KR100491516B1 - Method and apparatus for performing preferred system selection - Google Patents

Abstract

A method and apparatus for selecting a communication system according to a geographic area in which a subscriber station is located. If the acquisition is successful, the subscriber station examines the received system identification to determine the geographic area. The subscriber station then determines whether the captured system is the most desirable system for use in that geographic area. If it is the most desirable system for use in that geographic area, the subscriber station uses the captured system to provide services. If it is not the most desirable system for use in that geographic area, the subscriber station attempts to capture a more desirable system.

Description

METHOD AND APPARATUS FOR PERFORMING PREFERRED SYSTEM SELECTION}

The present invention relates to a communication system. More specifically, the present invention relates to a new and improved method and apparatus for selecting a preferred communication system at a subscriber station that can operate in multiple geographic areas.

As mobile communication systems become widespread in society, there is a desire for larger and more sophisticated services. In order to meet the demand for capacity of a mobile communication system, a technique for multiple access to limited communication resources has been developed. The use of code division multiple access (CDMA) modulation technology is one of several techniques to facilitate communication when there are multiple system users. Other multiple access communication system techniques, such as time division multiple access (TDMA) and frequency division multiple access (FDMA), are also known in the art. However, the spread spectrum communication scheme of CDMA has significant advantages over these modulation techniques for multiple access communication systems.

The use of CDMA technology in a multiple access communication system is USP No. 13, 1990, entitled "SPREAD SPECTRUM MULTIPLE ACCESS COMMUNICATION SYSTEM USING SATELLITE OR TERRESTRIAL REPEATERS", assigned to the assignee of the present invention and referenced herein. 4,901,307. The use of CDMA technology in a multiple access communication system is also USP dated April 7, 1992 entitled “SYSTEM AND METHOD FOR GENERATING SIGNAL WAVEFORMS IN A CDMA CELLULAR TELEPHONE SYSTEM”, which is assigned to the assignee of the present invention and referenced herein. No. 5,103,459.

When a user of a subscriber station moves from one geographic area to another, the subscriber station must select a communication system to serve. There are two ways a user can operate his subscriber station when changing the geographical area. The first method is for the user to subscribe to a communication service in various regions. Thus, the subscriber station can provide a service by using any of the service providers as long as the subscriber station searches for the communication system to which the user subscribes.

Alternatively, the user may communicate by roaming service. Mobile communication providers set up contracts between them to provide customers with a service known as "roaming." A "roamer" is a subscriber station that requires service in a system operated by a mobile communication service provider to which a user is not subscribed. In general, when the subscriber station is roaming, a signal is provided to the user indicating the roaming condition. Roaming is determined as a result of comparing the system identification (SID) of the subscribed system or systems with the SID of the system providing the broadcasted service. This informs the user that the service provided to the subscriber station incurs roaming charges.

In general, because the subscriber station does not have information about the user's geographic location, the subscriber station (from among possible communication systems in a region) must select a system that provides the best service to the user in terms of service cost and quality. As the number of areas that a user wants to operate increases, so does the number of communication systems that a subscriber station should attempt to acquire. The present invention provides a method and apparatus for selecting a communication system that best suits the needs of a user.

The present invention is disclosed in detail in co-pending U.S. patent application Ser. Assume a multi-way subscriber station as such. An example embodiment is described for a subscriber station capable of transmitting and receiving CDMA signals and capable of transmitting and receiving analog signals such as AMPS and NAMPS. The invention is equally applicable to any digital communication system including TDMA, FDMA, and GSM. In addition, the present invention is equally applicable to subscriber stations that can only operate in one way (eg analog or digital).

1 is a block diagram of an exemplary multi-way subscriber station in accordance with the present invention.

2A, 2B and 2C are flow charts of an exemplary system selection method in accordance with the present invention.

In the present invention, the subscriber station maintains a list of systems, some of which are 'preferred' systems (systems available to subscriber stations), and some are 'negative' systems (subscriber stations are unavailable). System). Corresponding to each system in the list is the system identification (SID) and the corresponding acquisition variables (band, frequency, scheme, etc.). This list is referred to below as the universal system table.

