JP3052888B2 - Traffic information receiver - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a traffic information receiving apparatus for handling two kinds of signals, an optical signal transmitted from a road beacon and an FM multiplex signal transmitted from a broadcasting station.

[0002]

2. Description of the Related Art The optical beacon system is one of road-vehicle communication systems.
In this method, two-way communication is performed between a roadside device and a vehicle-mounted device by using spatially propagating light as a transmission medium. According to the optical beacon method, traffic information such as position data, traffic congestion data, construction data, and accident data is transmitted from the on-road device to the on-vehicle device. The time data and the like are transmitted to the on-road unit.

On the other hand, the FM multiplex system is a system for transmitting traffic information such as traffic congestion data, construction data, accident data, and the like to a vehicle-mounted device in a broadcast format. In the optical beacon system, communication with the on-vehicle device can be performed only in the limited vicinity of the installation location of the on-road device because the range of the space propagation light reaches is limited. Can be performed.

[0004] The FM multiplex system can transmit data to a large number of vehicles because the range of FM radio waves can be considerably widened. However, since useful data is commonly transmitted to a large number of vehicles, the data content is wide. It is limited to traffic information.
In actual operation, it is preferable that the in-vehicle device uses the two methods to obtain local traffic information from the road device and obtain wide-area traffic information from FM multiplex broadcasting.

[0005]

However, if the vehicle-mounted device attempts to obtain data through both methods, an FM multiplex signal receiver and an optical signal receiver are required. Since these receivers are usually independent receivers, an installation place for each receiver must be secured, and for each receiver, a CPU, a memory, an interface circuit with a navigation device main body, A power supply circuit is required, and cost reduction cannot be achieved by sharing.

Therefore, the FM multiplex signal receiver and the optical signal receiver are integrated and shared, and the nearest intersection data and traffic information of the nearby area are obtained by the optical signal receiver, and a wide range of traffic information is received by the FM multiplex signal reception. And the reception switching method
There has been suggested a shared receiver that preferentially displays the optical beacon reception status and displays the data when FM multiplex broadcast data is updated (Japanese Patent Laid-Open No. Hei 7-282390).

However, in this shared receiver, it is not clear how to handle both data when optical beacon reception data and FM multiplexed signal are received simultaneously. Normally, it is conceivable to take in one of the data preferentially, but then, the other data received during that time will be lost.

Therefore, the present invention has a single CPU,
It is an object of the present invention to realize a traffic information receiving apparatus that can capture any data even if the optical beacon reception data and the FM multiplex signal compete with each other without any loss.

[0009]

A traffic information receiving apparatus according to the present invention comprises an optical signal receiving section for receiving an optical signal transmitted from a road beacon, and an FM multiplex signal for receiving an FM multiplex signal transmitted from a broadcasting station. A receiving unit, an optical signal storage unit that temporarily stores the optical signal received by the optical signal receiving unit,
An FM multiplexed signal storage unit for temporarily storing the FM multiplexed signal received by the FM multiplexed signal receiving unit; and a reception interrupt process when the data stored in the optical signal storage unit reaches a predetermined amount. A control unit that performs a reception interrupt process when the data stored in the FM multiplex signal storage unit reaches a predetermined amount.

Since the optical signal transmitted from the road beacon is transmitted with a short period, if the reception interruption processing of the FM multiplex signal is performed, the reception interruption processing of the optical signal cannot catch up and is taken into the navigation device. There is a possibility that a desired optical signal is lost. On the other hand, FM multiplexed signals are sent with a much longer period than optical signals,
Even if the reception interruption processing of the M multiplex signal is slightly delayed and the reception interruption processing of the optical signal is performed during that time, the reception interruption processing of the FM multiplex signal can be performed with a sufficient margin.

[0011] Therefore, when the time for performing the reception interruption processing of the FM multiplex signal occurs during the reception interruption processing of the optical signal, the control unit continues until the reception interruption processing of the optical signal ends. The reception interrupt processing of the FM multiplex signal is delayed, the reception interruption processing of the FM multiplex signal is performed after the reception interruption processing of the optical signal, and during the reception interruption processing of the FM multiplex signal,
If it is time to perform an optical signal reception interrupt process,
The reception interruption processing of the FM multiplex signal is interrupted, the reception interruption processing of the optical signal is performed, and the reception interruption processing of the FM multiplex signal is restarted after the reception interruption processing of the optical signal ends. (Claim 1).

