WO2001013668A1

WO2001013668A1 - Method for associating discontinuous radio channel groups with service providers in wireless telephone systems

Info

Publication number: WO2001013668A1
Application number: PCT/US2000/021889
Authority: WO
Inventors: Anthony J. Sammarco; Havish Koorapaty
Original assignee: Ericsson Inc.
Priority date: 1999-08-17
Filing date: 2000-08-10
Publication date: 2001-02-22
Also published as: MY133729A; AU6630500A

Abstract

In wireless mobile communication systems, mobile terminals that need to use system resources offered by various service providers must first know what the radio channel allocations for each of the service providers are. These radio channels may be allocated continuously for each service provider or discontinuously. Service providers are associated with radio channel frequency groups when these channel frequency groups are allocated discontinuously.

Description

METHOD FOR ASSOCIATING

DISCONTINUOUS RADIO CHANNEL GROUPS WITH SERVICE PROVIDERS

IN WIRELESS TELEPHONE SYSTEMS

Cross Reference This application claims the benefit of U. S. provisional application No.

60/149,254, filed August 17, 1999.

BACKGROUND OF THE INVENTION

The present invention relates in general to commercial wireless communication systems, such as mobile communications systems, operating in a set of frequency bands with multiple service providers, and more particularly, to a method for associating discontinuous radio channel frequency groups with different service providers.

In commercial mobile wireless communication systems, such as the TIA-EIA- 136 system, various service providers or operators may provide services to mobile terminals in different market regions. Each of these service providers is allocated some radio resources or frequency groups. In any of the systems, a mobile terminal that must avail itself of services from a particular service provider must know the frequency groups allocated to the service provider.

A mechanism currently exists for informing a mobile terminal in the TIA-EIA- 136 system about the frequency groups assigned to each service provider in terms of 30 kHz radio channels, where the mapping between carrier frequencies and radio channel numbers is predefined in the specification. A message known as the Regulatory Configuration Message is sent on the broadcast control channel. This message contains a 1-bit field called the Regulatory Configuration Identifier (RCI). When this bit is 1, the grouping of radio channels follows a standard configuration. That is, the set of radio channels that are allocated to one service provider is known and the mobile terminal can then find the specific service provider by reading a control channel within the specified channel group. This standard allocation may also have discontinuous channel groups for a single service provider. When the RCI bit is 0, the radio channel groups are not standard and are indicated in an RF Channel Allocation information element within the Regulatory Configuration Message. The mobile terminals then search for a service provider under the assumption that each indicated radio channel group within the RF Channel Allocation information element can belong to a different service provider.

In many markets, it is possible for one service provider to have two or more radio channel groups allocated to it with the radio channel groups not being contiguous. In the past, such allocations have been part of the standard allocation. However, discontinuous channel groups could be used with non-standard configurations. For example, in the TIA-EIA- 136 system, a service provider may be allocated a first radio channel group having radio channel numbers 2 through 124 and also a second radio channel group having radio channel numbers 373 through 465. Because the service provider is not allocated radio channel groups having channel numbers 125 through 372, the two radio channel groups are said to be discontinuous. In such a scenario, there does not currently exist a mechanism to specify to the mobile terminal that these two channel groups belong to the same service provider.

Currently with a non-standard configuration, the mobile terminal simply treats each channel group as possibly belonging to a different service provider which results in incomplete associations of channel groups with service providers and can impede proper functioning of the system.

The format of the current Regulatory Configuration message is given in Table 1 below:

Table 1 : Regulatory Configuration Message Format A field type "M" refers to mandatory information elements and "O" refers to optional information elements. The "PV" field is a protocol version indicator. RCI - 0 indicates a non-standard channel allocation. Hence, the RF Channel Allocation Information element is present only when RCI = 0 and its format is as shown via the example set forth in Table 2 below:

Table 2: Example of RF Channel Allocation Information Element A mobile terminal that receives a Regulatory Configuration message having the RF Channel Allocation Information Element of Table 2 will assume the presence of five mobile service providers with the Channel Groups as specified. Each Channel Group information element includes two values, a first value representing the first channel in the group and a second value indicating the last channel in the group. For example, the first service provider is known to have channels 2 through 124, the second service provider is known to have channels 125 through 217, the third service provider is known to have channels

218 through 372, the fourth service provider is known to have channels 373 through 465 and the fifth service provider is known to have channels 466 through 1998. As can be seen, these message structures do not communicate to the mobile terminal that channel groups 2-124 and 373-465, for example, belong to the same service provider.

