JP2982724B2 - Transmission output power control method for multi-way multiplex communication system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

In the present invention, communication control is performed by a demand assignment system in which a radio communication channel is allocated between a slave station or a relay station and a master station only when a call is generated in the slave station or the relay station. The present invention relates to a multi-directional multiplex communication system, and more particularly to a transmission output power control method of an uplink burst signal from a lower station to an upper station.

[0002]

2. Description of the Related Art In general, a multi-directional multiplex communication system is disclosed in, for example, Japanese Patent Application Laid-Open No. 4-87732, in which one master station is surrounded by the master station and geographically isolated from each other. A time-division multiplexed wireless communication system that performs 1: N communication with a plurality of existing slave stations, and one or more relay stations may be installed depending on the system scale and the like. It itself also communicates with the master station.

In such a multi-way multiplex communication system, transmission of downlink communication information from a master station to each slave station is performed using a time division multiplexing (TDM) method. , And each slave station separates and selects the communication information targeted by itself. On the other hand, for transmission of communication information in the uplink direction from each slave station to the master station, each slave station transmits a transmission burst signal only within a predetermined transmission time range (called a radio time slot) assigned to itself. A predetermined communication information is transmitted to the master station using a time division multiple access (TDMA) system for transmitting (a burst signal whose transmission time is intermittent), and the master station transmits communication information from each slave station. Two-way communication is performed by taking them out separately.

FIG. 2 is a block diagram showing the outline of this type of multi-directional multiplex communication system. In FIG.
1 to B4 are a plurality of slave stations, and C is a relay station. An example of a system in which slave stations B3 and B4 among these slave stations B1 to B4 are wirelessly connected to a master station A via a relay station C is shown.

FIG. 3 is a diagram showing the structure of a radio frame, showing the structure of a downlink frame from the master station to each slave station and the structure of an uplink frame from each slave station to the master station.

[0006]

However, in the conventional multi-way multiplex communication system, each slave station or relay station sends the transmission output power of an uplink burst signal to an upper station in consideration of fading of a radio line. The data is transmitted at a constant level with a margin of several + dB.

[0007] In order to transmit the transmission output power in consideration of the fading time having a small occurrence time rate, interference of over-reach to a radio line of another route or other terrestrial communication using the same frequency is required. It also caused a disruption in satellite communications.

The present invention has been made in view of such a conventional problem, and reduces transmission output power of an uplink burst signal to a minimum level necessary for communication, thereby preventing interference with other wireless communication. The aim is to reduce

[0009]

According to the present invention, in order to achieve the above object, at the time of initial phase adjustment, the power transmitted from the slave station or the relay station to the upper station is first executed with the minimum power. When there is no response from the host station, the transmission output power level is increased stepwise to perform the adjustment.

Further, according to the present invention, the upper station periodically polls the lower station (slave station and relay station) for the purpose of monitoring the operation state of the equipment during operation. Communication is performed, and the transmission output power of the slave station or the relay station to be transmitted to the upper station is controlled by using the transmission output power control function at the time of the periodic polling.

Further, according to the present invention, when a call is generated in a slave station or a relay station, the transmission output power is controlled again with the reception level information from the upper station by periodic polling as an initial value when the line is connected, and the call is terminated. In some cases, the transmission output power is controlled.

According to the present invention, the transmission output power of the slave station or the relay station is controlled at the time of initial phase adjustment, the transmission output level is controlled at the time of periodic polling, and the transmission output power is controlled at the time of occurrence of a call and at the end of a call. Power control is performed.

[0013]

Next, the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing a transmission output power control method according to the present invention.

In FIG. 1, A is a master station and B is one slave station. Reference numeral 1 denotes an antenna of a slave station (lower station) B, and 2 denotes an antenna of a master station (upper station) A, which connects transmitters 5 and 6 and receivers 7 and 8 via circulators 3 and 4, respectively. . 9 on the slave station B side is the station number of the slave station, and 1
0 is a transmission output power control circuit, 11 is a reception level information detection circuit, 13 is a transmission multiplexing circuit, 15 is an initial phase adjustment control circuit, and 17 is a period polling information detection circuit.
Reference numeral 2 in the master station A indicates a reception level detection circuit, 14
Is a transmission multiplexing circuit, and 16 is a period polling control circuit.

