JP2508320B2 - Automatic phase adjustment method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an automatic phase adjustment method in a radio paging system, and in particular, a slave station selects one from a plurality of signal transmission paths with a master station and subordinates it. The present invention relates to an automatic phase adjustment method in a radio paging system configured to connect to a base station.

[Conventional technology]

In a part of the area in the radio paging system where the intensity of radio waves from a plurality of transmitters is the same, the received electric field strength is usually small due to the phase shift of the paging signals from the respective transmitters. For this reason, the reception rate of the mobile station called in this area deteriorates. As a means for preventing this, an automatic phase adjustment method for aligning the phases of the call signals from the transmitters is used. With this method, it is possible to prevent a decrease in reception rate even in an area where the strength of radio waves from a plurality of transmitters is about the same.

In the radio paging system having the function of aligning the phases of the calling signals as described above, the device having the function of creating and sending the calling signal is the master station, and the function of receiving the signal sent by the master station and adjusting the phase is provided. A device is called a slave station, and a device having a transmitter that sends out a signal whose phase is adjusted by the slave station is called a base station. The general connection relationship of each of these stations
Shown in the figure.

The automatic phase adjustment in the radio paging system having the configuration shown in FIG. 3 has been conventionally performed as follows.

First, determine the transmitter base station for phase adjustment. Here, consider the base station C1 and the base station C2. Next, the master station A outputs a control signal to turn on the transmission power of the base station C1. Following this control signal, a predetermined bit string is output. This bit string is radiated into the space from the base station C1 via the slave station B0, and is received by the receiver R1 arranged in the area where the radio waves from the base station C1 and the radio wave from the base station C2 have the same strength. , Come back to the slave station B0. Slave station
At B0, the phase of the bit string from the master station A and the phase of the bit string from the receiver R1 are compared to obtain the delay amount. After appropriately repeating the transmission of this bit string, a control signal is output to the base station C1 to turn off the transmission power.

Similarly, for the base station C2, the transmission power is turned on, a specific bit string is radiated, the slave station B1 receives the bit string through the receiver R1, and the delay amount is obtained.

The phase correction amount is calculated from the difference between the delay amounts obtained for the base stations C1 and C2, and the phase correction amount is set in the phase adjustment unit in the slave station B0 connected to the base station C1.

In this way, the phase of the signal radiated from the base station C1 can be matched with the phase of the signal radiated from the base station C2. By sequentially performing the same phase adjustment on other base stations, the phase adjustment of all base stations can be performed. This phase adjustment is periodically performed at regular intervals.

By the way, a signal transmission path connecting a master station and a slave station is generally duplicated. The reason is that if there is no signal transmission path that is switched when a failure occurs, the paging signal is not sent to the base station under the slave station, and the serviceability of the system is greatly impaired.

Consider the phase adjustment when the signal transmission path between the master station and the slave station is duplicated in this way. Signal signal transmission path from the base station _{A l 00, l 01, l} 10, through the l _11, the slave station BO,
It is sent to each slave station B1. In slave station BO, signal transmission path
Select either l ₀₀ or l ₀₁ to select the subordinate base stations C0, C1
Distribute to. The same applies to the slave station B1. As an example, assume that the signal transmission paths l ₀₁ and l ₁₀ are selected. The phase correction amount set in the phase adjustment unit of the slave station B0 or slave station B1 is optimized for the signal transmission paths l ₀₁ and l ₁₀ .

Here, consider a case where the signal transmission path l ₁₀ is changed to the signal transmission path l ₁₁ for some reason. The values set in each phase adjustment unit are optimized for the signal transmission paths l ₀₁ and l ₁₀ , so when using the signal transmission path l ₁₁ , the phase of the ringing signal radiated from the base station C1 And that of the base station C2 are not always transmitted together. This is because the delay amounts of the signal transmission paths l ₁₀ and l ₁₁ are generally different.

On the other hand, the phase adjustment is performed by sequentially designating the transmitters of the respective base stations, and the adjustments are made for all the transmitters. in this case,
After switching the signal transmission path from l ₁₀ to l ₁₁ , the base station C1
Until the phase adjustment between the base station and the base station C2 is completed and
The phases between the base stations C1 and C2 are not uniform. As a result, the received electric field strength may be reduced in a part of the area between the base stations C1 and C2 during this period, and the reception rate of the mobile device is reduced.