[0012] The control unit includes an optical signal editing process, and an FM signal editing process.
It is preferable to perform control so that editing processing of the multiplex signal is performed alternately. As long as the vehicle is in the reception area,
Unlike the reception interruption processing in which interruption is periodically performed, the editing processing does not need to be performed in a hurry, so that the editing processing is performed alternately. The control unit switches to a reception interrupt process by the optical signal reception interrupt processing unit when an optical signal is received during the editing process of the FM multiplex signal or the optical signal, and during the editing process of the FM multiplex signal or the optical signal. When receiving the FM multiplex signal, it is preferable to switch to the reception interrupt processing by the FM multiplex signal processing unit. If the reception interrupt processing is delayed until the editing processing is completed, data overflows in the optical signal storage unit and the FM multiplex signal storage unit, and data is lost. Therefore, the reception interruption processing is given priority. .

[0013]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 shows an in-vehicle optical head 3 for performing optical transmission with an optical beacon roadside device,
FIG. 2 is a diagram showing a state in which an FM antenna 4 that receives FM multiplex radio waves is connected to a traffic information receiving device 1 that integrates light and FM, and the traffic information receiving device 1 is connected to a navigation device main body 2.

Signals received by the optical head 3 from the optical beacon road machine (hereinafter referred to as "downlink optical signals").
The signal transmitted from the on-vehicle optical head 3 to the optical beacon roadside device (hereinafter referred to as “uplink optical signal”) is configured in frame units. Specifically, for a downlink optical signal, one frame is composed of a header (5 bytes).
And the actual data part (123 bytes) (total 12 bytes)
(8 bytes) before and after a synchronization code, a CRC code, and the like. The transmission time of one frame of the downlink optical signal is about 1 m (millisecond).

For an uplink optical signal, one frame is composed of a header (10 bytes) and an actual data (up to 59 bytes).
(A maximum of 69 bytes) before and after the connection of a synchronization code and a CRC code. One downlink optical signal and one uplink optical signal are:
This frame is composed of one or more frames.

A signal received through FM multiplex broadcasting (hereinafter referred to as "FM multiplex signal") is configured in packet units. One packet is 36-byte data including 22-byte real data and 14-byte error correction code. The transmission time of one packet is about 18 ms. FIG.
2 is a hardware configuration diagram of the traffic information receiving device 1. FIG.

The traffic information receiving apparatus 1 includes an FM receiving circuit 1
a, FM multiplex signal demodulation circuit 1b, optical beacon optical head interface (I / F) 1c, optical beacon frame detection circuit 1d for detecting an optical beacon frame received from an optical beacon roadside device, optical beacon optical head interface (I / F) F) 1e, an optical beacon frame generation circuit 1f for generating an optical beacon frame to be transmitted to the optical beacon road machine, a DMA controller 1g, a central processing unit (CP)
U) 1h, a navigation communication circuit 1i, a buffer memory 1j, and a power supply circuit 1k.

The DMA controller 1g transmits the downlink optical signal and the FM multiplexed signal received from the optical beacon roadside device to the buffer memory 1j by DMA transfer of 1 byte at a time.
Is to be stored. The buffer memory 1j is a rewritable memory, and functions as an “optical signal storage unit” and an “FM multiplexed signal storage unit”. The buffer memory 1j stores a downlink optical signal, an uplink optical signal, and an FM multiplex signal, and also stores a downlink management table and an FM multiplex management table to be described later.