Here, a method of controlling the transmission output power at the time of initial phase adjustment will be described.

The initial phase adjustment signal of the slave station B is generated by the initial phase adjustment control circuit 15, the station number information 9 is added thereto, the signal is guided from the transmission multiplexing circuit 13 to the transmitter 5, and transmitted to the master station A. You. At this time, the transmitter 5 can vary the transmission output power, but is operated with the transmission output power set to the minimum value at the time of initial startup. In the master station A, the reception level is detected by the reception level detection circuit 12 from the reception signal of the receiver 8, and this information is guided from the transmission multiplexing circuit 14 to the transmitter 6 and transmitted to the slave station B. In the slave station B, the reception level information detection circuit 1
At 1, the reception level information from the master station A is detected, and this information is fed back to the transmission output power control circuit 10. If the reception level information is lower than the specified value, the transmission output power control circuit 10 controls the transmitter 5 to increase the transmission output level next. In this way, when the reception level information reaches the specified value, the control of the transmission output level is stopped, and the operation shifts to the phase adjustment operation.

The transmitter 5 includes a transmission output power control circuit 1
Although the transmission power can be varied by a control signal from 0, this embodiment is shown in FIG. In the block diagram of FIG. 4A, the transmission baseband processing circuit 101
, Enters the modulator 103 and modulates the local signal from the local oscillator 102. The level of this modulated signal is controlled by a variable attenuator 104 using a transmission output power control signal and transmitted to a transmission power amplifier 105. In this way, the transmission output power is controlled by the control signal.

FIG. 4B shows another embodiment of the transmitter.
Is shown in the block diagram of FIG. In this embodiment, the transmission output power is varied by changing the bank of the transmission data signal in the ROM 106 by the transmission output power control signal. In this case, the address of the ROM 106 is divided into several banks in advance, and data in which the amplitude of the transmission signal is changed step by step by several dB is stored in each bank.

Next, a transmission output power control method at the time of periodic polling will be described. Normally, the master station A periodically polls the station numbers of the slave stations B and the relay station C from the master station A in order to monitor the operation state of each station with respect to all the slave stations and the relay station, and returns a monitoring control signal. Instruct. Master station A
The station number information of the slave station or the relay station to be monitored from the period polling control circuit 16 is guided to the transmitter 6 through the transmission multiplexing circuit 14 and transmitted to the lower station. When the slave station B confirms that the received signal of the receiver 7 matches the value of the station number 9 of the own station by the cycle polling information detection circuit 17, the slave station B transmits the monitoring control information to the master station at the time of the cycle polling. At this time, at this time, the control value of the transmission output power of the transmitter 5 uses the value at the time of the initial phase adjustment, or the value of the result if the periodic polling has been performed at least once before. The transmission output power is controlled as an initial value. The slave station B feeds back the reception level information sent from the master station to the transmitter 5 by the transmission output power control circuit 10 during the periodic polling period for the slave station. That is, when the reception level information is higher than the standard value, the transmission output power is reduced, and when the reception level information is lower than the standard value, the transmission output power is increased. At this time, the transmission output power control circuit 1
0 stabilizes the feedback circuit by integrating the reception level information within a range satisfying the required response speed.

[0021] In some cases, the relay station locally polls the local stations directly under the control of the own station, and stores the information monitored and controlled in this relay station. There is also a method in which monitoring and control information of all stations is collected quickly by collectively notifying the upper stations when the stations are periodically polled. It has the advantage that it can be done quickly.

Finally, a description will be given of a transmission output power control method at the time of line connection when a call occurs in a slave station or a relay station.

When a call is generated in a slave station or a relay station, a radio line setting protocol is transmitted / received between a master station A and a slave station B connected to the call when the line is connected. The output power control circuit 10 feeds back the reception level information sent from the master station to the transmitter 5 during the period polling period for the own station. Further, the same feedback is performed at the end of the call. As the control value of the transmission output power at this time, the value of the previous cycle polling is used, or the new control value of the value at the end of the previous call is used. In this way, the control of the transmission output power is performed at the time of line connection and at the time of call termination. With this control method, the control interval can be shortened as the number of subscribers accommodated in the slave station and the traffic volume increase.

So far, the transmission output power control method at the time of initial phase adjustment, at the time of period polling, and at the time of line connection when a call is generated in a slave station or a relay station has been described, respectively. For example, it is easy to think that more effective results can be obtained by implementing these methods in combination with each other, but not with each other.