SUMMARY OF THE INVENTION

The association of discontinuous channel frequency groups with the appropriate carriers is transmitted to a mobile terminal. The message can provide either implicit or explicit notification of associations of discontinuous channel frequency groups. BRIEF DESCRIPTION OF THE DRAWINGS

Fig 1 is a block diagram of a mobile communications system utilizing the method in accordance with the invention,

Fig 2 is a flow diagram illustrating implementation of the method to associate channel frequency groups in the mobile communications system of Fig 1, and

Fig 2 is a flow diagram illustrating implementation of the method to decode the associated channel frequency groups in the mobile communications system of Fig 1

DETAILED DESCRIPTION OF THE INVENTION

The present invention is described in the context of the TIA-EIA-136 system However, it will be appreciated by those skilled in the art that the technique may be used for any wireless mobile communications system and access protocol

Fig. 1 illustrates an exemplary mobile communications system 10 implementing the method and apparatus for associating discontinuous radio channel groups with service providers in accordance with the invention The mobile communications system 10 includes a mobile terminal 12 in radio communication with a fixed network 14 for a particular service provider As is conventional in the TIA-EIA-136 system, and others, the mobile terminal 12 can communicate with numerous different service providers operating in a common geographic area Each of the different service providers is allocated groups of radio channels, as discussed above Thus each provider operates on different frequency bands Which service provider the mobile terminal communicates with depends on various factors, such as, for example, signal strength and predetermined preference of certain providers over others In Fig 1 the fixed network 14 is associated with a particular service provider Other service providers have similar network structures. The following description assumes that the mobile terminal 12 is communicating with the fixed network 14 and receives broadcast information relating to radio channel groups for the various service providers As is apparent, the method described and claimed herein could be used simultaneously by the various different service providers

The mobile terminal 12 includes an antenna 16, a transmitter/receiver 18, a programmable computational apparatus 20, a memory 22 and an input-output device 24

These various devices communicate with one another on a data bus 26 The antenna 16 is configured to send and receive radio signals between the mobile terminal 12 and the fixed network 14 The transmitter/receiver 18 receives signals from the antenna 16 and demodulates, demultiplexes and decodes the radio signals into one or more channels Such channels include a control channel and a traffic channel for speech or data The speech or data are delivered to the input-output device, such as a speaker The transmitter/receiver 18 delivers received messages from the control channel to the programmable computational apparatus 20 which controls and coordinates the functioning of the mobile terminal 10 responsive to messages on the control channel using programs and data stored in the memory 22. The programmable computational apparatus 20 also controls the operation of the mobile terminal 10 responsive to input from the input-output device 24

The input-output device 24 may include, for example, a microphone to receive speech signal input and convert it into analog electrical signals The analog electrical signals are delivered to the transmitter/receiver 18 The transmitter/receiver 18 converts the analog electrical signals into digital data, encodes the data and multiplexes this data with control messages from the programmable computational apparatus 20. This combined data stream is modulated and the resultant signal is broadcast using the antenna 16

As is apparent, various functions described with respect to specific blocks of the mobile terminal 12 may be implemented in other blocks according to the design of the particular mobile terminal The present invention is not limited to any particular mobile terminal configuration

The fixed network 14 includes a plurality of base stations, one of which 30 is illustrated in Fig. 1 The base station 30 is operatively associated with a fixed terminal 32 including a transmitter/receiver 34, a programmable computational apparatus 36 and a data storage apparatus 38 As is apparent, the fixed terminal 32 may be integrated with the base station 30. Alternatively, the fixed terminal 32, or portions thereof, may be located in a mobile switching center or other components in the fixed network 14, according to the particular fixed network design. The present invention is not limited to any particular fixed network configuration.

According to a first aspect of the present invention, a first method involves the addition of another information element to the Regulatory Configuration message shown in

Table 1 above. This first method is referred to as an explicit form of indicating channel frequency group associations, as the message "explicitly" identifies the discontinuous radio channel frequency groups. A new information element, called RF Channel Group Associations, is added to the Regulatory Configuration message as shown in Table 3 below:

The indicated protocol discriminators and message type are protocol specific fields that are part of the TIA-EIA-136 messaging protocol. However, the invention is not limited by the formats of these messages.