The CPU 1h functions as a "control unit", and its function will be described below. FIG.
FIG. 2 is a schematic block diagram of software. CPU
The software for 1h includes the optical beacon processing unit 11 and the FM
It includes a multiplex processing unit 12 and a common processing unit 13. When the transmitted downlink optical signal is accumulated to some extent in the buffer memory 1j, the optical beacon processing unit 11 extracts the downlink optical signal by interruption, adds necessary data, and outputs it to the common processing unit 13. I do. The optical beacon processing unit 11 also has a function of generating an uplink optical signal. When the FM multiplex signal transmitted is accumulated to some extent in the buffer memory 1j,
The FM multiplex signal is taken out by an interrupt, the necessary data is added, and the signal is output to the common processing unit 13. Common processing unit 13
Takes an interface for transmission and reception with the navigation device body 2.

FIG. 4 is a detailed block diagram of the software. The optical beacon processing unit 11 includes a beacon reception interrupt processing unit 111, an editing processing unit 112, an uplink transmission processing unit 113, and a navigation request processing unit 114. When the downlink optical signal is transmitted, the DM of each byte is transmitted.
The downlink optical signal is transferred to the buffer memory 1j by the A transfer.
Is stored in Here, when the data amount for one frame becomes uniform (this state becomes every 1 msec), the beacon reception interrupt processing unit 111 generates an interrupt and checks the stored downlink optical signal. The content of the downlink management table is updated according to the result of the investigation.

Here, the downlink management table is
Data type (position data, traffic data, construction data,
For each type of accident data, etc.), the total number of frames constituting the data (data of the total number of frames is included in the downlink optical signal), the number of received frames, and a memory storing each frame Is a table in which the addresses and whether or not editing is possible (whether or not the total number of frames has been prepared) are arranged.

The edit processing unit 112 checks based on the downlink management table whether or not any type of downlink optical signal can be edited. An editing process is performed based on the content of the downlink optical signal, and a transmission frame (a transmission frame is exchanged between the optical beacon processing unit 11 and the common processing unit 13 and between the FM multiplex processing unit 12 and the common processing unit 13). (Referred to as a unit of a signal to be transmitted) and notifies the common processing unit 13 of the generated signal. This editing process is performed for each type of downlink optical signal, and the edited transmission frame has the content (actual data portion) of the downlink optical signal as it is and is transmitted to the navigation device main body 2. Is added, and if necessary, accompanying data is created and added. The “accompanying data” includes, for example, data that divides data in a wide road range and classifies the data into unit areas that are easily processed by the navigation device body 2.

On the other hand, the uplink transmission processing unit 113
When the current position information of the downlink optical signal is received once from the same beacon, an uplink optical signal is prepared and transmitted and output. The content of the uplink optical signal is, for example, an ID number of the on-vehicle device, data of a travel time since the last beacon passed (including data specifying the beacon passed last time), destination data, and the like.

The transmission of the uplink optical signal is thereafter performed at regular time intervals or at variable time intervals. However, another type of downlink optical signal (data whose content changes depending on the uplink optical signal, for example, data from the same beacon, for example, Lane notification data or traffic congestion travel time link data)
Stop transmitting uplink optical signals. If "other types of downlink optical signals" are not received,
Timeout occurs in a fixed time (for example, 2 seconds).

The navigation request processing unit 114 performs processing in accordance with a request sent from the navigation device body 2 (for example, a request for limiting the type of data to be transmitted to the navigation device body 2, a request for checking the receiver, and the like). Put the processing request data in the transmission frame. Also, it notifies the editing processing unit 112 of the processing request data. FM multiplex processing unit 12
Are the FM reception interrupt processing unit 121, the navigation request processing unit 12
2. It has an editing processing unit 123.

When the FM multiplex signal is sent, the FM multiplex signal is stored in the buffer memory 1j by DMA transfer of one byte at a time. When the data amount for one packet becomes uniform (this state becomes about every 9 ms or about 18 ms), the FM reception interrupt processing unit 121 generates an interrupt,
The FM multiplex reception data is checked, and the contents of the FM multiplex signal management table are updated for each data type according to the check result. The FM multiplex management table includes, for each data type (type such as position data, traffic congestion data, construction data, accident data, etc.), the total number of packets constituting the data, the number of received packets, and a memory of a memory storing each packet. This is a table in which addresses and editability are arranged.

