JP3826030B2 - Interface method suitable for position communication terminal - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a position communication terminal that wirelessly transmits a current position or information necessary for deriving the current position.
[0002]
[Prior art]
In recent years, GPS (Global Positioning System) receivers have become widespread as portable devices that can accurately measure the current position and the like. Mobile phones such as PDC (Personal Digital Cellular) are widely used as portable wireless communication devices. The infrastructure of mobile phone systems has already been considerably improved, and various communication services such as packet communication are increasing. On the other hand, there is an increasing demand for accurately grasping the location of a specific person or vehicle from a remote location. Against the background of these circumstances, development of a position communication terminal, which is a device in which a GPS receiver and a mobile phone are functionally coupled, is underway.
[0003]
FIG. 6 shows an example configuration of the position communication terminal. The terminal shown in this figure has not only members / circuits such as a battery (not shown) but also three types of modules, that is, a GPS module 10, a control module 20, and a radio module 30, and two types of antennas, a GPS antenna 11 and a PDC antenna 31. is doing. Among them, the GPS antenna 11 is an antenna for receiving a positioning signal from a GPS satellite. The GPS module 10 is a module that provides a function of executing a predetermined positioning procedure based on a positioning signal, and includes an RF unit 12 and an RF unit 12 that are circuits that amplify and frequency-convert the received positioning signal. The processing unit 14 for deriving the pseudo distance or the current position by the process based on the output of the above, and a member such as a memory 13 constituted by a RAM or the like are incorporated.
[0004]
The positioning procedure in the GPS module 10 is, for example, according to a command given from the control module 20, or according to a command given from an external server via the wireless module 30 and the control module 20, or at the arrival of a predetermined positioning timing. In response. The positioning procedure is a procedure for deriving the pseudo distance or the current position based on the received positioning signal. For example, the frequency and phase synchronization with respect to the positioning signal is established, and the pseudo distance is derived from the information obtained through the synchronization control. The pseudo distance may be obtained by sampling the positioning signal over a predetermined period and storing it on the memory 13 and analyzing the frequency of the stored positioning signal. In the case of deriving the current position, the orbit information is demodulated from the positioning signal, and the current position is derived from the pseudorange and the orbit information for a predetermined number of GPS satellites or more.
[0005]
The wireless module 30 and the PDC antenna 31 are means for wireless connection with a PDC mobile phone base station or the like. The wireless module 30 is a module that provides a function of performing packet communication with the server via the wireless connection, and includes an RF unit 32 that is a circuit that performs amplification and frequency conversion of transmission / reception signals by the PDC antenna 31, A control unit 33 for controlling the communication operation according to a predetermined procedure, and a member such as a memory 34 used by the control unit 33 are incorporated. When information to be transmitted to the server, such as information on the pseudo distance derived from the GPS module 10 and the current position, is given from the control module 20, the wireless module 30 receives a predetermined packet exchange protocol such as LAPB (Link Access Protocol). -Balanced), packetize the information and send it to the server. Further, in a system that executes a positioning procedure in response to a command from the server and returns the result, or a system in which the server controls a part of the functions of the terminal, the wireless module 30 receives a command or control signal from the server. At that time, the command or control signal is supplied to the control module 20 or to the GPS module 10 via the control module 20.
[0006]
The control module 20 is a module that intervenes in the transmission of commands or control signals from the wireless module 30 to the GPS module 10 and information transmission from the GPS module 10 to the wireless module 30, such as transmission of pseudoranges or current position information. Inside, members such as a control unit 21 and a memory 22 are incorporated. The control unit 21 can have a function of controlling the GPS module 10 and the like. Further, since the wireless module 30 operates in accordance with a specific packet switching protocol such as LAPB, the control module 20, particularly the wireless module interface portion thereof, is data in the exchange of signals and information between the GPS module 10 and the wireless module 30. It needs to function as an adapter.
