JP2002141891A - Communication system device for assist synchronization and method for establishing synchronization - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a communication system, a synchronization assist device and a synchronization establishing method for performing synchronization establishment and synchronous communication at a low cost. SOLUTION: A time base read from first communication equipment is received, the received time base is stored in a storing means and the time base read from the storing means is transmitted to second communication equipment. Then the first communication equipment and the second one use the time base for mutual radio communication as common synchronization timing information.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a communication system for establishing synchronization between wireless communication devices, for example.
The present invention relates to a synchronization assist device and a synchronization establishment method.

[0002]

2. Description of the Related Art With the development of wireless communication technology, in particular, the emergence of a new wireless transmission system, high-speed communication has become possible, and accordingly, the frequency used for wireless communication has been increasing. Since a radio communication device using such a high frequency operates with a high-speed clock, it is necessary to adjust its phase to establish synchronization between the devices.

In particular, in a radio communication apparatus employing a CDMA (code division multiple access) system, it is difficult to establish "initial synchronization", and usually, some kind of synchronization control means (for example,
Initial synchronization establishing device).

[0004]

However, as the transmission speed (transmission rate) of a wireless communication device increases,
There is a problem that the performance requirement for the device for establishing the initial synchronization becomes severe, and satisfying the requirement may cause an increase in the cost of the entire device.

In an apparatus operating with a high-speed clock, the initial synchronization technique becomes important. However, the conventional synchronization control means has a problem that precise and quick timing adjustment between apparatuses cannot be performed.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and has as its object to eliminate the need for incorporating a device for synchronization in a communication device, thereby achieving synchronization establishment and synchronous communication at low cost. To provide a communication system, a synchronization auxiliary device, and a synchronization establishment method capable of performing the above-mentioned operations.

It is another object of the present invention to provide a communication system, a synchronization auxiliary device, and a method for establishing synchronization, which can reliably and easily establish initial synchronization in a device operating with a high-speed clock.

[0008]

In order to achieve the above object, the present invention relates to a communication system comprising a first communication device and a second communication device for performing wireless communication with each other. Receiving means for receiving the time base read from the communication device, storage means for storing the received time base, and transmission means for transmitting the time base read from the storage means to the second communication device, The first communication device and the second communication device provide a communication system that uses the time base as common synchronization timing information for the wireless communication.

According to the present invention having such a configuration, in order to establish synchronization between wireless communication devices, it is not necessary to provide an initial synchronization establishing device in each wireless communication device, and it is possible to quickly establish synchronization at low cost.

Another aspect of the present invention is a synchronization auxiliary device used in a communication system including a first communication device and a second communication device for performing wireless communication with each other, and receives a time base from the first communication device. Means, means for storing the received time base, and means for transmitting the stored time base to the second communication device, wherein the time base communicates with the first communication device in a second communication mode. Provided is a synchronization assist device that is common synchronization timing information between devices.

[0011] With the synchronization assisting device according to the other aspect of the invention, it is possible to quickly establish synchronization and perform synchronous communication between communication devices.

According to a further aspect of the present invention, there is provided a method for establishing synchronization in a communication system including a first communication device and a second communication device for mutually performing wireless communication, wherein a time base is received from the first communication device. And a step of storing the received time base; and a step of transmitting the stored time base to the second communication device, wherein the first communication device and the second communication device There is provided a synchronization establishment method for establishing mutual synchronization by using a time base as common synchronization timing information.

According to such a method of establishing synchronization, not only low-cost and quick synchronization can be established between communication apparatuses, but also initial synchronization can be easily established.

[0014]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a diagram schematically showing how synchronization is established between devices according to an embodiment of the present invention. Here, an example is shown in which synchronization establishment is applied to wireless communication between a BS (broadcast satellite) tuner and a television receiver. In FIG. 1, a BS antenna 101 (usually a BS converter is directly connected) is fixed to an outer wall of a building (user home) 100, and a signal received there is
Via a cable (coaxial cable) 110, the building 100
Antenna terminal A of BS tuner 102 installed inside
It is taken into the main body of the BS tuner 102 from (106).

