JP4242487B2 - Mobile radio terminal - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a mobile radio terminal, and more particularly to a mobile radio terminal that performs distributed processing of the software by a plurality of tasks.
[0002]
[Prior art]
In recent years, advancement and diversification of mobile communication networks have progressed, and maintenance of communication control software and faster processing have been demanded. As a countermeasure, communication control software is composed of a plurality of tasks and functions are distributed, or a plurality of CPUs are prepared and distributed processing is performed. Thereby, for example, software for user interface and communication control, or baseband processing and message control can be developed separately.
[0003]
FIG. 7 is a software configuration diagram of a control unit of a conventional mobile radio terminal. The communication control unit is the same as that of a conventional terminal and adopts an OSI layer structure. The human interface (HMI) performs dial input from the keyboard, various information display on the LCD, and the like. Layer 3 and higher layers (referred to as service layers) have a radio management function, a mobility management function, and a call processing function. The radio management function (RT: Radio Frequency Transmission Management) refers to control of a radio line, and the mobility management function (MM: Mobility Management) refers to location registration and authentication. The call processing function (CC: Call Control) refers to call connection control such as outgoing and incoming calls. It operates in accordance with 931. Layer 2 performs link access processing (LAPDM: Link Access Procedure for Digital Mobile channel). The operation conforms to 921. Layer 1 performs frame synchronization, channel coding of data frames, and instructions to the baseband processing unit. Each layer integrates and sends signals to and from the network under management control. These software runs on the real-time OS.
[0004]
Next, the operation of the mobile radio terminal will be described with reference to FIGS. FIG. 8 is a state transition diagram showing the operation of layer 1, and FIG. 9 is a schematic state transition diagram showing the operation of layer 3. FIG. 10 is an SDL diagram of layer 1, where (a) is in the “communication” state, (b) is in the “resynchronization” state, and (c) is in the “channel switching” state. FIG. 11 is an SDL diagram of layer 3, where (a) is in the “communication” state, (b) is in the “resynchronization” state, and (c) is in the “channel switching” state.
When a loss of synchronization occurs in the “communication” state, the layer 1 sends an “out of synchronization” event to the layer 3 and shifts to the “resynchronization” state to perform resynchronization. When a synchronization loss occurs in the “communication” state, the layer 3 sends a “resynchronization display” event to the service, transitions to the “resynchronization” state, and waits for resynchronization. Also, layer 1 periodically measures the electric field strengths of the local station and the neighboring base stations in the “communication” state, and notifies the result to layer 3 through a “quality display” event. When layer 3 receives a “quality indication” event in the “communication” state, it sends a “quality indication” event to the service. The service sends a “reception level indication” event to the user interface, and checks whether the electric field strength of the local station has decreased or whether the peripheral electric field strength has become stronger. If the field strengths of the local station and the surrounding base station do not meet the channel switching condition, the next “quality display” event is waited for. If the channel switching condition is met, a “channel switching request” event is transmitted to layer 3. When the layer 3 receives a “channel switching request” event in the “communication” state, the layer 3 sends a “channel switching request” event to the layer 1 and shifts to the “channel switching” state to wait for channel switching. When the layer 1 receives the “channel switching request” event in the “communication” state, the layer 1 shifts to the “channel switching” state and performs channel switching. When layer 1 is resynchronized in the “resynchronization” state, or when channel switching is successful in the “channel switching” state, a “communication channel activation display” event is sent to layer 3 and transitions to the “communication” state. If unsuccessful, a “start failure” is sent to layer 3 and a transition to the “stop” state occurs. When the layer 3 receives the “communication channel activation display” event in the “resynchronization” state or the “channel switching” state, the layer 3 shifts to the “communication” state. When the “start-up failure” event is received, “RT stop display” is sent to the service, and the state shifts to the “RT stop” state. When a “control channel activation request” event is received from the service, a “control channel activation request” event is sent to the layer 1 to shift to the “control channel activation” state. Thereafter, the state shifts to the “standby” state, and shifts to the “communication” state by incoming or outgoing.
The above operation is shown in a message sequence chart (MSC: Message Sequence Chart, hereinafter referred to as a sequence diagram).
[0005]
FIG. 12 is a sequence diagram when resynchronization succeeds after loss of synchronization occurs in the “communication” state, FIG. 13 is a sequence diagram when resynchronization fails, and FIG. 14 shows a weak field strength in the “communication” state. FIG. 15 is a sequence diagram when channel switching fails, and FIG. 15 is a sequence diagram when channel switching fails.