The universal system table is maintained in such a way that it can easily determine which system (first or negative) covers a common geographic area. Common geographic area refers to a common communication area. In addition, systems covering a common geographic area are prioritized (ie, ranked from the most desirable to the least desirable). The subscriber station's task is to attempt to capture services on the most desirable system in the subscriber station's current geographic area. Systems typically provide services only within a limited geographic area and therefore cannot capture services in systems outside the subscriber's current geographic area.

The problem is that the subscriber station does not necessarily know where and when to turn on. Because of roaming, it may be a completely different area than before. Thus, it may not be obvious how to capture the system, not to mention the most desirable system. In an exemplary embodiment of the invention, the subscriber station maintains a list of the most recently used (MRU) systems. Attempting to capture one of these systems in the first way is very convincing. This is because the subscriber station is likely to be present at some place, not too far from where previously.

If the subscriber station cannot capture the MRU system, it may attempt to capture any preferred system in the universal system table using the appropriate acquisition variables. In an exemplary embodiment, the subscriber station first attempts to acquire at the 'easy' to obtain the system (eg, AMPS system if there is an AMPS system in the universal system table). In an exemplary embodiment, if the subscriber station fails to capture one of these systems, it attempts to capture the 'most representative' system in the universal system table. In other words, a universal system will probably include a number of systems that differ in SID and geographic area but have the same acquisition parameters (eg channel number or frequency cutoff indicator).

Once the subscriber station has acquired the system, the subscriber station can obtain the captured system's SID from the overhead message. The subscriber station uses the received SID to determine the geographic area where it is located. In an exemplary embodiment, the subscriber station obtains geographic information from the universal system table as to whether the captured system is a preferred system or a fraudulent system.

If the SID, in the universal system table, belongs to the preferred system, which is the most desirable system within that geographical area, the subscriber station uses that system to provide services. If the captured system's SID belongs to a system in the universal system table that is not the most desirable system in that geographical area, the subscriber station uses the received SID to determine the geographical area in which it is located. The subscriber station attempts to capture the most desirable system in that geographic area by making continuous acquisition attempts for the systems in the geographic area from the most desirable system to the least desirable system.

If the SID belongs to a system that does not exist in the universal system table, the subscriber station attempts to acquire other systems. The subscriber station must first return to this system if it cannot capture the system.

The features, objects, and advantages of the present invention will become more apparent from the following detailed description with reference to the accompanying drawings. Like reference numerals refer to like elements throughout the specification and drawings.

In Fig. 1, when the multi-method subscriber station (MMSS) 1 is in the system decision substate, the operation is performed by the system decision processor 8. In the system decision substate, the system decision processor 8 selects a communication system for the MMSS 1 to attempt to perform an acquisition and provide the necessary variables for the acquisition circuit. The system decision processor 8 may be implemented with a microprocessor that functions under the program control described with reference to FIG.

In an exemplary embodiment, the MMSS 1 is a dual capable of both analog transmission and reception using analog modulation and demodulation and processing circuits (analog circuits) 4 and digital transmission and reception using digital modulation and demodulation and processing circuits (digital circuits) 6. Method subscriber station. In an exemplary embodiment, the digital circuit 6 is a CDMA transmit and receive circuit. However, other forms of digital communication such as TDMA or GSM can also be used. The present invention is applicable to cellular communication systems, mobile communication systems (PCSs), and any other communication system capable of providing services to subscriber stations that can operate in multiple geographic areas.

The design of the analog circuit 4 is known in the art and is presented in detail in Mobile Cellular Telecommunication Systems of William C. Y. Lee. An exemplary embodiment of the digital circuit 6 is described in USP Nos. 4,901,307 and 5,103,459.

The most recently used (MRU) system table 9 contains a list of the systems most recently used by the MMSS 1. In an exemplary embodiment, the MRU table 9 is implemented in a nonvolatile memory that can be maintained even after the MMSS 1 is powered off. The universal system table 11 contains system variables for all communication systems that the MMSS 1 "knows about" its existence. In the exemplary embodiment, the universal system table 11 first contains information about both systems and fraudulent systems, which systems are stored according to their geographical area. In the exemplary embodiment, the universal system table 11 is implemented with nonvolatile memory that can be maintained even after the MMSS 1 is powered off.