The BS tuner 102 is, here, a wireless BS tuner. Therefore, an antenna 103 is provided above the tuner, and a radio wave is transmitted from the antenna to a television receiver described later. Also, B
The S tuner 102 has an infrared transmission / reception unit 105, and transmits a signal using an infrared ray (arrow in the figure) as a transmission medium to and from a bidirectional infrared remote controller 104 (hereinafter, also simply referred to as a remote controller) as a synchronization auxiliary device. Send and receive. The specific contents of data exchanged using infrared rays will be described later.

On the other hand, in one corner of the building 100, a television receiver 121 is placed.
Also has an infrared transmission / reception unit 125 similarly to the above-mentioned BS tuner 102. And also the television receiver 121,
Using this infrared transmitting / receiving section 125, the remote controller 104
The transmission and reception of a signal using infrared rays are performed between the device and the device. Note that an antenna 122 for transmitting and receiving radio waves to and from the BS tuner 102 is connected to the television receiver 121.

FIG. 2 is a block diagram showing the configuration of the bidirectional infrared remote controller functioning as a synchronization assist device according to the present embodiment. Two-way infrared remote controller 10 shown in FIG.
4 is the BS tuner 102 and the television receiver 12 described above.
Infrared transmission / reception unit 1 for performing infrared communication with
04a. Note that this infrared transmitting / receiving unit 104a
Comprises an infrared transmitting unit 204 and an infrared emitting unit 205.

The time base unit 209 stores time information (timing information) as a reference for a predetermined operation, as described later.
The time base is stored, and a high-precision clock signal generated using a crystal oscillator is continuously received from the crystal oscillation circuit 210. The remote controller also includes a button (not shown) for the user to perform command transmission and the like and a key interface (I / F) unit 202.
And a display unit 203 for visually displaying predetermined information to the user.

A central control unit (CPU) 206 controls the entire remote controller, and reads out a read-only memory (R) in advance.
It operates according to a program indicating a predetermined processing procedure stored in the OM 207. A random access memory (RAM) 208 is used to store a radio frequency channel and the like, which will be described later. When data is moved in transmission / reception processing, it is used as a temporary memory for temporarily storing the data.

The above-mentioned CPU 206 and ROM 20
7, the RAM 208, the infrared transmitting unit 204, the infrared emitting unit 205, the time base unit 209, and the like are mutually connected via a CPU bus 250 as shown in FIG. 1, and exchange predetermined data.

FIG. 3 shows a wireless B according to the present embodiment.
FIG. 3 is a block diagram illustrating an internal configuration of an S tuner. As described above, the BS tuner 102 shown in FIG. 1 has an antenna terminal A for receiving a signal received by the BS antenna.
(106), and the received signal 303 passing therethrough is
It is sent to BS tuner section 302. The tuner 302 extracts predetermined video data (video signal of a channel desired by the user) from the received signal 303 according to, for example, channel setting information sent from the outside, and outputs the same. It is. Therefore, the BS tuner unit 302 includes a detector, a filter, and a video amplifier (not shown).

From the television receiver 121 to the BS tuner 10
2, channel setting information is transmitted using a radio frequency channel (frequency) described later. The information is received by the antenna 103 and input to the baseband demodulation unit 317 via the RF reception unit 316. Then, baseband demodulation section 317 performs a predetermined demodulation process on the input signal, and outputs a “TV CH setting” signal as broadcast channel setting information to BS tuner section 302.

On the other hand, BS tuner section 302, having received the above-mentioned "TV CH setting" signal, selects a video signal corresponding to the channel indicated by the signal and transmits it to baseband modulation section 315 as "TV video data". send. The video data input to the baseband modulator 315 is subjected to a predetermined modulation process, and then transmitted from the antenna 103 to the television receiver 121 via the RF transmitter 314. Note that a radio frequency channel described later is also used for transmitting the video data.