[0006]
[Problems to be solved by the invention]
However, the above-described conventional mobile radio terminal has a problem that an event cross between a plurality of tasks occurs.
For example, channel switching is performed when the electric field strength of the local station decreases during communication, but loss of synchronization may occur simultaneously because the electric field strength decreases. FIG. 16 is a sequence diagram showing a problem when loss of synchronization and channel switching occur simultaneously. Layer 1 sends an “out of sync” event to layer 3, but this event is not accepted in layer 3 and is discarded. Similarly, the “channel switching” event from layer 3 is not accepted by layer 1 and is discarded. After that, when resynchronization is successful, layer 1 sends a “communication channel activation display” event to layer 3, but the activated channel is not the channel specified by layer 3, but is a channel out of synchronization. As described above, an event from the upper layer and an event from the lower layer are ignored by each other, and as a result, there is a problem that a desired channel cannot be activated. In this state, the mobile radio terminal is deadlocked and cannot operate. The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a mobile radio terminal in which event crossing does not occur even when a plurality of tasks or CPUs are used.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, a mobile radio terminal according to the present invention has the following configuration. Mobile radio terminal according to claim 1 is a request or a mobile radio terminal autonomously switches the channel from the base station, the layer 1 is out of synchronization, or start-up failure or detects an abnormal state including the reception level drop Means for notifying the upper layer to that effect, and the upper layer has means for sending a channel switching request to layer 1 according to a request from the base station or a state abnormality detection from layer 1, and layer 1 further includes means for storing the channel frequency included in the channel switching request from the upper layer, has a means for determining whether the frequency channel of the currently active is included in the channel switching request, the layer 1 is the If a channel switching request with a frequency different from that of the currently active channel is received from the upper layer while the status is detected and resynchronization is in progress , Layer 1 is configured to resynchronize carried I follow the frequencies included in the channel switching request from the upper layer.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail based on illustrated embodiments.
FIG. 1 is a block diagram showing a hardware configuration of a mobile radio terminal according to the present invention. The mobile radio terminal transmits / receives radio signals to / from the antenna 1 and the radio unit 2, the modulation / demodulation process, the synchronization process, and the communication control unit 3 for exchanging control messages with the base station, and the types and contents of events between the layers. Is comprised of an event determination unit 4 for determining what is, an event memory 5 for storing events between layers, an audio processing unit 6, and a data adapter 7.
[0009]
Next, the operation of the mobile radio terminal according to the present invention will be described with reference to FIGS. FIG. 2 is an outline of a state transition diagram showing the operation of layer 1, and the part of the present invention is characterized by the transition from the “resynchronization” state to the “channel switching” state. FIG. 3 is an outline of a state transition diagram showing the operation of layer 3, which is the same as the conventional one. FIG. 4 is a layer 1 SDL diagram. The feature of the present invention is that a channel switching request is received in the “re-synchronization” state, the event content is checked, and the channel is switched. FIG. 5 is an SDL diagram of layer 3, which is the same as the conventional one.
Since the operation when the synchronization is lost in the “communication” state and the channel switching occurs independently is the same as the conventional case, the case where both occur simultaneously will be described. FIG. 6 is a sequence diagram in the case where the electric field strength of the local station decreases in the “communication” state, and synchronization loss and channel switching occur simultaneously.
[0010]
Layer 1 stores the frequency when the communication channel is activated. When the communication channel is successfully activated and shifts to the “communication” state, the electric field strengths of the local station and the neighboring base stations are periodically measured, and the result is notified to the layer 3 by a “quality display” event. When layer 3 receives a “quality indication” event in the “communication” state, it sends a “quality indication” event to the service. The service sends a “reception level indication” event to the user interface, and checks whether the electric field strength of the local station has decreased or whether the peripheral electric field strength has become stronger. If the electric field strengths of the local station and the neighboring base stations match the channel switching condition, a “channel switching request” event is transmitted to layer 3. When the layer 3 receives a “channel switching request” event in the “communication” state, the layer 3 sends a “channel switching request” event to the layer 1 and shifts to the “channel switching” state to wait for channel switching.