The edit processing unit 123 checks whether or not any of the FM multiplex signals can be edited based on the FM multiplex management table. The editing processing is performed based on the contents of the above, a transmission frame is created, and the common processing unit 13 is notified. Navigation request processing unit 122
Performs a process according to a request sent from the navigation device main body 2 (for example, a request to limit the type of data transmitted to the navigation device main body 2, a test request for a receiver, and the like), and performs a process according to the request. The processing request of the case is put in the transmission frame. Also, the processing request is sent to the edit processing unit 1
Notify 23.

The common processing unit 13 includes a navigation transmission processing unit 13
1. A navigation reception interrupt processing unit 132 is provided. The navigation transmission processing unit 131 transmits the data to the navigation device main body 2 when at least one transmission frame to the navigation device main body 2 is ready. The navigation reception interrupt processing unit 132 receives the navigation request data received from the navigation device main body 2 and creates an editing frame.

Next, competition processing between the processing of the FM multiplex signal and the processing of the optical signal will be described. As shown in the hardware configuration diagram of the traffic information receiving apparatus 1 (FIG. 2), the traffic information receiving apparatus 1 includes only one central processing unit (CPU) 1h, so that the processing of the FM multiplexed signal and the optical Which reception interrupt processing should be performed when there is a conflict with signal processing,
Which editing process is to be performed must be determined in advance.

Therefore, according to the present invention, when a reception interrupt process for an FM multiplex signal occurs during the reception interrupt process for an optical signal, the FM interrupt is performed until the reception interrupt process for the optical signal ends. After the reception interrupt processing of the multiplex signal is delayed, the reception interruption processing of the FM multiplex signal is performed after the reception interruption processing of the optical signal, and the reception of the optical signal is performed during the reception interruption processing of the FM multiplex signal. When the time to perform the interrupt processing occurs, the F
The reception interruption processing of the M multiplex signal is interrupted, the reception interruption processing of the optical signal is performed, and the reception interruption processing of the FM multiplex signal is restarted after the termination of the reception interruption processing of the optical signal. In addition, when the editing process of the FM multiplex signal and the editing process of the optical signal compete with each other, they are alternately performed without giving priority to each other. When the processing comes in, the reception interruption processing is prioritized.

FIG. 5 is a time chart showing the flow of processing in the case where the time for performing the reception interruption processing of the FM multiplex signal occurs during the reception interruption of the optical signal. If the reception interrupt processing timing of the FM multiplex signal overlaps during the reception interrupt processing of the downlink optical signal, the reception interrupt processing of the FM multiplex signal is waited until the reception interrupt processing of the downlink optical signal ends.

The reason why the reception interruption processing of the FM multiplex signal may be waited is as follows. The reception interruption interval of the downlink optical signal is very frequent (specifically, every 1 ms as described above). On the other hand, the reception interrupt processing interval of the FM multiplex signal is relatively long (specifically, every 9 ms or 18 ms as described above). Therefore,
Even if the reception interruption processing of the downlink optical signal and the reception interruption processing time of the FM multiplex signal overlap, if the reception interruption processing of the downlink optical signal is completed, the reception interruption processing of the FM multiplex signal is performed. Often, the next packet of the FM multiplex is not received while waiting.

During the reception interruption processing of the FM multiplex signal, the reception interruption time of the next downlink optical signal is reached, and the reception interruption processing of the FM multiplex signal is performed forever. There is concern that it may not be possible,
There is no problem if the reception interruption processing of the FM multiplex signal is completed within the reception interruption interval of the downlink optical signal. In fact,
The reception interruption processing of the FM multiplex signal can be performed in a time of about 0.4 msec, and there is no such a concern as described above.

FIG. 6 is a time chart showing the flow of processing in the case where the time for performing the optical signal reception interrupt processing occurs during the reception interruption of the FM multiplex signal. If there is a time when the optical signal reception interruption process occurs during the reception interruption of the FM multiplex signal,
The reception interruption processing of the FM multiplex signal is interrupted, and the reception interruption processing of the downlink optical signal is performed.