The infrared transmitting / receiving unit 105 includes the infrared transmitting unit 3
07 and an infrared light emitting unit 308, and exchanges information with the remote controller 104 using infrared light. The specific contents of this information will be described later. Further, the time base unit 310 stores time information (specifically, the television receiver 121) serving as a reference for the operation of the present BS tuner.
And a time base as timing information necessary for performing synchronous communication with the time base. Then, the crystal oscillation circuit 309 generates a high-accuracy clock signal for synchronous communication based on the time base, and continuously supplies the clock signal to the time base unit 310.

The frame timing generation section 311 generates the timing of the transmission frame of the video data, and the scramble code generation section 312 generates a scramble code to be used for the video signal to be transmitted and sends it to the baseband modulation section 315 and the like. Send and send and receive infrared transmission / reception unit 105
Output to Then, the scramble code is transmitted from the infrared transmitting unit 307 to the remote controller 104 as described later.

A central control unit (CPU) 304 controls the entire BS tuner, and is a read-only memory (RO).
A program indicating a predetermined processing procedure executed by the CPU 304 is stored in the M) 305 in advance. Also, the write / read memory (RAM) 306 is a CP
While the U304 is executing the program, it is used for storing data during the calculation as needed, and for moving data necessary for infrared transmission / reception processing.

As shown in FIG. 3, the CPU 304,
ROM 305, RAM 306, infrared transceiver 105,
The time base unit 310 and the like are mutually connected via a CPU bus 350 and exchange predetermined data.

FIG. 4 is a block diagram showing a configuration of the television receiver according to the present embodiment. In addition, most of the components of the television receiver shown in FIG.
Since the configuration is the same as that of the tuner, the description of the same components will be omitted, and only different components will be described.

As shown in FIG. 4, the present television receiver 121
Has a TV image receiving unit 402, and a broadcast channel selected by a user using a channel selector (not shown) is output to the baseband modulation unit 406 as a “TV CH setting” signal. . Therefore, as described above, from the television receiver 121 to the BS tuner 102,
Channel setting information is transmitted using a radio frequency channel (frequency) described later.

BS tuner 1 receiving channel setting information
02, as described above, selects a video signal corresponding to the broadcast channel set on the television receiver side from the signals received by the BS antenna, and selects it using a predetermined radio frequency channel. The data is transmitted to the television receiver 121.
As a result, the television receiver 121 uses the antenna 122 to
The video signal transmitted from the BS tuner 102 is received.

As described above, the video signal received by antenna 122 is input to baseband demodulation section 407 via RF reception section 405 of television receiver 121. Then, baseband demodulation section 407 performs a predetermined demodulation process on the input video signal, and sends it to TV image receiving section 402 as “TV video data”.

The TV receiver 402 has a display unit such as a CRT (cathode ray tube) or a liquid crystal display (LCD), like a normal TV receiver (for example, a terrestrial television). An image projected on the display unit can be viewed.

Therefore, a method for establishing synchronization according to the present embodiment using a two-way infrared remote controller as a synchronization auxiliary device will be described in detail. FIG. 5 shows the BS tuner 1
2 is a schematic flowchart showing a flow until wireless communication is established between the TV receiver 02 and the TV receiver 121. The individual processing shown in FIG. 5 will be described later with reference to a detailed flowchart.

First, in order to set the remote controller, in step S101 of FIG.
From 02, the wireless communication timing and wireless communication parameters to be described later are set for the remote controller 104. When the setting of the remote controller is completed, the TV receiver 121 is set (wireless portion setting) as the TV setting (step S102).

In step S103, the BS tuner 10
2 and the TV receiver 121 are confirmed to have established synchronization, and if synchronization has not been established, step S10 is performed again.
Returning to step 1, the remote controller is set. However, if the establishment of synchronization can be confirmed, the above setting process (setting operation)
To end.

