JPH11262070A - Double-mode radio telephone set - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a telephone set that is operated in a ground cellular network and also operated in a satellite network. SOLUTION: This telephone set is provided with a display unit 1 and a keypad 2. The keypad 2 includes a function key group 3, that activates various functions such as display of a character message of a voice mail, when it is depressed. The function key group 3 has a function by which the user can set or revise at least part of the references for network selection.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radio telephone,
In particular, it relates to a telephone that can operate in a terrestrial cellular network and also in a satellite network.

[0002]

2. Description of the Related Art Radiotelephones have been produced that operate in both cellular and satellite communication systems.
Representative of such a radiotelephone, referred to herein as a "dual mode" radiotelephone, is a telephone that can be used in both low and medium orbit satellite communication systems.

[0003] Users located in a particular geographical location will typically utilize the network most suitable for their purpose in the area, the so-called "home network". The choice of network can be influenced by many factors, including the service area and the costs associated with using a particular network.

[0004] A service area can be considered as an area where sufficiently strong communication can be established between a user's telephone and the network to provide at least minimal service. For certain users, however, providing a high quality communication link in a limited area or at relatively few locations may be more important than a large but more variable service area.

The range available to users, such as GSM radiotelephones, is fairly large and is not limited to home networks, but may be used throughout Europe and many other networks beyond. Use of the phone outside the home network is called "roaming"
g) ".

[0006]

SUMMARY OF THE INVENTION The purpose of a satellite operator is to effectively provide a global service area. However, just as cellular system networks are experiencing difficulties in service areas, satellite operators are also subject to significant fluctuations in signal strength and interference.

[0007] Despite these difficulties, a user properly equipped with a dual-mode radiotelephone as described above may expect roaming capabilities to be greatly enhanced. Since the cost of establishing a satellite communication network is very high, telephone charges for the use of communication over a satellite communication network may be significantly higher than when communicating over a terrestrial cellular network. Will be expected. However, that is not always the case due to the high level of competition in the telecommunications market.

[0008] Thus, the user of the dual mode radiotelephone will have the right to select a network, which selection will in any case depend on a number of factors as described above. The quality of the received signal will vary over time and will depend in particular on the location of the wireless telephone receiving the signal.

At present, the selection of a particular network by the user of a dual mode wireless telephone is made by trial and error. For example, a preferred "first" network would be a home network for cost reasons, and a satellite communication network would be a second option. If the home network is tried and the service from the first network is not available, the radiotelephone will be switched by the user to call the second satellite communication network for availability. Once a second network has been found and found to be available, the user of the wireless telephone will typically commence communication on that second network. In such a situation, the user may be able to communicate on the second network, despite the possibility of the first network becoming available while continuing to use the second network. Will continue.

It is an object of the present invention to provide a dual mode radiotelephone user with improved means for selecting a network and updating it.

[0011]

SUMMARY OF THE INVENTION In accordance with the present invention, there is provided a dual mode radiotelephone operable in both cellular and satellite communication networks.
The performance standard and cost standard of the wireless telephone used as a standard for selecting a suitable telephone network for communication using the wireless telephone can be set by a user.

[0012] The radiotelephone operating in the first network may determine whether the service of the second network is available to the radiotelephone, and based on a combination of predetermined criteria. First and second
It is activated periodically to select a suitable network from the other networks.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will now be described with reference to FIG. 1 which shows only a dual mode radiotelephone. Referring to FIG. 1, the illustrated dual-mode wireless telephone has a display unit 1 and a keypad 2. The keypad 2 includes a function key group 3. When the function key is pressed, it activates various functions such as displaying a text message of a voice mail. In this embodiment, the function key also has a novel function of providing a means for allowing a user to set or change at least part of the criteria for network selection.

One option available to the user is the default setting option, which operates once without further user intervention once selected. Another option is to turn off the network selection function and then manually switch between networks.

To set the network selection function,
Each criterion is displayed on the display 1 and then selected by the function key 3. Each criterion, for example, urban or rural, outdoor or indoor, can be entered independently. Alternatively, "LEAS", which automatically provides criteria to ensure that certain user preferences are met.
T COST ”(least cost) or“ BEST SI ”
The selection "GNAL" (best signal) is shown on the display.

When the network selection function is set and the switch of the radio telephone is switched to the ready state (power-on state), a network search is started, and the network search is started by the user through the display 1 and the function keys 3. Operates according to standards.

In one combination of the criteria, the selection of the second network is made during a time period based on the toll cost, regardless of whether the first network is available during the time period based on the toll cost. Can be completely blocked.
In another combination of criteria, signal quality is of the highest priority regardless of cost, and the switching operation of the first network or the second network will provide some indication of signal strength or signal quality in either network. Can be hindered.

Once completed according to the predetermined parameters, the result of the network search is displayed on the display 1, and the user can start communication with the network simply by pressing the send button.