[0007]
That is, the wireless module 30 is a packet switching network compliant with a packet switching protocol such as LAPB, for example, a terminal device (TE) of a PDC-P (PDC-Packet) network, and its main part is schematically shown in the right half of FIG. On the other hand, on the control unit 33 of the wireless module 30, a communication control function such as a PDC-P control function (more precisely, software for realizing it) is executed. A packet switching protocol such as LAPB is requested as an information input interface from the control module 20 side. In the figure, the TE function is a layer located above the packet switching protocol such as LAPB implemented in the control unit 33 on the protocol stack, and is loaded and implemented on the hardware of the control unit 33 as a physical layer. Yes.
[0008]
Since the protocol stack on the control unit 33 side has such a structure, the protocol stack on the control unit 21 side also needs to adopt the same structure. More specifically, the hardware of the control unit 21 connected to the hardware of the control unit 33 by a cable or the like is a physical layer, the same packet switching protocol as that of the control unit 33 side is provided above it, and the packet switching protocol is further provided above it. A data adapter (ADP) function for inputting / outputting information to / from is provided. Application software that operates on the control unit 21, for example, application software that delivers information to the wireless module 30 when information such as a pseudorange or a current position is given from the GPS module 10, is more efficient than operating on the control unit 21. The information is handed over to ADP, which is the lower software.
[0009]
[Problems to be solved by the invention]
As described above, in the position communication terminal that has been conventionally developed, it is necessary to prepare a packet switching protocol and its ADP to be used on the control module side in accordance with the connection destination packet switching network of the wireless module. In addition, if the information exchange between the control module and the wireless module is only signal transmission inside the position communication terminal, it is considered unnecessary to use a packet switching protocol such as LAPB for that purpose. It is done.
[0010]
The present invention has been made in order to solve such problems, and relates to a wireless module that uses a packet switching protocol related to a packet switching network for connection with the packet switching network, and is given from the outside. The function of accepting information, particularly by modifying the software, makes it possible to abolish the control module itself and reduce the size of the terminal, and eliminate the need for signal transmission using a packet switching protocol such as LAPB inside the terminal. And that is the purpose. The present invention is more generally aimed at providing an interface method capable of achieving the above object.
[0011]
[Means for Solving the Problems]
In order to achieve such an object, the interface method according to the present invention includes (1) connecting to a packet switching network such as a PDC-P network according to a predetermined packet switching protocol such as LAPB, and sending a data packet to the packet switching network. (2) An ADP function for inputting data to be sent to the packet switching network and a TE function for sending a data packet related to the data to the packet switching network, (3) Pseudo is software that emulates the packet switching protocol when exchanging information between the ADP function and the TE function as a hierarchy positioned in parallel above the layer. Packet switching protocol such as pseudo-LAPB is software belonging to a layer located above the common physical layer. And executes on the same processing element.
[0012]
The present invention also provides (1) a positioning module that acquires and outputs a current position or information necessary for deriving the current position according to a predetermined wireless positioning procedure, such as a pseudo-range, and a wireless communication between the outside and the outside. (2) The wireless module has the control unit that is the same processing member that executes the interface method according to the present invention. Or (1) a position communication terminal comprising a circuit for wirelessly receiving a positioning signal, for example, an RF circuit for GPS, and a wireless module for wireless communication with the outside, for example, a PDC-P wireless module; ) The wireless module has the control unit as the same processing member for executing the interface method according to the present invention.
[0013]
Thus, in the present invention, the ADP function and the TE function are executed on the same physical layer, that is, on the same processing member, and the pseudo packet switching protocol as a kind of emulator is also executed on the same physical layer. Since the ADP / TE interface is realized by the pseudo packet switching protocol, for example, information transmission between different hardware such as the control unit 21 and the control unit 33 in FIG. Not. Therefore, it is not necessary to provide a member corresponding to the control module 20 in order to provide the ADP function.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. In addition, the same code | symbol is attached | subjected to the structure same as the structure shown in FIG. 6, and the overlapping description is abbreviate | omitted. In addition, redundant description of portions common to those shown in FIG. 7 in the protocol stack is avoided. And the overlapping description is abbreviate | omitted about the part which is common between embodiment.
