JPH0936794A - Spread spectrum communication relay system - Google Patents

Abstract

(57) [Abstract] [PROBLEMS] To enable direct-spread-spectrum spread spectrum communication with the same transmission frequency on the transmission side and retransmission frequency on the relay side. A transmission device 1 has a switching circuit 1e on the transmission side,
Send data in frame units. After the transmission of one frame is completed, the mode is switched to the receiving side, and the retransmitted signal from the relay device 2 is on standby. The relay device has the switching circuit 2e on the receiving side,
A transmission signal from the transmission device is received and data for one frame is demodulated. A second relay processing control signal is added to the demodulated signal. After that, the switching circuit is set to the transmission side, and one frame of data is retransmitted at the same frequency as the transmission frequency.
After this re-transmission, it switches to the receiving side and waits for the next frame from the transmitting device. The receiving device 3 extracts data from the retransmitted signal by the data extracting unit 3c or the like. The transmission device side in the standby state transmits the next frame after detecting the second relay processing control signal from the retransmission signal (detection unit 1d).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a direct sequence spread spectrum communication relay system.

[0002]

2. Description of the Related Art In wireless communication, if the distance between two points is long and direct communication is impossible due to the transmission power, it is necessary to install a relay device between them. In the conventional relay method in wireless communication, for example, as shown in FIG. 3, the transmission frequency F1 emitted from the transmitter 11 and the retransmission frequency F2 emitted from the relay 12 to the receiver 13 which is the final destination are different. Is done by.

[0003]

However, when the communication system is the spread spectrum system, the transmission speed of information is proportional to the spread frequency bandwidth, so that high speed communication is performed by the conventional method (FIG. 3). Then, the frequency band used by the entire relay system becomes very wide. Therefore, since the available frequency band is also limited, the transmission frequency F1 and the retransmission frequency as shown in Fig. 3 are used in the spread spectrum communication.
Relaying F2 with a different frequency is not a good idea. The present invention has been made from such a background, and in the case of performing communication by a direct spread spectrum spread spectrum method, the transmission frequency from the transmitter and the retransmission frequency from the relay are performed at the same frequency. The purpose of the present invention is to provide a relay system.

[0004]

SUMMARY OF THE INVENTION The present invention divides data to be transmitted, adds a first relay processing control signal and a required signal to the divided data, and relays a framed signal by a spread spectrum signal. Transmission to the device, reception and demodulation of the signal retransmitted from the relay device, transmission means for switching between the transmission and reception in frame units, and reception and demodulation of the transmission signal by the transmission means A second relay processing control signal and a required signal are added to the demodulated framed signal, and the newly framed signal is retransmitted to a receiving device and the transmitting means by a spread spectrum modulation signal, The transmitting means and the relay means alternately switch between transmitting and receiving, respectively. Transmission, detecting the end of the retransmission process by the relay unit, there is provided a spread spectrum communication relay system adapted to transmit a detection signal.

[0005]

In the transmitting device, the switching circuit is set to the transmitting side at the time of transmission, and the data is transmitted by the spread spectrum signal by the direct spread method in frame units. When the transmission of one frame is completed, the switching circuit is switched to the receiving side, and the standby state for receiving the retransmission signal from the relay device is set. The relay device has a switching circuit on the reception side, receives a transmission signal from the transmission device, and demodulates data for one frame. A second relay processing control signal is added to the demodulated signal in place of the first relay processing control signal added on the transmission side. After this processing,
The switching circuit is switched to the transmission side, and the data for one frame to which the new second relay processing control signal is added is re-generated by the spread spectrum signal by the direct spread method using the carrier having the same frequency as the transmission frequency from the transmitter. Send. After this re-transmission, the switching circuit is switched to the receiving side, and the receiving state of the next frame from the transmitting device is set.