[Problems to be Solved by the Invention]

As described above, in the conventional automatic phase adjustment method,
Even if the signal transmission path from the master station changes, the amount of phase correction set in the phase adjustment unit remains the same, so the phase remains deviated due to the difference in delay amount in the signal transmission path between the master station and the slave station. , A ringing signal may be emitted. Since this state continues until the next phase adjustment is completed, there is a problem that the reception rate of the mobile device is deteriorated for a long time.

[Means for solving the problem]

The automatic phase adjustment method of the present invention is a master station and a plurality of base stations that radiate the master station output signal as a radio wave into space when it detects that the master station is designated by analyzing the master station output signal. Between the master station and a station, a radio receiver that outputs an output signal of the master station and is placed in an area where two strengths of the radio waves radiated by these base stations are about the same. And a phase adjustment signal included in the output signal of the master station, which is input via one selected from the signal transmission paths and has at least one base station under the signal transmission path, and From the phase difference with the phase adjustment signal input from the receiver, calculate the amount of phase correction for each of the subordinate base stations, set the phase adjustment unit corresponding to each of the subordinate base stations, and transmit the signal. The output signal of the master station input from the path is In an automatic phase adjustment method with a slave station that performs phase correction and output in the phase adjuster corresponding to each of the subordinate base stations, in the slave station, the phase correction amount for each of the signal transmission paths and A storage unit that stores each of the subordinate base stations, a signal transmission path monitoring unit that monitors which one of the signal transmission paths is selected, and the signal transmission path monitoring unit switches the signal transmission path. And a control unit that reads out the phase correction amount corresponding to the newly selected signal transmission path from the storage unit and sets it in the phase adjustment unit.

The storage unit included in the slave station provided in the automatic phase adjustment method of the present invention is configured by RAM, and the storage area of this RAM is divided into areas corresponding to the respective signal transmission paths, and each of these divided areas is divided. It may be divided corresponding to each of the subordinate base stations.

〔Example〕

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

FIG. 1 is a block diagram of one child station in one embodiment of the present invention.

The slave station shown in FIG. 1 is a slave station of the radio paging system generally shown in FIG. 3 and is connected to the master station by two signal transmission paths l ₀ and l ₁ and has three base stations under its control. I shall.

1 is a signal transmission path switching unit for connecting _one of the signal transmission paths l ₀ and l ₁ from the master station to the signal transmission path to the subordinate base station, and 2 is the signal transmission path from the master station path
A signal transmission path monitoring unit 3 for notifying which _one of l ₀ and l ₁ is connected to the signal transmission path to the subordinate base station is a phase corresponding to each of the signal transmission paths l ₀ and l ₁ from the master station. A storage unit for storing the adjustment amount, 4 is a phase adjustment unit that receives a phase correction amount and delays the phase according to the value, and 5 is a reception unit that receives a direct signal from the master station and a signal radiated into space. A delay measuring unit for measuring the amount of delay by comparing the phases with the signals returned from the devices (receivers RO, R1, R2, etc. in FIG. 3), and 6 is a control unit for controlling the above respective units. Storage unit 3
Is composed of RAM.

FIG. 2 is a diagram for explaining the memory area of the storage unit 3.

Corresponding to the two signal transmission paths with the master station, the memory area of the storage unit 3 is roughly divided into two. 10, 11, 12 in one of them is a memory area for storing the phase correction amount corresponding to the signal transmission path l ₀ . In the slave station shown in FIG. 1, the phase adjusting unit 4 corresponds to the fact that there are three subordinate base stations.
Since there are three memory areas, they are divided into three memory areas. 2
Reference numerals 0, 21, and 22 are memory areas for storing the phase correction amount corresponding to the signal transmission path l ₁ , and are divided into three memory areas for the same reason.

The signal transmission path monitoring unit 2 determines which of the signal transmission paths l ₀ and l ₁ is connected by monitoring the connection state of the changeover switch in the signal transmission path switching unit 1, and controls the determination result. Report to Department 6. Upon receiving this notification, the control unit 6 constantly monitors which signal transmission path is connected. When the signal transmission path l ₀ is connected, the memory areas 10, 11 and 12 are updated each time the phase adjustment is performed, and at the same time, the phase correction amount is set in each phase adjustment unit 4. When the signal transmission path l ₁ is connected, the memory areas 20, 21, 22 are updated, and at the same time, the phase correction amount is set in each phase adjusting section 4.