[0015]
FIG. 1 and FIG. 2 each show a configuration of a position communication terminal according to a preferred embodiment of the present invention. First, the position communication terminal shown in FIG. 1 includes two types of modules, a GPS module 10 and a radio module 30A, and two types of antennas, a GPS antenna 11 and a PDC antenna 31, in addition to a member such as a battery (not shown). I have. A difference in appearance from the position communication terminal shown in FIG. 6 is that a module corresponding to the control module 20 is not provided in this embodiment, and the GPS module 10 and the wireless module 30A are directly connected by, for example, a serial cable or the like. Is connected. Since the wireless module 30A can be realized by hardware of the same scale as the wireless module 30, the present embodiment in which the control module 20 is not incorporated is smaller when the dimensions of the entire terminal are compared. Further, since the number of modules and the number of parts are small, the present embodiment can be manufactured at a lower cost.
[0016]
The wireless module 30A in the present embodiment is a module having an RF unit 32, a control unit 33A, a memory 34A, and the like. The control unit 33A is hardware for realizing the functions of the control unit 33 and the functions of the control unit 21 in the position communication terminal shown in FIG. 6, and is realized by an ASIC or the like. The For example, functions realized by the control unit 33 such as a function of receiving information from the GPS module 10 and a function of controlling the operation of the GPS module 10 are realized by the control unit 33A except for those that can be omitted. Similarly, the memory 34A is a memory that plays the role that the memory 34 has played in the position communication terminal shown in FIG. 6 and the role that the memory 22 has played. Therefore, it can be said that the wireless module 30A in the present embodiment is a module in which the ADP function is integrated.
[0017]
In addition, as shown in FIG. 3, the hierarchical structure of the functions realized on the control unit 33A is implemented by mounting the ADP function and the TE function on the same and common hardware as the control unit 33A, It is structured to interface with a packet switching protocol such as pseudo LAPB.
[0018]
If the position communication terminal shown in FIG. 6, that is, a terminal having the control module 20 having the control unit 21 such as a serial controller corresponding to a predetermined packet exchange protocol, information is received from the processing unit 14 of the GPS module 10. As shown in FIG. 7, the information is temporarily transferred to the physical layer level according to the packet switching protocol and transmitted by a serial cable or the like, and further the packet switching is performed on the control unit 33 side. It was necessary to take the flow of passing to the upper layer level according to the protocol. On the other hand, the pseudo packet switching protocol implemented in the control unit 33A in this embodiment is, for example, as if it is a predetermined packet switching protocol such as LAPB from the ADP side when passing information from the ADP side to the TE side. While showing the appearance as if handing over the information, and from the TE side, the appearance as if receiving information from the packet switching protocol, actually processing according to the packet switching protocol This is software or an emulator that realizes information transfer from the ADP side to the TE side by information transfer in an upper layer that is not accompanied. A true packet switching protocol is not necessary in this aspect. Since such a pseudo packet switching protocol is introduced, in this embodiment, a member corresponding to the control module 20 is not required, and the terminal can be reduced in size and price as described above.
[0019]
Next, in the position communication terminal shown in FIG. 2, the number of modules and parts are further reduced compared to the position communication terminal shown in FIG. 1, and further downsizing and cost reduction are achieved. Yes. That is, the GPS module 10 which is a module including the processing unit 14 and its memory 13 is abolished, and the RF unit 12 or a smaller module including the RF unit 12 remains. The radio module 30B roughly includes almost all of the members constituting the GPS module 10 except for the RF section 12 that is difficult to integrate into the radio module side because it handles weak high-frequency signals or functions thereof. 1 is incorporated in the wireless module 30A in the embodiment shown in FIG. For example, the processing unit 14, which is a member realized by a DSP or the like, is integrated with the control unit 33 </ b> A to become a processing / control unit 33 </ b> B in the wireless module 30 </ b> B. In addition, the hierarchical structure of functions realized on the processing / control unit 33B in the present embodiment is roughly the structure shown in FIG. As shown in this figure, in this embodiment, software (group) related to GPS processing is also executed on the common hardware which is the processing / control unit 33B.