In an exemplary embodiment, the systems stored in the universal system table 11 are grouped according to geographic regions, with each system listed within one geographic group being sequentially arranged from the most desirable system to the least desirable system. . Criteria for system sequencing may include, for example, service costs, quality of service, unique feature support, and the like. For each system, the universal system table 11 includes the necessary acquisition variables, including the system identification (SID), as well as the band, frequency, scheme, and other variables needed to perform the acquisition. In an exemplary embodiment, each system listed is labeled with whether the system is a subscriber station's available system (preferred system) or a subscriber station's unusable system (negative system).

2 is a flowchart illustrating an exemplary method of prioritizing system selection in accordance with the present invention. Upon powering up (block 20), the MMSS 1 enters the system decision substate and control passes to the system decision processor 8. In block 22, the system decision processor 8 selects an initial system to attempt to acquire, in an exemplary embodiment in accordance with the systems listed in the MRU table 9. In the exemplary embodiment, the system decision processor 8 selects the final system used to provide the service as the system for initial acquisition. In an alternative embodiment, the system decision processor 8 selects the system most often used by the MMSS 1. In another alternative embodiment, the system decision processor 8 selects the home system of the MMSS 1.

In block 22, the system decision processor 8 retrieves the necessary acquisition variables from the universal system table 11. If the system selected for initial acquisition is an analog system, the system decision processor 8 provides acquisition parameters to the analog circuit 4 and provides the required frequency information to the transceiver 3. At block 24, MMSS 1 attempts to capture the selected analog system. The transceiver 3 amplifies or downconverts the signal (if present) received via the antenna 5 in accordance with the frequency information provided by the system decision processor 8. The analog circuit 4 demodulates the signal in accordance with acquisition variables provided by the system decision processor 8.

In block 22, if the selected system is a digital system, the system decision processor 8 provides acquisition variables to the digital circuit 6 and provides the transceiver 3 with the necessary frequency information. In an exemplary embodiment, the digital system selected for acquisition is illustrated as a CDMA system. However, as mentioned above, the present invention is equally applicable to the acquisition of other digital communication systems. At block 24, MMSS 1 attempts to capture the selected CDMA system. The transceiver 3 down converts the signal (if present) received via the antenna 5 according to the frequency information provided by the system decision processor 8. The digital circuit 6 demodulates the signal in accordance with acquisition variables provided by the system decision processor 8. Demodulation of the CDMA signal is performed by the USP No. 5,103,459.

At block 26, control is returned to the system decision processor 8 at block 25 if the acquisition attempt does not succeed. In block 25, the system decision processor 8 selects the next system to be captured. In an exemplary embodiment, the MMSS 1 first attempts to capture all the systems stored in the MRU table 9. If the MMSS 1 fails to capture one of the systems stored in the MRU table 9, the MMSS 1 attempts to capture a set of systems that are identified as "easy" to capture. Easy-to-capture systems are chosen to provide quick and easy identification of the geographic area, although they are not the most desirable systems within each geographic area. In an alternative embodiment, since the availability of the AMPS system can be readily determined, the MMSS 1 will first attempt to capture the AMPS system before attempting to capture the system in the MRU table 9.

If the MMSS 1 cannot capture a system that is easy to capture, an attempt is made to the "representative" system. The representative system is a system having acquisition variables common to many other systems. Thus, by attempting to capture a representative system, the MMSS 1 is actually testing a set of geographic area hypotheses simultaneously. If none of these systems can be captured, the MMSS 1 attempts to capture the rest of the systems in the universal system table 11.

When the acquisition of the system selected by the system decision processor 8 fails, block 28 proceeds. Block 28 determines whether an acquisition was attempted for all systems in the MRU table 9. If there are systems in the MRU table 9 that have not been attempted to acquire, the system decision processor 8 selects a system from the MRU table 9 and, as described above, the analog circuit 4, the digital circuit 6 and the transceiver. Optionally provide system acquisition variables in (3). Next, an acquisition for the selected system is attempted as described above at block 24.