FIG. 6 is a flowchart showing a detailed procedure of the remote controller setting process according to the present embodiment. In step S201 of the figure, when the user operates a predetermined key of the remote controller 104, the CPU 206 responds to the operation (command) transmitted via the key I / F unit 202 (see FIG. 2). 104 infrared transmission unit 20
4 transmits an initial setting start command to the BS tuner 102 using infrared rays as a transmission medium. In the following description, the infrared transmitting unit and the infrared emitting unit will be appropriately referred to as an infrared I / F.

The infrared receiver 308 of the BS tuner 102
However, upon receiving the above-mentioned initialization setting command, the CPU 304 of the BS tuner 102 reads the count value in the time base unit 310 according to the command (step S202). Then, the following step S203
Then, the time base value read in step S202 is transmitted from the infrared transmitting unit 307 of the BS tuner 102 to the remote controller 104.

In the next step S204, the remote controller 104
Loads the time base count value received by the infrared light receiving unit 205 into the time base unit 209. After that, the time base unit 209 of the remote controller 104 receives a clock from the built-in crystal oscillation circuit 210 and starts a predetermined count (step S205).

The BS tuner 102 determines in step S206
In step, transmission of a wireless transmission / reception channel (frequency) and a scramble code as wireless communication parameters stored in the ROM 305 in advance from the infrared transmission unit 307 toward the remote controller 104 is started. As a result, the remote controller 104 loads the wireless transmission / reception channel and the scramble code received via the infrared light receiving unit 205 into the RAM 208 in step S207.

In this way, the remote controller 104
In the tuner 102, a time base value as time information, which is a reference for operation, is obtained, and at the same time, a channel for wireless transmission and reception and a scramble code are obtained (received). And
The remote control 104 receives from the BS tuner 102,
These time base values and the like are provided to the TV receiver 121 side in accordance with the procedure described below.

FIG. 7 is a flowchart showing a detailed procedure of the setting process of the TV receiver according to the present embodiment. When the remote controller 104 finishes writing the wireless transmission / reception channel, scramble code, and the like received from the tuner to a predetermined storage area (memory), the remote controller 104 proceeds to step S in FIG.
At 301, “TV setting started?” Is displayed on the display unit 203 of the remote controller 104. This is a display process for notifying the user that the preparation for setting the TV receiver 121 has been completed.

In step S302, CPU 206 of remote controller 104 determines whether or not the user points remote controller 104 at TV set 121 and presses the "Yes" key on the remote controller. If there is a key press here (key I
The / F unit 202 notifies the CPU 206 that the "Yes" key has been pressed.) In step S303, the remote control 104
A TV initial setting start command is transmitted to the receiver 121.

CPU 206 of remote controller 104
Reads the time-base count value, which has started counting as described above, from the time base unit 209 (step S304), and in step S305, reads the time base value from the infrared transmitting unit 204 to the TV receiver 1.
21.

In step S306, the TV receiver 121
Receives the time-base count value from the infrared light receiving unit 418 following the above-described initialization setting start command. The CPU 414 of the TV receiver 121 adds the infrared transmission / reception delay value m stored in the ROM 415 in advance to the count value (this will be described later).
Is loaded into the time base unit 409.

As a result, the time base unit 409 starts a predetermined count using the clock signal from the crystal oscillation circuit 408 connected thereto (step S30).
7).

In step S 308, the CPU 206 of the remote controller 104 reads the wireless transmission / reception channel (frequency) and the scramble code already loaded (stored) in the RAM 208 and sends them to the infrared transmission unit 204.
To the TV receiver 121 via the.

As a result, the TV receiver 121 receives the wireless transmission / reception channel (frequency) and the scramble code transmitted from the remote controller 104 by the infrared receiving section 418 in step S309. In addition, the CPU 414 of the TV receiver 121 loads the wireless transmission / reception channel and the scramble code into the transmission / reception channel setting unit 413 and the scramble code generation unit 412, and starts the reception operation.