[0020]
FIG. 5 shows a procedure executed by the radio module 30A or 30B in the preferred embodiment of the present invention for establishing a connection with the packet switching network, taking a connection to the PDC-P network as an example. In the figure, “mover” is a trademark. As shown in this figure, when a request to establish a connection related to packet communication (connect request) is generated by the application software, the mover interface mounted on the ADP side changes to the mover interface mounted on the TE side. The dialer call is made by supplying the signal, and accordingly, the mover interface on the TE side corresponds to the PDC control which is software on the control unit 33A or 33B (corresponding to “communication control” in FIGS. 3, 4 and 7). If the packet communication registration is successful through wireless communication, connection establishment / confirmation between ADP and TE is performed. In each of the embodiments described above, the part that is converted to pseudo LAPB is a part that belongs to signal exchange between ADP and TE. In FIG. 5, the corresponding part is surrounded by a thick square frame.
[0021]
In each of the above-described embodiments, the function of the control module 20 or the like is incorporated in the wireless module 30A or 30B. By utilizing this fact, it is possible to more suitably prevent potential interference with the positioning operation. The potential interference here refers to electromagnetic radiation generated by various members provided in the position communication terminal or transmission waves from the PDC antenna 31 or the like acting as colored noise when receiving a positioning signal. As a result, the sensitivity to the positioning signal is reduced. In each of the above embodiments, the members that generate electromagnetic radiation and the members that perform wireless transmission are concentrated in the wireless module 30A or 30B. Therefore, such members are scattered in the control module 20 and the wireless module 30. Compared with the terminal shown in FIG. 6, countermeasures against potential interference are easier. For example, during the positioning signal reception, the control unit 33A in the wireless module 30A sleeps and the wireless transmission is stopped, so that potential interference to the positioning signal reception can be prevented by a relatively simple method.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of a location communication terminal according to an embodiment of the present invention.
FIG. 2 is a block diagram showing a configuration of a position communication terminal according to another embodiment of the present invention.
FIG. 3 is a diagram showing an outline of a main part of a protocol stack of a wireless module in the embodiment shown in FIG. 1;
4 is a diagram showing an outline of a main part of a protocol stack of a wireless module in the embodiment shown in FIG. 2;
FIG. 5 is a diagram showing a connection establishment procedure in an example in which the present invention is applied to a position communication terminal for a system using a PDC-P network, including a portion where a pseudo packet switching protocol is used.
FIG. 6 is a diagram illustrating an exemplary configuration of a position communication terminal that has been conventionally developed.
FIG. 7 is a diagram showing an outline of a main part of a protocol stack including a physical connection between a control module and a wireless module.
[Explanation of symbols]
10 GPS module, 11 GPS antenna, 12, 32 RF unit, 13, 34A memory, 14 processing unit, 30A, 30B wireless module, 31 PDC antenna, 33A control unit, 33B processing / control unit.

Claims (3)

Connected to a packet switching network according to a predetermined packet switching protocol, and executed at a terminal that sends a data packet to the packet switching network,
A hierarchy in which a data adapter function for inputting data to be transmitted to a packet switching network and a terminal function for transmitting data packets related to the data to the packet switching network are positioned in parallel above a common physical layer Realized on the same processing member as
The pseudo packet switching protocol, which is software that emulates the packet switching protocol when exchanging information between the data adapter function and the terminal function, is assumed to be software belonging to a layer located above the common physical layer. An interface method which is executed on the same processing member. In a position communication terminal comprising a positioning module that acquires and outputs a current position or information necessary for deriving the current position according to a predetermined wireless positioning procedure, and a wireless module for wireless communication with the outside,
A position communication terminal, wherein a wireless module has the control unit as the same processing member for executing the interface method according to claim 1. In a position communication terminal comprising a circuit for wirelessly receiving a positioning signal and a wireless module for wireless communication with the outside,
A position communication terminal, wherein a wireless module has the control unit as the same processing member for executing the interface method according to claim 1.

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