If a capture attempt has been made for all systems in the MRU table 9, then the MMSS 1 attempts to acquire a " fast capture " system. AMPS systems are typical examples of high speed capture systems. Although AMPS systems provide inferior services to those provided by CDMA systems in terms of service identity, it is possible to capture AMPS systems in a shorter time. In block 34, if the MMSS 1 has not attempted to capture all of the high speed acquisition systems, then in block 36, the system decision processor 8 selects the high speed acquisition system and acquires acquisition parameters from the universal system table 11; Search them. The system decision processor 9 optionally provides system acquisition variables to the analog circuit 6, the digital circuit 4 and the transceiver 3 as described above. At block 24, an acquisition is attempted for the selected system as described above.

If a capture attempt has been made on all "fast capture" systems, the MMSS 1 attempts to capture a representative system. In block 42, if the MMSS 1 did not attempt to capture all representative systems, in block 38, the system decision processor 8 selects the representative system and retrieves acquisition parameters from the universal system table 11. do. The system decision processor 8 optionally provides system acquisition parameters to the analog circuit 4, the digital circuit 6 and the transceiver 3. Acquisition for the selected system is attempted at block 24 as described above.

If a capture attempt has been made for all " representative " systems in block 42, then MMSS 1 makes a successful attempt to capture the remaining systems in the universal system table 11. In block 44, if there is a preferred system in the universal system table 11 that no acquisition was attempted, proceed to block 40. In block 40, the system decision processor 8 selects the remaining preferred system for the acquisition attempt, retrieves acquisition variables from the universal system table 11 and stores the analog circuit 4, digital circuit 6 as described above. And optionally the system acquisition variables to the transceiver (3).

Next, an acquisition is attempted for the system selected at block 24 as described above. If acquisition attempts for all preferred systems have failed, MMSS 1 temporarily turns off at block 46 and resumes the preferred system selection process at block 20 at the next opportunity. There are several possible optional operating procedures. The first possible alternative is that the MMSS 1 only powers off. A second possible alternative is for the MMSS 1 to immediately resume the priority system selection process. A third possible alternative is for the MMSS 1 to indicate a failure and to wait for user intervention.

If the acquisition is successful, the MMSS 1 receives a system identification (SID) that is broadcast by the system captured at block 27. The signal is received via the antenna 5 and provided to the transceiver 3 where the message signal is downconverted and amplified. If the captured system is analog, a message is provided to the analog circuit 4, which demodulates the signal according to the analog demodulation format and provides the system identification information to the system decision processor 8. If the captured system is CDMA, a message is provided to the digital circuit 6, which demodulates the signal according to the CDMA demodulation format and provides the system identification information to the system decision processor 8.

In block 35, the system decision processor 8 determines whether the received SID is one of the systems stored in the universal system table 11. If the captured system is unknown to the MMSS 1, the process returns to block 25, and the MMSS 1 attempts to capture another system. In an exemplary embodiment, acquisition variables of a captured but unknown system are retained by the system decision processor 8, and the system may be used if the system cannot be captured first.

If the received system identification (SID) is listed as a "negative" system in the universal system table 11, the system decision processor 8 passes control to block 25, and the MMSS 1 sends another system. Try to capture. In the preferred embodiment, the capture parameters of the captured system are held by the system decision processor 8 and the system is used if an emergency call occurs.

If the received system identification (SID) is listed in the universal system table 11, then at step 48 the system decision processor 8 determines whether it is the most desirable system in that geographic area. It may be the case that more than one system is equally desirable for use by a subscriber station. If the captured system is the most desirable system for that geographic area, then service is provided using the captured system at block 50. When the service is terminated, the system decision processor 8 updates the MRU table 9 at block 52.