The RF Channel Allocation information element will not be present when RCI is non-zero. The RF Channel Group Associations information element will only be included if RF Channel Allocation is present. If these information elements are included all Channel Group information elements within the RF Channel Allocation information element that belong to the same association are sent contiguously.

The format of the RF Channel Group Associations information element is illustrated in Table 4 below:

Table 4: Format of the RF Channel Groups Associations information element

The Association field indicates the number of contiguously defined channel frequency groups (starting from the first Channel Group specified in the RF Channel Allocation Information element) that are associated to the same service provider. The number of instances of the Association field is N, where N is the number of service providers, because the channel groups are contiguous in the RF Channel Allocation information element. Again, the parameter type in Table 4 is TIA-EIA-136 protocol specific and describes the type of parameters included in the message. The explicit method of conveying channel information to a mobile terminal is described based on the following example For illustrative purposes only, it is assumed that Channel Groups shown in Table 2 are allocated as follows

1. Channel Groups 2-124 and 373-465 belong to a first service provider,

2 Channel Groups 218-372 and 466-1998 belong to a second service provider, and

3 Channel Groups 125-217 belong to a third service provider

The RF Channel Allocation and RF Channel Group Associations information elements are shown in Tables 5 and 6 below

Table 5: Example of RF Channel Allocation Information Element for Conveying

Associations

Table 6 Format of the RF Channel Groups Associations information element for the

Example in Table 5

The mobile terminal 12 uses the Regulatory Configuration message to decode the associations using the above two information elements The value of 2 in the first Association field indicates that the first two channel groups in the RF Channel Allocation information element, i e , Channel Groups 2-124 and 373-465 belong to the same service provider (i e , the first service provider) The value of 1 in the second Association field indicates that the third channel group in the RF Channel Allocation information element, i e ,

Channel Groups 125-217, belong to the same service provider (i e , the second service provider) The value of 2 in the third Association field indicates that the fourth and fifth channel groups in the RF Channel Allocation information element, i e , Channel Groups 218- 466 and 372-1998, belong to the same service provider (i e , the third service provider) It will be appreciated by those skilled in the art that any reasonable number of channel groupings in any order may be associated with any reasonable number of service providers using the explicit method

According to a second aspect of the present invention, a second method does not use any additional information elements within the Regulatory Configuration message The associations are conveyed implicitly to the mobile terminals through a novel ordering of channel frequency groups according to their associations This second method is therefore referred to as an implicit form of indicating channel frequency group associations The group associations to service providers are conveyed simply by imposing a certain ordering on the Channel Groups within the RF Channel Allocation Information Element This ordering is based on the following rules • The Channel Groups associated with a single service provider must appear contiguously.

• The Channel Groups associated with a single service provider are ordered within the RF Channel Allocation information element such that the channel numbers indicating the last channel in the group are in descending order. For example, if Channel Groups 2-124 and 373-465 belong to a single service provider, their order in the RF Channel Allocation information element will be such that Channel Groups 373- 465 appear before Channel Groups 2-124. • The Channel Group Associations must be ordered such that the lowest of the channel numbers indicating the last channel within the channel groups for each service provider must be in ascending order. For example, if one service provider has Channel Groups 2-124 and 373- 465, and the other service provider has Channel Groups 125-217, the channel groups of the service provider with the 2-124 and 373-465 must appear first in the RF Channel Allocation information element. This is because the lowest channel number indicating the last channel within a group for that service provider, which is 124, is lower than the corresponding lowest channel number, 217 for the other service provider. This ensures that the channel numbers indicating the last channel in the group for any set of consecutive groups in the RF Channel allocation information element belonging to different service providers are in ascending order. Alternatively this third rule may simply be that the condition above must be met, i. e., for any set of consecutive groups in the RF Channel Allocation information element belonging to different service providers the channel numbers identifying the last channel in the group are in ascending order. This rule allows more than one combination of channel group ordering to be used by the system while allowing unique association of service providers at the receiver. In that sense, it is a more general rule that meets the goal of the invention. Referring now to Table 7 below, an example of the implicit method is described based on the illustrated groupings used in the example set forth in Tables 5 and 6.