The retransmitted signal emitted from the relay device is received by the receiver, which is the final destination of data transmission, and the transmitter. The receiving device receives and demodulates this retransmitted signal,
The target data is extracted by the data extraction unit. As a result, one frame of data has been transmitted.
On the other hand, the transmitting device side in the standby state for receiving the retransmitted signal from the relay device receives the second signal and adds the second signal added by the relay device side.
The relay processing control signal of is demodulated. When this second relay processing control signal is detected (detection unit), it is confirmed that the relay device has retransmitted. After detecting this control signal, the next frame is transmitted. Hereinafter, this frame-by-frame transmission is repeated.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A spread spectrum communication relay system according to the present invention will be described below with reference to the drawings. 1 is a block diagram of essential parts showing an embodiment of a spread spectrum communication relay system according to the present invention, and FIG. 2 is an example of a framed data structure for explaining FIG. In FIG. 1, 1
Is a transmitting device, 2 is a relay device, and 3 is a receiving device. In the transmitter 1, 1a is an antenna for both transmission and reception, and 1b
Is a modulation / transmission unit for transmitting the framed signal to the relay device 2 by the spread spectrum modulation signal, and 1c is a second signal added to the retransmitted signal at the relay device side by receiving the signal retransmitted from the relay device. Receiving / demodulating section for demodulating the relay processing control signal, 1d, a detecting section for detecting the demodulated second relay processing control signal, 1e, a switching circuit for switching between a transmitting state and a receiving state, 1f, a frame of the transmitting signal When the transmission is completed, the switching circuit 1e is switched to the transmission side to perform transmission of one frame, and when the transmission is completed, the switching side is switched to the reception side. Is a transmission control unit that controls the switching of the switching circuit so that the next frame is transmitted by switching to.

Next, in the relay device 2, 2a is an antenna for both reception and transmission, 2b is a reception / demodulation unit for receiving a transmission signal from the transmission device 1 and demodulating a framed signal, and 2c is demodulation. The second relay processing control signal is added to the framed signal, and the newly framed signal is spread-spectrum modulated to form the receiving device 3 and the transmitting device 1.
A modulation / transmission unit for re-transmitting to, a detection unit for detecting the first relay processing control signal from the demodulated framed signal, 2e for a switching circuit for switching between a transmission state and a reception state,
2f changes to a new frame and switches the switching circuit 2d to the receiving side when receiving to receive a 1-frame signal, switches to the transmitting side when the same reception is completed, and receives again when the same transmission is completed. It is a relay control unit that performs switching control of the switching circuit 2d so as to switch to the side and receive the next frame. Next, in the receiving device 3,
3a is a receiving antenna, 3b is a receiving / demodulating unit that receives a retransmitted signal from the relay device 2 and demodulates a framed signal, and 3c is a data extracting unit that extracts data related to transmission from the demodulated signal. is there.

Next, the operation of the present invention will be described. The essence of the present invention is to frame data and transmit it by time division. This frame is constructed, for example, as shown in FIG. As shown in the figure, D1 is an AGC control signal, and if the receiving side has an AGC circuit, the same AG
It is for securing the period until C control stabilizes,
D2 is a diversity control signal, and when the receiving side operates the antenna diversity, it is for securing a period during which the operation is performed, D3 is a frame synchronization signal for synchronizing each frame, and D4 is A relay processing control signal for specifying the transmission device or relay device of the other party for signal transmission / reception, D5 is a part of main data for transmission, D6
Is a frame end determination signal for determining that one frame worth of data has ended. Incidentally, in each of the above signals,
D1 to D4 are generally called a preamble, and D6 is called a postamble.

In the relay processing control signal D4, the transmitter 1 side adds the first relay processing control signal to this position, and the relay apparatus 2 side replaces the first relay processing control signal with the second relay processing control signal. A relay processing control signal is added. At the beginning of transmission, the switching circuit 1e of the transmission device 1 is set to the transmission side (a side) by the transmission control unit 1f and puts it in the transmission state. Same transmission control unit
In 1f, the input transmission main data is divided into a required number of pieces of data, and each of the above-mentioned data is added to the divided data to form a frame. With this framed signal as one unit,
Direct spread spectrum transmission using a carrier wave of the required frequency. Therefore, the signal framed by the transmission control unit 1f is sent to the modulation / transmission unit 1b, and QP
Required processing such as information modulation such as SK or FSK, spread spectrum modulation using a PN code, conversion to a required RF frequency, etc. is performed and the result is transmitted from the antenna 1a to the relay device 2. When this transmission is completed, the transmission control unit 1f switches the switching circuit 1e to the receiving side (b side) and puts it in a standby state for receiving a retransmission signal from the relay device 2 described below.