The reason for this is that, as described above, the reception interrupt interval of the downlink optical signal is extremely frequent. FIG. 7 is a flowchart showing the flow of processing when a reception interrupt processing of an FM multiplex signal occurs during reception interruption of an optical signal (corresponding to the time chart of FIG. 5).

After the reception of the optical signal is completed (step S1), the reception interrupt processing of the optical signal is performed (step S2). If the reception of the FM multiplex signal is completed during this process (step S4),
The flag F is changed from 0 to 1 (step S5), and the reception interrupt processing of the optical signal is continued. When the reception interrupt processing of the optical signal is completed (step S6), if the flag F is 0, the interruption processing is ended. If the flag F is 1, the reception interruption processing of the FM multiplex signal is performed (step S6). Step S7).

FIG. 8 is a flowchart showing the flow of processing in the case where it is necessary to perform the reception interrupt processing of the optical signal during the reception interruption of the FM multiplex signal (corresponding to the time chart of FIG. 6). After receiving the FM multiplex signal (step T
1) The reception interruption processing of the FM multiplex signal is performed (step T2). If the reception of the optical signal is completed during this processing (step T3), the reception interruption processing of the FM multiplex signal is interrupted (step T5). ), An optical signal reception interrupt process is performed (step T).
6). When the optical signal reception interrupt processing is completed (step T
7), the reception interrupt processing of the FM multiplex signal is restarted (step T2).

FIG. 9 shows an editing process of an optical signal and an editing process of an FM multiplexed signal alternately. When an optical signal is received during the editing process of the FM multiplexed signal or the optical signal, an optical signal reception interruption is performed. It is a flowchart which shows the flow of a process which switches to a reception interruption process by a processing part. Editing of optical signal and FM
Alternating the multiplex signal editing process is performed in step U
1 and step U2. If the reception of the optical signal is completed during this editing process (step U4), the data editing process is interrupted (step U5), and the reception interrupt process of the optical signal is performed (step U6). When the optical signal reception interruption process is completed (step U7), the data editing process is restarted (steps U1 and U2), and when the editing is completed (step U3), the transmission process to the navigation device main body 2 is performed. (Step U8).

FIG. 10 shows that the editing process of the optical signal and the editing process of the FM multiplex signal are alternately performed, and the FM multiplex signal or the FM multiplex signal is received during the editing process of the optical signal.
It is a flowchart which shows the flow of a process which switches to reception interruption processing by a multiplex signal interruption processing part. Alternately performing the editing process of the optical signal and the editing process of the FM multiplex signal,
This is shown in steps V1 and V2. If the reception of the FM multiplex signal is completed during this editing process (step V
4), interrupt the data editing process (step V5), and
Multiple reception interruption processing is performed (step V6). When the optical signal reception interruption processing is completed (step V7), the data editing processing is restarted (steps V1 and V2), and when the editing is completed (step V3), transmission processing to the navigation device main body 2 is performed. (Step V8).

[0040]

As described above, according to the present invention, a single C
It has a PU and integrates and shares an FM multiplexed signal receiver and an optical signal receiver. Even if an optical beacon received signal and an FM multiplexed signal compete with each other, they capture both signals without loss. It has a unique effect that it can be performed.

[Brief description of the drawings]

FIG. 1 shows an optical head 3 mounted on a vehicle and an FM antenna 4
It is a figure which shows the state connected to the traffic information receiving apparatus 1 integrated with FM, and this traffic information receiving apparatus 1 was connected to the navigation apparatus main body 2. FIG.

FIG. 2 is a hardware configuration diagram of the traffic information receiving device 1.

FIG. 3 is a schematic block diagram of software.

FIG. 4 is a detailed block diagram of software.

FIG. 5 is a time chart showing a processing flow when a time to perform a reception interruption process of an FM multiplex signal occurs during a reception interruption of an optical signal.

FIG. 6 is a time chart showing the flow of processing when a time to execute an optical signal reception interrupt occurs during an FM multiplex signal reception interrupt;

FIG. 7 is a flowchart illustrating a process flow when a time occurs to perform an FM multiplexed signal reception interrupt during an optical signal reception interrupt;

FIG. 8 is a flowchart showing a processing flow when a time to perform a reception interrupt process of an optical signal occurs during a reception interruption of an FM multiplex signal.