FIG. 8 is a flowchart showing a procedure for confirming synchronization establishment according to the present embodiment. In step S401 of the figure, the TV image receiving unit 402 of the television receiver 121
Determines whether valid video data has been received, and if the video data is valid, notifies the CPU 414 of that fact.

The CPU 414 of the television receiver 121 receives the above notification and starts wireless transmission. That is, the television receiver 121 is connected to the BS tuner 1 via a wireless line.
02, a "wireless connection confirmation request" is transmitted (step S4).
02). Upon receiving the “wireless connection confirmation request”, the BS tuner 102 transmits a “confirmation notification” to the television receiver 121 in step S403.

Then, the CPU 41 of the television receiver 121
Upon receiving the above “confirmation notification”, the infrared transmitter 417 notifies the remote controller 104 of the establishment of synchronization in step S404. As a result, synchronization between the BS tuner 102 and the television receiver 121 has been established.

FIG. 9 is a timing chart showing, in chronological order, how synchronization is established via a remote controller as a synchronization auxiliary device according to the present embodiment. As mentioned above, B
The S tuner 102 reads the count value in the time base unit 310 (timing t1 in FIG. 9), and sets the time base value (tuner time base 903 in FIG. 9) to
The infrared rays are transmitted to the remote controller 104 as a transmission medium.

At this time, the remote controller 104
By the time the time base value is received, a transmission delay due to space propagation or the like occurs, and the time base count is continued even during the transmission. An accurate time base value, that is, timing information serving as an operation reference on the tuner 102 side cannot be obtained.

Therefore, as shown in FIG.
4 receives the time base value from the BS tuner 102, the time corresponding to 3 counts here (m = 3)
910 is provided. Then, at a timing t2 after the elapse of the delay time, the remote controller 104
Loads the received time base count value into the time base unit 209.

Further, the remote controller 104 uses the time-base count value at which the counting was started by the above-mentioned timing t.
2, the time base value is read out from the time base unit 209, and the time base value is transmitted to the TV receiver 121, as in the case of transmission from the tuner to the remote controller. A delay 920 is provided.

Then, at timing t3 after the elapse of the delay time, the TV receiver 121 sets the remote control 104
, And a value obtained by adding a previously stored infrared transmission / reception delay value (here, 2 × m) to the count value is loaded into the time base unit 409.

As a result of these processes and calculations, as shown in FIG. 9, the time base 903 of the BS tuner 102 and T
The time base 905 of the V receiver 121 completely matches. That is, at time t3 in FIG. 9, both time bases are “n + 6”. Accordingly, the transmission frame 901 of the BS tuner 102 and the TV
The reception frame 906 of the receiver 121 is also synchronized, and the scramble timings 902 and 907 of the two completely match. This is the synchronization established state.

Here, the time base frequency is not related to the information rate or the communication frequency.

As described above, according to the present embodiment, first, the infrared remote control reads out the count value of the time base section in the BS tuner, stores it in the remote control, and then performs actual communication. It receives the radio transmission / reception channel (frequency) and scramble code to be used, and then transmits the received time base value and the like to the TV receiver. In this way, by using the infrared remote controller as a synchronization auxiliary device, incorporating a time base therein, and exchanging timing information between the BS tuner and the television receiver, the BS tuner and the television receiver are configured as follows. Even in the case of high-speed data communication, it is easy to establish initial synchronization, and both can operate on a common time axis, and it is necessary to incorporate a device for synchronization in the BS tuner and the television receiver Therefore, there is an effect that synchronization can be quickly established at low cost and synchronous communication can be performed.