If the received system identification is not the most desirable system for that geographic area, then the system decision processor 8 selects the most preferred system for that geographic area at block 54, and the analog circuit 4, as described above, Optionally provide system acquisition variables to the digital circuit 6 and the transceiver 3. In block 56, the MMSS 1 attempts to capture the most desirable system in that geographic area. If the acquisition is successful at block 58, then the captured system is the system the subscriber station expected to acquire, and MMSS 1 uses the system captured at block 60 to provide the service. In block 62, the system decision processor 8 updates the MRU table 9 at the end of the service.

If the acquisition fails, at block 64, the system decision processor 8 selects the next most desirable system for use in that geographic area. The system decision processor 8 selectively provides system acquisition variables to the analog circuit 4, the digital circuit 6 and the transceiver 3 as described above. The process is repeated until acquisition is successful and in step 60 the MMSS 1 provides the service using the captured system. In an exemplary embodiment, if no system can be captured at block 66, the MMSS 1 temporarily turns off the power at step 68 and saves battery, then at system 20 the first opportunity at the next opportunity. Start the selection process again. There are several possible alternatives in the process. The first possible alternative is that the MMSS 1 only powers off. A second possible alternative is for the MMSS 1 to immediately resume the priority system selection process. A third possible alternative is for the MMSS 1 to indicate failure and to wait for user intervention.

In an alternative embodiment, in the event of a successful acquisition at block 48, the system decision processor 8 determines whether the system is a system first. If it is a preferred system, the MMSS 1 uses the captured system to provide the service and immediately re-enters the system decision substate to see if a more desirable system can be captured in that geographic area.

In an exemplary embodiment, the information stored in the universal system table 11 is one that indicates whether the corresponding system is more desirable than the next system in the list (bit = 1) or has the same degree of desirability (bit = 0). To provide a bit. This allows for multiple priority systems within the same geographical area. Table 1 shows an exemplary method of indicating the degree of desirability of a system within a geographic area.

Table 1 SID Geographic area bits More desirable bits 1111 0 One 2222 0 0 3333 0 0 4444 0 One 5555 0 0 6666 One 0 7777 One 0 8888 One 0

In Table 1, two different geographic areas exist. Note that systems in a common geographic area are represented by geographic area bits. Thus, the systems covering the first geographic area are 1111, 2222, 3333, 4444, and 5555, and the systems covering the second geographic area are 6666, 7777, and 8888. This is indicated by a flip in the polarity of the geographic area bits.

The preference of the system within the geographic area is indicated by the more desirable polarity of the bits. Within the first geographic area, system 1111 is more desirable than system 2222. Systems 2222, 3333, and 4444 are equally preferred and all three are more preferred than 5555. Within the second geographic area, systems 6666, 7777, and 8888 are all equally preferred. It should be noted that the preferred extent of indicating the geographic area serviced by a system and capturing service through the system is exemplary and other methods of storing this information are possible.

In Table 1 above, system 1111 is referred to as the first preferred subset of SIDs for that geographic area. The systems 2222, 3333, and 4444 are equally preferred and are referred to as the second preferred subset of SIDs for that geographic area. Similarly, system 5555 is referred to as the third preferred subset of SIDs for that geographic area. As mentioned above, in the exemplary embodiment of the universal system table 11, the table consists first of both a system and a negative system. Thus, for example, system 5555 may be a negative system and may not be referred to as a third preferred subset, but rather may be an element of the negative system set for that geographic area.

The previous description of the preferred embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the inventive conceptual principles defined herein may be applied to other embodiments without utilizing new capabilities. Thus, the present invention is not limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (45)