[0025]

As described above, according to the present invention,
In the demand assignment multi-directional multiplex communication system, by controlling the uplink transmission output power of the slave station or the relay station during the initial phase adjustment, it is possible to minimize interference to other lines during the initial adjustment. it can.

According to the present invention, during operation, by controlling the transmission power in the uplink direction of the slave station or the relay station in synchronism with the periodic polling, interference of overreach to the radio line of another route is controlled. Alternatively, interference with other terrestrial communication and satellite communication using the same frequency can be avoided.

According to the present invention, it is possible to further increase the control interval by controlling the uplink transmission power of a slave station or a relay station when a call is generated and when a call is terminated. In addition, when the fading of the wireless channel occurs, it is possible to increase the response speed.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of a multi-way multiplex communication system.

FIG. 3 is a configuration diagram of a wireless frame.

FIGS. 4A and 4B are block diagrams each showing a configuration example of a transmitter of a slave station;

[Explanation of symbols]

 Reference Signs List 1 slave station antenna 2 master station antenna 3, 4 circulator 5, 6 transmitter 7, 8 receiver 9 station number 10 transmission output power control circuit 11 reception level information detection circuit 12 reception level detection circuit 13, 14 transmission multiplexing circuit 15 initial Phase adjustment control circuit 16 Period polling control circuit 17 Period polling information detection circuit 101 Transmission baseband processing circuit 102 Local oscillator 103 Modulator 104 Variable attenuator 105 Transmission power amplifier 106 ROM A Master station B1 to B4 Slave station C Relay station

Claims (5)

(57) [Claims] A communication control is performed by a demand assignment method in which a wireless communication channel is allocated between a slave station or a relay station and a master station only when a call is generated in the slave station or the relay station. When a transmission signal is sent to the upper station (relay station or master station), the upper station detects the reception level from the lower station (the slave station or relay station) and returns this reception level information to the lower station. In a multi-directional multiplex communication system having a function of controlling transmission output power to an upper station based on reception level information from an upper station, the power transmitted from the slave station or the relay station to the upper station is initially set at the time of initial phase adjustment. A transmission power control method for a multi-directional multiplex communication system, characterized in that, when there is no response from a higher station, the transmission power level is increased stepwise and adjustment is performed. . 2. A communication control is performed by a demand assignment method of allocating a wireless communication channel between the slave station or the relay station and the master station only when a call is generated in the slave station or the relay station. When a transmission signal is sent to the upper station (relay station or master station), the upper station detects the reception level from the lower station (the slave station or relay station) and returns this reception level information to the lower station. In a multi-directional multiplex communication system having a function of controlling transmission output power to an upper station based on reception level information from an upper station, during operation, the upper station communicates with the lower station (slave station and relay station). In order to monitor the operating state of the host station, the higher-level station periodically polls and executes the communication of the monitoring control signal.
A transmission output power control method for a multi-way multiplex communication system, comprising controlling transmission output power of a slave station or a relay station to be transmitted to an upper station. 3. The communication control is performed by a demand assignment method of allocating a wireless communication channel between the slave station or the relay station and the master station only when a call is generated in the slave station or the relay station. When a transmission signal is sent to the upper station (relay station or master station), the upper station detects the reception level from the lower station (the slave station or relay station) and returns this reception level information to the lower station. In a multi-way multiplex communication system having a function of controlling transmission output power to an upper station based on reception level information from an upper station, when a call occurs in a slave station or a relay station, the upper station performs periodic polling at line connection. The transmission output power of the multi-way multiplex communication system is characterized in that the transmission output power is controlled again with the reception level information from Power control method. 4. During operation, the upper station periodically polls the lower station (slave station and relay station) to execute monitoring control signal communication in order to monitor the operation state of the device. 2. The multidirectional multiplex communication system according to claim 1, wherein during the period polling, the transmission output power of the slave station or the relay station to be transmitted to an upper station is controlled using a transmission output power control function. Transmission power control method. 5. When a call is generated in a slave station or a relay station, the transmission output power is controlled again with the reception level information from the upper station by periodic polling as an initial value when the line is connected, and the transmission output power is also set when the call is terminated. 5. The transmission output power control method for a multi-directional multiplex communication system according to claim 1, wherein the power is controlled.