JP2001308777A - Communication system and power consumption saving method used for the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize the reduction of power consumption in a waiting time and a capable of preventing the occurrence of incorrect synchronization in the communication system. SOLUTION: A controlling station 1 receives calling information from a calling station 2 through an incoming control line #1, then performs all call of line numbers (#2, #3) and time entries assigned to lines of contact of the calling station 2 and an incoming call station 3 to an outgoing control line #0. The calling station 2 and the incoming call station 3 receive the outgoing control line #0, detect the line number, then assign the line number of a transmitting part 32 and a receiving part 36 based on a detection result. When the calling station 2 and the incoming call station 3 to which the line number is assigned receive a line setting flag from a line control part, the transmitting sends out talk data to the speech lines #2 and #3 based on a request to send and a time entry. Besides, the receiving part starts initial synchronization processing in a initial synchronizing circuit based on the control signal of an electric power control part obtained from the time entry for the reception set up of speech lines #2 and #3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication system and a power saving method used for the communication system, and more particularly to a satellite communication system using a spread spectrum system.

[0002]

2. Description of the Related Art Conventionally, in a communication system using a spread spectrum system, as shown in FIG.
The calling station 5 includes a calling station 5 and a called station 6.
And the called station 6 are connected by a connection procedure as shown in FIG.

Here, the transmitting section of the calling station 5 is shown in FIG.
As shown in (a), a modulator 43 is provided. When a transmission request is input from a terminal 41 connected to the calling station 5, the modulator 43 transmits a synchronization signal and then converts the synchronization signal into call data from the terminal 41. On the other hand, modulation is performed based on the spreading code generated from spreading code generator 44 in accordance with the setting of the line number (# 2), and the signal is transmitted to communication line # 2.

The receiving unit of the calling station 5 is shown in FIG.
As shown in FIG. 7, a demodulator 47 and an initial synchronization circuit 48 are provided. The demodulator 47 demodulates a signal from the communication line # 3 based on the synchronization control in the initial synchronization circuit 48, and generates communication data. The data is transmitted to the terminal 45 connected to the station 5.

At this time, the demodulator 47 performs demodulation based on the spreading code generated from the spreading code generator 50 in accordance with the setting of the line number (# 3). The initial synchronization circuit 48 performs synchronization control according to the power control from the power control unit 49 when the line setting flag is turned on. Although not shown, the called station 6 has the same configuration as the calling station 5, and performs the same operation as the calling station 5.

The operation of the conventional communication system will be described with reference to FIGS. First, the control station 4 having received a call from the calling station 5 via the uplink control line # 1 assigns the line numbers (# 2, # 2) assigned to the downlink control line # 0 to the calling lines of the calling station 5 and the called station 6. Broadcast # 3). Calling station 5
When the receiving station 6 receives the downlink control line # 0 and detects the line number, it allocates the line numbers of the transmitting unit 42 and the receiving unit 46.

[0007] The calling station 5 and the called station 6 to which the line numbers are assigned receive line setting flags from a line control unit (not shown), and the transmitting unit 42 transmits the communication lines # 2 and # based on the transmission request.
3 and the call data is transmitted.

[0008] The initial synchronization circuit 48 of the receiving unit 46 controls the power of a power control unit 49 that performs power control based on the line setting flag from the line control unit in preparation for reception (standby) of the communication lines # 2 and # 3. The initial synchronization process is started based on After the initial synchronization is established by the initial synchronization circuit 48, a call between the calling station 5 and the called station 6 starts. If synchronization is lost after the start of the call between the calling station 5 and the called station 6, resynchronization is performed.

[0009]

However, in the conventional communication system, the number of flip-flops corresponding to the number of chips of the spreading code is determined by the initial synchronization circuit of the receiving unit in order to detect the coincidence of the line number (spreading code). Since an integrated matched filter is used, in the case of a telephone line, FIG.
As shown in FIG. 1, there is a problem that the power consumption of the receiving unit that performs the initial synchronization processing increases. Further, in the case where the synchronization processing is performed during a period when there is no input signal, the occurrence of erroneous synchronization due to noise or a multiplex signal also becomes a problem.

Therefore, an object of the present invention is to solve the above-mentioned problems, to reduce the power consumption during the standby time, and to prevent the occurrence of erroneous synchronization, and a power consumption saving method used therefor. Is to provide.

[0011]

In a communication system according to the present invention, when a call from a calling station to a called station via an uplink control line is accepted, the control station connects the calling station and the calling station to a downlink control line. Simultaneously broadcast a line number to be assigned to the call line of the called station, and based on the line number at the calling station and the called station,
A communication system for performing a call between the calling station and the called station after establishing initial synchronization for preparation of reception of the communication line, wherein the communication between the calling station and the called station is performed via an uplink control line. The control station includes means for simultaneously broadcasting a line number allocated to the communication line when receiving a call and time information for limiting the start of the initial synchronization operation, and starting the operation of the initial synchronization based on the time information. Is provided in the calling station and the called station.