Table 7 Example of RF Channel Allocation Information Element for Conveying Associations According to Implicit Method

The mobile terminals follow the following rules when decoding Channel Group Associations

• When the channel number indicating the last channel of a channel group is lower than the corresponding channel number of the previous channel group in the RF Channel Allocation information element, then the two channel groups belong to the same service provider

• When the channel number indicating the last channel of a channel group is higher than the corresponding channel number of the previous channel group in the RF Channel Allocation information element, then the two channel groups belong to the different service providers

Accordingly, as 465 is greater than 124, and 124 is less than 217, the first two

Channel Groups belong to the same service provider, i e , the first service provider As 217 is less than 1998, the third Channel Group is the only group belonging to the next service provider, i e., the second service provider As 1998 is greater than 372, the fourth and fifth Channel Groups belong to the same service provider, i e , the third service provider

It is clear that using these rules the associations in the above example can be obtained by the mobile terminal In this technique the associations are implicitly conveyed without the need for an additional information element as was necessary in Method 1 The only requirement is on the ordering of Channel Groups within the RF Channel Allocation information element which already exists. It will be appreciated by those skilled in the art that the ascending and descending rules may be reversed and the Channel Groups appropriately changed to accomplish the same implicit conveyance of associations. Referring to Fig. 2, a flow diagram illustrates a program implemented in the fixed network programmable computational apparatus 36 for implementing the methods in accordance with the invention.

The program begins at a block 50 which scans for available radio channels. The channels for each particular service provider are identified at a block 52. The service providers information may also be available through other means. The identified channels are then grouped for each provider into ordered groups at a block 54. This information will be used to build the RF Channel Allocation information element such as shown in Table 2 above. A decision block 56 determines if the groups for the different service providers are continuous. If so, then the program proceeds to a block 58 to broadcast the Regulatory Configuration message (RCM). In this instance the conventional message format such as shown in Table 1 may be used.

If the radio channel groups are discontinuous, as determined at the decision block 56, then a block 60 reorders the groups and builds an Allocation Information element. Particularly, the groups would be reordered to be contiguous for each particular service provider. If explicit notification of associations is to be used, then the reordering would be done in a manner as illustrated in Table 5 above. Conversely, if implicit notification is being used, then the reordering would be in accordance with the rules described above. If explicit notification is used, then the channel group association information element is built at a block 62 as illustrated in Table 6 above. The program then proceeds to a block 64, either directly from the block 60 for implicit notification or via the block 62 for explicit notification. The block 64 builds the Regulatory Configuration message in the modified form for the explicit notification case and in the regular form for the implicit case. An illustration of the modified form is shown in Table 3 above. The modified Regulatory Configuration message is then broadcast at the block 58. A flow diagram for the decoding routine implemented in the programable computational apparatus 20 in the mobile terminal 12 is shown in Fig. 3. The program begins when the mobile terminal 12 reads the Regulatory Configuration Message at a block 70. The channel frequency groups in the Regulatory Configuration Message are identified at a block 72. A decision block 74 determines if the channel frequency groups identified in the block 72 are continuous. If not, then the discontinuous channel frequency groups for each service provider are associated with one another at a block 76. This is done using the rules discussed above. The routine then ends.

Claims

CLAIMS WE CLAIM:

1. A method for communicating associations of discontinuous RF channel frequency groups to a mobile terminal in a mobile communication system, said method comprising: transmitting a message to the mobile terminal, the message identifying the associations of discontinuous RF channel frequency groups.

2. The method of claim 1 wherein the message provides explicit notification of the associations of discontinuous RF channel frequency groups.

3. The method of claim 1 wherein the message provides explicit notification of the associations of discontinuous RF channel frequency groups by adding an additional element to an existing Regulatory Configuration message.

4. The method of claim 1 wherein said message implicitly indicates the associations of discontinuous RF channel frequency groups by transmitting the discontinuous RF channel frequency groups in a select order.

5. The method of claim 1 wherein the message provides implicit notification of the associations of discontinuous RF channel frequency groups by providing a select non-consecutive ordering of RF channel frequency groups.

6. The method of claim 1 wherein the message identifies a number of channel frequency groups and channel frequency numbers in each of the groups, the groups being in a select order so that channel frequency groups for each service provider are ordered consecutively.

7. The method of claim 6 wherein the message further identifies a number of channel frequency groups associations and a number of groups in each association.

8. The method of claim 7 wherein the number of channel frequency groups associations and the number of groups in each association corresponds to the select order.

