quality of the forward channel. In this embodiment, the BIR state  620  is the initial state on reset if a synchronization signal is found on the forward channel. Other transitions to the BIR state  620  generally represent an increase in the level of confidence in the quality of the forward channel. While the state machine is in this state, an indication is provided to the user that the wireless communication device  120  is in basic service. For example, a message, such as “Basic Service,” “Basic,” or similar message may be shown on a portion of the display. Typically, in this state, Q ranges between signal quality values of V 3  to V 0 . After the signal quality has been determined to be better than V 0 , the state machine logic  400  transitions to the good enough state  630 . 
   In this embodiment, the good enough state  630  is one transition away from the Primo state  640 . In this state, very good signal quality on the forward channel has been achieved, but the reverse channel remains to be verified. While the state machine is in the Good Enough state  630 , the user is provided with an indication that the wireless communication device  120  is in basic service. In this state, Q is typically better than V 0  and no worse than V 1 . If the signal quality falls below V 1 , the state machine logic  400  transitions to the breaking up state  650 . If the signal quality remains above or equal to V 1  and the reverse channel is verified (e.g., by way of a reverse channel ACK or a registration ACK), then the state machine logic  400  transitions to the Primo state  640 . 
   According to the embodiment depicted, the Primo state  640  represents a state in which very good signal quality on the forward channel has been achieved and additionally the reverse channel has been verified. In this state, the user is provided with an indication that the wireless communication device  120  is in full service. For example, a message, such as “Full Service,” “Full,” or similar message may be shown on a portion of the display. In this embodiment, Q ranges for the Primo state  640  are better than V 0  to V 1 . Once the forward channel signal quality has degraded enough such that Q is worse than V 1 , the state machine logic  400  transitions to the breaking up state  650 . Other transitions from this state occur when there is an indication that the reverse channel has degraded (e.g., a messaging system ping is received, such as a location query or a message from the wireless communication device  120  to the messaging system failed), the forward channel has degraded (e.g., the forward channel signal quality has caused Q to become worse than V 1 ), or the forward channel has been lost (e.g., the forward channel monitoring logic  440  indicates a status of OOR). If it is the case that the reverse channel has degraded, the state machine logic  400  transitions back to the good enough state  630 . In the situation that the forward channel has merely been degraded, then the state machine logic  400  transitions to the breaking up state  650 . Finally, if it is the case that an OOR status has been received, the state machine logic  400  transitions to the OOR state  610 . 
   The breaking up state  650  is two transitions away from the Primo state  640 . This state is entered from the Primo state  640  or the good enough state  630  when Q becomes worse than V 1 . In this state, the user is provided with an indication that the wireless communication device  120  is in basic service. According to this embodiment, Q ranges from V 3  to V 0  for the breaking up state  650 . If Q becomes better than V 0 , the state machine logic  400  may transition to the good enough state  630 . If Q becomes worse than V 3 , the state machine logic  400  may transition to the almost OOR state  660 . 
   In the embodiment depicted, the almost OOR state  660  represents a state in which very poor signal quality on the forward channel has been experienced. When the state machine is in either the BIR state  620  or the breaking up state  650  and the forward channel signal quality has degraded enough for Q to be worse than V 3 , then the state machine logic  400  transitions into this state. While the state machine is in the Almost OOR state  660 , the user is provided with an indication that the wireless communication device  120  is in storing service. Q values for this state range from worse than V 3  to V 2 . When the forward channel becomes healthy (e.g., the forward signal quality is healthy for long enough for Q to become better than V 2  or a new message is received), then the state machine logic&#39;s current state is upgraded to the BIR state  620 . However, if the forward channel monitoring logic  440  indicates a status of OOR, then the state machine logic&#39;s current state is downgraded to the OOR state  610 . 
   From the above description, it should be appreciated that one feature of the present embodiment is the fact that the boundaries between the states, in terms of the forward channel signal quality thresholds that need to be achieved to transition between states, provide a graceful hysteresis mechanism to prevent a mobile device from bouncing back and forth between states. 