The power consumption saving method for a communication system according to the present invention is characterized in that when a call from a calling station to a called station via an uplink control line is accepted, the control station connects the calling station and the called station to a downlink control line. Simultaneously broadcast a line number to be assigned to the call line of the calling station, and based on the line number at the calling station and the called station,
A power saving method for a communication system in which a communication between the calling station and the called station is performed after the establishment of initial synchronization for preparation of reception of the communication line, wherein the method includes the steps of: When receiving a call to the called station, the control station broadcasts a line number to be assigned to the communication line and time information for limiting the start of the operation of the initial synchronization from the control station, and based on the time information, the calling station And controlling the start of the operation of the initial synchronization in the called station.

That is, in the communication system of the present invention, a control station receiving a call from a calling station simultaneously transmits a line number and time information to be allocated to the calling lines of the calling station and the called station via a downlink control line. Broadcasting, receiving the downlink control line and detecting the line number, assigns the line numbers of the transmitting unit and receiving unit at the calling station and the called station, and the transmitting unit talks to the telephone line based on the transmission request and time information. In addition to transmitting the data, the receiving unit starts an initial synchronization process based on the control signal of the power control unit obtained from the time information in order to prepare for receiving the communication line.

Thus, the initial synchronization processing is not performed during the period when there is no input signal, so that the power consumption can be reduced. This can be prevented.

[0015]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a communication system according to one embodiment of the present invention. Referring to FIG. 1, a communication system according to one embodiment of the present invention includes a control station 1, a calling station 2, and a called station 3.

FIG. 2 is a sequence chart showing a connection procedure of the communication system according to one embodiment of the present invention. The connection procedure of the communication system according to the embodiment of the present invention will be described with reference to FIGS.

The control station 1 sends an uplink control line # 1 from the calling station 2.
When the call information is received via the communication line, the line numbers (# 2, # 3) assigned to the call lines of the calling station 2 and the called station 3 on the downlink control line # 0 and the time information indicating the start of reception are broadcast simultaneously. I do.

The calling station 2 and the called station 3 are connected to a downlink control line # 0.
, The line numbers (# 2, # 3) of the transmitting unit and the receiving unit are assigned. In the calling station 2 and the called station 3 to which the line numbers are assigned, the transmitting unit transmits the call data to the call lines # 2 and # 3 based on the transmission request and the time information.

The receiving units of the calling station 2 and the called station 3 prepare for reception (standby) of the communication lines # 2 and # 3.
An initial synchronization process is started based on a control signal of a power control unit obtained from time information. In this case, the initial synchronization process stops after a period during which there is no received signal before the time information and after the initial synchronization is established. As a result, a call between the calling station 2 and the called station 3 is started.

FIG. 3 is a diagram showing a configuration of a frame signal of the downlink control line # 0 in FIG. In FIG. 3, the frame signal of the downlink control line # 0 is a continuous wave composed of a synchronization signal and a data section including a destination terminal number and time information, and includes a synchronization signal periodically.

FIG. 4 is a block diagram showing the configuration of the control line transmitting / receiving section of the control station 1 of FIG. In FIG. 4, a control line transmitting / receiving unit of the control station 1 includes a line control unit 11 and a transmitting unit 12.
, Spreading code generators 14, 18, a receiving unit 15, and a reference time generator 19. The transmitting unit 12 includes a modulator 13, and the receiving unit 15 includes a demodulator 16 and an initial synchronization circuit 17. Each has it.

The line controller 11 is a demodulator 16 of the receiver 15.
Demodulates outgoing call information from the uplink control line # 1 based on the spread code generated by the spread code generator 18 and outputs the demodulated information.
And transmits it to the downlink control line # 0.

Here, the transmitting section 12 and the receiving section 15 operate based on the clock signal from the reference time generator 19, and the modulator 13 of the transmitting section 12 uses the spreading code generated by the spreading code generator 14. And modulate the transmission signal to the downlink control line # 0.

FIG. 5 is a block diagram showing the configuration of the control line transmitting / receiving section of each of the calling station 2 and the called station 3 in FIG. FIG.
, The control line transmitting / receiving section of each of the calling station 2 and the called station 3 includes a line control section 21, a transmitting section 22, spreading code generators 24 and 28, and a receiving section 25. Reference numeral 22 denotes a modulator 23, and the reception unit 25 includes a demodulator 26 and an initial synchronization circuit 27.