FIG. 9 illustrates an optical signal reception interrupt processing unit when an editing process of an optical signal and an editing process of an FM multiplex signal are alternately performed, and an optical signal is received during the editing process of the FM multiplex signal or the optical signal. It is a flowchart which shows the flow of a process which switches to a reception interruption process.

FIG. 10 is a block diagram showing an FM multiplex signal interrupt processing unit which alternately performs an optical signal editing process and an FM multiplex signal editing process, and receives an FM multiplex signal during the FM multiplex signal or optical signal editing process. 9 is a flowchart showing a flow of a process for switching to a reception interrupt process according to the first embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Traffic information receiving device integrated with light and FM 2 Navigation device main body 3 Optical head for vehicle 4 FM antenna 1a FM receiving circuit 1b FM multiplexed signal demodulating circuit 1c Optical beacon optical head interface (I / F) 1d Optical beacon frame detecting circuit 1e Optical beacon optical head interface (I / F) 1f Optical beacon frame generation circuit 1g DMA controller 1h Central processing unit (CPU) 1i Navigation communication circuit 1j Buffer memory 11 Optical beacon processing unit 12 FM multiplex processing unit 13 Common processing unit 111 Beacon reception Interruption processing unit 112 Editing processing unit 113 Uplink transmission processing unit 114 Navigation request processing unit 121 FM reception interruption processing unit 122 Navigation request processing unit 123 Editing processing unit 131 Navi transmission processing unit 132 Navi reception interruption processing unit

Continuation of the front page (51) Int.Cl. ⁷ Identification symbol FI H04B 10/04 H04B 9/00 Y 10/06 10/14 10/26 10/28 (56) References JP-A-7-282390 (JP, A) JP-A-9-93169 (JP, A) JP-A-8-190694 (JP, A) JP-A-6-251289 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name ) H04B 1/16 H04B 10/00 G01S 1/70 G08G 1/09

Claims (3)

(57) [Claims] An optical signal receiving section for receiving an optical signal transmitted from a road beacon, an FM multiplex signal receiving section for receiving an FM multiplex signal transmitted from a broadcasting station, and an optical signal receiving section receiving the optical signal. An optical signal storage unit for temporarily storing an optical signal, an FM multiplex signal storage unit for temporarily storing an FM multiplex signal received by the FM multiplex signal reception unit, and data stored in the optical signal storage unit And a control unit that performs a reception interrupt process when the data stored in the FM multiplex signal storage unit reaches a predetermined amount, and a control unit that performs a reception interrupt process when the data stored in the FM multiplexed signal storage unit reaches a predetermined amount. In the case where the time to perform the reception interrupt processing of the FM multiplex signal occurs during the reception interruption processing, the time to perform the reception interruption processing of the FM multiplex signal is delayed until the reception interruption processing of the optical signal ends. Then, the optical signal reception interrupt processing is completed. After FM
The reception interrupt processing of the multiplexed signal is performed. When the reception interruption processing of the optical signal occurs during the reception interruption processing of the FM multiplexed signal, the reception interruption processing of the FM multiplexed signal is interrupted. , Performs optical signal reception interrupt processing,
A traffic information receiving apparatus characterized in that the reception interruption processing of the FM multiplex signal is restarted after the reception interruption processing of the optical signal ends. 2. An optical signal editing processor for editing an optical signal and passing the edited signal to a navigation device main body, and an FM multiplex signal editing processor for editing an FM multiplexed signal and passing the edited signal to the navigation device main body. 2. The traffic information receiving apparatus according to claim 1, wherein control is performed such that editing processing of an optical signal and editing processing of an FM multiplex signal are performed alternately. 3. An optical multiplexed signal or optical signal, wherein the control unit switches to a reception interrupt process by an optical signal reception interrupt processing unit when an optical signal is received during the editing process of the FM multiplex signal or the optical signal. 3. The traffic information receiving device according to claim 2, wherein when an FM multiplex signal is received during the editing process, the process is switched to a reception interrupt process by an FM multiplex signal processing unit.