When establishing synchronization between the BS tuner and the television receiver, a time base value is exchanged between the remote controller and the BS tuner which are involved in establishing synchronization, and
At each stage of exchanging the time base value between the remote control and the TV receiver, by performing calculations or the like in consideration of a predetermined infrared transmission / reception delay, the time bases of the BS tuner and the TV receiver can be completely matched, Even if the transmission rate increases (for example, a transmission rate exceeding megabits / second), strict timing adjustment can be performed, and mutual wireless communication can be performed in a state where synchronization is matched.

Further, even in a device where it is essential that initial synchronization is easy, by adopting the above-mentioned synchronization establishing method,
Since the restriction is eliminated, there is also an effect that a scheme in which initial synchronization is difficult, that is, a highly confidential communication scheme can be selected.

Further, when the synchronization establishing method according to the present embodiment is applied to a device having strict synchronization conditions (particularly, initial synchronization), for example, a radio device adopting the CDMA system,
The effect is remarkable, and a chip rate is given as time axis information between wireless devices adopting such a method, and phase adjustment by the above-mentioned synchronization establishment method, and cycle adjustment,
It is easy to see which position of the spreading code starts.

The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention. For example, the information transmission means (transmission medium) required for establishing synchronization is not limited to the above-mentioned infrared rays. As a medium therefor, a synchronization auxiliary device (not limited to a remote controller) and a communication device may be connected by a communication cable, or a method of inserting the synchronization auxiliary device into a predetermined slot may be adopted. In addition, a simple wireless communication (for example, Bluetooth, etc.)
May be adopted.

The radio transmission / reception channel and the scramble code are stored in a non-volatile memory such as a ROM in advance, and the BS tuner 102
From the side, or if the user
For example, a method such as setting by using a method may be used.

Further, in addition to the communication frequency and the scramble code, for example, the CDM
A so that parameters such as the spreading code of A can be set,
At the same time, the configuration may be such that synchronization timing information (spread code synchronization, symbol synchronization, frame synchronization) in wireless communication can also be set.

[0065]

As described above, according to the present invention,
A receiving means for receiving the time base read from the first communication device; a storage means for storing the received time base; and a transmitting means for transmitting the time base read from the storage means to the second communication device. Since the first communication device and the second communication device use the time base as the common synchronization timing information for wireless communication, even when performing high-speed data communication, the initial synchronization between the communication devices can be performed. Since the establishment is easy and there is no need to incorporate a device for synchronization in those devices, it is possible to quickly establish synchronization and perform synchronous communication at low cost.

According to another aspect of the invention, means for receiving a time base from the first communication device, means for storing the received time base, and means for transmitting the stored time base to the second communication device And a synchronization auxiliary device that uses the time base as common synchronization timing information between the first communication device and the second communication device is provided, so that quick synchronization establishment and synchronous communication between the communication devices are provided. Can be performed.

According to a further aspect, a step of receiving a time base from the first communication device, a step of storing the received time base, and a step of transmitting the stored time base to the second communication device are performed. A method for establishing synchronization between the first communication device and the second communication device using the time base as common synchronization timing information is provided. There is an effect that the synchronization can be quickly established at a low cost, and the initial synchronization can be easily established.

[Brief description of the drawings]

FIG. 1 is a diagram schematically showing how synchronization is established according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a bidirectional infrared remote controller according to the embodiment.

FIG. 3 is a block diagram showing an internal configuration of a wireless BS tuner according to the embodiment.

FIG. 4 is a block diagram showing a configuration of a television receiver according to an embodiment.

FIG. 5 is a schematic flowchart showing a flow until wireless communication is established between a BS tuner and a TV receiver.

FIG. 6 is a flowchart showing a detailed procedure of a remote control setting process according to the embodiment.

FIG. 7 is a flowchart showing a detailed procedure of a setting process of the TV receiver according to the embodiment.

FIG. 8 is a flowchart showing a procedure for confirming synchronization establishment according to the embodiment;

FIG. 9 is a timing chart showing, in chronological order, how synchronization is established via the remote controller according to the embodiment.

[Explanation of symbols]

100: building (user's home), 101: BS antenna, 1
02: BS tuner, 103, 122: antenna, 10
4: Bidirectional infrared remote controller, 105, 125: infrared transmitting / receiving unit, 106: antenna terminal A, 110: cable (coaxial cable), 121: television receiver, 202: key interface (I / F) unit, 206, 304 , 4
14. Central control unit (CPU), 207, 305, 415
... Read-only memory (ROM), 208, 306, 41
6: Write / read memory (RAM) as needed, 209, 31
0,409 ... time base part, 210,309,408
… Crystal oscillator circuit, 302… BS tuner section, 311, 4
10: frame timing generator, 312, 412: scramble code generator, 315, 406: baseband modulator, 317, 407: baseband demodulator, 40
2 TV receiver

Claims (15)

[Claims] 1. A communication system comprising a first communication device and a second communication device performing wireless communication with each other, a receiving unit receiving a time base read from the first communication device; Storage means for storing a base; and transmission means for transmitting a time base read from the storage means to the second communication device, wherein the first communication device and the second communication device use the time base A communication system, wherein the communication system is used for the wireless communication as common synchronization timing information. 2. The time base counting operation according to claim 1, further comprising: a first time required for receiving said time base by said receiving means, and a second time required for receiving said time base by said second communication device. 2. The communication system according to claim 1, further comprising: means for reflecting the information in the communication system. 3. An end point of the counting operation taking the first time and the second time into consideration is taken as a time-base coincidence point between the first communication device and the second communication device. The communication system according to claim 2, wherein: 4. The apparatus according to claim 1, further comprising means for providing a wireless communication parameter from said first communication device to a second communication device in addition to said time-base transmission / reception. Communications system. 5. The communication system according to claim 4, wherein said wireless communication parameters include at least a communication frequency, a spreading code, and a scrambling code. 6. The communication system according to claim 5, wherein light is used as a transmission medium of the time base and parameters for wireless communication. 7. The communication system according to claim 5, wherein a radio wave is used as a transmission medium of the time base and a parameter for wireless communication. 8. A synchronization auxiliary device used for a communication system including a first communication device and a second communication device that perform wireless communication with each other, wherein: a means for receiving a time base from the first communication device; Means for storing the stored time base, and means for transmitting the stored time base to the second communication device, wherein the time base is shared between the first communication device and the second communication device. A synchronization auxiliary device, which is synchronization timing information. 9. The apparatus according to claim 8, further comprising means for providing a parameter for wireless communication from the first communication device to a second communication device in addition to the time-base transmission / reception. Synchronization aid. 10. The synchronization assisting apparatus according to claim 9, wherein said wireless communication parameters include at least a communication frequency, a spreading code, and a scrambling code. 11. The optical communication device according to claim 9, wherein light is used as a transmission medium between the first communication device and the synchronization auxiliary device and between the synchronization auxiliary device and the second communication device.
Synchronization aid as described. 12. The synchronization assisting device according to claim 9, wherein a radio wave is used as a transmission medium between said first communication device and said synchronization assisting device and between said synchronization assisting device and said second communication device. apparatus. 13. A method for establishing synchronization in a communication system comprising a first communication device and a second communication device performing wireless communication with each other, comprising: receiving a time base from the first communication device; Storing the received time base; and transmitting the stored time base to the second communication device, wherein the first communication device and the second communication device share the time base. Synchronization establishment method characterized by establishing mutual synchronization by using as synchronization timing information. 14. The method according to claim 13, further comprising the step of providing wireless communication parameters from the first communication device to the second communication device in association with the time-base transmission / reception. Synchronization establishment method. 15. The method according to claim 15, further comprising: a first time required for receiving the time base in the receiving step;
14. The synchronization establishing method according to claim 13, further comprising a step of reflecting a second time required for the communication device to receive the time base in the time base counting operation.