[0011]
Now, if a loss of synchronization occurs in the “communication” state before layer 1 receives the “channel switching request” event, an “out of synchronization” event is sent to layer 3 and the state is re-synchronized by shifting to the “re-synchronization” state. . However, in layer 3, the “out of synchronization” event is not accepted and is discarded. Subsequently, the layer 1 receives the “channel switching request” event in the “re-synchronization” state. In this case, the layer 1 accepts the event and checks whether the switching frequency included in the event is the same as or different from the currently activated frequency. To check. Only when they are different, the channel is switched to the “channel switching” state. In the same case, there is no problem even if the channel being resynchronized is activated, so the state does not change as it is. When the channel 1 is successfully switched in the “channel switching” state, the layer 1 sends a “communication channel activation display” event to the layer 3 and shifts to the “communication” state. When the layer 3 receives the “communication channel activation display” event in the “channel switching” state, the layer 3 shifts to the “communication” state.
The operation when the synchronization loss and the channel switching occur simultaneously in the “communication” state has been described above.
[0012]
Note that the operation when the communication channel activation fails during channel switching is the same as the conventional one, and the layer 1 sends an “activation failure” event to the layer 3 and shifts to the “stop” state. When the layer 3 receives the “start failure” event, it sends “RT stop display” to the service and shifts to the “RT stop” state. Upon receiving a “control channel activation request” event from the service, layer 3 sends a “control channel activation request” event to layer 1 and transitions to a “control channel activation” state. Thereafter, the state shifts to the “standby” state, and shifts to the “communication” state by incoming or outgoing.
As described above, the present invention enables a mobile radio terminal to start a desired channel after receiving and checking an event from an upper layer even if an “out of synchronization” event and a “channel switching request” event occur simultaneously. Deadlock can be prevented.
[0013]
As described above, the example in which the present invention is applied to the out-of-synchronization as a state abnormality has been described. Further, the event from the upper layer is not limited to the “channel switching request”, but may be configured to accept other events. For example, when an outgoing call and an incoming call occur simultaneously, a “call request” that is a request from an upper layer may be preferentially accepted.
In addition, if the layer 1 receives a “channel switching request” event between the time when the hardware detects the loss of synchronization and the notification to the layer 1, this loss of synchronization should be ignored. For this reason, the frequency of the channel in which the state abnormality has occurred is compared with the frequency included in the channel switching request, and the state abnormality is notified to the upper layer only in the same case.
Furthermore, although an example in which the present invention is applied to communication between a plurality of tasks has been described, the present invention may be applied to a mobile radio terminal using a plurality of CPUs. In this way, it is easy to distribute software, and development can be performed independently for each function.
[0014]
【The invention's effect】
Since the mobile radio terminal according to the present invention is configured and operates as described above, it is possible to provide a mobile radio terminal that does not cause a problem even if an event cross occurs even if a plurality of tasks or CPUs are used. It has a remarkable effect.
[Brief description of the drawings]
1 is a block diagram showing a hardware configuration of a mobile radio terminal according to the present invention. FIG. 2 is a state transition diagram of layer 1 according to the present invention. FIG. 3 is a state transition diagram of layer 3 according to the present invention. SDL diagram of layer 1 according to the present invention. FIG. 5 SDL diagram of layer 3 according to the present invention. FIG. 6 is a sequence diagram for explaining the present invention. State transition diagram of layer 1 in FIG. 9 FIG. 9 State transition diagram of conventional layer 3 FIG. 10 SDL diagram of conventional layer 1 FIG. 11 SDL diagram of conventional layer 3 FIG. Sequence diagram [Fig. 13] Sequence diagram in which resynchronization fails [Fig. 14] Sequence diagram in which channel switching succeeds [Fig. 15] Sequence diagram in which channel switching fails [Fig. 16] Sequence diagram showing conventional problems [Description of symbols] ]
1 ・ ・ Antenna, 2 ・ ・ Wireless unit, 3 ・ Communication control unit, 4 ・ ・ Event judgment unit, 5 ・ ・ Event memory, 6 ・ ・ Audio processing unit, 7 ・ ・ Data adapter

Claims (1)

A mobile radio terminal that requests a base station or autonomously switches a channel, and when layer 1 is out of synchronization, or when a malfunction is detected including a start-up failure or a decrease in reception level, notifies the upper layer And the upper layer has means for sending a channel switching request to layer 1 in accordance with a request from the base station or a state abnormality detection from layer 1, and layer 1 is further included in the channel switching request from the upper layer. Means for storing the channel frequency and means for determining whether or not the currently activated channel is the frequency included in the channel switching request, and the layer 1 detects the state abnormality and is resynchronizing. In the state, when a channel switching request having a frequency different from that of the currently active channel is received from the upper layer, layer 1 receives a check from the upper layer. Mobile wireless terminal resynchronization follow wherein row Ukoto the frequencies included in Yaneru switching request.

Images