In situations where an unfavorable second network is used, a periodic search for the availability of the first network follows. Once the availability of the first network is confirmed and a predetermined criterion is satisfied, an indication is provided to the user that the first network is available. The notification to the user is a visual notification by the display 1 and an auditory notification by a recognizable inflection sound or monotonous sound in the receiver.

In addition to the visual and audible notifications, the radiotelephone terminates communication with the second network and starts communicating with the first network if predetermined by the user. Alternatively, upon receiving the visual and audible instructions, the user terminates communication with the second network and invokes the first network in a conventional manner via a keypad.

The decision to automatically switch from one network to another is affected by a minimum time setting for call billing, and such automatic switching will not be free to occur until the minimum telephone time has elapsed. . Similarly, if a time block is charged, a delay may be introduced to avoid switching within the time block, and a delay may be included to avoid excessive switching from one network to the other. It may be. In situations where cost is particularly important, automatic switching between networks may occur when the first network charge becomes more favorable compared to the second network charge.

At present, a considerable amount of information can be held in a wireless telephone, and the amount of detailed information recorded in the wireless telephone tends to increase. Historical time records of charges and signal quality of calls previously made from the radiotelephone may be "LEST COST" or "BEST
When "SIGNAL" is selected, "LEASTCO
Used to assist in deciding to get the "ST" or "BEST SIGNAL" option.

"LEAST COST" by user
Is set, the data stored in the memory in the wireless telephone is used in the network selection process. Following a network availability check, the stored call data is accessed and the search performed, extending the time frame around the time of the call made (eg, Tuesday at 3:25 pm), and Will find the closest equivalent call made earlier in the network. The time frame in this embodiment is 3 pm
Any call starting at 25:03, ie between 3:22 and 3:28, will be considered an equivalent call. If no equivalent call is recorded between 3:22 and 3:28, the time frame is ± 6 minutes, then ± 12
Minutes, and then spread to ± 24 minutes. If no equivalent call is found within the ± 24 minute window, the programmed default rate information is used. Next, the rates for the closest equivalent call on each network are compared,
The lowest cost network is found.

The average time for an equivalent call is interpreted as the expected duration of the call placed and the rate changes occurring during the expected call time, and is likely to affect that call. This can be expected in this way. An estimate of the minimum cost during the duration of the placed call is made and the lowest cost network is selected. Automatic switching between networks during a call to obtain the minimum cost is hindered by time delays to prevent such excessive switching.

A record of the signal quality of the previous call during the time of the placed call is also accessed, and predicting an unacceptable drop in signal quality during the placed call will result in the disconnection of the network whose quality has deteriorated. There will be.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing one embodiment of a dual mode wireless telephone of the present invention.

[Explanation of symbols]

 1 display unit 2 keypad 3 function key

Claims (12)

[Claims] 1. A dual-mode radiotelephone operable in both a cellular network and a satellite communication network, wherein the dual-mode radiotelephone is used as a basis for selecting a suitable telephone network for communication using the dual-mode radiotelephone. Dual-mode radiotelephone that is user configurable to define performance and cost criteria to be implemented. 2. A dual mode radiotelephone capable of operating in both a cellular network and a satellite communication network, wherein the dual mode radiotelephone periodically determines whether services of other networks are available when operating in a first network. A dual mode radiotelephone that is configurable by a user to check for and select a preferred network from all available networks based on a combination of predetermined performance and cost criteria. 3. The dual mode wireless telephone according to claim 1, further comprising means for notifying the user of the result of the network selection. 4. The dual mode wireless telephone according to claim 3, wherein the notification of the result of the network selection to the user is performed by a display screen. 5. The dual-mode wireless telephone according to claim 3, wherein the notification of the result of the network selection to the user is performed by a tone or a monotonous tone. 6. The dual mode wireless telephone of claim 1, wherein the user is configurable to automatically initiate communication after a successful network selection. 7. When a network other than the first network is selected as a preferred network, the wireless telephone automatically starts communication with the preferred network and ends communication with the first network. 3. The dual-mode wireless telephone of claim 2, wherein the dual-mode wireless telephone is configurable by the user to do so. 8. The dual-mode wireless telephone according to claim 1, wherein the network selection process is configurable by the user to be stored as data in a memory in the wireless telephone. . 9. The dual mode wireless device according to claim 8, wherein a historical time record of a charge for a call previously made from the wireless telephone is stored as the data in a memory in the wireless telephone. Phone. 10. The dual mode according to claim 8, wherein a historical record of signal quality for a call made previously from said wireless telephone is stored as said data in a memory within said wireless telephone. Wireless telephone. 11. The system according to claim 1, wherein said user is configurable to minimize the cost of the call placed.
0. The dual mode wireless telephone according to any one of 0. 12. The system according to claim 1, wherein said user is able to set the call to be a best signal.
The dual-mode wireless telephone according to any one of the preceding claims.