   Registration Processing 
   The present invention further provides a registration mechanism that achieves a balance between the usage of the wireless communication device&#39;s battery with the user&#39;s perceived service level. For example, when the a forward channel signal quality metric is better than a predetermined threshold, the registration processing aggressively tries to register the wireless communication device  120  with the messaging system in order to achieve full service. Additionally, if the forward channel signal quality metric is worse than a predetermined threshold, battery power is conserved by discontinuing registration attempts until the forward channel signal quality improves. 
     FIGS. 7A–7G  provide a flow diagram illustrating a method of registration processing according to one embodiment of the present invention. According to the embodiment depicted, registration processing begins with step  701 . At step  701 , the current state of the state machine logic  400  is tested. Based upon the current state, registration processing appropriate for that state is performed. If the current state is OOR, then OOR processing is performed at step  702 . If the current state is barely in range, then barely in range processing is performed at step  703 . If the current state is good enough, then good enough processing is performed at step  704 . If the current state is primo, then primo processing is performed at step  705 . If the current state is breaking up, then breaking up processing is performed at step  706 . If the current state is almost OOR, the almost OOR processing is performed at step  707 . Upon completion of the appropriate registration processing, the process continues again with step  701 . 
   Referring now to  FIG. 7B , exemplary OOR processing will now be described. At step  720 , it is determined if a forward channel signal quality metric (e.g., Q) is above a predetermined threshold (e.g., V 2 ) and if the status of the forward channel, as indicated by the forward channel monitoring logic  440 , for example, is not out of range. If both conditions are met, then registration with the messaging system in a manner appropriate for the communication protocol may commence at step  725 . Otherwise, registration with the messaging system is not attempted. At step  727 , the state machine logic  400  updates its current state to barely in range. 
   Exemplary barely in range processing is described with respect to  FIG. 7C . At step  730 , the forward channel signal quality metric is compared against a predetermined threshold (e.g., V 0 ). If the metric is better than the predetermined threshold registration attempts begin at step  731  and at step  732  the current state is updated to good enough. However, if the metric is not better than the predetermined threshold, then it is determined whether or not a messaging system ping, such as a location query, has been received at step  735 . If such a messaging system ping has been received, this is an indication that the messaging system is storing messages destined for the wireless communication device  120 , and registration attempts may begin at step  736 . If no messaging system pings have been received, processing may continue to step  737  where it is determined if the status indicated by the forward channel monitoring logic  440  is out of range. If the wireless communication device  120  is out of range, processing continues with step  738 ; otherwise barely in range processing is complete. At step  738  registration attempts are halted as the messaging system would not receive them and transmission would thus be a waste of battery power. Because the wireless communication device is now known to be out of range, the current state is updated to OOR. 
     FIG. 7D  is useful for describing exemplary good enough processing. According to this embodiment, at step  741 , the forward channel signal quality metric is compared to a predetermined threshold, such as V 1 . Additionally, a determination is made as to whether the reverse channel is sufficient for two-way communications. If the forward channel signal quality metric is better than or equal to the predetermined threshold and the reverse channel has been verified by the reception of an ACK from the messaging system, then registration attempts may cease at step  742  because the wireless communication device  120  has completed registration with the messaging system. At step  743 , the current state is upgraded to primo. 
   If one of the conditions of step  741  are not met, then at step  744  the forward channel signal quality metric is tested to determine if it is worse than a predetermined threshold, such as V 1 . If the condition of step  744  is met, then processing continues with step  745 ; otherwise with step  747 . At step  745 , registration attempts are halted because the level of the forward channel signal quality does not justify further attempts. At step  746 , the current state is downgraded to breaking up. 
   At step  747 , if the forward channel monitoring logic  440  indicates the forward channel is out of range, then processing continues with step  748 ; otherwise good enough processing is complete. Registration attempts are stopped at step  748  and the current state is updated to OOR at step  749 . 