When the signal transmission route from the master station is switched from l ₀ to l ₁ , the control unit 6 immediately recognizes the change from the signal transmission route monitoring unit 2 and determines which signal transmission route it has moved to.
Since it has been switched to the signal transmission path l ₁ now, the signal transmission path l ₁
The phase correction amount is read from the memory areas 20, 21, and 22 corresponding to and is set in each phase adjustment unit 4. After that, until the signal transmission path is switched, the phase adjustment amount is set in the phase adjustment unit 4 each time the phase adjustment is performed, and at the same time, the memory areas 20, 21,
Update 22. On the contrary, when the signal transmission path is switched from l ₁ to l ₀ , the phase correction amount is read from the memory areas 10, 11 and 12 and set in each phase adjusting unit 4. After that, until the signal transmission path is switched, the phase correction amount is set in the phase adjustment unit 4, and at the same time, the memory areas 10, 11 and 12 are updated.

In this way, when the switching of the signal transmission path from the master station is detected, the phase correction amount is read from the memory area corresponding to the new signal transmission path and set in the phase adjustment unit 4, so that the new signal transmission path is set. This makes it possible to adjust the phase in a short time.

〔The invention's effect〕

As described above, the present invention has a storage unit that stores a phase correction amount corresponding to each signal transmission path from the master station,
Each time the phase adjustment is executed, the phase correction amount corresponding to the signal transmission path from the master station in the storage unit is updated, while the newly connected signal is detected when the signal transmission path from the master station is switched. By reading the phase correction amount corresponding to the transmission path from the storage unit and setting it in the phase adjustment unit, it becomes possible to quickly adjust the phase of the ringing signal without waiting for the next phase adjustment request from the master station. It is possible to provide the service without causing a decrease in the reception rate of the mobile device due to the phase shift of the ringing signal radiated from the base station.

[Brief description of drawings]

FIG. 1 is a block diagram of one child station in one embodiment of the present invention, FIG. 2 is a diagram for explaining a memory area of a storage unit 3 in FIG. 1, and FIG. 3 is a general radio calling system. It is a figure which shows a simple structure. 1 ...... signal transmission path switching unit, 2 ...... signal transmission path monitoring unit, 3 ...... storage unit, 4 ...... transmission adjustment unit, 5 ...... delay measurement unit, 6 ...... controller, l _0, l ₁ ... … Signal transmission path.

Claims (2)

(57) [Claims] 1. A master station, and a plurality of base stations that radiate the master station's output signal as a radio wave into space when it detects that the master station is designated by analyzing the master station's output signal. A plurality of signal transmission paths are provided between a radio receiver for outputting an output signal of the master station, which is arranged in a region where two strengths of the radio waves radiated by the base station are about the same, and the master station. And a phase adjustment signal included in the output signal of the master station, which is input via one selected from the signal transmission paths and which has at least one base station under the control, and is input from the receiver. The phase adjustment amount was calculated for each of the subordinate base stations from the phase difference with the phase adjustment signal, and the phase adjustment amount corresponding to each of the subordinate base stations was set and input from the signal transmission path. The output signal of the master station from the subordinate base station In an automatic phase adjustment method including a slave station that performs phase correction by the phase adjuster corresponding to each, and outputs, in the slave station, the phase correction amount for each of the signal transmission paths and the subordinate A storage unit that stores each of the base stations, and a signal transmission path monitoring unit that monitors which of the signal transmission paths is selected,
When the signal transmission path monitoring unit detects that the signal transmission path has been switched, the phase correction amount corresponding to the newly selected signal transmission path is read from the storage unit and set in the phase adjustment unit. An automatic phase adjustment method including a control unit. 2. The storage unit comprises a RAM, and the RAM
2. The automatic phase adjustment method according to claim 1, wherein said storage area is divided into areas corresponding to each of said signal transmission paths, and each of these divided areas is divided corresponding to each of said subordinate base stations.