A method of selecting a communication system for capturing via a subscriber station, the method comprising: Receiving from the first communication system a single system identification code indicating a system identification of a first communication system; And A pre-stored in the subscriber station for determining at least one other communication system operating in the same geographical area as the first communication system, the system identification code being different from the received system identification code based on the single system identification code. Referencing a table. The method of claim 1, wherein determining the at least one other communication system comprises: Comparing the received system identification code with a list of system identification codes stored at the subscriber station, wherein each stored system identification code has an associated storage geographic area indicator; And Identifying at least one other communication system having an associated storage geographic area indicator equal to the received system identification code. 3. The method of claim 2, wherein the list of system identification codes stored at the subscriber station is sorted sequentially according to a predefined user priority. The method of claim 2, Comparing the received system identification code with a first subset of preferred system identification codes having an associated storage geographic area indicator equal to the received system identification code; And Providing a service using the first communication system when the received system identification code is in the first subset of a preferred system identification code. The method of claim 4, wherein Selecting an alternate system from the first subset of the preferred system identification codes; And Attempting to acquire a service according to the alternate system if the received system identification code is not in the first subset of a preferred system identification code. 6. The method of claim 5, further comprising providing a service using the alternate system if the acquisition attempt is successful. 7. The method of claim 6, further comprising: selecting a second alternate system having an associated storage geographic area indicator equal to the received system identification code if the acquisition attempt fails; And And attempting to capture the second alternative system. The method of claim 1, wherein the step of receiving the system identification code from the first communication system, Selecting an initial system for acquisition; Attempting to capture the initial system; And Receiving the system identification code from the first communication system if the acquisition attempt is successful. The method of claim 8, Selecting an alternate system to attempt an acquisition if the acquisition attempt fails; Attempting to capture according to the alternate system. 10. The method of claim 9 wherein the step of selecting an alternate system to attempt acquisition is determined in accordance with a set of the most recently used system. 10. The method of claim 9, wherein the step of selecting an alternate system to attempt acquisition is determined in accordance with a set of systems that are expected to capture faster than other sets of lists of system identification codes. 10. The method of claim 9 wherein the step of selecting an alternate system to attempt acquisition is determined in accordance with a set of systems having acquisition parameters common to a number of other systems. The method of claim 1, Acquiring a signal from a base station belonging to the first communication system according to an acquisition parameter retrieved from a most recently used (MRU) table; And Receiving the identification code from an overhead message sent by the base station. A method of selecting a communication system for capturing via a subscriber station, the method comprising: Receiving from the first communication system a single system identification code indicating a system identification of a first communication system; A pre-stored in the subscriber station for determining at least one other communication system operating in the same geographical area as the first communication system, the system identification code being different from the received system identification code based on the single system identification code. Referencing a table; Selecting a preferred communication system in the geographic area based on a set of communication system characteristics associated with each communication system in the table; And Attempting to acquire according to the most preferred communication system. 15. The method of claim 14, wherein said communication system characteristic set includes a service cost, and said selecting step further comprises selecting a communication system that is prioritized based on said service cost associated with a communication system in said geographic area. How to feature. 15. The method of claim 14, wherein the set of communication system characteristics comprises a quality of service, and wherein the selecting step further comprises selecting a communication system that is prioritized based on the quality of service associated with the communication system of the geographic area. How to. 15. The system of claim 14, wherein the communication system characteristic set includes whether each communication system supports a unique characteristic, and wherein the selecting step is most preferred based on whether the communication system in the geographical area supports the unique characteristic. Selecting the communication system. 15. The system of claim 14, wherein the set of communication system characteristics includes whether each communication system is a preferred system, and wherein the selecting step is based on whether the communication system in the geographic area is the preferred system. The method further comprises the step of selecting. A universal system table having a predetermined parameter set indicative of a system identification code and a geographic area for each of a plurality of communication systems; And A system determination processor indicative of a system identification of the first communication system, the system determination processor configured to receive a first system identification code sent by a first communication system, the system determination processor configured to receive the first system identification code and the universal system; And select a second communication system providing a service in the same geographical area as the first communication system based on the contents of the table. The method of claim 19, A receiver configured to downconvert the received wireless signal to produce a first downconverted signal; And Further comprising a first modulation module configured to demodulate and decode the first downconverted signal including the first system identification code and to provide the first system identification code to the system decision processor. Subscriber station device. 