   Referring now to  FIG. 7E , exemplary primo processing will now be described. If it is determined at step  750  that the reverse channel has degraded (e.g., system ping received or failed message), then processing continues with step  751 . Since the forward channel signal quality remains good, registration attempts are resumed at step  751  to again achieve primo status. In the meantime, the current status is downgraded to good enough at step  752 . 
   If there is no indication of reverse channel problems, the forward channel signal quality metric is tested at step  753 . If the forward channel signal quality metric is worse than a predetermined threshold, such as V 1 , then the current state is updated to breaking up at step  754 . Otherwise, at step  755 , if the forward channel monitoring logic  440  indicates the forward channel is out of range, then processing continues with step  756 ; otherwise primo processing is complete. At step  756 , registration attempts are halted. At step  757 , the current state is updated to OOR. 
   Exemplary breaking up processing is described with respect to  FIG. 7F . At step  760 . 1 , the forward channel signal quality metric is tested. If the forward channel signal quality metric is better than a predetermined threshold (e.g., V 0 ), then processing continues with step  761 . At step  761 , attempts to register with the messaging system are begun. At step  762 , the current state is upgraded to good enough. 
   If the forward channel signal quality metric is not better than the predetermined threshold, then at step  760 . 2 , it is compared against another predetermined threshold, such as V 3 . If the forward channel signal quality metric is worse than V 3 , for example, then processing continues with step  763 ; otherwise processing continues with step  760 . 3 . At step  763 , registration attempts are discontinued until the forward channel signal quality metric improves. At step  764 , the current state is downgraded to almost OOR. 
   At step  760 . 3 , it is determined whether or not a messaging system ping, such as a location query, has been received. If so, it is likely that the messaging system is storing new messages, therefore, registration attempts are started to notify the messaging system of the wireless communication device&#39;s current location at step  765 . Otherwise, at step  760 . 4 , a determination is made as to whether the forward channel is out of range. If the forward channel monitoring logic  440  indicates the forward channel is out of range, then processing continues with step  765 ; otherwise breaking up processing is complete. At step  765 , registration attempts are halted. At step  766 , the current state is updated to OOR. 
     FIG. 7G  is useful for describing exemplary almost OOR processing. According to this embodiment, at step  770 , the forward channel signal quality metric is compared to a predetermined threshold, such as V 2 . Additionally, a determination is made as to whether a new message has been received. If the forward channel signal quality metric is better than the predetermined threshold or a new message has been received at the wireless communication device  120 , then registration attempts may begin at step  771 . At step  772 , the current state is upgraded to barely in range. 
   If neither of the conditions of step  770  are met, then it is determined whether or not a messaging system ping, such as a location query, has been received at step  773 . If such a messaging system ping has been received registration attempts may begin at step  774 . Otherwise, at step  775 , a determination is made as to whether the forward channel is out of range. If the forward channel monitoring logic  440  indicates the forward channel is out of range, then processing continues with step  776 ; otherwise almost OOR processing is complete. At step  776 , registration attempts are halted. At step  777 , the current state is updated to OOR. 
   Alternative Embodiments 
   Many alternative embodiments are contemplated by the inventors of the present invention. For example, the inventors envision uses of the present invention in multiprotocol wireless communication devices. By way of illustration, the multiprotocol wireless communication device, may employ the teachings of the present invention to determine the service level in one or more available protocols to decide upon a currently optimal protocol. In this manner, when the multiprotocol device is in poor coverage for one communication protocol, it may automatically switch to another protocol that has better coverage for the area. 
   Certain aspects of the invention described herein have equal application to various other selective call receivers, such as cellular telephones. Additionally, aspects of the present invention may have application in both Cellular Digital Packet Data (CDPD) and Global System for Mobile Telecommunication (GSM). 
   In the foregoing specification, the invention has been described with reference to specific embodiments thereof. It will, however, be evident that various modifications and changes may be made thereto without departing from the broader spirit and scope of the invention. The specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense.