JP2003078471A - Erroneous synchronization prevention algorithm and radio communication equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To establish synchronization in a short period of time without generating erroneous synchronization in radio communication equipment using a TDD communication method. SOLUTION: A master side communication machine transmits a signal to a slave side communication machine by alternately adding a correct signal and a dummy signal to control data of a synchronization request signal, in each frame, to be transmitted from the master side communication machine to the slave side communication machine. If the slave side detects a dummy SYNC signal in the first frame, the slave side adds a synchronizing signal counter, if the slave side can not detect synchronizing signal data in the next frame, the slave side subtracts a count value (CT), and since the slave side decides that synchronization is established if the slave side subsequently and continuously detects synchronizing signal data, the slave side eliminates the influence of the dummy SYNC signal and establishes synchronization in a short period of time without generating erroneous synchronization.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention uses a time division transmission / reception communication system (hereinafter referred to as TDD communication system) to establish a synchronization establishment algorithm for a TDD wireless communication device composed of a transmitter and a receiver which can be wirelessly connected to each other. And a wireless communication device.

[0002]

2. Description of the Related Art In recent years, wireless communication devices using the TDD communication system have rapidly spread, and have spread widely as general household products such as cordless telephones.

The TDD communication system is Time Division Dupl
ex is a method in which the master-side communication device 1 and the slave-side communication device 2 communicate with each other by repeatedly receiving and transmitting the same frequency in a short time as shown in FIG. 3, and a conceptual diagram thereof is shown in FIG. .

In this communication system, there is a minimum unit of transmission and reception called a frame, and the unit frame has a data format as shown by 3 in the figure, and its structure is P, DCH, and BCH. , SYNC, and M. P is located at the beginning of the format and is a channel region for stabilizing data modulation / demodulation.
It is also used to recognize the beginning of data. DCH
Is a channel region used for transmitting / receiving channel control data, BCH is a channel region used for transmitting / receiving voice data, M is a channel region arranged at the end of the format and used for recognizing the end of data. is there.

Communication can be established by alternately transmitting and receiving these frames, and voice communication can be performed by transmitting and receiving voice data. Note that TX indicates a frame of the transmission channel, and RX indicates a frame of the reception channel. The signal (TX) transmitted from the master side communication device is received as RX in the slave side communication device, and conversely, the signal (T) transmitted from the slave side communication device.
X) is received as RX at the master communication device. Next, a general synchronization establishment method will be described.

The data format used when establishing synchronization is
Voice data area (BC
H) is added to the channel area of DCH for data for channel control, the area of data for channel control is increased, and the data transfer amount is increased, and the data format shown in 4 of FIG. 5 is used (hereinafter, referred to as data mode data format. ) Is common.

The master side communication device transmits a signal in the data mode data format as shown in FIG. The slave side communication device is the SYNC of the master side transmission signal.
Search in continuous receive mode until you find the signal. At this time,
CT (the number of SYNC signal receptions) is set to 0 until the SYNC signal sent from the master communication device is received.

When the SYNC signal is received for the first time, CT becomes 1, the receiving operation of the receiver is once turned off (the power supply of the receiving circuit is turned off), and the frame is received again immediately after one frame from the time of receiving the first SYNC signal. The receiving operation on the machine side is started and it is confirmed whether or not there is the same SYNC signal as the first time. If there is a SYNC signal, CT becomes 2, the receiving operation of the receiver is turned off again, and if the same SYNC signal can be confirmed one frame later, CT becomes 3 and synchronization is established. If the SYNC signal cannot be confirmed at the second and third times, the CT value is reduced by 1, and if CT becomes 0, continuous reception is performed, and if 1 then it is confirmed whether or not there is a SYNC signal after the next one frame (Fig. 5 (b) (c)).

In order to establish synchronization in this way, in order to prevent erroneous synchronization, it is generally established by checking the SYNC signal several times (in this description, synchronization is established when CT = 3).

Next, an erroneous synchronization occurrence mechanism will be described. In order to establish synchronization, the master side communication device transmits a signal to the slave side communication device using the data mode data format. At that time, the DCH channel control data usually includes a signal for establishing synchronization. Specifically, there are communication request data (hereinafter, link request data), channel information, an ID for identifying each communication device, and the like.

Further, the channel control data is scrambled in a predetermined pattern to improve confidentiality so that it cannot be intercepted by a third party communication device.

At this time, as shown in FIG. 6, if the data for channel control in the DCH happens to have the same data as the SYNC signal (hereinafter, referred to as "false SYNC signal"),
In response to the false SYNC signal, the slave side communication device erroneously starts the operation of establishing synchronization. Specifically, in the slave communication device that is in the continuous reception mode for establishing synchronization, the SYN in the DCH of the RX data to be received is
If there is a false SYNC signal that is the same data as the C signal, it is recognized as a SYNC signal and CT becomes 1,
Turn off the receiving operation of the receiver once, and then perform the first SYNC
The reception operation of the receiver is started again immediately before one frame after the reception of the signal, and it is confirmed whether or not there is the same SYNC signal as the first time. Also in this case, if there is a similar false SYNC signal, it is confirmed whether or not there is a SYNC signal in the next frame. If there is also a false SYNC signal at this time, the master side and the slave side are Then, the synchronous operation is started (when the synchronous operation is started by receiving the SYNC signal three times). However, it is correct SY
Since it is not the synchronization by the NC signal, the data for channel control of the DCH cannot be exchanged, and as a result, the communication cannot be established, and the synchronization has to be performed again.

In order to prevent such false synchronization, DC
Channel control data in H happens to be SYNC
It is possible to control the data in the channel control data DCH, such as by eliminating the data that may be erroneously synchronized so that it does not become the same signal as the signal, but software control is required, Control becomes complicated. When erroneous synchronization actually occurred, an error occurred in various data exchanges thereafter, and it was attempted to detect the erroneous synchronization and establish synchronization again.

[0014]

The conventional synchronization establishing means using the TDD communication system as described above has a possibility of erroneous synchronization and synchronization delay.

In view of the above-mentioned conventional problems, it is an object of the present invention to realize a mechanism for preventing erroneous synchronization even if arbitrary data is used and establishing synchronization in a short time.

[0016]

SUMMARY OF THE INVENTION To solve this problem, the present invention provides continuous channel control data when synchronization is established in a wireless communication device using a time division transmission / reception communication system (hereinafter referred to as TDD communication system). This is an erroneous synchronization prevention algorithm in which dummy data is alternately transmitted without being transmitted.

According to the present invention, it is possible to prevent erroneous synchronization and establish synchronization in a short time.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION According to the first aspect of the present invention, in a wireless communication device using a TDD communication system, a master side communication device transmits to a slave side communication device.
This is an erroneous synchronization prevention algorithm in which a correct signal and a dummy signal are alternately added to the channel control data DCH of the synchronization request signal for each frame and the signal is transmitted. This enables synchronization in a short time without causing erroneous synchronization. Has an action characterized by establishing

According to a third aspect of the present invention, when the same data as the synchronization signal data is accidentally present in the channel control data, the slave side communication device determines that the synchronization signal exists in the channel control data of the first frame. When the same data as the data (false SYNC signal) is detected, the count value (CT) of the sync signal counter is added to check whether sync signal data exists in the next frame, and if sync signal data cannot be detected in the next frame Is a false synchronization prevention algorithm that determines that synchronization is established when the count value (CT) of the synchronization signal counter is subtracted and synchronization signal data is continuously detected in the subsequent frames. Control Data-By detecting the false sync signal in DCH, the sync signal counter Even if the count value (CT) is added, the dummy data is sent in the next frame, so the sync signal data is not detected. The count value (CT) of the sync signal counter is subtracted to return it to the false value. The influence of the SYNC signal can be eliminated.

The invention according to claim 4 of the present invention is the TDD.
A wireless communication device of a communication system, wherein a transmission data generation unit that generates transmission data by synthesizing dummy data that is transmitted at a transmission timing of a synchronization signal and that has data content that does not match the synchronization signal, and the transmission data And a radio unit that generates and outputs a radio signal for transmission by converting the radio signal, and transmits the synchronization signal data and the dummy data alternately at the synchronization signal transmission timing of the radio signal. , And has the action of establishing synchronization in a short time without causing erroneous synchronization.

FIG. 1 shows an embodiment of the present invention.
2 and FIG.

(Embodiment 1) FIG. 1 is a block diagram of a master side communication device in Embodiment 1 of the present invention.
In FIG. 1, reference numeral 100 is an antenna for transmitting and receiving radio signals, 101 is a radio for demodulating and outputting received data from an input radio signal, and for converting input transmission data to generate and outputting a radio signal for transmission. It is a department. Reference numeral 102 denotes a synchronization signal (SYN) of the reception data demodulated by the wireless unit 101.
It is a SYNC signal detector for detecting the C signal).

Reference numeral 103 denotes a transmission data generation unit for synthesizing dummy data which is transmitted at the transmission timing of the SYNC signal and has dummy data having a data content that does not match the SYNC signal, and 104 is reproduced from the demodulated reception data. A speaker that outputs an audio signal, a microphone 105 that inputs an audio signal for transmission, and a control unit 106 that controls the entire apparatus.

When operating as a master communication device, the control unit 106 controls the synchronization signal data and the transmission data generation unit 10.
The dummy data from 3 are alternately transmitted at the synchronization signal transmission timing of the wireless signal.

The main hardware configuration of the slave side communication device, which is the communication partner of the master side communication device, is the same as in the block diagram shown in FIG. However, the control unit 106 controls the SYNC
A synchronization signal counter 107 that counts up each time a signal is detected is provided. The synchronization signal counter 107 is
The count value (CT) is added by detecting the same data (false SYNC signal) as the normal SYNC signal or the accidentally generated SYNC signal, and subtracted when the synchronization signal data cannot be detected.

FIG. 2 is a conceptual diagram of synchronization establishment according to the present invention, in which the master side communication device uses the data mode data format and alternately sends correct data and dummy data on the channel control data DCH and sends them out.

Here, the dummy data is the data of the SYNC signal (for example, "111011101110111").
Data that does not match 0 ") and is fixedly determined in advance (for example, continuous 80 bits of 0). In addition, when scrambling the DCH to enhance confidentiality, the scrambled data is naturally used. Is fixedly determined so that it does not match the SYNC signal.The dummy data is stored in the storage unit in advance, extracted when necessary, and transmitted.

Below, D is transmitted from the master side transmitter thus configured and transmitted from the transmitting circuit (not shown).
SYNC in the channel control data of CH
The operation when the same data as the signal exists is (1)
The slave side communication device that receives one of the same data as the SYNC signal in the channel control data and the other (2) accidentally has a plurality of data in the channel control data The operation of will be described below.

(1) The operation when the same data as the SYNC signal (false SYNC signal) is accidentally present in the channel control data is as follows.

The slave side communication device uses the fake SYNC in the channel control data-DCH of the first frame.
The signal is detected, the synchronization signal counter 107 is added, and C is added.
Set T = 1, turn off the receiver once, and set S in the next frame.
Check to see if there is a YNC signal.

However, since the master side communication device uses the dummy data for the channel control data DCH in the next frame, the dummy data is sent to the slave side communication device. Therefore, in the slave side communication device, SYNC
No signal can be detected, and CT is returned to 0. Then, it shifts to the continuous reception mode again, and again within the same frame, a new SYNC.
When a signal is detected, CT = 1. Then, the receiver is turned off once and it is checked whether or not there is a SYNC signal in the next frame. At this time, if the SYNC signal can be confirmed again, CT = 2 is set, and S is set in the next frame.
The YNC signal can be confirmed, CT = 3, and synchronization is correctly established.

(2) The operation when the same data as the SYNC signal exists by chance in the channel control data DHC is as follows. That is, the SYNC signal is detected in the first frame, but since there is no SYNC signal in the next frame, the synchronization can be correctly established by the same procedure as in the case of (1).

[0033]

As is apparent from the above description, the false synchronization prevention algorithm of the present invention is a wireless communication device using the TDD communication system, in which a master side communication device sends a synchronization request to a slave side communication device. By sending the signal by alternately adding the correct signal and the dummy signal to the control data of the signal for each frame, it is possible to obtain the advantageous effect of establishing the synchronization in a short time without causing erroneous synchronization.

[Brief description of drawings]

FIG. 1 is a block diagram of a master communication device according to a first embodiment of the present invention.

FIG. 2 is a conceptual diagram of a synchronization establishing procedure according to the present invention.

FIG. 3 is a conceptual diagram of a wireless device using a TDD communication method.

FIG. 4 is a conceptual diagram of a normal communication state of the TDD communication method.

FIG. 5 is a conceptual diagram of a TDD communication system synchronization establishment procedure.

FIG. 6 is a conceptual diagram of occurrence of false synchronization in the TDD communication method.

[Explanation of symbols]

1 Master side communication device 2 Slave side communication device 3 Standard data format of TDD communication system 4 TDD communication system data mode data format 100 antenna 101 wireless unit 102 SYNC signal detector 103 transmission data generation unit 104 speakers 105 microphone 106 control unit

Continued front page    F term (reference) 5K028 AA15 BB04 DD01 DD02 MM12                       MM16 NN01 RR04                 5K047 AA02 AA12 BB01 BB05 HH01                       HH55 HH59 LL15 MM02 MM11                       MM24 MM56                 5K067 AA33 CC04 DD25 EE02 EE10                       EE71 HH21

Claims (6)

[Claims] 1. In a wireless communication device of a time division transmission / reception communication system, a correct signal and a dummy signal are alternately added frame by frame to control data of a synchronization request signal transmitted from a master side communication device to a slave side communication device. A false synchronization prevention algorithm characterized by transmitting a signal. 2. In a time division transmission / reception communication type wireless communication device, a correct signal and a dummy signal are alternately added to each frame of control data of a synchronization request signal transmitted from a master side communication device to a slave side communication device. When the slave communication device detects the same data as the synchronization signal data in the channel control data of the first frame, it adds the count value of the synchronization signal counter, and if the synchronization signal data cannot be detected, Is an erroneous synchronization preventing algorithm, wherein the count value of the synchronization signal counter is subtracted, and thereafter, when synchronization signal data is detected a predetermined number of times in succession, it is determined that synchronization has been established. 3. A wireless communication device for performing communication between a master-side communication device and a slave-side communication device in a time-division transmission / reception communication method, wherein the slave-side communication device accidentally uses the same data as the synchronization signal data as channel control data. If the same data as the sync signal data in the channel control data of the first frame is detected, the count value of the sync signal counter is added, and it is confirmed whether there is sync signal data in the next frame. When the sync signal data cannot be detected in the frame of 1, the count value of the sync signal counter is subtracted, and when the sync signal data is continuously detected in the subsequent frames, it is determined that the synchronization is established. False synchronization prevention algorithm. 4. A wireless communication device of a time division transmission / reception communication system, wherein transmission is performed at a transmission timing of a synchronization signal, and dummy data having a data content that does not match the synchronization signal is combined to generate transmission data. A data generation unit and a wireless unit that converts the transmission data to generate and output a wireless signal for transmission and outputs the synchronization signal data and the dummy data alternately at the synchronization signal transmission timing of the wireless signal. A characteristic wireless communication device. 5. In a wireless communication device for performing communication by a time division transmission / reception communication system between a master side communication device and a slave side communication device, the master side communication device demodulates received data from a wireless signal input from an antenna. A wireless unit for outputting and outputting the input and output transmission data to generate and outputting a wireless signal for transmission, and a synchronization signal detection unit for detecting the synchronization signal data in the reception data demodulated by the wireless unit. And a transmission data generation unit that synthesizes dummy data having data content that does not match the synchronization signal and transmits at the transmission timing of the synchronization signal data, and a speaker that outputs an audio signal reproduced from the demodulated reception data. , A microphone for inputting a voice signal for transmission, and a control unit for alternately putting correct data and dummy data on the channel control data. Slave communication apparatus adds each time it detects a sync signal data, a radio communication apparatus characterized by comprising a synchronous signal counter for subtraction if it can not detect the synchronization signal data. 6. The wireless communication device according to claim 5, wherein the dummy data is data fixedly determined in advance so as not to match the synchronization signal data and stored in the storage unit in advance.