At the beginning of transmission, the relay device 2 has a relay controller 2f.
Is set to the receiving side (a side), and a signal reception standby state from the transmitting device 1 is set. As a result, the transmission signal from the transmission device 1 is received. The received signal is received
The signal is sent to the demodulation unit 2b, and the framed signal is demodulated therein. From this demodulated signal, the transmitter 1 is detected by the detector 2d.
The first relay processing control signal added on the side is detected, and it is confirmed that the relay device 2 is a target normal transmission signal. Further, in this case, the demodulated signal is the relay control unit 2f.
Is temporarily stored in the memory function (memory unit 21), which is one of the functions. If this is detected, the relay controller 2f will detect the memory
The frame signal is read from 21, and the first relay processing control signal in the signal is replaced with the second relay processing control signal indicating the relay device 2. In this case, other signal components such as frame synchronization and data remain unchanged.

By exchanging the relay processing control signals,
A new framed signal is constructed. In this way, the new framed signal generated by the relay control unit 2f is sent to the modulation transmission unit 2c, and similarly to the transmission device 1, information modulation and spread spectrum modulation are performed. In addition, at this stage, the relay control unit 2f switches the switching circuit 2e to the transmission side (b side).
As a result, the framed signal is retransmitted from the antenna 2a as a spread spectrum signal. The carrier frequency in this case is the same as the transmission frequency. After this retransmission, the relay control unit 2f switches the switching circuit 2e to the receiving side (a side) again, and puts it in a standby state for receiving the next frame signal transmitted from the transmitter 1.

The signal retransmitted from the relay device 2 is received by the receiving device 3 which is the final data transmission destination and the transmitting device 1. In the receiving device 3 which is one receiving destination, the signal received by the antenna 3a is received and demodulated by the receiving / demodulating unit 3b. This demodulated signal has the configuration shown in FIG. 2 described above, and in addition to the main data (D5), another signal component (D
1, D2, etc.) are included. Therefore, the data extraction unit 3c extracts the data (D5) that is the object of transmission. As a result, the first frame data is obtained. After that, a standby state for receiving the next frame data is entered. In the transmitter 1 which is the other receiver, as described above, the switching circuit
1e is on the receiving side (b side). Therefore, the signal received by the antenna 1a is received and demodulated by the reception / demodulation unit 1c. The demodulated signal includes the second relay processing control signal added by the relay device 2. The detection unit 1d detects the second relay processing control signal from this demodulated signal.

Based on this detection, the transmission control unit 1f confirms that the relay device 2 has retransmitted. When this confirmation is made,
The transmission control unit 1f switches the switching circuit 1e to the transmission side (a side) again, while transmitting the next framed signal in the same procedure as described above. After the end of the transmission, the transmission control unit 1f changes the switching circuit 1e.
Is set to the receiving side (b side), and the standby state is set. The transmitter 1 then repeats this process. Even in the relay device 2,
The next frame is received and processed as before. Hereinafter, this is repeated. Further, the receiving device 3 also extracts data from the frame data that is sequentially transmitted. As mentioned above, the same carrier frequency is used for both transmission and retransmission,
Required data is relayed in frame units.

[0015]

As described above, according to the present invention, in the case of communicating between long distance two points by a direct spread spectrum communication method via a relay device, data is framed and one framed frame is used. Since the transmission method is that the signal is transmitted to the relay device, and the relay device transmits the next frame after the retransmission of the signal is completed, the transmission frequency from the transmission device and the retransmission frequency from the relay device are Communication with the same frequency becomes possible. This prevents the frequency band from expanding and enables high-speed communication. As described above, by using the present invention, it is possible to extend the communication distance by the spread spectrum method by direct spread without reducing the transmission speed.

[Brief description of drawings]

FIG. 1 is a block diagram of essential parts showing an embodiment of a spread spectrum communication relay system according to the present invention.

2 is a framed data configuration diagram for explaining FIG. 1; FIG.

FIG. 3 is a principal block diagram showing an example of a conventional relay system.