When a call is instructed from a terminal (not shown), the line controller 21 transmits the call information to the modulator 23 of the transmitter 22.
And transmits it to uplink control line # 1. When the demodulator 26 of the receiving unit 25 demodulates the line number and time information from the downlink control line # 0 based on the spread code generated by the spread code generator 28 and outputs the demodulated signal. ,
The line number, the time information, and the setting flag are output to a communication line transmitting / receiving unit (not shown).

Here, the transmitting section 22 operates based on the frame synchronization signal detected by the receiving section 25, and the modulator 23 of the transmitting section 22 performs uplink control based on the spreading code generated by the spreading code generator 24. Modulate the signal to line # 1.

FIG. 6A is a block diagram showing the configuration of the communication line transmitting unit of the calling station 2 of FIG. 1, and FIG. 6B is a block diagram of FIG.
3 is a block diagram showing a configuration of a call line receiving unit of the calling station 2 of FIG. In FIG. 6 (a), the calling line transmitting unit of the calling station 2 includes a transmitting unit 32 having a modulator 33 and a line number setting (#
Spreading code generator 3 for generating a spreading code according to 2)
The transmitting unit 32 is connected to a terminal 31 and a communication line # 2 provided outside or inside the calling station 2.

In FIG. 6B, the communication line receiving section of the calling station 2 is provided with a receiving section 36 having a demodulator 37 and an initial synchronizing circuit 38 and an initial synchronizing circuit 38 based on a line setting flag and time information. A power control unit 39 for performing power control and a spreading code generator 40 for generating a spreading code according to the line number setting (# 3) are included. The receiving unit 36 is provided outside or inside the calling station 2. The terminal 35 and the communication line # 3 are connected to each other. Although not shown, the configurations of the communication line transmitting unit and the communication line receiving unit of the called station 3 are the same as those of the calling station 2 described above.

FIG. 7 is a timing chart showing the operation of the transmitting / receiving section of the calling station 2 and the called station 3 in FIG. The processing operation of the communication system according to the embodiment of the present invention will be described with reference to FIGS.

The control station 1 sends an uplink control line # 1 from the calling station 2.
When the calling information is received via the communication line, the downlink control line # 0 receives the line numbers (#
2, # 3) and time information [time indicating start of reception (for example,
X seconds after the current time)]. In this case, the time information is a signal for limiting the start of the initial synchronization operation in the initial synchronization circuit 38 of the receiving unit 37 of the calling station 2 and the called station 3.

The calling station 2 and the called station 3 are connected to the downlink control line # 0.
Is received to detect the line number, and the line numbers of the transmission unit 32 and the reception unit 36 are assigned based on the detection result. At this time,
The calling station 2 and the called station 3 receive the line setting information from the control station 1 after the synchronization of the downlink control line # 0 is completed. Further, the frame signal of the downlink control line # 0 is a continuous wave that periodically includes a synchronization signal, and once the initial acquisition is completed, the synchronization is maintained by tracking as in the related art.

When the calling station 2 and the called station 3 to which the line numbers are assigned receive the line setting flags from the line control unit 21,
The transmitting unit 32 transmits the call data to the call lines # 2 and # 3 based on the transmission request and the time information. The receiving unit 36
Is ready to receive (standby) the call lines # 2 and # 3
The initial synchronization process in the initial synchronization circuit 38 is started based on the control signal of the power control unit 39 obtained from the time information.

The initial synchronizing process in the initial synchronizing circuit 38 is stopped during a period in which there is no received signal before the time information on the communication line, and is stopped after the initial synchronization is established. That is, the initial synchronization process in the initial synchronization circuit 38 is performed from the time indicated by the time information until the initial synchronization is established.

Thereafter, a call is started between the calling station 2 and the called station 3 through the communication lines # 2 and # 3. However, if synchronization is lost after the call is started, resynchronization will be performed.

Here, the time information is stored in the control line transmitting / receiving section of the control station 1 shown in FIG. 4 and the calling station 2 and the called station 3 shown in FIG.
In each control line transmitting / receiving section, the value can be obtained based on the set value notified to the downlink control line # 0 and the timing signal extracted from the frame synchronization signal of the downlink control line # 0.

Also, since the synchronous preamble of the communication line is only one time, it is impossible to transmit before the other station enters the receiving state (the transmission needs to be delayed slightly). The reason why it takes a long time from the line setting flag to the transmission request is due to reasons such as polling time and timer waiting time.

In the above configuration, power saving of power consumption is on the order of several watts × several seconds. Also, first, the called side has a transmission request, and the calling side that has received the incoming response makes a next transmission request. Since the transmission request timings have the above-described order, they are not necessarily at the same time.

As described above, in response to the call information from the calling station 2, the control station 1 transmits the line number and the time information to the downlink control line # 0. By performing the initial synchronization processing based on the line setting flag and the time information, the initial synchronization processing is not performed during the period when there is no input signal, so that power consumption can be reduced and the period during which there is no input signal can be reduced. It is possible to prevent the occurrence of erroneous synchronization due to noise or multiplex signals.