21. The subscriber station apparatus of claim 20, further comprising a second modulation module configured to demodulate and decode a second downconverted signal received from the second communication system. 21. The system of claim 20, wherein the predetermined set of parameters further comprises acquisition parameters corresponding to the first communication system, the system decision processor selecting the first communication system from the universal system table and performing the first communication. And the receiver and the first modulation module to receive and decode the first system identification code received from a system. 23. The subscriber station apparatus of claim 22, wherein the system decision processor is configured to select a home system associated with a subscriber station apparatus as the first communication system. 23. The subscriber station apparatus as claimed in claim 22, wherein the system decision processor is configured to select a communication system most frequently used by the subscriber station apparatus as the first communication system. 23. The subscriber station apparatus as claimed in claim 22, wherein the system decision processor is configured to select a communication system most recently used by the subscriber station apparatus as the first communication system. 23. The subscriber station apparatus of claim 22, wherein the system decision processor is configured to select the first communication system based on which communication system transmits a signal that is easy for the subscriber station apparatus to capture. 23. The system of claim 22, wherein the system decision processor is configured to select the first communication system based on the number of other communication systems in the universal system table having parameters in common with the parameters of the first communication system. Subscriber station device. 21. The apparatus of claim 20, wherein the predetermined parameter set further comprises acquisition parameters corresponding to the second communication system, the system decision processor to receive and decode a second system identification code from the second communication system. And configure the first modulation module. 20. The subscriber station apparatus of claim 19, wherein the parameter sets in the universal system table are arranged by geographic area. 30. The subscriber station apparatus of claim 29, wherein the parameter sets of the universal system table associated with a communication system providing services in the same geographical area are arranged sequentially based on the preferences of each communication system. 20. The subscriber station apparatus of claim 19, wherein the universal system table comprises a nonvolatile memory. 20. The system of claim 19, wherein the predetermined set of parameters further comprises a service cost of an associated communication system, wherein the system decision processor is configured to select the second communication system based on the service cost of the second communication system. Subscriber station device, characterized in that. 20. The system of claim 19, wherein the predetermined parameter set further comprises a quality of service of an associated communication system, wherein the system decision processor is configured to select the second communication system based on the quality of service of the second communication system. Subscriber station device, characterized in that. 20. The system of claim 19, wherein the predetermined parameter set further comprises whether to support a particular feature of an associated communication system, and wherein the system decision processor is further configured to determine a second communication based on whether the second communication system supports a particular feature. And a subscriber station device configured to select a system. 20. The system of claim 19, wherein the predetermined parameter set further comprises whether the associated communication system is a preferred system, and wherein the system decision processor is further configured to determine whether the second communication system is a preferred system. And a subscriber station device. 20. The subscriber station of claim 19, wherein the predetermined parameter set further comprises whether the associated communication system is a fraudulent system, and wherein the system decision processor is configured to select a second communication system that is not a fraudulent system. Device. 20. The subscriber station apparatus of claim 19, wherein the system decision processor is a microprocessor. 20. The system of claim 19, further comprising a most recently used system table comprising a list of the most recently used systems, wherein the system decision processor is further configured to determine the first based on the list of the most recently used system tables. A subscriber station apparatus, characterized by selecting a communication system. 39. The subscriber station apparatus of claim 38, wherein the most recently used system table comprises a nonvolatile memory. 20. The apparatus of claim 19, further comprising a digital modulation module configured to demodulate and decode a received signal comprising the first system identification code and to provide the first system identification code to the system decision processor. Subscriber station device. 43. The subscriber station of claim 40 wherein the digital modulation module is a CDMA demodulation module. 41. The subscriber station apparatus of claim 40, wherein the digital modulation module is a TDMA demodulation module. 41. The subscriber station apparatus of claim 40, wherein the digital modulation module is a GSM demodulation module. 20. The apparatus of claim 19, further comprising an analog modulation module configured to demodulate and decode a received signal comprising the first system identification code and to provide the first system identification code to the system decision processor. Subscriber station device. Means for storing a universal system comprising a predetermined parameter set for each of a plurality of communication systems, the predetermined parameter set comprising: storage means for indicating a system identification code and a geographic area; And A second communication system that receives a first system identification code belonging to a first communication system and provides a service in the same geographical area as the first communication system based on the first system identification code and a list of the universal system table; Subscriber station apparatus comprising means for selecting.