[Explanation of symbols]

 1 transmitter 1a antenna 1b modulation / transmission unit 1c reception / demodulation unit 1d detection unit 1e switching circuit 1f transmission control unit 2 relay device 2a antenna 2b reception / demodulation unit 2c modulation / transmission unit 2d detection unit 2e switching circuit 2f relay control unit 3 Receiver 3a Receiver antenna 3b Receiver / demodulator 3c Data extractor

Claims (8)

[Claims] 1. Dividing main data to be transmitted, adding a first relay processing control signal and a required signal to the divided data, and transmitting a framed signal to a relay device by a spread spectrum signal; Receiving and demodulating the signal retransmitted by the relay device, transmitting means for switching between transmitting and receiving in frame units, receiving and demodulating the transmitting signal by the transmitting means, and demodulating the framing The second relay processing control signal and the required signal are added to the generated signal, and a new framed signal is retransmitted to the receiving device and the transmitting means by a spread spectrum modulation signal, and the transmission is performed in frame units. It comprises a relay means for switching between reception and transmission, and alternately switches between transmission and reception of the transmission means and the relay means, and the transmission by the transmission means is transferred to the relay means. A spread spectrum communication relay system characterized by detecting the end of the retransmission processing by and transmitting by the detection signal. 2. A modulator / transmitter for transmitting the framed signal to a relay device by a spread spectrum modulation signal, and a signal retransmitted from the relay device, the transmitter means, on the relay device side. Second added to retransmitted signal
A receiver / demodulator that demodulates the relay processing control signal, and a detector that detects the demodulated second relay processing control signal,
A switching circuit for switching between a transmission state and a reception state, the framing, and the switching circuit is switched to the transmission side at the time of transmission to perform transmission of one frame, and when the transmission is completed, it is switched to the reception side. 7. A transmission control unit for performing switching control of the switching circuit so that when the relay processing control signal is detected by the detection unit, it is switched to the transmission side again and the next frame is transmitted. 1. The spread spectrum communication relay system described in 1. 3. A reception / demodulation unit for receiving the transmission signal from the transmission unit and demodulating the framed signal by the relay unit, and a second relay processing control for the demodulated framed signal. A modulation / transmission unit that retransmits a signal to which a new frame is added with a signal by a spread spectrum modulation signal to the receiving device and the transmission unit, and a first relay processing control signal from the demodulated framed signal Detection unit, a switching circuit for switching between a transmission state and a reception state, the new framing, and the switching circuit is switched to the receiving side at the time of reception to receive a signal of one frame, and the same reception is performed. When the transmission is completed, the switching circuit is switched to the transmitting side, and when the transmission is completed, the switching circuit is switched to the receiving side again to receive the next frame. 2. The spread spectrum communication relay system according to claim 1, wherein the spread spectrum communication relay system comprises: 4. A receiving device for receiving the retransmitted signal by the relay means, the receiving device receiving the retransmitted signal by the relay means,
A receiving / demodulating unit that demodulates the framed signal,
The spread spectrum communication relay system according to claim 1, wherein the spread spectrum communication relay system comprises a data extraction unit that extracts data related to transmission from the demodulated signal. 5. The spread spectrum modulated signal is PN
The spread spectrum communication relay system according to claim 1, 2 or 3, wherein the signal is a direct spread signal using a code or the like. 6. The spread spectrum communication relay system according to claim 1, wherein the carrier frequency related to the transmission in said transmitting means and the carrier frequency related to the retransmission in said relay means are the same frequency. 7. An AGC control signal having a required number of bits for each of the framed signals in the transmitting means,
A diversity control signal added after the same AGC control signal, a frame synchronization signal added after the same diversity control signal, a first relay processing control signal added after the same frame synchronization signal, and the same control The spread spectrum communication relay system according to claim 1 or 2, wherein the spread spectrum communication relay system comprises main data relating to divided transmission added after the signal and a frame end determination signal added after the main data. 8. The framed signal in the relay means is formed by replacing the first relay processing control signal of the framed signal from the transmitting means with the second relay processing control signal. The spread spectrum communication relay system according to claim 1 or claim 3 characterized in that.