[0039]

As described above, according to the present invention, when a call from a calling station to a called station via an up control line is accepted, the control station sends the calling station and the incoming call to the down control line. The broadcasting station broadcasts the line number assigned to the calling line, and the calling station and the called station use the line number to establish a communication between the calling station and the called station after establishing the initial synchronization in preparation for receiving the calling line. In a communication system for making a call, when a call from a calling station to a called station via an uplink control line is accepted, a line number assigned to the calling line and time information for limiting the start of initial synchronization operation are transmitted from the control station. Broadcasting simultaneously, by controlling the start of the initial synchronization operation at the calling station and the called station based on the time information,
This has the effect of reducing power consumption during standby time and preventing occurrence of erroneous synchronization.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a communication system according to an embodiment of the present invention.

FIG. 2 is a sequence chart showing a connection procedure of a communication system according to an embodiment of the present invention.

FIG. 3 is a diagram illustrating a configuration of a frame signal of a downlink control line # 0 in FIG. 1;

FIG. 4 is a block diagram illustrating a configuration of a control line transmitting / receiving unit of the control station in FIG. 1;

FIG. 5 is a block diagram showing a configuration of a control line transmitting / receiving section of each of a calling station and a called station in FIG. 1;

6A is a block diagram illustrating a configuration of a communication line transmitting unit of the calling station in FIG. 1, and FIG. 6B is a block diagram illustrating a configuration of a communication line receiving unit of the calling station in FIG. is there.

FIG. 7 is a timing chart showing the operation of the transmitting / receiving section of the calling station and the called station of FIG. 1;

FIG. 8 is a block diagram showing a configuration of a communication system according to a conventional example.

FIG. 9 is a sequence chart showing a connection procedure of a communication system according to a conventional example.

10A is a block diagram illustrating a configuration of a communication line transmitting unit of the calling station in FIG. 8, and FIG. 10B is a block diagram illustrating a configuration of a communication line receiving unit of the calling station in FIG.

FIG. 11 is a timing chart showing the operation of the transmitting / receiving section of the calling station and the called station in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Control station 2 Calling station 3 Calling station 11, 21 Line control part 12, 22, 32 Transmitting part 13, 23, 33 Modulator 14, 18, 24, 38, 34, 40 Spreading code generator 15, 25, 36 receiving unit 16, 26, 37 demodulator 17, 27, 38 initial synchronization circuit 19 reference time generator 31, 35 terminal 39 power control unit # 0 downlink control line # 1 uplink control line # 2, # 3 communication line

Claims (8)

[Claims] When a call from a calling station to a called station via an up control line is accepted, the control station assigns a line number assigned to the calling station and the calling line of the called station to a down control line. A communication that broadcasts simultaneously, and performs a call between the calling station and the called station after establishing initial synchronization for preparing to receive the communication line based on the line number at the calling station and the called station. A system for simultaneously broadcasting a line number to be assigned to the communication line and a time information for limiting the start of the initial synchronization operation when a call from the calling station to the called station is received via an uplink control line. A communication system, wherein the control station has means for controlling the start of the operation of the initial synchronization based on the time information in the calling station and the called station. 2. The time information is obtained from one of a set value notified to the downlink control channel and a timing signal extracted from a frame synchronization signal of the downlink control channel. 2. The communication system according to 1. 3. The operation of the initial synchronization is stopped in a period during which there is no received signal before the time indicated by the time information in the communication line and after the initial synchronization is established. The communication system according to claim 1 or 2. 4. The communication system according to claim 1, wherein a communication between the control station, the calling station, and the called station uses a spread spectrum system. 5. When a call from a calling station to a called station via an uplink control line is accepted, the control station assigns a line number assigned to the calling station and the calling line of the called station to a downlink control line. A communication that broadcasts simultaneously, and performs a call between the calling station and the called station after establishing initial synchronization for preparing to receive the communication line based on the line number at the calling station and the called station. A power consumption saving method for a system, comprising: a line number assigned to the communication line when a call from the calling station to a called station is received via an uplink control line, and a time for limiting the start of the initial synchronization operation. Information from the control station, and controlling the start of the initial synchronization in the calling station and the called station based on the time information. 6. The time information is obtained from one of a set value notified to the downlink control channel and a timing signal extracted from a frame synchronization signal of the downlink control channel. 5. The power consumption saving method according to 5. 7. The operation of the initial synchronization is characterized in that the operation is stopped in a period where there is no received signal before the time indicated by the time information in the communication line and after the initial synchronization is established. The power saving method according to claim 5. 8. The power consumption saving method according to claim 5, wherein a spread spectrum method is used for communication between the control station, the calling station, and the called station. Method.