9. The method of claim 5 wherein RF channel frequency groups associated with a particular service provider are ordered such that channel numbers indicating a last channel in the RF channel frequency group are listed in descending order.

10. The method of claim 9 wherein a lowest of channel numbers indicating the last channel in the RF channel frequency groups for each service provider are in ascending order.

11. The method of claim 1 wherein the RF channel frequency groups identify first and last channel numbers in each group.

12. The method of claim 11 wherein the associations of discontinuous RF channel frequency groups are identified by ordering channel frequency groups for each service provider consecutively.

13. A method for communicating associations of discontinuous RF channel frequency groups to a mobile terminal in a mobile communication system, said method comprising: transmitting a message to said mobile terminal, said message comprising an RF channel allocation information element and an RF channel groups associations information element, said RF channel allocation information element comprising a number of channel groups information element and a plurality of channel groups information elements, each of said channel group information elements indicating channel frequencies within each respective channel group, said RF channel groups associations information element comprising a number of channel group associations information elements and a plurality of association information elements; and associating each of said plurality of channel frequency groups to respective service providers based on said message, wherein each of said plurality of association information elements indicates which of said plurality of channel frequency groups is associated with each said respective service provider.

14. In a mobile terminal used in a mobile communication system a method for determining associations of discontinuous RF channel frequency groups, said method comprising: receiving a message, the message identifying the associations of discontinuous RF channel frequency groups; and associating each of said plurality of channel frequency groups with respective service providers based on said received message.

15. The method of claim 14 wherein the message provides explicit notification of the associations of discontinuous RF channel groups by adding an additional element in an existing Regulatory Configuration message.

16. The method of claim 14 wherein the message identifies a number of channel frequency groups and channel frequency numbers in each of the groups, the groups being in a select order so that channel frequency groups for each service provider are ordered consecutively.

17. The method of claim 16 wherein the message identifies a number of channel frequency groups associations and a number of groups in each association.

18. The method of claim 17 wherein the number of channel frequency groups associations and the number of groups in each association corresponds to the select order.

19. The method of claim 14 wherein said message implicitly indicates the associations of discontinuous RF channel groups by transmitting the discontinuous RF channel groups in a select order with channel frequency groups for a particular service provider being ordered consecutively.

20. The method of claim 19 wherein RF channel frequency groups associated with a particular service provider are ordered such that channel numbers indicating a last channel in the RF channel frequency group are listed in descending order.

21. The method of claim 20 wherein a lowest of channel numbers indicating the last channel in the RF channel frequency groups for each service provider are in ascending order.

22 A mobile communication system for communicating associations of discontinuous RF channel frequency groups to a mobile terminal comprising a controller for generating a message, the message identifying the associations of discontinuous RF channel frequency groups, and a transmitter transmitting the message to the mobile terminal

23 The mobile communication system of claim 22 wherein the message provides explicit notification of the associations of discontinuous RF channel frequency groups

24 The mobile communication system of claim 22 wherein the message implicitly indicates the associations of discontinuous RF channel frequency groups by transmitting the discontinuous RF channel frequency groups in a select order

25 The mobile communication system of claim 22 wherein the message provides implicit notification of the associations of discontinuous RF channel frequency groups by providing a select non-consecutive ordering of RF channel frequency groups

26 The mobile communication system of claim 22 wherein the message identifies a number of channel frequency groups and channel frequency numbers in each of the groups, the groups being in a select order so that channel frequency groups for each service provider are ordered consecutively

27 The mobile communication system of claim 26 wherein the message further identifies a number of channel frequency groups associations and a number of groups in each association

28 The mobile communication system of claim 27 wherein the number of channel frequency groups associations and the number of groups in each association corresponds to the select order

29 The mobile communication system of claim 25 wherein RF channel frequency groups associated with a particular service provider are ordered such that channel numbers indicating a last channel in the RF channel frequency group are listed in descending order.

30. The mobile communication system of claim 29 wherein a lowest of channel numbers indicating the last channel in the RF channel frequency groups for each service provider are in ascending order.

31. The mobile communication system of claim 22 wherein the RF channel frequency groups identify first and last channel numbers in each group.

32. The mobile communication system of claim 31 wherein the associations of discontinuous RF channel frequency groups are identified by ordering channel frequency groups for each service provider consecutively.